Anti-influenza virus activities and mechanism of antrafenine analogs

Antrafenine is a drug initially designed for anti-inflammation uses. In this work we have synthesized a library of its structural analogs and tested the anti-influenza activities. These analogs belong to a group of 2-(quinolin-4-yl)amino benzamides or 2-(quinolin-4-yl)amino benzoate derivatives. Best performers were identified, namely 12, 34, 41, with IC50 against A/WSN/33 (H1N1) of 5.53, 3.21 and 6.73 μM respectively. These chemicals were also effective against A/PR/8/34 (H1N1), A/HK/1/68 (H3N2) and B/Florida/04/2006 viruses. Time-of-addition study and minigenome luciferase reporter assay both supported that the compounds act on the ribonucleoprotein (RNP) components. Using 34 and 41 as representative compounds, we determined by microscale thermophoresis that this group of compounds bind to both PA C-terminal domain and the nucleoprotein (NP) which is the most abundant subunit of the RNP. Taken together, we have identified a new class of anti-influenza compounds with dual molecular targets and good potential to be further developed. IMPORTANCE: The influenza viruses, especially influenza A and B subtypes, cause many deaths each year. The high mutation rate of the virus renders available therapeutics less effective with time. In this work we identify a new class of compounds, structurally similar to the anti-inflammation drug antrafenine, with good potency against influenza A strains. The IC50 of the best performers are within low micromolar range and thus have good potential for further development.

Bioassay guided isolation of caffeoylquinic acids from the leaves of Ilex pubescens Hook. et Arn. and investigation of their anti-influenza mechanism

ETHNOPHARMACOLOGICAL RELEVANCE

Ilex pubescens Hook. et Arn. (Maodongqing, MDQ) is a common herbal tea ingredient in Southern China for heat clearance and anti-inflammation. Our preliminary screening showed that 50% ethanol extract of its leaves has anti-influenza virus activity. In this report, we proceed to identify the active components and clarify the related anti-influenza mechanisms.

AIM

We aim to isolate and identify the anti-influenza virus phytochemicals from the extract of the MDQ leaves, and study their anti-influenza virus mechanism.

MATERIAL AND METHODS

Plaque reduction assay was used to test the anti-influenza virus activity of fractions and compounds. Neuraminidase inhibitory assay was used to confirm the target protein. Molecular docking and reverse genetics were used to confirm the acting site of caffeoylquinic acids (CQAs) on viral neuraminidase.

RESULTS

Eight CQAs, 3,5-di-O-caffeoylquinic acid methyl ester (Me 3,5-DCQA), 3,4-di-O-caffeoylquinic acid methyl ester (Me 3,4-DCQA), 3,4,5-tri-O-caffeoylquinic acid methyl ester (Me 3,4,5-TCQA), 3,4,5-tri-O-caffeoylquinic acid (3,4,5-TCQA), 4,5-di-O-caffeoylquinic acid (4,5-DCQA), 3,5-di-O-caffeoylquinic acid (3,5-DCQA), 3,4-di-O-caffeoylquinic acid (3,4-DCQA), and 3,5-di-O-caffeoyl-epi-quinic acid (3,5-epi-DCQA) were identified from the MDQ leaves, in which Me 3,5-DCQA, 3,4,5-TCQA and 3,5-epi-DCQA were isolated for the first time. All these eight compounds were found to inhibit neuraminidase (NA) of influenza A virus. The results of molecular docking and reverse genetics indicated that 3,4,5-TCQA interacted with Tyr100, Gln412 and Arg419 of influenza NA, and a novel NA binding groove was found.

CONCLUSION

Eight CQAs isolated from the leaves of MDQ were found to inhibit influenza A virus. 3,4,5-TCQA was found to interact with Tyr100, Gln412 and Arg419 of influenza NA. This study provided scientific evidence on the use of MDQ for treating influenza virus infection, and laid the foundation for the development of CQA derivatives as potential antiviral agents.

High-field magnetization and electronic spin resonance study in the twisted honeycomb latticeα-Mn2V2O7

We report the single-crystal growth of Mn₂V₂O₇and the results of magnetic susceptibility, high-field magnetization up to 55 T and high-frequency electric spin resonance (ESR) measurements for its low-temperatureαphase. Two antiferromagnetic (AFM) ordering at 17.5 K and 3 K and obvious magnetic anisotropy are observed inα-Mn₂V₂O₇upon cooling. In pulsed high magnetic fields, the compound reaches the saturation magnetic moment of ∼10.5μ_Bfor each molecular formula at around 45 T after two undergoing AFM phase transitions atH_c1≈ 16 T,H_c2≈ 34.5 T forH//[11-0] andH_sf1= 2.5 T,H_sf2= 7 T forH//[001]. In these two directions, two and seven resonance modes are detected by ESR spectroscopy, respectively. Theω₁andω₂modes ofH//[11-0] can be well described by two-sublattice AFM resonance mode with two zero-field gaps at 94.51 GHz and 169.28 GHz, indicating a hard-axis feature. The seven modes forH//[001] are partially separated by the critical fields ofH_sf1andH_sf2, displaying the two signs of spin-flop transition. The fittings ofω_c1andω_c2modes yield zero-field gaps at 69.50 GHz and 84.73 GHz forH//[001], confirming the axis-type anisotropy. The saturated moment and gyromagnetic ratio indicate the Mn²⁺ion inα-Mn₂V₂O₇is in a high spin state with orbital moment completely quenched. A quasi-one-dimensional magnetism with a zig-zag-chain spin configuration is suggested inα-Mn₂V₂O₇, due to the special neighbor interactions caused by a distorted network structure with honeycomb layer.

Anti-influenza properties of tiliroside isolated from Hibiscus mutabilis L

ETHNOPHARMACOLOGICAL RELEVANCE

Fu Rong Ye (FRY), the leaf of Hibiscus mutabilis L., is a Chinese medicinal herb used to treat coughs and respiratory diseases. FRY is the major herbal component of the patent medicine Fupo Ganmao Granules for treating common cold. However, its anti-influenza active components and mechanism were not identified.

AIM

Here, we aim to a) isolate the anti-influenza phytochemicals from FRY extract and b) explore its anti-flu mechanism.

MATERIAL AND METHODS

Bioassay guided isolation was performed to get anti-influenza virus components. Influenza virus infected cells and mouse model were employed for efficacy evaluation.

RESULTS

Using bioassay-guided isolation, the flavonoid tiliroside was obtained, which inhibited four IAV strains in MDCK cells with EC₅₀ ranging from 3.87 to 27.61 μM by suppressing the viral ribonucleoprotein activity. Tiliroside also significantly downregulated the expression of cytokines/chemokines in A549 cells, and protected 50% of PR8-infected BALB/c mice from death and at 800 mg/kg/day, improved lung edema conditions.

CONCLUSION

Tiliroside is effective for influenza virus infection treatment and promising for further drug development. This study is the first to demonstrate that tiliroside in FRY acts against influenza virus.

Interaction of Influenza A Nucleoprotein with Host hnRNP-C Is Implicated in Viral Replication

The host interactome of influenza viral proteins is ever-expanding. In this work, we report the identification of host heterogeneous nuclear ribonucleoprotein C (hnRNP-C) as an interacting partner of influenza A virus nucleoprotein (NP). We confirmed that this interaction exists across different influenza A subtypes and strains. Using biochemical methods, we determined that hnRNP-C interacts with NP via its C-terminal auxiliary domain. Further, we determined that the hnRNP-C is a negative regulator of influenza viral growth. Its interaction with NP is implicated in the promotion of host cell apoptosis during viral infection. It is the first time that the interaction between influenza nucleoprotein and host heterogeneous nuclear ribonucleoprotein C is characterized in detail. Overall, these findings not only characterize the interaction between NP and its host interacting partner hnRNP-C but also clarify the functional significance of this interaction. This work may lead to a new therapeutic target for the development of anti-influenza drugs.

Urolithin M5 from the Leaves of Canarium album (Lour.) DC. Inhibits Influenza Virus by Targeting Neuraminidase

Ganlanye (GLY), the leaf of Canarium album (Lour.) DC., is a traditional Chinese medicinal herb for warm disease treatment. We found that its aqueous extract could inhibit the influenza A virus. To find and characterize anti-influenza virus phytochemicals from GLY, we performed (1) bioassay-guided isolation, (2) a cell and animal assay, and (3) a mechanism study. Bioassay-guided isolation was used to identify the effective components. Influenza virus-infected MDCK cell and BALB/c mouse models were employed to evaluate the anti-influenza virus activities. A MUNANA assay was performed to find the NA inhibitory effect. As a result, urolithin M5 was obtained from the crude extract of GLY. It inhibited influenza virus activities in vitro and in vivo by suppressing the viral NA activity. In the MDCK cell model, urolithin M5 could inhibit an oseltamivir-resistant strain. In a PR8-infected mouse model, 200 mg/kg/d urolithin M5 protected 50% of mice from death and improved lung edema conditions. GLY was recorded as a major traditional herb for warm disease treatment. Our study identified GLY as a potent anti-influenza herb and showed urolithin M5 as the active component. We first report the in vivo activity of urolithin M5 and support the anti-influenza application of GLY.

Pore-Forming Cardiotoxin VVA2 (Volvatoxin A2) Variant I82E/L86K Is an Atypical Duplex-Specific Nuclease

VVA2 (volvatoxin A chain 2) is a cardiotoxic protein purified from Volvariella volvacea. Its biological activities include hemolysis, writhing reaction, neurotoxicity, and ventricular systolic arresting activity. The cytotoxicity of VVA2 was mainly considered due to its pore-forming activity. Here we report a novel biological activity of its variants VVA2 I82E/K86K as a duplex-specific nuclease. Recombinant VVA2 variant I82E/L86K (Re-VVA2 I82E/L86K), deprived of the oligomerization property, shows increased nuclease activity compared to VVA2. Re-VVA2 I82E/L86K converts supercoiled DNA (Replicative form I, RF I) into nicked form (RF II) and linear form (RF III) in the presence of Mg²⁺ or Mn²⁺. Besides plasmid DNA, it also exhibits nuclease activity on E. coli genomic DNA rather than ssDNA or RNA. Re-VVA2 I82E/L86K preferentially cleaves dG-dC-rich dsDNA regions and shows the best performance at pH 6–9 and 55 °C. Our structure–function study has revealed amino acid E111 may take an active part in nuclease activity through interacting with metal ions. Based on the sequences of its cleavage sites, a “double-hit” mechanism was thereby proposed. Given that Re-VVA2 I82E/L86K did not exhibit the conserved nuclease structure and sequence, it is considered an atypical duplex-specific nuclease.

Design, Synthesis, Molecular Docking Analysis and Biological Evaluations of 4-[(Quinolin-4-yl)amino]benzamide Derivatives as Novel Anti-Influenza Virus Agents

In this study, a series of 4-[(quinolin-4-yl)amino]benzamide derivatives as the novel anti-influenza agents were designed and synthesized. Cytotoxicity assay, cytopathic effect assay and plaque inhibition assay were performed to evaluate the anti-influenza virus A/WSN/33 (H1N1) activity of the target compounds. The target compound G07 demonstrated significant anti-influenza virus A/WSN/33 (H1N1) activity both in cytopathic effect assay (EC₅₀ = 11.38 ± 1.89 µM) and plaque inhibition assay (IC₅₀ = 0.23 ± 0.15 µM). G07 also exhibited significant anti-influenza virus activities against other three different influenza virus strains A/PR/8 (H1N1), A/HK/68 (H3N2) and influenza B virus. According to the result of ribonucleoprotein reconstitution assay, G07 could interact well with ribonucleoprotein with an inhibition rate of 80.65% at 100 µM. Furthermore, G07 exhibited significant activity target PA−PB1 subunit of RNA polymerase according to the PA−PB1 inhibitory activity prediction by the best pharmacophore Hypo1. In addition, G07 was well drug-likeness based on the results of Lipinski’s rule and ADMET prediction. All the results proved that 4-[(quinolin-4-yl)amino]benzamide derivatives could generate potential candidates in discovery of anti-influenza virus agents.

Novel mechanistic insight on the neuroprotective effect of berberine: The role of PPARδ for antioxidant action

Cerebral ischemic stroke ranks the second leading cause of death and the third leading cause of disability in lifetime all around the world, urgently necessitating effective therapeutic interventions. Reactive oxygen species (ROS) have been implicated in stroke pathogenesis and peroxisome proliferator-activated receptors (PPARs) are prominent targets for ROS management. Although recent research has shown antioxidant effect of berberine (BBR), little is known regarding its effect upon ROS-PPARs signaling in stroke. The aim of this study is to explore whether BBR could target on ROS-PPARs pathway to ameliorate middle cerebral artery occlusion (MCAO)-induced stroke. Herein, we report that BBR is able to scavenge ROS in oxidation-damaged C17.2 neural stem cells and stroked mice. PPARδ, rather than PPARα or PPARγ, is involved in the anti-ROS effect of BBR, as evidenced by the siRNA transfection and specific antagonist treatment data. Further, we have found BBR could upregulate NF-E2 related factor-1/2 (NRF1/2) and NAD(P)H:quinone oxidoreductase 1 (NQO1) following a PPARδ-dependent manner. Mechanistic study has revealed that BBR acts as a potent ligand (Kd = 290 ± 92 nM) to activate PPARδ and initiates the transcriptional regulation functions, thus promoting the expression of PPARδ, NRF1, NRF2 and NQO1. Collectively, our results indicate that BBR confers neuroprotective effects by activating PPARδ to scavenge ROS, providing a novel mechanistic insight for the antioxidant action of BBR.

Lyophyllin, a Mushroom Protein from the Peptidase M35 Superfamily Is an RNA N-Glycosidase

Ribosome-inactivating proteins (RIPs) hydrolyze the N-glycosidic bond and depurinate a specific adenine residue (A-4324 in rat 28S ribosomal RNA, rRNA) in the conserved α-sarcin/ricin loop (α-SRL) of rRNA. In this study, we have purified and characterized lyophyllin, an unconventional RIP from Lyophyllum shimeji, an edible mushroom. The protein resembles peptidase M35 domain of peptidyl-Lys metalloendopeptidases. Nevertheless, protein either from the mushroom or in recombinant form possessed N-glycosidase and protein synthesis inhibitory activities. A homology model of lyophyllin was constructed. It was found that the zinc binding pocket of this protein resembles the catalytic cleft of a classical RIP, with key amino acids that interact with the adenine substrate in the appropriate positions. Mutational studies showed that E122 may play a role in stabilizing the positively charged oxocarbenium ion and H121 for protonating N-3 of adenine. The tyrosine residues Y137 and Y104 may be used for stacking the target adenine ring. This work first shows a protein in the peptidase M35 superfamily based on conserved domain search possessing N-glycosidase activity.

Crystal structures of influenza nucleoprotein complexed with nucleic acid provide insights into the mechanism of RNA interaction

The nucleoprotein (NP) of influenza virus is the core component of the ribonucleoprotein (RNP) and performs multiple structural and functional roles. Structures of the influenza A, B and D NP molecules have been solved previously, but structural information on how NP interacts with RNA remains elusive. Here we present the crystal structure of an obligate monomer of H5N1 NP in complex with RNA nucleotides to 2.3 Å, and a C-terminal truncation of this mutant, also in complex with RNA nucleotides, to 3 Å. In both structures, three nucleotides were identified near two positive grooves of NP suggested to be important for RNA binding. Structural evidence supports that conformational changes of flexible loops and the C-terminal tail both play important roles in the binding of RNA. Based on the structure, we propose a mechanism by which NP captures RNA by flexible loops and transfers it onto the positive binding grooves. Binding of RNA by NP is a crucial step for template re-encapsidation during transcription and replication and cRNP formation. Our structures thus provide insights into the molecular virology of the influenza virus.

Interaction between influenza A virus nucleoprotein and PB2 cap-binding domain is mediated by RNA

Influenza A virus controls replication and transcription of its genome through the tight regulation of interaction between the ribonucleoprotein (RNP) complex subunits. The helical scaffold of RNP is maintained by nucleoprotein (NP). Previous studies have revealed that NP interacts with both PB2 N-terminal and C-terminal regions, with both regions sharing similar affinity to NP as revealed in co-immunoprecipitation assay. Our work here suggests that the interaction between NP and PB2 N-terminal region lies in the cap-binding domain (residue 320-483). By co-immunoprecipitation assay, the interaction was found to involve RNA. On the other hand, the cap-binding activity was not essential in the interaction. As shown by the NHS pull-down assay, a specific RNA sequence was not required. Among the cap-binding domain, residues K331 and R332 of PB2 play a role in RNP function so that polymerase activity was reduced when these residues were mutated, while K331 was found to be more crucial in the NP interaction. Collectively, our findings suggest a new binding mode between NP and PB2 which was mediated by RNA, and such interaction may provide a novel interacting site for influenza drug development.

Cytomegalovirus-associated acute respiratory failure in lupus patients: case reports in relation to cytomegalovirus biology

With the wide use of immunosuppressive agents, life-threatening cytomegalovirus-associated acute respiratory failure occurs frequently. However, this condition is yet to be fully recognized and the therapeutic approach to it can only be based on comprehensive protocols rather than the biological characteristics of cytomegalovirus. We describe three acute respiratory failure events that were related to the pathogenicity of cytomegalovirus, the primary cytopathic effect and secondary antiviral immunity-mediated damage. All cytomegalovirus infection occurred after immunosuppressive usage while the acute respiratory failure events took place in different clinical settings. The first acute respiratory failure event originated from the immunoinflammatory response after cytomegalovirus infection was circumscribed, while the second resulted from cytomegalovirus reactivation and the third was caused by the combined effect of acute cytomegalovirus infection and the subsequent immunoinflammatory response. According to the clinical setting, corresponding therapeutic approaches (sequential or combined strategy) were carried out. All the patients here presented were responsive to the above therapeutic strategies. Consequently, cytomegalovirus-associated acute respiratory failure in systemic lupus erythematosus patients should be carefully differentiated and a sequential or combined strategy should be carried out according to the clinical setting. Overall, we find that there are three patterns of cytomegalovirus-associated acute respiratory failure in systemic lupus erythematosus patients and propose a novel therapeutic strategy in relation to cytomegalovirus biology.

The Extended C-Terminal Region of Influenza C Virus Nucleoprotein Is Important for Nuclear Import and Ribonucleoprotein Activity

The influenza C virus (ICV) is a human-pathogenic agent, and the infections are frequently identified in children. Compared to influenza A and B viruses, the nucleoprotein of ICV (NPC) has an extended C-terminal region of which the functional significance is ill defined. We observed that the nuclear localization signals (NLSs) found on the nucleoproteins of influenza A and B virus subtypes are absent at corresponding positions on ICV. Instead, we found that a long bipartite nuclear localization signal resides at the extended C-terminal region, spanning from R513 to K549. Our experimental data determined that the KKMK motif within this region plays important roles in both nuclear import and polymerase activity. Similar to the influenza A viruses, NPC also binds to multiple human importin α isoforms. Taken together, our results enhance the understanding of the virus-host interaction of the influenza C virus.IMPORTANCE As a member of the Orthomyxoviridae family, the polymerase complex of the influenza C virus structurally resembles its influenza A and influenza B virus counterparts, but the nucleoprotein differs by possessing an extra C-terminal region. We have characterized this region in view of nuclear import and interaction with the importin α protein family. Our results demonstrate the functional significance of a previously uncharacterized region on Orthomyxoviridae nucleoprotein (NP). Based on this work, we propose that importin α binding to influenza C virus NP is regulated by a long bipartite nuclear localization signal. Since the sequence of influenza D virus NP shares high homology to that of the influenza C virus, this work will also shed light on how influenza D virus NP functions.

Uncertainties and implications of applying aggregated data for spatial modelling of atmospheric ammonia emissions

Ammonia emissions vary greatly at a local scale, and effects (eutrophication, acidification) occur primarily close to sources. Therefore it is important that spatially distributed emission estimates are located as accurately as possible. The main source of ammonia emissions is agriculture, and therefore agricultural survey statistics are the most important input data to an ammonia emission inventory alongside per activity estimates of emission potential. In the UK, agricultural statistics are collected at farm level, but are aggregated to parish level, NUTS-3 level or regular grid resolution for distribution to users. In this study, the Modifiable Areal Unit Problem (MAUP), associated with such amalgamation, is investigated in the context of assessing the spatial distribution of ammonia sources for emission inventories. England was used as a test area to study the effects of the MAUP. Agricultural survey data at farm level (point data) were obtained under license and amalgamated to different areal units or zones: regular 1-km, 5-km, 10-km grids and parish level, before they were imported into the emission model. The results of using the survey data at different levels of amalgamation were assessed to estimate the effects of the MAUP on the spatial inventory. The analysis showed that the size and shape of aggregation zones applied to the farm-level agricultural statistics strongly affect the location of the emissions estimated by the model. If the zones are too small, this may result in false emission "hot spots", i.e., artificially high emission values that are in reality not confined to the zone to which they are allocated. Conversely, if the zones are too large, detail may be lost and emissions smoothed out, which may give a false impression of the spatial patterns and magnitude of emissions in those zones. The results of the study indicate that the MAUP has a significant effect on the location and local magnitude of emissions in spatial inventories where amalgamated, zonal data are used.

Structure and Function of Influenza Virus Ribonucleoprotein

Influenza is a negative-sense single-stranded RNA virus with segmented genome. Each segment is encapsidated by a ribonucleoprotein (RNP) complex composed of RNA-dependent RNA polymerase (RdRP) and multiple copies of nucleoprotein (NP). The RNP complex plays a crucial role in viral life cycle, supporting and regulating transcription and replication of viral genome in infected cells. The structural characterization of RdRP and RNP in recent years has shed light on its functions and mechanism of action. In this review, we summarize current understanding on the structure of RNP complex, as well as the structure of each subunit. Crucial functions of RNP are also discussed.

Crystal Structure of Ribosome-Inactivating Protein Ricin A Chain in Complex with the C-Terminal Peptide of the Ribosomal Stalk Protein P2

Ricin is a type 2 ribosome-inactivating protein (RIP), containing a catalytic A chain and a lectin-like B chain. It inhibits protein synthesis by depurinating the N-glycosidic bond at α-sarcin/ricin loop (SRL) of the 28S rRNA, which thereby prevents the binding of elongation factors to the GTPase activation center of the ribosome. Here, we present the 1.6 Å crystal structure of Ricin A chain (RTA) complexed to the C-terminal peptide of the ribosomal stalk protein P2, which plays a crucial role in specific recognition of elongation factors and recruitment of eukaryote-specific RIPs to the ribosomes. Our structure reveals that the C-terminal GFGLFD motif of P2 peptide is inserted into a hydrophobic pocket of RTA, while the interaction assays demonstrate the structurally untraced SDDDM motif of P2 peptide contributes to the interaction with RTA. This interaction mode of RTA and P protein is in contrast to that with trichosanthin (TCS), Shiga-toxin (Stx) and the active form of maize RIP (MOD), implying the flexibility of the P2 peptide-RIP interaction, for the latter to gain access to ribosome.

Throughfall and bulk deposition of dissolved organic nitrogen to holm oak forests in the Iberian Peninsula: Flux estimation and identification of potential sources

Deposition of dissolved organic nitrogen (DON) in both bulk precipitation (BD) and canopy throughfall (TF) has been measured for the first time in the western Mediterranean. The study was carried out over a year from 2012 to 2013 at four evergreen holm oak forests located in the Iberian Peninsula: two sites in the Province of Barcelona (Northeastern Spain), one in the Province of Madrid (central Spain) and the fourth in the Province of Navarra (Northern Spain). In BD the annual volume weighted mean (VWM) concentration of DON ranged from 0.25 mg l(-1) in Madrid to 1.14 mg l(-1) in Navarra, whereas in TF it ranged from 0.93 mg l(-1) in Barcelona to 1.98 mg l(-1) in Madrid. The contribution of DON to total nitrogen deposition varied from 34% to 56% in BD in Barcelona and Navarra respectively, and from 38% in Barcelona to 72% in Madrid in TF. Agricultural activities and pollutants generated in metropolitan areas were identified as potential anthropogenic sources of DON at the study sites. Moreover, canopy uptake of DON in Navarra was found in spring and autumn, showing that organic nitrogen may be a supplementary nutrient for Mediterranean forests, assuming that a portion of the nitrogen taken up is assimilated during biologically active periods.

OX40 Ligand Levels and High-Sensitivity C-Reactive Protein Levels in Blood from Local Coronary Plaque and the Femoral Artery in Patients with Acute Coronary Syndrome or Stable Angina

OX40 ligand (OX40L) and high-sensitivity C-reactive protein (hs-CRP) play important roles in the pathogenesis of atherosclerosis. In this study, consecutive patients with acute coronary syndrome (ACS; n = 90) or stable angina (SA; n = 40) and healthy control subjects ( n = 50) were evaluated to assess plasma OX40L and serum hs-CRP levels in local coronary plaque and the femoral artery. OX40L and hs-CRP levels in the femoral artery were significantly higher in patients with ACS compared with controls. OX40L and hs-CRP levels in local coronary plaque (OX40Lc and hs-CRPc, respectively) were significantly higher in ACS than in SA patients. OX40L and hs-CRP levels were positively correlated with each other and were also correlated with fibrinogen levels. The number of complex lesions was correlated with OX40Lc and hs-CRPc levels. It is concluded that the OX40Lc level was highly sensitive for evaluating the inflammatory response in ACS and elevated levels of OX40Lc may be a valuable predictive marker for increased risk of atherosclerotic progression in ACS patients.

Experimental field estimation of organic nitrogen formation in tree canopies

The content of organic N has been shown in many studies to increase during the passage of rain water through forest canopies. The source of this organic N is unknown, but generally assumed to come from canopy processing of wet or dry-deposited inorganic N. There have been very few experimental studies in the field to address the canopy formation or loss of organic N. We report two studies: a Scots pine canopy exposed to ammonia gas, and a Sitka spruce canopy exposed to ammonium and nitrate as wet deposition. In both cases, organic N deposition in throughfall was increased, but only represented a small fraction (<10%) of the additional inorganic N supplied, suggesting a limited capacity for net organic N production, similar in both conifer canopies under Scottish summertime conditions, of less than 1.6 mmol N m(-2) mth(-1) (equivalent to 3 kg N ha(-1) y(-1)).

Development of a low-cost system for measuring conditional time-averaged gradients of SO2 and NH3

A conditional time-averaged gradient (COTAG) system has been developed to provide direct long-term (weekly to monthly) average flux gradient measurements for a range of trace gases, between land and atmosphere. Over daily periods, atmospheric conditions can range from high stability, where the vertical gradients of ambient concentration are enhanced due to very small diffusivity, to highly unstable conditions, in which concentration gradients are small due to the intense turbulent activity of the surface layer. The large vertical gradients generated by high stability would bias the estimate of the actual flux: to avoid this, the COTAG system samples conditionally, within a carefully refined range of stability. A comparison with a continuous flux gradient system suggested that the removal of stable conditions from the sampling period does not substantially modify the evaluation of the long-term fluxes.

A simple model for screening the local impacts of atmospheric ammonia

The dry deposition of ammonia from the atmosphere to the surface can lead to eutrophication of sensitive ecosystems and acidification of the soil. A large proportion of the ammonia emitted from agricultural sources can be deposited within a few kilometres and, therefore, impacts of ammonia dry deposition often occur near to the source. To assess these impacts, short-range atmospheric dispersion models are often applied to simulate the emission, dispersion and deposition of ammonia. However, these models can be time-consuming to run and often require detailed input data and, therefore, for multiple assessments it is useful to have a method of screening to discard scenarios where impacts are expected to be negligible. The SCAIL model (Simple Calculation of Ammonia Impact Limits) has been developed for this purpose. SCAIL estimates the atmospheric concentration and dry deposition at the nearest edge of a sensitive ecosystem (receptor) downwind of an ammonia source. These estimates are calculated based on simple meteorological data, the emission rate of the source, land cover type and distance to the receptor. Analysis of the model predictions showed that uncertainty in the model input data leads to an uncertainty in concentration and dry deposition estimates of 25-30% and 40-45% respectively. Detailed atmospheric dispersion models will also have similar uncertainties since they use similar types of input data. Comparison of the concentration predictions with previous measurements made around eight farms showed that the model significantly underestimated concentrations although the model performance was similar to existing screening techniques. The measurement dataset was used to calibrate the SCAIL model which subsequently performed better, using independent verification data, than existing models calibrated in a similar way. The benefits of the SCAIL model are already being seen in the UK, where it is used to screen farms for potential impacts on statutory nature conservation areas.

Modelling the spatial distribution of ammonia emissions in the UK

Ammonia emissions (NH3) are characterised by a high spatial variability at a local scale. When modelling the spatial distribution of NH3 emissions, it is important to provide robust emission estimates, since the model output is used to assess potential environmental impacts, e.g. exceedance of critical loads. The aim of this study was to provide a new, updated spatial NH3 emission inventory for the UK for the year 2000, based on an improved modelling approach and the use of updated input datasets. The AENEID model distributes NH3 emissions from a range of agricultural activities, such as grazing and housing of livestock, storage and spreading of manures, and fertilizer application, at a 1-km grid resolution over the most suitable landcover types. The results of the emission calculation for the year 2000 are analysed and the methodology is compared with a previous spatial emission inventory for 1996.

Evaluation of Free Flaps Transferred by Microvascular Anastomosis in Oral and Maxillofacial Surgery

The authors discuss indications for the use of microvascular free flaps transferred to the oral and maxillofacial region. A series of 139 cases, involving 145 free flaps, is reported over a three year period. The overall success rate for all types of flaps was 89.3%. Advantages and disadvantages of the use of various flaps are presented and suggestions are offered to avoid complications.

Challenges in quantifying biosphere-atmosphere exchange of nitrogen species

Recent research in nitrogen exchange with the atmosphere has separated research communities according to N form. The integrated perspective needed to quantify the net effect of N on greenhouse-gas balance is being addressed by the NitroEurope Integrated Project (NEU). Recent advances have depended on improved methodologies, while ongoing challenges include gas-aerosol interactions, organic nitrogen and N(2) fluxes. The NEU strategy applies a 3-tier Flux Network together with a Manipulation Network of global-change experiments, linked by common protocols to facilitate model application. Substantial progress has been made in modelling N fluxes, especially for N(2)O, NO and bi-directional NH(3) exchange. Landscape analysis represents an emerging challenge to address the spatial interactions between farms, fields, ecosystems, catchments and air dispersion/deposition. European up-scaling of N fluxes is highly uncertain and a key priority is for better data on agricultural practices. Finally, attention is needed to develop N flux verification procedures to assess compliance with international protocols.

Concentrations of ammonia and nitrogen dioxide at roadside verges, and their contribution to nitrogen deposition

Bimonthly integrated measurements of NO2 and NH3 have been made over one year at distances up to 10 m away from the edges of roads across Scotland, using a stratified sampling scheme in terms of road traffic density and background N deposition. The rate of decrease in gas concentrations away from the edge of the roads was rapid, with concentrations falling by 90% within the first 10 m for NH3 and the first 15 m for NO2. The longer transport distance for NO2 reflects the production of secondary NO2 from reaction of emitted NO and O3. Concentrations above the background, estimated at the edge of the traffic lane, were linearly proportional to traffic density for NH3 (microg NH3 m(-3) = 1 x 10(-4) x numbers of cars per day), reflecting emissions from three-way catalysts. For NO2, where emissions depend strongly on vehicle type and fuel, traffic density was calculated in terms of 'car equivalents'; NO2 concentrations at the edge of the traffic lane were proportional to the number of car equivalents (microg NO2 m(-3) = 1 x 10(-4) x numbers of car equivalents per day). Although absolute concentrations (microg m(-3)) of NH3 were five times smaller than for NO2, the greater deposition velocity for NH3 to vegetation means that approximately equivalent amounts of dry N deposition to road side vegetation from vehicle emissions comes from NH3 and NO2. Depending on traffic density, the additional N deposition attributable to vehicle exhaust gases is between 1 and 15 kg N ha(-1) y(-1) at the edge of the vehicle lane, falling to 0.2-10 kg N ha(-1) y(-1) at 10 m from the edge of the road.

Ammonia emission and deposition in Scotland and its potential environmental impacts

The main source of atmospheric ammonia (NH₃) in Scotland is livestock agriculture, which accounts for 85% of emissions. The local magnitude of emissions therefore depends on livestock density, type, and management, with major differences occurring in various parts of Scotland. Local differences in agricultural activities therefore result in a wide range of NH₃ emissions, ranging from less than 0.2 kg N ha⁻¹ year⁻¹ in remote areas of the Scottish Highlands to over 100 kg N ha⁻¹ year⁻¹ in areas with intensive poultry farming. Scotland can be divided loosely into upland and lowland areas, with NH₃ emission being less than and more than 5 kg N ha⁻¹ year⁻¹, respectively.Many semi-natural ecosystems in Scotland are vulnerable to nitrogen deposition, including bogs, moorlands, and the woodland ground flora. Because NH₃ emissions occur in the rural environment, the local deposition to sensitive ecosystems may be large, making it essential to assess the spatial distribution of NH₃ emissions and deposition. A spatial model is applied here to map NH₃ emissions and these estimates are applied in atmospheric dispersion and deposition models to estimate atmospheric concentrations of NH₃ and NH₄⁺, dry deposition of NH₃, and wet deposition of NHx. Although there is a high level of local variability, modelled NH₃ concentrations show good agreement with the National Ammonia Monitoring Network, while wet deposition is largest at high altitude sites in the south and west of Scotland. Comparison of the modelled NH_x deposition fields with estimated thresholds for environmental effects (“critical loads”) shows that thresholds are exceeded across most of lowland Scotland and the Southern Uplands. Only in the cleanest parts of the north and west is nitrogen deposition not a cause for concern. Given that the most intense effects occur within a few kilometres of sources, it is suggested that local spatial abatement policies would be a useful complement to traditional policies that mitigate environmental effects based on emission reduction technologies.

Identification of novel metabolites of pioglitazone in rat and dog

1. Four new metabolites of pioglitazone were identified by liquid chromatography-mass spectrometry (LC-MS/MS) as being formed by hydroxylation (M-VII and M-VIII), opening of the thiazolidinedione ring (M-X) and by desaturation of the terminal ethyl side chain or tether ethoxy moiety (M-IX), respectively. The structure of one of the hydroxylated metabolites (M-VII) was confirmed by chemical modification using the Jones reaction. 2. Oxidative cleavage of the thiazolidinedione ring is a novel pathway not previously reported for pioglitazone. 3. The hydroxylated M-VII was detected in incubations with rat, dog and human liver and kidney microsomes, and in plasma from rats and dogs dosed orally with [(3)H]pioglitazone. 4. The carboxylic acid derivative of M-VII (M-V) and its taurine conjugate were the major radioactive components in dog bile.

[A primary study on the relationship between condyle position and anterior distraction for cross bite caused by cleft lip and palate]

OBJECTIVE

To evaluate the changes of the position of the mandibular condyle in cleft lip and palate patients with secondary bony cross-bite deformity after early orthodontic treatment with extraoral bow and facial mask.

METHODS

The TMJ topograph 6 months before and after treatment was investigated in 8 patients. The width of the anterior,superior and posterior space of the TMJ was compared prior to and post treatment.

RESULTS

The results showed that there was no significant difference in the width of the three spaces of the TMJ before and after treatment.

CONCLUSION

The position of the mandibular condyle had no significant change after maxillary anterior distraction with extraoral bow and facial mask.

Potential for ammonia recapture by farm woodlands: design and application of a new experimental facility

There has been increasing pressure on farmers in Europe to reduce the emissions of ammonia from their land. Due to the current financial climate in which farmers have to operate, it is important to identify ammonia control measures that can be adopted with minimum cost. The planting of trees around farmland and buildings has been identified as a potentially effective and low-cost measure to enhance ammonia recapture at a farm level and reduce long-range atmospheric transport. This work assesses experimentally what fraction of ammonia farm woodlands could potentially remove from the atmosphere. We constructed an experimental facility in southern Scotland to simulate a woodland shelterbelt planted in proximity to a small poultry unit. By measuring horizontal and vertical ammonia concentration profiles within the woodland, and comparing this to the concentration of an inert tracer (SF6) we estimate the depletion of ammonia due to dry deposition to the woodland canopy. Together with measurements of mean ammonia concentrations and throughfall fluxes of nitrogen, this information is used to provide a first estimate of the fraction of emitted ammonia that is recaptured by the woodland canopy. Analysis of these data give a lower limit of recapture of emitted ammonia, at the experimental facility, of 3%. By careful design of shelterbelt woodlands this figure could be significantly higher.

A spatial analysis of atmospheric ammonia and ammonium in the U.K

As measures are implemented internationally to reduce SO2 and NOx emissions, attention is falling on the contribution of NH3 emissions to acidification, nitrogen eutrophication, and aerosol formation. In the U.K., a monitoring network has been established to measure the spatial distribution and long-term trends in atmospheric gaseous NH3 and aerosol NH4+. At the same time, an atmospheric chemistry and transport model, FRAME, has been developed with a focus on reduced nitrogen (NHx). The monitoring data are important to evaluate the model, while the model is essential for a more detailed spatial assessment. The national network is established with over 80 sampling locations. Measurements of NH3 and NH4+ (at up to 50 sites) have been made using a new low-cost denuder-filterpack system. Additionally, improved passive sampling methods for NH3 have been applied to explore local variability. The measurements confirm the high spatial variability of NH3 (annual means 0.06 to 11 microg NH3 m(-3)), consistent with its nature as a primary pollutant emitted from ground-level sources, while NH4+, being a slowly formed secondary product, shows much less spatial variability (0.14 to 2.4 mg NH4+ m(-3)). These features are reproduced in the FRAME model, which provides estimates at a 5-km level. Analysis of the underlying NH3 emission inventory shows that sheep emissions may have been underestimated and nonagricultural sources overestimated relative to emissions from cattle. The combination of model and measurements is applied to estimate spatial patterns of dry deposition to different vegetation types. The combined approach provides the basis to assess NHx responses across the U.K. to international emission controls.

Isolation and characterization of a folate receptor mRNA-binding trans-factor from human placenta. Evidence favoring identity with heterogeneous nuclear ribonucleoprotein E1

The interaction of an 18-base cis-element in the 5'-untranslated region of human folate receptor (FR)-alpha mRNA with a cytosolic trans-factor protein is critical for the translation of FR (Sun, X.-L., and Antony, A. C. (1996) J. Biol. Chem. 271, 25539-25547). This trans-factor was isolated to apparent homogeneity as a 43- and 38-kDa doublet from human placenta using poly(U)-Sepharose, followed by preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis and electro-elution as major purification steps. Amino acid microsequencing of two cyanogen bromide-generated peptide fragments of the 43-kDa trans-factor revealed complete identity with 43-kDa heterogeneous nuclear ribonucleoprotein E1 (hnRNP E1). Purified specific rabbit anti-hnRNP E1 peptide antibodies (generated against a synthetic oligopeptide that was not represented in microsequenced peptides of the trans-factor) also recognized the purified trans-factor on Western blots. Conversely, the 18-base FR RNA cis-element also bound hnRNP E1 protein on Northwestern blots. Moreover, a 19-base RNA cis-element in the 3'-untranslated region of 15-lipoxygenase mRNA that is known to bind hnRNP E1 also interacted with placental 43-kDa trans-factor. In addition, several murine tissues containing a hnRNP E1-related protein (also known as alphaCP-1) readily interacted with the 18-base FR RNA cis-element. Finally, anti-hnRNP E1 antibodies specifically inhibited translation of FR in vitro in a dose-dependent manner, and the antibody effect could be reversed in a dose-dependent manner by either purified trans-factor or hnRNP E1. Collectively, the data favor identity of the FR mRNA-binding trans-factor and hnRNP E1, confirm its critical role in the translation of FR, and highlight yet another role of multifunctional hnRNP E1 in eukaryotic mRNA regulation.

Development and types of passive samplers for monitoring atmospheric NO2 and NH3 concentrations

Numerous passive samplers based on the "Palmes-tube" have been developed for ambient air monitoring. In each case, the diffusion path length and/or cross-sectional area are modified to achieve the desired sampling rate. "Tube-type" samplers are low sensitivity samplers suitable for long-term monitoring, whereas the "badge-type" samplers have faster sampling rates suited to short-term monitoring. In the U.K., diffusion tubes are widely used for monitoring nitrogen dioxide (NO2) and ammonia (NH3). The open-ended diffusion tubes are prone to positive bias caused by incursion of wind eddies, leading to a shortening of the diffusion path. By using a porous membrane at the inlet, wind incursion is prevented, but an additional diffusion resistance is imposed and it is necessary to calibrate the tubes against a reference method to obtain an effective sampling rate. For NO2 sampling, positive bias also arises from the reaction of NO with O3 within the sampler. The interference from the chemical reaction is severe close to NO sources, with errors up to 30% for curbside locations when using the "tube-type" sampler. In rural areas, where NO concentrations are small relative to NO2, these errors are small. In some implementations, there is also a negative bias over long sampling periods caused by the degradation of trapped NO2. The low sampling rates of diffusion tubes make them too uncertain for use at background NH3 concentrations (<1 microg NH3 m(-3)) where they significantly overestimate concentrations. Badge-type samplers such as the "Willems badge" samplers permit accurate sampling at low ambient NH3 concentrations, but suffer from saturation at high concentrations and sensitivity to wind speed. A passive sampler optimised for monthly measurements of NH3 is reported here, together with its application in the U.K. National Ammonia Monitoring Network.

Comparison of low cost measurement techniques for long-term monitoring of atmospheric ammonia

An inter-comparison of techniques for long-term sampling of atmospheric ammonia (NH3) was conducted with a view to establishing a national network with > 50 sites. Key requirements were for: a low cost system, simplicity and durability to enable a postal exchange with local site operators, a precision of < +/- 20% for monthly sampling at expected NH3 concentrations of 1-2 micrograms m-3, a detection limit sufficient to resolve the small NH3 concentrations (< 0.2 microgram m-3) expected in remote parts of the UK, and a quantitative means to establish quality control. Five sampling methods were compared: A, a commercially available membrane diffusion tube (exposed in triplicate), with membranes removed immediately after sampling; B, the above method, with the membranes left in place until analysis; C, open-ended diffusion tubes (exposed with 4 replicates); D, a new active sampling diffusion denuder system; and E, an active sampling bubbler system. Method D consisted of two 0.1 m acid coated glass denuders in series with sampling at approximately 0.3 l min-1. These methods were deployed at 6 locations in the UK and the Netherlands and compared against reference estimates. Method D was the most precise and sensitive of the techniques compared, with a detection limit of < 0.1 microgram m-3. The bubbler provided a less precise estimate of NH3 concentration, and also suffered several practical drawbacks. The diffusion tubes were found to correlate with the reference at high concentrations (> 3 micrograms m-3), but were less precise and overestimated NH3 at smaller concentrations. Of the passive methods, A was the most precise and C the least precise. On the basis of the results, method D has been implemented in the national network, together with application of method A to explore spatial variability in regions with expected high NH3 concentrations.

Inhibition of phosphodiesterase type III before aortic cross-clamping preserves intramyocardial cyclic adenosine monophosphate during cardiopulmonary bypass

Inotropes are often used to treat myocardial dysfunction shortly after cardiopulmonary bypass (CPB). beta-Adrenergic agonists improve contractility, in part by increasing cyclic adenosine monophosphate (cAMP) production, whereas phosphodiesterase type III inhibitors prevent its breakdown. CPB is associated with abnormalities at the beta-receptor level and diminished adenyl cyclase activity, both of which tend to decrease cAMP. These effects may be increased in the presence of preexisting myocardial dysfunction. We tested the hypothesis that inhibition of phosphodiesterase type III before global myocardial ischemia and pharmacologic arrest results in the preservation of intramyocardial cAMP concentration during CPB. Twenty adult patients undergoing coronary artery bypass grafting with CPB were studied. After CPB was instituted, a myocardial biopsy was obtained from the apex of the left ventricle. Patients were randomized to receive either placebo or milrinone (50 micro/kg) through the bypass pump 10 min before aortic cross-clamping. Another myocardial biopsy was performed adjacent to the left ventricular apex just before weaning from CPB. Myocardial cAMP concentration was determined by radioimmunoassay. Myocyte protein content was determined by the Bradford method by using a commercial kit. There were no significant demographic differences between the groups; however, patients in the Milrinone group had a lower left ventricular ejection fraction than placebo (41% +/- 13% vs 53% +/- 7%; P < 0.05). Patients who received milrinone had larger cAMP concentrations at the end of CPB compared with placebo (21 +/- 12.5 pmol/mg protein versus 12.8 +/- 2.2 pmol/mg protein; P < 0.05). The administration of milrinone before aortic cross-clamping is associated with increased intramyocardial cAMP concentration at the end of CPB.

IMPLICATIONS

The administration of a single dose of milrinone before aortic cross-clamping resulted in significantly larger intramyocardial cyclic adenosine monophosphate concentration in myocardial biopsy specimens compared with controls.

[Assessment of velopharyngeal function in normal speech by CT]

OBJECTIVE

To find an objective method to assess velopharyngeal function by CT.

METHODS

Three dimensional conformation of the velopharyngeal orifice of 30 subjects with normal speech at rest and /i:/ position were observed and analyzed. The linear distance and area of velopharyngeal orifice were measured and analyzed statistically.

RESULTS

The average minimal area of velopharyngeal orifice at/i:/ position was 11.92+/-11.73 mm(2). The physical RVPI was 4.03+/-4.03%. Coronary closure was the most common type of velopharyngeal contraction which accounted for 50%, semi-ring type being 30%, and ring type being 20%. No sagittal closure were seen in this study. There were 70% subjects whose position of velopharyngeal closure was at the level of the first cervical vertebra, 26.7% above the level and 3.3% below it. The arrange of velopharyngeal closure was 9-12 mm in 83.4% subjects, and 3-6mm in 16.6%.

CONCLUSION

As a method of assessing velopharyngeal function, CT can not only observe the conformation of velopharyngeal orifice in three dimensions, but also quantitatively analyze the velopharyngeal function.

[Embolization of AVM of jaws]

OBJECTIVE

To report our experience to embolize the AVM of jaws by direct percutaneous puncture. in conjunction with endovascular therapy.

METHODS

3 cases of AVM of mandible and 3 cases of AVM of maxilla comprised this study group. The patients were embolized with fibered coils, PVA and NBCA. The coils were placed directly into the center of the intraosseous lesion. The procedure was under the guidance of DSA machine (PHILIPS V3000).

RESULTS

The acute arterial bleeding in 4 patients was controllable. The other two cases with oozing bleeding and a warm soft mass on the left face with a palpable pulse respectively, their symptoms and signs got improved a lot. The pericoronal oozing of blood in all patients disappeared during a 3 to 24 months follow-up and new bone formation was found in the follow-up radiography.

CONCLUSION

The embolization of the AVM of jaws by direct percutaneous puncture in conjunction with endovascular therapy is effective and safe, however the longer follow-up is expected.

[Correlation between the changes of soft and hard tissue after advanced Lefort I osteotomy in patients with cleft lip and palate]

OBJECTIVE

The purpose is to evaluate the correlation between the changes of soft and hard tissue after advanced Lefort I osteotomy in patients with complete unilateral cleft lip and palate.

METHODS

Lateral cephalometric films were taken from before and after operation. The same landmarks in two films were compared horizontally and vertically. The correlation ratio between changes of soft and hard tissue were analysed statistically.

RESULTS

After operation, the length of upper lip of the patients with CLP increased. The ratio between the movement of upper incisor and upper lip was 0.77 horizontally and 0.67 vertically, respectively.

CONCLUSION

The slope between hard and soft tissue was treated as ratio. It is more significant than the horizontal difference between soft and hard tissue, since correlative factor was contained in the slope.

[Cephalometric analysis on patients with TMJ ankylosis in different ages]

OBJECTIVE

To determine the cephalometric characteristics of the patients with TMJ ankylosis in deferent ages and to find the relationship between the period with TMJ and the cephalometric characteristics.

METHODS

By cephalometric analysis of 46 male patients with TMJ ankylosis and several normal people in deferent ages, we detected the relationship among the ages of the patients, the period with TMJ ankylosis and the cephalometric characteristics by means of SPSS for Win 95/98.

RESULTS

The cephalometric characteristics of the patients showed their maxilla and mandible retruded in posterior and superior direction, the hyoid bone displaced posteriorly and inferiorly. The middle and inferior pharygeal space decreased, the TSA/OPA increased significantly. There was an obvious positive correlation between the period with TMJ and hyoid bone position(r=0.46, p=0.009; Y=1.58+0.56X), and remarkable positive correlation between the period with TMJ and TSA/OPA(r=0.5, p=0.00 Y=72.76+0.64X).

CONCLUSION

In patients with TMJ ankylosis, the mandible and maxilla retruded posteriorly and superiorly,the hyoid bone displaced posteriorly and inferiorly, the middle and inferior pharygeal space decreased, the TSA/OPA increased remarkably. The longer the period with TMJ ankylosis, the more serious the deformities of the patients in craniomaxillofacial region.

Nodulisporic acid opens insect glutamate-gated chloride channels: identification of a new high affinity modulator

Nodulisporic acid (NA) is an indole diterpene fungal product with insecticidal activity. NA activates a glutamate-gated chloride channel (GluCl) in grasshopper neurons and potentiates channel opening by glutamate. The endectocide ivermectin (IVM) induces a similar, but larger current than NA. Using Drosophila melanogaster head membranes, a high affinity binding site for NA was identified. Equilibrium binding studies show that an amide analogue, N-(2-hydroxyethyl-2,2-(3)H)nodulisporamide ([(3)H]NAmide), binds to a single population of sites in head membranes with a K(D) of 12 pM and a B(max) of 1.4 pmol/mg of protein. A similar K(D) is determined from the kinetics of ligand binding and dissociation. Four lines of evidence indicate that the binding site is a GluCl. First, NA potentiates opening of a glutamate-gated chloride current in grasshopper neurons. Second, glutamate inhibits the binding of [(3)H]NAmide by increasing the rate of dissociation 3-fold. Third, IVM potently inhibits the binding of [(3)H]NAmide and IVM binds to GluCls. Finally, the binding of [(3)H]IVM is inhibited by NA. The B(max) of [(3)H]IVM is twice that of [(3)H]NAmide, and about half of the [(3)H]IVM binding sites are inhibited by NA with high affinity (K(I) = 25 pM). In contrast, [(3)H]IVM binding to Caenorhabditis elegans membranes is not inhibited by NA at 100 nM, and there are no high affinity binding sites for NA on these membranes. Thus, half of the Drosophila IVM receptors and all of the NA receptors are associated with GluCl. NA distinguishes between nematode and insect GluCls and identifies subpopulations of IVM binding sites.

Evaluation of the treatment for micromandibular deformity by distraction osteogenesis with submerged intraoral device

OBJECTIVE

To evaluate the results of distraction osteogenesis for correcting the micromandible with an intraoral device.

MATERIALS AND METHODS

Eight cases of micromandible resulting from temporomandibular joint (TMJ) ankylosis and first and second branchial arch syndrome received treatment by distraction osteogenesis. Subjects included 5 females and 3 males, ranging in age from 10 to 43 years (avg 20.25). Five micromandibles were associated with obvious mandibular asymmetry. An osteotomy was performed on bilateral mandibular bodies by intraoral approach. Elongation was started on the 5th or 6th day postoperation at a rate of 0.8 to 1 mm per day. The distractors were removed after a consolidation period from 71 to 139 days.

RESULTS

The distractions were fulfilled with a range of 8.5 to 24.4 mm. Pain appeared in osteotomy region when the 1 mm distraction was carried out once a day and disappeared when it was divided into twice a day. Mandibular lengthening was successful. Micromandible and facial asymmetries were corrected satisfactorily. The follow-up period ranged from a minimum of 1 month to a maximum of 10 months. There was no recurrence. One case of soft tissue infection and one case of lower lip numbness were reported. There were no cases of infection or other disturbance of wound healing or pseudarthrosis.

CONCLUSIONS

Because of its advantage in little injury, avoiding bone grafting, and few complications, intraoral distraction osteogenesis is a valuable approach to correct mandibular agenesis. However, in the management of mandibular deformities, distraction osteogenesis achieves better results when combined with other orthognathic operations. How to control the direction of distraction is a problem that needs further study.

[Early face mask treatment for maxillary hyperplasia in patients with cleft lip and Palate]

OBJECTIVE: Early interfering orthodontics were used to treat maxillary hyperplasia by face mask and extra-oral bow technique in teenages.The position changes of maxilla after orthodontic treatment were evaluated.METHODS:The cephlometric variables before and after treatment were measured.Variables after treatment were compared with normal values in children with same ages,and changes of the maxillary position was determind.RESULTS:The position of the maxilla after orthopedics was significantly advanced (P<0.001),but there was still difference from normal values.CONCLUSION:In the peroid of mixed dentition of patients with cleft lip and palate,early orthodontics on maxillary hyperplasia could stimulate maxillary development and growth,remove or improve crossbite,extra-oral bow and face mask were efficient tools for this kind of patients.

[A preliminary cephalometric study on characters of facial soft tissue in mandibular asymmetry cases]

OBJECTIVE: To study the alterations of facial soft tissue in mandibular asymmetry cases.METHODS:The asymmetric rates of the bone were compared with that of soft tissue by cephalometric analysis in 20 mandibular asymmetry cases by study on the thickness of the soft tissue in special position.RESULTS:It showed that the soft tissue is more symmetric than the bones.CONCLUSION:It can be concluded that the facial soft tissue is not as asymmetric as the bone.This suggests that the reconstrction of the bony deformities and the soft tissue deformities should not be performed at same time.

Disposition of L-732,531, a potent immunosuppressant, in rats and baboons

L-732,531 is a semi-synthetic analog of the macrolide tacrolimus (Prograf(R)). Like tacrolimus, L-732,531 is a potent immunosuppressant. In this study, its absorption, distribution, metabolism, and excretion were studied in rats and baboons. In rats, its blood and plasma levels were similar, whereas in baboons, its blood levels were, on average, twice as high as those in plasma. This was consistent with the in vitro blood-to-plasma ratio of L-732, 531, which in these two species, as well as in humans, was much lower than that of tacrolimus and showed a minimal concentration dependence. After iv administration to rats, the blood and plasma clearance of L-732,531 decreased from approximately 60 ml/min/kg at 0.2 mg/kg to 30 ml/min/kg when dosed at 1 and 3 mg/kg. After oral administration, plasma area under the concentration vs. time curve (AUC) and maximal plasma concentration (Cmax) increased more than proportionally to the dose. At 1, 5, and 15 mg/kg, plasma AUC was 29, 466, and 2832 ng.hr/ml, respectively, and Cmax was 10, 129, and 304 ng/ml, respectively. Bioavailability, although compromised by nonlinear kinetics, was estimated to be between 8% and 18%. In baboons, the clearance of L-732,531 was lower than that in rats, especially when calculated from blood concentrations (12 ml/min/kg at 0.2 mg/kg and 8 ml/min/kg at 1 mg/kg). After oral dosing, baboon plasma AUC and Cmax were much lower than those in rats, but as in rats, they increased more than proportionally with increasing doses. The bioavailability of L-732,531 in baboons was estimated at 3%, 9%, and 24% when animals were dosed at 5, 15, and 26 mg/kg po, respectively. After oral administration of [3H]L-732,531 at 5 mg/kg, approximately 32% of the radioactivity was recovered in bile and urine of rats, compared with 9% in baboons. High-performance liquid chromatography profiles of rat and baboon plasma, bile, urine, and feces indicated that L-732,531 was metabolized extensively to a complex mixture of products. Some intact parent drug was observed in feces of orally dosed animals, indicating incomplete absorption. In vitro, L-732,531 was metabolized more extensively by baboon liver microsomes than rat or human microsomes. Its metabolism in human liver microsomes was shown to be catalyzed primarily by cytochrome P450 3A isozymes.

[The evaluation of computer-aided simulating system in orthognathic surgery]

OBJECTIVE: The purpose of this study is to evaluate the reliabillty of computer-aided simulating system for orthognathic system. METHODS: 24 cases with dentofacial deformities were undergone treatment of orthognathic surgery.The presurgical cephalograms and profiles were input to the computer and were digitized.The simulated profiles and cephalometric analysis were obtained by the simulating system,and computer with the actual posttreatment cephalograms. RESULTS: The prodicted and actual posttreatment soft tissue line drawings were quite similar in all areas except for the lower lip region. CONCLUSION: In all cases,the actual images were judged more esthetic than the predicted images. It allayed the fears that the computer generated predictions were unrealistically and ideal.