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Objective: To investigate the pharmacokinetic characteristics of absorption, distribution, metabolism, and excretion in vivo after oral administration and sublingual venous injection of the small molecule IMM-H007 in hamsters. MATERIALS AND  METHODS: Pharmacokinetic characteristics, including absorption, distribution, metabolism, and excretion, were studied in vivo by LC-MS/MS after oral administration and sublingual venous injection of IMM-H007 in hamsters. Furthermore, IMM-H007 stability in artificial gastric juices, artificial intestinal juices, and Tris-HCl buffer was also analyzed., Results: There was no significant matrix or impurity interference in golden hamster whole blood as shown using MS/MS analysis to detect the existence of these substances. IMM-H007, Ml, and MP exhibited good linearity in the range of 1-500 ng/mL, 2-1000 ng/mL, and 10-5000 ng/mL, respectively. The matrix effect was 71.93-105.49%, and IMM-H007, M1, and MP were stable during the process of sample disposal. These results illustrate that the HPLC MS/MS analytic method is simple, reliable, and sensitive and exhibits high specificity and which meets the clinical pharmacokinetic requirements of IMM-H007. IMM-H007 is rapidly absorbed through the oral route in hamsters. The Cmax and AUC(0-t) of the Ml and MP metabolites in male and female hamsters were increased with increasing dosage and were proportional to the dose. In addition, T1/2 and MRT(0-t) were significantly prolonged with increasing dosage, exhibiting linear dynamic characteristics and no significant gender differences. Bioavailability in male and female golden hamsters after oral administration of IMM-H007 was calculated using the sum of Ml and MP, resulting in 6.97% and 8.95%, respectively. IMM-H007 and its metabolites were stable in Tris-HCl buffer, artificial gastric juices, and artificial intestinal juices., Conclusions: We provide an experimental basis for elucidating the material pharmacodynamics actions of IMM-H007 and predicting its potential drug interactions.

Successful spin injection into graphene makes it a competitive contender in the race to become a key material for quantum computation, or the spin-operation-based data processing and sensing. Engineering ferromagnetic metal (FM)/graphene heterojunctions is one of the most promising avenues to realise it, however, their interface magnetism remains an open question up to this day. In any proposed FM/graphene spintronic devices, the best opportunity for spin transport could only be achieved where no magnetic dead layer exists at the FM/graphene interface. Here we present a comprehensive study of the epitaxial Fe/graphene interface by means of X-ray magnetic circular dichroism (XMCD) and density functional theory (DFT) calculations. The experiment has been performed using a specially designed FM1/FM2/graphene structure that to a large extent restores the realistic case of the proposed graphene-based transistors. We have quantitatively observed a reduced but still sizable magnetic moments of the epitaxial Fe ML on graphene, which is well resembled by simulations and can be attributed to the strong hybridization between the Fe 3dz2 and the C 2pz orbitals and the sp-orbital-like behavior of the Fe 3d electrons due to the presence of graphene.

Objectives: To compare adverse effects, tolerability and efficacy of the tricyclic antidepressants (TCAs) amitriptyline and nortriptyline in management of neuropathic pain due to peripheral neuropathy (PN)., Materials & Methods: We performed a prospective open-label flexible-dosing comparison of monotherapy or adjuvant therapy using amitriptyline or nortriptyline in PN-associated neuropathic pain. Primary outcomes were quantitative adverse effects and discontinuation rates. Secondary outcomes assessed changes in pain severity, quality of life, disability, sleep efficacy, mood and anxiety, and global improvement. Assessments occurred at 3 and 6 months after initiation. Our hypothesis was that nortriptyline would have better tolerance than amitriptyline., Results: A total of 228 PN patients were enrolled approximately equally for monotherapy and adjuvant therapy. Adverse effects and discontinuation rates were similar between amitriptyline and nortriptyline interventions. Weight gain was more common with amitriptyline, while nortriptyline use was associated with greater prevalence of dry mouth. Secondary outcome measures were similar in both groups, demonstrating improvement from baseline., Conclusions: Amitriptyline and nortriptyline are equivalent for overall adverse effects and discontinuation rates. Either TCA should be equally considered for use in neuropathic pain due to PN. When used as monotherapy or as part of adjuvant therapy, either TCA can be expected to provide approximately 23-26% visual analog scale pain reduction if tolerated. Discontinuations due to inefficacy or adverse effects can be anticipated in 26-37% of patients initiated on either TCA for PN-associated neuropathic pain., (© 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

This study investigated the nucleotide sequences and tissue expression levels of genes relating to the ovulation rate in Yunling black goats, a famous Yunnan province, China, local breed with low fecundity. Five genes, FSHB, FSHR, BMP15, BMPR1B, and ESR2, were investigated; the complete cDNA sequences of these genes were 390, 2088, 1185, 1509, and 1585 bp, respectively, and compared with Boer goats (a more fecund breed), the sequence identities were 99%, 99%, 99%, 100%, and 99%, respectively. There were two base differences in FSHB and BMP15, four in FSHR, and three in ESR2. There were fewer follicles and oocytes in Yunling black goats than in Boer goats. Expression levels of FSHB, FSHR, and BMP15 genes in Yunling black goats were lower, and expression levels of BMPR1B and ESR2 genes were higher. Serum FSH content was lower in Yunling black goats, but serum estrogen content was higher. Protein expression levels of FSHR, BMP15, BMPR1B, and ESR2 in ovary and pituitary correlated positively with gene mRNA expression levels. In Yunling black goats, the mRNA expression levels of FSHB, FSHR, and BMP15 positively correlated with litter size, but those of BMPR1B and ESR2 correlated negatively. Together, base changes and variations in mRNA and protein expression levels of genes relating to the ovulation rate result in low fecundity in the Yunling black goat. Reduced BMP15 and FSHR levels may be related to the observed fewer oocytes and, consequently, fewer follicles.

Amyotrophic lateral sclerosis (ALS) is a fatal neuromuscular disorder in which motor neurons may be targeted by oxidative and nitrergic stress without sufficient compensation by intrinsic support mechanisms. In this work, we addressed two key tenets of this hypothesis for the pathogenesis of ALS. Using superoxide dismutase (SOD) 1G93A mice, we studied the impact of reduction of nitrergic stress within the CNS with the use of a broad spectrum nitric oxide synthase (NOS) inhibitor, NG-nitro-l-arginine methyl ester. A separate cohort of SOD1G93A mice received direct insulin neurotrophic support, ligating receptors expressed upon motor neurons, to attempt protection against neuronal and functional motor dropout. For direct access, we used a novel form of intranasal delivery that provides peak concentration levels in the CNS within 1 h of delivery without systemic side effects at doses which previously rescued retrograde loss of motor axons after axotomy. To identify even minor impacts of these interventions on the outcome, we utilized an intensive program of serial behavioral and electrophysiological testing weekly, combined with endpoint quantitative morphometry and molecular analysis. This intensive evaluation enhanced our knowledge of the time course in SOD1G93A mice and impact of the SOD1G93A mutation upon motor neurons and their function. Neither intervention had even minimal impact upon slowing progression of disease in SOD1G93A mice. Our data argue against significant roles for nitrergic stress in promoting motor neuron loss and the importance of alternative neurotrophic support mechanisms that might support motor neurons and prevent disease progression in SOD1G93A mice.

The regeneration of adult peripheral neurons after transection is slow, incomplete and encumbered by severe barriers to proper regrowth. The role of RHOA GTPase has not been examined in this context. We examined the expression, activity and functional role of RHOA GTPase and its ROK effector, inhibitors of regeneration, during peripheral axon outgrowth. We used qRT-PCR, quantitative immunohistochemistry, and assays of RHOA activation to examine expression in sensory neurons of rats with sciatic transection injuries. In vitro, we exposed dissociated adult sensory neurons, not grown on inhibitory substrates, to a RHOA-ROK inhibitor HA-1077 and measured neurite initiation and outgrowth. In vivo, we exposed early regenerating axons and Schwann cells directly to HA-1077 in a conduit connecting the proximal and distal stumps of transected sciatic nerves. Intact adult dorsal root ganglia sensory neurons expressed RHOA and ROK 1 mRNAs and protein and there were rises in RHOA after injury. Activated GTP-bound RHOA, undetectable in intact ganglia, was dramatically upregulated in both neurons and axons after injury. Adult rat sensory neurons in vitro demonstrated a dose-related increase in the initiation of neurite outgrowth, and in the proportion with long neurites when they were exposed to a ROK antagonist. Regenerative bridges that were directly exposed to the ROK inhibitor had a dose-related rise in the extent and distance of in vivo axon and partnered Schwann cell regrowth within them. RHOA activation and signaling are features of adult peripheral axon regeneration within its own milieu, independent of myelin. Inhibition of its activation may benefit peripheral axon lesions.

Erythropoietin (EPO) and its receptor (EPO-R), mediate neuroprotection from axonopathy and apoptosis in the peripheral nervous system (PNS). We examined the impact and potential mechanisms of local EPO signaling on regenerating PNS axons in vivo and in vitro. As a consequence of injury, peripheral nerve axons and DRG neurons have a marked increase in the expression of EPO and EPO-R. Local delivery of EPO via conduit over 2 weeks to rat sciatic nerve following crush injury increased the density and maturity of regenerating myelinated axons growing distally from the crush site. In addition, EPO also rescued retrograde degeneration and atrophy of axons. EPO substantially increased the density and intensity of calcitonin gene-related peptide (CGRP) expression within outgrowing axons. Behavioral improvements in sensorimotor function also occurred in rats exposed to near nerve EPO delivery. EPO delivery led to decreased nuclear factor kappaB (NFkB) activation but increased phosphorylation of Akt and STAT3 within nerve and dorsal root ganglia neurons indicating rescue from an injury phenotype. Spinal cord explant studies also demonstrated a similar dose-dependent effect of EPO upon motor axonal outgrowth. Local EPO signaling enhances regenerating peripheral nervous system axons in addition to its known neuroprotection. Exogenous EPO may have a therapeutic role in a large number of peripheral nerve diseases through its impact on regeneration.

Growth factor receptor-bound protein 2 (Grb2) is an adapter protein involved in the Ras-dependent signaling pathway that plays an important role in human cancers initiated by oncogenic receptors. Grb2 is constituted by one Src homology 2 domain surrounded by two SH3 domains, and the inhibition of the interactions produced by these domains could provide an antitumor approach. In evaluating chemical libraries, to search for potential Grb2 inhibitors, it was necessary to elaborate a rapid test for their screening. We have developed, first, a batch method based on the use of an affinity column bearing a Grb2-SH3 peptide ligand to isolate highly purified Grb2. We subsequently describe a very rapid 96-well screening of inhibitors based on a simple competition between purified Grb2 and a peroxidase-coupled proline-rich peptide.

Recently a strong positive association between schizophrenia and Notch4 has been reported. Both individual markers and haplotypes showed association with the disease, with five markers (three microsatellites and two SNPs) being tested. In order to test this finding we genotyped these markers in the Han Chinese population using a sample of 544 cases and 621 controls as well as >300 trios. Analysis of allele, genotype and haplotype frequencies in both samples showed no association between the markers and the disease. Our results would indicate that a significant role for the Notch4 gene in schizophrenia can be ruled out in the Han Chinese. However, similar studies are necessary in the Caucasian population as linkage disequilibrium arrangements and founder effects may differ between these two populations.

In the vitamin K-dependent protein family, only protein S (PS) contains a thrombin-sensitive region (TSR), located between the domain containing the gamma-carboxyglutamic acid and the first epidermal growth factor-like domain. To better define the role of TSR in the PS molecule, we expressed a recombinant human PS (rHPS) and its analogue lacking TSR (rTSR-less), and prepared factor Xa- and thrombin-cleaved rHPS. A peptide reproducing TSR (TSR-peptide) was also synthesized in an attempt to obtain direct evidence of the domain involvement in PS anticoagulant activity. In a coagulation assay, both rTSR-less and factor Xa-cleaved PS were devoid of activated protein C cofactor activity. The TSR-peptide did not inhibit rHPS activity, showing that TSR must be embedded in the native protein to promote interaction with activated protein C. The binding of rHPS to activated platelets and to phospholipid vesicles was not modified after factor Xa- or thrombin-mediated TSR cleavage, whereas the binding of rTSR-less was markedly reduced. This suggested a role for TSR in conferring to PS a strong affinity for phospholipid membranes. TSR-peptide did not directly bind to activated platelets or compete with rHPS for phospholipid binding. The results of the present study show that TSR may not interact directly with membranes, but probably constrains the gamma-carboxyglutamic acid-rich domain in a conformation allowing optimal interaction with phospholipids.

Objective: To explore the activity of heme oxygenase and immunolocate the enzyme in the adult worms of Schistosoma japonicum., Methods: Microsomal protein was isolated from the homogenate of adult S. japonicum, heme degradation and effect of different pH conditions and buffers on degrading reaction were investigated by incubating microsomal protein with hemin. The slices of whole worm and cells of S. japonicum were prepared, distribution of HO in schistosome was studied by immunofluorescent and alkaline phosphatase(AP)-immunocytochemical assays., Results: Microsomal protein of adult worms can degrade the heme in vitro, the activity being 56.7 nmol bilirubin/(mg.min). The optimal pH was 8.7. Immunofluorescent and AP-immunocytochemical assays revealed that the HO distributed dispersively in the worm, and located in cytoplasm., Conclusion: The presence of HO was firstly proved in S. japonicum.

Phosphopeptide prodrugs bearing two S-acyl-2-thioethyl (SATE) biolabile phosphate protections were developed. They are capable to inhibit the Shc/Grb2 interaction and MAP kinases (ERK1 and ERK2) phosphorylation in cellular assay. The S-acetyl-2-thioethyl (MeSATE) analogue showed an IC50 of 1 microM in the inhibition of the colony formation of tumor cell line NIH3T3/HER2.

A series of small peptides with the sequence mAZ-pTyr-Xaa-Asn-NH(2), where Xaa denotes alpha-methylphosphotyrosine or its carboxylic mimetics, were synthesized as inhibitors of the Grb2 SH2 domain. Peptide 3 with (alpha-Me)pTyr as Xaa has the highest affinity for Grb2 (K(d) = 3 +/- 1 nM) and exhibits to date the best inhibitory activity (IC(50) = 11 +/- 1 nM) to displace PSpYVNVQN-Grb2 interaction in an ELISA test. The lower affinities of peptides with (alpha-Me)Tyr, (alpha-Me)Phe(4-CO(2)H), or (alpha-Me)Phe(4-CH(2)CO(2)H) as Xaa demonstrate the importance of a double charged phosphate group at the pY+1 position. Molecular modeling showed additional hydrogen bond interactions provided by the (alpha-Me)pTyr residue with the Grb2 SH2 domain. These results thus show that the effect of hydrophobic pY+1 residues, initially put forth to increased the binding affinities, can be further enhanced by a (-Me)pTyr residue which has both hydrophobic and hydrophilic properties.

With the aim of interrupting the growth factor-stimulated Ras signaling pathway at the level of the Grb2-Sos interaction, a peptidimer, made of two identical proline-rich sequences from Sos linked by a lysine spacer, was designed using structural data from Grb2 and a proline-rich peptide complexed with its SH3 domains. The peptidimer affinity for Grb2 is 40 nM whereas that of the monomer is 16 microM, supporting the dual recognition of both Grb2 SH3 domains by the dimer. At 50 nM, the peptidimer blocks selectively Grb2-Sos complexation in ER 22 (CCL 39 fibroblasts overexpressing epidermal growth factor receptor) cellular extracts. The peptidimer specifically recognizes Grb2 and does not interact with PI3K or Nck, two SH3 domain-containing adaptors. The peptidimer was modified to enter cells by coupling to a fragment of Antennapedia homeodomain. At 10 microM, the conjugate inhibits the Grb2-Sos interaction (100%) and MAP kinase (ERK1 and ERK2) phosphorylation (60%) without modifying cellular growth of ER 22 cells. At the same concentration, the conjugate also inhibits both MAP kinase activation induced by nerve growth factor or epidermal growth factor in PC12 cells, and differentiation triggered by nerve growth factor. Finally, when tested for its antiproliferative activity, the conjugate was an efficient inhibitor of the colony formation of transformed NIH3T3/HER2 cells grown in soft agar, with an IC50 of around 1 microM. Thus, the designed peptidimers appear to be interesting leads to investigate signaling and intracellular processes and for designing selective inhibitors of tumorigenic Ras-dependent processes.

The effect of merocyanine 540 (Mc 540) mediated photoirradiation on both neoplastic and normal hemopoietic progenitor cells was studied. Bone marrow (BM) cells from children with acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML) at initial diagnosis, ALL in remission, neuroblastoma and normal children as well as cells of Reh-6 and HL-60 cell lines were incubated with Mc 540 in the presence of human albumin (HA) and exposed to different argon laser 514 nm doses. Cell survival was estimated using Trypan Blue supravital stain following a 24-h incubation and leukemic cell lines were studied in continuous cell cultures of 4 weeks duration. Our results showed that HA protects normal BM cells from Mc 540 mediated phototoxicity. A 99.9999% inhibition of Reh-6 and HL-60 was noted at irradiation doses where the corresponding mean survival of normal BM cells was 77.4 +/- 12 and 70.3 +/- 10%, respectively. BM leukemic cells from children with ALL and AML were also very sensitive to Mc 540 photoirradiation in contrast to neuroblastoma cells where only a three-fold reduction was observed. Finally, the survival of normal BM progenitors was 38% for colony forming unit erythroid CFU-E, 37% for burst forming unit erythroid BFU-E, 55% for CFU-GM and 29% for CFU-GEMM. In conclusion it seems that Mc 540 mediated photoirradiation in neoplastic cells exerts selective cytotoxicity and can be used in ex vivo purging of malignant cells in BM.

We previously showed that the oxidation of branched-chain amino acids is increased in rats treated with clofibrate [Paul and Adibi (1980) J. Clin. Invest. 65, 1285-1293]. Two subsequent studies have reported contradictory results regarding the effect of clofibrate treatment on gene expression of branched-chain keto acid dehydrogenase (BCKDH) in rat liver. Furthermore, there has been no previous study of the effect of clofibrate treatment on gene expression of BCKDH kinase, which regulates the activity of BCKDH by phosphorylation. The purpose of the present study was to investigate the above issues. Clofibrate treatment for 2 weeks resulted in (a) a 3-fold increase in the flux through BCKDH in mitochondria isolated from rat liver, and (b) a modest but significant increase in the activity of BCKDH. However, clofibrate treatment had no significant effect on the mass of E1 alpha, E1 beta, and E2 subunits of BCKDH or the abundance of mRNAs encoding these subunits. On the other hand, clofibrate treatment significantly reduced the activity, the protein mass and the mRNA levels of BCKDH kinase in the liver. In contrast to the results obtained in liver, clofibrate treatment had no significant effect on any of these parameters of BCKDH kinase in the skeletal muscle. In conclusion, our results show that clofibrate treatment increases the activity of BCKDH in the liver and the mechanism of this effect is the inhibition of gene expression of the BCKDH kinase.

The present study demonstrates that dexamethasone and 8-(4-chlorophenylthio)adenosine 3',5'-monophosphate (CPT-cAMP), a cAMP analog, increase the substrate flux through branched-chain keto acid dehydrogenase (BCKDH) in primary rat hepatocytes cultured in defined medium. Maximum response (2.7-fold increase in flux) was observed when hepatocytes were cultured with 1 microM dexamethasone plus 50 microM CPT-cAMP for 24 h. This increase in the flux rate was accompanied by significant increases in both the basal and total activities of BCKDH (2.2- and 2.0-fold, respectively), without any significant change in the activity state of this enzyme. The increase in BCKDH activity was the result of increased protein mass of E1 alpha (3.2-fold), E1 beta (2.9-fold), and E2 (1.6-fold) subunits of BCKDH, indicating that E2 is the limiting subunit for the expression of BCKDH. The relative abundance of mRNAs encoding the E1 alpha, E1 beta, and E2 subunits of BCKDH increased by 7.4-, 21.7-, and 4.8-fold, respectively. We conclude that increased flux through BCKDH in hepatocytes cultured with dexamethasone and CPT-cAMP is due to increased expression of BCKDH subunit genes. However, nonstoichiometric expression of individual subunits and the corresponding mRNAs suggests regulation of BCKDH also at translational and post-translational steps.

A series of indicators, including serum lysozyme activity, G-banding chromosome aberration (G-banding CA) analysis, sister chromatid exchanges (SCEs), chromosome aberration (CA), T-lymphocyte transformation rate (TcTR), gamma-GT, GPT and AKP, were employed in the present survey among occupationally vinyl chloride (VC) exposed workers and inhabitants living in VC polluted area in a polyvinyl chloride (PVC) factory. The results showed that the serum lysozyme (S-LZM) activities in Group 3 (adult inhabitants exposed to 0.20 mg/m3 VC for at least 8 years), Group 2 (workers exposed to 4.1 mg/m3 for at least 7 years occupationally), Group 1 (workers exposed to 25.7 mg/m3 for at least 2 years) were significantly higher than control. G-banding CA analysis showed that the total chromosome breakage rates in both Groups 1 and 2 were higher, but no difference existed between Group 3 and control. Only Group 1 was observed having higher SCEs, CA level and lower TcTR than control. AKP levels in Groups 1 and 2 were higher than control, but no gamm-GT and GPT differences were found among groups. The study also suggests that G-banding CA analysis is more sensitive than CA and SCEs.

In recent years considerable emphasis has been placed on the hypothesis that enhancement of GABA transmission could be beneficial in some types of epilepsy. The alpha-(aryl)-4-morpholineacetonitrile obtained by the interaction of aryl aldehydes, morpholine and potassium cyanide, have been used to synthesize 3-(aroyl)-propionic acids and esters by 1,4-additions to acrylonitrile or acrylic ester. 3-(Aroyl) propionic acids reacting with hydrazine can yield 6-aryl-4,5-dihydro-3(2H) pyridazinones which are dehydrogenated by bromine (via bromination dehydrobromination) to give 6-aryl-3(2H) pyridazinones. The latter compounds were converted into 3-(N-GABA)-6-(substitutedphenyl) pyridazines and 3-(N-butyryllactamyl)-6-(substitutedphenyl) pyridazines by the chlorination (by means of phosphorus oxychloride) and then reaction with GABA. By this method seventeen 3-GABA derivatives of 6-(substituted-phenyl)pyridazines were synthesized. The anticonvulsant activity (MES) of these compounds were also tested. 3-(N-GABA)-6-(2',4'-dichloro)phenylpyridazine; potent anticonvulsant (ED50 = 21.05 mg/kg).

In searching for effective anticonvulsant agent fourteen 6-(substituted-phenyl)-4,5-dihydro-3 (2H) pyridazinones and fifteen 6-(substitutedphenyl)-3 (2H) pyridazinones have been synthesized and screened in mice for their ability to antagonize maximal electroshock seizure (MES). The ED50 values showed that 6-(2',4'-dichlorophenyl)-3 (2H) pyridazinone was the most potent anticonvulsant in these compounds. The structure--activity relationships in these two series were examined. We came to the conclusion that the higher is the hydrophobic parameter pi of the substituent on phenyl ring, the more potent anticonvulsant is the compound. And also, only the compounds with an electronwithdrawing substituent on the phenyl ring exhibited appreciable anticonvulsant activity.

By injecting Naloxone, the T-lymphocyte transformation was reduced markedly. When the Naloxone plus electro-acupuncture were used together, it was not reduced but was still lower than it was when only electro-acupuncture was used. This explained why Naloxone could reverse the function by which electro-acupuncture promoted the T-lymphocyte transformation, and the endogenous opioid in the brain promoted the immune reaction. Through promoting the release of the endogenous opioid in the brain, electro-acupuncture raised the T-lymphocyte transformation function. Using electro-acupuncture when naloxone antagonized morphine, the T-lymphocyte transformation function was still promoted markedly. The mechanism could be that electro-acupuncture excited the function of the endogenous opioid system in the brain. In acupuncture immune reaction, the relationship between the endogenous opioid and catecholaminergic systems was explored.