Impact of a pyridazine derivative on tripartite synapse ultrastructure in hippocampus: a three-dimensional analysis.

Introduction: We previously discovered a pyridazine derivative compound series that can improve cognitive functions in mouse models of Alzheimer's disease. One of the advanced compounds from this series, LDN/OSU-0215111-M3, was selected as the preclinical development candidate. This compound activates local protein translation at the perisynaptic astrocytic process (PAP) and enhances synaptic plasticity sequentially. While biochemical evidence supports the hypothesis that the compound enhances the structural plasticity of the tripartite synapse, its direct structural impact has not been investigated. Methods: Volume electron microscopy was used to study the hippocampal tripartite synapse three-dimensional structure in 3-month-old wild-type FVB/NJ mice after LDN/OSU-0215111-M3 treatment. Results: LDN/OSU-0215111-M3 increased the size of tertiary apical dendrites, the volume of mushroom spines, the proportion of mushroom spines containing spine apparatus, and alterations in the spine distribution across the surface area of tertiary dendrites. Compound also increased the number of the PAP interacting with the mushroom spines as well as the size of the PAP in contact with the spines. Furthermore, proteomic analysis of the isolated synaptic terminals indicated an increase in dendritic and synaptic proteins as well as suggested a possible involvement of the phospholipase D signaling pathway. To further validate that LDN/OSU-0215111-M3 altered synaptic function, electrophysiological studies showed increased long-term potentiation following compound treatment. Discussion: This study provides direct evidence that pyridazine derivatives enhance the structural and functional plasticity of the tripartite synapse.

Correction: Pentacyclic spermidine alkaloids with radioprotective and anti-inflammatory activities from Orychophragmus violaceus.

Correction for 'Pentacyclic spermidine alkaloids with radioprotective and anti-inflammatory activities from Orychophragmus violaceus' by Zan-Xin Xu et al., Org. Biomol. Chem., 2021, 19, 9844-9848, DOI: 10.1039/D1OB01973B.

Pentacyclic spermidine alkaloids with radioprotective and anti-inflammatory activities from Orychophragmus violaceus.

Two pairs of novel pentacyclic spermidine alkaloid enantiomers, (±)-orychoviolines A and B ((±)-1 and (±)-2), were isolated from the seeds of Orychophragmus violaceus and represented the first example of a 2-piperidinone-fused hydrodibenzofuran skeleton, constructed from a 6/5/6/6 tetracyclic system and an 18 atomic ring. The most unexpected novelty was the formation of one more piperidinone ring by a connection between C-6 and N-7. Their structures and absolute configurations were determined by spectroscopic analyses, X-ray crystallography, and ECD analysis. Compared to Ex-RAD (sodium salt of 4-carboxystyryl-4-chlorobenzylsulfone), (-)-1 exhibited a significant radioprotective effect on cell survival and DNA damage. (-)-1 also exhibited remarkable anti-inflammatory activity by inhibiting the production of NO in RAW 264.7 cells activated by lipopolysaccharide with an IC50 value of 20.3 ± 1.58 µM, which was equivalent to that of dexamethasone.

Restoring tripartite glutamatergic synapses: A potential therapy for mood and cognitive deficits in Gulf War illness.

Gulf War illness is associated with a combination of exposure to war-related chemical agents and traumatic stress. Currently, there are no effective treatments, and the pathophysiology remains elusive. Neurological problems are among the most commonly reported symptoms. In this study, we investigated the glutamatergic system in the hippocampi of mice exposed to war-related chemical agents and stress. Mice developed Gulf War illness-like symptoms, including mood deficits, cognitive impairments, and fatigue. They exhibited the following pathological changes in hippocampi: elevated extracellular glutamate levels, impaired glutamatergic synapses, astrocyte atrophy, loss of interneurons, and decreased neurogenesis. LDN/OSU-215111 is a small-molecule that can strengthen the structure and function of both the astrocytic processes and the glutamatergic synapses that together form the tripartite synapses. We found that LDN/OSU-215111 effectively prevented the development of mood and cognitive deficits in mice when treatment was implemented immediately following the exposure. Moreover, when symptoms were already present, LDN/OSU-215111 still significantly ameliorated these deficits; impressively, benefits were sustained one month after treatment cessation, indicating disease modification. LDN/OSU-215111 effectively normalized hippocampal pathological changes. Overall, this study provides strong evidence that restoration of tripartite glutamatergic synapses by LDN/OSU-215111 is a potential therapy for Gulf War illness.

Novel Strategy for Designing Photochromic Ceramic: Reversible Upconversion Luminescence Modification and Optical Information Storage Application in the PbWO4:Yb3+, Er3+ Photochromic Ceramic.

Inorganic photochromic material is an available medium to obtain optical information storage. The photochromic property of the inorganic material is mainly from the defects of the host. However, the formation of defects in the host is uncontrollable, in particular, the revisable formation and removement of defects are difficult. Thus, there are few inorganic materials with the revisable photochromism upon the entire light stimulation. Therefore, it is an urgent need to find a suitable approach to design inorganic photochromic materials. Here, the photochromic PbWO4:Yb3+, Er3+ ceramic was designed with the help of valence state change of W6+ → W5+ and Pb2+ → Pb4+. Upon the 532 nm laser stimulation, the photochromism of the PbWO4:Yb3+, Er3+ ceramic was obtained based on the Pb2+ + hν (532 nm) → Pb4+ + 2e- and W6+ + e- + hν (532 nm) → W5+ reaction, resulting in the optical information writing. Under the stimulation of an 808 nm laser, the written optical information was erased based on the W5+ + hν (808 nm) → W6+ + e- and Pb4+ + 2e- + hν (808 nm) → Pb2+ reaction. In addition, the photochromism-induced upconversion emission modification was obtained in the PbWO4:Yb3+, Er3+ ceramic, realizing the effective and nondestructive reading out of optical information. The cyclic experiment demonstrated a good reproducibility of both photochromism and upconversion emission modification, exhibiting the potential application of the PbWO4:Yb3+, Er3+ ceramic as the optical data storage medium.

Somatic gene mutation signatures predict cancer type and prognosis in multiple cancers with pan-cancer 1000 gene panel.

Most cancers are caused by somatic mutations. Some common mutations in the same cancer type can form a "signature" to specifically predict the prognosis or to distinguish it from other cancers. In this study, 710 somatic cell mutations were identified in 142 cases, including digestive, lung and urogenital cancers, and the digestive cancers were further divided into liver, stomach, intestinal, esophageal and cardia cancer. The above mutations were located in 166 genes. In addition, a group of high-frequency mutation genes with specific characteristics were screened to form predictive signatures for each cancer. Verification using TCGA suggested that the signatures could predict the stages, progression-free survival, and overall survival of digestive, intestinal, and liver cancers (P < 0.05). The validation cases further confirmed the predictive role of digestive and liver cancers signatures in diagnosis and prognosis. Overall, this study established predictive signatures for different cancer systems and their subtypes. These findings enable a better understanding in cancer genome, and contribute to the personalized diagnosis and treatment.

Evaluation of industrial water use efficiency considering pollutant discharge in China.

China is facing severe pressure on its water resources and water environments. Calculating the industrial water efficiency of each province is an important index for the central government to evaluate local governments. In the traditional water resources evaluation index, the industrial water use efficiency and pollutant discharge are evaluated separately. In this paper, we collected industrial input data, output data and pollutant discharge data with a four-stage data envelopment analysis to calculate China's industrial water use efficiency with and without considering pollutant discharge, and then analyzed the factors influencing the industrial water use efficiency. The results show that the eastern coastal provinces of China have the highest water use efficiency and are less affected by pollutant discharge than other provinces. The industrial water use efficiency of the central and western provinces is lower than that of the other provinces, and the industrial water use efficiency in the central provinces is greatly affected by pollutant discharge. Factor endowment, economic development level, scientific and technological progress, industrial structure, proportion of foreign investment, water consumption per 10000 yuan of value-added by industry, industrial sewage treatment capacity and educational investment have a significant influence on the industrial water use efficiency of China. We suggest that the government strengthen the construction of sewage plants and other related infrastructure in central provinces when conducting the industrial transfer of heavy polluting enterprises.

Validation of the Chinese version of the Health Cognitions Questionnaire in Chinese college students.

PURPOSE: The cognitive behavioral model is considered the most comprehensive for explaining the pathogenesis of health anxiety (HA). The model proposes 4 dysfunctional beliefs that play a vital role in developing and sustaining HA: a) the likelihood of contracting or having an illness, b) awfulness of the illness, c) difficulty coping with illness, and d) inadequacy of medical services. The Health Cognitions Questionnaire (HCQ), widely used in English populations, was developed for assessing these core cognitions. As HA is a growing problem in China, we translated the HCQ into a Chinese version (CHCQ) and examined its psychometric properties. These core cognitions were compared among individuals with and without medical conditions. METHODS: A set of questionnaires that included the CHCQ and the Short Health Anxiety Inventory (SHAI) was used to gather data from 1,319 Chinese college students. After 4 weeks, 145 of the students completed the CHCQ again. The validity, reliability, and measurement invariance were evaluated among individuals with various medical conditions. RESULTS: The final CHCQ included 19 items. A 4-factor structure was well suited to the data. Good internal consistency (Cronbach's α for total score was 0.849, subscales ranged from 0.753 to 0.841), test-retest reliability (the interclass correlation coefficient for total score was 0.762, subscales ranged from 0.626 to 0.683), and criterion validity of the CHCQ were demonstrated. Measurement and structural invariance were established. Individuals with a diagnosed disease scored higher on the likelihood-of-illness subscale (Cohen's d =0.22, p < 0.01) than those without an illness. CONCLUSION: The CHCQ shows promise for the assessment of 4 core HA-related cognitions in the Chinese population.

Pyridazine-derivatives Enhance Structural and Functional Plasticity of Tripartite Synapse Via Activation of Local Translation in Astrocytic Processes.

Excitatory amino acid transporter 2 (EAAT2) is primarily located in perisynaptic astrocytic processes (PAP) where it plays a critical role in synaptic glutamate homeostasis. Dysregulation of EAAT2 at the translational level has been implicated in a myriad of neurological diseases. We previously discovered that pyridazine analogs can activate EAAT2 translation. Here, we sought to further refine the site and mechanism of compound action. We found that in vivo, compound treatment increased EAAT2 expression only in the PAP of astrocytes where EAAT2 mRNA also was identified. Direct application of compound to isolated PAP induced de novo EAAT2 protein synthesis, indicating that compound activates translation locally in the PAP. Using a screening process, we identified a set of PAP proteins that are rapidly up-regulated following compound treatment and a subset of these PAP proteins may be locally synthesized in the PAP. Importantly, these identified proteins are associated with the structural and functional capacity of the PAP, indicating compound enhanced plasticity of the PAP. Concomitantly, we found that pyridazine analogs increase synaptic protein expression in the synapse and enhance hippocampal long-term potentiation. This was not dependent upon compound-mediated local translation in neurons. This suggests that compound enhances the structural and functional capacity of the PAP which in turn facilitates enhanced plasticity of the tripartite synapse. Overall, this provides insight into the mechanism action site of pyridazine derivatives as well as the growing appreciation of the dynamic regulation and functional aspects of the PAP at the tripartite synapse.

Oroxyloside inhibits human glioma progression by suppressing proliferation, metastasis and inducing apoptosis related pathways.

Malignant glioma are linked to a high mortality rate. Therefore, it is necessary to explore and develop effective therapeutic strategy. Oroxyloside is a metabolite of oroxylin A. However, its inhibitory effects on cancer are little to be known. In the present study, we investigated the effects of oroxyloside on cell proliferation, migration, and apoptosis in vitro and in vivo in human glioma. The results indicated that oroxyloside significantly suppressed the proliferation of human glioma cells through inducing cell cycle arrest at G0/G1 phase through reducing Cyclin D1 and cyclin-dependent kinase 2 (CDK2) while enhancing p53 and p21 expressions. In addition, the migration of glioma cells was dramatically inhibited by oroxyloside in a dose-dependent manner, which was related to its modulation on extracellular matrix (ECM), as evidenced by up-regulated E-cadherin, and metastasis-associated protein 3 (MTA3), whereas down-regulated N-cadherin, Vimentin, Twist, alpha-smooth muscle actin (α-SMA) and Syndecan-2. Furthermore, oroxyloside treatment markedly induced apoptosis in glioma cells through improving Caspase-9, Caspase-3 and PARP cleavage, accompanied with high release of cytochrome c (Cyto-c) into cytoplasm and subsequently increase of apoptotic protease-activating factor 1 (Apaf-1). In vivo, oroxyloside administration significantly inhibited the glioma cell xenograft tumorigenesis through various signaling pathways, including suppression of Cyclin D1/CDK2 and ECM pathways, as well as potentiation of p53/p21 and Caspases pathways. Together, the findings above illustrated that oroxyloside, for the first time, was used as a promising candidate against human glioma.

Effect of Intravenous Dexmedetomidine During General Anesthesia on Acute Postoperative Pain in Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Dexmedetomidine has been shown to have an analgesic effect. However, no consensus was reached in previous studies. METHODS: Electronic databases such as PubMed, Embase, and Cochrane Central were searched for relevant randomized controlled trials. The relative risk and weighted mean difference (WMD) were used to analyze the outcomes. Random-effects model was used for meta-analysis. RESULTS: Compared with the normal saline group, patients using DEX showed a significantly decreased pain intensity within 6 hours [WMD=-0.93; 95% confidence interval (CI), -1.34 to -0.53) and at 24 hours after surgery (WMD=-0.47; 95% CI, -0.83 to -0.11). DEX usage significantly reduced the cumulative opioids consumption at 24 hours after surgery (WMD=-6.76; 95% CI, -10.16 to -3.35), decreased the rescue opioids consumption in postanesthesia care unit (WMD=-3.11; 95% CI, -5.20 to -1.03), reduced the risk of rescue analgesics (relative risk=0.49; 95% CI, 0.33-0.71), and the interval to first rescue analgesia was prolonged (WMD=34.93; 95% CI, 20.27-49.59). CONCLUSIONS: Intravenous DEX effectively relieved the pain intensity, extended the pain-free period, and decreased the consumption of opioids during postoperative recovery of adults in general anesthesia.

Linarin sensitizes tumor necrosis factor-related apoptosis (TRAIL)-induced ligand-triggered apoptosis in human glioma cells and in xenograft nude mice.

Tumor necrosis factor-related apoptosis-induced ligand (TRAIL) is reported as a promising anti-cancer therapeutic agent. Nevertheless, a variety of cancer cells, including human malignant glioma cells, are resistant to TRAIL treatment, indicating that it is necessary to find effective strategies to overcome the TRAIL resistance. Linarin (LIN), a natural flavonoid compound in Flos Chrysanthemi Indici (FCI), has been exhibited to exert various pharmacological activities, including anti-cancer. Here in our study, we found that non-cytotoxic doses of LIN (5µM) dramatically potentiated TRAIL (80ng/ml)-induced cytotoxicity (52.36±1.58%) and apoptosis (68.50±1.23%) using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and flow cytometry assays, respectively, in human glioma cells of U87MG. Apoptosis was evidenced by enhanced cleavage of Caspase-8/-9/-3 and poly (ADP-ribose) polymerase (PARP), and reduced anti-apoptotic proteins, including B-cell leukemia/lymphoma 2 (Bcl-2), mantle cell lymphoma (Mcl)-1, and Survivin. Moreover, both intrinsic and extrinsic apoptosis pathways were included in apoptosis induced by LIN and TRAIL co-treatment, along with high release of Cyto-c into cytoplasm and enhancement of fas-associated protein with death domain (FADD), death-inducing signaling complex (DISC), death receptor 4 (DR) 4 and DR5, respectively. Reactive oxygen species (ROS) generation, up to 39.86±2.32%, was also highly triggered by TRAIL and LIN combinational treatment, which was accompanied with high phosphorylation of c-Jun-N-terminal kinase (JNK). In vivo, TRAIL and LIN double treatment significantly reduced the tumor growth using xenograft tumor model through inducing apoptosis. We demonstrated that combining LIN with TRAIL treatments might be effective against TRAIL-resistant glioma cells through inducing apoptosis regulated by ROS generation.

Effect of Oxycodone Combined With Dexmedetomidine for Intravenous Patient-Controlled Analgesia After Video-Assisted Thoracoscopic Lobectomy.

OBJECTIVE: To investigate the effect of the combination of oxycodone and dexmedetomidine for patient-controlled analgesia (PCA) after video-assisted thoracoscopic (VATS) lobectomy. DESIGN: A prospective, randomized, double-blind, controlled trial. SETTING: Shandong Cancer Hospital and Institute in Jinan, China. PARTICIPANTS: Eighty-four patients with lung cancer undergoing VATS lobectomies were recruited. INTERVENTIONS: Patients were randomly assigned to one of the following two groups: oxycodone and dexmedetomidine (group OD) or oxycodone alone (group O). Before induction of anesthesia, patients in group OD received 0.5 µg/kg, dexmedetomidine diluted to 20 mL with physiologic saline and infused for 10 minutes intravenously. The PCA protocol was 50 mg of oxycodone and 0.05 µg/kg/h dexmedetomidine diluted to 100 mL. Patients in group O received 20 mL of physiologic saline infused for 10 minutes. Their PCA protocol consisted of 50 mg of oxycodone diluted to 100 mL. Intravenous PCA was used for postoperative analgesia (lasting for 48 h). MEASUREMENTS AND MAIN RESULTS: Pain at rest and during movement was assessed by a blinded observer using the Visual Analog Scale pain score (VAS) at 4, 6, 24, and 48 hours after surgery, and the level of sedation simultaneously was assessed using the Ramsay Sedation Scale. Total oxycodone consumption, requirements for rescue analgesia, side effects, and satisfaction with pain management were recorded within 48 hours after surgery. Eighty patients' data were analyzed at the end of the study (40 in each group). Visual Analog Scale scores decreased at 4, 6, and 24 hours at rest and during movement in group OD compared with group O (p<0.05). The level of patient satisfaction in group OD was significantly higher than that in group O (p<0.05). Oxycodone consumption in group OD was significantly lower than that in group O (p<0.001). Group O experienced more nausea and vomiting 6 hours after surgery than did group OD (p< 0.05). CONCLUSION: The combination of oxycodone and dexmedetomidine for PCA after VATS lobectomy can reduce oxycodone consumption, improve patient satisfaction, and provide better analgesia with fewer side effects (nausea and vomiting) compared with PCA with oxycodone alone.

[Transfection Efficiency of Ad5F11p-GFP on CIK and NK-92 Cells and Its Influence on Biological Characteristics].

OBJECTIVE: To study transfection efficiency of Ad5F11p-GFP and its influence on biological characteristics of CIK and NK-92 cells in order to predict the application of Ad5F11p vector in immunotherapy. METHODS: Two kinds of immune cells, cytokine-induced killer (CIK) cells and natural-killer (NK) cell line NK-92 cells, were transfected by Ad5F11p-GFP at different multiplicity of transfection (MOI), and untransfected immune cells were used as negative control. GFP expression was determined by flow cytometry, the cell morphology was observed with microscope, the cell proliferation was analyzed by trypan blue staining, specific cytotoxicity of NK-92 cells was determined by LDH assay. RESULTS: About 90% of transfection efficiency for NK-92 cells could be achieved at a MOI of 25, while the transfection efficiency for CIK was less than 40% at a MOI of 200. In addition, the transfection efficiency basically unchanged at the same MOI for 48 h and 96 h, and the immune cells transfected with the virus trended to form agglomeration, displaying slower proliferation, increase of IFN-γ release and enhancement of tumor killing activity. CONCLUSION: Ad5F11p- modified NK-92 shows a good prospect for adoptive immunotherapy.

Effect of Dexmedetomidine Alone for Intravenous Patient-Controlled Analgesia After Gynecological Laparoscopic Surgery: A Consort-Prospective, Randomized, Controlled Trial.

Gynecological laparoscopic surgery is minimally invasive compared with open surgical approaches, but postoperative pain is generally undermanaged. Pain management strategies related to the procedure-specific efficacy are needed. Many studies have shown that dexmedetomidine (DEX) has opioid-sparing properties. It is not clear whether DEX used alone for intravenous patient-controlled analgesia (PCA) could reduce postoperative pain after an invasive procedure. We hypothesized that DEX alone would reduce postoperative pain in women patients undergoing an elective gynecological laparoscopic procedure.This CONSORT-prospective randomized controlled clinical study aimed to investigate the effects of DEX alone for intravenous PCA after gynecological laparoscopic operation. Forty women patients scheduled for elective gynecological laparoscopy were enrolled into the study at Shandong Cancer Hospital and Institute and randomly allocated into two groups (n = 20 each). In the DEX group (group D), the intravenous PCA protocol was DEX 0.25 µg/kg/h diluted to 100 mL in 0.9% saline. In the fentanyl group (group F), the PCA protocol was fentanyl 20 µg/kg diluted to 100 mL in 0.9% saline. The primary outcome was the mean pain score on a visual analogue scale (VAS) at 6 hours after the operation. The secondary outcomes included the Ramsay sedation score, the incidence of postoperative nausea and vomiting (PONV), satisfaction with pain control, and time to recovery of gastrointestinal function.There were no significant differences in the patients' characteristics and intraoperative measurements (P > 0.05). No patients received rescue analgesic. The mean VAS scores at 6 hours post-operatively were not significantly different between the groups (P > 0.05). The incidence of PONV was less in group D than in group F (P < 0.05). The Ramsay sedation scores were not significantly between the groups (P > 0.05). Satisfaction with pain control was higher and time to recovery of gastrointestinal function was lower in group D (P < 0.05).DEX alone is effective for intravenous patient-controlled analgesia after gynecological laparoscopic surgery without a change in sedation and with fewer side effects, and this effect was associated with better satisfaction with postoperative pain control and earlier recovery of gastrointestinal function.

Effects of epidural analgesia with different concentrations of bupivacaine plus fentanyl on pain in patients undergoing thoracic surgery.

OBJECTIVE: To investigate and compared the efficacy and safety of epidural analgesia with different concentrations of bupivacaine plus fentanyl on pain in patients undergoing thoracic surgery. METHODS: 120 cases undergoing elective thoracic surgery were randomly divided into A, B, C and D four groups each with 30 cases, and they were treated with 0.25% (A group), 0.375% (B group), 0.50% (C group) and 0.75% (D group) bupivacaine plus fentanyl 0.4 mg. The pain conditions postoperative 4 h, 8 h, 12 h, 24 h and 48 h were evaluated by visual analogue scale (VAS). The PCA pressing numbers and incidence of adverse reactions were compared between the four groups. RESULTS: By postoperative 4 h, the VAS in D group were obviously lower than those in the other three groups (P all <0.05), and the other three groups showed no significances (P>0.05). However, the four groups showed no significant differences in VAS by postoperative 8 h, 12 h, 24 h and 48 h (P all >0.05). The incidences of respiratory depression in C and D groups were markedly higher than those in A and B groups (P all <0.05). CONCLUSIONS: 0.25%~0.375% bupivacaine plus fentanyl 0.4 mg using in epidural analgesia in patients undergoing thoracic surgery can lead to safe and effective analgesic effect.

A new luteolin triglycoside from Ficus ischnopoda leaves.

A new triglycoside flavone, luteolin-4'-O-α-l-rhamnopyranosyl-(1 → 6)-ß-d-glucopyranosyl-(1 → 3)-ß-d-glucopyranoside (1) was isolated from the leaves of Ficus ischnopoda, together with five known flavonoids (2-6) and seven known lignans (7-13). Their structures were elucidated on the basis of extensive spectroscopic analysis and comparison with literature data. Compounds 1-13 were reported in this plant for the first time. Compounds 1 and 3-6 exhibited significant anti-HSV-1 activity in vitro.

Characterization of the secondary binding sites of Maclura pomifera agglutinin by glycan array and crystallographic analyses.

The Maclura pomifera agglutinin (MPA) recognizes the T-antigen disaccharide Galß1,3GalNAc mainly through interaction of the α-GalNAc moiety with its primary site, but the interactions of the two flanking subsites A and B with aglycones and substituents other than Gal, respectively, are not well understood. We therefore characterized the specificity of MPA in more detail by glycan microarray analysis and determined the crystal structures of MPA without ligand and in complexes with Galß1,3GalNAc and p-nitrophenyl α-GalNAc. In both sugar complexes, pairs of ligands created inter-tetramer hydrogen-bond bridging networks. While subsite A showed increased affinity for hydrophobic aglycones, it also accommodated several sugar substituents. Notably, a GalNAc-O-tripeptide, a Tn-antigen mimic, showed lower affinity than these compounds in surface plasmon resonance (SPR) experiments. The glycan array data that showed subsite B accepted compounds in which the O3 position of the GalNAc was substituted with various sugars other than Gal, but substitutions at O6 led to inactivity. Additions to the Gal moiety of the disaccharide also had only small effects on reactivity. These results are all compatible with the features seen in the crystal structures.

Targeted therapy of respiratory syncytial virus by 2-5A antisense.

Respiratory syncytial virus is a leading cause of respiratory disease in infants, young children, immunocompromized patients, and the elderly. Previous work has shown that RNase L, an antiviral enzyme of the interferon system, can be recruited to cleave RSVgenomic RNA by attaching tetrameric 2' 5'-linked oligoadenylates (2 5A) to an antisense oligonucleotide complementary to repetitive intergenic sequences within the RSV genome (2 5A antisense). RBI034, a 2'-O-methyl RNA-modified analogue of the 2 5A anti-RSV compound, was found to have enhanced antiviral activity in cell culture studies while also cleaving RSV genomic RNA in an RNase L- and sequence-specific manner. RBI034s efficacy in suppressing RSV replication in cell culture is 50 to 100 times better than ribavirin, the only approved drug for RSV infection. Here we show that the activity of 2 SA antisense compound can be further enhanced by a combination treatment with interferon or ribavirin. The anti-RSV activity resulting from combination treatment is more potent than either treatment alone. We also demonstrate that RBI034 is effective against RSV in three different species: mice, cotton rats, and African green monkeys.

A convenient and sensitive fluorescence resonance energy transfer assay for RNase L and 2',5' oligoadenylates.

Interferon action against viruses is mediated in part through a ribonucleic acid (RNA) decay pathway known as the 2-5A system. Unusual 5'-triphosphorylated, 2',5'-linked oligoadenylates (2-5A) are produced in mammalian cells by interferon-inducible 2-5A synthetases (OAS) in response to viral double-stranded RNA. 2-5A activates a uniquely regulated endoribonuclease, RNase L, resulting in the cleavage of single-stranded viral and cellular RNAs, thus suppressing viral replication. In addition, RNase L was recently identified as a strong candidate for the hereditary prostate cancer 1 susceptibility allele. RNase L is ubiquitously expressed at basal levels in a wide range of mammalian cell types. Conventional RNase L assays, which can be inconvenient and cumbersome, typically involve cleavage of radioactively labeled RNA species or of endogenous ribosomal RNA. Here we describe a convenient, rapid, nonradioactive, and relatively inexpensive fluorescence resonance energy transfer (FRET) that may be used to accurately measure levels of either 2-5A or RNase L activity with a high degree of specificity and sensitivity. The RNA probe used in the FRET assay was designed based on a region of respiratory syncytial genomic RNA. We demonstrate the utility of our FRET assay with several novel biostable analogs of 2-5A.