WorldWideScience

Sample records for type benzodiazepine binding

  1. Gamma-aminobutyric acid-modulated benzodiazepine binding sites in bacteria

    International Nuclear Information System (INIS)

    Lummis, S.C.R.; Johnston, G.A.R.; Nicoletti, G.; Holan, G.

    1991-01-01

    Benzodiazepine binding sites, which were once considered to exist only in higher vertebrates, are here demonstrated in the bacteria E. coli. The bacterial [ 3 H]diazepam binding sites are modulated by GABA; the modulation is dose dependent and is reduced at high concentrations. The most potent competitors of E.Coli [ 3 H]diazepam binding are those that are active in displacing [ 3 H]benzodiazepines from vertebrate peripheral benzodiazepine binding sites. These vertebrate sites are not modulated by GABA, in contrast to vertebrate neuronal benzodiazepine binding sites. The E.coli benzodiazepine binding sites therefore differ from both classes of vertebrate benzodiazepine binding sites; however the ligand spectrum and GABA-modulatory properties of the E.coli sites are similar to those found in insects. This intermediate type of receptor in lower species suggests a precursor for at least one class of vertebrate benzodiazepine binding sites may have existed

  2. In vivo labelling in several rat tissues of 'peripheral type' benzodiazepine binding sites

    Energy Technology Data Exchange (ETDEWEB)

    Benavides, J.; Guilloux, F.; Rufat, P.; Uzan, A.; Renault, C.; Dubroeucq, M.C.; Gueremy, C.; Le Fur, G. (Pharmuka Laboratoires, 92 - Gennevilliers (France))

    1984-03-16

    'Peripheral type' benzodiazepine binding sites in several rat tissues were labelled by intravenous injection of (/sup 3/H)PK 11195 and (/sup 3/H)RO5-4864. Binding was saturable in all tissues studied and regional distribution paralleled the in vitro binding. A similar potency order of displacing compounds was found in vivo and in vitro PK 11195 > PK 11211 > RO5-4864 > diazepam > dipyridamole > clonazepam. These results demonstrate the feasibility of using this technique to examine the effects of pharmacological manipulation on the binding sites in their native state. However, some properties (broader maximum during time course, higher percentage of particulate binding in the brain and independence of temperature) make (/sup 3/H)PK 11195 the most suitable ligand for this kind of studies.

  3. Peripheral-type benzodiazepine receptors in the central nervous system: localization to olfactory nerves.

    Science.gov (United States)

    Anholt, R R; Murphy, K M; Mack, G E; Snyder, S H

    1984-02-01

    Binding levels of [3H]Ro5-4864, a ligand selective for peripheral-type benzodiazepine receptors, are substantially higher in homogenates of the olfactory bulb than in the rest of the brain. Among peripheral tissues evaluated, high levels of [3H]Ro5-4864 binding are found in the nasal epithelium. Drug displacement studies show that these binding sites are pharmacologically of the peripheral type. Their presence in the nasal epithelium and in the olfactory bulb can be demonstrated in several different mammalian species. Autoradiographic studies of murine nose reveal a bipolar staining pattern around the cell bodies of the olfactory receptor cells, suggesting the presence of peripheral-type benzodiazepine receptors on both processes of these bipolar neurons. In the brain a high density of [3H]Ro5-4864 binding sites occurs in the nerve fiber and glomerular layers of the olfactory bulb. Throughout the rest of the brain [3H]Ro5-4864-associated silver grains are diffusely distributed with intense staining over the choroid plexus and along the ependymal linings of the ventricles. Both the distribution and the ontogenic development of the peripheral-type benzodiazepine receptors differ from the central-type receptors. Intranasal irrigation with 5% ZnSO4 results in a 50% reduction of peripheral-type benzodiazepine receptors in the olfactory bulb without affecting the density of central-type benzodiazepine receptors. Thus, [3H]Ro5-4864 binding sites in the olfactory bulb appear in large part to be localized to olfactory nerves which originate in the nasal epithelium.

  4. Memory Effects of Benzodiazepines: Memory Stages and Types Versus Binding-Site Subtypes

    Directory of Open Access Journals (Sweden)

    Miroslav M. Savic

    2005-01-01

    Full Text Available Benzodiazepines are well established as inhibitory modulators of memory processing. This effect is especially prominent when applied before the acquisition phase of a memory task. This minireview concentrates on the putative subtype selectivity of the acquisition-impairing action of benzodiazepines. Namely, recent genetic studies and standard behavioral tests employing subtype-selective ligands pointed to the predominant involvement of two subtypes of benzodiazepine binding sites in memory modulation. Explicit memory learning seems to be affected through the GABAA receptors containing the α1 and α5 subunits, whereas the effects on procedural memory can be mainly mediated by the α1 subunit. The pervading involvement of the α1 subunit in memory modulation is not at all unexpected because this subunit is the major subtype, present in 60% of all GABAA receptors. On the other hand, the role of α5 subunits, mainly expressed in the hippocampus, in modulating distinct forms of memory gives promise of selective pharmacological coping with certain memory deficit states.

  5. Radioligands for PET studies of central benzodiazepine receptors and PK (peripheral benzodiazepine) binding sites -current status

    International Nuclear Information System (INIS)

    Pike, V.W.; Osman, S.; Shah, F.; Turton, D.R.; Waters, S.L.; Crouzel, C.; Nutt, D.J.

    1993-01-01

    The status of the radiochemical development and biological evaluation of radioligands for PET studies of central benzodiazepine (BZ) receptors and the so-called peripheral benzodiazepine binding sites, here discriminated and referred to as PK binding sites, is reviewed against current pharmacological knowledge, indicating those agents with present value and those with future potential. Practical recommendations are given for the preparation of two useful radioligands for PET studies, [N-methyl- 11 C]flumazenil for central BZ receptors, and [N-methyl- 11 C]PK 11195 for PK binding sites. Quality assurance and plasma metabolite analysis are also reviewed for these radioligands and practical recommendations are given on methodology for their performance. (Author)

  6. Benzodiazepine receptor binding in vivo with (/sup 3/)-Ro 15-1788

    Energy Technology Data Exchange (ETDEWEB)

    Goeders, N.E.; Kuhar, M.J.

    1985-07-29

    In vivo benzodiazepine receptor binding has generally been studied by ex vivo techniques. In this investigation, the authors identify the conditions where (/sup 3/H)-Ro 15-1788 labels benzodiazepine receptors by true in vivo binding, i.e. where workable specific to nonspecific ratios are obtained in intact tissues without homogenization or washing. (/sup 3/H)-Flunitrazepam and (/sup 3/H)-clonazepam did not exhibit useful in vivo receptor binding. 39 references, 5 figures, 1 table.

  7. High density of benzodiazepine binding sites in the substantia innominata of the rat

    International Nuclear Information System (INIS)

    Sarter, M.; Schneider, H.H.

    1988-01-01

    In order to study the neuronal basis of the pharmacological interactions between benzodiazepine receptor ligands and cortical cholinergic turnover, we examined the regional distribution of specific benzodiazepine binding sites using in vitro autoradiography. In the basal forebrain, the substantia innominata contained a high density of [ 3 H]lormetazepam (LMZ) binding sites (Bmax = 277 fmol/mg tissue; Kd = 0.55 nM). The label could be displaced by diazepam (IC50 = 100 nM), the benzodiazepine receptor antagonist beta-carboline ZK 93426 (45 nM) and the partial inverse agonist beta-carboline FG 7142 (540 nM). It is hypothesized that the amnesic effects of benzodiazepine receptor agonists are exerted through benzodiazepine receptors which are situated on cholinergic neurons in the substantia innominata and are involved in a tonic inhibition of cortical acetylcholine release. The benzodiazepine receptor antagonist ZK 93426 may exert its nootropic effects via benzodiazepine receptors in the substantia innominata and, consequently, by disinhibiting cortical acetylcholine release

  8. 1-Methyl-beta-carboline (harmane), a potent endogenous inhibitor of benzodiazepine receptor binding.

    Science.gov (United States)

    Rommelspacher, H; Nanz, C; Borbe, H O; Fehske, K J; Müller, W E; Wollert, U

    1980-10-01

    The interaction of several beta-carbolines with specific [3H]-flunitrazepam binding to benzodiazepine receptors in rat brain membranes was investigated. Out of the investigated compounds, harmane and norharmane were the most potent inhibitors of specific [3H]-flunitrazepam binding, with IC50-values in the micromolar range. All other derivatives, including harmine, harmaline, and several tetrahydroderivatives were at least ten times less potent. Harmane has been previously found in rat brain and human urine, so it is the most potent endogenous inhibitor of specific [3H]-flunitrazepam binding known so far, with a several fold higher affinity for the benzodiazepine receptor than inosine and hypoxanthine. Thus, we suggest that harmane or other related beta-carbolines could be potential candidates as endogenous ligands of the benzodiazepine receptor.

  9. Enhancement of GABAergic transmission by zolpidem, an imidazopyridine with preferential affinity for type I benzodiazepine receptors.

    Science.gov (United States)

    Biggio, G; Concas, A; Corda, M G; Serra, M

    1989-02-28

    The effect of zolpidem, an imidazopyridine derivative with high affinity at the type I benzodiazepine recognition site, on the function of the GABAA/ionophore receptor complex was studied in vitro. Zolpidem, mimicking the action of diazepam, increased [3H]GABA binding, enhanced muscimol-stimulated 36Cl- uptake and reduced [35S]TBPS binding in rat cortical membrane preparations. Zolpidem was less effective than diazepam on the above parameters. Zolpidem induced a lower increase of [3H]GABA binding (23 vs. 35%) and muscimol-stimulated 36Cl- uptake (22 vs. 40%) and a smaller decrease of [35S]TBPS binding (47 vs. 77%) than diazepam. The finding that zolpidem enhanced the function of GABAergic synapses with an efficacy qualitatively and quantitatively different from that of diazepam suggests that this compound is a partial agonist at the benzodiazepine recognition site. Thus, our results are consistent with the view that the biochemical and pharmacological profile of a benzodiazepine recognition site ligand reflects its efficacy to enhance GABAergic transmission. Whether the preferential affinity of zolpidem at the type I site is involved in its atypical biochemical and pharmacological profile remains to be clarified.

  10. Mitochondrial benzodiazepine receptors regulate steroid biosynthesis

    International Nuclear Information System (INIS)

    Mukhin, A.G.; Papadopoulos, V.; Costa, E.; Krueger, K.E.

    1989-01-01

    Recent observations on the steroid synthetic capability within the brain open the possibility that benzodiazepines may influence steroid synthesis in nervous tissue through interactions with peripheral-type benzodiazepine recognition sites, which are highly expressed in steroidogenic cells and associated with the outer mitochondrial membrane. To examine this possibility nine molecules that exhibit a greater than 10,000-fold difference in their affinities for peripheral-type benzodiazepine binding sites were tested for their effects on a well-established steroidogenic model system, the Y-1 mouse adrenal tumor cell line. 4'-Chlorodiazepam, PK 11195, and PK 14067 stimulated steroid production by 2-fold in Y-1 cells, whereas diazepam, flunitrazepam, zolpidem, and PK 14068 displayed a lower (1.2- to 1.5-fold) maximal stimulation. In contrast, clonazepam and flumazenil did not stimulate steroid synthesis. The potencies of these compounds to inhibit 3 H-labeled PK 11195 binding to peripheral-type benzodiazepine recognition sites correlated with their potencies to stimulate steroid production. Similar findings were observed in bovine and rat adrenocortical cell preparations. These results suggest that ligands of the peripheral-type benzodiazepine recognition site acting on this mitochondrial receptor can enhance steroid production. This action may contribute specificity to the pharmacological profile of drugs preferentially acting on the benzodiazepine recognition site associated with the outer membrane of certain mitochondrial populations

  11. Mitochondrial benzodiazepine receptors regulate steroid biosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Mukhin, A.G.; Papadopoulos, V.; Costa, E.; Krueger, K.E. (Georgetown Univ. School of Medicine, Washington, DC (USA))

    1989-12-01

    Recent observations on the steroid synthetic capability within the brain open the possibility that benzodiazepines may influence steroid synthesis in nervous tissue through interactions with peripheral-type benzodiazepine recognition sites, which are highly expressed in steroidogenic cells and associated with the outer mitochondrial membrane. To examine this possibility nine molecules that exhibit a greater than 10,000-fold difference in their affinities for peripheral-type benzodiazepine binding sites were tested for their effects on a well-established steroidogenic model system, the Y-1 mouse adrenal tumor cell line. 4{prime}-Chlorodiazepam, PK 11195, and PK 14067 stimulated steroid production by 2-fold in Y-1 cells, whereas diazepam, flunitrazepam, zolpidem, and PK 14068 displayed a lower (1.2- to 1.5-fold) maximal stimulation. In contrast, clonazepam and flumazenil did not stimulate steroid synthesis. The potencies of these compounds to inhibit {sup 3}H-labeled PK 11195 binding to peripheral-type benzodiazepine recognition sites correlated with their potencies to stimulate steroid production. Similar findings were observed in bovine and rat adrenocortical cell preparations. These results suggest that ligands of the peripheral-type benzodiazepine recognition site acting on this mitochondrial receptor can enhance steroid production. This action may contribute specificity to the pharmacological profile of drugs preferentially acting on the benzodiazepine recognition site associated with the outer membrane of certain mitochondrial populations.

  12. Pet imaging of peripheral benzodiazepine binding sites in brain tumors

    International Nuclear Information System (INIS)

    Junck, L.; Jewett, D.M.; Olsen, J.M.; Kilbourn, M.R.; Koeppe, R.A.; Young, A.B.; Greenberg, H.S.; Kuhl, D.E.

    1991-01-01

    Studies in vitro have shown that the peripheral-type benzodiazepine binding site (PBBS) is present in moderate to high density on malignant gliomas as well as in areas of reactive gliosis, but in low density in normal brain. PK 11195 is an isoquinoline derivative that binds selectively to the PBBS but not to the central benzodiazepine receptor. We have used [ 11 C]PK 11195 with positron emission tomography (PET) to study brain tumors and cerebral infarcts. Preliminary results showed that, in 13 of 18 patients with astrocytomas, [ 11 C]PK 11195 radioactivity was increased in tumor compared to remote brain and that the concentration ratios of tumor-to-remote brain were higher for high grade astrocytomas than for low grade astrocytomas. Pharmacokinetic analysis suggests that the increased activity in tumor probably does not result from alterations in blood flow or vascular permeability. Patients with lymphoma, meningioma, medulloblastoma, brain metastasis, and neurosarcoidosis have also shown increased radioactivity in tumor. Among eight patients with acute and subacute cerebral infarcts, activity in the infarct was increased in seven and was often greatest at the periphery. We conclude that [ 11 C]PK 11195 is a promising radiopharmaceutical for further investigation of brain tumors as well as diseases characterized by reactive gliosis

  13. Visualization of specific binding sites of benzodiazepine in human brain

    International Nuclear Information System (INIS)

    Shinotoh, H.; Yamasaki, T.; Inoue, O.; Itoh, T.; Suzuki, K.; Hashimoto, K.; Tateno, Y.; Ikehira, H.

    1986-01-01

    Using 11C-labeled Ro15-1788 and positron emission tomography, studies of benzodiazepine binding sites in the human brain were performed on four normal volunteers. Rapid and high accumulation of 11C activity was observed in the brain after i.v. injection of [11C]Ro15-1788, the maximum of which was within 12 min. Initial distribution of 11C activity in the brain was similar to the distribution of the normal cerebral blood flow. Ten minutes after injection, however, a high uptake of 11C activity was observed in the cerebral cortex and moderate uptake was seen in the cerebellar cortex, the basal ganglia, and the thalamus. The accumulation of 11C activity was low in the brain stem. This distribution of 11C activity was approximately parallel to the known distribution of benzodiazepine receptors. Saturation experiments were performed on four volunteers with oral administration of 0.3-1.8 mg/kg of cold Ro15-1788 prior to injection. Initial distribution of 11C activity following injection peaked within 2 min and then the accumulation of 11C activity decreased rapidly and remarkably throughout the brain. The results indicated that [11C] Ro15-1788 associates and dissociates to specific and nonspecific binding sites rapidly and has a high ratio of specific receptor binding to nonspecific binding in vivo. Carbon-11 Ro15-1788 is a suitable radioligand for the study of benzodiazepine receptors in vivo in humans

  14. Application of gamma-aminobutyric acid type A-benzodiazepine receptor imaging for study of neuropsychiatric disorders

    International Nuclear Information System (INIS)

    Bao Weiqi; Qiu Chun; Guan Yihui

    2012-01-01

    Gamma-aminobutyric acid type A-benzodiazepine receptors are heterogeneous polypeptide pentamers widely spread in the central nervous system on the neuron membrane. Different subunit combinations educe various neuro-inhibitory pharmacological effects such as sedative, hypnosis, anticonvulsion and anxiolysis. PET can be utilized to study the binding of the receptors in vivo. PET radioligands of gamma-aminobutyric acid type A-benzodiazepine receptors can be classified into 3 types: antagonists,agonists and reverse agonists, of which antagonist radiotracer 11 C-flumazenil is the most commonly applied in epilepsy, anxiety disorders, depression, vegetative state,addiction and other neuro-psychiatric disorders. (authors)

  15. Regional specific binding of [11C]RO 15 1788 to central type benzodiazepine receptors in human brain: quantitative evaluation by PET

    International Nuclear Information System (INIS)

    Pappata, S.; Samson, Y.; Chavoix, C.; Prenant, C.; Maziere, M.; Baron, J.C.

    1988-01-01

    The central type benzodiazepine receptors were studied in 17 healthy human subjects with 11 C-RO 15 1788 and positron emission tomography (PET). The brain regional distribution of the tracer in eight control studies performed after injection of trace doses of 11 C-RO 15 1788 was consistent with that of benzodiazepine receptors. Saturation studies with co-injected cold RO 15 1788 in the remaining subjects showed a dose-dependent decrease of brain radiotracer until full inhibition of specific binding was achieved with doses above 0.1 mg/kg (four studies). Based on the results, a simple method to estimate the specifically bound 11 C-RO 15 1788 regionally in a single PET study is proposed, using the data from the full-saturation studies as a stable estimate of the nondisplaceable radioligand concentration. Using this method, it was found that quasiequilibrium between the estimated specifically bound and nondisplaceable components was achieved at times equal to or longer than 20 min after tracer administration. The validity of this method was partly supported by further results, showing a good agreement between the regional specific binding so calculated and postmortem data of receptor density

  16. Imaging of a glioma using peripheral benzodiazepine receptor ligands

    Energy Technology Data Exchange (ETDEWEB)

    Starosta-Rubinstein, S.; Ciliax, B.J.; Penney, J.B.; McKeever, P.; Young, A.B.

    1987-02-01

    Two types of benzodiazepine receptors have been demonstrated in mammalian tissues, one which is localized on neuronal elements in brain and the other, on glial cells and in peripheral tissues such as kidney. In vivo administration of /sup 3/H-labeled PK 11195 (1-(2-chlorophenyl-N-methyl-N-(1-methylpropyl)-3-isoquinoline carboxamide) or (/sup 3/H)flunitrazepam with 5 mg of clonazepam per kg to rats with intracranial C6 gliomas resulted in high levels of tritiated-drug binding to the tumor as shown by quantitative autoradiography. Pharmacological studies indicated that the bound drugs labeled the peripheral benzodiazepine binding site. Binding to the peripheral benzodiazepine site was confirmed primarily to malignant cells with little binding to adjacent normal brain tissue or to necrotic tissue. Tumor cell binding was completely inhibited by preadministration of the peripheral benzodiazepine blocking agent PK 11195 at 5 mg/kg. The centrally selective benzodiazepine ligand clonazepam had no effect on PK 11195 binding to the tumor cells. When binding to other tumor cell lines grown in nude mice and nude athymic rats was evaluated, little or no peripheral benzodiazepine binding was detected on human pheochromocytoma (RN1) and neuroblastoma (SK-N-MC, SK-N-SH) tumor cells, respectively. However, high densities of peripheral benzodiazepine binding sites were observed on tumors derived from a human glioma cell line (ATCC HTB 14, U-87 MG). The presence of high concentrations of specific peripheral benzodiazepine receptors on glial tumors suggests that human primary central nervous system tumors could be imaged and diagnosed using peripheral benzodiazepine ligands labeled with positron- or gamma-emitting isotopes.

  17. Benzodiazepines: rat pinealocyte binding sites and augmentation of norepinephrine-stimulated N-acetyltransferase activity

    Energy Technology Data Exchange (ETDEWEB)

    Matthew, E.; Parfitt, A.G.; Sugden, D.; Engelhardt, D.L.; Zimmerman, E.A.; Klein, D.C.

    1984-02-01

    Studies of (/sup 3/H)diazepam binding to intact rat pineal cells were carried out in tissue culture preparations. The binding was saturable, reversible and proportional to the number of cells used. Scatchard analysis resulted in a linear plot (Kd . 23 nM, maximum binding sites (Bmax) . 1.56 pmol/mg of protein for cells in monolayer culture; Kd . 7 nM, Bmax . 1.3 pmol/mg of protein for cells in suspension culture). Inhibition constants (Ki) for clonazepam (500 nM), flunitrazepam (38 nM) and Ro-5-4864 (5 nM) indicated that the binding sites were probably of the ''peripheral'' type. In addition, the effects of diazepam on norepinephrine-stimulated N-acetyltransferase (NAT) activity were studied in organ culture and dissociated cell culture. Diazepam (10-50 microM) both prolonged and increased the magnitude of the norepinephrine-induced increase in NAT activity but did not affect the initial rate of rise of enzyme activity. The effect was dose-dependent and was also seen with clonazepam, flunitrazepam and Ro-5-4864, but not with Ro-15-1788. Diazepam, by itself, at these concentrations, had no effect on NAT, but enzyme activity was increased by higher concentrations (0.1-1 mM). Although a relationship between the (/sup 3/H)diazepam binding sites described here and the effect of benzodiazepines on NAT cannot be established from these studies, the data suggest that the benzodiazepines may alter melatonin levels through their action on NAT.

  18. Limited tryptic proteolysis of the benzodiazepine binding proteins in different species reveals structural homologies.

    Science.gov (United States)

    Friedl, W; Lentes, K U; Schmitz, E; Propping, P; Hebebrand, J

    1988-12-01

    Peptide mapping can be used to elucidate further the structural similarities of the benzodiazepine binding proteins in different vertebrate species. Crude synaptic membrane preparations were photoaffinity-labeled with [3H]flunitrazepam and subsequently degraded with various concentrations of trypsin. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by fluorography allowed a comparison of the molecular weights of photolabeled peptides in different species. Tryptic degradation led to a common peptide of 40K in all species investigated, a finding indicating that the benzodiazepine binding proteins are structurally homologous in higher bony fishes and tetrapods.

  19. Selective pharmacological modulation of renal peripheral-type benzodiazepine binding by treatment with diuretic drugs

    International Nuclear Information System (INIS)

    Lukeman, D.S.; Vaughn, D.A.; Fanestil, D.D.

    1988-01-01

    The authors have assessed the effects of in vivo administration of different classes of diuretic drugs on the expression of the peripheral-type benzodiazepine binding site (PBBS) in crude membranes derived from the cortex and outer medulla of rat kidney by saturation analysis with the PBBS-selective ligands [ 3 H]RO5-4864 and [ 3 H]PH 11195 in cortex and [ 3 H]RO5-4864 in outer medulla. Administration for 14-15 days of furosemide, a drug that blocks NaCl-KCl coupled transport in the thick ascending limb of the loop of Henle, produced a significant doubling in the PBBS density (B/sub max/) in outer medulla, a region of the kidney rich in thick ascending limbs, and produced a lesser but significant increase in PBBS density in the cortex. Conversely, administration for 14-15 days of the carbonic anhydrase inhibitor acetazolamide, which acts predominantly in the proximal tubule, and hydrochlorothiazide, which acts predominantly in the early distal tubule, elicited statistically significant increases in PBBS density in renal cortex but not in renal outer medulla. Furthermore, all drug treatments were without effect on the equilibrium dissociation constants (K/sub d/s) of [ 3 H]RO5-4864 and [ 3 H]PK 11195 binding to cortical and outer medullary membrane preparations. These findings demonstrate that the PBBS can be selectively up-regulated in different regions of the kidney by diuretic drugs with different modes/sites of action. 50 references, 1 table

  20. Interactions of pyrethroid insecticides with GABAA and peripheral-type benzodiazepine receptors

    International Nuclear Information System (INIS)

    Devaud, L.L.

    1988-01-01

    Pyrethroid insecticides are potent proconvulsants in the rat. All pyrethroids evincing proconvulsant activity elicited a similar 25-30% maximal reduction of seizure threshold. The Type II pyrethroids were the most potent proconvulsants with 1RαS, cis cypermethrin having an ED 50 value of 6.3 nmol/kg. The proconvulsant activity of both Type I and Type II pyrenthroids was blocked by pretreatment with PK 11195, the peripheral-type benzodiazepine receptor (PTBR) antagonist. In contrast, phenytoin did not antagonize the proconvulsant activity of either deltamethrin or permethrin. Pyrethroids displaced the specific binding of [ 3 H]Ro5-4864 to rat brain membranes with a significant correlation between the log EC 50 values for their activities as proconvulsants and the log IC 50 values for their inhibition of [ 3 H]Ro5-4864 binding. Both Ro5-4864 and pyrethroid insecticides were found to influence specific [ 35 S]TBPS binding in a GABA-dependent manner. PK 11195 and the Type II pyrethroid, deltamethrin antagonized the Ro5-4864-induced modulation of [ 35 S]TBPS binding. Pyrethroid insecticides, Ro5-4864 and veratridine influenced GABA-gated 36 Chloride influx. Moreover, the Type II pyrethroids elicited an increase in 36 chloride influx in the absence of GABA-stimulation. Both of these actions were antagonized by PK 11195 and tetrodotoxin

  1. Differential effect of detergents on [3H]Ro 5-4864 and [3H]PK 11195 binding to peripheral-type benzodiazepine-binding sites

    International Nuclear Information System (INIS)

    Awad, M.; Gavish, M.

    1988-01-01

    The present study demonstrates a differential effect of various detergent treatments on [ 3 H]Ro 5-4864 and [ 3 H]PK 11195 binding to peripheral benzodiazepine binding sites (PBS). Triton X-100 caused a decrease of about 70% in [ 3 H]Ro 5-4864 binding to membranes from various peripheral tissues of rat, but had only a negligible effect on [ 3 H]PK 11195 binding. A similar effect of Triton X-100 was observed on guinea pig and rabbit kidney membranes. The decrease in [ 3 H]Ro 5-4864 binding after treatment with Triton X-100 was apparently due to a decrease in the density of PBS, since the affinity remained unaltered. The detergents 3-[(3-cholamidopropyl)-dimethylammonio]-1-propane sulfonate (CHAPS), Tween 20, deoxycholic acid, or digitonin (0.0125%) caused only a minor change in [ 3 H]Ro 5-4864 and [ 3 H]PK 11195 binding to rat kidney membranes; but when concentrations were substantially increased (0.1%), all detergents caused a decrease of at least 50% in [ 3 H]Ro 5-4864 binding, while [ 3 H]PK 11195 binding to rat kidney membranes remained unaffected by the first three detergents, with only a minor decrease (15%) after treatment with digitonin

  2. Inhibition of benzodiazepine binding in vitro by amentoflavone, a constituent of various species of Hypericum.

    Science.gov (United States)

    Baureithel, K H; Büter, K B; Engesser, A; Burkard, W; Schaffner, W

    1997-06-01

    Flower extracts of Hypericum perforatum, Hypericum hirsutum, Hypericum patulum and Hypericum olympicum efficiently inhibited binding of [3H]flumazenil to rat brain benzodiazepine binding sites of the GABAA-receptor in vitro with IC50 values of 6.83, 6.97, 13.2 and 6.14 micrograms/ml, respectively. Single constituents of the extracts like hypericin, the flavones quercetin and luteolin, the glycosylated flavonoides rutin, hyperoside and quercitrin and the biflavone 13, II8-biapigenin did not inhibit binding up to concentrations of 1 microM. In contrast, amentoflavone revealed an IC50 = 14.9 +/- 1.9 nM on benzodiazepine binding in vitro. Comparative HPLC analyses of hypericin and amentoflavone in extracts of different Hypericum species revealed a possible correlation between the amentoflavone concentration and the inhibition of flumazenil binding. For hypericin no such correlation was observed. Our experimental data demonstrate that amentoflavone, in contrast to hypericin, presents a very active compound with regard to the inhibition of [3H]-flumazenil binding in vitro and thus might be involved in the antidepressant effects of Hypericum perforatum extracts.

  3. Affinities and densities of high-affinity [3H]muscimol (GABA-A) binding sites and of central benzodiazepine receptors are unchanged in autopsied brain tissue from cirrhotic patients with hepatic encephalopathy

    International Nuclear Information System (INIS)

    Butterworth, R.F.; Lavoie, J.; Giguere, J.F.; Pomier-Layrargues, G.

    1988-01-01

    The integrity of GABA-A receptors and of central benzodiazepine receptors was evaluated in membrane preparations from prefrontal cortex and caudate nuclei obtained at autopsy from nine cirrhotic patients who died in hepatic coma and an equal number of age-matched control subjects. Histopathological studies revealed Alzheimer Type II astrocytosis in all cases in the cirrhotic group; controls were free from neurological, psychiatric or hepatic diseases. Binding to GABA-A receptors was studied using [ 3 H]muscimol as radioligand. The integrity of central benzodiazepine receptors was evaluated using [ 3 H]flunitrazepam and [ 3 H]Ro15-1788. Data from saturation binding assays was analyzed by Scatchard plot. No modifications of either affinities (Kd) or densities (Bmax) of [ 3 H]muscimol of central benzodiazepine binding sites were observed. These findings do not support recent suggestions that alterations of either high-affinity GABA or benzodiazepine receptors play a significant role in the pathogenesis of hepatic encephalopathy

  4. (/sup 3/H)Clonazepam, like (/sup 3/H)flunitrazepam, is a photoaffinity label for the central type of benzodiazepine receptors

    Energy Technology Data Exchange (ETDEWEB)

    Sieghart, W. (Vienna Univ. (Austria)); Moehler, H. (Hoffmann-La Roche (F.) and Co., Basel (Switzerland))

    1982-06-16

    (/sup 3/H)Clonazepam, like (/sup 3/H)flunitrazepam, is irreversibly bound to membrane proteins of brain tissue when exposed to UV light. In polyacrylamide gel electrophoresis followed by fluorography, the same pattern of photolabelled proteins was obtained in cerebellum and in hippocampus when either (/sup 3/H)clonazepam or (/sup 3/H)flunitrazepam was used as photoaffinity label. Since (/sup 3/H)clonazepam does not interact with the peripheral type of benzodiazepine binding site present in the brain, these results confirm previous evidence that the proteins photolabelled with (/sup 3/H)flunitrazepam are associated with the central type of benzodiazepine receptor.

  5. The interaction of substituted benzamides with brain benzodiazepine binding sites in vitro.

    OpenAIRE

    Horton, R. W.; Lowther, S.; Chivers, J.; Jenner, P.; Marsden, C. D.; Testa, B.

    1988-01-01

    1. The interaction of substituted benzamides with brain benzodiazepine (BDZ) binding sites was examined by their ability to displace [3H]-flunitrazepam ([3H]-FNM) from specific binding sites in bovine cortical membranes in vitro. 2. Clebopride, Delagrange 2674, Delagrange 2335 and BRL 20627 displayed concentration-dependent displacement of [3H]-FNM with IC50 values of 73 nM, 132 nM, 7.7 microM and 5.9 microM, respectively. Other substituted benzamides including metoclopramide, sulpiride, tiap...

  6. Early ontogeny of the central benzodiazepine receptor in human embryos and fetuses

    Energy Technology Data Exchange (ETDEWEB)

    Hebebrand, J.; Hofmann, D.; Reichelt, R.; Schnarr, S.; Knapp, M.; Propping, P.; Foedisch, H.J.

    1988-01-01

    The early ontogeny of the central benzodiazepine receptor (BZR) was investigated in human embryos and fetuses between 7 and 26 weeks of gestation. Brain tissue was gained from terminated pregnancies or spontaneous abortions. Binding studies, which were performed with /sup 3/H-flunitrazepam (FNZ), revealed that specific benzodiazepine binding is already detectable at an embryonal age of 7 weeks post conception. Binding at this early stage can be displaced potently by clonazepam and the inverse agonist ..beta..-CCE. Additionally, /sup 3/H-FNZ binding is enhanced by GABA. Thus, benzodiazepine binding is of the central type. Receptor density increases steeply in whole brain between weeks 8 and 11 of gestation. In frontal cortex receptor density increases gradually between weeks 12 and 26 of gestation. No specific fetal disease entity (including trisomy 21) was consistently associated with exceptionally high or low B/sub max/-values.

  7. Repeated swim stress alters brain benzodiazepine receptors measured in vivo

    International Nuclear Information System (INIS)

    Weizman, R.; Weizman, A.; Kook, K.A.; Vocci, F.; Deutsch, S.I.; Paul, S.M.

    1989-01-01

    The effects of repeated swim stress on brain benzodiazepine receptors were examined in the mouse using both an in vivo and in vitro binding method. Specific in vivo binding of [ 3 H]Ro15-1788 to benzodiazepine receptors was decreased in the hippocampus, cerebral cortex, hypothalamus, midbrain and striatum after repeated swim stress (7 consecutive days of daily swim stress) when compared to nonstressed mice. In vivo benzodiazepine receptor binding was unaltered after repeated swim stress in the cerebellum and pons medulla. The stress-induced reduction in in vivo benzodiazepine receptor binding did not appear to be due to altered cerebral blood flow or to an alteration in benzodiazepine metabolism or biodistribution because there was no difference in [14C]iodoantipyrine distribution or whole brain concentrations of clonazepam after repeated swim stress. Saturation binding experiments revealed a change in both apparent maximal binding capacity and affinity after repeated swim stress. Moreover, a reduction in clonazepam's anticonvulsant potency was also observed after repeated swim stress [an increase in the ED50 dose for protection against pentylenetetrazol-induced seizures], although there was no difference in pentylenetetrazol-induced seizure threshold between the two groups. In contrast to the results obtained in vivo, no change in benzodiazepine receptor binding kinetics was observed using the in vitro binding method. These data suggest that environmental stress can alter the binding parameters of the benzodiazepine receptor and that the in vivo and in vitro binding methods can yield substantially different results

  8. Repeated swim stress alters brain benzodiazepine receptors measured in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Weizman, R.; Weizman, A.; Kook, K.A.; Vocci, F.; Deutsch, S.I.; Paul, S.M.

    1989-06-01

    The effects of repeated swim stress on brain benzodiazepine receptors were examined in the mouse using both an in vivo and in vitro binding method. Specific in vivo binding of (/sup 3/H)Ro15-1788 to benzodiazepine receptors was decreased in the hippocampus, cerebral cortex, hypothalamus, midbrain and striatum after repeated swim stress (7 consecutive days of daily swim stress) when compared to nonstressed mice. In vivo benzodiazepine receptor binding was unaltered after repeated swim stress in the cerebellum and pons medulla. The stress-induced reduction in in vivo benzodiazepine receptor binding did not appear to be due to altered cerebral blood flow or to an alteration in benzodiazepine metabolism or biodistribution because there was no difference in (14C)iodoantipyrine distribution or whole brain concentrations of clonazepam after repeated swim stress. Saturation binding experiments revealed a change in both apparent maximal binding capacity and affinity after repeated swim stress. Moreover, a reduction in clonazepam's anticonvulsant potency was also observed after repeated swim stress (an increase in the ED50 dose for protection against pentylenetetrazol-induced seizures), although there was no difference in pentylenetetrazol-induced seizure threshold between the two groups. In contrast to the results obtained in vivo, no change in benzodiazepine receptor binding kinetics was observed using the in vitro binding method. These data suggest that environmental stress can alter the binding parameters of the benzodiazepine receptor and that the in vivo and in vitro binding methods can yield substantially different results.

  9. Unsaturated free fatty acids increase benzodiazepine receptor agonist binding depending on the subunit composition of the GABAA receptor complex.

    Science.gov (United States)

    Witt, M R; Westh-Hansen, S E; Rasmussen, P B; Hastrup, S; Nielsen, M

    1996-11-01

    It has been shown previously that unsaturated free fatty acids (FFAs) strongly enhance the binding of agonist benzodiazepine receptor ligands and GABAA receptor ligands in the CNS in vitro. To investigate the selectivity of this effect, recombinant human GABAA/benzodiazepine receptor complexes formed by different subunit compositions (alpha x beta y gamma 2, x = 1, 2, 3, and 5; y = 1, 2, and 3) were expressed using the baculovirus-transfected Sf9 insect cell system. At 10(-4) M, unsaturated FFAs, particularly arachidonic (20:4) and docosahexaenoic (22:6) acids, strongly stimulated (> 200% of control values) the binding of [3H]flunitrazepam ([3H]FNM) to the alpha 3 beta 2 gamma 2 receptor combination in whole cell preparations. No effect or small increases in levels of unsaturated FFAs on [3H]FNM binding to alpha 1 beta x gamma 2 and alpha 2 beta x gamma 2 receptor combinations were observed, and weak effects (130% of control values) were detected using the alpha 5 beta 2 gamma 2 receptor combination. The saturated FFAs, stearic and palmitic acids, were without effect on [3H]FNM binding to any combination of receptor complexes. The hydroxylated unsaturated FFAs, ricinoleic and ricinelaidic acids, were shown to decrease the binding of [3H]FNM only if an alpha 1 beta 2 gamma 2 receptor combination was used. Given the heterogeneity of the GABAA/ benzodiazepine receptor subunit distribution in the CNS, the effects of FFAs on the benzodiazepine receptor can be assumed to vary at both cellular and regional levels.

  10. Zolpidem displays heterogeneity in its binding to the nonhuman primate benzodiazepine receptor in vivo.

    Science.gov (United States)

    Schmid, L; Bottlaender, M; Fuseau, C; Fournier, D; Brouillet, E; Mazière, M

    1995-10-01

    The distinctive pharmacological activity of zolpidem in rats compared with classical benzodiazepines has been related to its differential affinity for benzodiazepine receptor (BZR) subtypes. By contrast, in nonhuman primates the pharmacological activity of zolpidem was found to be quite similar to that of classical BZR agonists. In an attempt to explain this discrepancy, we examined the ability of zolpidem to differentiate BZR subtypes in vivo in primate brain using positron emission tomography. The BZRs were specifically labeled with [11C]flumazenil. Radiotracer displacement by zolpidem was monophasic in cerebellum and neocortex, with in vivo Hill coefficients close to 1. Conversely, displacement of [11C]flumazenil was biphasic in hippocampus, amygdala, septum, insula, striatum, and pons, with Hill coefficients significantly smaller than 1, suggesting two different binding sites for zolpidem. In these cerebral regions, the half-maximal inhibitory doses for the high-affinity binding site were similar to those found in cerebellum and neocortex and approximately 100-fold higher for the low-affinity binding site. The low-affinity binding site accounted for zolpidem binding characteristics contrast with those reported for rodents, where three different binding sites were found. Species differences in binding characteristics may explain why zolpidem has a distinctive pharmacological activity in rodents, whereas its pharmacological activity in primates is quite similar to that of classical BZR agonists, except for the absence of severe effects on memory functions, which may be due to the lack of substantial zolpidem affinity for a distinct BZR subtype in cerebral structures belonging to the limbic system.

  11. Benzodiazepine effect of 125I-iomazenil-benzodiazepine receptor binding and serum corticosterone level in a rat model

    International Nuclear Information System (INIS)

    Fukumitsu, Nobuyoshi; Ogi, Shigeyuki; Uchiyama, Mayuki; Mori, Yutaka

    2005-01-01

    To test the change in free or unoccupied benzodiazepine receptor (BZR) density in response to diazepam, we investigated 125 I-iomazenil ( 125 I-IMZ) binding and serum corticosterone levels in a rat model. Wistar male rats, which received psychological stress using a communication box for 5 days, were divided into two groups according to the amount of administered diazepam: no diazepam [D (0)] group and 10 mg/kg per day [D (10)] group of 12 rats each. The standardized uptake value (SUV) of 125 I-IMZ of the D (10) group were significantly lower (P 125 I-IMZ, it is clear that diazepam competed with endogenous ligand for the free BZR sites, and the frontal, parietal and temporal cortices, globus pallidus, hippocampus, amygdala and hypothalamus are important areas in which 125 I-IMZ binding is strongly affected by administration of diazepam

  12. Micromolar-Affinity Benzodiazepine Receptors Regulate Voltage-Sensitive Calcium Channels in Nerve Terminal Preparations

    Science.gov (United States)

    Taft, William C.; Delorenzo, Robert J.

    1984-05-01

    Benzodiazepines in micromolar concentrations significantly inhibit depolarization-sensitive Ca2+ uptake in intact nerve-terminal preparations. Benzodiazepine inhibition of Ca2+ uptake is concentration dependent and stereospecific. Micromolar-affinity benzodiazepine receptors have been identified and characterized in brain membrane and shown to be distinct from nanomolar-affinity benzodiazepine receptors. Evidence is presented that micromolar, and not nanomolar, benzodiazepine binding sites mediate benzodiazepine inhibition of Ca2+ uptake. Irreversible binding to micromolar benzodiazepine binding sites also irreversibly blocked depolarization-dependent Ca2+ uptake in synaptosomes, indicating that these compounds may represent a useful marker for identifying the molecular components of Ca2+ channels in brain. Characterization of benzodiazepine inhibition of Ca2+ uptake demonstrates that these drugs function as Ca2+ channel antagonists, because benzodiazepines effectively blocked voltage-sensitive Ca2+ uptake inhibited by Mn2+, Co2+, verapamil, nitrendipine, and nimodipine. These results indicate that micromolar benzodiazepine binding sites regulate voltage-sensitive Ca2+ channels in brain membrane and suggest that some of the neuronal stabilizing effects of micromolar benzodiazepine receptors may be mediated by the regulation of Ca2+ conductance.

  13. Benzodiazepine receptor antagonists for hepatic encephalopathy

    DEFF Research Database (Denmark)

    Als-Nielsen, B; Gluud, L L; Gluud, C

    2004-01-01

    Hepatic encephalopathy may be associated with accumulation of substances that bind to a receptor-complex in the brain resulting in neural inhibition. Benzodiazepine receptor antagonists may have a beneficial effect on patients with hepatic encephalopathy.......Hepatic encephalopathy may be associated with accumulation of substances that bind to a receptor-complex in the brain resulting in neural inhibition. Benzodiazepine receptor antagonists may have a beneficial effect on patients with hepatic encephalopathy....

  14. 125I-iomazenil - benzodiazepine receptor binding and serum corticosterone level during psychological stress in a rat model

    International Nuclear Information System (INIS)

    Fukumitsu, Nobuyoshi; Ogi, Shigeyuki; Uchiyama, Mayuki; Mori, Yutaka

    2004-01-01

    To test the hypothesis that benzodiazepine receptor density decreases in response to stress, we correlated 125 I-iomazenil ( 125 I-IMZ) binding with serum corticosterone levels in a rat model. Wistar male rats were divided into four groups; control group (CON, 10 rats), no physical or psychological stress; and one-, three-, and five-day stress groups of 12 rats each (1-DAY, 3-DAY, and 5-DAY, respectively), receiving psychological stress for the given number of days. Psychological stress were given to rats with a communication box. The standardized uptake value (SUV) of 125 I-iomazenil of the 3-DAY and 5-DAY showed that 125 I-iomazenil - benzodiazepine receptor binding was significantly reduced in the cortices, accumbens nuclei, amygdala and caudate putamen (p 125 I-IMZ is a useful radioligand to reflect received stress and its binding in the cortices, accumbens nuclei, amygdala and caudate putamen is strongly affected by psychological stress

  15. Biochemical study of multiple drug recognition sites on central benzodiazepine receptors

    Energy Technology Data Exchange (ETDEWEB)

    Trifiletti, R.R.

    1986-01-01

    The benzodiazepine receptor complex of mammalian brain possesses recognition sites which mediate (at least in part) the pharmacologic actions of the 1,4-benzodiazepines and barbiturates. Evidence is provided suggesting the existence of least seven distinct drug recognition sites on this complex. Interactions between the various recognition sites have been explored using radioligand binding techniques. This information is utilized to provide a comprehensive scheme for characterizing receptor-active drugs on an anxiolytic-anticonvulsant/proconvulsant continuum using radioligand binding techniques, as well as a comprehensive program for identifying potential endogenous receptor-active substances. Further evidence is provided here supporting the notion of benzodiazepine recognition site heterogeneity. Classical 1,4-benzodiazepines do not appear to differentiate two populations of benzodiazepine receptors in an equilibrium sense, but appear to do so in a kinetic sense. An apparent physical separation of the two receptor subtypes can be achieved by differential solubilization. The benzodiazepine binding subunit can be identified by photoaffinity labeling with the benzodiazepine agonist (/sup 3/H)flunitrazepan. Conditions for reproducible partial proteolytic mapping of (/sup 3/H)flunitrazepam photoaffinity labeled receptors are established. From these maps, it is concluded that there are probably no major differences in the primary sequence of the benzodiazepine binding subunit in various regions of the rat central nervous system.

  16. 125I-iomazenil-benzodiazepine receptor binding during psychological stress in rats

    International Nuclear Information System (INIS)

    Fukumitsu, Nobuyoshi; Tsuchida, Daisuke; Ogi, Shigeyuki; Uchiyama, Mayuki; Mori, Yutaka

    2002-01-01

    We investigated the changes in 125 I-iomazenil ( 125 I-IMZ) benzodiazepine receptor (BZR) binding with psychological stress in a rat model. Six male Wistar rats were placed under psychological stress for 1 hour by using a communication box. No physical stress was not received. 1.85 MBq of 125 I-IMZ was injected into the lateral tail vein and the rat was killed 3 hours later. Twenty-micormeter-thick sections of the brain were collected and % injected dose per body weight (% ID/BW) of eleven regions (frontal, parietal, temporal, occipital cortices, caudate putamen, accumubens nuclei, globus pallidus, amygdala, thalamus, hippocampus and hypothalamus) were calculated by autoradiography. The %ID/BW of rats which were placed under psychological stress was compared with that of 6 control rats. The %ID/BW of rats which were placed under psychological stress diffusely tended to show a reduction in 125 I-IMZ-BZR binding. A significant decrease in BZR binding was observed in the hippocampus of the rats which were placed under psychological stress. 125 I-IMZ-BZR binding tended to decrease throughout the brain. (author)

  17. Identification, characterization, and purification of a 65,000 dalton protein in rat brain is photolabeled by nitro-containing benzodiazepines

    Energy Technology Data Exchange (ETDEWEB)

    Bowling, A.C.

    1988-01-01

    Benzodiazepines bind to two well-characterized classes of nanomolar-affinity binding sites, the central and the peripheral types. Although these sites appear to mediate many of the effects of these compounds, they cannot account for all of the biochemical and physiologic effects of the benzodiazepines. In this investigation, a protein that is photolabeled by NO{sub 2}-containing benzodiazepines was identified and characterized in rat brain by performing photaffinity labeling experiments with ({sup 3}H)-clonazepam and ({sup 3}H)-flunitrazepam. These experiments demonstrate that this photolabeled protein has a molecular weight of 65,000 daltons. Photolabeling of the protein was saturable, inhibited in a stereoselective manner by benzodiazepine enantiomers, inhibited by therapeutically-relevant concentrations of many different NO{sub 2}-containing benzodiazepines, and was not inhibited by more than 70 non-benzodiazepine compounds. The photolabeled protein is distinct from the central and peripheral sites on the basis of molecular weight, benzodiazepine inhibitory potencies, subcellular localization, and tissue distribution.

  18. Physiology and physiopathology of central type Benzodiazepine receptors: Study in the monkey and in human brain using positron emission tomography

    International Nuclear Information System (INIS)

    Hantraye, P.

    1987-01-01

    A new non-invasive technique that allows to study in a living subject central type benzodiazepine receptors is developed. A combined approach is applied using a specific positron-emitting radiotracer for the in vivo labelling of the receptors and positron emission tomography allowing, by external detection, a quantitative determination of tissue radioactivity. The radioligand used for the in vivo labelling of benzodiazepine receptors is the antagonist RO 15-1788 labelled with carbon 11. The various stages of the study are described: in vivo characterization in the monkey of central type benzodiazepine receptors; characterization of central type benzodiazepine receptors in human brain using selective molecules for the BZ1 benzodiazepine subclass; demonstration of the heterogeneity of central type benzodiazepine receptors in the brain; study of pathological alteration of benzodiazepine receptors in experimental epilepsy [fr

  19. Benzodiazepines have high-affinity binding sites and induce melanogenesis in B16/C3 melanoma cells.

    OpenAIRE

    Matthew, E; Laskin, J D; Zimmerman, E A; Weinstein, I B; Hsu, K C; Engelhardt, D L

    1981-01-01

    We found that two markers of differentiation, tyrosinase (monophenol, dihydroxyphenylalanine:oxygen oxidoreductase, EC 1.14.18.1) activity and melanin synthesis, are induced by diazepam in B16/C3 mouse melanoma cells. We also demonstrated high-affinity binding sites for [3H]diazepam in these cells by radioreceptor assay, and we visualized binding to the cell surface by fluorescence microscopy with a benzodiazepine analog conjugated to a fluorescein-labeled protein. Our studies also showed tha...

  20. Functional modulation of cerebral gamma-aminobutyric acidA receptor/benzodiazepine receptor/chloride ion channel complex with ethyl beta-carboline-3-carboxylate: Presence of independent binding site for ethyl beta-carboline-3-carboxylate

    Energy Technology Data Exchange (ETDEWEB)

    Taguchi, J.; Kuriyama, K. (Kyoto Prefectural Univ. of Medicine (Japan))

    1990-05-01

    Effect of ethyl beta-carboline-3-carboxylate (beta-CCE) on the function of gamma-aminobutyric acid (GABA)A receptor/benzodiazepine receptor/chloride ion channel complex was studied. Beta-CCE noncompetitively and competitively inhibited (3H)flunitrazepam binding to benzodiazepine receptor, but not (3H)muscimol binding to GABAA receptor as well as t-(3H)butylbicycloorthobenzoate (( 3H) TBOB) binding to chloride ion channel, in particulate fraction of the mouse brain. Ro15-1788 also inhibited competitively (3H) flunitrazepam binding. On the other hand, the binding of beta-(3H)CCE was inhibited noncompetitively and competitively by clonazepam and competitively by Ro15-1788. In agreement with these results, benzodiazepines-stimulated (3H)muscimol binding was antagonized by beta-CCE and Ro15-1788. Gel column chromatography for the solubilized fraction from cerebral particulate fraction by 0.2% sodium deoxycholate (DOC-Na) in the presence of 1 M KCl indicated that beta-(3H)CCE binding site was eluted in the same fraction (molecular weight, 250,000) as the binding sites for (3H)flunitrazepam, (3H)muscimol and (3H)TBOB. GABA-stimulated 36Cl- influx into membrane vesicles prepared from the bovine cerebral cortex was stimulated and attenuated by flunitrazepam and beta-CCE, respectively. These effects of flunitrazepam and beta-CCE on the GABA-stimulated 36Cl- influx were antagonized by Ro15-1788. The present results suggest that the binding site for beta-CCE, which resides on GABAA receptor/benzodiazepine receptor/chloride ion channel complex, may be different from that for benzodiazepine. Possible roles of beta-CCE binding site in the allosteric inhibitions on benzodiazepine binding site as well as on the functional coupling between chloride ion channel and GABAA receptor are also suggested.

  1. Peripheral-type benzodiazepine receptor: a protein of mitochondrial outer membranes utilizing porphyrins as endogenous ligands

    International Nuclear Information System (INIS)

    Snyder, S.H.; Verma, A.; Trifiletti, R.R.

    1987-01-01

    The peripheral-type benzodiazepine receptor is a site identified by its nanomolar affinity for [ 3 H]diazepam, similar to the affinity of diazepam for the central-type benzodiazepine receptor in the brain. The peripheral type benzodiazepine receptor occurs in many peripheral tissues but has discrete localizations as indicated by autoradiographic studies showing uniquely high densities of the receptors in the adrenal cortex and in Leydig cells of the testes. Subcellular localization studies reveal a selective association of the receptors with the outer membrane of mitochondria. Photoaffinity labeling of the mitochondrial receptor with [ 3 H]flunitrazepam reveals two discrete labeled protein bands of 30 and 35 kDa, respectively. The 35-kDa band appears to be identical with the voltage-dependent anion channel protein porin. Fractionation of numerous peripheral tissues reveals a single principal endogenous ligand for the receptor, consisting of porphyrins, which display nanomolar affinity. Interactions of porphyrins with the mitochondrial receptor may clarify its physiological role and account for many pharmacological actions of benzodiazepines

  2. Food deprivation modulates gamma-aminobutyric acid receptors and peripheral benzodiazepine binding sites in rats.

    Science.gov (United States)

    Weizman, A; Bidder, M; Fares, F; Gavish, M

    1990-12-03

    The effect of 5 days of food deprivation followed by 5 days of refeeding on gamma-aminobutyric acid (GABA) receptors, central benzodiazepine receptors (CBR), and peripheral benzodiazepine binding sites (PBzS) was studied in female Sprague-Dawley rats. Starvation induced a decrease in the density of PBzS in peripheral organs: adrenal (35%; P less than 0.001), kidney (33%; P less than 0.01), and heart (34%; P less than 0.001). Restoration of [3H]PK 11195 binding to normal values was observed in all three organs after 5 days of refeeding. The density of PBzS in the ovary, pituitary, and hypothalamus was not affected by starvation. Food deprivation resulted in a 35% decrease in cerebellar GABA receptors (P less than 0.01), while CBR in the hypothalamus and cerebral cortex remained unaltered. The changes in PBzS observed in the heart and kidney may be related to the long-term metabolic stress associated with starvation and to the functional changes occurring in these organs. The down-regulation of the adrenal PBzS is attributable to the suppressive effect of hypercortisolemia on pituitary ACTH release. The reduction in cerebellar GABA receptors may be an adaptive response to food deprivation stress and may be relevant to the proaggressive effect of hunger.

  3. gamma-Aminobutyric acid- and benzodiazepine-induced modulation of [35S]-t-butylbicyclophosphorothionate binding to cerebellar granule cells

    International Nuclear Information System (INIS)

    Gallo, V.; Wise, B.C.; Vaccarino, F.; Guidotti, A.

    1985-01-01

    t-Butylbicyclophosphorothionate (TBPS) is a bicyclophosphate derivative with potent picrotoxin-like convulsant activity that binds with high affinity and specificity to a Cl- channel-modulatory site of the gamma-aminobutyric acid (GABA)/benzodiazepine receptor complex. Using intact cerebellar granule cells maintained in primary culture, the authors have studied the modifications induced by GABA and diazepam on the ion channel-modulatory binding site labeled by [ 35 S]TBPS. At 25 degrees C, and in a modified Locke solution, the [ 35 S]TBPS specific binding, determined by displacing the radioligand with an excess (10(-4) M) of picrotoxin, was approximately 70% of the total radioactivity bound to the cells. [ 35 S]TBPS specific binding was saturable with a Kd of approximately 100 nM, a Bmax of approximately 440 fmol/mg of protein, and a Hill coefficient of 1.18. Neither cerebellar astrocytes maintained in culture for 2 weeks nor a neuroblastoma cell line (NB-2A) exhibited any specific [ 35 S]TBPS binding. Muscimol (0.3 to 5 microM) enhanced and bicuculline (0.1 to 5 microM) inhibited [ 35 S]TBPS specific binding to intact cerebellar granule cells. The effect of muscimol and bicuculline on [ 35 S]TBPS binding was noncompetitive. Muscimol (0.1 to 5 microM) reversed bicuculline inhibition in a dose-dependent fashion but failed to reverse picrotoxin-induced inhibition. [ 35 S]TBPS binding was also modulated by benzodiazepine receptor ligands. The binding was increased by diazepam and decreased by 6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylic acid methylester. Muscimol (0.05 microM) failed to reverse bicuculline inhibition in the absence of diazepam, but it became effective in the presence of 0.1 to 1 microM diazepam

  4. {sup 125}I-iomazenil-benzodiazepine receptor binding during psychological stress in rats

    Energy Technology Data Exchange (ETDEWEB)

    Fukumitsu, Nobuyoshi; Tsuchida, Daisuke; Ogi, Shigeyuki; Uchiyama, Mayuki; Mori, Yutaka [Jikei Univ., Tokyo (Japan). School of Medicine

    2002-05-01

    We investigated the changes in {sup 125}I-iomazenil ({sup 125}I-IMZ) benzodiazepine receptor (BZR) binding with psychological stress in a rat model. Six male Wistar rats were placed under psychological stress for 1 hour by using a communication box. No physical stress was not received. 1.85 MBq of {sup 125}I-IMZ was injected into the lateral tail vein and the rat was killed 3 hours later. Twenty-micormeter-thick sections of the brain were collected and % injected dose per body weight (% ID/BW) of eleven regions (frontal, parietal, temporal, occipital cortices, caudate putamen, accumubens nuclei, globus pallidus, amygdala, thalamus, hippocampus and hypothalamus) were calculated by autoradiography. The %ID/BW of rats which were placed under psychological stress was compared with that of 6 control rats. The %ID/BW of rats which were placed under psychological stress diffusely tended to show a reduction in {sup 125}I-IMZ-BZR binding. A significant decrease in BZR binding was observed in the hippocampus of the rats which were placed under psychological stress. {sup 125}I-IMZ-BZR binding tended to decrease throughout the brain. (author)

  5. {sup 125}I-iomazenil - benzodiazepine receptor binding and serum corticosterone level during psychological stress in a rat model

    Energy Technology Data Exchange (ETDEWEB)

    Fukumitsu, Nobuyoshi E-mail: GZL13162@nifty.ne.jp; Ogi, Shigeyuki; Uchiyama, Mayuki; Mori, Yutaka

    2004-02-01

    To test the hypothesis that benzodiazepine receptor density decreases in response to stress, we correlated {sup 125}I-iomazenil ({sup 125}I-IMZ) binding with serum corticosterone levels in a rat model. Wistar male rats were divided into four groups; control group (CON, 10 rats), no physical or psychological stress; and one-, three-, and five-day stress groups of 12 rats each (1-DAY, 3-DAY, and 5-DAY, respectively), receiving psychological stress for the given number of days. Psychological stress were given to rats with a communication box. The standardized uptake value (SUV) of {sup 125}I-iomazenil of the 3-DAY and 5-DAY showed that {sup 125}I-iomazenil - benzodiazepine receptor binding was significantly reduced in the cortices, accumbens nuclei, amygdala and caudate putamen (p<0.05). Serum corticosterone level ratio appeared to be slightly elevated in 3-DAY and 5-DAY, although this elevation was not significant. These data suggest that {sup 125}I-IMZ is a useful radioligand to reflect received stress and its binding in the cortices, accumbens nuclei, amygdala and caudate putamen is strongly affected by psychological stress.

  6. Preservation of peripheral benzodiazepine receptors: differential effects of freezing on [3H]Ro 5-4864 and [3H]PK 11195 binding

    International Nuclear Information System (INIS)

    Basile, A.S.; Ostrowski, N.L.; Skolnick, P.

    1987-01-01

    A statistically significant decrease in the density of peripheral benzodiazepine receptors was observed in renal membranes of rats beginning 2 weeks after adrenalectomy when compared with sham-operated controls. This decrease in peripheral benzodiazepine receptor density was manifest as a decrease in the Bmax of two ligands [ 3 H]Ro 5-4864 and [ 3 H]PK 11195, without accompanying changes in their apparent affinity (Kd) for this site. Similar changes were not seen in another aldosterone-sensitive organ, the submandibular salivary gland. The decrease in peripheral benzodiazepine receptor density in observed in adrenalectomized rat renal membranes was restored to control levels after 1 week of aldosterone administration using a dose (12.5 micrograms/kg/day) that had no effect on peripheral benzodiazepine receptor density in sham-operated animals. In contrast, dexamethasone administration (50 micrograms/kg/day, 1 week) had no effect on renal peripheral benzodiazepine receptor density when administered to either adrenalectomized or sham-operated rats. Further, adrenal demedullation had no effect on renal peripheral benzodiazepine receptor density or affinity. The decrease in peripheral benzodiazepine receptor density was localized to the renal cortex and the outer stripe of the medulla by gross dissection of renal slices and renal tissue section autoradiography. The specific effect of adrenalectomy on renal peripheral benzodiazepine receptor density, the lack of direct effect of aldosterone on [ 3 H]Ro 5-4864 binding, and the localization of the change in peripheral benzodiazepine receptor density to the renal cortex and outer stripe suggests that these changes may reflect an adaptation of the renal nephron (possibly the distal convoluted tubule, intermediate tubule and/or the collecting duct) to the loss of mineralocorticoid hormones

  7. A Unified Model of the GABA(A) Receptor Comprising Agonist and Benzodiazepine Binding Sites

    DEFF Research Database (Denmark)

    Kongsbak, Kristine Grønning; Bergmann, Rikke; Sørensen, Pernille Louise

    2013-01-01

    We present a full-length a1b2c2 GABA receptor model optimized for agonists and benzodiazepine (BZD) allosteric modulators. We propose binding hypotheses for the agonists GABA, muscimol and THIP and for the allosteric modulator diazepam (DZP). The receptor model is primarily based on the glutamate......-gated chloride channel (GluCl) from C. elegans and includes additional structural information from the prokaryotic ligand-gated ion channel ELIC in a few regions. Available mutational data of the binding sites are well explained by the model and the proposed ligand binding poses. We suggest a GABA binding mode...... of the agonists in the orthosteric site. The carbonyl group of DZP is predicted to interact with two threonines a1T206 and c2T142, similar to the acidic moiety of GABA. The chlorine atom of DZP is placed near the important a1H101 and the N-methyl group near a1Y159, a1T206, and a1Y209. We present a binding mode...

  8. Benzodiazepine effect of {sup 125}I-iomazenil-benzodiazepine receptor binding and serum corticosterone level in a rat model

    Energy Technology Data Exchange (ETDEWEB)

    Fukumitsu, Nobuyoshi [Proton Medical Research Center, University of Tsukuba, Ibaragi, 305-8575 (Japan)]. E-mail: gzl13162@nifty.ne.jp; Ogi, Shigeyuki [Department of Radiology, Jikei University School of Medicine, Tokyo, 105-8461 (Japan); Uchiyama, Mayuki [Department of Radiology, Jikei University School of Medicine, Tokyo, 105-8461 (Japan); Mori, Yutaka [Department of Radiology, Jikei University School of Medicine, Tokyo, 105-8461 (Japan)

    2005-01-01

    To test the change in free or unoccupied benzodiazepine receptor (BZR) density in response to diazepam, we investigated {sup 125}I-iomazenil ({sup 125}I-IMZ) binding and serum corticosterone levels in a rat model. Wistar male rats, which received psychological stress using a communication box for 5 days, were divided into two groups according to the amount of administered diazepam: no diazepam [D (0)] group and 10 mg/kg per day [D (10)] group of 12 rats each. The standardized uptake value (SUV) of {sup 125}I-IMZ of the D (10) group were significantly lower (P<.05) than those of the D (0) group in the frontal, parietal and temporal cortices, globus pallidus, hippocampus, amygdala and hypothalamus. The serum corticosterone level ratio in the D (10) group was significantly lower than that in the D (0) group (P<.05). From the change in serum corticosterone levels, diazepam attenuated the psychological stress produced by the physical stress to animals in adjacent compartments. From the reduced binding of {sup 125}I-IMZ, it is clear that diazepam competed with endogenous ligand for the free BZR sites, and the frontal, parietal and temporal cortices, globus pallidus, hippocampus, amygdala and hypothalamus are important areas in which {sup 125}I-IMZ binding is strongly affected by administration of diazepam.

  9. Mitochondrial benzodiazepine receptors regulate steroid biosynthesis.

    OpenAIRE

    Mukhin, A G; Papadopoulos, V; Costa, E; Krueger, K E

    1989-01-01

    Recent observations on the steroid synthetic capability within the brain open the possibility that benzodiazepines may influence steroid synthesis in nervous tissue through interactions with peripheral-type benzodiazepine recognition sites, which are highly expressed in steroidogenic cells and associated with the outer mitochondrial membrane. To examine this possibility nine molecules that exhibit a greater than 10,000-fold difference in their affinities for peripheral-type benzodiazepine bin...

  10. Benzodiazepine receptor and neurotransmitter studies in the brain of suicides

    Energy Technology Data Exchange (ETDEWEB)

    Manchon, M.; Kopp, N.; Rouzioux, J.J.; Lecestre, D.; Deluermoz, S.; Miachon, S.

    1987-12-14

    The characteristics of benzodiazepine binding sites were studied on frozen sections of hippocampus of 7 suicides and 5 controls subjects, using biochemical and autoradiographic techniques. /sup 3/H flunitrazepam was used as ligand, clonazepam and CL 218,872 as displacing agents. Some neurotransmitters or their derivatives were evaluated quantitatively in parallel in the hippocampal tissue by liquid chromatography. The authors observed mainly an increase in the Ki of CL 218,872 subtype I binding sites in suicides, and an increase in % of type I binding sites. Among neurotransmitters, only norepinephrine differed significantly between controls and suicides. 36 references, 3 figures, 1 table.

  11. Benzodiazepine receptor and neurotransmitter studies in the brain of suicides

    International Nuclear Information System (INIS)

    Manchon, M.; Kopp, N.; Rouzioux, J.J.; Lecestre, D.; Deluermoz, S.; Miachon, S.

    1987-01-01

    The characteristics of benzodiazepine binding sites were studied on frozen sections of hippocampus of 7 suicides and 5 controls subjects, using biochemical and autoradiographic techniques. 3 H flunitrazepam was used as ligand, clonazepam and CL 218,872 as displacing agents. Some neurotransmitters or their derivatives were evaluated quantitatively in parallel in the hippocampal tissue by liquid chromatography. The authors observed mainly an increase in the Ki of CL 218,872 subtype I binding sites in suicides, and an increase in % of type I binding sites. Among neurotransmitters, only norepinephrine differed significantly between controls and suicides. 36 references, 3 figures, 1 table

  12. GABA/benzodiazepine receptor complex in long-sleep and short-sleep mice

    International Nuclear Information System (INIS)

    Marley, R.J.

    1987-01-01

    LS mice are more sensitive to benzodiazepine-induced anesthesia; however, the two lines do not differ in their hypothermic response to flurazepam. SS mice are more resistant to 3-mercaptopropionic acid-induced seizures and more sensitive to the anticonvulsant effects of benzodiazepines. The various correlates of GABA and benzodiazepine actions probably are the results of different mechanisms of action and/or differential regional control. Bicuculline competition for 3 H-GABA binding sites is greater in SS cerebellar tissue and 3 H-flunitrazepam binding is greater in the mid-brain region of LS mice. GABA enhancement of 3 H-flunitrazepma binding is greater in SS mice. Ethanol also enhances 3 H-flunitrazepam binding and increases the levels of 3 H-flunitrazepam binding above those observed for GABA. Using correlational techniques on data from LS and SS mice and several inbred mouse strains, it was demonstrated that a positive relationship exists between the degree of receptor coupling within the GABA receptor complex and the degree of resistance to seizures

  13. Size-exclusion chromatographic reconstitution of the bovine brain benzodiazepine receptor : Effects of lipid environment on the binding characteristics

    NARCIS (Netherlands)

    Viel, G.T; Yang, Q; Lundahl, P; Ensing, K; de Zeeuw, R.A

    1997-01-01

    The benzodiazepine receptor from calf brain was solubilized with sodium deoxycholate (2 mg/ml) in the presence of 0.5 M KCl and protease inhibitors, and bound flunitrazepam with an equilibrium dissociation constant (K-d) of 2.7+/-1.2 nM and with 0.40+/-0.04 pmol binding sites per mg protein (B-max).

  14. Characterization of astrocytic and neuronal benzodiazepine receptors

    Energy Technology Data Exchange (ETDEWEB)

    Bender, A.S.

    1988-01-01

    Primary cultures of astrocytes and neurons express benzodiazepine receptors. Neuronal benzodiazepine receptors were of high-affinity, K{sub D} values were 7.5-43 nM and the densities of receptors (B{sub max}) were 924-4131 fmol/mg protein. Astrocytes posses a high-affinity benzodiazepine receptor, K{sub D} values were 6.6-13 nM. The B{sub max} values were 6,033-12,000 fmol/mg protein. The pharmacological profile of the neuronal benzodiazepine receptor was that of the central-type benzodiazepine receptor, where clonazepam has a high-affinity and Ro 5-4864 (4{prime}-chlorodiazepam) has a low-affinity. Whereas astrocytic benzoidazepine receptor was characteristic of the so called peripheral-type benzodiazepine receptors, which shows a high-affinity towards Ro 5-4863, and a low-affinity towards clonazepam. The astrocytic benzodiazepine receptors was functionally correlated with voltage dependent calcium channels, since dihydropyridines and benzodiazepines interacted with ({sup 3}H) diazepam and ({sup 3}H) nitrendipine receptors with the same rank order of potency, showing a statistically significant correlation. No such correlation was observed in neurons.

  15. Decrease in benzodiazepine receptor binding in a patient with Angelman syndrome detected by iodine-123 iomazenil and single-photon emission tomography

    International Nuclear Information System (INIS)

    Odano, Ikuo; Anezaki, Toshiharu; Ohkubo, Masaki; Yonekura, Yoshiharu; Onishi, Yoshihiro; Inuzuka, Takashi; Takahashi, Makoto; Tsuji, Shoji

    1996-01-01

    A receptor mapping technique using iodine-123 iomazenil and single-photon emission tomography (SPET) was employed to examine benzodiazepine receptor binding in a patient with Angelman syndrome (AS). AS is characterized by developmental delay, seizures, inappropriate laughter and ataxic movement. In this entity there is a cytogenic deletion of the proximal long arm of chromosome 15q11-q13, where the gene encoding the GABA A receptor β3 subunit (GABRB3) is located. Since the benzodiazepine receptor is constructed as a receptor-ionophore complex that contains the GABA A receptor, it is a suitable marker for GABA-ergic synapsis. To determine whether benzodiazepine receptor density, which indirectly indicates changes in GABA A receptor density, is altered in the brain in patients with AS, we investigated a 27-year-old woman with AS using 123 I-iomazenil and SPET. Receptor density was quantitatively assessed by measuring the binding potential using a simplified method. Regional cerebral blood flow was also measured with N-isopropyl-p- 123 iodoamphetamine. We demonstrated that benzodiazepiine receptor density is severely decreased in the cerebellum, and mildly decreased in the frontal and temporal cortices and basal ganglia, a result which is considered to indicate decreased GABA A receptor density in these regions. Although the deletion of GABRB3 was not observed in the present study, we indirectly demonstrated the disturbance of inhibitory neurotransmission mediated by the GABA A receptor in the investigated patient. 123 I-iomazenil with SPET was useful to map benzodiazepine receptors, which indicate GABA A receptor distribution and their density. (orig.)

  16. The interaction of substituted benzamides with brain benzodiazepine binding sites in vitro.

    Science.gov (United States)

    Horton, R W; Lowther, S; Chivers, J; Jenner, P; Marsden, C D; Testa, B

    1988-08-01

    1. The interaction of substituted benzamides with brain benzodiazepine (BDZ) binding sites was examined by their ability to displace [3H]-flunitrazepam ([3H]-FNM) from specific binding sites in bovine cortical membranes in vitro. 2. Clebopride, Delagrange 2674, Delagrange 2335 and BRL 20627 displayed concentration-dependent displacement of [3H]-FNM with IC50 values of 73 nM, 132 nM, 7.7 microM and 5.9 microM, respectively. Other substituted benzamides including metoclopramide, sulpiride, tiapride, sultopride and cisapride were inactive at 10(-5) M. 3. Inhibition by clebopride and Delagrange 2674 of [3H]-FNM binding was apparently competitive and readily reversible. 4. In the presence of gamma-aminobutyric acid (GABA), the ability of diazepam and Delagrange 2674 to displace [3H]-Ro 15-1788 binding was increased 3.6 and 1.6 fold respectively, compared to the absence of GABA, while ethyl beta-carboline-3-carboxylate (beta CCE) and clebopride were less potent in the presence of GABA. 5. Diazepam was 30 fold less potent at displacing [3H]-Ro 15-1788 in membranes that had been photoaffinity labelled with FNM than in control membranes, whereas the potency of beta CCE did not differ. Clebopride and Delagrange 2674 showed a less than two fold loss of potency in photoaffinity labelled membranes. 6. The pattern of binding of clebopride and Delagrange 2674 in these in vitro tests is similar to that found previously with partial agonists or antagonists at BDZ binding sites. 7. Clebopride and Delagrange 2674 inhibited [3H]-FNM binding with similar potency in rat cerebellar and hippocampal membranes, suggesting they have no selectivity for BDZ1 and BDZ2 binding sites. 8. Clebopride and Delagrange 2674 are structurally dissimilar to other BDZ ligands and represent another chemical structure to probe brain BDZ binding sites.

  17. GABA and benzodiazepine receptors in the gerbil brain after transient ischemia: demonstration by quantitative receptor autoradiography

    International Nuclear Information System (INIS)

    Onodera, H.; Sato, G.; Kogure, K.

    1987-01-01

    Quantitative receptor autoradiography was used to measure the binding of gamma-aminobutyric acid (GABA) and benzodiazepine receptors after ischemia by means of transient occlusion of bilateral common carotid arteries in the gerbil. [ 3 H]Muscimol was used to label the GABAA receptors and [ 3 H]flunitrazepam to label central type benzodiazepine receptors. In the superolateral convexities of the frontal cortices, [ 3 H]muscimol binding was increased in 60% of the animals killed 3 days after ischemia, and decreased in 67% of the animals killed 27 days after ischemia. Twenty-seven days after ischemia, [ 3 H]flunitrazepam binding in the substantia nigra pars reticulata increased to 252% of the control, though the increase in [ 3 H]muscimol binding was not significant. In the dorsolateral region of the caudate putamen, marked neuronal necrosis and depletion of both [ 3 H]muscimol and [ 3 H]flunitrazepam binding sites were observed 27 days after ischemia, the ventromedial region being left intact. In spite of the depletion of pyramidal cells in the CA1 region of the hippocampus, both [ 3 H]muscimol and [ 3 H]flunitrazepam binding sites were preserved 27 days after ischemia. Since our previous study revealed that adenosine A1 binding sites were depleted in the CA1 subfield of the hippocampus after ischemia correlating with neuronal damage, GABAA and benzodiazepine receptors may not be distributed predominantly on the pyramidal cells in the CA1 region

  18. Quantitative autoradiography of muscarinic and benzodiazepine receptors in the forebrain of the turtle, Pseudemys scripta

    International Nuclear Information System (INIS)

    Schlegel, J.R.; Kriegstein, A.R.

    1987-01-01

    The distribution of muscarinic and benzodiazepine receptors was investigated in the turtle forebrain by the technique of in vitro receptor autoradiography. Muscarinic binding sites were labeled with 1 nM 3 H-quinuclidinyl benzilate ( 3 H-QNB), and benzodiazepine sites were demonstrated with the aid of 1 nM 3 H-flunitrazepam ( 3 H-FLU). Autoradiograms generated on 3 H-Ultrofilm apposed to tissue slices revealed regionally specific distributions of muscarinic and benzodiazepine binding sites that are comparable with those for mammalian brain. Dense benzodiazepine binding was found in the anterior olfactory nucleus, the lateral and dorsal cortices, and the dorsal ventricular ridge (DVR), a structure with no clear mammalian homologue. Muscarinic binding sites were most dense in the striatum, accumbens, DVR, lateral geniculate, and the anterior olfactory nucleus. Cortical binding sites were studied in greater detail by quantitative analysis of autoradiograms generated by using emulsion-coated coverslips. Laminar gradients of binding were observed that were specific for each radioligand; 3 H-QNB sites were most dense in the inner molecular layer in all cortical regions, whereas 3 H-FLU binding was generally most concentrated in the outer molecular layer and was least dense through all layers in the dorsomedial cortex. Because pyramidal cells are arranged in register in turtle cortex, the laminar patterns of receptor binding may reflect different receptor density gradients along pyramidal cell dendrites

  19. Peripheral benzodiazepine receptors are decreased during cocaine withdrawal in humans.

    Science.gov (United States)

    Javaid, J I; Notorangelo, M P; Pandey, S C; Reddy, P L; Pandey, G N; Davis, J M

    1994-07-01

    In the present study, homovanillic acid in plasma (pHVA) and benzodiazepine receptors (3H-PK11195 binding) in neutrophil membranes were determined in blood obtained from cocaine-dependent (DSM-III-R) adult male inpatients at baseline-(within 72 hr of last cocaine use) and after 3 weeks of cocaine abstinence, and normal controls. The mean (+/- SEM) pHVA at baseline (10.3 ng/ml +/- 1.1) was similar to normals and did not change after 3 weeks of cocaine abstinence. Similarly, the binding indices of benzodiazepine receptors in cocaine-dependent subjects as a group were not significantly different than in normal controls. In 10 cocaine-dependent subjects, however, where both blood samples were available, the number of 3H-PK11195 binding sites was significantly (p < 0.05) decreased after 3 weeks of cocaine abstinence (mean +/- sem: Bmax = 6371 +/- 657 fmol/mg protein) compared with baseline (Bmax = 7553 +/- 925 fmol/mg protein), although there were no differences in the binding affinity (mean +/- sem: KD = 8.6 +/- 1.2 nmol/L after 3 weeks of abstinence compared with 8.1 +/- 1.0 nmol/L at baseline). These preliminary results suggest that peripheral benzodiazepine receptors may play an important role in the pathophysiology of cocaine withdrawal in cocaine-dependent human subjects.

  20. Analysis of subcomponents of the gamma-aminobutyric acid/benzodiazepine receptor macromolecular complex in mammalian central nervous system

    International Nuclear Information System (INIS)

    McCabe, R.T.

    1987-01-01

    Since the presence of endogenous gamma-aminobutyric acid (GABA) may affect benzodiazepine binding to tissue sections in autoradiographic studies, a protocol designed to check for this influence has been investigated. [ 3 H]Flunitrazepam (1 nM) was used to label benzodiazepine receptors for autoradiographic localization. Bicuculline was added to the incubation medium of an additional set of tissue sections to antagonize any potential effect of endogenous GABA. Binding in these sections was compared to that occurring in another set in which excess GABA was added to create further GABA enhancement. Binding was also compared to adjacent sections which were treated similarly but also preincubated in distilled-deionized water to burst the cells by osmotic shock and eliminate endogenous GABA, thereby preventing any effect on benzodiazepine binding. The results indicated that endogenous GABA is indeed present in the slide-mounted tissue sections and is affecting benzodiazepine receptor binding differentially in various regions of the brain depending on the density of GABAergic innervation. Scatchard analysis of saturation data demonstrated that the alteration in BZ binding due to GABA was a result of a change in the affinity rather than number of receptors present

  1. Evidence for involvement of the astrocytic benzodiazepine receptor in the mechanism of action of convulsant and anticonvulsant drugs

    International Nuclear Information System (INIS)

    Bender, A.S.; Hertz, L.

    1988-01-01

    The anticonvulsant drugs carbamazepine, phenobarbital, trimethadione, valproic acid and ethosuximide at pharmacologically relevant concentrations inhibit [ 3 H]diazepam binding to astrocytes in primary cultures but have much less effect on a corresponding preparation of neurons. Phenytoin as well as pentobarbital (which is not used chronically as an anticonvulsant) are equipotent in the two cell types. The convulsants picrotoxinin and pentylenetetrazol, the convulsant benzodiazepine RO 5-3663 and the two convulsant barbiturates DMBB and CHEB similarly inhibit diazepam binding to astrocytes but have little effect on neurons. On the basis of these findings it is suggested that these convulsants and anticonvulsants owe at least part of their effect to an interaction with the astrocytic benzodiazepine receptor, perhaps by interference with a calcium channel

  2. Nootropic nefiracetam inhibits proconvulsant action of peripheral-type benzodiazepines in epileptic mutant EL mice.

    Science.gov (United States)

    Nakamoto, Yurie; Shiotani, Tadashi; Watabe, Shigeo; Nabeshima, Toshitaka; Yoshii, Mitsunobu

    2004-10-01

    Piracetam and structurally related nootropics are known to potentiate the anticonvulsant effects of antiepileptic drugs. It remains to be seen, however, whether these nootropics inhibit proconvulsant actions of many toxic agents including Ro 5-4864, a specific agonist for peripheral-type benzodiazepine receptors (PBR). The present study was designed to address this issue using EL mice, an animal model of epilepsy. In behavioral pharmacological experiments, EL mice were highly susceptible to convulsions induced by Ro 5-4864 (i.p.) in comparison with nonepileptic DDY mice. Nefiracetam administered orally to EL mice inhibited spontaneous seizures. In DDY mice, convulsions induced by Ro 5-4864 were prevented by nefiracetam when administered by i.v. injection. Aniracetam (i.v.) was partially effective, but piracetam and oxiracetam were ineffective as anticonvulsants. Binding assay for brain tissues revealed a higher density of mitochondrial PBR in EL mice compared with DDY mice. Binding of the PBR ligands Ro 5-4864 to either EL or DDY mouse brain was inhibited by micromolar concentrations of these nootropic agents in the sequence of nefiracetam > aniracetam > oxiracetam, piracetam. This rank order is identical to potency as anticonvulsants. These data suggest that nefiracetam may prevent toxic effects of PBR agonists through interacting with PBR.

  3. Benzodiazepine antagonism by harmane and other beta-carbolines in vitro and in vivo.

    Science.gov (United States)

    Rommelspacher, H; Nanz, C; Borbe, H O; Fehske, K J; Müller, W E; Wollert, U

    1981-03-26

    Harmane and other related beta-carbolines are putative endogenous ligands of the benzodiazepine receptor. Since the compounds are potent convulsants they may have agonist activities at the benzodiazepine receptor while the benzodiazepines may be antagonists. This hypothesis was proved by comparing the in vivo and in vitro antagonism of benzodiazepines by harmane and other beta-carbolines. Harmane is clearly a competitive inhibitor of benzodiazepine receptor binding in vitro. Moreover, harmane-induced convulsions can be inhibited reversibly by diazepam in a manner which is consistent with the assumption of competitive antagonism in vivo. For some beta-carboline derivatives a correlation was found between the affinity for the benzodiazepine receptor in vitro and the convulsive potency in vivo. Thus, the data reported suggest that harmane or other related beta-carbolines are putative endogenous agonists of the benzodiazepine receptor. This suggestion is further supported by the observation that diazepam is equally potent in inhibiting harmane- or picrotoxin-induced convulsions, indicating a convulsive mechanism within the GABA receptor-benzodiazepine receptor system.

  4. Imaging benzodiazepine receptors in man with C-11-suriclone and positron emission tomography

    International Nuclear Information System (INIS)

    Frost, J.J.; Dannals, R.F.; Ravert, H.T.; Wilson, A.A.; Links, J.M.; Trifiletti, R.; Snyder, S.H.; Wagner, H.N. Jr.

    1985-01-01

    Suriclone is a potent cyclopyrrolone, anti-anxiety drug which binds to the benzodiazepine receptor complex (BZR) with high affinity. Suriclone binds to a site on the BZR distinct from the site where benzodiazepines bind. The K/sub D/ of suriclone at 37oC is 0.03 nM. C-11-suriclone (SUR) was synthesized by reacting C-CH3I with the appropriate amine precursor. SUR (1 μg/kg) was injected IV into a baboon alone or with 1 mg/kg of Ro-151788, a benzodiazepine antagonist, and serial PET scans of the brain were obtained. High radioactivity concentrations were observed in the cerebral cortex and cerebellum which contain high densities of BZR, intermediate concentrations in thalamus and low concentrations in the striatum. When Ro-151788 was given a uniform distribution of radioactivity was observed; the radioactivity was reduced to ca. 25% of control values in the brain which was contained within the PET slice. SUR (0.2 μg/kg) was next administered to a human subject. From 30-60 minutes after injection high radioactivity concentrations were observed in the cerebral cortex and cerebellum, intermediate concentrations in the thalamus and a low concentration in the caudate. Radioactivity in the cerebral cortex and cerebellum decreased slowly with time, implying that binding of SUR to a high affinity site had occurred. These results demonstrate utility of SUR for measuring binding to the benzodiazepine receptor complex non-invasively in man

  5. Pregnenolone biosynthesis in C6-2B glioma cell mitochondria: regulation by a mitochondrial diazepam binding inhibitor receptor.

    OpenAIRE

    Papadopoulos, V; Guarneri, P; Kreuger, K E; Guidotti, A; Costa, E

    1992-01-01

    The C6-2B glioma cell line, rich in mitochondrial receptors that bind with high affinity to benzodiazepines, imidazopyridines, and isoquinolinecarboxamides (previously called peripheral-type benzodiazepine receptors), was investigated as a model to study the significance of the polypeptide diazepam binding inhibitor (DBI) and the putative DBI processing products on mitochondrial receptor-regulated steroidogenesis. DBI and its naturally occurring fragments have been found to be present in high...

  6. [Suicidal poisoning with benzodiazepines].

    Science.gov (United States)

    Chodorowski, Z; Sein Anand, J

    1997-01-01

    In the period from 1987 to 1996, 103 patients with suicidal benzodiazepines poisoning were treated, including 62 women and 41 men from 16 to 79 (mean 34) years old. 23 persons were poisoned only by benzodiazepines, in 80 remaining cases intoxications were mixed eg. including benzodiazepines and alcohol, tricyclic antidepressants, barbiturates, opioids, phenothiazines. The main causes of suicides were mainly depression, drug addiction and alcoholism. Nobody died in the benzodiazepines group, while mortality rate in the group of mixed poisoning was 4%. Prescribing benzodiazepines by physicians was quite often not justified and facilitated, among others, accumulation of the dose sufficient for suicide attempt. Flumazenil was efficient for leading out from coma in 86% of cases with poisoning only by benzodiazepines and 13% of cases with mixed intoxications mainly containing benzodiazepines and alcohol or carbamazepine.

  7. Benzodiazepine receptor antagonists for acute and chronic hepatic encephalopathy

    DEFF Research Database (Denmark)

    Als-Nielsen, B; Kjaergard, L L; Gluud, C

    2001-01-01

    The pathogenesis of hepatic encephalopathy is unknown. It has been suggested that liver failure leads to the accumulation of substances that bind to a receptor-complex in the brain resulting in neural inhibition which may progress to coma. Several trials have assessed benzodiazepine receptor...

  8. PK11195 binding to the peripheral benzodiazepine receptor as a marker of microglia activation in multiple sclerosis and experimental autoimmune encephalomyelitis

    DEFF Research Database (Denmark)

    Vowinckel, E; Reutens, D; Becher, B

    1997-01-01

    Activated glial cells are implicated in regulating and effecting the immune response that occurs within the CNS as part of multiple sclerosis (MS) and its animal model experimental autoimmune encephalomyelitis (EAE). The peripheral benzodiazepine receptor (PBR) is expressed in glial cells. We...... examined the utility of using in vitro and in vivo ligand binding to the PBR as a measure of lesion activity in autoimmune CNS demyelinating diseases. Applying a combined autoradiography and immunohistochemical approach to spinal cord and brain tissues from mice with EAE, we found a correlation at sites...... of inflammatory lesions between [3H]-PK11195 binding and immunoreactivity for the activated microglial/macrophage marker Mac-1/CD11b. In MS tissues, [3H]-PK11195 binding correlated with sites of immunoreactivity for the microglial/macrophage marker CD68, at the edges of chronic active plaques. Positron emission...

  9. Daily rhythms of benzodiazepine receptor numbers in frontal lobe and cerebellum of the rat

    International Nuclear Information System (INIS)

    Brennan, M.J.W.; Volicer, L.; Moore-Ede, M.C.; Borsook, D.

    1985-01-01

    Behavioral, biochemical and neurophysiological evidence suggests that gamma-aminobutyric acid (GABA) may play an important role in the neural control of circadian rhythms. Central receptors for benzodiazepines are functionally coupled to GABA receptors and appear to mediate behavioral effects of exogenous benzodiazepines. The binding of 3 H-flunitrazepam to synaptic plasma membranes prepared from various regions of rat brain was examined at 6-hour intervals over a 36-hour period. Prominent daily rhythms in receptor number (Bmax) were observed in the frontal lobe and the cerebellum but not in the temporoparietal regions, hypothalamus or medulla/pons. Binding was highest during periods of sleep/low activity with a significant decrease occurring just prior to waking. These results suggest that daily fluctuations in benzodiazepine receptor numbers may be related to the temporal control of sleep/wake and muscle activity cycles. 23 references, 1 figure, 1 table

  10. Pharmacological evaluation of an [(123)I] labelled imidazopyridine-3-acetamide for the study of benzodiazepine receptors.

    Science.gov (United States)

    Mattner, Filomena; Mardon, Karine; Loc'h, Christian; Katsifis, Andrew

    2006-06-13

    In vitro binding of the iodinated imidazopyridine, N',N'-dimethyl-6-methyl-(4'-[(123)I]iodophenyl)imidazo[1,2-a]pyridine-3-acetamide [(123)I]IZOL to benzodiazepine binding sites on brain cortex, adrenal and kidney membranes is reported. Saturation experiments showed that [(123)I]IZOL, bound to a single class of binding site (n(H)=0.99) on adrenal and kidney mitochondrial membranes with a moderate affinity (K(d)=30 nM). The density of binding sites was 22+/-6 and 1.2+/-0.4 pmol/mg protein on adrenal and kidney membranes, respectively. No specific binding was observed in mitochondrial-synaptosomal membranes of brain cortex. In biodistribution studies in rats, the highest uptake of [(123)I]IZOL was found 30 min post injection in adrenals (7.5% ID/g), followed by heart, kidney, lung (1% ID/g) and brain (0.12% ID/g), consistent with the distribution of peripheral benzodiazepine binding sites. Pre-administration of unlabelled IZOL and the specific PBBS drugs, PK 11195 and Ro 5-4864 significantly reduced the uptake of [(123)I]IZOL by 30% (p<0.05) in olfactory bulbs and by 51-86% (p<0.01) in kidney, lungs, heart and adrenals, while it increased by 30% to 50% (p<0.01) in the rest of the brain and the blood. Diazepam, a mixed CBR-PBBS drug, inhibited the uptake in kidney, lungs, heart, adrenals and olfactory bulbs by 32% to 44% (p<0.01) but with no effect on brain uptake and in blood concentration. Flumazenil, a central benzodiazepine drug and haloperidol (dopamine antagonist/sigma receptor drug) displayed no effect in [(123)I]IZOL in peripheral organs and in the brain. [(123)I]IZOL may deserve further development for imaging selectively peripheral benzodiazepine binding sites.

  11. Benzodiazepine poisoning in elderly

    OpenAIRE

    Perković-Vukčević Nataša; Vuković-Ercegović Gordana; Šegrt Zoran; Đorđević Snežana; Jović-Stošić Jasmina

    2016-01-01

    Background/Aim. Benzodiazepines are among the most frequently ingested drugs in self-poisonings. Elderly may be at greater risk compared with younger individuals due to impaired metabolism and increased sensitivity to benzodiazepines. The aim of this study was to assess toxicity of benzodiazepines in elderly attempted suicide. Methods. A retrospective study of consecutive presentations to hospital after self-poisoning with benzodiazepines was done. Collecte...

  12. Benzodiazepine abuse among the elderly

    Directory of Open Access Journals (Sweden)

    Shalini Singh

    2016-01-01

    Full Text Available Benzodiazepines belong to the hypnotic-sedative class of drugs which have anxiolytic, sedative, and hypnotic properties. These drugs have been in clinical use for at least half a century. The propensity for development of dependence, especially on prescription benzodiazepines, coupled with the risk of falls and cognitive impairment due to benzodiazepines makes the elderly population susceptible to adverse outcomes with the use of benzodiazepines, and hence, cautious use is desired in this population. This review discusses the various aspects pertaining to benzodiazepine abuse in the elderly including pharmacology, prevalence of abuse, adverse consequences of benzodiazepine abuse, and subsequently assessment and management of elderly patients with benzodiazepine abuse.

  13. In vivo (/sup 3/H)flunitrazepam binding: imaging of receptor regulation

    Energy Technology Data Exchange (ETDEWEB)

    Ciliax, B.J.; Penney, J.B. Jr.; Young, A.B.

    1986-08-01

    The use of (/sup 3/H)flunitrazepam as a ligand to measure alterations in benzodiazepine receptors in vivo in rats was investigated. Animals were injected with (/sup 3/H)flunitrazepam i.v., arterial samples of (/sup 3/H)flunitrazepam were obtained and, later, the animals were sacrificed to assay brain binding. (/sup 3/H)flunitrazepam enters the brain rapidly and binds to benzodiazepine receptors. About two-thirds of this binding is blocked by predosing the animals with 5 mg/kg of clonazepam. The amount of remaining (nonspecific) binding correlates very well (r = 0.88) with the amount of radioactivity found in plasma at the time of death. A series of rats were lesioned unilaterally with kainic acid in the caudate-putamen several months before the infusion of (/sup 3/H)flunitrazepam. In vivo autoradiography in lesioned rats showed that benzodiazepine binding in globus pallidus and substantia nigra on the side of the lesion was increased significantly as compared to the intact side. The observed changes in benzodiazepine binding were similar to those observed previously in lesioned rats using in vitro techniques. Thus, benzodiazepine receptor regulation can be imaged quantitatively using in vivo binding techniques.

  14. Omega 3 (peripheral type benzodiazepine binding) site distribution in the rat immune system: an autoradiographic study with the photoaffinity ligand [3H]PK 14105

    International Nuclear Information System (INIS)

    Benavides, J.; Dubois, A.; Dennis, T.; Hamel, E.; Scatton, B.

    1989-01-01

    The anatomical distribution of omega 3 (peripheral type benzodiazepine binding) sites in the immune system organs of the rat has been studied autoradiographically at both macroscopic and microscopic levels of resolution using either reversible or irreversible (UV irradiation) labeling with [ 3 H]PK 14105. In thymus sections, [ 3 H]PK 14105 labeled with high affinity (Kd, derived from saturation experiments = 10.8 nM) a single population of sites which possessed the pharmacological characteristics of omega 3 sites. In the thymus gland, higher omega 3 site densities were detected in the cortex than in the medulla; in these subregions, silver grains were associated to small (10-18 microns diameter) cells. In the spleen, omega 3 sites were more abundant in the white than in the red pulp. In the white pulp, silver grains were denser in the marginal zone than in the vicinity of the central artery and labeling was, as in the thymus, associated to small cytoplasm-poor cells. In the red pulp, omega 3 site associated silver grains were observed mainly in the Bilroth cords. In the lymph nodes, the medullary region showed a higher labeling than the surrounding follicles and paracortex. A significant accumulation of silver grains was observed in the lymph node medullary cords. In the intestine, Peyer patches were particularly enriched in omega 3 sites (especially in the periphery of the follicles). The distribution of omega 3 sites in the immune system organs suggests a preferential labeling of cells of T and monocytic lineages. This is consistent with the proposed immunoregulatory properties of some omega 3 site ligands

  15. Soman- or kainic acid-induced convulsions decrease muscarinic receptors but not benzodiazepine receptors

    International Nuclear Information System (INIS)

    Churchill, L.; Pazdernik, T.L.; Cross, R.S.; Nelson, S.R.; Samson, F.E.

    1990-01-01

    [3H]Quinuclidinyl benzilate (QNB) binding to muscarinic receptors decreased in the rat forebrain after convulsions induced by a single dose of either soman, a potent inhibitor of acetylcholinesterase, or kainic acid, an excitotoxin. A Rosenthal plot revealed that the receptors decreased in number rather than affinity. When the soman-induced convulsions were blocked, the decrease in muscarinic receptors at 3 days was less extensive than when convulsions occurred and at 10 days they approached control levels in most of the brain areas. The most prominent decrements in QNB binding were in the piriform cortex where the decline in QNB binding is probably related to the extensive convulsion-associated neuropathology. The decrements in QNB binding after convulsions suggest that the convulsive state leads to a down-regulation of muscarinic receptors in some brain areas. In contrast to the decrease in QNB binding after convulsions, [3H]flunitrazepam binding to benzodiazepine receptors did not change even in the piriform cortex where the loss in muscarinic receptors was most prominent. Thus, it appears that those neuronal processes that bear muscarinic receptors are more vulnerable to convulsion-induced change than those with benzodiazepine receptors

  16. Benzodiazepine poisoning in elderly.

    Science.gov (United States)

    Vukcević, Natasa Perković; Ercegović, Gordana Vuković; Segrt, Zoran; Djordjević, Snezana; Stosić, Jasmina Jović

    2016-03-01

    Benzodiazepines are among the most frequently ingested drugs in self-poisonings. Elderly may be at greater risk compared with younger individuals due to impaired metabolism and increased sensitivity to benzodiazepines. The aim of this study was to assess toxicity of benzodiazepines in elderly attempted suicide. A retrospective study of consecutive presentations to hospital after self-poisoning with benzodiazepines was done. Collected data consisted of patient's characteristics (age, gender), benzodiazepine ingested with its blood concentrations at admission, clinical findings including vital signs and Glasgow coma score, routine blood chemistry, complications of poisoning, details of management, length of hospital stay and outcome. According the age, patients are classified as young (15-40-year old), middle aged (41-65-year old) and elderly (older than 65). During a 2-year observational period 387 patients were admitted because of pure benzodiazepine poisoning. The most frequently ingested drug was bromazepam, the second was diazepam. The incidence of coma was significantly higher, and the length of hospital stay significantly longer in elderly. Respiratory failure and aspiration pneumonia occurred more frequently in old age. Also, flumazenil was more frequently required in the group of elderly patients. Massive benzodiazepines overdose in elderly may be associated with a significant morbidity, including deep coma with aspiration pneumonia, respiratory failure, and even death. Flumazenil is indicated more often to reduce CNS depression and prevent complications of prolonged unconsciousness, but supportive treatment and proper airway management of comatose patients is the mainstay of the treatment of acute benzodiazepine poisoning.

  17. Benzodiazepine receptor antagonists for acute and chronic hepatic encephalopathy

    DEFF Research Database (Denmark)

    Als-Nielsen, B; Kjaergard, L L; Gluud, C

    2001-01-01

    The pathogenesis of hepatic encephalopathy is unknown. It has been suggested that liver failure leads to the accumulation of substances that bind to a receptor-complex in the brain resulting in neural inhibition which may progress to coma. Several trials have assessed benzodiazepine receptor...... antagonists for hepatic encephalopathy, but the results are conflicting....

  18. Different sensitivities to competitive inhibition of benzodiazepine receptor binding of {sup 11}C-iomazenil and {sup 11}C-flumazenil in rhesus monkey brain

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Osamu; Hosoi, Rie; Kobayashi, Kaoru [Osaka Univ., Suita (Japan). Medical School; Itoh, Takashi; Gee, A.; Suzuki, Kazutoshi

    2001-04-01

    The in vivo binding kinetics of {sup 11}C-iomazenil were compared with those of {sup 11}C-flumazenil binding in rhesus monkey brain. The monkey was anesthetized with ketamine and intravenously injected with either {sup 11}C-iomazenil or {sup 11}C-flumazenil in combination with the coadministration of different doses of non-radioactive flumazenil (0, 5 and 20 {mu}g/kg). The regional distribution of {sup 11}C-iomazenil in the brain was similar to that of {sup 11}C-flumazenil, but the sensitivity of {sup 11}C-iomazenil binding to competitive inhibition by non-radioactive flumazenil was much less than that of {sup 11}C-flumazenil binding. A significant reduction in {sup 11}C-flumazenil binding in the cerebral cortex was observed with 20 {mu}g/kg of flumazenil, whereas a relatively smaller inhibition of {sup 11}C-iomazenil binding in the same region was observed with the same dose of flumazenil. These results suggest that {sup 11}C-flumazenil may be a superior radiotracer for estimating benzodiazepine receptor occupancy in the intact brain. (author)

  19. Benzodiazepine poisoning in elderly

    Directory of Open Access Journals (Sweden)

    Perković-Vukčević Nataša

    2016-01-01

    Full Text Available Background/Aim. Benzodiazepines are among the most frequently ingested drugs in self-poisonings. Elderly may be at greater risk compared with younger individuals due to impaired metabolism and increased sensitivity to benzodiazepines. The aim of this study was to assess toxicity of benzodiazepines in elderly attempted suicide. Methods. A retrospective study of consecutive presentations to hospital after self-poisoning with benzodiazepines was done. Collected data consisted of patient's characteristics (age, gender, benzodiazepine ingested with its blood concentrations at admission, clinical findings including vital signs and Glasgow coma score, routine blood chemistry, complications of poisoning, details of management, length of hospital stay and outcome. According the age, patients are classified as young (15-40-year old, middle aged (41-65-year old and elderly (older than 65. Results. During a 2-year observational period 387 patients were admitted because of pure benzodiazepine poisoning. The most frequently ingested drug was bromazepam, the second was diazepam. The incidence of coma was significantly higher, and the length of hospital stay significantly longer in elderly. Respiratory failure and aspiration pneumonia occurred more frequently in old age. Also, flumazenil was more frequently required in the group of elderly patients. Conclusion. Massive benzodiazepines overdose in elderly may be associated with a significant morbidity, including deep coma with aspiration pneumonia, respiratory failure, and even death. Flumazenil is indicated more often to reduce CNS depression and prevent complications of prolonged unconsciousness, but supportive treatment and proper airway management of comatose patients is the mainstay of the treatment of acute benzodiazepine poisoning.

  20. Topology characterization of a benzodiazepine-binding beta-rich domain of the GABAA receptor alpha1 subunit.

    Science.gov (United States)

    Xu, Zhiwen; Fang, Shisong; Shi, Haifeng; Li, Hoiming; Deng, Yiqun; Liao, Yinglei; Wu, Jiun-Ming; Zheng, Hui; Zhu, Huaimin; Chen, Hueih-Min; Tsang, Shui Ying; Xue, Hong

    2005-10-01

    Structural investigation of GABAA receptors has been limited by difficulties imposed by its trans-membrane-complex nature. In the present study, the topology of a membrane-proximal beta-rich (MPB) domain in the C139-L269 segment of the receptor alpha1 subunit was probed by mapping the benzodiazepine (BZ)-binding and epitopic sites, as well as fluorescence resonance energy transfer (FRET) analysis. Ala-scanning and semiconservative substitutions within this segment revealed the contribution of the phenyl rings of Y160 and Y210, the hydroxy group of S186 and the positive charge on R187 to BZ-binding. FRET with the bound BZ ligand indicated the proximity of Y160, S186, R187, and S206 to the BZ-binding site. On the other hand, epitope-mapping using the monoclonal antibodies (mAbs) against the MPB domain established a clustering of T172, R173, E174, Q196, and T197. Based on the lack of FRET between Trp substitutionally placed at R173 or V198 and bound BZ, this epitope-mapped cluster is located on a separate end of the folded protein from the BZ-binding site. Mutations of the five conserved Cys and Trp residues in the MPB domain gave rise to synergistic and rescuing effects on protein secondary structures and unfolding stability that point to a CCWCW-pentad, reminiscent to the CWC-triad "pin" of immunoglobulin (Ig)-like domains, important for the structural maintenance. These findings, together with secondary structure and fold predictions suggest an anti-parallel beta-strand topology with resemblance to Ig-like fold, having the BZ-binding and the epitopic residues being clustered at two different ends of the fold.

  1. Predictors of long-term benzodiazepine abstinence in participants of a randomized controlled benzodiazepine withdrawal program.

    NARCIS (Netherlands)

    Oude Voshaar, R.C.; Gorgels, W.J.M.J.; Mol, A.J.J.; Balkom, A.J.L.M. van; Mulder, J.; Lisdonk, E.H. van de; Breteler, M.H.M.; Zitman, F.G.

    2006-01-01

    OBJECTIVE: To identify predictors of resumed benzodiazepine use after participation in a benzodiazepine discontinuation trial. METHOD: We performed multiple Cox regression analyses to predict the long-term outcome of a 3-condition, randomized, controlled benzodiazepine discontinuation trial in

  2. Predictors of long-term benzodiazepine abstinence in participants of a randomized controlled benzodiazepine withdrawal program

    NARCIS (Netherlands)

    Oude Voshaar, R.C.; Gorgels, W.J.M.J.; Mol, A.J.J.; Balkom, A.J.L.M. van; Mulder, J.; Lisdonk, E.H. van de; Breteler, M.H.M.; Zitman, F.G.

    2006-01-01

    Objective: To identify predictors of resumed benzodiazepine use after participation in a benzodiazepine discontinuation trial. Method: We performed multiple Cox regression analyses to predict the long-term outcome of a 3-condition, randomized, controlled benzodiazepine discontinuation trial in

  3. Methodology for benzodiazepine receptor binding assays at physiological temperature. Rapid change in equilibrium with falling temperature

    International Nuclear Information System (INIS)

    Dawson, R.M.

    1986-01-01

    Benzodiazepine receptors of rat cerebellum were assayed with [ 3 H]-labeled flunitrazepam at 37 0 C, and assays were terminated by filtration in a cold room according to one of three protocols: keeping each sample at 37 degrees C until ready for filtration, taking the batch of samples (30) into the cold room and filtering sequentially in the order 1-30, and taking the batch of 30 samples into the cold room and filtering sequentially in the order 30-1. the results for each protocol were substantially different from each other, indicating that rapid disruption of equilibrium occurred as the samples cooled in the cold room while waiting to be filtered. Positive or negative cooperativity of binding was apparent, and misleading effects of gamma-aminobutyric acid on the affinity of diazepam were observed, unless each sample was kept at 37 0 C until just prior to filtration

  4. Peripheral-type benzodiazepine receptors in bronchoalveolar lavage cells of patients with interstitial lung disease

    International Nuclear Information System (INIS)

    Branley, Howard M.; Bois, Roland M. du; Wells, Athol U.; Jones, Hazel A.

    2007-01-01

    Introduction: PK11195 is a ligand with high affinity for peripheral benzodiazepine receptors (PBRs), which are present in large numbers in macrophages. PBRs play a role in antioxidant pathways and apoptosis, key factors in control of lung health. Intrapulmonary PBRs, assessed in vivo by positron emission tomography (PET), are decreased in interstitial lung disease (ILD) despite increased macrophage numbers. We wished to ascertain whether the observed decrease in in vivo expression of PBRs in the PET scans could be accounted for by a reduction in PBRs per cell by saturation-binding assays of R-PK11195 in cells obtained by bronchoalveolar lavage (BAL). Methods: We performed receptor saturation-binding assays with [ 3 H]-R-PK11195 on a mixed population of cells recovered by BAL to quantify the number of R-PK11195 binding sites per macrophage in 10 subjects with ILD and 10 normal subjects. Results: Receptor affinity [dissociation constant (Kd)] was similar in ILD patients and controls. However, R-PK11195 binding sites per cell [(maximal binding sites available (B max )] were decreased in macrophages obtained by BAL from subjects with ILD compared to normal (P<.0005). Microautoradiography confirmed localization of R-PK11195 to macrophages in a mixed inflammatory cell population obtained by BAL. Conclusion: These results demonstrate that in vitro PBR expression per cell on macrophages obtained by BAL is reduced in patients with ILD indicating a potentially functionally different macrophage phenotype. As PBRs are involved in the orchestration of lung inflammatory responses, this finding offers further insight into the role of macrophages in the pathogenesis of ILDs and offers a potential avenue for pharmacological strategy

  5. Temporal characteristics of stress-induced decrease in benzodiazepine reception in C57BL/6 and BALB/c mice.

    Science.gov (United States)

    Yarkova, M A; Seredenin, S B

    2014-10-01

    We studied the duration of the drop of specific (3)H-flunitrazepam binding by synaptosomal membranes from the brain of C57Bl/6 and BALB/c mice after open-field and "contact with predator" tests. It was found that reduced benzodiazepine reception in BALB/c mice after open-field test persisted for 1.5 h, but no changes of this parameter were found in C57Bl/6 mice. After contact with predator, the binding capacity of the benzodiazepine site of GABAA receptor was reduced for 8 h in BALB/c mice and for 24 h in C57Bl/6 mice.

  6. Autoradiographic localization of benzodiazepine receptors in the rat kidney

    Energy Technology Data Exchange (ETDEWEB)

    Beaumont, K.; Healy, D.P.; Fanestil, D.D.

    1984-11-01

    The localization of benzodiazepine (BZD) receptors in the rat kidney was studied by autoradiography after in vitro labeling of kidney slices with flunitrazepam. The affinity, density, and rank order of displacement of (/sup 3/H)-flunitrazepam by several BZDs (RO 5-4864 > diazepam > clonazepam) demonstrated that binding was to BZD receptors of the peripheral type. In autoradiograms obtained with tritium-sensitive film, a high density of silver grains was obtained in the outer medulla, with lower densities in the cortex. Binding was absent from the inner medulla (papilla). In higher resolution autoradiograms obtained with an emulsion-coated cover slip procedure, silver grains were seen to be concentrated over a tubular element in both outer medulla and cortex, identifiable by morphology and distribution as the thick ascending limb of the loop of Henle and the distal convoluted tubule. The identity of the labeled tubules was confirmed by immunofluorescent localization in adjacent slices of Tamm-Horsfall protein, a specific marker for these segments of tubules. Investigation of the effects of peripherally specific BZDs such as RO 5-4864 on distal tubule function is indicated.

  7. The benzodiazepine/GABA receptor complex during severe ethanol intoxication and withdrawal in the rat

    International Nuclear Information System (INIS)

    Hemmingsen, R.; Braestrup, C.; Nielsen, M.; Barry, D.I.

    1982-01-01

    The benzodiazepine/GABA (gammaaminobutyric acid) receptor complex was investigated during severe ethanol intoxication and withdrawal in the rat. The intragastric intubation technique was used to establish physical ethanol dependence in the animals. Cerebral cortex from male Wistar rats was studied 1) after 31/2 days of severe ethanol intoxication, 2) during the ethanol withdrawal reaction and 3) in a control group. The effect of GABA-ergic activation by muscimol and THIP (4,5,6,7-tetrahydroisoxazole(5,4-c)pyridin-3-01) on 3 H-diazepam binding was unchanged during ethanol intoxication and withdrawal, as was the affinity constant (Ksub(D)) and the maximal number of binding sites (Bsub(max)) for 3 H-flunitrazepam. In conclusion, the benzodiazepine/GABA receptor complex is unlikely to play any causual part in physical ethanol dependence. (author)

  8. Benzodiazepine absetzen im Alter

    DEFF Research Database (Denmark)

    Wolter, Dirk

    2017-01-01

    Although viewed critically in geriatrics, benzodiazepine use is still common among old people. Before reducing the dosage the following questions must be considered: 1. Are there indications for benzodiazepine treatment and will discontinuation cause relevant rebound symptoms of the initial disor...

  9. Benzodiazepines for psychosis-induced aggression or agitation

    DEFF Research Database (Denmark)

    Zaman, Hadar; Sampson, Stephanie J; Beck, Alison Ls

    2017-01-01

    of global state, clearly more people receiving placebo showed no improvement in the medium term (one to 48 hours) (n = 102, 1 RCT, RR 0.62, 95% CI 0.40 to 0.97, very low quality evidence). Benzodiazepines versus antipsychoticsWhen compared with haloperidol, there was no observed effect for benzodiazepines...... improved when receiving benzodiazepines compared with olanzapine (n = 150, 1 RCT, RR 1.84, 95% CI 1.06 to 3.18, very low quality evidence). People receiving benzodiazepines were less likely to experience extrapyramidal effects in the medium term compared to people receiving haloperidol (n = 233, 6 RCTs, RR...... 0.13, 95% CI 0.04 to 0.41, low quality evidence).Benzodiazepines versus combined antipsychotics/antihistaminesWhen benzodiazepine was compared with combined antipsychotics/antihistamines (haloperidol plus promethazine), there was a higher risk of no improvement in people receiving benzodiazepines...

  10. Benzodiazepines

    Science.gov (United States)

    ... injectable preparation and as a syrup (primarily for pediatric patients). Benzodiazepines with a longer duration of ... and clorazepate are also used as anticonvulsants. Methods of abuse Abuse is frequently associated with ...

  11. Increased thermolability of benzodiazepine receptors in cerebral cortex of a baboon with spontaneous seizures: a case report.

    Science.gov (United States)

    Squires, R; Naquet, R; Riche, D; Braestrup, C

    1979-06-01

    The benzodiazepine receptor in the cortex of 1 spontaneously epileptic baboon exhibited an increased rate of thermal inactivation at 65 degrees C when compared with those from 3 other baboons. In other respects (receptor concentration, affinities for flunitrazepam and diazepam, and response to changing pH), the benzodiazepine receptor from this animal was very similar to the receptors in the cortex of 3 other baboons. The 3H-QNB (muscarinic) and 3H-naloxone (opiate) binding sites in the brain of all 4 baboons appeared very similar with respect to all parameters studied (thermal stability, concentration, regional distribution, and affinities for respective ligands). An endogenous factor stabilizing the benzodiazepine receptor could be lacking in the spontaneously epileptic baboon.

  12. Brain concentrations of benzodiazepines are elevated in an animal model of hepatic encephalopathy

    International Nuclear Information System (INIS)

    Basile, A.S.; Pannell, L.; Jaouni, T.; Gammal, S.H.; Fales, H.M.; Jones, E.A.; Skolnick, P.

    1990-01-01

    Brain extracts from rats with hepatic encephalopathy due to thioacetamide-induced fulminant hepatic failure contained 4- to 6-fold higher concentrations of substances that inhibit radioligand binding to benzodiazepine receptors than corresponding control rat extracts. Both isocratic and gradient-elution HPLC indicated that this inhibitory activity was localized in 3-8 peaks with retention times corresponding to deschlorodiazepam, deschlorolorazepam, lorazepam, oxazepam, diazepam, and N-desmethyldiazepam. The presence of diazepam and N-desmethyldiazepam was confirmed by mass spectroscopy. Both mass spectroscopic and radiometric techniques indicated that the concentrations of N-desmethyldiazepam and diazepam in brain extracts from encephalopathic rats were 2-9 and 5-7 times higher, respectively, than in control brain extracts. While benzodiazepines have been identified previously in mammalian and plant tissues, this report demonstrates that concentrations of these substances are increased in a pathophysiological condition. These findings provide a rational basis for the use of benzodiazepine receptor antagonists in the management of hepatic encephalopathy in humans

  13. Isotopically labelled benzodiazepines

    International Nuclear Information System (INIS)

    Liebman, A.A.

    1987-01-01

    This paper reports on the benzodiazepines which are a class of therapeutic agents. Improvements in the analytical methodology in the areas of biochemistry and pharmacology were significant, particularly in the application of chromatographic and spectroscopic techniques. In addition, the discovery and subsequent development of tritium and carbon-14 as an analytical tool in the biological sciences were essentially post-world war II phenomena. Thus, as these new chemical entities were found to be biologically active, they could be prepared in labeled form for metabolic study, biological half-life determination (pharmacokinetics), tissue distribution study, etc. This use of tracer methodology has been liberally applied to the benzodiazepines and also more recently to the study of receptor-ligand interactions, in which tritium, carbon-11 or fluorine-18 isotopes have been used. The history of benzodiazepines as medicinal agents is indeed an interesting one; an integral part of that history is their use in just about every conceivable labeled form

  14. Different effects of long-term haloperidol administration on GABA/sub A/ and benzodiazepine receptors in various parts of the brain

    International Nuclear Information System (INIS)

    Vasar, Oe.Oe.; Nurk, A.M.; Maimets, M.O.; Soosaar, A.H.; Allikmets, L.H.

    1986-01-01

    The data described in this paper are evidence that long-term administration of haloperidol has an opposite effect on the density of GABA/sub A/ and benzodiazepine receptors in the fore- and hindbrain. These changes are reflected at the molecular level as reversal of behavioral effect of the GABA/sub A/ agonist muscimol and the benzodiazepine agonist Ro15-1788. By means of parallel behavioral tests, binding of 3 H-muscimol in the fore- and hindbrain of rats was investigated in experiments in vitro. 3 H-flunitrazepam binding experiments were carried out in vivo on mice. Parallel with reversal of the behavioral effects of muscimol and Ro15-1788, the number of binding sites both for 3 H-muscimol and for 3 H-flunitrazepam in the forebrain was reduced; in the hindbrain the opposite process took place

  15. Benzodiazepine maintenance for alcohol dependence: A case series

    Directory of Open Access Journals (Sweden)

    Shivanand Kattimani

    2017-01-01

    Full Text Available Alcohol addiction is a chronic relapsing syndrome. Benzodiazepines remain as the mainstay for detoxification, taking care of the acute withdrawal syndrome. There is fear of dependence and abuse of benzodiazepines on prolonged use. Here, we selectively interviewed ten cases who were on longer duration of benzodiazepines to elicit their potential perceived benefits, attitudes, and any adverse effect. Three patients experienced adverse effects. None of them had features of benzodiazepine dependence. We opine that in select cases, benzodiazepine use should persist beyond detox period, and its benefits continue beyond the acute withdrawal phase while monitoring their safety/adverse effects.

  16. Modulation of benzodiazepine by lysine and pipecolic acid on pentylenetetrazol-induced seizures

    International Nuclear Information System (INIS)

    Chang, Y.F.; Hargest, V.; Chen, J.S.

    1988-01-01

    L-lysine and its metabolite pipecolic acid (PA) have been studied for their effects on pentylenetetrazol (PTZ)-induced seizures in mice. L-Lysine of L-Pa i.p. significantly increased clonic and tonic latencies in a dose-dependent manner against 90 mg/kg PTZ-induced seizures. L-Lysine but not L-Pa enhanced the anticonvulsant effect of diazepam (DZ). L-Pa i.c.v. showed a slight decrease in clonic latency; it did not enhance the antiseizure activity of DZ; it caused seizures at 0.6 mmol/kg. D-PA i.c.v. displayed an opposite effect compared to its L-isomer. The anticonvulsant effect of L-lysine in terms of increase in seizure latency and survival was even more amplified when tested with a submaximal PTZ concentration. L-Lysine showed an enhancement of specific 3 H-flunitrazepam(FZ) binding to mouse brain membranes both in vitro an din vivo. The possibility of L-lysine acting as a modulator for the GABA/benzodiazepine receptors was demonstrated. Since L-PA showed enhancement of 3 H-FZ binding only in vitro but not in vivo, the anticonvulsant effect of L-PA may not be linked to the GABA/benzodiazepine receptor

  17. Fluorescent-labeled ligands for the benzodiazepine receptor - Part 1 : Synthesis and characterization of fluorescent-labeled benzodiazepines

    NARCIS (Netherlands)

    Janssen, M.J; Hulst, A.J R L; Kellogg, R.M; Hendriks, M.M W B; Ensing, K; de Zeeuw, R.A

    Because radioactive labeled ligands in receptor assays have several disadvantages, we synthesized a number of fluorescent-labeled benzodiazepines. Several fluorophores were attached at different positions of 1,4-benzodiazepine molecules in order to assess the impact of the fluorophores and their

  18. Flumazenil in treatment benzodiazepine withdrawal syndrome: Case report

    Directory of Open Access Journals (Sweden)

    Ramah Aleksandar J.

    2015-01-01

    Full Text Available Background: Today in the world and in Serbia is growing number of people who are addicted to benzodiazepine. A particular problem is the process of detoxification and treatment of benzodiazepine withdrawal syndrome due to a recurrence of symptoms of anxiety disorder, availability of benzodiazepines, falling motivation. Standard procedures have often proved unsuccessful and the last decade, and the search for new protocols, including the flumazenil, benzodiazepine receptor antagonist, is actualized. Case report: The patient aged 48 years was admitted to the specialist psychiatric clinic, for treatment of benzodiazepine addiction. Anxiety disorder was diagnosed since adolescence perennial addiction on benzodiazepines and the initial withdrawal syndrome. Former motivated topical treatments for detoxification were unsuccessful. The presence of dual diagnosis, persistence of both disorders in perennial cycle, treatment resistance and actual motivation contributed to the decision to opt rapid detoxification from benzodiazepines by flumazenil application protocol, for hospital treatment by adjuvant therapy with lamotrigine. After discharge from hospital in stable condition it was with no signs of withdrawal syndrome and a rebound of anxiety symptoms. Lamotrigine medication continued including CBT, held during the one-year abstinence monitoring, with sufficient social functionality. Discussion: The efficacy and safety of flumazenil in the treatment of benzodiazepine withdrawal syndrome was investigated in numerous clinical trials, and the mechanism of action is complex, from the benzodiazepine antagonist to inverse agonist in certain circumstances, as well as 'up-regulation' receptors, which together leads to a reduction in symptoms of abstinence syndrome and anxiety in the longer term after treatment, thereby acting favorably to the adherence and remission. Conclusions: Flumazenil protocol is an efficient method in the treatment of the benzodiazepine

  19. Structural basis for ligand recognition at the benzodiazepine binding site of GABAA alpha 3 receptor, and pharmacophore-based virtual screening approach.

    Science.gov (United States)

    Vijayan, R S K; Ghoshal, Nanda

    2008-10-01

    Given the heterogeneity of GABA(A) receptor, the pharmacological significance of identifying subtype selective modulators is increasingly being recognized. Thus, drugs selective for GABA(A) alpha(3) receptors are expected to display fewer side effects than the drugs presently in clinical use. Hence we carried out 3D QSAR (three-dimensional quantitative structure-activity relationship) studies on a series of novel GABA(A) alpha(3) subtype selective modulators to gain more insight into subtype affinity. To identify the 3D functional attributes required for subtype selectivity, a chemical feature-based pharmacophore, primarily based on selective ligands representing diverse structural classes was generated. The obtained pseudo receptor model of the benzodiazepine binding site revealed a binding mode akin to "Message-Address" concept. Scaffold hopping was carried out across multi-conformational May Bridge database for the identification of novel chemotypes. Further a focused data reduction approach was employed to choose a subset of enriched compounds based on "Drug likeness" and "Similarity-based" methods. These results taken together could provide impetus for rational design and optimization of more selective and high affinity leads with a potential to have decreased adverse effects.

  20. Reduced binding potential of GABA-A/benzodiazepine receptors in individuals at ultra-high risk for psychosis: an [18F]-fluoroflumazenil positron emission tomography study.

    Science.gov (United States)

    Kang, Jee In; Park, Hae-Jeong; Kim, Se Joo; Kim, Kyung Ran; Lee, Su Young; Lee, Eun; An, Suk Kyoon; Kwon, Jun Soo; Lee, Jong Doo

    2014-05-01

    Altered transmission of gamma-aminobutyric acid (GABA), a major inhibitory neurotransmitter, may contribute to the development of schizophrenia. The purpose of the present study was to investigate the presence of GABA-A/benzodiazepine (BZ) receptor binding abnormalities in individuals at ultra-high risk (UHR) for psychosis in comparison with normal controls using [(18)F]-fluoroflumazenil (FFMZ) positron emission tomography (PET). In particular, we set regions of interest in the striatum (caudate, putamen, and nucleus accumbens) and medial temporal area (hippocampus and parahippocampal gyrus). Eleven BZ-naive people at UHR and 15 normal controls underwent PET scanning using [(18)F]-FFMZ to measure GABA-A/BZ receptor binding potential. The regional group differences between UHR individuals and normal controls were analyzed using Statistical Parametric Mapping 8 software. Participants were evaluated using the structured interview for prodromal syndromes and neurocognitive function tasks. People at UHR demonstrated significantly reduced binding potential of GABA-A/BZ receptors in the right caudate. Altered GABAergic transmission and/or the imbalance of inhibitory and excitatory systems in the striatum may be present at the putative prodromal stage and play a pivotal role in the pathophysiology of psychosis.

  1. Alterations of benzodiazepine receptor binding potential in anxiety and somatoform disorders measured by 123I-iomazenil SPECT

    International Nuclear Information System (INIS)

    Tokunaga, Mari; Ida, Ituro; Mikuni, Masahiko; Higuchi, Teruhiko.

    1997-01-01

    123 I-iomazenil (IMZ), a newly developed radioligand which acts on benzodiazepine receptors (BZR) as a partial inverse agonist, made it possible to evaluate the function of central BZR by single photon emission tomography (SPECT). To examine the alterations of the binding potential (BP) in the anxiety state, 123 I-IMZ SPECT was performed in five patients with anxiety and somatoform disorders, and five epileptic patients without anxiety symptoms served as a reference. The BP of BZR was determined by using a table look-up procedure based on a three-compartment, two-parameter model in the bilateral superior frontal, inferior frontal, temporal, parietal, occipital, and cerebellar cortex. The mean BP of patients with anxiety and somatoform disorders was significantly decreased in the superior frontal, temporal, and parietal cortex, in comparison with that of epileptic patients. A significant correlation was observed between the anxiety levels scored on the Hamilton anxiety scale and BP in the right temporal cortex and left superior frontal cortex. These changes in BZR revealed by SPECT suggest the usefulness of 123 I-IMZ SPECT to objectively evaluate anxiety levels in patients with anxiety symptoms. (author)

  2. Application of radioreceptor assay of benzodiazepines for toxicology

    International Nuclear Information System (INIS)

    Aaltonen, L.; Scheinin, M.

    1982-01-01

    A radioreceptor assay (RRA) for determining benzodiazepines (BZ) has been developed and applied to toxicological analysis of serum samples from 21 patients with acute BZ overdosage. The method was sensitive (e.g., lorazepam 17 nM, diazepam 41 nM), and specific for pharmacologically active BZ derivatives. The reproducibility of the results was good (intra-assay variation < 8%, inter-assay variation < 10%). Concentrations measured by the RRA showed a good correlation with those obtained by gas-liquid chromatographic analysis of the same samples. The quantitative results represent the sum of one or several parent substances and all biologically active metabolites, in proportion to their receptor binding affinities. (author)

  3. Pharmacological evaluation of [123I]-CLINDE: a radioiodinated imidazopyridine-3-acetamide for the study of peripheral benzodiazepine binding sites (PBBS).

    Science.gov (United States)

    Mattner, Filomena; Mardon, Karine; Katsifis, Andrew

    2008-04-01

    The study aims to evaluate the iodinated imidazopyridine, N',N'-diethyl-6-Chloro-(4'-[(123)I]iodophenyl)imidazo[1,2-a]pyridine-3-acetamide ([(123)I]-CLINDE) as a tracer for the study of peripheral benzodiazepine binding sites (PBBS). In vitro studies were performed using membrane homogenates and sections from kidney, adrenals, and brain cortex of Sprague-Dawley (SD) rats and incubated with [(123)I]-CLINDE. For in vivo studies, the rats were injected with [(123)I]-CLINDE. In competition studies, PBBS-specific drugs PK11195 and Ro 5-4864 and the CBR specific drug Flumazenil were injected before the radiotracer. In vitro binding studies in adrenal, kidney, and cortex mitochondrial membranes indicated that [(123)I]-CLINDE binds with high affinity to PBBS, K(d) = 12.6, 0.20, and 3.84 nM, respectively. The density of binding sites was 163, 5.3, and 0.34 pmol/mg protein, respectively. In vivo biodistribution indicated high uptake in adrenals (5.4), heart (1.5), lungs (1.5), kidney (1.5) %ID/g at 6 h p.i. In the central nervous system (CNS), the olfactory bulbs displayed the highest uptake; up to six times the activity in blood. Pre-administration of unlabeled CLINDE, PK11195 and Ro 5-4864 (1 mg/kg) reduced the uptake of [(123)I]-CLINDE by 70-55% in olfactory bulbs. In the kidney and heart, a reduction of 60-80% ID/g was observed, while an increase was observed in the adrenals requiring 10 mg/kg for significant displacement. Flumazenil had no effect on uptake in peripheral organs and brain. Metabolite analysis indicated >90% of the radioactivity in the above tissues was intact [(123)I]-CLINDE. [(123)I]-CLINDE displays high and selective uptake for the PBBS and warrants further development as a probe for imaging PBBS using single photon emission computed tomography (SPECT).

  4. Pharmacological evaluation of [123I]-CLINDE: a radioiodinated imidazopyridine-3-acetamide for the study of peripheral benzodiazepine binding sites (PBBS)

    International Nuclear Information System (INIS)

    Mattner, Filomena; Katsifis, Andrew; Mardon, Karine

    2008-01-01

    The study aims to evaluate the iodinated imidazopyridine, N',N'-diethyl-6-Chloro-(4'-[ 123 I]iodophenyl)imidazo [1,2-a]pyridine-3-acetamid e ([ 123 I]-CLINDE) as a tracer for the study of peripheral benzodiazepine binding sites (PBBS). In vitro studies were performed using membrane homogenates and sections from kidney, adrenals, and brain cortex of Sprague-Dawley (SD) rats and incubated with [ 123 I]-CLINDE. For in vivo studies, the rats were injected with [ 123 I]-CLINDE. In competition studies, PBBS-specific drugs PK11195 and Ro 5-4864 and the CBR specific drug Flumazenil were injected before the radiotracer. In vitro binding studies in adrenal, kidney, and cortex mitochondrial membranes indicated that [ 123 I]-CLINDE binds with high affinity to PBBS, K d = 12.6, 0.20, and 3.84 nM, respectively. The density of binding sites was 163, 5.3, and 0.34 pmol/mg protein, respectively. In vivo biodistribution indicated high uptake in adrenals (5.4), heart (1.5), lungs (1.5), kidney (1.5) %ID/g at 6 h p.i. In the central nervous system (CNS), the olfactory bulbs displayed the highest uptake; up to six times the activity in blood. Pre-administration of unlabeled CLINDE, PK11195 and Ro 5-4864 (1 mg/kg) reduced the uptake of [ 123 I]-CLINDE by 70-55% in olfactory bulbs. In the kidney and heart, a reduction of 60-80% ID/g was observed, while an increase was observed in the adrenals requiring 10 mg/kg for significant displacement. Flumazenil had no effect on uptake in peripheral organs and brain. Metabolite analysis indicated >90% of the radioactivity in the above tissues was intact [ 123 I]-CLINDE. [ 123 I]-CLINDE displays high and selective uptake for the PBBS and warrants further development as a probe for imaging PBBS using single photon emission computed tomography (SPECT). (orig.)

  5. INTERACTION BETWEEN DELTA OPIOID RECEPTORS AND BENZODIAZEPINES IN CO2- INDUCED RESPIRATORY RESPONSES IN MICE

    Science.gov (United States)

    Borkowski, Anne H.; Barnes, Dylan C.; Blanchette, Derek R.; Castellanos, F. Xavier; Klein, Donald F.; Wilson, Donald A.

    2011-01-01

    The false-suffocation hypothesis of panic disorder (Klein, 1993) suggested δ-opioid receptors as a possible source of the respiratory dysfunction manifested in panic attacks occurring in panic disorder (Preter and Klein, 2008). This study sought to determine if a lack of δ-opioid receptors in a mouse model affects respiratory response to elevated CO2, and whether the response is modulated by benzodiazepines, which are widely used to treat panic disorder. In a whole-body plethysmograph, respiratory responses to 5% CO2 were compared between δ-opioid receptor knockout mice and wild-type mice after saline, diazepam (1 mg/kg), and alprazolam (0.3 mg/kg) injection. The results show that lack of δ-opioid receptors does not affect normal response to elevated CO2, but does prevent benzodiazepines from modulating that response. Thus, in the presence of benzodiazepine agonists, respiratory responses to elevated CO2 were enhanced in δ-opioid receptor knockout mice compared to wild-type mice. This suggests an interplay between benzodiazepine receptors and δ-opioid receptors in regulating the respiratory effects of elevated CO2, which might be related to CO2 induced panic. PMID:21561601

  6. Chronic use of benzodiazepines among older adults

    Directory of Open Access Journals (Sweden)

    Jussara Mendonça Alvarenga

    2014-12-01

    Full Text Available OBJECTIVE To analyze the perception of and motivation for the chronic use of benzodiazepine among older adults. METHODS A qualitative study was conducted on 22 older adults living in Bambuí, MG, Southeastern Brazil, who were taking benzodiazepines and had the clinical and cognitive ability to respond to interview questions. The collected data were analyzed on the basis of the “signs, meanings, and actions” model. RESULTS The main reasons pointed out for the use of benzodiazepines were “nervousness”, “sleep problems”, and “worry” due to family and financial problems, everyday problems, and existential difficulties. None of the interviewees said that they used benzodiazepines in a dose higher than that recommended or had been warned by health professionals about any risks of their continuous use. Different strategies were used to obtain the prescription for the medication, and any physician would prescribe it, indicating that a bond was established with the drug and not with the health professional or healthcare service. Obtaining and consuming the medication turned into a crucial issue because benzodiazepine assumes the status of an essential food, which leads users to not think but sleep. It causes a feeling of relief from their problems such as awareness of human finitude and fragility, existential difficulties, and family problems. CONCLUSIONS Benzodiazepine assumes the characteristics of polyvalence among older adults, which extrapolate specific clinical indications, and of essentiality to deal with life’s problems in old age. Although it relieves the “nerves”, the chronic use of benzodiazepines buffers suffering and prevents older adults from going through the suffering. This shows important difficulties in the organization and planning of strategies that are necessary for minimizing the chronic use in this population.

  7. Synthesis of 3-Substituted 1,4-Benzodiazepin-2-ones

    Directory of Open Access Journals (Sweden)

    Kyungjin Kim

    1998-01-01

    Full Text Available The preparation of 3-substituted 1,4-benzodiazepines by benzodiazepine enolate alkylation has been explored. Employing this approach, multigram quantities of benzodiazepine 1 have been prepared for animal studies to evaluate a new approach for the treatment of the autoimmune disease systemic lupus erythematosus (SLE.

  8. Cross-validation, predictive validity, and time course of the Benzodiazepine Dependence Self-Report Questionnaire in a benzodiazepine discontinuation trial.

    NARCIS (Netherlands)

    Oude Voshaar, R.C.; Mol, A.J.J.; Gorgels, W.J.M.J.; Breteler, M.H.M.; Balkom, A.J.L.M. van; Lisdonk, E.H. van de; Kan, C.C.; Zitman, F.G.

    2003-01-01

    The Benzodiazepine Dependence Self-Report Questionnaire (Bendep-SRQ) measures the severity of benzodiazepine (BZ) dependence on four domains: awareness of problematic use, preoccupation with the availability of BZ, lack of compliance with the therapeutic regimen, and withdrawal. Although promising

  9. Lysine and pipecolic acid and some of their derivatives show anticonvulsant activity, and stimulation of benzodiazepine receptor activity

    International Nuclear Information System (INIS)

    Chang, Yung-Feng; Gao, Xue-Min

    1989-01-01

    Benzodiazepines are one of the most widely prescribed drugs in the treatment of anxiety, epilepsy and muscle tension. The natural products lysine and pipecolic acid known to be present in the animal, plant and microorganism, have been shown to be anticonvulsant against pentetrazol (PTZ)-induced seizures in mice. Methyl and ethyl esters of L-lysine and the N-isopropanol derivative of pipecolic acid appear to increase the anticonvulsant potency of the parent compounds, presumably due to their increase in hydrophobicity. Lysine and pipecolic acid showed significant stimulation of specific [ 3 H]flunitrazepam (FZ) binding to mouse brain membranes. This stimulation was enhanced by chloride ions and stereospecific with L-isomer having higher effect. The dose-dependent anticonvulsant activity of lysine and pipecolic acid, and their stimulation of [ 3 H]FZ binding appear to be correlated. The antiepileptic activity lysine, pipecolic acid and their derivatives therefore may be mediated through the γ-aminobutyric acid-benzodiazepine receptor complex

  10. Synthesis of substituted 1,4-diazepines and 1,5-benzodiazepines using an efficient heteropolyacid-catalyzed procedure.

    Science.gov (United States)

    Kaoua, Rachedine; Bennamane, Norah; Bakhta, Saliha; Benadji, Sihame; Rabia, Cherifa; Nedjar-Kolli, Bellara

    2010-12-28

    An efficient and improved procedure for the synthesis of 1,4-diazepine and 1,5-benzodiazepine derivatives via the reaction of ketimine intermediates with aldehydes in the presence of Keggin-type heteropolyacids (HPAs) was developed. High yields and short reaction times were obtained for both electron-releasing and electron-withdrawing substituted 1,4-diazepine  and 1,5-benzodiazepines derivatives.

  11. Synthesis of Substituted 1,4-Diazepines and 1,5-Benzodiazepines Using an Efficient Heteropolyacid-Catalyzed Procedure

    Directory of Open Access Journals (Sweden)

    Sihame Benadji

    2010-12-01

    Full Text Available An efficient and improved procedure for the synthesis of 1,4-diazepine and 1,5-benzodiazepine derivatives via the reaction of ketimine intermediates with aldehydes in the presence of Keggin-type heteropolyacids (HPAs was developed. High yields and short reaction times were obtained for both electron-releasing and electron-withdrawing substituted 1,4-diazepine  and 1,5-benzodiazepines derivatives.

  12. Novel one-pot one-step synthesis of 2'-[(18)F]fluoroflumazenil (FFMZ) for benzodiazepine receptor imaging.

    Science.gov (United States)

    Yoon, Young Hyun; Jeong, Jae Min; Kim, Hyung Woo; Hong, Sung Hyun; Lee, Yun-Sang; Kil, Hee Sup; Chi, Dae Yoon; Lee, Dong Soo; Chung, June-Key; Lee, Myung Chul

    2003-07-01

    We describe the synthesis of 2'-[(18)F]fluoroflumazenil (FFMZ), which differs from the typically used [(18)F]fluoroethylflumazenil (FEFMZ) for benzodiazepine receptor imaging. For one-pot one-step labeling, the precursors, 2'-tosyloxyflumazenil (TFMZ) and 2'-mesyloxyflumazenil (MFMZ), were synthesized in three steps. The precursors were successfully labeled with no-carrier-added (18)F-fluoride which was activated by repeated azeotropic distillation with Kryptofix 2.2.2./potassium carbonate in MeCN. An automated system for labeling and purification of [(18)F]FFMZ was developed. Labeling efficiency and radiochemical purity of [(18)F]FFMZ after synthesis by the automated system were 68% and 98%, respectively. Specific binding of [(18)F]FFMZ to central benzodiazepine receptor of rats was demonstrated by phosphoimaging.

  13. Novel one-pot one-step synthesis of 2'-[18F]fluoroflumazenil (FFMZ) for benzodiazepine receptor imaging

    International Nuclear Information System (INIS)

    Young, Hyun Yoon; Jae, Min Jeong; Hyung, Woo Kim; Sung, Hyun Hong; Lee, Yun-Sang; Hee, Sup Kil; Dae, Yoon Chi; Dong, Soo Lee; Chung, June-Key; Myung, Chul Lee

    2003-01-01

    We describe the synthesis of 2'-[ 18 F]fluoroflumazenil (FFMZ), which differs from the typically used [ 18 F]fluoroethylflumazenil (FEFMZ) for benzodiazepine receptor imaging. For one-pot one-step labeling, the precursors, 2'-tosyloxyflumazenil (TFMZ) and 2'-mesyloxyflumazenil (MFMZ), were synthesized in three steps. The precursors were successfully labeled with no-carrier-added 18 F-fluoride which was activated by repeated azeotropic distillation with Kryptofix 2.2.2./potassium carbonate in MeCN. An automated system for labeling and purification of [ 18 F]FFMZ was developed. Labeling efficiency and radiochemical purity of [ 18 F]FFMZ after synthesis by the automated system were 68% and 98%, respectively. Specific binding of [ 18 F]FFMZ to central benzodiazepine receptor of rats was demonstrated by phosphoimaging

  14. Benzodiazepines - Their role in aggression and why GPs should prescribe with caution.

    Science.gov (United States)

    Jones, Katy A; Nielsen, Suzanne; Bruno, Raimondo; Frei, Matthew; Lubman, Dan I

    2011-11-01

    Benzodiazepines are widely prescribed in Australia, despite concerns about their potential for abuse and dependence. Paradoxical reactions, disinhibition and amnesia are all associated with benzodiazepine use, misuse and intoxication. While violent and aggressive behaviour may be a consequence of such disinhibition, there is limited information available regarding the links between benzodiazepine use and violence. This article aims to examine the existing evidence on the relationship between benzodiazepines, violence and aggression. While current evidence suggests that benzodiazepines rarely induce violence, it is important to note that the available literature is limited in its scope and that benzodiazepine related violence is often severe and of potential concern to frontline workers. Mediating risk factors for benzodiazepine related violence include concurrent alcohol use, benzodiazepine dose, a history of aggression and underlying impulsivity. Comprehensive assessment and alternate nonpharmacological treatment options should be considered before prescribing benzodiazepines within primary care.

  15. [Physical performance and sedation: comparative study of the effects of a benzodiazepine (temazepam) and of a non-benzodiazepine hypnotic (zolpidem)].

    Science.gov (United States)

    Gremion, G; Sutter-Weyrich, C; Rostan, A; Forster, A

    1992-09-01

    It is well-known that many athletes experience some form of precompetition stress that may result in insomnia during the night before their competition. Yet, sleep withdrawal even if only partial, has a negative influence on performance, particularly when the type of exercise requires good psychomotor performance The purpose of the present study was to investigate whether the intake of a hypnotic drug would have negative effects on physical performance capacity. The authors have compared the effects of oral temazepam, a medium half-life benzodiazepine vs oral zolpidem, a short half-life non-benzodiazepine drug, vs placebo. A randomized double-blind trial was used to assess endurance, resistance, strength and coordination in 26 athletes. The results did not show any differences between the three groups, neither in physical performance characteristic nor in coordination. It is concluded that as regards the performance capacity, there is no risk for stressed athletes to use sleep inducers the night before their competition.

  16. The impact of benzodiazepine use on methadone maintenance treatment outcomes.

    Science.gov (United States)

    Brands, Bruna; Blake, Joan; Marsh, David C; Sproule, Beth; Jeyapalan, Renuka; Li, Selina

    2008-01-01

    The purposes of this study were to examine predictors of benzodiazepine use among methadone maintenance treatment patients, to determine whether baseline benzodiazepine use influenced ongoing use during methadone maintenance treatment, and to assess the effect of ongoing benzodiazepine use on treatment outcomes (i.e., opioid and cocaine use and treatment retention). A retrospective chart review of 172 methadone maintenance treatment patients (mean age = 34.6 years; standard deviation = 8.5 years; 64% male) from January 1997 to December 1999 was conducted. At baseline, 29% were "non-users" (past year) of benzodiazepine, 36% were "occasional users," and 35% were "regular/problem users." Regular/problem users were more likely to have started opioid use with prescription opioids, experienced more overdoses, and reported psychiatric comorbidity. Being female, more years of opioid use, and a history of psychiatric treatment were significant predictors of baseline benzodiazepine use. Ongoing benzodiazepine users were more likely to have opioid-positive and cocaine-positive urine screens during methadone maintenance treatment. Only ongoing cocaine use was negatively related to retention. Benzodiazepine use by methadone maintenance treatment patients is associated with a more complex clinical picture and may negatively influence treatment outcomes.

  17. Characterization of high affinity [3H]triazolam binding in rat brain

    International Nuclear Information System (INIS)

    Earle, M.; Concas, A.; Yamamura, H.I.

    1986-01-01

    The hypnotic Triazolam (TZ), a triazolo (1,4)-benzodiazepine, displays a short physiological half life and has been used for the treatment of insomnia related to anxiety states. Specific binding properties of this recently tritiated TZ were characterized. The authors major objectives were the direct measurement of the temperature dependence and the GABA effect on [ 3 H]TZ binding. Saturation studies showed a shift to lower affinity at 37 0 C (K/sub d/ = 0.25 +/- 0.01 nM at O 0 C; K/sub d/ = 1.46 +/- 0.03 nM at 37 0 C) while the B/sub max/ values remained unchanged (1003 +/- 37 fmoles/mg prot. at 0 0 C and 1001 +/- 43 fmoles/mg prot. at 37 0 C). Inhibition studies showed that [ 3 H]TZ binding displayed no GABA shift at 0 0 C(K/sub i/ 0.37 +/- 0.03 nM/- GABA and K/sub i/ = 0.55 +/- 0.13 nM/+GABA) but a nearly two-fold shift was apparent at 37 0 C (K/sub i/ = 2.92 +/- 0.2 nM/-GABA; K/sub i/ = 1.37 +/- 0.11 mM/+GABA). These results were also confirmed by saturation studies in the presence or absence of GABA showing a shift to higher affinity in the presence of GABA only at 37 0 C. In Ro 15-1788/[ 3 H]TZ competition experiments the presence of GABA did not affect the inhibitory potency of Ro 15-1788 on [ 3 H]TZ binding at both temperatures. In conclusion [ 3 H]TZ binding showed an extremely high affinity for benzodiazepine receptors. In contrast to reported literature, the findings suggest that TZ interacts with benzodiazepine receptors similar to other benzodiazepine agonists

  18. Identification, characterization and potent antitumor activity of ECO-4601, a novel peripheral benzodiazepine receptor ligand.

    Science.gov (United States)

    Gourdeau, Henriette; McAlpine, James B; Ranger, Maxime; Simard, Bryan; Berger, Francois; Beaudry, Francis; Farnet, Chris M; Falardeau, Pierre

    2008-05-01

    ECO-4601 is a structurally novel farnesylated dibenzodiazepinone discovered through DECIPHER technology, Thallion's proprietary drug discovery platform. The compound was shown to have a broad cytotoxic activity in the low micromolar range when tested in the NCI 60 cell line panel. In the work presented here, ECO-4601 was further evaluated against brain tumor cell lines. Preliminary mechanistic studies as well as in vivo antitumor evaluation were performed. Since ECO-4601 has a benzodiazepinone moiety, we first investigated if it binds the central and/or peripheral benzodiazepine receptors. ECO-4601 was tested in radioligand binding assays on benzodiazepine receptors obtained from rat hearts. The ability of ECO-4601 to inhibit the growth of CNS cancers was evaluated on a panel of mouse, rat and human glioma cell lines using a standard MTT assay. Antitumor efficacy studies were performed on gliomas (rat and human), human breast and human prostate mouse tumor xenografts. Antitumor activity and pharmacokinetic analysis of ECO-4601 was evaluated following intravenous (i.v.), subcutaneous (s.c.), and intraperitoneal (i.p.) bolus administrations. ECO-4601 was shown to bind the peripheral but not the central benzodiazepine receptor and inhibited the growth of CNS tumor cell lines. Bolus s.c. and i.p. administration gave rise to low but sustained drug exposure, and resulted in moderate to significant antitumor activity at doses that were well tolerated. In a rat glioma (C6) xenograft model, ECO-4601 produced up to 70% tumor growth inhibition (TGI) while in a human glioma (U-87MG) xenograft, TGI was 34%. Antitumor activity was highly significant in both human hormone-independent breast (MDA-MB-231) and prostate (PC-3) xenografts, resulting in TGI of 72 and 100%, respectively. On the other hand, i.v. dosing was followed by rapid elimination of the drug and was ineffective. Antitumor efficacy of ECO-4601 appears to be associated with the exposure parameter AUC and/or sustained

  19. Cross-validation, predictive validity and time course of the Benzodiazepine Dependence Self-Report Questionnaire (Bendep-SRQ) in a benzodiazepine discontinuation trial

    NARCIS (Netherlands)

    Oude Voshaar, R.C.; Mol, A.J.J.; Gorgels, W.J.M.J.; Breteler, M.H.M.; Balkom, A.J.L.M. van; Lisdonk, E.H. van de; Zitman, F.G.

    2003-01-01

    The Benzodiazepine Dependence Self-Report Questionnaire (Bendep-SRQ) measures the severity of benzodiazepine (BZ) dependence on four domains: awareness of problematic use, preoccupation with the availability of BZ, lack of compliance with the therapeutic regimen, and withdrawal. Although promising

  20. [18F]Fluoroethylflumazenil: a novel tracer for PET imaging of human benzodiazepine receptors

    International Nuclear Information System (INIS)

    Gruender, G.; Lange-Asschenfeldt, C.; Vernaleken, I.; Lueddens, H.; Siessmeier, T.; Buchholz, H.-G.; Bartenstein, P.; Stoeter, P.; Drzezga, A.; Roesch, F.

    2001-01-01

    5-(2'-[ 18 F]Fluoroethyl)flumazenil ([ 18 F]FEF) is a fluorine-18 labelled positron emission tomography (PET) tracer for central benzodiazepine receptors. Compared with the established [ 11 C]flumazenil, it has the advantage of the longer half-life of the fluorine-18 label. After optimisation of its synthesis and determination of its in vitro receptor affinities, we performed first PET studies in humans. PET studies in seven healthy human volunteers were performed on a Siemens ECAT EXACT whole-body scanner after injection of 100-280 MBq [ 18 F]FEF. In two subjects, a second PET scan was conducted after pretreatment with unlabelled flumazenil (1 mg or 2.5 mg i.v., 3 min before tracer injection). A third subject was studied both with [ 18 F]FEF and with [ 11 C]flumazenil. Brain radioactivity was measured for 60-90 min p.i. and analysed with a region of interest-oriented approach and on a voxelwise basis with spectral analysis. Plasma radioactivity was determined from arterial blood samples and metabolites were determined by high-performance liquid chromatography. In human brain, maximum radioactivity accumulation was observed 4±2 min p.i., with a fast clearance kinetics resulting in 50% and 20% of maximal activities at about 10 and 30 min, respectively. [ 18 F]FEF uptake followed the known central benzodiazepine receptor distribution in the human brain (occipital cortex >temporal cortex >cerebellum >thalamus >pons). Pretreatment with unlabelled flumazenil resulted in reduced tracer uptake in all brain areas except for receptor-free reference regions like the pons. Parametric images of distribution volume and binding potential generated on a voxelwise basis revealed two- to three-fold lower in vivo receptor binding of [ 18 F]FEF compared with [ 11 C]flumazenil, while relative uptake of [ 18 F]FEF was higher in the cerebellum, most likely owing to its relatively higher affinity for benzodiazepine receptors containing the α6 subunit. Metabolism of [ 18 F]FEF was very

  1. Balneotherapy Together with a Psychoeducation Program for Benzodiazepine Withdrawal: A Feasibility Study

    Science.gov (United States)

    De Maricourt, P.; Hergueta, Th.; Galinowski, A.; Salamon, R.; Diallo, A.; Vaugeois, C.; Lépine, J. P.; Olié, J. P.

    2016-01-01

    Benzodiazepines should be prescribed on a short-term basis, but a significant proportion of patients (%) use them for more than 6 months, constituting a serious public health issue. Indeed, few strategies are effective in helping patients to discontinue long-term benzodiazepine treatments. The aim of this study was to assess the feasibility and the impact of a program including cognitive behavioural therapy, psychoeducation, and balneotherapy in a spa resort to facilitate long-term discontinuation of benzodiazepines. We conducted a prospective multicentre cohort study. Patients with long-term benzodiazepine use were recruited with the aim of anxiolytic withdrawal by means of a psychoeducational program and daily balneotherapy during 3 weeks. The primary efficacy outcome measure was benzodiazepine use 6 months after the program, compared to use at baseline. A total of 70 subjects were enrolled. At 6 months, overall benzodiazepine intake had decreased by 75.3%, with 41.4% of patients completely stopping benzodiazepine use. The results also suggest a significantly greater improvement in anxiety and depression symptoms among patients who discontinued benzodiazepines compared to patients who only reduced their use. Our findings suggest that balneotherapy in association with a psychoeducative program is efficient in subjects with benzodiazepine addiction. PMID:27956923

  2. Balneotherapy Together with a Psychoeducation Program for Benzodiazepine Withdrawal: A Feasibility Study

    Directory of Open Access Journals (Sweden)

    P. De Maricourt

    2016-01-01

    Full Text Available Benzodiazepines should be prescribed on a short-term basis, but a significant proportion of patients (% use them for more than 6 months, constituting a serious public health issue. Indeed, few strategies are effective in helping patients to discontinue long-term benzodiazepine treatments. The aim of this study was to assess the feasibility and the impact of a program including cognitive behavioural therapy, psychoeducation, and balneotherapy in a spa resort to facilitate long-term discontinuation of benzodiazepines. We conducted a prospective multicentre cohort study. Patients with long-term benzodiazepine use were recruited with the aim of anxiolytic withdrawal by means of a psychoeducational program and daily balneotherapy during 3 weeks. The primary efficacy outcome measure was benzodiazepine use 6 months after the program, compared to use at baseline. A total of 70 subjects were enrolled. At 6 months, overall benzodiazepine intake had decreased by 75.3%, with 41.4% of patients completely stopping benzodiazepine use. The results also suggest a significantly greater improvement in anxiety and depression symptoms among patients who discontinued benzodiazepines compared to patients who only reduced their use. Our findings suggest that balneotherapy in association with a psychoeducative program is efficient in subjects with benzodiazepine addiction.

  3. Symptom-triggered benzodiazepine therapy for alcohol withdrawal syndrome in the emergency department: a comparison with the standard fixed dose benzodiazepine regimen.

    LENUS (Irish Health Repository)

    Cassidy, Eugene M

    2012-10-01

    The aim of the study was to compare symptom-triggered and standard benzodiazepine regimens for the treatment of alcohol withdrawal syndrome in an emergency department clinical decision unit. The authors found that the symptom-triggered approach reduced cumulative benzodiazepine dose and length of stay.

  4. Analytical methodologies for the determination of benzodiazepines in biological samples.

    Science.gov (United States)

    Persona, Karolina; Madej, Katarzyna; Knihnicki, Paweł; Piekoszewski, Wojciech

    2015-09-10

    Benzodiazepine drugs belong to important and most widely used medicaments. They demonstrate such therapeutic properties as anxiolytic, sedative, somnifacient, anticonvulsant, diastolic and muscle relaxant effects. However, despite the fact that benzodiazepines possess high therapeutic index and are considered to be relatively safe, their use can be dangerous when: (1) co-administered with alcohol, (2) co-administered with other medicaments like sedatives, antidepressants, neuroleptics or morphine like substances, (3) driving under their influence, (4) using benzodiazepines non-therapeutically as drugs of abuse or in drug-facilitated crimes. For these reasons benzodiazepines are still studied and determined in a variety of biological materials. In this article, sample preparation techniques which have been applied in analysis of benzodiazepine drugs in biological samples have been reviewed and presented. The next part of the article is focused on a review of analytical methods which have been employed for pharmacological, toxicological or forensic study of this group of drugs in the biological matrices. The review was preceded by a description of the physicochemical properties of the selected benzodiazepines and two, very often coexisting in the same analyzed samples, sedative-hypnotic drugs. Copyright © 2015. Published by Elsevier B.V.

  5. An audit of prescribing practices for benzodiazepines and Z-drugs.

    LENUS (Irish Health Repository)

    Cadogan, C

    2015-03-01

    Concerns persist over the use of benzodiazepines and Z-drugs in Ireland. A prospective prescription audit was conducted in 81 community pharmacies across Ireland over a four week period. The study sought to assess the level of prescription compliance with key components of benzodiazepine and Z-drug prescribing guidelines. 28% of audit booklets issued were returned, yielding data on 4,418 prescriptions. The findings suggest that little progress has been made in improving the prescribing of benzodiazepines and Z-drugs in Ireland in the decade since publication of the Benzodiazepine Committee\\'s report. Fewer than one fifth of prescriptions (18.8%) were fully compliant with the assessment criteria and the majority (53.7%) had multiple discrepancies. This study highlights the importance of monitoring and auditing benzodiazepine and Z-drug prescribing practices. Interventions involving patients, prescribers and pharmacists are required to improve the prescribing and use of these medications in Ireland.

  6. Bromine-75-labeled 1,4-benzodiazepines: potential agents for the mapping of benzodiazepine receptors in vivo: concise communication

    Energy Technology Data Exchange (ETDEWEB)

    Scholl, H.; Kloster, G.; Stoecklin, G.

    1983-05-01

    We have prepared four different 1,4-benzodiazepines, labeled at C-7 with the 1.6-hr positron emitter Br-75 or the 57-hr gamma emitter Br-77, as potential radio-pharmaceuticals for the mapping of cerebral benzodiazepine receptor areas. The triazene method was used and optimized. Yields at the no-carrier-added level were 20%. (7-/sup 75/Br)-5-(2-flophenyl)-1-methyl-1,3-dihydro-2H-1,4-benzodiazepine-2-one (Br-75 BFB) was isolated with a minimum specific activity of 20,000 Ci/mmole. Biodistribution in mice shows that BFB is taken up rapidly by the brain and is retained there at useful concentrations for significant periods of time. The maximum uptake is observed at 0.25 min. Brain-to-blood concentration ratios are larger than 2 during the interval (0.25 to 10 min) investigated.

  7. Allosteric ligands and their binding sites define γ-aminobutyric acid (GABA) type A receptor subtypes.

    Science.gov (United States)

    Olsen, Richard W

    2015-01-01

    GABAA receptors (GABA(A)Rs) mediate rapid inhibitory transmission in the brain. GABA(A)Rs are ligand-gated chloride ion channel proteins and exist in about a dozen or more heteropentameric subtypes exhibiting variable age and brain regional localization and thus participation in differing brain functions and diseases. GABA(A)Rs are also subject to modulation by several chemotypes of allosteric ligands that help define structure and function, including subtype definition. The channel blocker picrotoxin identified a noncompetitive channel blocker site in GABA(A)Rs. This ligand site is located in the transmembrane channel pore, whereas the GABA agonist site is in the extracellular domain at subunit interfaces, a site useful for low energy coupled conformational changes of the functional channel domain. Two classes of pharmacologically important allosteric modulatory ligand binding sites reside in the extracellular domain at modified agonist sites at other subunit interfaces: the benzodiazepine site and the high-affinity, relevant to intoxication, ethanol site. The benzodiazepine site is specific for certain GABA(A)R subtypes, mainly synaptic, while the ethanol site is found at a modified benzodiazepine site on different, extrasynaptic, subtypes. In the transmembrane domain are allosteric modulatory ligand sites for diverse chemotypes of general anesthetics: the volatile and intravenous agents, barbiturates, etomidate, propofol, long-chain alcohols, and neurosteroids. The last are endogenous positive allosteric modulators. X-ray crystal structures of prokaryotic and invertebrate pentameric ligand-gated ion channels, and the mammalian GABA(A)R protein, allow homology modeling of GABA(A)R subtypes with the various ligand sites located to suggest the structure and function of these proteins and their pharmacological modulation. © 2015 Elsevier Inc. All rights reserved.

  8. Pharmacological evaluation of [{sup 123}I]-CLINDE: a radioiodinated imidazopyridine-3-acetamide for the study of peripheral benzodiazepine binding sites (PBBS)

    Energy Technology Data Exchange (ETDEWEB)

    Mattner, Filomena; Katsifis, Andrew [Australian Nuclear Science and Technology Organisation, Radiopharmaceuticals Research Institute, PMB 1 Menai, N.S.W., Sydney (Australia); Mardon, Karine [The University of Queensland, Centre for Studies in Drug Disposition, Brisbane (Australia)

    2008-04-15

    The study aims to evaluate the iodinated imidazopyridine, N',N'-diethyl-6-Chloro-(4'-[{sup 123}I]iodophenyl)imidazo[1,2-a]pyridine-3-acetamide ([{sup 123}I]-CLINDE) as a tracer for the study of peripheral benzodiazepine binding sites (PBBS). In vitro studies were performed using membrane homogenates and sections from kidney, adrenals, and brain cortex of Sprague-Dawley (SD) rats and incubated with [{sup 123}I]-CLINDE. For in vivo studies, the rats were injected with [{sup 123}I]-CLINDE. In competition studies, PBBS-specific drugs PK11195 and Ro 5-4864 and the CBR specific drug Flumazenil were injected before the radiotracer. In vitro binding studies in adrenal, kidney, and cortex mitochondrial membranes indicated that [{sup 123}I]-CLINDE binds with high affinity to PBBS, K{sub d} = 12.6, 0.20, and 3.84 nM, respectively. The density of binding sites was 163, 5.3, and 0.34 pmol/mg protein, respectively. In vivo biodistribution indicated high uptake in adrenals (5.4), heart (1.5), lungs (1.5), kidney (1.5) %ID/g at 6 h p.i. In the central nervous system (CNS), the olfactory bulbs displayed the highest uptake; up to six times the activity in blood. Pre-administration of unlabeled CLINDE, PK11195 and Ro 5-4864 (1 mg/kg) reduced the uptake of [{sup 123}I]-CLINDE by 70-55% in olfactory bulbs. In the kidney and heart, a reduction of 60-80% ID/g was observed, while an increase was observed in the adrenals requiring 10 mg/kg for significant displacement. Flumazenil had no effect on uptake in peripheral organs and brain. Metabolite analysis indicated >90% of the radioactivity in the above tissues was intact [{sup 123}I]-CLINDE. [{sup 123}I]-CLINDE displays high and selective uptake for the PBBS and warrants further development as a probe for imaging PBBS using single photon emission computed tomography (SPECT). (orig.)

  9. Binding interactions of convulsant and anticonvulsant gamma-butyrolactones and gamma-thiobutyrolactones with the picrotoxin receptor

    International Nuclear Information System (INIS)

    Holland, K.D.; McKeon, A.C.; Covey, D.F.; Ferrendelli, J.A.

    1990-01-01

    Alkyl-substituted gamma-butyrolactones (GBLs) and gamma-thiobutyrolactones (TBLs) are neuroactive chemicals. beta-Substituted compounds are convulsant, whereas alpha-alkyl substituted GBLs and TBLs are anticonvulsant. The structural similarities between beta-alkyl GBLs and the convulsant picrotoxinin suggested that alkyl substituted GBLs and TBLs act at the picrotoxin receptor. To test this hypothesis we examined the interactions of convulsant and anticonvulsant GBLs and TBLs with the picrotoxin, benzodiazepine and gamma-aminobutyric acid (GABA) binding sites of the GABA receptor complex. All of these convulsants and anticonvulsants studied competitively displaced 35S-t-butylbicyclophosphorothionate (35S-TBPS), a ligand that binds to the picrotoxin receptor. This inhibition of 35S-TBPS binding was not blocked by the GABA antagonist bicuculline methobromide. The convulsant GBLs and TBLs also partially inhibited [3H]muscimol binding to the GABA site and [3H]flunitrazepam binding to the benzodiazepine site, but they did so at concentrations substantially greater than those that inhibited 35S-TBPS binding. The anticonvulsant GBLs and TBLs had no effect on either [3H]muscimol or [3H]flunitrazepam binding. In contrast to the GBLs and TBLs, pentobarbital inhibited TBPS binding in a manner that was blocked by bicuculline methobromide, and it enhanced both [3H]flunitrazepam and [3H]muscimol binding. Both ethosuximide and tetramethylsuccinimide, neuroactive compounds structurally similar to GBLs, competitively displaced 35S-TBPS from the picrotoxin receptor and both compounds were weak inhibitors of [3H] muscimol binding. In addition, ethosuximide also partially diminished [3H]flunitrazepam binding. These data demonstrate that the site of action of alkyl-substituted GBLs and TBLs is different from that of GABA, barbiturates and benzodiazepines

  10. Phenobarbital compared to benzodiazepines in alcohol withdrawal treatment: A register-based cohort study of subsequent benzodiazepine use, alcohol recidivism and mortality.

    Science.gov (United States)

    Askgaard, Gro; Hallas, Jesper; Fink-Jensen, Anders; Molander, Anna Camilla; Madsen, Kenneth Grønkjær; Pottegård, Anton

    2016-04-01

    Long-acting benzodiazepines such as chlordiazepoxide are recommended as first-line treatment for alcohol withdrawal. These drugs are known for their abuse liability and might increase alcohol consumption among problem drinkers. Phenobarbital could be an alternative treatment option, possibly with the drawback of a more pronounced acute toxicity. We evaluated if phenobarbital compared to chlordiazepoxide decreased the risk of subsequent use of benzodiazepines, alcohol recidivism and mortality. The study was a register-based cohort study of patients admitted for alcohol withdrawal 1998-2013 and treated with either phenobarbital or chlordiazepoxide. Patients were followed for one year. We calculated hazard ratios (HR) for benzodiazepine use, alcohol recidivism and mortality associated with alcohol withdrawal treatment, while adjusting for confounders. A total of 1063 patients treated with chlordiazepoxide and 1365 patients treated with phenobarbital were included. After one year, the outcome rates per 100 person-years in the phenobarbital versus the chlordiazepoxide cohort were 9.20 vs. 5.13 for use of benzodiazepine, 37.9 vs. 37.9 for alcohol recidivism and 29 vs. 59 for mortality. Comparing phenobarbital to chlordiazepoxide treated, the HR of subsequent use of benzodiazepines was 1.56 (95%CI 1.05-2.30). Similarly, the HR for alcohol recidivism was 0.99 (95%CI 0.84-1.16). Lastly, the HR for 30-days and 1 year mortality was 0.25 (95%CI 0.08-0.78) and 0.51 (95%CI 0.31-0.86). There was no decreased risk of subsequent benzodiazepine use or alcohol recidivism in patients treated with phenobarbital compared to chlordiazepoxide. Phenobarbital treatment was associated with decreased mortality, which might be confounded by somatic comorbidity among patients receiving chlordiazepoxide. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  11. An Update on the Synthesis of Pyrrolo[1,4]benzodiazepines

    Directory of Open Access Journals (Sweden)

    George Varvounis

    2016-01-01

    Full Text Available Pyrrolo[1,4]benzodiazepines are tricyclic compounds that are considered “privileged structures” since they possess a wide range of biological activities. The first encounter with these molecules was the isolation of anthramycin from cultures of Streptomyces, followed by determination of the X-ray crystal structure of the molecule and a study of its interaction with DNA. This opened up an intensive synthetic and biological study of the pyrrolo[2,1-c][1,4]benzodiazepines that has culminated in the development of the dimer SJG-136, at present in Phase II clinical trials. The synthetic efforts have brought to light some new synthetic methodology, while the contemporary work is focused on building trimeric pyrrolo[2,1-c][1,4]benzodiazepines linked together by various heterocyclic and aliphatic chains. It is the broad spectrum of biological activities of pyrrolo[1,2-a][1,4]benzodiazepines that has maintained the interest of researchers to date whereas several derivatives of the even less studied pyrrolo[1,2-d][1,4]benzodiazepines were found to be potent non-nucleoside HIV-1 reverse transcriptase inhibitors. The present review is an update on the synthesis of pyrrolo[2,1-c][1,4]benzodiazepines since the last major review of 2011, while the overview of the synthesis of the other two tricyclic isomers is comprehensive.

  12. Phenobarbital compared to benzodiazepines in alcohol withdrawal treatment

    DEFF Research Database (Denmark)

    Askgaard, Gro; Hallas, Jesper; Fink-Jensen, Anders

    2016-01-01

    BACKGROUND: Long-acting benzodiazepines such as chlordiazepoxide are recommended as first-line treatment for alcohol withdrawal. These drugs are known for their abuse liability and might increase alcohol consumption among problem drinkers. Phenobarbital could be an alternative treatment option......, possibly with the drawback of a more pronounced acute toxicity. We evaluated if phenobarbital compared to chlordiazepoxide decreased the risk of subsequent use of benzodiazepines, alcohol recidivism and mortality. METHODS: The study was a register-based cohort study of patients admitted for alcohol...... withdrawal 1998-2013 and treated with either phenobarbital or chlordiazepoxide. Patients were followed for one year. We calculated hazard ratios (HR) for benzodiazepine use, alcohol recidivism and mortality associated with alcohol withdrawal treatment, while adjusting for confounders. RESULTS: A total...

  13. The GABAA receptor complex in hepatic encephalopathy. Autoradiographic evidence for the presence of elevated levels of a benzodiazepine receptor ligand

    Energy Technology Data Exchange (ETDEWEB)

    Basile, A.S.; Ostrowski, N.L.; Gammal, S.H.; Jones, E.A.; Skolnick, P. (National Institutes of Health, Bethesda, MD (USA))

    1990-02-01

    Autoradiographic analysis was used to examine radioligand binding to benzodiazepine (BZ) and GABAA receptors in the brains of rabbits with hepatic encephalopathy (HE). Thin sections of whole brain from normal rabbits and rabbits with HE were mounted on slides and subdivided into two groups. One group was washed before incubation with radioligand, while the second group was not prewashed. (3H)Flunitrazepam binding to BZ receptors was decreased by 22% to 42% (p less than 0.05) in the cerebral cortex, superior and inferior colliculi, and cerebellum of unwashed sections from rabbits with HE compared to all other groups. The binding of (3H)Ro 15-1788 to unwashed sections from rabbits with HE was reduced by a similar degree (18% to 37%, p less than 0.05) in the cerebral cortex, hippocampus, superior colliculus, and cerebellar cortex. Incubation of sections with the GABA-mimetic muscimol and NaCl produced an additional decrease in (3H)flunitrazepam binding to the cortex and hippocampus (25% to 31%, p less than 0.05) in unwashed HE rabbit brain, but increased radioligand binding (27% to 71%, p less than 0.05) to several regions in control rabbits. No changes in radioligand binding to either GABAA or peripheral benzodiazepine receptors was observed between HE and control rabbit sections. These findings are consistent with previous electrophysiologic and neurochemical observations indicating no significant changes in either the function or density of GABAA or BZ receptors in this model of HE. Further, they indicate that a reversible BZ receptor ligand with agonist properties is present in the brain in HE. This substance may contribute to the enhancement of GABAergic tone observed in this syndrome.

  14. Evaluation of C.L.I.N.D.E. as potent peripheral-type benzodiazepine receptor tracer in a rat model of micro-glial activation

    Energy Technology Data Exchange (ETDEWEB)

    Arlicot, N.; Guilloteau, D.; Chalon, S. [Institut National de la Sante et de la Recherche Medicale (INSERM), U619, 37 - Tours (France); Universite Francois Rabelais de Tours, 37 (France); Katsifis, A.; Mattner, F. [ANSTO, Sydney (Australia)

    2008-02-15

    The peripheral-type benzodiazepine receptors (P.B.R.) are localized in mitochondria of glial cells and are very low expressed in normal brain. Their expression rises after micro-glial activation consecutive to brain injury. Accordingly, P.B.R. are potential targets to evaluate neuro inflammatory changes in a variety of C.N.S. disorders. To date no effective tool is available to explore P.B.R. by SPECT. We characterized here 6-chloro-2-(4 iodophenyl)-3-(N,N-diethyl)-imidazo[1,2-a]pyridine- 3-acetamide, C.L.I.N.D.E., in a rat model of excitotoxic lesion. Excitotoxicity was induced in male Wistar rats by unilateral intra striatal injection of different amounts of quinolinic acid (Q.A.: 75, 150 or 300 nmol). One week later, 2 groups of rats (n = 5-6/group) were i.v. injected with [{sup 125}I]-C.L.I.N.D.E. (0.4 MBq), one group being pre-injected with P.K.11195 (5 mg/kg). Brains were removed 30 min after tracer injection and the radioactivity of cerebral areas measured. Complementary ex vivo autoradiography and immunohistochemical studies using O.X.-42 were performed on brain sections In the control group, [{sup 125}I]-C.L.I.N.D.E. binding was significantly higher ( p < 0.001) in lesioned than that in intact side (striatum: 0.552 {+-} 0.109 vs. 0.123 {+-} 0.012% I.D./g tissue; cortex: 0.385 {+-} 0.126 vs. 0.131 {+-} 0.007% with 300 nmol Q.A.). This binding disappeared in rats pretreated with P.K.11195 ( p < 0.001), showing specific binding of C.L.I.N.D.E. to P.B.R.. Ex vivo autoradiography and immunohistochemistry were consistent with this, revealing a spatial correspondence between radioactivity signal and activated micro-glia. Regression analysis yielded a significant correlation ( p < 0.001) between the ligand binding and the dose of Q.A.. These results demonstrate that C.L.I.N.D.E. is suitable for P.B.R. in vivo SPECT imaging to explore their involvement in neuro degenerative disorders associated with micro-glial activation. (authors)

  15. The GABA-A benzodiazepine receptor complex: Role of pet and spect in neurology and psychiatry

    International Nuclear Information System (INIS)

    Juengling, F.D.; Schaefer, M.; Heinz, A.

    2002-01-01

    Nuclear medicine imaging techniques such as positron emission tomography (PET) and single photon emission tomography (SPECT) for selective depiction of GABA-A-benzodiazepine receptor (GBZR) binding are complementary investigations in the diagnostic process of neurological and psychiatric disorders. This review summarizes the current knowledge about options and limitations of PET and SPECT for in vivo diagnostics in neurology and psychiatry. The growing importance of GBZR-imaging for the understanding of pathophysiology and pharmacological treatment in different psychiatric syndromes is discussed. (orig.) [de

  16. Electroacupuncture for tapering off long-term benzodiazepine use: study protocol of randomized controlled trial.

    Science.gov (United States)

    Yeung, Wing-Fai; Chung, Ka-Fai; Zhang, Zhang-Jin; Chan, Wai-Chi; Zhang, Shi-Ping; Ng, Roger Man-Kin; Chan, Connie Lai-Wah; Ho, Lai-Ming; Yu, Yee-Man; Lao, Li-Xing

    2017-03-31

    Conventional approaches for benzodiazepine tapering have their limitations. Anecdotal studies have shown that acupuncture is a potential treatment for facilitating successful benzodiazepine tapering. As of today, there was no randomized controlled trial examining its efficacy and safety. The purpose of the study is to evaluate the efficacy of using electroacupuncture as an adjunct treatment to gradual tapering of benzodiazepine doses in complete benzodiazepine cessation in long-term benzodiazepine users. The study protocol of a randomized, assessor- and subject-blinded, controlled trial is presented. One hundred and forty-four patients with histories of using benzodiazepines in ≥50% of days for more than 3 months will be randomly assigned in a 1:1 ratio to receive either electroacupuncture or placebo electroacupuncture combined with gradual benzodiazepine tapering schedule. Both experimental and placebo treatments will be delivered twice per week for 4 weeks. Major assessments will be conducted at baseline, week 6 and week 16 post-randomization. Primary outcome is the cessation rate of benzodiazepine use. Secondary outcomes include the percentage change in the doses of benzodiazepine usage and the severity of withdrawal symptoms experienced based on the Benzodiazepine Withdrawal Symptom Questionnaire, insomnia as measured by the Insomnia Severity Index, and anxiety and depressive symptoms as evaluated by the Hospital Anxiety and Depression Scale. Adverse events will also be measured at each study visit. Results of this study will provide high quality evidence of the efficacy and safety of electroacupuncture as an adjunct treatment for benzodiazepine tapering in long-term users. ClinicalTrials.gov NCT02475538 .

  17. Genetic and psychosocial factors for benzodiazepine addiction. An analysis based on the results of the authors’ own research conducted in a group of benzodiazepine addicted and non-addicted individuals

    Directory of Open Access Journals (Sweden)

    Anna Konopka

    2017-03-01

    Full Text Available Purpose: In spite of the fact that the addictive potential of benzodiazepine (BDZ drugs has been known for a long time, benzodiazepine addiction remains a common problem for psychiatry to deal with. The etiology of benzodiazepine addiction is very complex. Among the risk factors, the course of the treatment, demographic status and psychological features of a patient seem to play an important role. The aim of this study was to investigate both psychological and genetic factors differentiating benzodiazepine addicts from non-addicted users.Methods: We analysed a cohort of 120 individuals treated with benzodiazepines divided into two groups: benzodiazepine addicts and non-addicted benzodiazepine users (the control group. In both groups we measured genetic polymorphisms of GABA A2 and MAOA. In both groups some psychometric measurements were performed – we investigated the level of depression, anxiety as a state and as a trait, personality features and the dominant coping style using the Beck Depression Scale, Hamilton Anxiety Scale, Five-Factor Personality Inventory NEO-FFI and the Coping Inventory for Stressful Situations [4,10,17,36,41,44].Results: There are some psychological and situational risk factors for benzodiazepine addiction such as high neuroticism, introversion and lack of the ability to release tension through interpersonal contacts, dominance of emotional coping style and high accumulation of critical life events during both childhood and adulthood. The genetic background still remains a field for further exploration.

  18. Pattern of utilization of benzodiazepines in patients with hypertension: A pilot study

    Directory of Open Access Journals (Sweden)

    Divac Nevena

    2006-01-01

    Full Text Available Background/Aim. The analysis of drug prescribing in general practice in Serbia showed that the use of benzodiazepines is most frequently associated with hypertension. The aim of this study was to establish the correlation of the characteristics of patients with hypertension to antihypertensive drug therapy, and the intake of benzodiazepines. Methods. A special questionnaire was used for interviewing the patients (n = 171 chronically treated for hypertenson. Statistical tests used were χ2-test and Student's t-test. Results. No differences were noted in terms of age, gender, education, body weight, smoking habits and blood pressure (155±4.9/100±2.7 mmHg vs. 160±2.2/105±3.7 mmHg, between the group I (antihypertensive drugs+benzodiazepines: n = 79, and the group II (antihypertensives only: n = 92. The patients taking benzodiazepines received a lower number of different antihypertensive drugs (2.3±0.09 vs. 2.7±0.10; p < 0.01, but the total antihypertensive drug load was significantly greater than in the group II (2.6±0.10 vs. 1.9±0.15 defined daily doses (DDD/patient/day; p < 0.01. Benzodiazepines were taken for anxiety (62% and hypertension (21%, rarely for insomnia, mostly once a day, at bedtime. About half the patients took benzodiazepines regularly for months or years aware of the risk for addiction. Diazepam was used by 82% of the patients. The average daily exposure to benzodiazepines was 0.45±0.05 DDD/patient/day. The drug was bought without prescription in 25% of the patients, and without consulting a physician in 12% of them. Conclusion. The study confirmed a close association of hypertension with the use of benzodiazepines. The frequent use of benzodiazepines in the patients with hypertension might be caused by an inadequate response to antihypertensive drug therapy, besides anxiety and insomnia. The therapeutic efficacy of a long-term use of low doses of benzodiazepines in hypertension requires further investigation.

  19. Benzodiazepines and risk of all cause mortality in adults: cohort study.

    Science.gov (United States)

    Patorno, Elisabetta; Glynn, Robert J; Levin, Raisa; Lee, Moa P; Huybrechts, Krista F

    2017-07-06

    Objectives  To evaluate the risk of all cause mortality associated with initiating compared with not initiating benzodiazepines in adults, and to address potential treatment barriers and confounding related to the use of a non-active comparator group. Design  Retrospective cohort study. Setting  Large de-identified US commercial healthcare database (Optum Clinformatics Datamart). Participants  1:1 high dimensional propensity score matched cohort of benzodiazepine initiators, and randomly selected benzodiazepine non-initiators with a medical visit within 14 days of the start of benzodiazepine treatment (n=1 252 988), between July 2004 and December 2013. To address treatment barriers and confounding, patients were required to have filled one or more prescriptions for any medication in the 90 days and 91-180 days before the index date (ie, the date of starting benzodiazepine treatment for initiators and the date of the selected medical visit for benzodiazepine non-initiators) and the high dimensional propensity score was estimated on the basis of more than 300 covariates. Main outcome measure  All cause mortality, determined by linkage with the Social Security Administration Death Master File. Results  Over a six month follow-up period, 5061 and 4691 deaths occurred among high dimensional propensity score matched benzodiazepine initiators versus non-initiators (9.3 v 9.4 events per 1000 person years; hazard ratio 1.00, 95% confidence interval 0.96 to 1.04). A 4% (95% confidence interval 1% to 8%) to 9% (2% to 7%) increase in mortality risk was observed associated with the start of benzodiazepine treatment for follow-ups of 12 and 48 months and in subgroups of younger patients and patients initiating short acting agents. In secondary analyses comparing 1:1 high dimensional propensity score matched patients initiating benzodiazepines with an active comparator, ie, patients starting treatment with selective serotonin reuptake inhibitor antidepressants

  20. Benzodiazepine use in general population, the municipality of Berane, Montenegro

    Directory of Open Access Journals (Sweden)

    Šoškić Miomir

    2016-01-01

    Full Text Available Background: Benzodiazepines can be classified as one of the most frequently prescribed categories of medication. This medication category is distinguished by a high risk of tolerance and dependence, in the case of long-term, excessive use. Aim: The aim of our study was to analyse the use of benzodiazepines in the general population, municipality of Berane, Montenegro, during the previous year. Methods: Research was based on the analysis of 1000 prescriptions of benzodiazepines, issued by physicians in Primary Health Care. The diagnostic manual utilised for the purpose of this research was International Classification of Diseases (ICD-10. The survey was conducted for a period of 40 days during January and February 2015. Results: The study was performed in the general population, age from 18 to 98 years (621 females and 379 males. The average age of all participants in the study was 64.1±13.1 years. Analysis of data confirmed that the most frequently prescribed from the group of benzodiazepines were: diazepam (42.2%, bromazepam (30.3%, lorazepam (16.4%, alprazolam (6.4%, nitrazepam (2.6% and clonazepam (2.1%. The significant statistical difference (x2=58.664; p<0.001 was found between female patients who used benzodiazepines in 62.1% of cases, compared to male patients who used benzodiazepines in 37.9% of cases. It was confirmed that benzodiazepines were usually prescribed for 17 different diagnoses, mostly for diagnoses from the group I, viz. cluster-diseases of the circulatory system (39.7%, group F-mental and behavioural disorders (31.1% and group E-endocrine, nutritional and metabolic diseases (7.7%. Conclusion: Studies about drug utilisation provide plenty of useful information which can be further used with the aim of achieving more rational prescribing and more effective patient treating.

  1. Chronic ethanol administration increases the binding of 3H Ro-15-4513 in primary cultured spinal cord neurons

    International Nuclear Information System (INIS)

    Mlatre, M.; Ticku, M.K.

    1989-01-01

    Ro 15-4513 (ethyl-8-azido-5, 6-dihydro-5-methyl-6-oxo-4H-imidazo [1,5α], [1,4] benzodiazepine-3-carboxylate) is reported to be a selective ethanol antagonist in biochemical and behavioral studies. The effect of chronic ethanol treatment on the binding of [ 3 H]Ro 15-4513 was investigated in cultured spinal cord neurons, which are shown to possess all the elements of GABA benzodiazepine receptor complex. Chronic ethanol treatment (50 mM for 6 hr, 12 hr, 18 hr, 3 days, and 5 3 days) produced an increase in the specific binding of [ 3 H]Ro 15-4513. The increase in binding in these neurons was due to an increase in the number (B max ) of receptor sites. This effect was specific for Ro 15-4513, since identical ethanol treatment did not alter the binding of benzodiazepine antagonist [ 3 H]Ro 15-1788 or agonist [ 3 H]flunitrazepam or inverse agonist [ 3 H]methyl-β-carboline-3-carboxylate. Similar results have been reported following chronic ethanol treatment to rats. These results suggest that the Ro 15-4513 binding sites on the oligomeric GABA receptor complex are altered following chronic ethanol administration, and support the notion of a unique role of Ro 15-4513 as an ethanol antagonist

  2. Prospective cohort study into post-disaster benzodiazepine use demonstrated only short-term increase.

    NARCIS (Netherlands)

    Dorn, T.; Yzermans, C.J.; Zee, J. van der

    2007-01-01

    OBJECTIVES: Benzodiazepines are typically prescribed for anxiety and insomnia, two complaints often reported after disasters. Benzodiazepines can cause mental or physical dependence, especially when taken for a long time. This study aims at evaluating benzodiazepine use in a disaster-stricken

  3. Nonmedical Abuse of Benzodiazepines in Opiate-Dependent Patients in Tehran, Iran

    Science.gov (United States)

    Babakhanian, Masuade; Sadeghi, Maliheh; Mansoori, Nader; Alam Mehrjerdi, Zahra; Tabatabai, Mahmood

    2012-01-01

    Objective: The purpose of the present preliminary study was to explore the prevalence of nonmedical abuse of benzodiazepines in a group of opiate-dependent patients who were on methadone maintenance treatment (MMT) program in outpatient clinics in the south-west of Tehran, Iran. Methods: 114 male and female opiate-dependent clients who met DSM.IV-TR criteria for opiate dependence with mean age 36.5 years participated in the study from 16 clinics and completed a self-report questionnaire on demographics and substance use details. Then the participants were interviewed on the details of nonmedical abuse of benzodiazepines. Results: The study findings indicated that the current nonmedical abuse of benzodiazepines was commonly prevalent among participants. The most common current benzodiazepines abused were alprazolam (100%) followed by chlordiazepoxide (96.5%), clonazepam (94.7%), diazepam (86.8%), lorazepam (79.8%) and oxazepam (73.7%) respectively. Depression (77%) and anxiety (72.8%) were frequently reported as the most important reasons associated with consuming benzodiazepines followed by problem in anger control (44.7%), suicide thought (12.3%), self-injury (7.9%), and suicide commitment (5.3%) respectively. Conclusion: Nonmedical abuse of benzodiazepines is an important problem among opiate addicts which should be considered in treatment interventions during MMT program. PMID:24644471

  4. Prolonged-release melatonin versus placebo for benzodiazepine discontinuation in patients with schizophrenia or bipolar disorder

    DEFF Research Database (Denmark)

    Baandrup, Lone; Lindschou, Jane; Winkel, Per

    2016-01-01

    OBJECTIVES: We assessed if prolonged-release melatonin can facilitate withdrawal of long-term benzodiazepine usage in patients with schizophrenia or bipolar disorder. METHODS: Randomised, placebo-controlled, blinded, parallel superiority trial of 24 weeks duration. Participants were randomised...... to prolonged-release melatonin 2 mg daily versus matching placebo and were continuously guided to gradually reduce their usual benzodiazepine dosage. The primary outcome was mean benzodiazepine daily dosage at 24 weeks. Secondary outcomes included pattern of benzodiazepine dosage over time, benzodiazepine...... cessation proportion, and benzodiazepine withdrawal symptoms. RESULTS: In total, 86 patients (21-74 years) were enrolled: 42 were randomised to melatonin versus 44 to placebo. We found no significant effect of melatonin on mean benzodiazepine dosage at 24 weeks (melatonin group 8.01 mg versus placebo group...

  5. Midazolam inhibits hippocampal long-term potentiation and learning through dual central and peripheral benzodiazepine receptor activation and neurosteroidogenesis

    OpenAIRE

    Tokuda, Kazuhiro; O’Dell, Kazuko A.; Izumi, Yukitoshi; Zorumski, Charles F.

    2010-01-01

    Benzodiazepines (BDZs) enhance γ-aminobutyric acid-A (GABAA) receptor inhibition by direct actions on central BDZ receptors (CBRs). Although some BDZs also bind mitochondrial receptors (translocator protein 18kDa, TSPO) and promote the synthesis of GABA-enhancing neurosteroids, the role of neurosteroids in the clinical effects of BDZs is unknown. In rat hippocampal slices, we compared midazolam, an anesthetic BDZ with clonazepam, an anticonvulsant/anxiolytic BDZ that activates CBRs selectivel...

  6. Qualitative variation of photolabelled benzodiazepine receptors in different species.

    Science.gov (United States)

    Hebebrand, J; Friedl, W; Lentes, K U; Propping, P

    1986-01-01

    In order to examine whether species differences of benzodiazepine receptor subunits exist, we compared the fluorographic pattern of photoaffinity labelled subunits after SDS-PAGE in five species: fish, frog, chicken, mouse and calf. Each species showed a distinct pattern of specifically labelled proteins. We conclude that species variation of benzodiazepine receptor does indeed exist.

  7. Memory impairment in those who attempted suicide by benzodiazepine overdose

    NARCIS (Netherlands)

    Verwey, B.; Eling, P.A.T.M.; Wientjes, H.J.F.M.; Zitman, F.G.

    2000-01-01

    Backgroud: a prospective study was done to investigate the presence of anterograde amnesia in suicide attempters who took benzodiazepines (BZ) and to study the correlation with sedation. Method: in 43 patients, who attempted suicide by taking benzodiazepines, memory perfomrance was tested on a

  8. Tapering off benzodiazepines in long-term users : an economic evaluation

    NARCIS (Netherlands)

    Oude Voshaar, Richard C; Krabbe, Paul F M; Gorgels, Wim J M J; Adang, Eddy M M; van Balkom, Anton J L M; van de Lisdonk, Eloy H; Zitman, Frans G

    2006-01-01

    BACKGROUND: Discontinuation of benzodiazepine usage has never been evaluated in economic terms. This study aimed to compare the relative costs and outcomes of tapering off long-term benzodiazepine use combined with group cognitive behavioural therapy (TO+CBT), tapering off alone (TOA) and usual

  9. [The efficacy of the native flumazenil for acute poisoning with benzodiazepines].

    Science.gov (United States)

    Zhu, X H; Li, J X; Wang, F

    2000-12-28

    To evaluate the efficacy of the native flumazenil for acute self-poisoning with benzodiazepines. One hundred and twenty-six patients with unconsciousness from benzodiazepines-induced self-poisoning were randomly divided into two groups: flumazenil group(Group II, 63 cases) were treated with flumazenil, and conventional-medicine group(Group I, 63 cases) with placebo(glucose, vitamin C, KCl). A modified Glasgow Coma Scale(MGCS) and Observer's Assessment of Alertness/Sedation Scale(OAA/S) were used in the assessment of consciousness. MGCS were increased by 5.3, 8.0, 9.4 and 7.3 at 15 min, 30 min, 60 min and 180 min after intravenous flumazenil(P treatment. Flumazenil might improve benzodiazepines-induced unconsciousness markedly and may be the most effective antagonist of benzodiazepines.

  10. Functional characterization of the 1,5-benzodiazepine clobazam and its major active metabolite N-desmethylclobazam at human GABA(A receptors expressed in Xenopus laevis oocytes.

    Directory of Open Access Journals (Sweden)

    Harriet Hammer

    Full Text Available The 1,5-benzodiazepine clobazam is indicated for the adjunctive treatment of seizures associated with Lennox-Gastaut syndrome in patients 2 years of age or older in the United States, and for treatment of anxiety and various forms of epilepsy elsewhere. Clobazam has been reported to exhibit different in vivo adverse effects and addiction liability profile than the classic 1,4-benzodiazepines. In this study, it was investigated whether the in vitro pharmacological properties of clobazam and its major active metabolite N-desmethylclobazam could explain some of these clinical differences. The functional properties of the two 1,5-benzodiazepines were characterized at the human γ-aminobutyric acid type A receptor (GABA(AR subtypes α1β2γ(2S, α2β2γ(2S, α3β2γ(2S, α5β2γ(2S and α6β2δ expressed in Xenopus laevis oocytes by use of two-electrode voltage-clamp electrophysiology and compared to those exhibited by the 1,4-benzodiazepine clonazepam. All three compounds potentiated GABA EC20-evoked responses through the α(1,2,3,5β2γ(2S GABA(ARs in a reversible and concentration-dependent manner, with each displaying similar EC50 values at the four subtypes. Furthermore, the degrees of potentiation of the GABA EC20 currents through the four receptors mediated by saturating modulator concentrations did not differ substantially for any of the three benzodiazepines. The three compounds were substantially less potent (200-3900 fold as positive allosteric modulators at the α6β2δ GABA(AR than at the α(1,2,3,5β2γ(2S receptors. Interestingly, however, clobazam and especially N-desmethylclobazam were highly efficacious potentiators of α6β2δ receptor signaling. Although this activity component is unlikely to contribute to the in vivo effects of clobazam/N-desmethylclobazam, the 1,5-benzodiazepine could constitute an interesting lead for novel modulators targeting this low-affinity binding site in GABAARs. In conclusion, the non

  11. Benzodiazepines, opioids and driving: an overview of the experimental research.

    Science.gov (United States)

    Leung, Stefanie Y

    2011-05-01

    Road crashes contribute significantly to the total burden of injury in Australia, with the risk of injury being associated with the presence of drugs and/or alcohol in the driver's blood. Increasingly, some of the most commonly detected drugs include prescription medicines, the most notable of these being benzodiazepines and opioids. However, there is a paucity of experimental research into the effects of prescribed psychoactive drugs on driving behaviours. This paper provides an overview of experimental studies investigating the effects of prescribed doses of benzodiazepines and opioids on driving ability, and points to future directions for research. There is growing epidemiological evidence linking the therapeutic use of benzodiazepines and opioids to an increased crash risk. However, the current experimental literature remains unclear. Limitations to study methodologies have resulted in inconsistent findings. Limited experimental evidence exists to inform policy and guidelines regarding fitness-to-drive for patients taking prescribed benzodiazepines and opioids. Further experimental research is required to elucidate the effects of these medications on driving, under varying conditions and in different medical contexts. This will ensure that doctors prescribing benzodiazepines and opioids are well informed, and can appropriately advise patients of the risks associated with driving whilst taking these medications. © 2011 Australasian Professional Society on Alcohol and other Drugs.

  12. Preliminary finding: consumption of benzodiazepines in Brazil during the years 1988 and 1989.

    Science.gov (United States)

    Nappo, S; Carlini, E A

    1993-06-01

    This work investigates consumption of benzodiazepines in Brazil during the years 1988 and 1989, using the following sources of information provided to the Brazilian Ministry of Health by institutions that deal with benzodiazepines: (a) benzodiazepine stocks recorded at the beginning and end of each year; (b) Brazilian (internal) production of benzodiazepines; (c) imported and exported amounts of benzodiazepines; (d) amounts employed in the manufacture of brand-name products and in the making of prescription formulas. The records a, b and c furnished the 'calculated consumption', of benzodiazepines, in kilograms. The d records, on the other hand, directly furnished the 'informed consumption', also in kilograms. The data obtained were also expressed in terms of defined daily doses (DDDs)/1,000 inhabitants/day, considering the informed consumption and the Brazilian population. As for the DDDs/1000 inhabitants/day, they were found to be 23.03 and 18.48 for the years 1988 and 1989, respectively. A striking discrepancy was detected between the calculated and the informed consumption figures, the latter having exceeded the former by 2096 kg in 1988 and by 4909 kg in 1989. Diazepam was the primary drug responsible for this difference. Such results may suggest that an illicit, unrecorded trade of benzodiazepines is occurring in Brazil.

  13. Benzodiazepine prescription in relation to psychiatric diagnosis and patient characteristics: A pilot study

    Directory of Open Access Journals (Sweden)

    Marić Nađa P.

    2015-01-01

    Full Text Available Introduction: Benzodiazepines are widely used drugs which are often misused. Analysis of psychotropic drugs prescription in Serbia showed high prescription rate of benzodiazepines in the psychiatric patient population, with an increasing trend. Potential association between psychiatric diagnostic categories (organic brain syndrome, psychotic disorders, bipolar disorder, unipolar depression, anxiety disorder, personality disorder, or the sociodemographic characteristics of patients (gender, age, education, marital state and benzodiazepine prescribing practice was not thoroughly tested. Aim: By analyzing routine practice of the university clinic, the aim of this study was to examine whether there is an association between clinical or socio-demographic characteristics of the patients and benzodiazepine prescribing practice. Material and methods: This study was carried out by retrospective analysis of the patient's medical charts after hospital discharge (n=102. Data analysis included descriptive statistics, testing the difference between groups and correlation analysis. Results: At the discharge, 94.1% of patients had benzodiazepines prescribed, with an average dose of 4.6 ± 3.2mg lorazepam dose equivalents. It is shown that female patients were prescribed with higher doses of benzodiazepines than male patients (p=0.018, that the average dose was higher for patients treated with an overall larger number of psychiatric drugs (p = 0.013, as well as that hospital inpatients had higher doses compared to day hospital-treated patients (p = 0.011. Patients with a diagnosis of personality disorder had a slight upward trend of benzodiazepine dose (p=0.078. Conclusion: Current research provided a clear insight into the actual practice of benzodiazepine prescription at local university center. Similarly to our region, indications for prescribing benzodiazepines appear to be quite broad and not specific enough worldwide. This is why it is important to

  14. Metabolism of anxiolytics and hypnotics: benzodiazepines, buspirone, zoplicone, and zolpidem.

    Science.gov (United States)

    Chouinard, G; Lefko-Singh, K; Teboul, E

    1999-08-01

    1. The benzodiazepines are among the most frequently prescribed of all drugs and have been used for their anxiolytic, anticonvulsant, and sedative/hypnotic properties. Since absorption rates, volumes of distribution, and elimination rates differ greatly among the benzodiazepine derivatives, each benzodiazepine has a unique plasma concentration curve. Although the time to peak plasma levels provides a rough guide, it is not equivalent to the time to clinical onset of effect. The importance of alpha and beta half-lives in the actions of benzodiazepines is discussed. 2. The role of cytochrome P450 isozymes in the metabolism of benzodiazepines and in potential pharmacokinetic interactions between the benzodiazepines and other coadministered drugs is discussed. 3. Buspirone, an anxiolytic with minimal sedative effects, undergoes extensive metabolism, with hydroxylation and dealkylation being the major pathways. Pharmacokinetic interactions of buspirone with other coadministered drugs seem to be minimal. 4. Zopiclone and zolpidem are used primarily as hypnotics. Both are extensively metabolized; N-demethylation, N-oxidation, and decarboxylation of zopiclone occur, and zolpidem undergoes oxidation of methyl groups and hydroxylation of a position on the imidazolepyridine ring system. Zopiclone has a chiral centre, and demonstrates stereoselective pharmacokinetics. Metabolic drug-drug interactions have been reported with zopiclone and erythromycin, trimipramine, and carbamazepine. Reports to date indicate minimal interactions of zolpidem with coadministered drugs; however, it has been reported to affect the Cmax and clearance of chlorpromazepine and to decrease metabolism of the antiviral agent ritonavin. Since CYP3A4 has been reported to play an important role in metabolism of zolpidem, possible interactions with drugs which are substrates and/or inhibitors of that CYP isozyme should be considered.

  15. [Can one talk of benzodiazepine "drunkenness"? About acute benzodiazepine intoxication, without suicidal or mortiferous tendencies].

    Science.gov (United States)

    Menecier, P; Texier, M A; Las, R; Ploton, L

    2012-02-01

    When we refer to "drunkenness", more often than not, we think of alcohol or cannabis being the instigator rather than pharmacological drugs, even if outside the toxic origins, "drunkenness" may also occur without any substance intake: one can be drunk on love, poetry, music and even mania. Benzodiazepine "drunkenness" is not a classical notion in medicine. But the concept of addictology allows one to enlarge different approaches and to consider the relationship with psychoactive substances according to the same references. So, in a single fashion, between use and misuse, is it possible to resort to the same concepts for pharmacological drugs, including "drunkenness"? Any intake of a psychoactive substance, limited in time, which will take the consumer some time to recover from, can be called simple use, intoxication or drunkenness. Intoxication is rather a classical medical concept linked with poisoning, and hence the toxicological aspects prevail particularly through the concept of a toxidrome. However, little research has been done on "drunkenness" in other medical aspects, neither psychological aspects nor sociological aspects. If poisoning is defined as soon as a poison is introduced into the body, the intoxication arises after a threshold (that toxicology usually defines), but no means are available to measure the onset of the inebriation, neither any ingested amounts nor any toxic concentration in the body. It is hard to define "drunkenness" simply. At first, it is most often seen as a pathology in medicine, unlike in every day life. "Drunkenness" can be the result of physiological disturbances, notably through the effects of substances and can therefore be the manifestation of a cerebral dysfunction. Alternatively, it can arise from a variation of emotional or sensorial stimuli. If the feelings associated with drunkenness are positive and pleasant a repetition will occur in the search to reproduce enjoyable effects in reference to neurophysiological models

  16. Benzodiazepine prescribing behaviour and attitudes: a survey among general practitioners practicing in northern Thailand

    Directory of Open Access Journals (Sweden)

    Critchley Julia

    2005-06-01

    Full Text Available Abstract Background Over-prescribing of benzodiazepines appears common in many countries, a better understanding of prescribing practices and attitudes may help develop strategies to reduce prescribing. This study aimed to evaluate benzodiazepine prescribing behaviour and attitudes in general practitioners practising in Chiang Mai and Lampoon, Thailand. Methods Questionnaire survey of general practitioners in community hospitals, to estimate: i use of benzodiazepines for anxiety/insomnia, panic disorder, depression, essential hypertension, and uncomplicated low back pain and ii views on the optimal duration of benzodiazepine use. Results Fifty-five of 100 general practitioners returned the completed questionnaires. They reported use of benzodiazepines for anxiety/insomnia (n = 51, 93%, panic disorder (n = 43, 78%, depression (n = 26, 43%, essential hypertension (n = 15, 27 % and uncomplicated low back pain (n = 10, 18%. Twenty-eight general practitioners would prescribe benzodiazepines for non-psychiatric conditions, 17 for use as muscle relaxants. Seventy-five per cent, 62% and 29% of the general practitioners agreed or totally agreed with the use of benzodiazepines for insomnia, anxiety and depression, respectively. Practitioners agreed that prescribing should be less than one week (80%; or from 1 week to 1 month (47%; or 1 to 4 months (16%; or 4 to 6 months (5% or more than 6 months (2%. Twenty-five general practitioners (45% accepted that they used benzodiazepines excessively in the past year. Conclusion A considerable proportion of general practitioners in Chiang Mai and Lampoon, Thailand inappropriately use benzodiazepines for physical illnesses, especially essential hypertension and uncomplicated low back pain. However, almost half of them thought that they overused benzodiazepines. General practitioner's lack of time, knowledge and skills should be taken into account in improving prescribing behaviour and attitudes.

  17. Twenty-year trends in benzodiazepine dispensing in the Australian population.

    Science.gov (United States)

    Islam, M M; Conigrave, K M; Day, C A; Nguyen, Y; Haber, P S

    2014-01-01

    Considerable concern has been expressed about overprescribing of benzodiazepines and related harms. Past analyses have relied on World Health Organization-defined daily doses (DDD) which are sometimes out of keeping with clinical usage. This study examines 20-year (1992-2011) trends of benzodiazepine dispensing in Australia using both DDD and Ashton equivalent dose. Data from the Drug Utilisation Sub-Committee and the Pharmaceutical Benefits Scheme (PBS) website were analysed. Trends in number of prescriptions, DDD/1000 people/day and DDD/prescription were examined over time, and between states/territories. In the 20-year period, 174 080 904 scripts were recorded, with temazepam the most dispensed benzodiazepine (35% of scripts), followed by diazepam (23%). Overall recorded utilisation fell from 27.7 DDD/1000 people/day in 1992 to 20.8 in 2011 (24.9% decrease). There were striking changes in use of individual benzodiazepines over time, with reductions in oxazepam and flunitrazepam and dramatic increases in alprazolam. Since 1998, there has been a steady increase, albeit modest, in per script DDD. The DDD/1000 people/day for items dispensed through PBS/Repatriaton-PBS was highest in Tasmania and lowest in Northern Territory. Despite a modest overall decline in the amount of benzodiazepine dispensed, the level of use is still likely to reflect relative over-prescribing given the paucity of accepted indications for long-term use. Since 1998, there was a polynomial increase in quantity dispensed per script. The WHO-defined DDD for clonazepam seems inappropriate and could impede monitoring of its abuse. Other problems include lack of national data for medications not subsidised on PBS/Repatriation PBS. A broad policy approach is required, not one which targets only one particular benzodiazepine. © 2013 The Authors; Internal Medicine Journal © 2013 Royal Australasian College of Physicians.

  18. Stability of solubilized benzodiazepine receptors

    NARCIS (Netherlands)

    Janssen, M.J; Ensing, K; de Zeeuw, R.A

    1997-01-01

    According to the observations of other researchers, benzodiazepine receptors solubilized with sodium deoxycholate are unstable, but stability can be improved by exchanging deoxycholate for Triton X-100. In our experiments we conclude that the choice of detergent is not the restrictive factor for the

  19. Treating acute seizures with benzodiazepines: does seizure duration matter?

    Science.gov (United States)

    Naylor, David E

    2014-10-01

    Several clinical trials have shown improved seizure control and outcome by early initiation of treatment with benzodiazepines, before arrival in the emergency department and before intravenous access can be established. Here, evidence is provided and reviewed for rapid treatment of acute seizures in order to avoid the development of benzodiazepine pharmacoresistance and the emergence of self-sustaining status epilepticus. Alterations in the physiology, pharmacology, and postsynaptic level of GABA-A receptors can develop within minutes to an hour and hinder the ability of synaptic inhibition to stop seizures while also impairing the efficacy of GABAergic agents, such as benzodiazepines, to boost impaired inhibition. In addition, heightened excitatory transmission further exacerbates the inhibitory/excitatory balance and makes seizure control even more resistant to treatment. The acute increase in the surface expression of NMDA receptors during prolonged seizures also may cause excitotoxic injury, cell death, and other pathological expressions and re-arrangements of receptor subunits that all contribute to long-term sequelae such as cognitive impairment and chronic epilepsy. In conclusion, a short window of opportunity exists when seizures are maximally controlled by first-line benzodiazepine treatment. After that, multiple pathological mechanisms quickly become engaged that make seizures increasingly more difficult to control with high risk for long-term harm.

  20. Stories of Hell and Healing: Internet Users’ Construction of Benzodiazepine Distress and Withdrawal

    OpenAIRE

    Fixsen, Alison; Ridge, Damien T.

    2017-01-01

    Abstract Benzodiazepines are a group of drugs used mainly as sedatives, hypnotics, antiepileptics, and muscle relaxants. Consumption is recommended for 2 to 4 weeks only, due to fast onset of dependency and potentially distressing withdrawal symptoms. Few peer-review studies have drawn on the user experiences and language to appreciate firsthand experiences of benzodiazepine withdrawal or discontinuation syndrome. We looked extensively at patient stories of benzodiazepine withdrawal and recov...

  1. Engagement in leisure activities and benzodiazepine use in a French community-dwelling elderly population.

    Science.gov (United States)

    Bazin, Fabienne; Noize, Pernelle; Dartigues, Jean-François; Ritchie, Karen Anne; Tavernier, Beatrice; Moore, Nicholas; Pariente, Antoine; Fourrier-Reglat, Annie

    2012-07-01

    The prevalence of benzodiazepine use among community-dwelling older persons varies between 10% and 30%. The aim of this study was to explore the association between leisure activities and the use of benzodiazepine among older persons living at home. The study population included 4848 persons aged 65 years and over living in either of two French cities. Information was collected from a questionnaire administered to the respondents by trained psychologists during face-to-face interviews at home and from a self-administered questionnaire. Baseline examination included socio-demographic characteristics, drug use and leisure activities. We classified as benzodiazepine users subjects who reported use of at least one benzodiazepine during the month preceding the interview. The association between the use of benzodiazepine and leisure activities was assessed by logistic regression adjusted on known potential confounders. More than 18% of participants reported use of at least one benzodiazepine. The adjusted odds ratio (OR) of benzodiazepine use associated with no or lower participation versus participation in the following activities were as follows: OR = 1.31 (95% confidence interval (CI): 1.09 to 1.58) for mental activity; OR = 1.50 (CI: 1.12 to 2.03) for physical activity; OR = 1.28 (CI: 1.05 to 1.55) for productive activity and OR = 0.82 (CI: 0.69 to 0.97) for recreational activity. Low engagement in stimulating activities and high engagement in sedentary activities were associated with recent benzodiazepine use. Copyright © 2011 John Wiley & Sons, Ltd.

  2. [Benzodiazepine dependence and the risk of depression and anxiety disorders: seniors' health study].

    Science.gov (United States)

    Nkogho Mengue, P-G; Abdous, B; Berbiche, D; Preville, M; Voyer, P

    2014-06-01

    The objective of this study is to examine the relationship between benzodiazepine dependence and anxiety disorders and depression in people aged 65 years and over. We referred to the data from the study on the health of seniors, a survey of a representative sample of 707 benzodiazepine users living in the community in Quebec, Canada. Benzodiazepine dependence, anxiety disorders and depression were measured using self-reported questionnaires based on the criteria of the Diagnostic and Statistical Manual of Mental Disorders, fourth revised edition. Seniors have consumed an average daily dose of 6.1±7.6mg diazepam equivalent to an average of 205±130 days. The prevalence of benzodiazepine dependence has been estimated at 9.5%. This dependence increases the risk of minor depression for females (relative risk [RR]=4.36, confidence interval 95% [95% CI]=1.19 to 15.99). The results of this study suggest that the use of benzodiazepines is far from being optimal among seniors in Quebec. The proportion of seniors who develop an addiction is important. The results illustrate the need to develop and implement programs to improve the quality of benzodiazepine use among this population. Copyright © 2013 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

  3. Benzodiazepine Use Among Low Back Pain Patients Concurrently Prescribed Opioids in the Military Health System

    Science.gov (United States)

    2017-08-27

    TYPE 08/27/2017 Poster 4. TITLE AND SUBTITLE Benzodiazepine Lise Among Lo\\v Back Pain Patients Concurrently Prescribed Opioids in the tvfilitary...PRO’-:iRAM ELEMENT NUMBER 5d. PROJECT NUMBER Se. TASK NUMBER Sf. WORK UNIT NUMBER 8. PERFORMING ORGANIZATION REPORT NUMBER 17356 10. SPONSOR

  4. Benzodiazepines and risk for hepatic encephalopathy in patients with cirrhosis and ascites

    DEFF Research Database (Denmark)

    Grønbæk, Lisbet; Watson, Hugh; Vilstrup, Hendrik

    2018-01-01

    Background: There is limited evidence to support the belief that benzodiazepines increase cirrhosis patients’ risk of hepatic encephalopathy (HE). Objective: We aimed to examine the association between benzodiazepine use and HE development in cirrhosis patients. Methods: We used data on 865...

  5. Iodine-125 radioimmunoassay for the direct detection of benzodiazepines in blood and urine

    Energy Technology Data Exchange (ETDEWEB)

    Goddard, C.P.; Stead, A.H.; Mason, P.A.; Law, B.; Moffat, A.C.; McBrien, M.; Cosby, S.

    1986-05-01

    A radioimmunoassay (RIA) for the direct detection of benzodiazepines in blood and urine is described. It is based on a commercially available antiserum and an easily synthesised radio-iodinated derivative of clonazepam that allows the use of relatively simple gamma-counting procedures. The assay can detect low therapeutic levels of all of the benzodiazepines currently available in the UK in 50-..mu..l samples of blood and urine (1-50 ng ml/sup -1/, depending on the drug); no prior sample preparation is required. It is inexpensive, rapid, simple to perform and is broadly specific for the benzodiazepine class of drugs. The assay offers a most suitable means of screening large numbers of samples of forensic interest for the presence of the benzodiazepines.

  6. High enhancer, downer, withdrawal helper: Multifunctional nonmedical benzodiazepine use among young adult opioid users in New York City.

    Science.gov (United States)

    Mateu-Gelabert, Pedro; Jessell, Lauren; Goodbody, Elizabeth; Kim, Dongah; Gile, Krista; Teubl, Jennifer; Syckes, Cassandra; Ruggles, Kelly; Lazar, Jeffrey; Friedman, Sam; Guarino, Honoria

    2017-08-01

    Benzodiazepines are a widely prescribed psychoactive drug; in the U.S., both medical and nonmedical use of benzodiazepines has increased markedly in the past 15 years. Long-term use can lead to tolerance and dependence, and abrupt withdrawal can cause seizures or other life-threatening symptoms. Benzodiazepines are often used nonmedically in conjunction with other drugs, and with opioids in particular-a combination that can increase the risk for fatal and non-fatal overdose. This mixed-methods study examines nonmedical use of benzodiazepines among young adults in New York City and its relationship with opioid use. For qualitative analysis, 46 90-minute semi-structured interviews were conducted with young adult opioid users (ages 18-32). Interviews were transcribed and coded for key themes. For quantitative analysis, 464 young adult opioid users (ages 18-29) were recruited using Respondent-Driven Sampling and completed structured interviews. Benzodiazepine use was assessed via a self-report questionnaire that included measures related to nonmedical benzodiazepine and opioid use. Participants reported using benzodiazepines nonmedically for a wide variety of reasons, including: to increase the high of other drugs; to lessen withdrawal symptoms; and to come down from other drugs. Benzodiazepines were described as readily available and cheap. There was a high prevalence (93%) of nonmedical benzodiazepine use among nonmedical opioid users, with 57% reporting regular nonmedical use. In bivariate analyses, drug-related risk behaviours such as polysubstance use, drug binging, heroin injection and overdose were strongly associated with regular nonmedical benzodiazepine use. In multivariate analysis, growing up in a middle-income household (earning between $51,000 and $100,000 annually), lifetime overdose experience, having ever used cocaine regularly, having ever been prescribed benzodiazepines, recent drug binging, and encouraging fellow drug users to use benzodiazepines to

  7. Addressing the Issue of Chronic, Inappropriate Benzodiazepine Use: How Can Pharmacists Play a Role?

    Directory of Open Access Journals (Sweden)

    Helen C. Gallagher

    2013-09-01

    Full Text Available Prescribing guidelines do not recommend the long-term use of benzodiazepines since their effectiveness with chronic use is out-weighed by risks including dependence, memory and cognitive impairment, hip fractures and traffic accidents. Despite these guidelines, historical data points to an increasing proportion of inappropriate, repeat prescribing of benzodiazepines in Ireland and elsewhere, with up to 33% of patients who use these drugs doing so long-term. The typical long-term benzodiazepine user is an older, socio-economically disadvantaged patient who has been prescribed these medicines by their general practitioner (GP and dispensed them by their community pharmacist. Misuse of benzodiazepines in nursing homes and psychiatric institutions is also of concern, with one Irish study indicating that almost half of all admissions to a psychiatric hospital were prescribed these drugs, usually despite a lack of clear clinical need. Discontinuation of benzodiazepines has proven to be of benefit, as it is followed by improvements in cognitive and psychomotor function, particularly in elderly patients. It is obvious that an inter-professional effort, focusing on the primary care setting, is required to address benzodiazepine misuse and to ensure appropriate pharmaceutical care. Pharmacists must be an integral part of this inter-professional effort, not least because they are uniquely positioned as the health professional with most frequent patient contact. There is already some supporting evidence that pharmacists’ involvement in interventions to reduce benzodiazepine use can have positive effects on patient outcomes. Here, this evidence is reviewed and the potential for pharmacists to play an expanded role in ensuring the appropriate use of benzodiazepines is discussed.

  8. Differences in health status between long-term and short-term benzodiazepine users.

    NARCIS (Netherlands)

    Zandstra, S.M.; Furer, J.W.; Lisdonk, E.H. van de; Bor, J.H.J.; Zitman, F.G.; Weel, C. van

    2002-01-01

    BACKGROUND: Despite generally accepted advice to keep treatment short, benzodiazepines are often prescibed for more than six months. Prevention of long-term benzodiazepine use could be facilitated by the utilisation of risk indicators for long-term use. However, the characteristics of long-term

  9. Benzodiazepines: minder gebruiken is beter gebruiken

    NARCIS (Netherlands)

    Oei, T.T.; Loonen, A.J.M.

    1981-01-01

    The benzodiazepines take an important place in the treatment of anxiety and sleep-disorders. The pharmacokinetic, pharmacodynamic and therapeutic properties of these drugs are shortly dealt with, whereafter the development of tolerance and dependence is considered in more detail. The clinical

  10. New benzodiazepine and Z-hypnotic users and disability pension: an eight-year nationwide observational follow-up study.

    Science.gov (United States)

    Tvete, Ingunn F; Bjørner, Trine; Skomedal, Tor

    2017-09-01

    To compare how newly initiated treatment with benzodiazepines, Z-hypnotics or both associates with the reception of disability pension among 40,661 individuals of a working age. Prescription register study. Norwegian nationwide prescriptions socio-economic and disability status data. Cox regression analyses. New benzodiazepine or Z-hypnotic users. Time to receive disability pension given benzodiazepine or Z-hypnotic use or both. Additional analyses focused on the benzodiazepine first redeemed. Among new users 8.65% of Z-hypnotic users, 12.29% of benzodiazepines users and 13.96% of combined Z-hypnotic and benzodiazepine users became disability pensioners. Z-hypnotic users were weaker associated with becoming disability pensioners (HR = 0.78, CI: 0.73-0.84) and combined users were stronger associated (HR = 1.09, CI: 1.01-1.17), than benzodiazepine users. Women had higher risk than men for becoming disability pensioners. Higher age, lower education, previous drug use and psychiatrist as first prescriber were risk factors. Comparing first benzodiazepine redeemed; clonazepam initiators were stronger associated with becoming disability pensioners than diazepam initiators were (HR = 2.22, CI: 1.81-2.71). No differences between other benzodiazepine users were found. Adjusting for known risk factors gave lower risk for Z-hypnotic users compared to benzodiazepine users for receiving disability pension. Combined use increased the risk further. Clonazepam initiators are especially at risk. These findings may be helpful in prescribing situations to identify and guide individuals at risk for becoming disability pensioners.

  11. No role for benzodiazepines in posttraumatic stress disorder? A surplus of certainty despite scarce evidence.

    Science.gov (United States)

    Starcevic, Vladan

    2017-08-01

    This article addresses some of the controversies about the role of benzodiazepines in the treatment of posttraumatic stress disorder. Benzodiazepines have been admonished in treatment guidelines for posttraumatic stress disorder, but this is based on very little solid evidence. Although benzodiazepines do not seem to be effective in the treatment of the core posttraumatic stress disorder symptoms, their careful use as adjunctive agents for the symptoms such as anxiety and sleep disturbance may be useful. Future research needs to identify predictors of improved treatment outcomes in posttraumatic stress disorder with use of benzodiazepines.

  12. Radioreceptor assay for benzodiazepines in biological fluids using a new dry and stable receptor preparation

    International Nuclear Information System (INIS)

    Lund, J.

    1981-01-01

    A method for determination of benzodiazepines in human blood, plasma, saliva and urine has been developed. The method is based upon the competition between 3 H-flunitrazepam and biologically active benzodiazepines in biological fluids for brain specific receptors, prepared in a stable, dry form and easy to handle. The pharmacological specificity for benzodiazepines of the dry stable receptor preparation is closely similar to that of fresh membrane-bound rat brain receptors. The method is specific for biologically active benzodiazepines; it is relatively rapid, sensitive and reproducible, and can be performed at room temperature. (author)

  13. The association between benzodiazepine use and sleep quality in residential aged care facilities: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Lynna Chen

    2016-11-01

    Full Text Available Abstract Background Benzodiazepines are commonly prescribed in residential aged care facilities (RACFs for their sedative and anxiolytic effects. The objective of this study was to investigate the association between benzodiazepine use and sleep quality in residents of RACFs. Methods A cross-sectional study involving 383 participants was conducted in six Australian RACFs. Night-time sleep quality, day-time drowsiness and day-time napping behavior were assessed using a validated questionnaire. Logistic regression was used to compute adjusted odds ratios (AORs and 95% confidence intervals (CIs for the association between benzodiazepine use and sleep quality. Covariates included pain, dementia severity, depression, insomnia and other sedative use. Results Of the 383 residents (mean age 87.5 years, 77.5% female, 96(25.1% used a benzodiazepine on a regular basis. Residents who used long-acting benzodiazepines on a regular basis had higher night-time sleep quality than non-users (AOR = 4.00, 95%CI 1.06 – 15.15. Residents who used short-acting benzodiazepines on a PRN only basis had longer daytime napping times than non-users (AOR = 1.77, 95%CI 1.01 – 3.08. No benzodiazepine category was associated with day-time drowsiness. Conclusions The association between benzodiazepine use and sleep quality is dependent on the half-life and prescribing pattern of the benzodiazepine. Short-acting PRN benzodiazepines were associated with lower night time sleep quality and longer day-time napping compared to long-acting regular benzodiazepines. Longitudinal studies are needed to determine whether these findings reflect channeling of short-acting agents to residents at higher risk of sleep disorders.

  14. Disability pension as predictor of later use of benzodiazepines among benzodiazepine users

    OpenAIRE

    Hartz, Ingeborg; Tverdal, Aage; Skille, Eivind Å.; Skurtveit, Svetlana

    2010-01-01

    The original publication is available at: http://dx.doi.org/10.1016/j.socscimed.2009.11.015 The proportion of Norwegians on disability pensions has doubled since the 1980s. The Norwegian Government wants action to stimulate the working capacity in those disability pensioners who have the potential to work. Information on factors that may impair rehabilitation efforts, including the unfavourable use of benzodiazepines, may be useful in this context. A longitudinal design, including data on ...

  15. Epidemic Use of Benzodiazepines among Older Adults in Israel: Epidemiology and Leverage Points for Improvement.

    Science.gov (United States)

    Steinman, Michael A; Low, Marcelo; Balicer, Ran D; Shadmi, Efrat

    2017-08-01

    Benzodiazepines and benzodiazepine-receptor agonists (BDZRAs, often known as "Z-drugs") are commonly used in older adults despite well-documented harms. To evaluate patterns of benzodiazepine and BDZRA use in Israel, focusing on potential leverage points where quality improvement initiatives might effectively curtail new use or the transition from intermittent to chronic use. We used national electronic medical data to assess a 10% random sample of adults receiving care in Clalit Health Services, which serves half of Israel's population. The sample included 267,221 adults, of whom 56,808 (21%) were age 65 and older. Medication use from 2013 to 2015 was ascertained using pharmacy dispensing data. In 2014, 7% of adults age 21-64 and 32% of adults age 65 and older received at least one benzodiazepine/BDZRA, including 49% of adults age 85 and older (P older users (59%) were long-term users of the drugs, and 21% of older adults who were short-term users in 2014 transitioned to medium- or long-term use in 2015. Older Arab Israelis were much less likely to receive benzodiazepine/BDZRAs than older Jewish Israelis (adjusted OR 0.28, 95% 0.25-0.31), but within each community there was no major variation in prescribing rates across clinics. Depression diagnosis was associated with particularly high rates of benzodiazepine/BDZRA use: 17% of older adults with depression received a benzodiazepine/BDZRA but no antidepressant, and 42% received both. Recent hospitalization increased the risk of new benzodiazepine/BDZRA use (adjusted OR 1.41, 95% CI 1.01-1.96), but the absolute risk increase was only 3%. Benzodiazepines/BDZRAs are used at exceptionally high rates by older Israeli adults, especially the oldest old. Important leverage points for quality improvement efforts include curtailing the transition from short-term to long-term use, reducing use in older adults with depression, and identifying reasons that explain large differences in benzodiazepine/BDZRA prescribing between

  16. A 5-year follow-up study of users of benzodiazepine: starting with diazepam versus oxazepam.

    Science.gov (United States)

    Tvete, Ingunn Fride; Bjørner, Trine; Skomedal, Tor

    2016-04-01

    Drug dependency may develop during long-term benzodiazepine use, indicated, for example, by dose escalation. The first benzodiazepine chosen may affect the risk of dose escalation. To detect possible differences in benzodiazepine use between new users of diazepam and oxazepam over time. This 5-year prescription database study included 19 747 new benzodiazepine users, inhabitants of Norway, aged 30-60 years, with first redemption for diazepam or oxazepam. Individuals starting on diazepam versus oxazepam were analysed by logistic regression with sex, age, other drug redemptions, prescriber's specialty, household income, education level, type of work, and vocational rehabilitation support as background variables. Time to reach a daily average intake of ≥1 defined daily doses (DDD) over a 3-month period was analysed using a Cox proportional hazard regression model. New users of oxazepam had a higher risk for dose escalation compared with new users of diazepam. This was true even when accounting for differences in sociodemographic status and previous drug use (hazard ratio [HR] 1.33, 95% confidence interval = 1.17 to 1.51). Most doctors prescribed, according to recommendations, oxazepam to individuals they may have regarded as prone to and at risk of dependency. However, these individuals were at higher risk for dose escalation even when accounting for differences in sociodemographic status and previous drug use. Differences between the two user groups could be explained by different preferences for starting drug, DDD for oxazepam being possibly too low, and some unaccounted differences in illness. © British Journal of General Practice 2016.

  17. The labelling of 2-oxoquazepam with electrophilic 18F

    International Nuclear Information System (INIS)

    Duelfer, T.; Johnstroem, P.; Stone-Elander, S.

    1991-01-01

    2-Oxoquazepam, 7-chloro-1-(2,2,2-trifluoroethyl)-1,3-dihydro-5-(2-fluorophenyl)-2H-1,4-benzo-diazepine-2-one, is a benzodiazepine agonist. It has been shown to bind in vitro with a higher affinity to benzodiazepine type 1 receptors than to type 2 receptors. Here we report the synthesis of a trimethylin precursor and demonstrate the feasibility of using it for radiolabelling acid- and base-sensitive benzodiazepine structures such as 2-oxoquazepam. Conversions of the electrophilic fluorine to [ 18 F]-2-oxoquazepam on the order 20-25% were obtained. (author)

  18. Le benzodiazepine nel trattamento dell’ansia: profilo clinico e farmacoeconomico

    Directory of Open Access Journals (Sweden)

    Barbara Cascio

    2005-12-01

    Full Text Available Anxiety disorders impose a significant economic burden on healthcare system, patients and society as a whole. A patient with anxiety disorders, especially with panic disorder, shows some difficulties to work or to maintain an acceptable social functioning, and, frequently, needs more medical care than a normal subject, often due to unnecessary or inappropriate diagnostic tests. Adequate psychiatric treatment of anxiety disorders can lead to higher direct specialists costs (psychiatric drugs and visits but this may be offset by a decrease in non-specialist care costs and in indirect costs. Benzodiazepines have been extensively used for the treatment of anxiety and related disorders since the 1960s. Although new pharmacological and psychological treatments for anxiety are available, a lot of psychiatrists continue to endorse benzodiazepines as primary or adjunctive treatment for these disturbs, especially in the early or acute phases of the illness. In Italy, benzodiazepines have been available also as generic drugs for some years. In order to be accepted for marketing, a generic drug has to demonstrate bioequivalence, considered a reliable proxy of therapeutic equivalence, with the standard formulation and its price has to be at least 20% cheaper than the originator drug. The use of generic drugs can contain drug expenditures and facilitate a competitive market. Despite that their prices are considerably higher than those of generics, branded benzodiazepines are still widely prescribed, because of prejudices and lack of information in the community of physicians and patients. In conclusion, benzodiazepines may treat anxiety disorders, mainly in early and acute phases, increasing quality of life and saving medical resources. The availability of generics allows for marginal reduction in initial investment in drug costs.

  19. Risk of pneumonia associated with incident benzodiazepine use among community-dwelling adults with Alzheimer disease.

    Science.gov (United States)

    Taipale, Heidi; Tolppanen, Anna-Maija; Koponen, Marjaana; Tanskanen, Antti; Lavikainen, Piia; Sund, Reijo; Tiihonen, Jari; Hartikainen, Sirpa

    2017-04-10

    Knowledge regarding whether benzodiazepines and similarly acting non-benzodiazepines (Z-drugs) are associated with an increased risk of pneumonia among older adults is lacking. We sought to investigate this association among community-dwelling adults with Alzheimer disease, a condition in which both sedative/hypnotic use and pneumonia are common. We obtained data on all community-dwelling adults with a recent diagnosis of Alzheimer disease in Finland (2005-2011) from the Medication use and Alzheimer disease (MEDALZ) cohort, which incorporates national registry data on prescriptions, reimbursement, hospital discharges and causes of death. Incident users of benzodiazepines and Z-drugs were identified using a 1-year washout period and matched with nonusers using propensity scores. The association with hospital admission or death due to pneumonia was analyzed with the Cox proportional hazards model and adjusted for use of other psychotropic drugs in a time-dependent manner. Among 49 484 eligible participants with Alzheimer disease, 5232 taking benzodiazepines and 3269 taking Z-drugs were matched 1:1 with those not taking these drugs. Collectively, use of benzodiazepines and Z-drugs was associated with an increased risk of pneumonia (adjusted hazard ratio [HR] 1.22, 95% confidence interval [CI] 1.05-1.42). When analyzed separately, benzodiazepine use was significantly associated with an increased risk of pneumonia (adjusted HR 1.28, 95% CI 1.07-1.54), whereas Z-drug use was not (adjusted HR 1.10, 95% CI 0.84-1.44). The risk of pneumonia was greatest within the first 30 days of benzodiazepine use (HR 2.09, 95% CI 1.26-3.48). Benzodiazepine use was associated with an increased risk of pneumonia among patients with Alzheimer disease. Risk of pneumonia should be considered when weighing the benefits and risks of benzodiazepines in this population. © 2017 Canadian Medical Association or its licensors.

  20. Synthesis of a Benzodiazepine-derived Rhodium NHC Complex by C-H Bond Activation

    Energy Technology Data Exchange (ETDEWEB)

    Bergman, Roberg G.; Gribble, Jr., Michael W.; Ellman, Jonathan A.

    2008-01-30

    The synthesis and characterization of a Rh(I)-NHC complex generated by C-H activation of 1,4-benzodiazepine heterocycle are reported. This complex constitutes a rare example of a carbene tautomer of a 1,4-benzodiazepine aldimine stabilized by transition metal coordination and demonstrates the ability of the catalytically relevant RhCl(PCy{sub 3}){sub 2} fragment to induce NHC-forming tautomerization of heterocycles possessing a single carbene-stabilizing heteroatom. Implications for the synthesis of benzodiazepines and related pharmacophores via C-H functionalization are discussed.

  1. Status epilepticus: Role for etiology in determining response to benzodiazepines.

    Science.gov (United States)

    Joshi, Suchitra; Rajasekaran, Karthik; Hawk, Kyle M; Chester, Stephen J; Goodkin, Howard P

    2018-04-01

    Clinical factors contributing to benzodiazepine failure in treating status epilepticus (SE) include suboptimal dosing and seizure duration. As many benzodiazepine-refractory episodes of SE arise from acute etiologies, we sought to determine whether etiology impacts SE treatment. The potency of diazepam to terminate SE induced by lithium-pilocarpine (LiPilo-SE) or kainic acid (KA-SE) in 3-week-old rats was studied by video-electroencephalography. Synaptic γ-aminobutyric acid type A receptor (GABAR)-mediated currents were recorded from dentate granule cells using voltage-clamp electrophysiology. Surface expression of γ2 subunit-containing GABARs and Kv4.2 potassium channels in hippocampal slices was determined using a biotinylation assay. Expression of phosphorylated forms of β2/3 and γ2 subunits was determined using phosphospecific antibodies and Western blotting. Diazepam failed to terminate late SE in LiPilo-SE animals but was successful in terminating KA-SE of 1- and 3-hour duration. One hour after SE onset, GABAR-mediated synaptic inhibition and γ2 subunit-containing GABAR surface expression were reduced in LiPilo-SE animals. These were unchanged in KA-SE animals at 1 and 3 hours. Phosphorylation of γ2 subunit residue S327 was unchanged in both models, although GABAR β3 subunit S408/409 residues were dephosphorylated in the LiPilo-SE animals. Kv4.2 potassium channel surface expression was increased in LiPilo-SE animals but reduced in KA-SE animals. SE-model-dependent differences support a novel hypothesis that the development of benzodiazepine pharmacoresistance may be etiologically predetermined. Further studies are required to investigate the mechanisms that underlie such etiological differences during SE and whether etiology-dependent protocols for the treatment of SE need to be developed. Ann Neurol 2018;83:830-841. © 2018 American Neurological Association.

  2. Specialty training and the personal use of benzodiazepines by physicians affect their proneness to prescribe tranquilizers.

    Science.gov (United States)

    Linden, M; Gothe, H

    1998-03-01

    The decision on how to treat a patient does not depend on clinical matters or illness characteristics alone, but also on patient, physician and setting variables such as personality, training, or reimbursement. No research has yet been carried out to answer the question whether personal experience with medications also influences prescribing behavior. In this study, 124 physicians stratified according to specialty (neuropsychiatrists vs. general practitioners), type of institution (private practice vs. hospital), years of professional experience (young vs. old), and region (rural vs. urban) participated in a structured interview to evaluate their proneness to prescribe benzodiazepines for sleep disorders as well as their personal experience in taking benzodiazepines for their own sleep problems. Both specialty and personal experience were significantly related to proneness to prescribe. Other variables tested (region, institution, age, gender) did not help to explain the variance in benzodiazepine prescribing practice. Thus physician variables and, importantly, their own personal experience in taking the medication significantly influence treatment choice. Rational medical decision making and treatment guidelines must therefore take into account medical knowledge as well as knowledge of personal treatment preferences and professional biases.

  3. [Impact of benzodiazepine dependence on the use of health services: study of the health of seniors].

    Science.gov (United States)

    Nkogho Mengue, Pamphile-Gervais; Abdous, Belkacem; Berbiche, Djamal; Préville, Michel; Voyer, Philippe

    2013-03-01

    The use of benzodiazepines is common among seniors. This consumption can cause an addiction whose criteria in the Diagnostic and Statistical Manual of Mental Disorders, 4th edition revised (DSM-IV-TR) do not always apply to the situation of the elderly. This research seeks to examine the link between the feeling of benzodiazepine dependence and the use of health services by seniors. A secondary objective is to describe the use of benzodiazepines among seniors living in the community. Data derive from a survey conducted in Quebec in 2005-2006 from a representative sample of 707 Francophones aged 65 and over living in the community. The feeling of benzodiazepine dependence was measured by a composite variable incorporating two questions inspired by the DSM-IV-TR. The use of health services was measured through the cumulative impact of consultation with health care professionals during a 12- month period. Older adults consumed a total of 745 benzodiazepines, including 117 (16.5%) which had a half-long life. The proportion of seniors who reported a feeling of dependence on benzodiazepines was estimated at 35.1 %. These seniors did not significantly make further use of health services for their addiction to benzodiazepines. The results of this study suggest that the use of benzodiazepines among seniors in Quebec is far from optimal. Moreover, the perceived need in addiction is not a significant factor in inducing seniors to use health services for the management of addiction. There is, therefore, a need for research to better understand the barriers associated with the use of health services by seniors addicted to benzodiazepines.

  4. Circadian rest-activity rhythms during benzodiazepine tapering covered by melatonin versus placebo add-on

    DEFF Research Database (Denmark)

    Baandrup, Lone; Fasmer, Ole Bernt; Glenthøj, Birte Yding

    2016-01-01

    is associated with changes in circadian rhythm parameters. METHOD: Data were derived from a randomized, double-blinded clinical trial with 24 weeks follow-up. Participants were randomized to add-on treatment with prolonged-release melatonin (2 mg) or matching placebo, and usual benzodiazepine dosage...... significantly increased the interdaily stability and at a trend level decreased the intradaily variability compared with placebo. Benzodiazepine dose reduction was not associated with these circadian rhythm parameters. Activity counts were generally higher after benzodiazepine dose reduction compared with pre......BACKGROUND: Patients with severe mental illness often suffer from disruptions in circadian rest-activity cycles, which might partly be attributed to ongoing psychopharmacological medication. Benzodiazepines are frequently prescribed for prolonged periods despite recommendations of only short...

  5. An iodine-125 radioimmunoassay for the direct detection of benzodiazepines in blood and urine

    International Nuclear Information System (INIS)

    Goddard, C.P.; Stead, A.H.; Mason, P.A.; Law, B.; Moffat, A.C.; McBrien, M.; Cosby, S.

    1986-01-01

    A radioimmunoassay (RIA) for the direct detection of benzodiazepines in blood and urine is described. It is based on a commercially available antiserum and an easily synthesised radio-iodinated derivative of clonazepam that allows the use of relatively simple gamma-counting procedures. The assay can detect low therapeutic levels of all of the benzodiazepines currently available in the UK in 50-μl samples of blood and urine (1-50 ng ml -1 , depending on the drug); no prior sample preparation is required. It is inexpensive, rapid, simple to perform and is broadly specific for the benzodiazepine class of drugs. The assay offers a most suitable means of screening large numbers of samples of forensic interest for the presence of the benzodiazepines. (author)

  6. Biodistribution, binding specificity and metabolism of [{sup 18}F]fluoroethylflumazenil in rodents

    Energy Technology Data Exchange (ETDEWEB)

    Leveque, Philippe; Labar, Daniel; Gallez, Bernard E-mail: gallez@cmfa.ucl.ac.be

    2001-10-01

    Pre-clinical studies were carried out in order to characterize in rodents the biodistribution, the binding specificity and the metabolism of [{sup 18}F]Fluoroethylflumazenil ([{sup 18}F]FEF), a potential candidate for in vivo imaging of the benzodiazepine receptors. In vivo competition with flumazenil indicates that [{sup 18}F]FEF binds specifically to the benzodiazepine receptor in the brain. The accumulation of [{sup 18}F]FEF was significantly lower than using [{sup 3}H]Flumazenil. The rather low accumulation in the brain is due to a rapid metabolism of [{sup 18}F]FEF in hydrophylic metabolites which cannot cross the blood brain barrier, and are rapidly eliminated in the urine. Inhibition of the metabolism by acetaminophen (chemically induced hepatitis) led to a significant increase of the radioactivity found in the circulating blood and in the brain, while these results were not observed using classical inhibitors of the cytochrome CYP450, cimetidine and ketoconazole.

  7. The relation between the blood benzodiazepine concentration and performance in suspected impaired drivers

    NARCIS (Netherlands)

    Smink, B.E.; Lusthof, K.J.; de Gier, J.J.; Uges, D.R.; Egberts, A.C.

    2008-01-01

    Several experimental studies have shown a negative influence of benzodiazepines on driving skills. The objective of this study is to study the relationship between the blood concentration of benzodiazepines and the influence on performance in field sobriety tests. A retrospective case file

  8. Benzodiazepine Synthesis and Rapid Toxicity Assay

    Science.gov (United States)

    Fletcher, James T.; Boriraj, Grit

    2010-01-01

    A second-year organic chemistry laboratory experiment to introduce students to general concepts of medicinal chemistry is described. Within a single three-hour time window, students experience the synthesis of a biologically active small molecule and the assaying of its biological toxicity. Benzodiazepine rings are commonly found in antidepressant…

  9. Takotsubo Cardiomyopathy and Catatonia in the Setting of Benzodiazepine Withdrawal

    Directory of Open Access Journals (Sweden)

    Teng J. Peng

    2016-01-01

    Full Text Available We report two serious and unusual complications of benzodiazepine withdrawal in a single patient: takotsubo cardiomyopathy and catatonia. This 61-year-old female patient was brought to the emergency department with lethargy and within hours had declined into a state of catatonia. Although there was never a complaint of chest pain, ECG showed deep anterior T-wave inversions and cardiac enzymes were elevated. An echocardiogram was consistent with takotsubo cardiomyopathy. She later received 1 mg of midazolam and within minutes had resolution of catatonic symptoms. Careful history revealed that she had omitted her daily dose of lorazepam for 3 days prior to admission. To our knowledge, the case presented herein is the first report of simultaneous catatonia and takotsubo cardiomyopathy in the setting of benzodiazepine withdrawal. The pathogenesis of both conditions is poorly understood but may be indirectly related to the sudden decrease in γ-aminobutyric acid (GABA signaling during benzodiazepine withdrawal.

  10. CYP2C9 Genotypes Modify Benzodiazepine-Related Fall Risk: Original Results From Three Studies With Meta-Analysis.

    Science.gov (United States)

    Ham, Annelies C; Ziere, Gijsbertus; Broer, Linda; Swart, Karin M A; Enneman, Anke W; van Dijk, Suzanne C; van Wijngaarden, Janneke P; van der Zwaluw, Nikita L; Brouwer-Brolsma, Elske M; Dhonukshe-Rutten, Rosalie A M; van Schoor, Natasja M; Zillikens, M Carola; van Gelder, Teun; de Vries, Oscar J; Lips, Paul; Deeg, Dorly J H; de Groot, Lisette C P G M; Hofman, Albert; Witkamp, Renger F; Uitterlinden, André G; Stricker, Bruno H; van der Velde, Nathalie

    2017-01-01

    To investigate whether the CYP2C9*2 and *3 variants modify benzodiazepine-related fall risk. Three prospective studies; the Rotterdam Study, B-PROOF, and LASA. Community-dwelling individuals living in or near five Dutch cities. There were 11,485 participants aged ≥55 years. Fall incidents were recorded prospectively. Benzodiazepine use was determined using pharmacy dispensing records or interviews. Cox proportional hazard models adjusted for age and sex were applied to determine the association between benzodiazepine use and fall risk stratified for CYP2C9 genotype and comparing benzodiazepine users to nonusers. The results of the three studies were combined applying meta-analysis. Within benzodiazepine users, the association between genotypes and fall risk was also assessed. Three thousand seven hundred five participants (32%) encountered a fall during 91,996 follow-up years, and 4% to 15% (depending on the study population) used benzodiazepines. CYP2C9 variants had frequencies of 13% for the *2 allele and 6% for the *3 allele. Compared to nonusers, current benzodiazepine use was associated with an 18% to 36% increased fall risk across studies with a combined hazard ratio (HR) = 1.26 (95% confidence interval [CI], 1.13; 1.40). CYP2C9*2 or *3 allele variants modified benzodiazepine-related fall risk. Compared to nonusers, those carrying a CYP2C9*2 or *3 allele and using benzodiazepines had a 45% increased fall risk (HR, 1.45 95% CI, 1.21; 1.73), whereas CYP2C9*1 homozygotes using benzodiazepines had no increased fall risk (HR, 1.14; 95% CI, 0.90; 1.45). Within benzodiazepine users, having a CYP2C9*2 or *3 allele was associated with an increased fall risk (HR, 1.35; 95% CI, 1.06; 1.72). Additionally, we observed an allele dose effect; heterozygous allele carriers had a fall risk of (HR = 1.30; 95% CI, 1.05; 1.61), and homozygous allele carriers of (HR = 1.91 95% CI, 1.23; 2.96). CYP2C9*2 and *3 allele variants modify benzodiazepine-related fall risk. Those

  11. Effect of chronic (-)-nicotine treatment on rat cerebral benzodiazepine receptors

    International Nuclear Information System (INIS)

    Magata, Yasuhiro; Kitano, Haruhiro; Shiozaki, Toshiki; Iida, Yasuhiko; Nishizawa, Sadahiko; Saji, Hideo; Konishi, Junji

    2000-01-01

    The purpose of this study was to clarify the effect of (-)-nicotine on cerebral benzodiazepine receptors (BzR) with radiotracer methods. The effect of (-)-nicotine on BzR was examined in in vitro studies using chronic (-)-nicotine-treated rats using 3 H-diazepam. The in vitro radioreceptor assay showed a 14% increase in the maximum number of binding sites of BzR in chronic (-)-nicotine-treated rats in comparison with the control rats. Moreover, a convenient in vivo uptake index of 125 I-iomazenil was calculated and a higher uptake of the radioactivity was observed in the chronic (-)-nicotine-treated group than in the control group. Although further studies of the mechanism of (-)-nicotine on such BzR changes are required, an increase in the amount of BzR in the cerebral cortex was found in rats that underwent chronic (-)-nicotine treatment, and this result contributed to the understanding of the effects of (-)-nicotine and smoking on neural functions

  12. Identification of carbohydrate-binding domains in the attachment proteins of type 1 and type 3 reoviruses.

    Science.gov (United States)

    Chappell, J D; Duong, J L; Wright, B W; Dermody, T S

    2000-09-01

    The reovirus attachment protein, sigma1, is responsible for strain-specific patterns of viral tropism in the murine central nervous system and receptor binding on cultured cells. The sigma1 protein consists of a fibrous tail domain proximal to the virion surface and a virion-distal globular head domain. To better understand mechanisms of reovirus attachment to cells, we conducted studies to identify the region of sigma1 that binds cell surface carbohydrate. Chimeric and truncated sigma1 proteins derived from prototype reovirus strains type 1 Lang (T1L) and type 3 Dearing (T3D) were expressed in insect cells by using a baculovirus vector. Assessment of expressed protein susceptibility to proteolytic cleavage, binding to anti-sigma1 antibodies, and oligomerization indicates that the chimeric and truncated sigma1 proteins are properly folded. To assess carbohydrate binding, recombinant sigma1 proteins were tested for the capacity to agglutinate mammalian erythrocytes and to bind sialic acid presented on glycophorin, the cell surface molecule bound by type 3 reovirus on human erythrocytes. Using a panel of two wild-type and ten chimeric and truncated sigma1 proteins, the sialic acid-binding domain of type 3 sigma1 was mapped to a region of sequence proposed to form the more amino terminal of two predicted beta-sheet structures in the tail. This unit corresponds to morphologic region T(iii) observed in computer-processed electron micrographs of sigma1 protein purified from virions. In contrast, the homologous region of T1L sigma1 sequence was not implicated in carbohydrate binding; rather, sequences in the distal portion of the tail known as the neck were required. Results of these studies demonstrate that a functional receptor-binding domain, which uses sialic acid as its ligand, is contained within morphologic region T(iii) of the type 3 sigma1 tail. Furthermore, our findings indicate that T1L and T3D sigma1 proteins contain different arrangements of receptor-binding

  13. Simple synthesis, structure and ab initio study of 1,4-benzodiazepine-2,5-diones

    Science.gov (United States)

    Jadidi, Khosrow; Aryan, Reza; Mehrdad, Morteza; Lügger, Thomas; Ekkehardt Hahn, F.; Ng, Seik Weng

    2004-04-01

    A simple procedure for the synthesis of pyrido[2,1-c][1,4] benzodiazepine-6,12-dione ( 1) and 1,4-benzodiazepine-2,5-diones ( 2a- 2d), using microwave irradiation and/or conventional heating is reported. The configuration of 1 was determined by single-crystal X-ray diffraction. A detailed ab initio B3LYP/6-31G* calculation of structural parameters and substituent effects on ring inversion barriers (Δ G#) and also free energy differences (Δ G0) for benzodiazepines are reported.

  14. 1,4-Benzodiazepine N-Nitrosoamidines: Useful Intermediates in the Synthesis of Tricyclic Benzodiazepines

    Directory of Open Access Journals (Sweden)

    Carlos del Pozo

    2006-08-01

    Full Text Available 1,4-Benzodiazepine N-nitrosoamidines have been used as scaffolds for the preparation of different tricyclic derivatives. Replacement of the N-nitrosoamidine moiety through treatment with the nucleophiles acetylhydrazine, aminoacetaldehyde dimethylacetal and 1-amino-2-propanol, followed by an acid-catalyzed cyclization step, afforded triazolo and imidazobenzodiazepines 1, 6, and 7, respectively, in good yields. When acetylhydrazine is used as a nucleophile, the overall process provides an alternative route to alprazolam (1b and triazolam (1c, respectively.

  15. The decorin sequence SYIRIADTNIT binds collagen type I

    DEFF Research Database (Denmark)

    Kalamajski, Sebastian; Aspberg, Anders; Oldberg, Ake

    2007-01-01

    Decorin belongs to the small leucine-rich repeat proteoglycan family, interacts with fibrillar collagens, and regulates the assembly, structure, and biomechanical properties of connective tissues. The decorin-collagen type I-binding region is located in leucine-rich repeats 5-6. Site......-directed mutagenesis of this 54-residue-long collagen-binding sequence identifies Arg-207 and Asp-210 in leucine-rich repeat 6 as crucial for the binding to collagen. The synthetic peptide SYIRIADTNIT, which includes Arg-207 and Asp-210, inhibits the binding of full-length recombinant decorin to collagen in vitro....... These collagen-binding amino acids are exposed on the exterior of the beta-sheet-loop structure of the leucine-rich repeat. This resembles the location of interacting residues in other leucine-rich repeat proteins....

  16. Assessment of dependence and anxiety among benzodiazepine users in a provincial municipality in Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Janaína Barden Schallemberger

    Full Text Available Abstract Introduction: Benzodiazepines are among the most prescribed drugs for anxiety and one of the most used drug classes in the world and have a high potential for addiction. The objective of this study was to assess levels of dependence and anxiety among users of these drugs in the public health system. Methods: This was a cross-sectional, descriptive and quantitative study. Benzodiazepine users treated on the public health system were selected. Anxiety levels were assessed with the Hamilton Anxiety Scale and dependency with the Benzodiazepine Dependence Self-Report Questionnaire. Results: Benzodiazepine use was higher among women and in older age groups. Duration of benzodiazepine use was greater than 1 year for all respondents. The dependence assessment indicated that more than half of users were dependent on taking benzodiazepines and most had a severe degree of anxiety. Conclusion: This study found evidence of prolonged and inappropriate use of benzodiazepines. It is necessary to educate users about the risks of these drugs and to develop strategies to rationalize use of these drugs by working with prescribers and dispensers.

  17. PTSD Symptom Severities, Interpersonal Traumas, and Benzodiazepines Are Associated with Substance-Related Problems in Trauma Patients

    Science.gov (United States)

    Guina, Jeffrey; Nahhas, Ramzi W.; Goldberg, Adam J.; Farnsworth, Seth

    2016-01-01

    Background: Trauma is commonly associated with substance-related problems, yet associations between specific substances and specific posttraumatic stress disorder symptoms (PTSSs) are understudied. We hypothesized that substance-related problems are associated with PTSS severities, interpersonal traumas, and benzodiazepine prescriptions. Methods: Using a cross-sectional survey methodology in a consecutive sample of adult outpatients with trauma histories (n = 472), we used logistic regression to examine substance-related problems in general (primary, confirmatory analysis), as well as alcohol, tobacco, and illicit drug problems specifically (secondary, exploratory analyses) in relation to demographics, trauma type, PTSSs, and benzodiazepine prescriptions. Results: After adjusting for multiple testing, several factors were significantly associated with substance-related problems, particularly benzodiazepines (AOR = 2.78; 1.99 for alcohol, 2.42 for tobacco, 8.02 for illicit drugs), DSM-5 PTSD diagnosis (AOR = 1.92; 2.38 for alcohol, 2.00 for tobacco, 2.14 for illicit drugs), most PTSSs (especially negative beliefs, recklessness, and avoidance), and interpersonal traumas (e.g., assaults and child abuse). Conclusion: In this clinical sample, there were consistent and strong associations between several trauma-related variables and substance-related problems, consistent with our hypotheses. We discuss possible explanations and implications of these findings, which we hope will stimulate further research, and improve screening and treatment. PMID:27517964

  18. PTSD Symptom Severities, Interpersonal Traumas, and Benzodiazepines Are Associated with Substance-Related Problems in Trauma Patients

    Directory of Open Access Journals (Sweden)

    Jeffrey Guina

    2016-08-01

    Full Text Available Background: Trauma is commonly associated with substance-related problems, yet associations between specific substances and specific posttraumatic stress disorder symptoms (PTSSs are understudied. We hypothesized that substance-related problems are associated with PTSS severities, interpersonal traumas, and benzodiazepine prescriptions. Methods: Using a cross-sectional survey methodology in a consecutive sample of adult outpatients with trauma histories (n = 472, we used logistic regression to examine substance-related problems in general (primary, confirmatory analysis, as well as alcohol, tobacco, and illicit drug problems specifically (secondary, exploratory analyses in relation to demographics, trauma type, PTSSs, and benzodiazepine prescriptions. Results: After adjusting for multiple testing, several factors were significantly associated with substance-related problems, particularly benzodiazepines (AOR = 2.78; 1.99 for alcohol, 2.42 for tobacco, 8.02 for illicit drugs, DSM-5 PTSD diagnosis (AOR = 1.92; 2.38 for alcohol, 2.00 for tobacco, 2.14 for illicit drugs, most PTSSs (especially negative beliefs, recklessness, and avoidance, and interpersonal traumas (e.g., assaults and child abuse. Conclusion: In this clinical sample, there were consistent and strong associations between several trauma-related variables and substance-related problems, consistent with our hypotheses. We discuss possible explanations and implications of these findings, which we hope will stimulate further research, and improve screening and treatment.

  19. Synthesis, Anticonvulsant, Sedative and Anxiolytic Activities of Novel Annulated Pyrrolo[1,4]benzodiazepines

    Directory of Open Access Journals (Sweden)

    Kumaraswamy Sorra

    2014-09-01

    Full Text Available Four new pentacyclic benzodiazepine derivatives (PBDTs 13–16 were synthesized by conventional thermal heating and microwave-assisted intramolecular cyclocondensation. Their anticonvulsant, sedative and anxiolytic activities were evaluated by drug-induced convulsion models, a pentobarbital-induced hypnotic model and an elevated plus maze in mice. PBDT 13, a triazolopyrrolo[2,1-c][1,4]benzodiazepin-8-one fused with a thiadiazolone ring, exhibited the best anticonvulsant, sedative and anxiolytic effects in our tests. There was no significant difference in potency between PBDT 13 and diazepam, and we proposed that the action mechanism of PBDT 13 could be similar to that of diazepam via benzodiazepine receptors.

  20. Cell-type specificity of ChIP-predicted transcription factor binding sites

    Directory of Open Access Journals (Sweden)

    Håndstad Tony

    2012-08-01

    Full Text Available Abstract Background Context-dependent transcription factor (TF binding is one reason for differences in gene expression patterns between different cellular states. Chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq identifies genome-wide TF binding sites for one particular context—the cells used in the experiment. But can such ChIP-seq data predict TF binding in other cellular contexts and is it possible to distinguish context-dependent from ubiquitous TF binding? Results We compared ChIP-seq data on TF binding for multiple TFs in two different cell types and found that on average only a third of ChIP-seq peak regions are common to both cell types. Expectedly, common peaks occur more frequently in certain genomic contexts, such as CpG-rich promoters, whereas chromatin differences characterize cell-type specific TF binding. We also find, however, that genotype differences between the cell types can explain differences in binding. Moreover, ChIP-seq signal intensity and peak clustering are the strongest predictors of common peaks. Compared with strong peaks located in regions containing peaks for multiple transcription factors, weak and isolated peaks are less common between the cell types and are less associated with data that indicate regulatory activity. Conclusions Together, the results suggest that experimental noise is prevalent among weak peaks, whereas strong and clustered peaks represent high-confidence binding events that often occur in other cellular contexts. Nevertheless, 30-40% of the strongest and most clustered peaks show context-dependent regulation. We show that by combining signal intensity with additional data—ranging from context independent information such as binding site conservation and position weight matrix scores to context dependent chromatin structure—we can predict whether a ChIP-seq peak is likely to be present in other cellular contexts.

  1. Benzodiazepine use in medical out-patient clinics: a study from a developing country

    International Nuclear Information System (INIS)

    Patel, M.J.; Ahmer, S.; Khan, F.; Qureshi, A.W.A.; Shehzad, M.F.

    2013-01-01

    Objective: To estimate the prevalence of Benzodiazepine use in the outpatient setting of general medicine clinics at a single tertiary care centre. Methods: The prospective prevalence study was conducted in the outpatient setting of Internal Medicine Clinics at Aga Khan University Hospital, Karachi, from November to December 2009. All subjects were interviewed after informed consent and variables were recorded on a specially-designed proforma. Apart from basic demographics and comorbid conditions, duration, frequency and route of benzodiazepine use, as well as the reason and who initiated it was noted. Chi-square test and t test was applied to see the association of socio demographic or clinical factors with the use of benzodiazepine. Results: Of the 355 patients, 129 (36.33%) reported using the drug. The majority (n=86; 24.2%) were taking it on a daily basis. The highest numbers of patients using the drug were suffering from cardiovascular problems, 32 (25%) followed by 22 (17%) from endocrinology. Diazepam equivalent dose was around 7.04+-4, with a inter-quartile range of 3-96 weeks. Alprazolam (9%) was the most frequently prescribed Benzodiazepine. Conclusion: Benzodiazepine use is alarmingly high in the outpatient clinics of General Internal Medicine Department. There is no implementation of law to prevent its hazardous sale. In this regard all concerned should work collectively for awareness and irrational drug sale and use. (author)

  2. Quantitative analysis of benzodiazepines in vitreous humor by high-performance liquid chromatography

    Science.gov (United States)

    Bazmi, Elham; Behnoush, Behnam; Akhgari, Maryam; Bahmanabadi, Leila

    2016-01-01

    Objective: Benzodiazepines are frequently screened drugs in emergency toxicology, drugs of abuse testing, and in forensic cases. As the variations of benzodiazepines concentrations in biological samples during bleeding, postmortem changes, and redistribution could be biasing forensic medicine examinations, hence selecting a suitable sample and a validated accurate method is essential for the quantitative analysis of these main drug categories. The aim of this study was to develop a valid method for the determination of four benzodiazepines (flurazepam, lorazepam, alprazolam, and diazepam) in vitreous humor using liquid–liquid extraction and high-performance liquid chromatography. Methods: Sample preparation was carried out using liquid–liquid extraction with n-hexane: ethyl acetate and subsequent detection by high-performance liquid chromatography method coupled to diode array detector. This method was applied to quantify benzodiazepines in 21 authentic vitreous humor samples. Linear curve for each drug was obtained within the range of 30–3000 ng/mL with coefficient of correlation higher than 0.99. Results: The limit of detection and quantitation were 30 and 100 ng/mL respectively for four drugs. The method showed an appropriate intra- and inter-day precision (coefficient of variation forensic toxicology laboratory. PMID:27635251

  3. Synthesis of Riboflavines, Quinoxalinones and Benzodiazepines through Chemoselective Flow Based Hydrogenations

    Directory of Open Access Journals (Sweden)

    Marcus Baumann

    2014-07-01

    Full Text Available Robust chemical routes towards valuable bioactive entities such as riboflavines, quinoxalinones and benzodiazepines are described. These make use of modern flow hydrogenation protocols enabling the chemoselective reduction of nitro group containing building blocks in order to rapidly generate the desired amine intermediates in situ. In order to exploit the benefits of continuous processing the individual steps were transformed into a telescoped flow process delivering selected benzodiazepine products on scales of 50 mmol and 120 mmol respectively.

  4. An electronic intervention to improve safety for pain patients co-prescribed chronic opioids and benzodiazepines.

    Science.gov (United States)

    Zaman, Tauheed; Rife, Tessa L; Batki, Steven L; Pennington, David L

    2018-03-29

    Co-prescribing opioids and benzodiazepines increases overdose risk. A paucity of literature exists evaluating strategies to improve safety of co-prescribing. This study evaluated an electronic intervention to improve safety for patients co-prescribed chronic opioids for pain and benzodiazepines at 3 and 6 months. A prospective cohort study was conducted from December 2015 through May 2016 at San Francisco Veterans Affairs Health Care System. A clinical dashboard identified 145 eligible patients prescribed chronic opioids and benzodiazepines. Individualized taper and safety recommendations were communicated to prescribers via electronic medical record progress note and encrypted e-mail at baseline. Primary outcome was number of patients co-prescribed chronic opioids and benzodiazepines. Secondary outcomes included daily dose of opioids and benzodiazepines and number prescribed ≥100 mg morphine equivalent daily dose. Safety outcomes included number with opioid overdose education and naloxone distribution, annual urine drug screening, annual prescription drug monitoring program review, and signed opioid informed consent. Linear mixed models and generalized estimating equations were used to examine within-group change in outcomes between baseline and 3 and 6 months. Among the 145 patients, mean (standard deviation) age was 62 (11) years and 91.7% (133/145) were male. Number co-prescribed significantly decreased from 145/145 (100%) at baseline to 93/139 (67%) at 6-month follow-up (odds ratio [OR] = 0.53, 95% confidence interval [CI]: 0.34-0.81, P = .003). Mean opioid and benzodiazepine doses significantly decreased from 84.61 to 65.63 mg (95% CI: 8.32-27.86, P improve safety for patients co-prescribed chronic opioids for pain and benzodiazepines.

  5. Saturable binding of 35S-t-butylbicyclophosphorothionate to the sites linked to the GABA receptor and the interaction with gabaergic agents

    International Nuclear Information System (INIS)

    Wong, D.T.; Threlkeld, P.G.; Bymaster, F.P.; Squires, R.F.

    1984-01-01

    35 -S-t-Butylbicyclophosphorothionate ( 35 S-TBPS) binds in a concentration-saturable manner to specific sites on membranes from rat cerebral cortex. Using a filtration assay at 25 0 C, in 250 mM NaCl, specific binding of 35 S-TBPS constitutes about 84 to 94 percent of total binding, depending on radioligand concentrations. 35 S-TBPS binding is optimal in the presence of NaCl or NaBr and substantially less in the presence of NaI or NaF. It is sensitive to the treatment with 0.05 percent Triton X-100 but not to repeated freezing and thawing, procedures which increase 3 H-GABA binding. Pharmacological studies show that 35 S-TBPS binding is strongly inhibited by GABA-A receptor agonists (e.g., GABA and muscimol) and by the noncompetitive antagonist, picrotoxin, but not the competitive antagonist, bicuculline. Compounds which enhance binding of radioactive GABA and benzodiazepines, such as the pyrazolopyridines, cartazolate and trazolate, and a diaryl-triazine, LY81067, are also potent inhibitors of 35 S-TBPS binding, with LY81067 being the most effective. The effects of GABA, picrotoxin and LY81067 on the saturable binding of 35 S-TBPS in cortical membranes are compared. The present bindings are consistent with the interpretation that 35 S-TBPS binds, at or near the picrotoxin-sensitive anion recognition sites of the GABA/benzodiazepine/picrotoxin receptor complex

  6. A Pharmacist-Physician Collaboration to Optimize Benzodiazepine Use for Anxiety and Sleep Symptom Control in Primary Care.

    Science.gov (United States)

    Furbish, Shannon M L; Kroehl, Miranda E; Loeb, Danielle F; Lam, Huong Mindy; Lewis, Carmen L; Nelson, Jennifer; Chow, Zeta; Trinkley, Katy E

    2017-08-01

    Benzodiazepines are prescribed inappropriately in up to 40% of outpatients. The purpose of this study is to describe a collaborative team-based care model in which clinical pharmacists work with primary care providers (PCPs) to improve the safe use of benzodiazepines for anxiety and sleep disorders and to assess the preliminary results of the impact of the clinical service on patient outcomes. Adult patients were eligible if they received care from the academic primary care clinic, were prescribed a benzodiazepine chronically, and were not pregnant or managed by psychiatry. Outcomes included baseline PCP confidence and knowledge of appropriate benzodiazepine use, patient symptom severity, and medication changes. Twenty-five of 57 PCPs responded to the survey. PCPs reported greater confidence in diagnosing and treating generalized anxiety and panic disorders than sleep disorder and had variable knowledge of appropriate benzodiazepine prescribing. Twenty-nine patients had at least 1 visit. Over 44 total patient visits, 59% resulted in the addition or optimization of a nonbenzodiazepine medication and 46% resulted in the discontinuation or optimization of a benzodiazepine. Generalized anxiety symptom severity scores significantly improved (-2.0; 95% confidence interval (CI): -3.57 to -0.43). Collaborative team-based models that include clinical pharmacists in primary care can assist in optimizing high-risk benzodiazepine use. Although these findings suggest improvements in safe medication use and symptoms, additional studies are needed to confirm these preliminary results.

  7. Neurocognitive performance, subjective well-being, and psychosocial functioning after benzodiazepine withdrawal in patients with schizophrenia or bipolar disorder

    DEFF Research Database (Denmark)

    Baandrup, Lone; Fagerlund, Birgitte; Glenthoj, Birte

    2017-01-01

    -tapering compared with normative data. Neither benzodiazepine withdrawal nor treatment group affected subjective well-being or psychosocial functioning. In conclusion, add-on melatonin does not seem to affect cognition, well-being, or psychosocial functioning in patients with severe mental illness. The observed......Chronic benzodiazepine use is common in patients with mental illness and is associated with cognitive impairment. It is unclear whether benzodiazepine-induced cognitive impairment is reversible. Amelioration of cognitive dysfunction may be facilitated during benzodiazepine tapering by add......-on melatonin due to its anti-inflammatory and neuroprotective properties. We examined how melatonin and benzodiazepine withdrawal affect cognition, subjective well-being, and psychosocial functioning. Eighty patients with schizophrenia or bipolar disorder were randomized to add-on treatment once daily...

  8. The influence of serotonin depletion on rat behavior in the Vogel test and brain 3H-zolpidem binding.

    Science.gov (United States)

    Nazar, M; Siemiatkowski, M; Bidziński, A; Członkowska, A; Sienkiewicz-Jarosz, H; Płaźnik, A

    1999-01-01

    The influence of p-chlorophenylalanine (p-CPA) and 5,7-dihydroxytryptamine (5,7-DHT)-induced serotonin depletion on rat behavior as well as on zolpidem's the behavioral effects and binding to some brain areas of zolpidem, was examined with the help of Vogel's punished drinking test and autoradiography, respectively. Moreover, changes in the serotonin levels and turnover rate were studied in the forebrain and brainstem of rats pretreated with various ligands at the benzodiazepine (BDZ) receptors (midazolam, bretazenil, abecarnil, zolpidem). These drugs were given at doses shown previously to significantly disinhibit animal behavior suppressed by punishment in the Vogel test (Nazar et al., 1997). It was found that serotonin decrease in the frontal cortex and hippocampus after p-CPA significantly and inversely correlated with rat behavior controlled by fear in the VT. p-CPA produced an anticonflict activity in the absence of effect on spontaneous drinking, pain threshold and motility of animals. All applied benzodiazepine receptor ligands decreased the 5-HT turnover rate in the frontal cortex and hippocampus, whereas in the brainstem only abecarnil and zolpidem diminished 5-hydroxyindoleacetic acid levels. This part of the study replicated earlier data with neurotoxins and indicated that the anxiolytic-like effect of 5-HT depletion in some models of anxiety did not depend on changes in animal appetitive behavior or stimulus control. Moreover, the fact that all nonselective and selective (zolpidem) agonists of the type 1 benzodiazepine receptors seemed to produce the same anticonflict effect and decreasing 5-HT turnover indicates that this subtype of benzodiazepine receptor may be important for the interaction between brain 5-HT and GABA/BDZ systems. Accordingly, it was found that serotonin decrease enhanced the anticonflict effect of zolpidem in the Vogel test and increased 3H-zolpidem binding to the occipital cortex and substantia nigra. Altogether, the present study

  9. Tryptic mapping and membrane topology of the benzodiazepine receptor alpha-subunit

    Energy Technology Data Exchange (ETDEWEB)

    Lentes, K.U.; Venter, J.C.

    1986-05-01

    Rat brain membrane benzodiazepine receptors (BZR) were photoaffinity labelled specifically (in presence or absence of 6 ..mu..M clonazepam) with 10 nM /sup 3/H-flunitrazepam (FNZ). Digestion of the FNZ-labelled, membrane-bound BZR with 200 ..mu..g trypsin/mg membrane protein yielded H/sub 2/O-soluble BZR-fragments of molecular mass (M/sub r/) 34, 31, 28, 24, 21, 18, 16, 12, 10 and 7kDa. Because the 34kDa-peptide is the largest fragment containing a FNZ-binding site they conclude that this represents the extracellular domain of the BZR. In the remaining pellet two labelled peptides with M/sub r/ of 44kDa and 28kDa were found that required the use of detergents for their solubilization; they therefore contain the membrane anchoring domain. Digestion of the 0.5% Na-deoxycholate solubilized, intact BZR (M/sub r/ 51kDa) resulted in the same tryptic pattern as the membrane form of the receptor plus two larger fragments of M/sub r/ 45kDa and 40kDa. Arrangement of all tryptic fragments with reference to the FNZ binding site reveals a membrane topology of the BZR alpha-subunit with 67% (34kDa) for the extracellular domain, 21% (11kDa) for the membrane anchoring domain and 12% (6kDa) for a putative cytoplasmic domain. The overlap between some of the labelled fragments suggest that the BZ binding site must be located near the membrane surface of the extracellular domain.

  10. The benzodiazepine withdrawal syndrome and its management.

    OpenAIRE

    Onyett, S R

    1989-01-01

    The literature on benzodiazepine dependence and withdrawal is reviewed with an emphasis on social and psychological considerations. The problems of when to prescribe, identifying withdrawal symptoms, effective communication with the patient, the structure of withdrawal programmes, and the use of drugs, psychological approaches and other services are discussed.

  11. Benzodiazepine Consumption Is Associated With Lower Blood Pressure in Ambulatory Blood Pressure Monitoring (ABPM): Retrospective Analysis of 4938 ABPMs.

    Science.gov (United States)

    Mendelson, Nitsan; Gontmacher, Bella; Vodonos, Allina; Novack, Victor; Abu-AjAj, Muhammad; Wolak, Arik; Shalev, Haddar; Wolak, Talya

    2018-03-10

    The effect of chronic benzodiazepine use on blood pressure has not been documented. We aimed to evaluate whether regular benzodiazepine use can be associated to the results of ambulatory blood pressure monitoring (ABPM). A retrospective analysis of the ABPM database between 2009 and 2015 was performed. The study groups were divided according to benzodiazepine treatment at least 3 months before ABPM. Generalized estimating equation (GEE) model analysis was conducted to estimate the association between benzodiazepine treatment and ABPM test measurements. Multivariable COX regression survival analysis model for mortality and cardiovascular (CV) events was performed. A total of 4,938 ABPM studies were included in final analysis, 670 ABPMs of benzodiazepine-treated patients, and 4,268 of untreated patients. The benzodiazepine-treated group was significantly older, with a predominance of female patients, comprised more diabetic patients and consumed more antihypertensive medications. Adjustment for age, gender, diabetes mellitus, and number of antihypertensive medications, showed an association between benzodiazepine treatment and significantly lower ABPM measurements. When the analysis was split into those ≥60 years old and the other ABPM measurements only among ≥60 years old. Multivariable Cox regression survival analysis showed that regular benzodiazepine consumption was not associated with increased mortality or CV events (mean follow-up period of 42.4 ± 19.8 and 42.1 ± 20.0 months, respectively). Long-term use of benzodiazepines by ≥60 years old was independently associated with lower diastolic and systolic blood pressure in all parameters of ABPM, but not among younger patients.

  12. Analysis of binding energy activity of TIBO and HIV-RT based on ...

    African Journals Online (AJOL)

    Tetrahydro-imidazo[4,5,l-jk][1,4]-benzodiazepin-2 (1 H)one (TIBO) is a noncompetitive non nucleotide antiretroviral drug with a specific allosteric binding site of HIV-1 RT. The conformational analysis shows that the effect of the drug depends on the potential energy which varied due to the beta rotatable dihedral angles (N6 ...

  13. Use of benzodiazepines or benzodiazepine related drugs and the risk of cancer: a population-based case-control study

    DEFF Research Database (Denmark)

    Pottegård, Anton; Friis, Søren; Andersen, Morten

    2013-01-01

    AIM: Studies of the carcinogenic potential of benzodiazepines and related drugs (BZRD) have been equivocal. A recent study reported a 35% excess cancer risk among users of hypnotics, including benzodiazepines. METHOD: Using Danish nationwide registers, we conducted a matched case-control study...... of the association between BZRD and cancer risk. During 1 January 2002 and 31 December 2009, we identified 152 510 cases with a first time cancer who were matched (1:8) by age and gender to 1,220,317 cancer-free controls. A new-user design was applied by excluding all subjects who had used anxiolytics, hypnotics.......02), liver 1.81 (95% CI 1.18, 2.80), lung 1.38 (95% CI 1.23, 1.54), pancreas 1.35 (95% CI 1.02, 1.79) and kidney 1.39 (95% CI 1.01, 1.91). For tobacco-related cancers, the OR was 1.15 (95% CI 1.09, 1.22) and for the remaining cancer sites 1.01 (95% CI 0.94, 1.08). Sub-group analyses revealed only small...

  14. Reduction of GABA/sub B/ receptor binding induced by climbing fiber degeneration in the rat cerebellum

    International Nuclear Information System (INIS)

    Kato, K.; Fukuda, H.

    1985-01-01

    When the rat cerebellar climbing fibers degenerated, as induced by lesioning the inferior olive with 3-acetylpyridine (3-AP), GABA/sub B/ receptor binding determined with 3 H-(+/-)baclofen was reduced in the cerebellum but not in the cerebral cortex of rats. Computer analysis of saturation data revealed two components of the binding sites, and indicated that decrease of the binding in the cerebellum was due to reduction in receptor density, mainly of the high-affinity sites, the B/sub max/ of which was reduced to one-third that in the control animals. In vitro treatment with 3-AP, of the membranes prepared from either the cerebellum or the cerebral cortex, induced no alteration in the binding sites, thereby indicating that the alteration of GABA/sub B/ sites induced by in vivo treatment with 3-AP is not due to a direct action of 3-AP on the receptor. GABA/sub A/ and benzodiazepine receptor binding labelled with 3 H-muscimol and 3 H-diazepam, respectively, in both of brain regions was not affected by destruction of the inferior olive. These results provide evidence that some of the GABA/sub B/ sites but neither GABA/sub A/ nor benzodiazepine receptors in the cerebellum are located at the climbing fiber terminals. 28 references, 4 figures, 2 tables

  15. Prolonged-release melatonin versus placebo for benzodiazepine discontinuation in patients with schizophrenia: a randomized clinical trial - the SMART trial protocol

    DEFF Research Database (Denmark)

    Baandrup, Lone; Fagerlund, Birgitte; Jennum, Poul

    2011-01-01

    Treatment of schizophrenia frequently includes prolonged benzodiazepine administration despite a lack of evidence of its use. It is often difficult to discontinue benzodiazepines because of the development of dependence. We aim to assess if melatonin can facilitate the withdrawal of prolonged...... benzodiazepine administration in patients with schizophrenia. Furthermore, we aim to investigate the association of benzodiazepine dose reduction with the following clinically important variables: sleep, psychophysiology, cognition, social function, and quality of life....

  16. The pancreatic zymogen granule membrane protein, GP2, binds Escherichia coli type 1 Fimbriae

    Directory of Open Access Journals (Sweden)

    Lowe Anson W

    2009-07-01

    Full Text Available Abstract Background GP2 is the major membrane protein present in the pancreatic zymogen granule, and is cleaved and released into the pancreatic duct along with exocrine secretions. The function of GP2 is unknown. GP2's amino acid sequence is most similar to that of uromodulin, which is secreted by the kidney. Recent studies have demonstrated uromodulin binding to bacterial Type 1 fimbria. The fimbriae serve as adhesins to host receptors. The present study examines whether GP2 also shares similar binding properties to bacteria with Type 1 fimbria. Commensal and pathogenic bacteria, including E. coli and Salmonella, express type 1 fimbria. Methods An in vitro binding assay was used to assay the binding of recombinant GP2 to defined strains of E. coli that differ in their expression of Type 1 fimbria or its subunit protein, FimH. Studies were also performed to determine whether GP2 binding is dependent on the presence of mannose residues, which is a known determinant for FimH binding. Results GP2 binds E. coli that express Type 1 fimbria. Binding is dependent on GP2 glycosylation, and specifically the presence of mannose residues. Conclusion GP2 binds to Type 1 fimbria, a bacterial adhesin that is commonly expressed by members of the Enterobacteriacae family.

  17. Benzodiazepine receptor imaging with iomazenil SPECT in aphasic patients with cerebral infarction

    Energy Technology Data Exchange (ETDEWEB)

    Koshi, Yasuhiko; Kitamura, Shin; Ohyama, Masashi [Nippon Medical School, Tokyo (Japan)] (and others)

    1999-08-01

    To investigate the relationship between prognosis of aphasia and neuronal damage in the cerebral cortex, we evaluated the distribution of central-type benzodiazepine receptor (BZR) binding in post-stroke aphasics with [{sup 123}I]iomazenil and SPECT. We performed iomazenil SPECT in six aphasic patients (aged from 45 to 75 years; all right-handed) with unilateral left cerebral infarction. Three patients showed signs of Broca's aphasia and the other three Wernicke's aphasia. Cerebral blood flow (CBF) imaging was performed with [{sup 123}I]iodoamphetamine (IMP). The regions of interest (ROIs) on both images were set in the cerebral cortex, cerebellar cortex and language relevant area in both hemispheres. Three patients were classified in the mild prognosis group and the other three in the moderate prognosis group. The left language-relevant area was more closely concerned with the difference in aphasic symptoms than the right one in both BZR and CBF distribution, but the ipsilateral to the contralateral ratio (I/C ratio) in the language-relevant areas in the BZR distribution was significantly lower in the moderate prognosis group than in the mild prognosis group, although no difference was seen for these values between the two groups in the CBF distribution. These results suggest that BZR imaging, which makes possible an increase in neuronal cell viability in the cerebral cortex, is useful not only for clarifying the aphasic symptoms but also for evaluating the prognosis of aphasia in patients with cerebral infarction. (author)

  18. Benzodiazepine receptor imaging with iomazenil SPECT in aphasic patients with cerebral infarction

    International Nuclear Information System (INIS)

    Koshi, Yasuhiko; Kitamura, Shin; Ohyama, Masashi

    1999-01-01

    To investigate the relationship between prognosis of aphasia and neuronal damage in the cerebral cortex, we evaluated the distribution of central-type benzodiazepine receptor (BZR) binding in post-stroke aphasics with [ 123 I]iomazenil and SPECT. We performed iomazenil SPECT in six aphasic patients (aged from 45 to 75 years; all right-handed) with unilateral left cerebral infarction. Three patients showed signs of Broca's aphasia and the other three Wernicke's aphasia. Cerebral blood flow (CBF) imaging was performed with [ 123 I]iodoamphetamine (IMP). The regions of interest (ROIs) on both images were set in the cerebral cortex, cerebellar cortex and language relevant area in both hemispheres. Three patients were classified in the mild prognosis group and the other three in the moderate prognosis group. The left language-relevant area was more closely concerned with the difference in aphasic symptoms than the right one in both BZR and CBF distribution, but the ipsilateral to the contralateral ratio (I/C ratio) in the language-relevant areas in the BZR distribution was significantly lower in the moderate prognosis group than in the mild prognosis group, although no difference was seen for these values between the two groups in the CBF distribution. These results suggest that BZR imaging, which makes possible an increase in neuronal cell viability in the cerebral cortex, is useful not only for clarifying the aphasic symptoms but also for evaluating the prognosis of aphasia in patients with cerebral infarction. (author)

  19. Altered SPECT 123I iomazenil Binding in the Cingulate Cortex of Children with Anorexia Nervosa

    Directory of Open Access Journals (Sweden)

    Shinichiro eNagamitsu

    2016-02-01

    Full Text Available Several lines of evidence suggest that anxiety plays a key role in the development and maintenance of anorexia nervosa (AN in children. The purpose of this study was to examine cortical GABA(A-benzodiazepine receptor binding before and after treatment in children beginning intensive AN treatment. Brain single photon emission computed tomography (SPECT measurements using 123I iomazenil, which binds to GABA(A-benzodiazepine receptors, was performed in 26 participants with AN who were enrolled in a multimodal treatment program. Sixteen of the 26 participants underwent a repeat SPECT scan immediately before discharge at conclusion of the intensive treatment program. Eating behavior and mood disturbances were assessed using Eating Attitudes Test with 26 items (EAT-26 and the short form of the Profile of Mood States (POMS. Clinical outcome scores were evaluated after a 1-year period. We examined association between relative iomazenil binding activity in cortical regions of interest (ROIs and psychometric profiles, and determined which psychometric profiles show interaction effects with brain regions. Further, we determined if binding activity could predict clinical outcome and treatment changes. Higher EAT-26 scores were significantly associated with lower iomazenil binding activity in the anterior posterior cingulate cortex (ACC. Higher POMS subscale scores were significantly associated with lower iomazenil binding activity in the left frontal, parietal cortex, and posterior cingulate cortex (PCC. Depression-Dejection, and Confusion POMS subscale scores, and total POMS score, showed interaction effects with brain regions in iomazenil binding activity. Decreased binding in the ACC and left parietal cortex was associated with poor clinical outcomes. Relative binding increases throughout the PCC and occipital gyrus were observed after weight gain in children with AN. These findings suggest that cortical GABAergic receptor binding is altered in children

  20. Analysis of benzodiazepines and their metabolites using DBS cards and LC-MS/MS.

    Science.gov (United States)

    Lee, Heesang; Park, Yujin; Jo, Jiyeong; In, Sangwhan; Park, Yonghoon; Kim, Eunmi; Pyo, Jaesung; Choe, Sanggil

    2015-10-01

    Dried Blood Spot (DBS) has been used a blood extraction method for inherited metabolic disorder screening since 1960s. With introduction of LC-MS/MS, not only DBS could be used to analysis drugs in small blood volume, but in various fields, such as toxicology, drug therapeutic monitoring, drug diagnostic screening, and illicit drugs. In toxicology field, many drugs (e.g. benzodiazepines, acetaminophen, small molecule drugs) have been tested with DBS. Compared with earlier blood extraction methods (SPE and LLE), DBS has lots of advantages; lower blood volume (less than 50μL), shorter analysis time caused by a more concise analysis procedure and lower cost. We optimized the DBS procedure and LC-MS/MS conditions for 18 benzodiazepines, seven benzodiazepine metabolites, and one z-drug (zolpidem) analysis in blood. 30μL of whole blood was spotted on FTA DMPK card C and dried for 2h in a desiccator. A 6-mm disk was punched and vortexed for 1min in a centrifuge tube with 300μL methanol/acetonitrile mixture (1:1, v/v). After evaporation, redissolved in 100μL mobile phase of LC-MS/MS and 5μL was injected. In the analysis for 26 target compounds in blood, all of the method validation parameters - LLOD, LLOQ, accuracy (intra- and inter-assay), and precision (intra- and inter-assay) - were satisfied with method validation criteria, within 15%. The results of matrix effect, recovery, and process efficiency were good. We developed a fast and reliable sample preparation method using DBS for 26 benzodiazepines, benzodiazepine metabolites, and z-drug (zolpidem). Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. Stories of Hell and Healing: Internet Users' Construction of Benzodiazepine Distress and Withdrawal.

    Science.gov (United States)

    Fixsen, Alison M; Ridge, Damien

    2017-11-01

    Benzodiazepines are a group of drugs used mainly as sedatives, hypnotics, antiepileptics, and muscle relaxants. Consumption is recommended for 2 to 4 weeks only, due to fast onset of dependency and potentially distressing withdrawal symptoms. Few peer-review studies have drawn on the user experiences and language to appreciate firsthand experiences of benzodiazepine withdrawal or discontinuation syndrome. We looked extensively at patient stories of benzodiazepine withdrawal and recovery on Internet support sites and YouTube. Our analysis indicated that users employ rich metaphors to portray the psychologically disturbing and protracted nature of their suffering. We identified seven major themes: hell and isolation, anxiety and depression, alienation, physical distress, anger and remorse, waves and windows, and healing and renewal. By posting success stories, ex-users make known that "healing" can be a long, unpredictable process, but distress does lessen, and recovery can happen.

  2. GABAA [gamma-aminobutyric acid] type binding sites on membranes of spermatozoa

    International Nuclear Information System (INIS)

    Erdoe, S.L.; Wekerle, L.

    1990-01-01

    The binding of [ 3 H] gamma-aminobutyric acid (GABA) to seminal membranes of swines and rams was examined. Specific, GABA binding was demonstrated in both species, which showed the features of GABA A type receptors. The affinity of binding was similar in both species, whereas the density of seminal GABA binding sites was 5 times higher in swine. Our findings suggest that GABA may have a direct effect on spermatozoa

  3. [Benzodiazepin addiction: a silent addiction among older people].

    NARCIS (Netherlands)

    Oude Voshaar, R.C.

    2012-01-01

    Benzodiazepines are frequently prescribed for a longer period of time for anxiety disorders and insomnia in spite of the many guidelines to prescribe these drugs only short-term. These guidelines are based on the risk-benefit balance between long-term effectiveness and side effects like addiction,

  4. Attention Span, Anxiety and Benzodiazepine Receptors

    Science.gov (United States)

    1991-02-26

    increasse the central and peripheral effects of emotional stress ,-- FL combines 0nly the clinically favorable attributes of both classes of drugs, as...Pieri, P. PoIc. E.P. Bonetti, P. Cumin , R. Schaffner and W. Haefely, 1981, Selective antagonist of benzodiazepines, Nature 290, 514. Karobath, M. and G...34intimidaring" and/or stressful stimuli. In such a condition, flumazenil can be expected to have a stabilizing effect on emotional responses normally triggered

  5. Value of heart-type fatty acid-binding protein (H-FABP) for ...

    African Journals Online (AJOL)

    Key Words: heart-type fatty acid-binding protein, acute coronary syndrome, biomarker. ... is essential to prevent major complications and death. Routinely used biomarkers such ..... fatty acid binding proteins: their function and physiological sig-.

  6. SYNTHESIS OF 1,2 FUSED SYSTEMS BASED ON THE 3-ARYLIDENE-5-PHENYL-1,2-DIHYDRO-3H-1,4- BENZODIAZEPINE-2-ONES

    Directory of Open Access Journals (Sweden)

    V. I. Pavlovsky

    2014-12-01

    Full Text Available By the reaction of 7-bromo-5-aryl-1,2-dihydro-3H-1,4-benzodiazepine-2-ones with Lawesson reagent, 7-bromo-5-aryl-1,2-dihydro-3H-1,4-benzodiazepine-2-tiones were synthesized from which 3-arylidene-7-bromo-2-hydrazino-5-phenyl-3H-1,4-benzodiazepines were obtained by the reaction with hydrazine hydrate. The condensation of 3-arylidene-7-bromo-2-hydrazino-5-phenyl-3H-1,4-benzodiazepines with triethylorthoformate (triethylorthoacetate or formic acid (acetic acid gave 4-arylidene-8-bromo-6-phenyl-4H-[1,2,4]triazolo[4,3-а][1,4]-benzodiazepines. Latter were also synthesized by the reaction of 7-bromo-5-aryl-1,2-dihydro-3H-1,4-benzodiazepine-2-tiones with acetylhydrazine. 4-Arylidene-8-bromo-6-phenyl-4H-[1,2,3,4] tetrazolo[1,5-а][1,4]-benzodiazepines were obtained by the reaction of 3-arylidene-7-bromo-2-hydrazino-5-phenyl-3H-1,4-benzodiazepines with sodium nitrite.

  7. Intramolecular Azide to Alkene Cycloadditions for the Construction of Pyrrolobenzodiazepines and Azetidino-Benzodiazepines

    Directory of Open Access Journals (Sweden)

    Karl Hemming

    2014-10-01

    Full Text Available The coupling of proline- and azetidinone-substituted alkenes to 2-azidobenzoic and 2-azidobenzenesulfonic acid gives precursors that undergo intramolecular azide to alkene 1,3-dipolar cycloadditions to give imine-, triazoline- or aziridine-containing pyrrolo[1,4]benzodiazepines (PBDs, pyrrolo[1,2,5]benzothiadiazepines (PBTDs, and azetidino[1,4]benzodiazepines. The imines and aziridines are formed after loss of nitrogen from a triazoline cycloadduct. The PBDs are a potent class of antitumour antibiotics.

  8. Reducing Prescriptions of Long-acting Benzodiazepine Drugs in Denmark

    DEFF Research Database (Denmark)

    Eriksen, Sophie Isabel; Bjerrum, Lars

    2015-01-01

    Prolonged consumption of benzodiazepine drugs (BZD) and benzodiazepine receptor agonists (zolpidem, zaleplon, zopiclone; altogether Z drugs) is related to potential physiological and psychological dependence along with other adverse effects. This study aimed to analyse the prescribing of long...... to the prescription. The observed reduction in BZD use was correlated to the introduction of new national guidelines on prescription of addictive drugs, but this study was not designed to detect a causal relationship. The prescribing of long-acting BZD decreased considerably more than the prescribing of short......-acting BZD (half-life >10 hr), compared to short-acting BZD in Denmark during a 10-year period. Descriptive analysis of total sales data from the Danish Register of Medicinal Product Statistics, to individuals in the primary healthcare sector, of all BZD and Z-drugs in the period of 2003-2013. Prescription...

  9. Atuoradiographic detection of multiple sclerosis plaques with an ω3 (peripheral type benzodiazepine) binding site radiogland

    International Nuclear Information System (INIS)

    HAUW, J.J.; Sazdovitch, V.; Cornu, P.; Dubois, A.; Benavides, J.; Mac Kenzie, E.; Scatton, B.

    1989-01-01

    In Multiple Sclerosis (MS), the presence of monocyte-macrophages and microglial cells in active plaques is a constant feature. They are numerous at the border of active lesions where they constiture, with other cell types such as lymphocytes and oligodendrocytes the so-called flial wall. Monocyte-macrophages and microglial cells are thought to be directly involved in the process of demyelination. Some macrophages laden with meylin degradation products are also seen in the center of the plaqie, often located in the perivascular cuffs. In addition, astrocytic gliosis occurs in the center of the plaques. As all these cell types are richly endowed with ω3 sites, the feasibility of using ω3 site autoradiagraphy to detect the demyelination plaques in the brain of post-mortem cases of Multiple Sclerosis has been investigated. (Author). 8 refs

  10. [Driving under the influence of benzodiazepines and antidepressants: prescription and abuse].

    Science.gov (United States)

    Coutinho, Daniel; Vieira, Duarte Nuno; Teixeira, Helena M

    2011-01-01

    Benzodiazepines are drugs usually used in anxiety disorders, dyssomnias, convulsions, muscle disorders, alcohol and other drugs detoxification, as well as in preoperative sedation/amnesia. Moreover, antidepressants are mainly indicated in depression and as co-therapeutic drugs in other psychiatric disorders. The use of benzodiazepines and antidepressants is associated with some health and public safety problems. Decreased of attention, concentration, reflexes, visual capacity, motor coordination and reasoning, associated with increased reaction time and lack of awareness of driving impairment among these drug users, contributes to the increased risk on traffic safety linked with these drugs. This risk may further increase with non-compliance of medical prescription, drug abuse or concomitant use of alcohol. The relationship between the use of psychoactive drugs and road traffic safety is, however, an extremely complex subject and has a primordial importance in the clarification of the role of benzodiazepine and antidepressant effects on driving skills. The prevention of driving under the influence of these drugs depends on the awareness, among doctors, of the risks associated with their use. Thus, the consciousness of medical prescription, as well as providing clear information to patients is extremely important.

  11. High daily doses of benzodiazepines among Quebec seniors: prevalence and correlates

    Directory of Open Access Journals (Sweden)

    Moride Yola

    2001-11-01

    Full Text Available Abstract Background Use of high daily doses of benzodiazepines is generally contraindicated for seniors. While both patient and physician factors may influence the use of high daily doses, previous research on the effect of patient factors has been extremely limited. The objectives of this study were to determine the one year prevalence of use of high daily doses of benzodiazepines, and examine physician and patient correlates of such use among Quebec community-dwelling seniors. Methods Patient information for 1423 community-dwelling Quebec seniors who participated in the Canadian Study of Health and Aging was linked to provincial health insurance administrative data bases containing detailed information on prescriptions received and prescribers. Results The standardized one year period prevalence of use of high daily doses of benzodiazepines was 7.9%. Use of high daily doses was more frequent among younger seniors and those who had reported anxiety during the previous year. Patients without cognitive impairment were more likely to receive high dose prescriptions from general practitioners, while those with cognitive impairment were more likely to receive high dose prescriptions from specialists. Conclusion High dose prescribing appears to be related to both patient and physician factors.

  12. Benzodiazepine receptor turnover in embryonic chick brain and spinal cord cell cultures

    International Nuclear Information System (INIS)

    Borden, L.A.

    1985-01-01

    The turnover (synthesis and degradation) of the benzodiazepine receptor (BZD-R) in embryonic chick brain and spinal cord cell cultures was monitored using flunitrazepam (GNZM) as a photoaffinity label. To measure BZD-R appearance, intact cell cultures were incubated with 100 nM RNZM and irradiated with ultraviolet light; this process, referred to as photoinactivation, resulted in a 75% decrease in the subsequent reversible binding of 5 nM [ 3 H]FNZM. Following photoinactivation, [ 3 H]FNZM binding sites reappeared at a rate of 6 +/- 1.5%/hour (n = 7) in brain cultures and at 8%/hour (n = 2) in spinal cord cultures. Reappearance reflects de novo receptors synthesis. To examine the degradation of existing receptors, cultures were photolabeled with 5 nM [ 3 H]FNZM, washed, and then the decrease in cell-associated radioactivity, or the efflux of radioactivity into the medium, was monitored. The released radioactivity did not comigrate with authentic FNZM on thin-layer-chromatographs, indicating that release did not represent dissociation of ligand from the photolabeled receptor. The BZD-R appears to be degraded by an energy-dependent, non-lysosomal pathway. These experiments represent the first direct examination of the turnover of a neurotransmitter receptor localized to the central nervous system; this information will be valuable in elucidating the mechanisms by which receptor levels are altered following chronic drug treatment

  13. Fungal-type carbohydrate binding modules from the coccolithophore Emiliania huxleyi show binding affinity to cellulose and chitin.

    Science.gov (United States)

    Rooijakkers, Bart J M; Ikonen, Martina S; Linder, Markus B

    2018-01-01

    Six fungal-type cellulose binding domains were found in the genome of the coccolithophore Emiliania huxleyi and cloned and expressed in Escherichia coli. Sequence comparison indicate high similarity to fungal cellulose binding domains, raising the question of why these domains exist in coccolithophores. The proteins were tested for binding with cellulose and chitin as ligands, which resulted in the identification of two functional carbohydrate binding modules: EHUX2 and EHUX4. Compared to benchmark fungal cellulose binding domain Cel7A-CBM1 from Trichoderma reesei, these proteins showed slightly lower binding to birch and bacterial cellulose, but were more efficient chitin binders. Finally, a set of cellulose binding domains was created based on the shuffling of one well-functioning and one non-functional domain. These were characterized in order to get more information of the binding domain's sequence-function relationship, indicating characteristic differences between the molecular basis of cellulose versus chitin recognition. As previous reports have showed the presence of cellulose in coccoliths and here we find functional cellulose binding modules, a possible connection is discussed.

  14. Fungal-type carbohydrate binding modules from the coccolithophore Emiliania huxleyi show binding affinity to cellulose and chitin.

    Directory of Open Access Journals (Sweden)

    Bart J M Rooijakkers

    Full Text Available Six fungal-type cellulose binding domains were found in the genome of the coccolithophore Emiliania huxleyi and cloned and expressed in Escherichia coli. Sequence comparison indicate high similarity to fungal cellulose binding domains, raising the question of why these domains exist in coccolithophores. The proteins were tested for binding with cellulose and chitin as ligands, which resulted in the identification of two functional carbohydrate binding modules: EHUX2 and EHUX4. Compared to benchmark fungal cellulose binding domain Cel7A-CBM1 from Trichoderma reesei, these proteins showed slightly lower binding to birch and bacterial cellulose, but were more efficient chitin binders. Finally, a set of cellulose binding domains was created based on the shuffling of one well-functioning and one non-functional domain. These were characterized in order to get more information of the binding domain's sequence-function relationship, indicating characteristic differences between the molecular basis of cellulose versus chitin recognition. As previous reports have showed the presence of cellulose in coccoliths and here we find functional cellulose binding modules, a possible connection is discussed.

  15. Estimation of Cessation Rates among Danish Users of Benzodiazepines

    DEFF Research Database (Denmark)

    Støvring, Henrik; Gasse, Christiane

    Background: Widespread and longterm use of benzodiazepines constitute a public health problem. Health care authorities hence advice that use should not exceed three months, in particular for the elderly and patients with a past diagnosis of drug addiction. Objectives: Estimate the shape...

  16. Benzodiazepines and antipsychotic medications for treatment of acute cocaine toxicity in animal models--a systematic review and meta-analysis.

    Science.gov (United States)

    Heard, Kennon; Cleveland, Nathan R; Krier, Shay

    2011-11-01

    There are no controlled human studies to determine the efficacy of benzodiazepines or antipsychotic medications for prevention or treatment of acute cocaine toxicity. The only available controlled data are from animal models and these studies have reported inconsistent benefits. The objective of this study was to quantify the reported efficacy of benzodiazepines and antipsychotic medication for the prevention of mortality due to cocaine poisoning. We conducted a systematic review to identify English language articles describing experiments that compared a benzodiazepine or antipsychotic medication to placebo for the prevention of acute cocaine toxicity in an animal model. We then used these articles in a meta-analysis with a random-effects model to quantify the absolute risk reduction observed in these experiments. We found 10 articles evaluating antipsychotic medications and 15 articles evaluating benzodiazepines. Antipsychotic medications reduced the risk of death by 27% (95% CI, 15.2%-38.7%) compared to placebo and benzodiazepines reduced the risk of death by 52% (42.8%-60.7%) compared to placebo. Both treatments showed evidence of a dose-response effect, and no experiment found a statistically significant increase in risk of death. We conclude that both benzodiazepines and antipsychotic medications are effective for the prevention of lethality from cocaine toxicity in animal models.

  17. Dependence and withdrawal reactions to benzodiazepines and selective serotonin reuptake inhibitors. How did the health authorities react?

    DEFF Research Database (Denmark)

    Nielsen, Margrethe; Hansen, Ebba Holme; Gøtzsche, Peter C

    2013-01-01

    Our objective was to explore communications from drug agencies about benzodiazepine dependence and selective serotonin reuptake inhibitors (SSRIs) withdrawal reactions over time.......Our objective was to explore communications from drug agencies about benzodiazepine dependence and selective serotonin reuptake inhibitors (SSRIs) withdrawal reactions over time....

  18. Does tailoring really make a difference? : the development and evaluation of tailored interventions aimed at benzodiazepine cessation

    NARCIS (Netherlands)

    Wolde, Geeske Brecht ten

    2008-01-01

    Because of the problems associated with chronic benzodiazepine use, there is impetus to prevent and reduce chronic benzodiazepine use. The overall aim was to develop a 'tailor-made' intervention in order to reduce chronic use. Before developing tailored patient education, it is first of all

  19. The effects of benzodiazepine-receptor antagonists and partial inverse agonists on acute hepatic encephalopathy in the rat

    NARCIS (Netherlands)

    Bosman, D. K.; van den Buijs, C. A.; de Haan, J. G.; Maas, M. A.; Chamuleau, R. A.

    1991-01-01

    Two benzodiazepine-receptor partial inverse agonists (Ro 15-4513, Ro 15-3505) and one benzodiazepine-receptor antagonist (flumazenil) were administered to rats with hepatic encephalopathy due to acute liver ischemia. Significant improvement (P less than 0.002) of both the clinical grade of hepatic

  20. ACUTE POISONING WITH BENZODIAZEPINES AND OTHER HYPNOTICS: ETIOLOGIC CAUSE, SEX/AGE DISTRIBUTION AND CLINICAL OUTCOME

    Directory of Open Access Journals (Sweden)

    Petko Marinov

    2016-11-01

    Full Text Available Purpose: Poisoning with drugs occupies a leading position among the causes of acute intoxications. Etiological distribution of medicated poisoning in different countries, even if they are adjacent, is different. In the most studies it was reported that the highest incidence of poisoning is with benzodiazepines or other psychoactive drugs. A retrospective analysis of acute poisoning with benzodiazepines and other hypnotic drugs in the Varna region for 25 years period – from 1991 to 2015 was carried out. Material and Methods: The number of patients who received hospital treatment after poisoning with benzodiazepines is 1741, and those with other hypnotics is 293, representing respectively 26.37% and 4.44% of all drug intoxications. Results: The share of poisoning with benzodiazepines and hypnotics compared to all acute intoxications is 11.66%. They are more common in women – 1566 (77%. Men are 468 (23%, the ratio of men to women was 3.34:1. The largest number of intoxications is in the age group up to 24 years - 1123 (55.2%, and only 4.1% of patients over 60 years. Intentional suicide attempts are 1896 (93.2%. Death is registered in 8 (0.4% patients.

  1. Reduced parahippocampal and lateral temporal GABAA-[11C]flumazenil binding in major depression: preliminary results

    International Nuclear Information System (INIS)

    Klumpers, Ursula M.H.; Veltman, Dick J.; Drent, Madeleine L.; Boellaard, Ronald; Lammertsma, Adriaan A.; Comans, Emile F.I.; Meynen, Gerben; Hoogendijk, Witte J.G.

    2010-01-01

    Major depressive disorder (MDD) has been related to both a dysfunctional γ-amino butyric acid (GABA) system and to hyperactivity of the hypothalamic-pituitary-adrenal axis (HPA). Although GABA has been suggested to inhibit HPA axis activity, their relationship has never been studied at the level of the central GABA A -benzodiazepine receptor in depressed patients or in relation to antidepressant treatment. Eleven depressed outpatients were compared, before and after treatment with citalopram, with nine age-matched healthy controls. The subjects were scanned using the positron emission tomography (PET) tracer [ 11 C]flumazenil ([ 11 C]FMZ). Parametric voxel-by-voxel Logan plots were compared with methods based on regions of interest (ROI), to provide volume of distribution (V T ) and binding potential (BP ND ) values. Plasma GABA levels were determined and a dexamethasone-corticotropin releasing hormone (DEX-CRH) test was performed. In MDD, parametric voxel-by-voxel Logan plots showed bilateral reduced [ 11 C]FMZ binding in the parahippocampal gyrus and right lateral superior temporal gyrus (p uncorrected ≤0.001). In the temporal area, [ 11 C]FMZ binding showed a strong inverse correlation with HPA axis activity. Plasma GABA did not discriminate MDD from controls, but correlated inversely with [ 11 C]FMZ binding in the right insula. Following treatment with citalopram, voxel-based analysis revealed reduced binding in the right lateral temporal gyrus and dorsolateral prefrontal cortex. The bilateral reduction in limbic parahippocampal and right temporal [ 11 C]FMZ binding found in MDD indicates decreased GABA A -benzodiazepine receptor complex affinity and/or number. The inverse relationship between GABA A binding in the temporal lobe and HPA axis activity, suggests that HPA axis hyperactivity is partly due to reduced GABA-ergic inhibition. (orig.)

  2. Micellar Liquid Chromatography for the Determination of Some Less Prescribed Benzodiazepines

    Directory of Open Access Journals (Sweden)

    Hoonka Subhra

    2012-01-01

    Full Text Available A simple chromatographic procedure is reported for the determination of some less prescribed but equally important benzodiazepines (Clotiazepam, clozapine and pinazepam in serum. The optimization studies have been made in CN, C18 and C8 columns, using mobile phase containing sodium dodecyl sulphate (SDS modified with either propanol, butanol or pentanol. The method proposed for the determination of the three benzodiazepines using a mobile phase of 0.13 M SDS, 2.4% pentanol-0.01 M phosphate buffer- 0.1% triethylamine (pH 7 at 25°C and UV detection (240 nm in a C8 column. The serum samples was injected directly, without any pretreatment, eluted in less than 8 min, in accordance to their relative polarities, as indicated by their octanol-water partition coefficients. The limits of detection (ng/mL was in the 1.6 to 5.6 and 7 to 87 range, for aqueous and serum samples, respectively. Repeatability and intermediate precision was tested for three different concentrations of the drugs, resulting in the 0.1 to 2 range. The results obtained here for the separation of the three benzodiazepines in serum were also counter checked at Department of Bio-analytical Chemistry, Universitat Jaume I, Castelló, Spain.

  3. High-dose benzodiazepine dependence: a qualitative study of patients' perception on cessation and withdrawal.

    Science.gov (United States)

    Liebrenz, Michael; Gehring, Marie-Therese; Buadze, Anna; Caflisch, Carlo

    2015-05-13

    Benzodiazepine withdrawal syndrome has been reported following attempts to withdraw even from low or therapeutic doses and has been compared to barbiturate and alcohol withdrawal. This experience is known to deter patients from future cessation attempts. Research on other psychotropic substances shows that the reasons and motivations for withdrawal attempts - as well as the experiences surrounding those attempts - at least partially predict future efforts at discontinuation as well as relapse. We therefore aimed to qualitatively explore what motivates patients to discontinue this medication as well as to examine their experiences surrounding previous and current withdrawal attempts and treatment interventions in order to positively influence future help-seeking behavior and compliance. To understand these patients better, we conducted a series of 41 unstructured, narrative, in-depth interviews among adult Swiss patients with a long-term dependent use of benzodiazepines in doses equivalent to more than 40 mg diazepam per day and/or otherwise problematic use (mixing benzodiazepines, escalating dosage, recreational use or illegal purchase). Mayring's qualitative content analysis was used to evaluate findings. These high-dose benzodiazepine-dependent patients decision to change consumption patterns were affected by health concerns, the feeling of being addicted and social factors. Discontinuation attempts were frequent and not very successful with fast relapse. Withdrawal was perceived to be a difficult, complicated, and highly unpredictable process. The first attempt at withdrawal occurred at home and typically felt better than at the clinic. Inpatient treatment was believed to be more effective with long term treatment (approaches) than short term. Patients preferred gradual reduction of usage to abrupt cessation (and had experienced both). While no clear preferences for withdrawal were found for benzodiazepines with specific pharmacokinetic properties, participants

  4. Altered SPECT 123I-iomazenil Binding in the Cingulate Cortex of Children with Anorexia Nervosa

    Science.gov (United States)

    Nagamitsu, Shinichiro; Sakurai, Rieko; Matsuoka, Michiko; Chiba, Hiromi; Ozono, Shuichi; Tanigawa, Hitoshi; Yamashita, Yushiro; Kaida, Hayato; Ishibashi, Masatoshi; Kakuma, Tatsuki; Croarkin, Paul E.; Matsuishi, Toyojiro

    2016-01-01

    Several lines of evidence suggest that anxiety plays a key role in the development and maintenance of anorexia nervosa (AN) in children. The purpose of this study was to examine cortical GABA(A)-benzodiazepine receptor binding before and after treatment in children beginning intensive AN treatment. Brain single-photon emission computed tomography (SPECT) measurements using 123I-iomazenil, which binds to GABA(A)-benzodiazepine receptors, was performed in 26 participants with AN who were enrolled in a multimodal treatment program. Sixteen of the 26 participants underwent a repeat SPECT scan immediately before discharge at conclusion of the intensive treatment program. Eating behavior and mood disturbances were assessed using Eating Attitudes Test with 26 items (EAT-26) and the short form of the Profile of Mood States (POMS). Clinical outcome scores were evaluated after a 1-year period. We examined association between relative iomazenil-binding activity in cortical regions of interest and psychometric profiles and determined which psychometric profiles show interaction effects with brain regions. Further, we determined if binding activity could predict clinical outcome and treatment changes. Higher EAT-26 scores were significantly associated with lower iomazenil-binding activity in the anterior and posterior cingulate cortex. Higher POMS subscale scores were significantly associated with lower iomazenil-binding activity in the left frontal, parietal cortex, and posterior cingulate cortex (PCC). “Depression–Dejection” and “Confusion” POMS subscale scores, and total POMS score showed interaction effects with brain regions in iomazenil-binding activity. Decreased binding in the anterior cingulate cortex and left parietal cortex was associated with poor clinical outcomes. Relative binding increases throughout the PCC and occipital gyrus were observed after weight gain in children with AN. These findings suggest that cortical GABAergic receptor binding is altered

  5. Characterizing the Interrelationships of Prescription Opioid and Benzodiazepine Drugs With Worker Health and Workplace Hazards.

    Science.gov (United States)

    Kowalski-McGraw, Michele; Green-McKenzie, Judith; Pandalai, Sudha P; Schulte, Paul A

    2017-11-01

    Prescription opioid and benzodiazepine drug use, which has risen significantly, can affect worker health. Exploration of the scientific literature assessed (1) interrelationships of such drug use, occupational risk factors, and illness and injury, and (2) occupational and personal risk factor combinations that can affect their use. The scientific literature from 2000 to 2015 was searched to determine any interrelationships. Evidence for eight conceptual models emerged based on the search yield of 133 articles. These models summarize interrelationships among prescription opioid and benzodiazepine use with occupational injury and illness. Factors associated with the use of these drugs included fatigue, impaired cognition, falls, motor vehicle crashes, and the use of multiple providers. Prescription opioid and benzodiazepine drugs may be both a personal risk factor for work-related injury and a consequence of workplace exposures.

  6. Binding properties of Clostridium botulinum type C progenitor toxin to mucins.

    Science.gov (United States)

    Nakamura, Toshio; Takada, Noriko; Tonozuka, Takashi; Sakano, Yoshiyuki; Oguma, Keiji; Nishikawa, Atsushi

    2007-04-01

    It has been reported that Clostridium botulinum type C 16S progenitor toxin (C16S toxin) first binds to the sialic acid on the cell surface of mucin before invading cells [A. Nishikawa, N. Uotsu, H. Arimitsu, J.C. Lee, Y. Miura, Y. Fujinaga, H. Nakada, T. Watanabe, T. Ohyama, Y. Sakano, K. Oguma, The receptor and transporter for internalization of Clostridium botulinum type C progenitor toxin into HT-29 cells, Biochem. Biophys. Res. Commun. 319 (2004) 327-333]. In this study we investigated the binding properties of the C16S toxin to glycoproteins. Although the toxin bound to membrane blotted mucin derived from the bovine submaxillary gland (BSM), which contains a lot of sialyl oligosaccharides, it did not bind to neuraminidase-treated BSM. The binding of the toxin to BSM was inhibited by N-acetylneuraminic acid, N-glycolylneuraminic acid, and sialyl oligosaccharides strongly, but was not inhibited by neutral oligosaccharides. Both sialyl alpha2-3 lactose and sialyl alpha2-6 lactose prevented binding similarly. On the other hand, the toxin also bound well to porcine gastric mucin. In this case, neutral oligosaccharides might play an important role as ligand, since galactose and lactose inhibited binding. These results suggest that the toxin is capable of recognizing a wide variety of oligosaccharide structures.

  7. Pharmacologically induced long QT type 2 can be rescued by activation of IKs with benzodiazepine R-L3 in isolated guinea pig cardiomyocytes

    DEFF Research Database (Denmark)

    Nissen, Jakob Dahl; Diness, Jonas Goldin; Diness, Thomas Goldin

    2009-01-01

    of this study was to evaluate potential antiarrhythmic effects of compound induced IKs activation using the benzodiazepine L-364,373 (R-L3). Ventricular myocytes from guinea pigs were isolated and whole-cell current clamping was performed at 35 degrees C. It was found that 1 microM R-L3 significantly reduced...

  8. Phenylboronic acid catalysed synthesis of 1,5-benzodiazepines via ...

    Indian Academy of Sciences (India)

    Phenylboronic acid has been found to be an efficient catalyst for the synthesis of 1,5-benzodiazepine derivatives via cyclocondensation of -phenylenediamine and various ketones in good to excellent yields (82-91%) using acetonitrile as solvent at reflux condition. The remarkable advantages offered by this method are ...

  9. An Organocatalyzed and Ultrasound Accelerated Expeditious Synthetic Route to 1,5-Benzodiazepines under Solvent-Free Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Shinde, Pravin V.; Shingate, Bapurao B.; Shingare, Murlidhar S. [Babasaheb Ambedkar Marathwada University, Aurngabad (India)

    2011-04-15

    In the present work, successful implementation of ultrasound irradiations for the rapid synthesis of 1,5- benzodiazepine derivatives under solvent-free conditions is demonstrated. Use of a novel catalyst i.e. camphor sulphonic acid in combination with ultrasound technique is reported for the first time. Comparative study for the synthesis of 1,5-benzodiazepines using conventional as well as ultrasonication method is discussed.

  10. Drug facilitated sexual assault: detection and stability of benzodiazepines in spiked drinks using gas chromatography-mass spectrometry.

    Directory of Open Access Journals (Sweden)

    Lata Gautam

    Full Text Available Benzodiazepines are detected in a significant number of drug facilitated sexual assaults (DFSA. Whilst blood and urine from the victim are routinely analysed, due to the delay in reporting DFSA cases and the short half lives of most of these drugs in blood and urine, drug detection in such samples is problematic. Consideration of the drinks involved and analysis for drugs may start to address this. Here we have reconstructed the 'spiking' of three benzodiazepines (diazepam, flunitrazepam and temazepam into five drinks, an alcopop (flavoured alcoholic drink, a beer, a white wine, a spirit, and a fruit based non-alcoholic drink (J2O chosen as representative of those drinks commonly used by women in 16-24 year old age group. Using a validated GC-MS method for the simultaneous detection of these drugs in the drinks we have studied the storage stability of the benzodiazepines under two different storage conditions, uncontrolled room temperature and refrigerator (4°C over a 25 day period. All drugs could be detected in all beverages over this time period. Diazepam was found to be stable in all of the beverages, except the J2O, under both storage conditions. Flunitrazepam and temazepam were found not to be stable but were detectable (97% loss of temazepam and 39% loss of flunitrazepam from J2O. The recommendations from this study are that there should be a policy change and that drinks thought to be involved in DFSA cases should be collected and analysed wherever possible to support other evidence types.

  11. Psychological determinants of the intention to educate patients about benzodiazepines

    NARCIS (Netherlands)

    Ten Wolde, Geeske Brecht; Dijkstra, A.; Van Empelen, P.; Neven, A. Knuistingh; Zitman, F. G.

    Objective General practitioners and pharmacists do not properly educate their patients about the disadvantages of benzodiazepines. In order to increase and improve education, this study will investigate which psychological factors (i.e., beliefs, outcome expectation, social norm and self-efficacy)

  12. [Appropriate use of benzodiazepines zolpidem and zopiclone in diseases attended in primary care].

    Science.gov (United States)

    Granados Menéndez, M Isabel; Salinero Fort, Miguel Angel; Palomo Ancillo, Marta; Aliaga Gutiérrez, Laura; García Escalonilla, Carmen; Ortega Orcos, Rebeca

    2006-01-01

    To estimate the proportion of benzodiazepine prescriptions that comply with the guidelines for appropriate prescription. To identify the variables associated with appropriate prescription. Observational, cross-sectional study. Monóvar Health Centre in Area IV, Madrid, Spain. Random sample of 270 active benzodiazepine prescriptions in adult patients from the prescriptions record of the OMI-AP V. 5.0 computer system. The chosen dimensions for appropriate prescription were: a) correct diagnostic indication; b) absence of benzodiazepines with long half-life in the elderly; c) existence of support or monitoring visits; d) overall appropriateness or coexistence of correct diagnostic indications and monitoring visits. Independent variables were recorded in relation to patient, person prescribing and prescription. Diagnostic indication, 75.6%; absence of benzodiazepines with long half-life in the elderly, 79.8%; existence of support visits, 63.3%; overall appropriateness, 53%. Main diagnoses: pure anxiety, 29%; anxiety related to other illness, 18.6%; insomnia, 14.8%; cardiovascular illness, 14.8%; alcohol and drug abuse, 4.5%; osteo-muscular illness, 4.4%; schizophrenia, 4.4%. Most prescribed substances: lorazepam, 27.8%; bromazepam, 23.7%. Average life of prescriptions: 18.58 months. Origins: health centre, 68.5%; out-patient psychiatry, 10%; hospital, 10%. The variable that is most closely associated with overall appropriateness, fitted with the rest of the variables, is out-patient psychiatry prescription (OR, 6.67; 95% CI, 1.92-23.18). The mean duration of the prescriptions infringes all standards. The overall appropriateness or correct coexistence of adequate diagnostic indication with follow-up visits is associated with out-patient Psychiatry prescription.

  13. Phenylboronic acid catalysed synthesis of 1,5-benzodiazepines via ...

    Indian Academy of Sciences (India)

    J. Chem. Sci. Vol. 125, No. 4, July 2013, pp. 745–749. c Indian Academy of Sciences. Phenylboronic acid catalysed synthesis of 1,5-benzodiazepines via cyclocondensation of ... active compounds and gaining great consideration in the field of .... thesis of this heterocycles was accomplished by con- densation reaction of ...

  14. Effects of protein restriction, melatonin administration, and short daylength on brain benzodiazepine receptors in prepubertal male rats

    International Nuclear Information System (INIS)

    Kennaway, D.J.; Royles, P.; Webb, H.; Carbone, F.

    1988-01-01

    The possibility that there are changes in brain benzodiazepine binding sites controlled by photoperiod was investigated in two strains of male rats. The hypothesis was tested by 3H-diazepam binding studies in various brain regions of prepubertal rats maintained in 14 or 10 h of light or treated with late-afternoon injections of melatonin (50 micrograms/day). Protein restriction was applied during the experiment to sensitize the animals to the treatments. Under the conditions employed, rats kept in short daylength throughout or kept on long photoperiod and given late-afternoon melatonin injections showed evidence of delayed puberty (seminal vesicle, ventral prostate, and testis weight decreased by 45%, 55%, and 60% respectively, compared to control rats). Binding measurements were made 1 h before and 2 and 5 h after the onset of darkness in the pubertal (42-day-old) or experimentally prepubertal rats. In the rats of the Porton strain (for which protein restriction was obligatory for the gonadal response) there was no consistent treatment or time effects on specific binding of 3H-diazepam to washed membranes of the hypothalamus, midbrain, or striatum. Similarly, there were no differences in the stimulation of 3H-diazepam binding by 100 microM GABA or the inhibition of binding by 50 microM N-acetyl 5 methoxy kynurenamine. By contrast, in Wistar rats, specific binding to midbrain membranes was reduced 5 h after dark compared to 2 h (37% saline; 20% melatonin) and the extent of stimulation by GABA in the hypothalamus was increased 5 h after darkness (35.6% to 46.7% saline; 37.4% to 50% melatonin). Melatonin treatment resulted in significantly higher specific binding in the hypothalamus 2 h after dark (10%, control fed; 20%, protein restricted) but reduced the GABA induced stimulation of binding in the midbrain (35.5% to 25%, control fed; 33.7% to 23.5%, protein restricted)

  15. Sex Hormone–Binding Globulin and Risk of Type 2 Diabetes in Women and Men

    Science.gov (United States)

    Ding, Eric L.; Song, Yiqing; Manson, JoAnn E.; Hunter, David J.; Lee, Cathy C.; Rifai, Nader; Buring, Julie E.; Gaziano, J. Michael; Liu, Simin

    2009-01-01

    BACKGROUND Circulating sex hormone–binding globulin levels are inversely associated with insulin resistance, but whether these levels can predict the risk of developing type 2 diabetes is uncertain. METHODS We performed a nested case–control study of postmenopausal women in the Women’s Health Study who were not using hormone therapy (359 with newly diagnosed type 2 diabetes and 359 controls). Plasma levels of sex hormone–binding globulin were measured; two polymorphisms of the gene encoding sex hormone–binding globulin, SHBG, that were robustly associated with the protein levels were genotyped and applied in mendelian randomization analyses. We then conducted a replication study in an independent cohort of men from the Physicians’ Health Study II (170 with newly diagnosed type 2 diabetes and 170 controls). RESULTS Among women, higher plasma levels of sex hormone–binding globulin were prospectively associated with a lower risk of type 2 diabetes: multivariable odds ratios were 1.00 for the first (lowest) quartile of plasma levels, 0.16 (95% confidence interval [CI], 0.08 to 0.33) for the second quartile, 0.04 (95% CI, 0.01 to 0.12) for the third quartile, and 0.09 (95% CI, 0.03 to 0.21) for the fourth (highest) quartile (P<0.001 for trend). These prospective associations were replicated among men (odds ratio for the highest quartile of plasma levels vs. the lowest quartile, 0.10; 95% CI, 0.03 to 0.36; P<0.001 for trend). As compared with homozygotes of the respective wild-type allele, carriers of a variant allele of the SHBG single-nucleotide polymorphism (SNP) rs6259 had 10% higher sex hormone–binding globulin levels (P = 0.005), and carriers of an rs6257 variant had 10% lower plasma levels (P = 0.004); variants of both SNPs were also associated with a risk of type 2 diabetes in directions corresponding to their associated sex hormone–binding globulin levels. In mendelian randomization analyses, the predicted odds ratio of type 2 diabetes per

  16. Prolonged-release melatonin versus placebo for benzodiazepine discontinuation in patients with schizophrenia: a randomized clinical trial - the SMART trial protocol

    Directory of Open Access Journals (Sweden)

    Oranje Bob

    2011-10-01

    Full Text Available Abstract Background Treatment of schizophrenia frequently includes prolonged benzodiazepine administration despite a lack of evidence of its use. It is often difficult to discontinue benzodiazepines because of the development of dependence. We aim to assess if melatonin can facilitate the withdrawal of prolonged benzodiazepine administration in patients with schizophrenia. Furthermore, we aim to investigate the association of benzodiazepine dose reduction with the following clinically important variables: sleep, psychophysiology, cognition, social function, and quality of life. Methods/Design Randomized, blinded, two-armed, parallel superiority trial. We plan to include 80 consenting outpatients diagnosed with schizophrenia or schizoaffective disorder, 18-55 years of age, treated with antipsychotic drug(s and at least one benzodiazepine derivative for the last three months before inclusion. Exclusion criteria: currently under treatment for alcohol or drug abuse, aggressive or violent behavior, known mental retardation, pervasive developmental disorder, dementia, epilepsy, terminal illness, severe co morbidity, inability to understand Danish, allergy to melatonin, lactose, starch, gelatin, or talc, hepatic impairment, pregnancy or nursing, or lack of informed consent. After being randomized to prolonged-release melatonin (Circadin® 2 mg daily or matching placebo, participants are required to slowly taper off their benzodiazepine dose. The primary outcome measure is benzodiazepine dose at 6 months follow-up. Secondary outcome measures include sleep, psychophysiological, and neurocognitive measures. Data are collected at baseline and at 6 months follow-up regarding medical treatment, cognition, psychophysiology, sleep, laboratory tests, adverse events, psychopathology, social function, and quality of life. Data on medical treatment, cognition, psychophysiology, adverse events, social function, and quality of life are also collected at 2 and 4

  17. Midazolam inhibits chondrogenesis via peripheral benzodiazepine receptor in human mesenchymal stem cells.

    Science.gov (United States)

    Chen, Yung-Ching; Wu, King-Chuen; Huang, Bu-Miin; So, Edmund Cheung; Wang, Yang-Kao

    2018-05-01

    Midazolam, a benzodiazepine derivative, is widely used for sedation and surgery. However, previous studies have demonstrated that Midazolam is associated with increased risks of congenital malformations, such as dwarfism, when used during early pregnancy. Recent studies have also demonstrated that Midazolam suppresses osteogenesis of mesenchymal stem cells (MSCs). Given that hypertrophic chondrocytes can differentiate into osteoblast and osteocytes and contribute to endochondral bone formation, the effect of Midazolam on chondrogenesis remains unclear. In this study, we applied a human MSC line, the KP cell, to serve as an in vitro model to study the effect of Midazolam on chondrogenesis. We first successfully established an in vitro chondrogenic model in a micromass culture or a 2D high-density culture performed with TGF-β-driven chondrogenic induction medium. Treatment of the Midazolam dose-dependently inhibited chondrogenesis, examined using Alcian blue-stained glycosaminoglycans and the expression of chondrogenic markers, such as SOX9 and type II collagen. Inhibition of Midazolam by peripheral benzodiazepine receptor (PBR) antagonist PK11195 or small interfering RNA rescued the inhibitory effects of Midazolam on chondrogenesis. In addition, Midazolam suppressed transforming growth factor-β-induced Smad3 phosphorylation, and this inhibitory effect could be rescued using PBR antagonist PK11195. This study provides a possible explanation for Midazolam-induced congenital malformations of the musculoskeletal system through PBR. © 2018 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  18. Alterations in in-vivo benzodiazepine-receptor binding of C-11-Ro15-1788 (flumazepil)

    International Nuclear Information System (INIS)

    Yamasaki, T.; Inoue, O.; Shinoto, H.; Ito, T.; Hashimoto, K.; Suzuki, K.; Tateno, Y.

    1985-01-01

    Alterations of the central benzodiazepine - receptor function caused by the change of physiological or psychological conditions, were recognized in both animal and human studies. Before the human study, animal experiments using tritiated Ro15-1788 were carried out. The stress was produced by forcing the mice to swim in a water-basin at 16 0 C for 5 min. Within 3 min after the forced swimming, the tracer was injected. Brain radioactivities in stress-loaded mice increased over a period of 15 min after the intra-venous injection of tracers, while brain activities of carrier-added tracer decreased. In human study, approximately 5 mCi of C-11-Ro15-1788, which specific activity is 0.3-1.0 Ci/μmol, were intravenously injected to each case. Measurements of the brain activity were performed using positron-CT, with blood sample collection. 31 human studies were performed on. Cerebral cortex time activity curves in several volunteers in nervous and stressful state, showed the same pattern to that in the stress-loaded animal experiment. It is important that the significant different time course of cerebral activity after the injection of labelled Ro15-1788, was observed in stressful state, compared with control, in both human and animal study. From these results, it will be concluded the positron CT study using /sup 11/C-Ro15-1788 will become a new technic to detect the change of psychological conditions in human brain and to diagnose some kind of neuropsychiatric disease

  19. Impulsivity in men with prescription of benzodiazepines and methadone in prison.

    Science.gov (United States)

    Moreno-Ramos, Luis; Fernández-Serrano, María José; Pérez-García, Miguel; Verdejo-García, Antonio

    2016-06-14

    Benzodiazepines and methadone use has been associated with various neuropsychological impairments. However, to the best of our knowledge, no studies have been carried out on the effect of these substances (either separately or combined) on impulsive personality, including studies in prisoners. The aim of this study is to examine the impulsive personality of a sample of 134 male prisoners using the Sensitivity to Punishment and Sensitivity to Reward Questionnaire (Torrubia, Avila, Molto, & Caseras, 2001) and the UPPS-P Scale (Cyders et al., 2007). Some of these were methadone users, methadone and benzodiazepines users, polydrug users in abstinence and non-dependent drug users. The results showed that drug users have greater sensitivity to reward, positive urgency, negative urgency and sensation seeking than non-dependent users. Methadone users showed more sensitivity to punishment and lack of perseverance with respect to other users. No differences were found between methadone+benzodiazepines users and other groups. The secondary aim is to examine which impulsive personality dimensions are related to the two motivational systems proposed by Gray (BIS-BAS) using exploratory factor analysis. Results showed two different components. One component was defined by the subscales sensitivity to reinforcement, positive urgency, negative urgency and sensation seeking. The second component was defined by the subscales sensitivity to punishment, lack of perseverance and lack of premeditation.

  20. Measurement of specific [3H]-ouabain binding to different types of human leucocytes

    DEFF Research Database (Denmark)

    Boon, Arnold; Oh, V M; Taylor, John E.

    1984-01-01

    We have studied the specific binding of [3H]-ouabain to intact mononuclear leucocytes (82% lymphocytes) and polymorphonuclear leucocytes. In both types of cells [3H]-ouabain binding was saturable, confined to a single site of high affinity, slow to reach equilibrium, slow to reverse, temperature...... were expressed per square micron of cell surface area the difference between the two cell types was proportionately greater (83 and 186 sites per micron 2 respectively). We conclude that the [3H]-ouabain binding sites on mononuclear and polymorphonuclear leucocytes are similar in nature, but different...

  1. Sex differences among recipients of benzodiazepines in Dutch general practice.

    NARCIS (Netherlands)

    Waals, F.W. van der; Mohrs, J.; Foets, M.

    1993-01-01

    Objective: To analyse sex differences among recipients of benzodiazepines in Dutch general practice. Design-Study of consultations and associated interventions as recorded in the Dutch national survey of general practice. Setting: Practices of 45 general practitioners monitored during 1 April to 30

  2. SEX-DIFFERENCES AMONG RECIPIENTS OF BENZODIAZEPINES IN DUTCH GENERAL-PRACTICE

    NARCIS (Netherlands)

    van der Waals, F. W.; Mohrs, J.; Foets, M.

    1993-01-01

    Objective-To analyse sex differences among recipients of benzodiazepines in Dutch general practice. Design-Study of consultations and associated interventions as recorded in the Dutch national survey of general practice. Setting-Practices of 45 general practitioners monitored during 1 April to 30

  3. Rectal benzodiazepines for premedication in children. Review and personal experience.

    Science.gov (United States)

    Govaerts, M J; Capouet, V

    1987-01-01

    Modern anesthetic techniques have modified the aims of premedication in pediatric practice. Anxiolysis, amnesia and easiness of induction are now the the main targets. This paper reviews both the literature and the personal experience of the authors on the subject. Many authors now prefer a benzodiazepine. Rectal instillation of benzodiazepine in solution avoids the trauma of the intramuscular route and produces a faster and more predictable effect, than suppositories. Diazepam (.1 to .2 mg/kg) and flunitrazepam (40 to 80 micrograms/kg) have been extensively used in this indication. Diazepam's duration of elimination being much longer than that of flunitrazepam, this last drug is preferred by many pediatric anesthetists. Midazolam (.4 to .5 mg/kg) has a much faster onset and shorter duration of action. It should thus be preferred if the environment enables the administration of premedication within 10 to 15 minutes of induction.

  4. Porcine circovirus type 2 ORF4 protein binds heavy chain ferritin

    Indian Academy of Sciences (India)

    Porcine circovirus type 2 ORF4 protein binds heavy chain ferritin. Qizhuang Lv Kangkang Guo Tao Wang ... Keywords. Cellular protein; FHC; ORF4 protein; porcine circovirus type 2 (PCV2); yeast two-hybrid ... Journal of Biosciences | News ...

  5. Benzodiazepine receptor and cerebral blood flow in early Alzheimer's disease. SPECT study using 123I-Iomazenil and 123I-IMP

    International Nuclear Information System (INIS)

    Kitamura, Shin; Koshi, Yasuhiko; Komiyama, Tasuku; Sakayori, Osamu; Komaba, Yuichi; Ohyama, Masashi; Mishina, Masahiro; Tsuganesawa, Toshikazu; Terashi, Akiro

    1996-01-01

    This study was designed to investigate benzodiazepine receptors (BZR) and cerebral blood flow (CBF) in patients with early Alzheimer's disease. Imaging of BZR and measurement of CBF were performed by SPECT using 123 I-Iomazenil (IMZ) and 123 I-IMP respectively, in seven patients with early Alzheimer's disease and five patients with unilateral left cerebral infarction as controls. The values for the normal cerebral hemisphere (ratio to the contralateral cerebellum) in patients with cerebral infarction were adopted as control values. In patients with Alzheimer's disease, the CBF (ratio to cerebellum) decreased significantly in the frontal cortex and the parietal cortex compared with the control values. There was no significant difference in late IMZ SPECT counts (ratio to cerebellum) and washout (the ratio of late-to-early IMZ SPECT counts) between patients with Alzheimer's disease and the controls. However, the late IMZ SPECT counts and washout decreased in one patient with moderate dementia. There was a significant correlation between the severity of dementia and the late IMZ SPECT counts in the temporal cortex and the parietal cortex. These results suggest that benzodiazepine binding sites are relatively well preserved in patients with early Alzheimer's disease, and reduction of the CBF is caused by neuronal dysfunction rather than by neuronal loss. IMZ SPECT study is useful and necessary for clarifying the pathophysiological state in Alzheimer's disease. (author)

  6. Further characterization of benzodiazepine receptor differences in long-sleep and short-sleep mice

    International Nuclear Information System (INIS)

    Marley, R.J.; Stinchcomb, A.; Wehner, J.M.

    1988-01-01

    Molecular and conformational characteristics of benzodiazepine (BZ) receptors in cortex and cerebellum from long-sleep and mice were investigated using heat inactivation and beta-carboline competition techniques. To investigate differences in the allosteric coupling between GABA and BZ receptors, the protection of BZ receptors from heat inactivation, by GABA, was also evaluated. The two genotypes do not differ in the affinity or number of BZ receptors in the cortex or cerebellum. They do, however, appear to differ in the molecular structure and/or regulation of the conformational state of the receptor in the cortex, as indicated by a greater sensitivity of LS mice to both heat inactivation and beta-carboline competition of 3 H-flunitrazepam (FNZ) binding in this region. Evidence for differences in the nature of coupling between GABA and BZ receptors is provided by the finding in that in both regions, GABA protected BZ receptors from inactivation to a greater degree in LS mice. The relationship between these differences and the multiplicity of expression of BZ receptors is discussed

  7. Oral Pre-anaesthetic Medication with a New Benzodiazepine Hypnotic

    African Journals Online (AJOL)

    A new benzodiazepine derivative (Ro 5-4200) was used as a hypnotic in a pilot study on 30 patients the night before an operation. The dosage used was 2 mg (1 tablet). Results proved very encouraging, and it was then decided to conduct a controlled double-blind trial comparing Ro 5-4200, phenobarbital 100 mg and a ...

  8. Oral Pre-anaesthetic Medication with a New Benzodiazepine Hypnotic

    African Journals Online (AJOL)

    1973-01-20

    Jan 20, 1973 ... A new benzodiazepine derivative (Ro 5-4200) was used as a hypnotic in a pilot study on 30 patients the night before an operation. The dosage used was 2 mg (1 tablet). Results proved very encouraging, and it was then decided to conduct a controlled double-blind trial com- paring Ro 5-4200, ...

  9. Sex and estrous cycle-dependent changes in neurosteroid and benzodiazepine effects on food consumption and plus-maze learning behaviors in rats.

    Science.gov (United States)

    Reddy, D S; Kulkarni, S K

    1999-01-01

    Experiments were designed to investigate the influence of estrous cycle and gender of the rat on the effects of a gamma-aminobutyric acid type A (GABA(A)) receptor active neurosteroid, 3alpha-hydroxy-5alpha-pregnan-20-one (allopregnanolone), the benzodiazepine, triazolam, and a GABA(A) receptor antagonistic neurosteroid, delta5-androsten-3beta-ol-17-one sulfate (dehydroepiandrosterone sulfate), on food intake and elevated plus-maze learning behaviors. Allopregnanolone (0.25 mg/kg, s.c.) and triazolam (0.25 mg/kg, i.p.) produced a hyperphagic effect, while dehydroepiandrosterone sulfate (5 mg/kg, s.c.) elicited an anorectic effect. However, allopregnanolone was more potent in diestrous females, whereas triazolam exhibited significantly higher hyperphagic potency in estrus females. The extent of anorexia following dehydroepiandrosterone sulfate was alike in male and female rats. The triazolam- and allopregnanolone-induced hyperphagic effect was blocked by bicuculline (1 mg/kg, i.p.), a selective GABA(A) receptor antagonist. In contrast to triazolam, the hyperphagic effect of allopregnanolone was insensitive to flumazenil (5 mg/kg, i.p.), a benzodiazepine antagonist. Vehicle-treated diestrous rats displayed moderately higher latencies in the elevated plus-maze learning task than estrus or proestrus females. Although allopregnanolone and triazolam elicited equipotent learning deficits in plus-maze learning in male and female rats, the magnitude of impairment-induced by triazolam was significantly higher in diestrous females than proestrus females. Dehydroepiandrosterone sulfate enhanced memory performance only in male rats. Although the use of the elevated plus-maze as a learning paradigm with benzodiazepines and neurosteroids may be sensitive to changes in anxiety, the differential data suggest that neurosteroid-induced effects are at least partly specific to learning behavior. These results confirm the role of estrous cycle and sex of rats in modifying the potency of

  10. Urinary liver-type fatty acid-binding protein predicts progression to nephropathy in type 1 diabetic patients

    DEFF Research Database (Denmark)

    Nielsen, Stine Elkjaer; Sugaya, Takeshi; Hovind, Peter

    2010-01-01

    Urinary liver-type fatty acid-binding protein (u-LFABP) is a marker of tubulointerstitial inflammation and has been shown to be increased in patients with type 1 diabetes and is further increased in patients who progress to micro- and macroalbuminuria. Our aim was to evaluate u-LFABP as a predictor...... of progression to micro- and macroalbuminuria in type 1 diabetes....

  11. Reduced parahippocampal and lateral temporal GABA{sub A}-[{sup 11}C]flumazenil binding in major depression: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Klumpers, Ursula M.H. [VU University Medical Center, Department of Psychiatry, Amsterdam (Netherlands); GGZ inGeest, partner of VUmc, Department of Psychiatry, Amsterdam (Netherlands); VU University Medical Center, Neuroscience Campus Amsterdam, Amsterdam (Netherlands); Veltman, Dick J. [VU University Medical Center, Department of Psychiatry, Amsterdam (Netherlands); VU University Medical Center, Neuroscience Campus Amsterdam, Amsterdam (Netherlands); Drent, Madeleine L. [VU University Medical Center, Department of Endocrinology, Amsterdam (Netherlands); Boellaard, Ronald; Lammertsma, Adriaan A. [VU University Medical Center, Department of Nuclear Medicine and PET Research, Amsterdam (Netherlands); VU University Medical Center, Neuroscience Campus Amsterdam, Amsterdam (Netherlands); Comans, Emile F.I. [VU University Medical Center, Department of Nuclear Medicine and PET Research, Amsterdam (Netherlands); Meynen, Gerben [VU University Medical Center, Department of Psychiatry, Amsterdam (Netherlands); Hoogendijk, Witte J.G. [VU University Medical Center, Department of Psychiatry, Amsterdam (Netherlands); VU University Medical Center, Center for Neurogenomics and Cognitive Research, Amsterdam (Netherlands); VU University Medical Center, Neuroscience Campus Amsterdam, Amsterdam (Netherlands)

    2010-03-15

    Major depressive disorder (MDD) has been related to both a dysfunctional {gamma}-amino butyric acid (GABA) system and to hyperactivity of the hypothalamic-pituitary-adrenal axis (HPA). Although GABA has been suggested to inhibit HPA axis activity, their relationship has never been studied at the level of the central GABA{sub A}-benzodiazepine receptor in depressed patients or in relation to antidepressant treatment. Eleven depressed outpatients were compared, before and after treatment with citalopram, with nine age-matched healthy controls. The subjects were scanned using the positron emission tomography (PET) tracer [{sup 11}C]flumazenil ([{sup 11}C]FMZ). Parametric voxel-by-voxel Logan plots were compared with methods based on regions of interest (ROI), to provide volume of distribution (V{sub T}) and binding potential (BP{sub ND}) values. Plasma GABA levels were determined and a dexamethasone-corticotropin releasing hormone (DEX-CRH) test was performed. In MDD, parametric voxel-by-voxel Logan plots showed bilateral reduced [{sup 11}C]FMZ binding in the parahippocampal gyrus and right lateral superior temporal gyrus (p uncorrected {<=}0.001). In the temporal area, [{sup 11}C]FMZ binding showed a strong inverse correlation with HPA axis activity. Plasma GABA did not discriminate MDD from controls, but correlated inversely with [{sup 11}C]FMZ binding in the right insula. Following treatment with citalopram, voxel-based analysis revealed reduced binding in the right lateral temporal gyrus and dorsolateral prefrontal cortex. The bilateral reduction in limbic parahippocampal and right temporal [{sup 11}C]FMZ binding found in MDD indicates decreased GABA{sub A}-benzodiazepine receptor complex affinity and/or number. The inverse relationship between GABA{sub A} binding in the temporal lobe and HPA axis activity, suggests that HPA axis hyperactivity is partly due to reduced GABA-ergic inhibition. (orig.)

  12. Characteristics of benzodiazepine receptors in rats differing in predisposition to experimental alcoholism

    International Nuclear Information System (INIS)

    Burov, Yu.V.; Maiskii, A.I.; Yukhananov, R.Yu.

    1986-01-01

    This paper studies the number and affinity of benzodiazepine receptors for diazepam in the cerebral cortex and hippocampus of rats differently predisposed to the development of experimental alcoholism. Ethanol was injected once intraperitoneally, in a dose of 2.5 g/kg. Control animals received the same volume of physiological saline. Bound and free N-methyl-tritium-diazepam were separated by means of GF/B filters. The characteristics of benzodiazepine receptors are shown in rats differing in predisposition to the development of experimental alcoholism and in rats during voluntary chronic alcoholization. It is shown that weakening of functional acitivity of the GABA-benzodiazepam complex in animals predisposed to the development of experimental alcoholism is one of the neurochemical mechanisms of development of the abstinence syndrome

  13. Benzodiazepines II: Waking Up on Sedatives: Providing Optimal Care When Inheriting Benzodiazepine Prescriptions in Transfer Patients

    Directory of Open Access Journals (Sweden)

    Jeffrey Guina

    2018-01-01

    Full Text Available This review discusses risks, benefits, and alternatives in patients already taking benzodiazepines when care transfers to a new clinician. Prescribers have the decision—sometimes mutually agreed-upon and sometimes unilateral—to continue, discontinue, or change treatment. This decision should be made based on evidence-based indications (conditions and timeframes, comorbidities, potential drug-drug interactions, and evidence of adverse effects, misuse, abuse, dependence, or diversion. We discuss management tools involved in continuation (e.g., monitoring symptoms, laboratory testing, prescribing contracts, state prescription databases, stages of change and discontinuation (e.g., tapering, psychotherapeutic interventions, education, handouts, reassurance, medications to assist with discontinuation, and alternative treatments.

  14. Spectroscopic and molecular docking approaches for investigating conformation and binding characteristics of clonazepam with bovine serum albumin (BSA).

    Science.gov (United States)

    Lou, Yan-Yue; Zhou, Kai-Li; Pan, Dong-Qi; Shen, Jia-Le; Shi, Jie-Hua

    2017-02-01

    Clonazepam, a type of benzodiazepine, is a classical drug used to prevent and treat seizures, panic disorder, movement disorder, among others. For further clarifying the distribution of clonazepam in vivo and the pharmacodynamic and pharmacokinetic mechanisms, the binding interaction between clonazepam and bovine serum albumin (BSA) was investigated using ultraviolet spectroscopy (UV), steady-state fluorescence spectroscopy, synchronous fluorescence spectroscopy, three-dimensional (3D) fluorescence spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and molecular docking methods. The results well confirmed that clonazepam bound on the subdomain III A (Site II) of BSA through van der Waals force and hydrogen bonding interaction, and quenched the intrinsic fluorescence of BSA through a static quenching process. The number of binding sites (n) and binding constant (K b ) of clonazepam-BSA complex were about 1 and 7.94×10 4 M -1 at 308K, respectively. The binding process of clonazepam with BSA was spontaneous and enthalpy-driven process due to ΔG 0 T|ΔS 0 | over the studied temperature range. Meanwhile, the binding interaction of clonazepam with BSA resulted in the slight change in the conformation of BSA and the obvious change in the conformation of clonazepam, implying that the flexibility of clonazepam also played an important role in increasing the stability of the clonazepam-BSA complex. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Prolonged-release melatonin versus placebo for benzodiazepine discontinuation in patients with schizophrenia: a randomized clinical trial - the SMART trial protocol

    DEFF Research Database (Denmark)

    Baandrup, Lone; Fagerlund, Birgitte; Jennum, Poul

    2011-01-01

    Treatment of schizophrenia frequently includes prolonged benzodiazepine administration despite a lack of evidence of its use. It is often difficult to discontinue benzodiazepines because of the development of dependence. We aim to assess if melatonin can facilitate the withdrawal of prolonged...

  16. A control study on treatment for benzodiazepine dependence with trazodone

    Directory of Open Access Journals (Sweden)

    ZHANG Hong-ju

    2013-05-01

    Full Text Available Objective To determine the efficacy and safety of trazodone in the treatment of benzodiazepine dependence. Methods Forty insomnia patients who met the Classification and Diagnostic Criteria of Mental Disorders in China Third Edition (CCMD-3 of dependence syndrome due to benzodiazepine were involved in the study. Patients were randomly assigned to trazodone group and placebo group for 3 months. The efficacy were assessed by Withdrawal Symptoms Checklist, Hamilton Anxiety Rating Scale (HAMA and polysomnography (PSG. Adverse events were assessed by Treatment Emergent Symptom Scale (TESS. Results The Withdrawal Symptoms Checklist of trazodone group was significantly lower after 7 d treatment than that of placebo group (P = 0.000, and HAMA score of the trazodone group was also significantly lower after 15 d treatment than that of placebo group (P = 0.000. There were no difference in Withdrawal Symptoms Checklist and HAMA of placebo group before and after treatment. Withdrawal Symptoms Checklist and HAMA of the trazodone group were decreased after treatment (P = 0.000. In comparison with placebo group, sleep parameters of the trazodone, including total sleep time (TST, sleep efficiency (SE, sleep latency (SL and slow wave sleep (SWS time presented improvement after 7 d treatment (P = 0.000, for all. After trazodone treatment, total sleep time, slow wave sleep time, sleep efficiency and sleep latency were improved (P = 0.000, for all. No obvious adverse reaction occurred. There were no significant differences in TESS scores between pre? and post?treatment in both groups (P > 0.05. Conclusion Trazodone is markedly effective and safe in the treatment for benzodiazepine dependence.

  17. Urinary liver-type fatty acid-binding protein predicts progression to nephropathy in type 1 diabetic patients

    DEFF Research Database (Denmark)

    Nielsen, Stine Elkjaer; Sugaya, Takeshi; Hovind, Peter

    2010-01-01

    Urinary liver-type fatty acid-binding protein (u-LFABP) is a marker of tubulointerstitial inflammation and has been shown to be increased in patients with type 1 diabetes and is further increased in patients who progress to micro- and macroalbuminuria. Our aim was to evaluate u-LFABP as a predictor...

  18. GABA receptor imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Doo [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2007-04-15

    GABA is primary an inhibitory neurotransmitter that is localized in inhibitory interneurons. GABA is released from presynaptic terminals and functions by binding to GABA receptors. There are two types of GABA receptors, GABA{sub A}-receptor that allows chloride to pass through a ligand gated ion channel and GABA{sub B}-receptor that uses G-proteins for signaling. The GABA{sub A}-receptor has a GABA binding site as well as a benzodiazepine binding sites, which modulate GABA{sub A}-receptor function. Benzodiazepine GABAA receptor imaging can be accomplished by radiolabeling derivates that activates benzodiazepine binding sites. There has been much research on flumazenil (FMZ) labeled with {sup 11}C-FMZ, a benzodiazepine derivate that is a selective, reversible antagonist to GABAA receptors. Recently, {sup 18}F-fluoroflumazenil (FFMZ) has been developed to overcome {sup 11}C's short half-life. {sup 18}F-FFMZ shows high selective affinity and good pharmacodynamics, and is a promising PET agent with better central benzodiazepine receptor imaging capabilities. In an epileptic focus, because the GABA/benzodiazepine receptor amount is decreased, using '1{sup 1}C-FMZ PET instead of {sup 18}F-FDG, PET, restrict the foci better and may also help find lesions better than high resolution MR. GABA{sub A} receptors are widely distributed in the cerebral cortex, and can be used as an viable neuronal marker. Therefore it can be used as a neuronal cell viability marker in cerebral ischemia. Also, GABA-receptors decrease in areas where neuronal plasticity develops, therefore, GABA imaging can be used to evaluate plasticity. Besides these usages, GABA receptors are related with psychological diseases, especially depression and schizophrenia as well as cerebral palsy, a motor-related disorder, so further in-depth studies are needed for these areas.

  19. GABA receptor imaging

    International Nuclear Information System (INIS)

    Lee, Jong Doo

    2007-01-01

    GABA is primary an inhibitory neurotransmitter that is localized in inhibitory interneurons. GABA is released from presynaptic terminals and functions by binding to GABA receptors. There are two types of GABA receptors, GABA A -receptor that allows chloride to pass through a ligand gated ion channel and GABA B -receptor that uses G-proteins for signaling. The GABA A -receptor has a GABA binding site as well as a benzodiazepine binding sites, which modulate GABA A -receptor function. Benzodiazepine GABAA receptor imaging can be accomplished by radiolabeling derivates that activates benzodiazepine binding sites. There has been much research on flumazenil (FMZ) labeled with 11 C-FMZ, a benzodiazepine derivate that is a selective, reversible antagonist to GABAA receptors. Recently, 18 F-fluoroflumazenil (FFMZ) has been developed to overcome 11 C's short half-life. 18 F-FFMZ shows high selective affinity and good pharmacodynamics, and is a promising PET agent with better central benzodiazepine receptor imaging capabilities. In an epileptic focus, because the GABA/benzodiazepine receptor amount is decreased, using '1 1 C-FMZ PET instead of 18 F-FDG, PET, restrict the foci better and may also help find lesions better than high resolution MR. GABA A receptors are widely distributed in the cerebral cortex, and can be used as an viable neuronal marker. Therefore it can be used as a neuronal cell viability marker in cerebral ischemia. Also, GABA-receptors decrease in areas where neuronal plasticity develops, therefore, GABA imaging can be used to evaluate plasticity. Besides these usages, GABA receptors are related with psychological diseases, especially depression and schizophrenia as well as cerebral palsy, a motor-related disorder, so further in-depth studies are needed for these areas

  20. The mouse beam walking assay offers improved sensitivity over the mouse rotarod in determining motor coordination deficits induced by benzodiazepines.

    Science.gov (United States)

    Stanley, Joanna L; Lincoln, Rachael J; Brown, Terry A; McDonald, Louise M; Dawson, Gerard R; Reynolds, David S

    2005-05-01

    The mouse rotarod test of motor coordination/sedation is commonly used to predict clinical sedation caused by novel drugs. However, past experience suggests that it lacks the desired degree of sensitivity to be predictive of effects in humans. For example, the benzodiazepine, bretazenil, showed little impairment of mouse rotarod performance, but marked sedation in humans. The aim of the present study was to assess whether the mouse beam walking assay demonstrates: (i) an increased sensitivity over the rotarod and (ii) an increased ability to predict clinically sedative doses of benzodiazepines. The study compared the effects of the full benzodiazepine agonists, diazepam and lorazepam, and the partial agonist, bretazenil, on the mouse rotarod and beam walking assays. Diazepam and lorazepam significantly impaired rotarod performance, although relatively high GABA-A receptor occupancy was required (72% and 93%, respectively), whereas beam walking performance was significantly affected at approximately 30% receptor occupancy. Bretazenil produced significant deficits at 90% and 53% receptor occupancy on the rotarod and beam walking assays, respectively. The results suggest that the mouse beam walking assay is a more sensitive tool for determining benzodiazepine-induced motor coordination deficits than the rotarod. Furthermore, the GABA-A receptor occupancy values at which significant deficits were determined in the beam walking assay are comparable with those observed in clinical positron emission tomography studies using sedative doses of benzodiazepines. These data suggest that the beam walking assay may be able to more accurately predict the clinically sedative doses of novel benzodiazepine-like drugs.

  1. Improving the use of benzodiazepines-Is it possible? A non-systematic review of interventions tried in the last 20 years

    Directory of Open Access Journals (Sweden)

    Tett Susan E

    2010-11-01

    Full Text Available Abstract Background Benzodiazepines are often used on a long term basis in the elderly to treat various psychological disorders including sleep disorders, some neurological disorders and anxiety. This is despite the risk of dependence, cognitive impairment, and falls and fractures. Guidelines, campaigns and prescribing restrictions have been used to raise awareness of potentially inappropriate use, however long term use of benzodiazepine and related compounds is currently increasing in Australia and worldwide. The objective of this paper is to explore interventions aimed at improving the prescribing and use of benzodiazepines in the last 20 years. Methods Medline, EMBASE, PsychINFO, IPA were searched for the period 1987 to June 2007. Results Thirty-two articles met the study eligibility criteria (interventions solely focusing on increasing appropriate prescribing and reducing long term use of benzodiazepines and were appraised. Insufficient data were presented in these studies for systematic data aggregation and synthesis, hence critical appraisal was used to tabulate the studies and draw empirical conclusions. Three major intervention approaches were identified; education, audit and feedback, and alerts. Conclusions Studies which used a multi-faceted approach had the largest and most sustained reductions in benzodiazepines use. It appears that support groups for patients, non-voluntary recruitment of GPs, and oral delivery of alerts or feedback may all improve the outcomes of interventions. The choice of outcome measures, delivery style of educational messages, and requests by GPs to stop benzodiazepines, either in a letter or face to face, showed no differences on the success rates of the intervention.

  2. Evaluation of benzodiazepines and zolpidem in nails and their stability after prolonged exposure to chlorinated water.

    Science.gov (United States)

    Moretti, Matteo; Andrello, Luisa; Visonà, Silvia; Vignali, Claudia; Groppi, Angelo; Freni, Francesca; Osculati, Antonio; Tajana, Luca; Morini, Luca

    2018-04-15

    The study aims the development and validation of a LC-MS/MS method for the identification and quantification of benzodiazepines and zolpidem in nails as alternative keratinized matrix to hair in long-term monitoring of anxiolytic and hypnotic drugs. Both fingernail and toenail samples (1-2 mm) were collected by clipping the excess overhang of the nail from volunteers and from postmortem cases. They were washed twice with organic solvents, dried under nitrogen stream, pulverized, immersed in a methanol solution (internal standard: diazepam-D5) and sonicated up to two hours. The solution was then direct injected in the LC-MS/MS system. Mass spectrometry was set in MRM mode, selecting two transitions for each substance. 32 analytes among benzodiazepines, metabolites and hypnotics were included in the list. The method fulfilled the internationally required criteria for validation. Limits of detection ranged from 0.03 pg/mg (zolpidem) to 13.1 pg/mg (bromazepam). 9 subjects under therapy were positive at 7 different benzodiazepines and/or metabolites (lorazepam, desalkylflurazepam, bromazepam, diazepam, alprazolam, lormetazepam and prazepam), while 5 molecules were measured in 4 postmortem cases (diazepam, desmethyldiazepam, delorazepam, 7-aminoclonazepam and zolpidem). In vitro experiments on eight authentic samples suggested that benzodiazepines in nails are influenced by the prolonged exposure to chlorinated water. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Elderly benzodiazepine users at increased risk of activity limitations: influence of chronicity, indications, and duration of action--the three-city cohort.

    Science.gov (United States)

    Carrière, Isabelle; Mura, Thibault; Pérès, Karine; Norton, Joanna; Jaussent, Isabelle; Edjolo, Arlette; Rouaud, Olivier; Berr, Claudine; Ritchie, Karen; Ancelin, Marie Laure

    2015-08-01

    To examine the cross-sectional and longitudinal associations between benzodiazepine use and daily activity limitations, according to drug indications and duration of action. Prospective cohort study. Population-based three-city study. 6,600 participants aged 65 years and over included between 1999 and 2001 and followed after 2, 4, and 7 years. Benzodiazepine users were separated into hypnotic, short-acting anxiolytic, and long-acting anxiolytic users and compared with non users. Three outcomes were examined assessing restrictions in mobility, instrumental activities of daily living (IADLs) and social participation. In multivariate simple or mixed logistic models adjusted for sociodemographic variables, impairments and comorbidity, and for anxiety, insomnia, and depression, hypnotic benzodiazepines were moderately associated with mobility limitation prevalence and IADL limitation incidence. Short-acting and long-acting anxiolytics were associated with IADL limitation prevalence and with mobility limitation prevalence and incidence and long-acting anxiolytics were also associated with IADL limitation incidence. Chronic benzodiazepines users were at a marked risk of developing restrictions for the three outcomes; odds ratio: 1.71 (95% CI: 1.23-2.39) for mobility, 1.54 (95% CI: 1.14-2.10) for IADL, and 1.74 (95% CI: 1.23-2.47) for participation limitations. Benzodiazepine users are at increased risk of activity limitations regardless of the duration of action or indication. Chronic use of benzodiazepines should be avoided in order to extend disability-free survival. Copyright © 2015 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

  4. Analysis of the ligand binding properties of recombinant bovine liver-type fatty acid binding protein

    DEFF Research Database (Denmark)

    Rolf, B; Oudenampsen-Krüger, E; Börchers, T

    1995-01-01

    The coding part of the cDNA for bovine liver-type fatty acid binding protein (L-FABP) has been amplified by RT-PCR, cloned and used for the construction of an Escherichia coli (E. coli) expression system. The recombinant protein made up to 25% of the soluble E. coli proteins and could be isolated...

  5. A Review of the Updated Pharmacophore for the Alpha 5 GABA(A Benzodiazepine Receptor Model

    Directory of Open Access Journals (Sweden)

    Terry Clayton

    2015-01-01

    Full Text Available An updated model of the GABA(A benzodiazepine receptor pharmacophore of the α5-BzR/GABA(A subtype has been constructed prompted by the synthesis of subtype selective ligands in light of the recent developments in both ligand synthesis, behavioral studies, and molecular modeling studies of the binding site itself. A number of BzR/GABA(A α5 subtype selective compounds were synthesized, notably α5-subtype selective inverse agonist PWZ-029 (1 which is active in enhancing cognition in both rodents and primates. In addition, a chiral positive allosteric modulator (PAM, SH-053-2′F-R-CH3 (2, has been shown to reverse the deleterious effects in the MAM-model of schizophrenia as well as alleviate constriction in airway smooth muscle. Presented here is an updated model of the pharmacophore for α5β2γ2 Bz/GABA(A receptors, including a rendering of PWZ-029 docked within the α5-binding pocket showing specific interactions of the molecule with the receptor. Differences in the included volume as compared to α1β2γ2, α2β2γ2, and α3β2γ2 will be illustrated for clarity. These new models enhance the ability to understand structural characteristics of ligands which act as agonists, antagonists, or inverse agonists at the Bz BS of GABA(A receptors.

  6. The influence of cement type and temperature on chloride binding in cement paste

    DEFF Research Database (Denmark)

    Jensen, Ole Mejlhede; Korzen, Migge Sofie Hoffmann; Skibsted, Jørgen

    1998-01-01

    This paper describes effects of cement type and temperature on chloride binding in cement paste, which is an important subject in relation to life-time modelling of reinforced concrete structures. The influence of cement type on chloride binding is investigated by substituting cement with pure...... cement clinker. Both theoretical considerations and experimental data for chloride binding in cement pastes are presented. A physico-chemically based model to describe the influence of temperature on physical binding of chloride is presented. Solid-state 27Al and 29Si magic-angle spinning (MAS) nuclear...... magnetic resonance (NMR) spectroscopy has been used for quantification of the anhydrous and hydrated aluminate and silicate phases in the chloride exposed cement pastes. The 27Al isotropic chemical shift and nuclear quadrupole coupling is reported for a synthetic sample of Friedel's salt, Ca2Al(OH)6Cl×2H2O....

  7. Electrocardiographic Manifestations of Benzodiazepine Toxicity

    Directory of Open Access Journals (Sweden)

    Nahid Kazemzadeh

    2014-11-01

    Full Text Available Background: The aim of this study was to evaluate and compare the clinical and electrocardiographic (ECG manifestations of benzodiazepines (BZs. Methods: In this retrospective study, all BZ-poisoned patients hospitalized at Loghman Hakim Hospital between September 2010 and March 2011 were evaluated. Patients’ information including age, sex, time elapsed between the ingestion and presentation, and type of the BZ used were extracted from the patients' charts and recorded. ECGs on presentation to the emergency department (ED were evaluated and parameters such as PR interval, QRS duration, corrected QT, amplitude of S wave in lead I, height of R wave and R/S ratio in the lead aVR were also measured and recorded. Results: Oxazepam, chlordiazepoxide, lorazepam, alprazolam, diazepam, and clonazepam were ingested by 9 (3%, 13 (4.4%, 29 (9.9%, 105 (35.8%, 65 (22.2%, and 72 (24.6% patients, respectively. Mean PR interval was reported to be 0.16 ± 0.03 sec and PR interval of greater than 200 msec was detected in 12 (4.5% patients. Mean QRS duration was 0.07 ± 0.01sec and QRS≥120 msec was observed in 7 (2.6% cases. Conclusion: Diazepam is the only BZ that does not cause QRS widening and oxazepam is the only one not causing PR prolongation. It can be concluded that if a patient refers with a decreased level of consciousness and accompanying signs of BZ toxicity, QRS widening in ECG rules out diazepam, whereas PR prolongation rules out oxazepam toxicity.

  8. Intramolecular Azide to Alkene Cycloadditions for the Construction of Pyrrolobenzodiazepines and Azetidino-Benzodiazepines

    Czech Academy of Sciences Publication Activity Database

    Hemming, K.; Chambers, Christopher S.; Jamshaid, F.; O´Gorman, Paul A.

    2014-01-01

    Roč. 19, č. 10 (2014), s. 16737-16756 ISSN 1420-3049 Institutional support: RVO:61388971 Keywords : azide * cycloadditions * benzodiazepines Subject RIV: CC - Organic Chemistry Impact factor: 2.416, year: 2014

  9. Determination of benzodiazepines in beverages using green extraction methods and capillary HPLC-UV detection.

    Science.gov (United States)

    Piergiovanni, Maurizio; Cappiello, Achille; Famiglini, Giorgio; Termopoli, Veronica; Palma, Pierangela

    2018-05-30

    Dispersive liquid-liquid microextraction with and without ultrasound assistance (DLLME, UA-DLLME) and microextraction with packed sorbent (MEPS) methods for the extraction and determination of eight different benzodiazepines (BDZ) (chlordiazepoxide, flurazepam, bromazepam, oxazepam, lorazepam, clobazam, clonazepam, and flunitrazepam) in three commercial non-alcoholic and light alcoholic beverages were optimized and compared. Benzodiazepines are frequently used for their extensive diffusion and strong numbing effect in drug-facilitated crimes (DFC). The tiny small amount of sample required for DLLME and MEPS extraction makes them very suitable for specimens collected at the crime scene of DFCs. Microextraction techniques are of increasing interest thanks to their accordance to green analytical chemistry (GAC) guidelines providing good recovery values. Ultrasound assistance (UA-DLLME) was used to investigate whether this type of energy can improve the recoveries of the analytes. Analyses of the extracts were performed with reverse-phase capillary high-performance liquid chromatography with UV detection (HPLC - UV), thanks to low environmental impact, robustness, diffusion, and affordability. Recovery percentages at three different concentrations in the three beverages were between 14.30% and 103.28% with intraday and interday RSD lower than ±2.78%. The same samples were extracted using a MEPS protocol, and the results were compared with those obtained with DLLME. MEPS gave recoveries between 20.90% and 101.88% for all matrices showing a better performance than DLLME at higher concentrations, though lower recoveries were observed with diluted samples. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Prolactin-stimulated mitogenesis in the Nb2 rat lymphoma cell: Lack of protoporphyrin IX effects

    Energy Technology Data Exchange (ETDEWEB)

    Gerrish, K.E.; Putnam, C.W.; Laird, H.E. II (Univ. of Arizona, Tucson (USA))

    1990-01-01

    Pharmacological characterization of the Nb2 cell peripheral-type benzodiazepine receptor (PBR) was determined using selected 1,4-benzodiazepines, PK 11195, and protoporphyrin IX (PPIX) to compete for specific ({sup 3}H) Ro5-4864 binding. These data suggest that PPIX possesses an affinity for the Nb2 cell PBR. We have previously reported that the peripheral benzodiazepine ligands, Ro5-4864 and PK 11195, modulate prolactin-stimulated mitogenesis in the Nb2 cell. In contrast, PPIX, a putative endogenous ligand for the PBR had no effect on prolactin-stimulated mitogenesis in the Nb2 cell over the concentration range from 10{sup {minus}15} M to 10{sup {minus}6} M. Taken together these data show that PPIX has an affinity for the Nb2 cell PBR but does not modulate prolactin-stimulated mitogenesis at concentrations which should bind to the Nb2 cell PBR.

  11. AC-3933, a benzodiazepine partial inverse agonist, improves memory performance in MK-801-induced amnesia mouse model.

    Science.gov (United States)

    Hashimoto, Takashi; Iwamura, Yoshihiro

    2016-05-01

    AC-3933, a novel benzodiazepine receptor partial inverse agonist, is a drug candidate for cognitive disorders including Alzheimer's disease. We have previously reported that AC-3933 enhances acetylcholine release in the rat hippocampus and ameliorates scopolamine-induced memory impairment and age-related cognitive decline in both rats and mice. In this study, we further evaluated the procognitive effect of AC-3933 on memory impairment induced by MK-801, an N-methyl-d-aspartate receptor antagonist, in mice. Unlike the acetylcholinesterase inhibitor donepezil and the benzodiazepine receptor inverse agonist FG-7142, oral administration of AC-3933 significantly ameliorated MK-801-induced memory impairment in the Y-maze test and in the object location test. Interestingly, the procognitive effects of AC-3933 on MK-801-induced memory impairment were not affected by the benzodiazepine receptor antagonist flumazenil, although this was not the case for the beneficial effects of AC-3933 on scopolamine-induced memory deficit. Moreover, the onset of AC-3933 ameliorating effect on scopolamine- or MK-801-induced memory impairment was different in the Y-maze test. Taken together, these results indicate that AC-3933 improves memory deficits caused by both cholinergic and glutamatergic hypofunction and suggest that the ameliorating effect of AC-3933 on MK-801-induced memory impairment is mediated by a mechanism other than inverse activation of the benzodiazepine receptor. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. 125I-iomazenil binding shows stress- and/or diazepam-induced reductions in mouse brain. Supporting data for 123I-iomazenil SPECT study of anxiety disorders

    International Nuclear Information System (INIS)

    Takahashi, Makoto; Odano, Ikuo; Fujita, Shozo; Ohkubo, Masaki.

    1997-01-01

    Effects of repeated swim stress on the binding of 125 I-iomazenil were examined in the brains of diazepam-treated and non-treated mice. The mice were orally administered diazepam or vehicle (0.5% ethylene glycol) and subjected to daily swim stress (at 20degC for 10 min) for seven consecutive days. The distribution and the amount of 125 I-iomazenil binding were analyzed autoradiographically after in vivo and in vitro binding experiments. Repeated swim stress decreased the in vivo binding in the hippocampus (p 125 I-iomazenil binding. These results suggest that we can investigate the pathophysiology of stress and anxiety with 123 I-iomazenil SPECT. Care must be taken concerning the effects of benzodiazepines. (author)

  13. Temperature dependence and GABA modulation of [3H]triazolam binding in the rat brain

    International Nuclear Information System (INIS)

    Earle, M.E.; Concas, A.; Wamsley, J.K.; Yamamura, H.I.

    1987-01-01

    The hypnotic triazolam (TZ), a triazolobenzodiazepine displays a short physiological half life and has been used for the treatment of insomnia related to anxiety states. The authors major objectives were the direct measurement of the temperature dependence and the gamma-aminobutyric acid (GABA) effect of [ 3 H]TZ binding in the rat brain. Saturation studies showed a shift to lower affinity with increasing temperatures (K/sub d/ = 0.27 +/- 08 nM at 0 0 C; K/sub d/ = 1.96 +/- 0.85 nM at 37 0 C) while the B/sub max/ values remained unchanged (1220 +/- 176 fmoles/mg protein at 0 0 C and 1160 +/- 383 fmoles/mg protein at 37 0 C). Saturation studies of [ 3 H]TZ binding in the presence or absence of GABA (100μM) showed a GABA-shift. At 0 0 C the K/sub d/ values were (K/sub d/ = 0.24 +/- 0.03 nM/-GABA; K/sub d/ = 0.16 +/- 0.04/+GABA) and at 37 0 C the K/sub d/ values were (K/sub d/ = 1.84 +/- 0.44 nM/-GABA; K/sub d/ = 0.95 +/- 0.29 nM/+GABA). In contrast to reported literature, the authors findings show that TZ interacts with benzodiazepine receptors with a temperature dependence and GABA-shift consistent with predicted behavior for benzodiazepine agonists. 20 references, 3 tables

  14. Circadian rest-activity rhythms during benzodiazepine tapering covered by melatonin versus placebo add-on: data derived from a randomized clinical trial

    Directory of Open Access Journals (Sweden)

    Lone Baandrup

    2016-10-01

    Full Text Available Abstract Background Patients with severe mental illness often suffer from disruptions in circadian rest-activity cycles, which might partly be attributed to ongoing psychopharmacological medication. Benzodiazepines are frequently prescribed for prolonged periods despite recommendations of only short-term usage. Melatonin, a naturally occurring nocturnal hormone, has the potential to stabilize disrupted circadian rhythmicity. Our aim was to investigate how prolonged-release melatonin affects rest-activity patterns in medicated patients with severe mental illness and if benzodiazepine dose reduction is associated with changes in circadian rhythm parameters. Method Data were derived from a randomized, double-blinded clinical trial with 24 weeks follow-up. Participants were randomized to add-on treatment with prolonged-release melatonin (2 mg or matching placebo, and usual benzodiazepine dosage was gradually tapered. Here we report the results of 72 h of actigraphic assessment of activity-rest cycles performed pre and post tapering. Changes in rest-activity rhythm parameters between the melatonin and placebo group were analyzed using the univariate general linear model. Change in activity counts per 6 h, from baseline to follow-up, in the whole sample was analyzed using paired samples t-test. Results A subsample of 48 patients participated in the actigraphic assessment: 20 in the melatonin group and 28 in the placebo group. Rest-activity cycles varied from regular to highly disrupted. Melatonin significantly increased the interdaily stability and at a trend level decreased the intradaily variability compared with placebo. Benzodiazepine dose reduction was not associated with these circadian rhythm parameters. Activity counts were generally higher after benzodiazepine dose reduction compared with pre tapering, but differences did not reach statistical significance. Conclusion Our data suggest melatonin as an aid during benzodiazepine withdrawal for

  15. Electronic and conformational properties of 2,3-benzodiazepine derivates

    International Nuclear Information System (INIS)

    Pelaggi, M.; Girlanda, R.; Chimirri, A.; Gitto, R.

    1996-01-01

    The molecular geometric and electronic structures of 2,3-benzodiazepine derivates have been studied by means of the MNDO-PM3 method. A number of electronic properties have been computed and examined in order to find indication of the role of the electronic characteristics of the different molecules and their pharmacological properties. Theoretical data indicate that both electronic and structural properties appear responsible for the varying degree of anticonvulsant activity exhibited by compounds 1-4

  16. Electronic and conformational properties of 2,3-benzodiazepine derivates

    Energy Technology Data Exchange (ETDEWEB)

    Pelaggi, M.; Girlanda, R. [Messina Univ. (Italy). Dip. di Fisica della Materia e Fisica dell`Ambiente; Chimirri, A.; Gitto, R. [Messina Univ. (Italy). Dip. Farmaco-Chimico

    1996-04-01

    The molecular geometric and electronic structures of 2,3-benzodiazepine derivates have been studied by means of the MNDO-PM3 method. A number of electronic properties have been computed and examined in order to find indication of the role of the electronic characteristics of the different molecules and their pharmacological properties. Theoretical data indicate that both electronic and structural properties appear responsible for the varying degree of anticonvulsant activity exhibited by compounds 1-4.

  17. GABAA receptor activity modulating piperine analogs: In vitro metabolic stability, metabolite identification, CYP450 reaction phenotyping, and protein binding.

    Science.gov (United States)

    Zabela, Volha; Hettich, Timm; Schlotterbeck, Götz; Wimmer, Laurin; Mihovilovic, Marko D; Guillet, Fabrice; Bouaita, Belkacem; Shevchenko, Bénédicte; Hamburger, Matthias; Oufir, Mouhssin

    2018-01-01

    In a screening of natural products for allosteric modulators of GABA A receptors (γ-aminobutyric acid type A receptor), piperine was identified as a compound targeting a benzodiazepine-independent binding site. Given that piperine is also an activator of TRPV1 (transient receptor potential vanilloid type 1) receptors involved in pain signaling and thermoregulation, a series of piperine analogs were prepared in several cycles of structural optimization, with the aim of separating GABA A and TRPV1 activating properties. We here investigated the metabolism of piperine and selected analogs in view of further cycles of lead optimization. Metabolic stability of the compounds was evaluated by incubation with pooled human liver microsomes, and metabolites were analyzed by UHPLC-Q-TOF-MS. CYP450 isoenzymes involved in metabolism of compounds were identified by reaction phenotyping with Silensomes™. Unbound fraction in whole blood was determined by rapid equilibrium dialysis. Piperine was the metabolically most stable compound. Aliphatic hydroxylation, and N- and O-dealkylation were the major routes of oxidative metabolism. Piperine was exclusively metabolized by CYP1A2, whereas CYP2C9 contributed significantly in the oxidative metabolism of all analogs. Extensive binding to blood constituents was observed for all compounds. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Consequences of early postnatal benzodiazepines exposure in rats. II. Social behavior

    Czech Academy of Sciences Publication Activity Database

    Mikulecká, Anna; Šubrt, Martin; Pařízková, Martina; Mareš, Pavel; Kubová, Hana

    2014-01-01

    Roč. 8, May 8 (2014), s. 169 ISSN 1662-5153 R&D Projects: GA ČR(CZ) GBP304/12/G069; GA ČR(CZ) GA305/09/0846 Institutional support: RVO:67985823 Keywords : benzodiazepines * clonazepam * social behavior * development * rats Subject RIV: FH - Neurology Impact factor: 3.270, year: 2014

  19. Correlates of benzodiazepine dependence in the Netherlands Study of Depression and Anxiety

    NARCIS (Netherlands)

    Manthey, L.; Lohbeck, M.; Giltay, E.J.; van Veena, T.; Zitman, F.G.; Penninx, B.W.J.H.

    2012-01-01

    Aims: Benzodiazepines (BZDs) are effective in the short term against anxiety and insomnia. However, some BZD users develop BZD dependence after a relatively short period of time. Therefore, we aimed to identify the risk factors of BZD dependence. Design: An observational cohort study. Setting: The

  20. Enhanced Human-Type Receptor Binding by Ferret-Transmissible H5N1 with a K193T Mutation.

    Science.gov (United States)

    Peng, Wenjie; Bouwman, Kim M; McBride, Ryan; Grant, Oliver C; Woods, Robert J; Verheije, Monique H; Paulson, James C; de Vries, Robert P

    2018-05-15

    All human influenza pandemics have originated from avian influenza viruses. Although multiple changes are needed for an avian virus to be able to transmit between humans, binding to human-type receptors is essential. Several research groups have reported mutations in H5N1 viruses that exhibit specificity for human-type receptors and promote respiratory droplet transmission between ferrets. Upon detailed analysis, we have found that these mutants exhibit significant differences in fine receptor specificity compared to human H1N1 and H3N2 and retain avian-type receptor binding. We have recently shown that human influenza viruses preferentially bind to α2-6-sialylated branched N-linked glycans, where the sialic acids on each branch can bind to receptor sites on two protomers of the same hemagglutinin (HA) trimer. In this binding mode, the glycan projects over the 190 helix at the top of the receptor-binding pocket, which in H5N1 would create a stearic clash with lysine at position 193. Thus, we hypothesized that a K193T mutation would improve binding to branched N-linked receptors. Indeed, the addition of the K193T mutation to the H5 HA of a respiratory-droplet-transmissible virus dramatically improves both binding to human trachea epithelial cells and specificity for extended α2-6-sialylated N-linked glycans recognized by human influenza viruses. IMPORTANCE Infections by avian H5N1 viruses are associated with a high mortality rate in several species, including humans. Fortunately, H5N1 viruses do not transmit between humans because they do not bind to human-type receptors. In 2012, three seminal papers have shown how these viruses can be engineered to transmit between ferrets, the human model for influenza virus infection. Receptor binding, among others, was changed, and the viruses now bind to human-type receptors. Receptor specificity was still markedly different compared to that of human influenza viruses. Here we report an additional mutation in ferret

  1. Receptor type I and type II binding regions and the peptidyl-prolyl isomerase site of cyclophilin B are required for enhancement of T-lymphocyte adhesion to fibronectin.

    Science.gov (United States)

    Carpentier, Mathieu; Allain, Fabrice; Slomianny, Marie-Christine; Durieux, Sandrine; Vanpouille, Christophe; Haendler, Bernard; Spik, Geneviève

    2002-04-23

    Cyclophilin B (CyPB), a cyclosporin A (CsA) binding protein, interacts with two types of binding sites at the surface of T-lymphocytes. The type I sites correspond to functional receptors involved in endocytosis and the type II sites to sulfated glycosaminoglycans (GAGs). Mutational analysis of CyPB has revealed that W128, which is part of the CsA-binding pocket, is implicated in the binding to the functional type I receptors and that two amino acid clusters located in the N-terminus ensure the binding to GAGs. The peptidyl-prolyl isomerase activity of CyPB is not required for receptor binding. We have recently demonstrated that CyPB enhances adhesion of peripheral blood T-lymphocytes to fibronectin, a component of the extracellular matrix. We intended to identify additional amino acids involved in the binding of CyPB to its functional type I receptor and to determine regions responsible for the stimulation of peripheral blood T-lymphocyte adhesion. We determined that residues R76, G77, K132, D155, and D158 of the calcineurin (CN) interacting region were implicated in the recognition of type I receptor but not of GAGs. We also found that two different changes in the N-terminal extension that abated binding to GAGs prevented adhesion of peripheral blood T-lymphocytes to coated CyPB, whereas abbrogation of the PPIase activity had no effect. On the other hand, the adhesion of peripheral blood T-lymphocytes to coated fibronectin was not stimulated by CyPB mutants devoid of either type I receptor or GAGs binding activity or by mutants of the PPIase site. Altogether, the results demonstrate that different regions of CyPB are involved in peripheral blood T-lymphocyte activation and imply a novel important physiological function for peptidyl-prolyl isomerase activity.

  2. Genetic markers of a Munc13 protein family member, BAIAP3, are gender specifically associated with anxiety and benzodiazepine abuse in mice and humans.

    Science.gov (United States)

    Wojcik, Sonja M; Tantra, Martesa; Stepniak, Beata; Man, Kwun-Nok M; Müller-Ribbe, Katja; Begemann, Martin; Ju, Anes; Papiol, Sergi; Ronnenberg, Anja; Gurvich, Artem; Shin, Yong; Augustin, Iris; Brose, Nils; Ehrenreich, Hannelore

    2013-07-24

    Anxiety disorders and substance abuse, including benzodiazepine use disorder, frequently occur together. Unfortunately, treatment of anxiety disorders still includes benzodiazepines, and patients with an existing comorbid benzodiazepine use disorder or a genetic susceptibility for benzodiazepine use disorder may be at risk of adverse treatment outcomes. The identification of genetic predictors for anxiety disorders, and especially for benzodiazepine use disorder, could aid the selection of the best treatment option and improve clinical outcomes. The brain-specific angiogenesis inhibitor I-associated protein 3 (Baiap3) is a member of the mammalian uncoordinated 13 (Munc13) protein family of synaptic regulators of neurotransmitter exocytosis, with a striking expression pattern in amygdalae, hypothalamus and periaqueductal gray. Deletion of Baiap3 in mice leads to enhanced seizure propensity and increased anxiety, with the latter being more pronounced in female than in male animals. We hypothesized that genetic variation in human BAIAP3 may also be associated with anxiety. By using a phenotype-based genetic association study, we identified two human BAIAP3 single-nucleotide polymorphism risk genotypes (AA for rs2235632, TT for rs1132358) that show a significant association with anxiety in women and, surprisingly, with benzodiazepine abuse in men. Returning to mice, we found that male, but not female, Baiap3 knockout (KO) mice develop tolerance to diazepam more quickly than control animals. Analysis of cultured Baiap3 KO hypothalamus slices revealed an increase in basal network activity and an altered response to diazepam withdrawal. Thus, Baiap3/BAIAP3 is gender specifically associated with anxiety and benzodiazepine use disorder, and the analysis of Baiap3/BAIAP3-related functions may help elucidate mechanisms underlying the development of both disorders.

  3. DNA binding properties of dioxin receptors in wild-type and mutant mouse hepatoma cells

    International Nuclear Information System (INIS)

    Cuthill, S.; Poellinger, L.

    1988-01-01

    The current model of action of 2,3,7,8-tetrachlorodibenzo-p-dioxin (dioxin) entails stimulation of target gene transcription via the formation of dioxin-receptor complexes and subsequent accumulation of the complexes within the cell nucleus. Here, the authors have analyzed the DNA binding properties of the dioxin receptor in wild-type mouse hepatoma (Hepa 1c1c7) cells and a class of nonresponsive mutant cells which fail to accumulate dioxin-receptor complexes within the nucleus in vivo. In vitro, both the wild-type and mutant [ 3 H]dioxin-receptor complexes exhibited low affinity for DNA-cellulose (5-8% and around 4% retention, respectively) in the absence of prior biochemical manipulations. However, following chromatography on heparin-Sepharose, the wild-type but not the mutant dioxin receptor was transformed to a species with an increased affinity for DNA (40-50% retention on DNA-cellulose). The gross molecular structure of the mutant, non DNA binding dioxin receptor did not appear to be altered as compared to that of the wild-type receptor. These results imply that the primary deficiency in the mutant dioxin receptor form may reside at the DNA binding level and that, in analogy to steroid hormone receptors, DNA binding of the receptor may be an essential step in the regulation of target gene transcription by dioxin

  4. (4Z-1-Dodecyl-4-(2-oxopropylidene-2,3,4,5-tetrahydro-1H-1,5-benzodiazepin-2-one

    Directory of Open Access Journals (Sweden)

    Jihad Sebhaoui

    2016-11-01

    Full Text Available In the title compound, C24H36N2O2, the orientation of the 2-oxopropylidene substituent is determined by the formation of an intramolecular N—H...O hydrogen bond. The benzodiazepine seven-membered ring adopts a slightly twisted boat conformation. The molecules pack in a bilayer fashion with the dodecyl chains intercalated to form the inner portion, and the benzodiazepine moieties on the outer surfaces.

  5. Prescriptions for schedule II opioids and benzodiazepines increase after the introduction of computer-generated prescriptions.

    Science.gov (United States)

    McGerald, Genevieve; Dvorkin, Ronald; Levy, David; Lovell-Rose, Stephanie; Sharma, Adhi

    2009-06-01

    Prescriptions for controlled substances decrease when regulatory barriers are put in place. The converse has not been studied. The objective was to determine whether a less complicated prescription writing process is associated with a change in the prescribing patterns of controlled substances in the emergency department (ED). The authors conducted a retrospective nonconcurrent cohort study of all patients seen in an adult ED between April 19, 2005, and April 18, 2007, who were discharged with a prescription. Prior to April 19, 2006, a specialized prescription form stored in a locked cabinet was obtained from the nursing staff to write a prescription for benzodiazepines or Schedule II opioids. After April 19, 2006, New York State mandated that all prescriptions, regardless of schedule classification, be generated on a specialized bar-coded prescription form. The main outcome of the study was to compare the proportion of Schedule III-V opioids to Schedule II opioids and benzodiazepines prescribed in the ED before and after the introduction of a less cumbersome prescription writing process. Of the 26,638 charts reviewed, 2.1% of the total number of prescriptions generated were for a Schedule II controlled opioid before the new system was implemented compared to 13.6% after (odds ratio [OR] = 7.3, 95% confidence interval [CI] = 6.4 to 8.4). The corresponding percentages for Schedule III-V opioids were 29.9% to 18.1% (OR = 0.52, 95% CI = 0.49 to 0.55) and for benzodiazepines 1.4% to 3.9% (OR = 2.8, 95% CI = 2.4 to 3.4). Patients were more likely to receive a prescription for a Schedule II opioid or a benzodiazepine after a more streamlined computer-generated prescription writing process was introduced in this ED. (c) 2009 by the Society for Academic Emergency Medicine.

  6. Change in healthcare utilization and costs following initiation of benzodiazepine therapy for long-term treatment of generalized anxiety disorder: a retrospective cohort study

    Directory of Open Access Journals (Sweden)

    Berger Ariel

    2012-10-01

    Full Text Available Abstract Background Selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors, and benzodiazepine anxiolytics are used in the US to treat generalized anxiety disorder (GAD. While benzodiazepines typically provide rapid symptomatic relief, long-term use is not recommended due to risks of dependency, sedation, falls, and accidents. Methods Using a US health insurance database, we identified all persons with GAD (ICD-9-CM diagnosis code 300.02 who began a long-term course of treatment (≥90 days with a benzodiazepine anxiolytic between 1/1/2003 and 12/31/2007, We compared healthcare utilization and costs over the six-month periods preceding and following the date of treatment initiation (“pretreatment” and “post-treatment”, respectively, and focused attention on accident-related encounters (e.g., for treatment of fractures and care received for other reasons possibly related benzodiazepine use (e.g., sedation, dizziness. Results A total of 866 patients met all study entry criteria; 25% of patients began treatment on an add-on basis (i.e., adjunctive to escitalopram, paroxetine, sertraline, or venlafaxine, while 75% of patients did not receive concomitant therapy. Mean total healthcare costs increased by $2334 between the pretreatment and post-treatment periods (from $4637 [SD=$9840] to $6971 [$17,002]; p Conclusions Healthcare costs increase in patients with GAD beginning long-term (≥90 days treatment with a benzodiazepine anxiolytic; a substantial proportion of this increase is attributable to care associated with accidents and other known sequelae of long-term benzodiazepine use.

  7. Temperament and character traits associated with the use of alcohol, cannabis, cocaine, benzodiazepines, and hallucinogens: evidence from a large Brazilian web survey

    Directory of Open Access Journals (Sweden)

    Ricardo Schneider Jr.

    2015-03-01

    Full Text Available Objectives: To evaluate how personality traits are associated with occasional use, abuse, and dependence of alcohol, cannabis, cocaine, benzodiazepines, and hallucinogens in a large availability sample of adults via online questionnaires. Methods: The sample consisted of 8,646 individuals (24.7% men and 75.3% women who completed an anonymous web survey. Involvement with drugs and temperament/character traits were assessed through the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST and the Temperament and Character Inventory - Revised (TCI-R, respectively. Interactions among variables were analyzed using MANOVA with Bonferroni adjustment. Results: Novelty seeking was the trait most associated with increased involvement with alcohol, cannabis, and cocaine. There was a significant association between harm avoidance and benzodiazepine use. Persistence was lower in cannabis-, benzodiazepine-, and cocaine-dependent subjects, as well as in hallucinogen abusers. Self-directedness was reduced in dependents of all drug classes. No strong relationships were found between other temperament or character dimensions and the severity of drug use. Conclusions: Novelty seeking was associated with increased involvement with all drugs studied in this sample, although to a lesser extent with benzodiazepines and hallucinogens. The temperament and character profile for benzodiazepine use was different from that of other drugs due to the relationship with higher harm avoidance and self-transcendence and lower self-directedness.

  8. Dependence and withdrawal reactions to benzodiazepines and selective serotonin reuptake inhibitors. How did the health authorities react?

    Science.gov (United States)

    Nielsen, Margrethe; Hansen, Ebba Holme; Gøtzsche, Peter C

    2013-01-01

    Our objective was to explore communications from drug agencies about benzodiazepine dependence and selective serotonin reuptake inhibitors (SSRIs) withdrawal reactions over time. Documentary study. We searched the web-sites of the European Medicines Agency and the drug agencies in USA, UK, and Denmark for documents mentioning benzodiazepines or SSRIs. We supplemented with other relevant literature that could contribute to our study. The searches were performed in 2009 in PubMed, Google, BMJ and JAMA. It took many years before the drug regulators acknowledged benzodiazepine dependence and SSRI withdrawal reactions and before the prescribers and the public were informed. Drug regulators relied mainly on the definitions of dependence and withdrawal reactions from the diagnostic psychiatric manuals, which contributed to the idea that SSRIs do not cause dependence, although it is difficult for many patients to stop treatment. In the perspective of a precautionary principle, drug agencies have failed to acknowledge that SSRIs can cause dependence and have minimised the problem with regard to its frequency and severity. In the perspective of a risk management principle, the drug agencies have reacted in concordance with the slowly growing knowledge of adverse drug reactions and have sharpened the information to the prescribers and the public over time. However, solely relying on spontaneous reporting of adverse effects leads to underestimation and delayed information about the problems. Given the experience with the benzodiazepines, we believe the regulatory bodies should have required studies from the manufacturers that could have elucidated the dependence potential of the SSRIs before marketing authorization was granted.

  9. Pyrrolobenzodiazepines (PBDs do not bind to DNA G-quadruplexes.

    Directory of Open Access Journals (Sweden)

    Khondaker M Rahman

    Full Text Available The pyrrolo[2,1-c][1,4] benzodiazepines (PBDs are a family of sequence-selective, minor-groove binding DNA-interactive agents that covalently attach to guanine residues. A recent publication in this journal (Raju et al, PloS One, 2012, 7, 4, e35920 reported that two PBD molecules were observed to bind with high affinity to the telomeric quadruplex of Tetrahymena glaucoma based on Electrospray Ionisation Mass Spectrometry (ESI-MS, Circular Dichroism, UV-Visible and Fluorescence spectroscopy data. This was a surprising result given the close 3-dimensional shape match between the structure of all PBD molecules and the minor groove of duplex DNA, and the completely different 3-dimensional structure of quadruplex DNA. Therefore, we evaluated the interaction of eight PBD molecules of diverse structure with a range of parallel, antiparallel and mixed DNA quadruplexes using DNA Thermal Denaturation, Circular Dichroism and Molecular Dynamics Simulations. Those PBD molecules without large C8-substitutents had an insignificant affinity for the eight quadruplex types, although those with large π-system-containing C8-substituents (as with the compounds evaluated by Raju and co-workers were found to interact to some extent. Our molecular dynamics simulations support the likelihood that molecules of this type, including those examined by Raju and co-workers, interact with quadruplex DNA through their C8-substituents rather than the PBD moiety itself. It is important for the literature to be clear on this matter, as the mechanism of action of these agents will be under close scrutiny in the near future due to the growing number of PBD-based agents entering the clinic as both single-agents and as components of antibody-drug conjugates (ADCs.

  10. Consequences of early postnatal benzodiazepines exposure in rats. I. Cognitive-like behavior

    Czech Academy of Sciences Publication Activity Database

    Mikulecká, Anna; Šubrt, Martin; Stuchlík, Aleš; Kubová, Hana

    2014-01-01

    Roč. 8, Mar 28 (2014), s. 101 ISSN 1662-5153 R&D Projects: GA ČR(CZ) GBP304/12/G069; GA ČR(CZ) GA305/09/0846 Institutional support: RVO:67985823 Keywords : benzodiazepines * clonazepam * cognitive functions * development * rats Subject RIV: FH - Neurology Impact factor: 3.270, year: 2014

  11. Multidisciplinary Prerounding Meeting as a Continuous Quality Improvement Tool: Leveraging to Reduce Continuous Benzodiazepine Use at an Academic Medical Center.

    Science.gov (United States)

    Flannery, Alexander H; Thompson Bastin, Melissa L; Montgomery-Yates, Ashley; Hook, Corrine; Cassity, Evan; Eaton, Phillip M; Morris, Peter E

    2018-01-01

    Evidence-based medicine often has many barriers to overcome prior to implementation in practice, hence the importance of continuous quality improvement. We report on a brief (≤10 minutes) multidisciplinary meeting prior to rounds to establish a dashboard for continuous quality improvement and studied the success of this meeting on a particular area of focus: continuous infusion benzodiazepine minimization. This was a prospective observational study of patients admitted to the medical intensive care unit (MICU) of a large academic medical center over a 4-month period. A morning multidisciplinary prerounding meeting was implemented to report on metrics required to establish a dashboard for MICU care for the previous 24 hours. Fellows and nurse practitioners on respective teams reported on key quality metrics and other important data related to patient census. Continuous benzodiazepines were tracked daily as the number of patients per team who had orders for a continuous benzodiazepine infusion. The aim of this report is to describe the development of the morning multidisciplinary prerounding meeting and its impact on continuous benzodiazepine use, along with associated clinical outcomes. The median number of patients prescribed a continuous benzodiazepine daily decreased over this time period and demonstrated a sustained reduction at 1 year. Furthermore, sedation scores improved, corresponding to a reduction in median duration of mechanical ventilation. The effectiveness of this intervention was mapped post hoc to conceptual models used in implementation science. A brief multidisciplinary meeting to review select data points prior to morning rounds establishes mechanisms for continuous quality improvement and may serve as a mediating factor for successful implementation when initiating and monitoring practice change in the ICU.

  12. Synthesis of spiro[indolo-1,5-benzodiazepines] from 3-acetyl ...

    Indian Academy of Sciences (India)

    Unknown

    also as potent virucides and non-nucleoside inhibi- tors of HIV-1 reverse transcriptase.2 Beside this,. 1,5-benzodiazepines ... printed circuits.8 Here we report the synthesis of spiro ... 3d. 5,6-Benzo 1727. 1701. 1672. 3218 3382. 4⋅22 (d, 2H, J = 17⋅91 Hz), 3⋅81 (d, 2H,. J = 17⋅8 .... R1 = R2 = CH3 show 88⋅88% inhibition.

  13. Impact of benzodiazepines on brain FDG-PET quantification after single-dose and chronic administration in rats

    International Nuclear Information System (INIS)

    Silva-Rodríguez, Jesús; García-Varela, Lara; López-Arias, Esteban; Domínguez-Prado, Inés; Cortés, Julia; Pardo-Montero, Juan; Fernández-Ferreiro, Anxo

    2016-01-01

    Introduction: Current guidelines for brain PET imaging advice against the injection of diazepam prior to brain FDG-PET examination in order to avoid possible interactions of benzodiazepines with the radiotracer uptake. Nevertheless, many patients undergoing PET studies are likely to be under chronic treatment with benzodiazepines, for example due to the use of different medications such as sleeping pills. Animal studies may provide an extensive and accurate estimation of the effect of benzodiazepines on brain metabolism in a well-defined and controlled framework. Aim: This study aims at evaluating the impact of benzodiazepines on brain FDG uptake after single-dose administration and chronic treatment in rats. Methods: Twelve Sprague–Dawley healthy rats were randomly divided into two groups, one treated with diazepam and the other used as control group. Both groups underwent PET/CT examinations after single-dose and chronic administration of diazepam (treated) or saline (controls) during twenty-eight days. Different atlas-based quantification methods were used to explore differences on the total uptake and uptake patterns of FDG between both groups. Results: Our analysis revealed a significant reduction of global FDG uptake after acute (−16.2%) and chronic (−23.2%) administration of diazepam. Moreover, a strong trend pointing to differences between acute and chronic administrations (p < 0.08) was also observed. Uptake levels returned to normal after interrupting the administration of diazepam. On the other hand, patterns of FDG uptake were not affected by the administration of diazepam. Conclusions: The administration of diazepam causes a progressive decrease of the FDG global uptake in the rat brain, but it does not change local patterns within the brain. Under these conditions, visual assessment and quantification methods based on regional differences such as asymmetry indexes or SPM statistical analysis would still be valid when administrating this

  14. The typing of Staphylococcus epidermidis by a lectin-binding assay

    DEFF Research Database (Denmark)

    Jarløv, J O; Hansen, J E; Rosdahl, V T

    1992-01-01

    A new typing method for Staphylococcus epidermidis was developed. Four biotinylated lectins--wheat germ agglutinin (WGA), soy bean agglutinin (SBA), lentil agglutinin (LCA) and Concanavalin A (ConA)--were added to immobilised whole cells of coagulase-negative staphylococci (CNS) in microtitration...... plates. The amount of bound lectin was measured by peroxidase-conjugated avidin followed by a peroxidase reaction. The method was compared to antibiotic-resistance analysis, phage typing, plasmid DNA profiles and slime production. A total of 113 isolates of CNS from 21 patients was investigated and 71...... strains of CNS, including 64 strains of S. epidermidis, were detected if all typing methods were taken into consideration. If only one typing method was used the highest discriminatory power among the S. epidermidis isolates was obtained with the lectin-binding assay which allowed 49 different strains...

  15. A single mutation in Taiwanese H6N1 influenza hemagglutinin switches binding to human-type receptors

    Energy Technology Data Exchange (ETDEWEB)

    de Vries, Robert P.; Tzarum, Netanel; Peng, Wenjie; Thompson, Andrew J.; Ambepitiya Wickramasinghe, Iresha N.; de la Pena, Alba T. Torrents; van Breemen, Marielle J.; Bouwman, Kim M.; Zhu, Xueyong; McBride, Ryan; Yu, Wenli; Sanders, Rogier W.; Verheije, Monique H.; Wilson, Ian A.; Paulson, James C.

    2017-07-10

    In June 2013, the first case of human infection with an avian H6N1 virus was reported in a Taiwanese woman. Although this was a single non-fatal case, the virus continues to circulate in Taiwanese poultry. As with any emerging avian virus that infects humans, there is concern that acquisition of human-type receptor specificity could enable transmission in the human population. Despite mutations in the receptor-binding pocket of the human H6N1 isolate, it has retained avian-type (NeuAcα2-3Gal) receptor specificity. However, we show here that a single nucleotide substitution, resulting in a change from Gly to Asp at position 225 (G225D), completely switches specificity to human-type (NeuAcα2-6Gal) receptors. Significantly, G225D H6 loses binding to chicken trachea epithelium and is now able to bind to human tracheal tissue. Structural analysis reveals that Asp225 directly interacts with the penultimate Gal of the human-type receptor, stabilizing human receptor binding.

  16. Bedside Heart Type Fatty Acid Binding Protein (H-FABP): Is an Early Predictive Marker of Cardiac Syncope

    International Nuclear Information System (INIS)

    Sonmez, B. M.; Yilmaz, F.; Durdu, T.; Hakbilir, O.; Ongar, M.; Ozturk, D.; Altinbilek, E.; Kavalci, C.; Turhan, T.

    2015-01-01

    Objective: To determine the value of bedside heart-type fatty acid binding protein in diagnosis of cardiac syncope in patients presenting with syncope or presyncope. Methods: The prospective study was conducted at Ankara Numune Training and Research Hospital, Ankara, Turkey, between September 1, 2010, and January 1, 2011, and comprised patients aged over 18 years who presented with syncope or presyncope. Patients presenting to emergency department within 4 hours of syncope or presyncope underwent a bedside heart-type fatty acid binding protein test measurement. SPSS 16 was used for statistical analysis, Results: Of the 100 patients evaluated, 22(22 percent) were diagnosed with cardiac syncope. Of them, 13(59.1 percent) patients had a positive and 9(40.9 percent) had a negative heart-type fatty acid binding protein result. Consequently, the test result was 12.64 times more positive in patients with cardiac syncope compared to those without. Conclusions: Bedside heart-type fatty acid binding protein, particularly at early phase of myocardial injury, reduces diagnostic and therapeutic uncertainity of cardiac origin in syncope patients. (author)

  17. Regulation of GABA and benzodiazepine receptors following neurotoxin-induced striatal and medial forebrain bundle lesions

    International Nuclear Information System (INIS)

    Pan, H.S.I.

    1985-01-01

    GABA, a major inhibitory transmitter, is used by many projection neurons of the striatum. To investigate the role of GABA in striatal function, the GABA receptor complex was studied after lesions of the striatum or the nigrostriatal neurons. Quantitative receptor autoradiography using thaw-mounted tissue slices was developed for the study of GABA and benzodiazepine (BDZ) receptors. With the technique established, binding to GABA and BDZ receptors after unilateral striatal kainate lesions was examined. Subsequently, changes in GABA and BDZ receptors were studied following the destruction of dopaminergic nigrostriatal cells by unilateral 6-hydroxydopamine lesion of the medial forebrain bundle. In summary, quantitative receptor autoradiography allowed the detection of GABA and BDZ receptor changes in multiple small areas in each lesioned brain. This technique made it feasible to carry out kinetic saturation, and competition studies using less than 1 mg of tissue. The data suggest that dopamine is functionally inhibitory on striatopallidal neurons but is functionally excitatory on striatoentopeduncular and striatonigral cells which in turn inhibit the thalamus. This quantitative autoradiographic technique can be generalized to study other transmitter receptors and can be combined with 2-deoxyglucose uptake studies

  18. Synthesis and in vivo evaluation of [11C]zolpidem, an imidazopyridine with agonist properties at central benzodiazepine receptors

    International Nuclear Information System (INIS)

    Dumont, Filip; Waterhouse, Rikki N.; Montoya, Julie A.; Mattner, Filomena; Katsifis, Andrew; Kegeles, Lawrence S.; Laruelle, Marc

    2003-01-01

    The synthesis and evaluation of [ 11 C]zolpidem, an imidazopyridine with agonist properties at central benzodiazepine receptors, is reported herein. The reaction of desmethylzolpidem with [ 11 C] methyl iodide afforded the title compound [ 11 C]zolpidem in a yield of 19.19 ± 3.23% in 41 ± 2 min in specific activities of 0.995-1.19 Ci/μmol (1.115 ± 0.105 Ci/μmol) (n = 3; decay corrected, EOB). The amount of radioactivity in the brain after tail vein injection in male Wistar rats was low, and the regional distribution was homogeneous and not consistent with the known distribution of the central benzodiazepine receptors. The frontal cortex/cerebellum ratio was not significantly greater than one (1.007 ± 0.266 at 5 min) and did not increase from 5 to 40 min post-injection. A PET brain imaging study in one baboon confirmed the results obtained in rats. Therefore, it can be concluded that [ 11 C]zolpidem is not a suitable tracer for in vivo visualization of central benzodiazepine receptors

  19. Synthesis and in vivo evaluation of [11C]zolpidem, an imidazopyridine with agonist properties at central benzodiazepine receptors.

    Science.gov (United States)

    Dumont, Filip; Waterhouse, Rikki N; Montoya, Julie A; Mattner, Filomena; Katsifis, Andrew; Kegeles, Lawrence S; Laruelle, Marc

    2003-05-01

    The synthesis and evaluation of [(11)C]zolpidem, an imidazopyridine with agonist properties at central benzodiazepine receptors, is reported herein. The reaction of desmethylzolpidem with [(11)C] methyl iodide afforded the title compound [(11)C]zolpidem in a yield of 19.19 +/- 3.23% in 41 +/- 2 min in specific activities of 0.995-1.19 Ci/micromol (1.115 +/- 0.105 Ci/micromol) (n = 3; decay corrected, EOB). The amount of radioactivity in the brain after tail vein injection in male Wistar rats was low, and the regional distribution was homogeneous and not consistent with the known distribution of the central benzodiazepine receptors. The frontal cortex/cerebellum ratio was not significantly greater than one (1.007 +/- 0.266 at 5 min) and did not increase from 5 to 40 min post-injection. A PET brain imaging study in one baboon confirmed the results obtained in rats. Therefore, it can be concluded that [(11)C]zolpidem is not a suitable tracer for in vivo visualization of central benzodiazepine receptors.

  20. Binding of von Willebrand factor to collagen type III: role of specific amino acids in the collagen binding domain of vWF and effects of neighboring domains

    NARCIS (Netherlands)

    van der Plas, R. M.; Gomes, L.; Marquart, J. A.; Vink, T.; Meijers, J. C.; de Groot, P. G.; Sixma, J. J.; Huizinga, E. G.

    2000-01-01

    Binding of von Willebrand Factor (vWF) to sites of vascular injury is the first step of hemostasis. Collagen types I and III are important binding sites for vWF. We have previously determined the three-dimensional structure of the collagen binding A3 domain of vWF (Huizinga et al., Structure 1997;

  1. Studies of the electronic structure and biological activity of chosen 1,4-benzodiazepines by {sup 35}Cl NQR spectroscopy and DFT calculations

    Energy Technology Data Exchange (ETDEWEB)

    Bronisz, K. [Department of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznan (Poland); Ostafin, M. [Department of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznan (Poland)], E-mail: ostifnqr@amu.edu.pl; Poleshchuk, O. Kh. [Department of Chemistry, Tomsk Pedagogical University, Komsomolskii 75, 634041 Tomsk (Russian Federation); Mielcarek, J. [Faculty of Pharmacy, University of Medical Sciences, Grunwaldzka 6, 60-780 Poznan (Poland); Nogaj, B. [Department of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznan (Poland)

    2006-11-08

    Selected derivatives of 1,4-benzodiazepine: lorazepam, lormetazepam, oxazepam and temazepam, used as active substances in anxiolytic drugs, have been studied by {sup 35}Cl NQR method in order to find the correlation between electronic structure and biological activity. The {sup 35}Cl NQR resonance frequencies ({nu} {sub Q}) measured at 77 K have been correlated with the following parameters characterising their biological activity: biological half-life period (t {sub 0.5}), affinity to benzodiazepine receptor (IC{sub 50}) and mean dose equivalent. The results of experimental study of some benzodiazepine derivatives by nuclear quadrupole resonance of {sup 35}Cl nuclei are compared with theoretical results based on DFT calculations which were carried out by means of Gaussian'98 W software.

  2. One-step purification of rat heart-type fatty acid-binding protein expressed in Escherichia coli

    NARCIS (Netherlands)

    Schaap, F. G.; Specht, B.; van der Vusse, G. J.; Börchers, T.; Glatz, J. F.

    1996-01-01

    Heart-type fatty acid-binding protein (H-FABP) is a member of a family of 14-15 kDa lipid binding proteins which are believed to enhance intracellular transport of lipids by facilitating their cytoplasmic diffusion. To obtain sufficient amounts of protein for in vitro studies, we expressed rat

  3. Benzodiazepines still play a role in modern psychiatric therapy

    DEFF Research Database (Denmark)

    Jørgensen, Martin Balslev; Videbech, Poul; Osler, Merete

    2017-01-01

    Benzodiazepines (BZ) are widely used for anxiety across psychiatric diagnoses, but for the last decades regulation has been increasingly tight due to problems with tolerance, addiction, withdrawal symptoms and cognitive side effects. Some guidelines claim that BZ only work for a few weeks......, and that BZ cause traffic accidents, increased mortality and dementia. In Denmark, the use of BZ has been substantially reduced. In this article it is argued, that not all patients habituate, that most of the epidemiological findings are hampered by confounding, and that there still is a role for long...

  4. Contribution of prolonged-release melatonin and anti-benzodiazepine campaigns to the reduction of benzodiazepine and Z-drugs consumption in nine European countries.

    Science.gov (United States)

    Clay, Emilie; Falissard, Bruno; Moore, Nicholas; Toumi, Mondher

    2013-04-01

    Benzodiazepines (BZD) and benzodiazepine receptor agonists (zolpidem, zaleplon, zopiclone, altogether Z-drugs) are most commonly prescribed for the treatment of insomnia. However, long-term use of BZD/Z-drugs is associated with major adverse events including, but not limited to, falls and fractures, domestic and traffic accidents, confusion, cognitive impairment, Alzheimer's disease and cancer. The prolonged use of these drugs is thought to be related to severe withdrawal symptoms and potential dependency. The chronic and extensive use of BZD/Z drugs has become a public health issue and has led to multiple campaigns to reduce both prescription and consumption of BZD/Z-drugs. Prolonged-release (PR) melatonin is the first of a new class of melatonin receptor agonist drugs that has demonstrated clinically relevant efficacy on improving quality of sleep and morning alertness, with a good safety profile. This study aimed to analyze and evaluate the impact of anti-BZD/Z-drugs campaigns and the availability of alternative pharmacotherapy (PR-melatonin) on the consumption of BZD and Z-drugs in several European countries. Annual sales data from nine European countries were extracted from the IMS sales database and analyzed to determine whether trends in use of these treatment options were attributed to campaigns and/or availability and affordability of safer alternatives on the market. Campaigns aiming to reduce the use of BZD/Z-drugs failed when they were not associated with the availability and market uptake of PR-melatonin. The reimbursement of PR-melatonin supports better penetration rates and a higher reduction in sales for BZD/Z-drugs.

  5. Evaluation of anti-hyperalgesic and analgesic effects of two benzodiazepines in human experimental pain: a randomized placebo-controlled study.

    Directory of Open Access Journals (Sweden)

    Pascal H Vuilleumier

    Full Text Available Compounds that act on GABA-receptors produce anti-hyperalgesia in animal models, but little is known on their effects in humans. The aim of this study was to explore the potential usefulness of GABA-agonism for the control of pain in humans. Two agonists at the benzodiazepine-binding site of GABAA-receptors (clobazam and clonazepam were studied using multiple experimental pain tests. Positive results would support further investigation of GABA agonism for the control of clinical pain.In a randomized double-blind crossover design, 16 healthy male volunteers received clobazam 20 mg, clonazepam 1 mg and tolterodine 1 mg (active placebo. The area of static hyperalgesia after intradermal capsaicin injection was the primary endpoint. Secondary endpoints were: area of dynamic hyperalgesia, response to von Frey hair stimulation, pressure pain thresholds, conditioned pain modulation, cutaneous and intramuscular electrical pain thresholds (1, 5 and 20 repeated stimulation, and pain during cuff algometry.For the primary endpoint, an increase in the area of static hyperalgesia was observed after administration of placebo (p<0.001, but not after clobazam and clonazepam. Results suggestive for an anti-hyperalgesic effect of the benzodiazepines were obtained with all three intramuscular pain models and with cuff algometry. No effect could be detected with the other pain models employed.Collectively, the results are suggestive for a possible anti-hyperalgesic effect of drugs acting at the GABAA-receptors in humans, particularly in models of secondary hyperalgesia and deep pain. The findings are not conclusive, but support further clinical research on pain modulation by GABAergic drugs. Because of the partial results, future research should focus on compounds acting selectively on subunits of the GABA complex, which may allow the achievement of higher receptor occupancy than unselective drugs. Our data also provide information on the most suitable experimental

  6. PET Centre and Centre for Functionally Integrative Neuroscience, Aarhus University

    DEFF Research Database (Denmark)

    Cumming, Paul; Pedersen, Mads Damgaard; Minuzzi, Luciano

    2006-01-01

    The cerebral distribution of peripheral-type benzodiazepine binding sites (PBBS) in human brain has been investigated by positron emission tomography (PET) with the specific radioligand [11C]PK11195 in diverse neuropathological conditions. However, little is known about the pattern of PK11195 bin...

  7. The Use of Benzodiazepine Receptor Agonists and Risk of Respiratory Failure in Patients with Chronic Obstructive Pulmonary Disease: A Nationwide Population-Based Case-Control Study

    Science.gov (United States)

    Chen, Su-Jung; Yeh, Chiu-Mei; Chao, Tze-Fan; Liu, Chia-Jen; Wang, Kang-Ling; Chen, Tzeng-Ji; Chou, Pesus; Wang, Fu-Der

    2015-01-01

    Study Objectives: Insomnia is prevalent in patients with chronic obstructive pulmonary disease (COPD), and benzodiazepine receptor agonists (BZRAs) are the most commonly used drugs despite their adverse effects on respiratory function. The aim of this study was to investigate whether the use of BZRAs was associated with an increased risk of respiratory failure (RF) in COPD patients. Design: Matched case-control study. Setting: National Health Insurance Research Database (NHIRD) in Taiwan. Participants: The case group consisted of 2,434 COPD patients with RF, and the control group consisted of 2,434 COPD patients without RF, matched for age, sex, and date of enrollment. Measurements and Results: Exposure to BZRAs during the 180-day period preceding the index date was analyzed and compared in the case and control groups. Conditional logistic regression was performed, and the use of BZRAs was associated with an increased risk of RF (adjusted odds ratio [aOR] 1.56, 95% confidence interval [CI] 1.14–2.13). In subgroup analysis, we found that the benzodiazepine (BZD) users had a higher risk of RF (aOR 1.58, 95% CI 1.14–2.20), whereas the risk in non-benzodiazepine (non-BZD) users was insignificant (aOR 0.85, 95% CI 0.51–1.44). A greater than 2-fold increase in risk was found in those who received two or more kinds of BZRAs and those using a combination of BZD and non-BZD medications. Conclusions: The use of benzodiazepine receptor agonists was a significant risk factor for respiratory failure in patients with chronic obstructive pulmonary disease (COPD). Compared to benzodiazepine, the prescription of non-benzodiazepine may be safer for the management of insomnia in COPD patients. Citation: Chen SJ, Yeh CM, Chao TF, Liu CJ, Wang KL, Chen TJ, Chou P, Wang FD. The use of benzodiazepine receptor agonists and risk of respiratory failure in patients with chronic obstructive pulmonary disease: a nationwide population-based case-control study. SLEEP 2015;38(7):1045–1050

  8. The Use of Benzodiazepine Receptor Agonists and Risk of Respiratory Failure in Patients with Chronic Obstructive Pulmonary Disease: A Nationwide Population-Based Case-Control Study.

    Science.gov (United States)

    Chen, Su-Jung; Yeh, Chiu-Mei; Chao, Tze-Fan; Liu, Chia-Jen; Wang, Kang-Ling; Chen, Tzeng-Ji; Chou, Pesus; Wang, Fu-Der

    2015-07-01

    Insomnia is prevalent in patients with chronic obstructive pulmonary disease (COPD), and benzodiazepine receptor agonists (BZRAs) are the most commonly used drugs despite their adverse effects on respiratory function. The aim of this study was to investigate whether the use of BZRAs was associated with an increased risk of respiratory failure (RF) in COPD patients. Matched case-control study. National Health Insurance Research Database (NHIRD) in Taiwan. The case group consisted of 2,434 COPD patients with RF, and the control group consisted of 2,434 COPD patients without RF, matched for age, sex, and date of enrollment. Exposure to BZRAs during the 180-day period preceding the index date was analyzed and compared in the case and control groups. Conditional logistic regression was performed, and the use of BZRAs was associated with an increased risk of RF (adjusted odds ratio [aOR] 1.56, 95% confidence interval [CI] 1.14-2.13). In subgroup analysis, we found that the benzodiazepine (BZD) users had a higher risk of RF (aOR 1.58, 95% CI 1.14-2.20), whereas the risk in non-benzodiazepine (non-BZD) users was insignificant (aOR 0.85, 95% CI 0.51-1.44). A greater than 2-fold increase in risk was found in those who received two or more kinds of BZRAs and those using a combination of BZD and non-BZD medications. The use of benzodiazepine receptor agonists was a significant risk factor for respiratory failure in patients with chronic obstructive pulmonary disease (COPD). Compared to benzodiazepine, the prescription of non-benzodiazepine may be safer for the management of insomnia in COPD patients. © 2015 Associated Professional Sleep Societies, LLC.

  9. Synthesis and in vivo evaluation of [{sup 11}C]zolpidem, an imidazopyridine with agonist properties at central benzodiazepine receptors

    Energy Technology Data Exchange (ETDEWEB)

    Dumont, Filip; Waterhouse, Rikki N. E-mail: rnw7@columbia.edu; Montoya, Julie A.; Mattner, Filomena; Katsifis, Andrew; Kegeles, Lawrence S.; Laruelle, Marc

    2003-05-01

    The synthesis and evaluation of [{sup 11}C]zolpidem, an imidazopyridine with agonist properties at central benzodiazepine receptors, is reported herein. The reaction of desmethylzolpidem with [{sup 11}C] methyl iodide afforded the title compound [{sup 11}C]zolpidem in a yield of 19.19 {+-} 3.23% in 41 {+-} 2 min in specific activities of 0.995-1.19 Ci/{mu}mol (1.115 {+-} 0.105 Ci/{mu}mol) (n = 3; decay corrected, EOB). The amount of radioactivity in the brain after tail vein injection in male Wistar rats was low, and the regional distribution was homogeneous and not consistent with the known distribution of the central benzodiazepine receptors. The frontal cortex/cerebellum ratio was not significantly greater than one (1.007 {+-} 0.266 at 5 min) and did not increase from 5 to 40 min post-injection. A PET brain imaging study in one baboon confirmed the results obtained in rats. Therefore, it can be concluded that [{sup 11}C]zolpidem is not a suitable tracer for in vivo visualization of central benzodiazepine receptors.

  10. Characterization of the SUMO-binding activity of the myeloproliferative and mental retardation (MYM-type zinc fingers in ZNF261 and ZNF198.

    Directory of Open Access Journals (Sweden)

    Catherine M Guzzo

    Full Text Available SUMO-binding proteins interact with SUMO modified proteins to mediate a wide range of functional consequences. Here, we report the identification of a new SUMO-binding protein, ZNF261. Four human proteins including ZNF261, ZNF198, ZNF262, and ZNF258 contain a stretch of tandem zinc fingers called myeloproliferative and mental retardation (MYM-type zinc fingers. We demonstrated that MYM-type zinc fingers from ZNF261 and ZNF198 are necessary and sufficient for SUMO-binding and that individual MYM-type zinc fingers function as SUMO-interacting motifs (SIMs. Our binding studies revealed that the MYM-type zinc fingers from ZNF261 and ZNF198 interact with the same surface on SUMO-2 recognized by the archetypal consensus SIM. We also present evidence that MYM-type zinc fingers in ZNF261 contain zinc, but that zinc is not required for SUMO-binding. Immunofluorescence microscopy studies using truncated fragments of ZNF198 revealed that MYM-type zinc fingers of ZNF198 are necessary for localization to PML-nuclear bodies (PML-NBs. In summary, our studies have identified and characterized the SUMO-binding activity of the MYM-type zinc fingers in ZNF261 and ZNF198.

  11. Radiosynthesis and in vivo evaluation of N-[11C]methylated imidazopyridineacetamides as PET tracers for peripheral benzodiazepine receptors

    International Nuclear Information System (INIS)

    Sekimata, Katsuhiko; Hatano, Kentaro; Ogawa, Mikako; Abe, Junichiro; Magata, Yasuhiro; Biggio, Giovanni; Serra, Mariangela; Laquintana, Valentino; Denora, Nunzio; Latrofa, Andrea; Trapani, Giuseppe; Liso, Gaetano; Ito, Kengo

    2008-01-01

    Imidazopyridineacetoamide 5-8, a series of novel and potentially selective peripheral benzodiazepine receptor (PBR) ligands with affinities comparable to those of known PBR ligands, was investigated. Radiosyntheses of [ 11 C]5, 6, 7 or 8 was accomplished by N-methylation of the corresponding desmethyl precursors with [ 11 C]methyl iodide in the presence of NaH in dimethylformamide (DMF), resulting in 25% to 77% radiochemical yield and specific activitiy of 20 to 150 MBq/nmol. Each of the labeled compounds was injected in ddY mice, and the radioactivity and weight of dissected peripheral organs and brain regions were measured. Organ distribution of [ 11 C]7 was consistent with the known PBR distribution. Moreover, [ 11 C]7 showed the best combination of brain uptake and PBR binding, leading to its high retention in the olfactory bulb and cerebellum, areas where PBR density is high in mouse brain. Coinjection of PK11195 or unlabeled 7 significantly reduced the brain uptake of [ 11 C]7. These results suggest that [ 11 C]7 could be a useful radioligand for positron emission tomography imaging of PBRs

  12. Crystal structure of the botulinum neurotoxin type G binding domain: insight into cell surface binding.

    Science.gov (United States)

    Stenmark, Pål; Dong, Min; Dupuy, Jérôme; Chapman, Edwin R; Stevens, Raymond C

    2010-04-16

    Botulinum neurotoxins (BoNTs) typically bind the neuronal cell surface via dual interactions with both protein receptors and gangliosides. We present here the 1.9-A X-ray structure of the BoNT serotype G (BoNT/G) receptor binding domain (residues 868-1297) and a detailed view of protein receptor and ganglioside binding regions. The ganglioside binding motif (SxWY) has a conserved structure compared to the corresponding regions in BoNT serotype A and BoNT serotype B (BoNT/B), but several features of interactions with the hydrophilic face of the ganglioside are absent at the opposite side of the motif in the BoNT/G ganglioside binding cleft. This may significantly reduce the affinity between BoNT/G and gangliosides. BoNT/G and BoNT/B share the protein receptor synaptotagmin (Syt) I/II. The Syt binding site has a conserved hydrophobic plateau located centrally in the proposed protein receptor binding interface (Tyr1189, Phe1202, Ala1204, Pro1205, and Phe1212). Interestingly, only 5 of 14 residues that are important for binding between Syt-II and BoNT/B are conserved in BoNT/G, suggesting that the means by which BoNT/G and BoNT/B bind Syt diverges more than previously appreciated. Indeed, substitution of Syt-II Phe47 and Phe55 with alanine residues had little effect on the binding of BoNT/G, but strongly reduced the binding of BoNT/B. Furthermore, an extended solvent-exposed hydrophobic loop, located between the Syt binding site and the ganglioside binding cleft, may serve as a third membrane association and binding element to contribute to high-affinity binding to the neuronal membrane. While BoNT/G and BoNT/B are homologous to each other and both utilize Syt-I/Syt-II as their protein receptor, the precise means by which these two toxin serotypes bind to Syt appears surprisingly divergent. Copyright (c) 2010. Published by Elsevier Ltd.

  13. Bioassay-guided isolation of apigenin with GABA-benzodiazepine activity from Tanacetum parthenium

    DEFF Research Database (Denmark)

    Jäger, Anna Katharina; Krydsfeldt, Katrine; Rasmussen, Hasse Bonde

    2009-01-01

    Extracts of Tanacetum parthenium are used in the prophylactic treatment of migraine and have also been used in Danish folk medicine for the treatment of epilepsy. An ethanol extract of T. parthenium showed high affinity for the GABA(A)-benzodiazepine site. An ethanol extract of T. parthenium was ...

  14. Acute myocardial infarction with multiple coronary thromboses in a young addict of amphetamines and benzodiazepines

    Directory of Open Access Journals (Sweden)

    Mohammed A. Al Shehri

    2016-07-01

    Full Text Available A 35-year-old man of average build and a smoker, with a background of a psychiatric disorder, was brought by his neighbor to the emergency department after an hour of severe chest pain. Upon arrival at the hospital he had cardiac arrest, was resuscitated, and moved to the catheterization laboratory with inferior, posterior, and lateral myocardial infarction. Coronary angiography showed an unusual thrombosis in multiple coronary branches. Toxicology report showed high levels of amphetamines and benzodiazepines in the patient’s original blood sample. The patient was kept under ventilation for 18 days, with difficult recovery due to severe withdrawal manifestations, ventilation acquired pneumonia, and rhabdomyolysis inducing acute renal failure. The patient regained near normal left ventricular function after baseline severe regional and global dysfunction. We postulate a relationship between the use of amphetamines, potentiated by benzodiazepines, and occurrence of acute thrombosis of multiple major coronary arteries.

  15. Identification of Molecular Substrate for the Attenuation of Anxiety: A Step Toward the Development of Better Anti-Anxiety Drugs

    Directory of Open Access Journals (Sweden)

    Uwe Rudolph

    2001-01-01

    Full Text Available Anxiety disorders affect some 19 million people in the U.S. alone, costing $46.6 billion, or one third of the nation’s total mental health bill in 1990. Benzodiazepine tranquilizers like the prototypic diazepam are among the most widely used anti-anxiety agents. In addition to their anxiolytic action, they also induce sedation and may impair motor coordination, both of which are undesired side effects when they are used as anxiolytics. Not surprisingly, road traffic accidents may be increased for patients on classical benzodiazepines. In addition, these drugs carry the risk of dependence liability. Benzodiazepines augment the action of the inhibitory neurotransmitter g-aminobutyric acid (GABA at contact points between two nerve cells called synapses, points at which information is transmitted from one nerve cell to the next. Synaptically released GABA binds to postsynaptic GABAA receptors, thus causing an influx of negatively charged chloride ions into the postsynaptic neuron. This leads to a hyperpolarization and thus functional inhibition of the postsynaptic cell. Benzodiazepines bind to a site on the GABAA receptor which is different from the GABA binding site, thus increasing the chloride current. Benzodiazepines like diazepam bind to GABAA receptors containing the α subunits α1, α2, α3, or α5, most likely in abgabg combinations.

  16. QuEChERS extraction of benzodiazepines in biological matrices

    Directory of Open Access Journals (Sweden)

    Jessica L. Westland

    2013-12-01

    Full Text Available Two common analytical chemical problems often encountered when using chromatographic techniques in drug analysis are matrix interferences and ion suppression. Common sample preparation often involves the dilution of the sample prior to injection onto an instrument, especially for liquid chromatography–mass spectrometry (LC–MS analyses. This practice frequently does not minimize or eliminate conditions that may cause ion-suppression and therefore, suffer more from reduced method robustness. In order to achieve higher quality results and minimize possible interferences, various sample preparation techniques may be considered. Through the use of QuEChERS (“catchers”, a novel sample preparation technique used for high aqueous content samples, benzodiazepines can be extracted from biological fluids, such as blood and urine. This approach has shown increased recoveries of target compounds when using quantification by both external and internal standard. This increase in the recoveries has been attributed to a matrix enhancement and was determined through the use of the method of standard addition. While improving the overall analytical method for gas chromatography–mass spectrometry (GC–MS analysis, it is not clear if this approach represents an overall benefit for laboratories that have both GC–MS and high performance liquid chromatography tandem mass spectrometry (HPLC–MS/MS capability. Demonstrating evidence of variable ionization (enhancement, ion source inertness, etc., the method of quantification should be focused on in future studies. Keywords: Forensic science, QuEChERS, Drug analysis, Benzodiazepines, Gas Chromatography–Mass Spectrometry, Biological samples

  17. Assessment of the Availability, Cost, and Motivations for Use over Time of the New Psychoactive Substances-Benzodiazepines Diclazepam, Flubromazepam, and Pyrazolam-in the UK.

    Science.gov (United States)

    Abouchedid, Rachelle; Gilks, Thea; Dargan, Paul I; Archer, John R H; Wood, David M

    2018-06-01

    There has been increasing interest in the availability of non-prescription benzodiazepines and their sale as new psychoactive substances. We wanted to determine UK availability from Internet suppliers and motivations for use of three benzodiazepines (diclazepam, flubromazepam, and pyrazolam). In November 2014 and March 2016, using the European Monitoring Centre for Drugs and Drug Addiction Snapshot Methodology, Internet search engines ( google.co.uk , uk. yahoo.com and ask.com.uk ) were searched using the terms 'buy diclazepam', 'buy flubromazepam' and 'buy pyrazolam'. Threads from drug-user forums ( bluelight.org , drugs-forum.com , erowid.org , legalhighsforum.com ) were analysed using a general inductive approach. Data were converted into price per gram/pellet to allow cost comparisons and to determine motivations for use. There was an increase in websites selling these benzodiazepines between 2014 and 2016: diclazepam (49 in 2014 to 55 in 2016), pyrazolam (33 to 35), and flubromazepam (39 to 45). Thirty-eight (63.3%) sites were based in the UK/Europe. Drugs were sold as pellets (49 websites, 81.7%), powder (19, 31.7%), and blotters (1, 1.7%). Pill forms were not available, and one (1.7%) website sold diclazepam/flubromazepam in liquid form. The cost reduced with increasing purchase quantities. Main motivations for use included anxiolysis, management of benzodiazepine withdrawal, sedation/sleep aid, and management of stimulant withdrawal. These three benzodiazepines are widely available online, most commonly as pellets, and are (mis)used for a number of reasons. This study could be used to support triangulation of data from other sources to inform harm minimisation strategies.

  18. Quantification of (R)-[11C]PK11195 binding in rheumatoid arthritis

    International Nuclear Information System (INIS)

    Kropholler, M.A.; Boellaard, R.; Kloet, R.W.; Lammertsma, A.A.; Elzinga, E.H.; Voskuyl, A.E.; Laken, C.J. van der; Dijkmans, B.A.C.; Maruyama, K.

    2009-01-01

    Rheumatoid arthritis (RA) involves migration of macrophages into inflamed areas. (R)-[ 11 C]PK11195 binds to peripheral benzodiazepine receptors, expressed on macrophages, and may be used to quantify inflammation using positron emission tomography (PET). This study evaluated methods for the quantification of (R)-[ 11 C]PK11195 binding in the knee joints of RA patients. Data from six patients with RA were analysed. Dynamic PET scans were acquired in 3-D mode following (R)-[ 11 C]PK11195 injection. During scanning arterial radioactivity concentrations were measured to determine the plasma (R)-[ 11 C]PK11195 concentrations. Data were analysed using irreversible and reversible one-tissue and two-tissue compartment models and input functions with various types of metabolite correction. Model preferences according to the Akaike information criterion (AIC) and correlations between measures were evaluated. Correlations between distribution volume (V d ) and standardized uptake values (SUV) were evaluated. AIC indicated optimal performance for a one-tissue reversible compartment model including blood volume. High correlations were observed between V d obtained using different input functions (R 2 =0.80-1.00) and between V d obtained with one- and two-tissue reversible compartment models (R 2 =0.75-0.94). A high correlation was observed between optimal V d and SUV after injection (R 2 =0.73). (R)-[ 11 C]PK11195 kinetics in the knee were best described by a reversible single-tissue compartment model including blood volume. Applying metabolite corrections did not increase sensitivity. Due to the high correlation with V d , SUV is a practical alternative for clinical use. (orig.)

  19. Structural Analysis of Botulinum Neurotoxin Type G Receptor Binding

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, John; Karalewitz, Andrew; Benefield, Desire A.; Mushrush, Darren J.; Pruitt, Rory N.; Spiller, Benjamin W.; Barbieri, Joseph T.; Lacy, D. Borden (Vanderbilt); (MCW)

    2010-10-19

    Botulinum neurotoxin (BoNT) binds peripheral neurons at the neuromuscular junction through a dual-receptor mechanism that includes interactions with ganglioside and protein receptors. The receptor identities vary depending on BoNT serotype (A-G). BoNT/B and BoNT/G bind the luminal domains of synaptotagmin I and II, homologous synaptic vesicle proteins. We observe conditions under which BoNT/B binds both Syt isoforms, but BoNT/G binds only SytI. Both serotypes bind ganglioside G{sub T1b}. The BoNT/G receptor-binding domain crystal structure provides a context for examining these binding interactions and a platform for understanding the physiological relevance of different Syt receptor isoforms in vivo.

  20. Assaying of drugs in body fluids

    International Nuclear Information System (INIS)

    Braestrup, C.; Squires, R.F.

    1981-01-01

    The invention provides, in general terms, a process for determining the concentration of a psychotropically active benzodiazepine drug in blood or other body fluid or urine, including bringing a sample of the fluid or urine into contact with brain tissue and with tritium labelled molecules of a benzodiazepine which can bind reversibly to receptors of the brain tissue to induce binding of molecules of the unlabelled drug and of the tritium labelled benzodiazepine to the receptors, and determining the radioactivity of the brain tissue, preferably by scintillation counting. (author)

  1. Latent trait standardization of the benzodiazepine dependence self-report questionnaire using the Rasch scaling model.

    NARCIS (Netherlands)

    Kan, C.C.; Ven, A.H.G.S. van der; Breteler, M.H.M.; Zitman, F.G.

    2001-01-01

    The aim of the present study was to obtain standardized scores that correspond with the raw scores on the four Rasch scales of the Benzodiazepine Dependence-Self Report Questionnaire (Bendep-SRQ). The eligible normative group for standardization of the Bendep-SRQ scales consisted of 217 general

  2. Latent Trait Standardization of the Benzodiazepine Dependence Self-Report Questionnaire using the Rasch Scaling Model

    NARCIS (Netherlands)

    Kan, C.C.; Ven, A.H.G.S. van der; Breteler, M.H.M.; Zitman, F.G.

    2001-01-01

    The aim of the present study was to obtain standardized scores that correspond with the raw scores on the four Rasch scales of the Benzodiazepine Dependence-Self Report Questionnaire (Bendep-SRQ). The eligible normative group for standardization of the Bendep-SRQ scales consisted of 217 general

  3. Modulation of acetylcholine release from rat striatal slices by the GABA/benzodiazepine receptor complex

    Energy Technology Data Exchange (ETDEWEB)

    Supavilai, P.; Karobath, M.

    1985-02-04

    GABA, THIP and muscimol enhance spontaneous and inhibit electrically induced release of tritium labelled compounds from rat striatal slices which have been pre-labelled with /sup 3/H-choline. Baclofen is inactive in this model. Muscimol can inhibit electrically induced release of tritiated material by approximately 75% with half maximal effects at 2 ..mu..M. The response to muscimol can be blocked by the GABA antagonists bicuculline methobromide, picrotoxin, anisatin, R 5135 and CPTBO (cyclopentylbicyclophosphate). Drugs which act on the benzodiazepine receptor (BR) require the presence of muscimol to be effective and they modulate the effects of muscimol in a bidirectional manner. Thus BR agonists enhance and inverse BR agonists attenuate the inhibitory effects of muscimol on electrically induced release. Ro15-1788, a BR antagonist, does not modulate the inhibitory effects of muscimol but antagonizes the actions of clonazepam, a BR agonist, and of DMCM, an inverse BR agonist. These results demonstrate that a GABA/benzodiazepine receptor complex can modulate acetylcholine release from rat striatal slices in vitro. 24 references, 3 figures, 5 table.

  4. Maternal Characteristics of Women Exposed to Hypnotic Benzodiazepine Receptor Agonist during Pregnancy

    OpenAIRE

    Askaa, Bjarke; Jimenez-Solem, Espen; Enghusen Poulsen, Henrik; Traerup Andersen, Jon

    2014-01-01

    Background. There is little knowledge regarding the characteristics of women treated with hypnotic benzodiazepine receptor agonists (HBRAs) during pregnancy. In this large Danish cohort study, we characterize women exposed to HBRA during pregnancy. We determined changes in prevalence of HBRA use from 1997 to 2010 and exposure to HBRAs in relation to pregnancy. Methods. We performed a retrospective cohort study including 911,017 pregnant women in the period from 1997 to 2010. Information was r...

  5. Development and validation of an EI-GC-MS method for the determination of benzodiazepine drugs and their metabolites in blood: applications in clinical and forensic toxicology.

    Science.gov (United States)

    Papoutsis, Ioannis I; Athanaselis, Sotirios A; Nikolaou, Panagiota D; Pistos, Constantinos M; Spiliopoulou, Chara A; Maravelias, Constantinos P

    2010-08-01

    Benzodiazepines are used widely in daily clinical practice, due to their multiple pharmacological actions. The frequent problems associated with the wide use of benzodiazepines, as well as the multiple incidents of poisonings, led to the necessity for the development of a precise, sensitive and rapid method for the simultaneous determination of the 23 most commonly used benzodiazepines (diazepam, nordiazepam, oxazepam, bromazepam, alprazolam, lorazepam, medazepam, flurazepam, fludiazepam, tetrazepam, chlordiazepoxide, clobazam, midazolam, flunitrazepam, 7-amino-flunitrazepam, triazolam, prazepam, nimetazepam, nitrazepam, temazepam, lormetazepam, clonazepam, camazepam) in blood. A gas chromatographic method combined with mass spectrometric detection was developed, optimized and validated for the determination of the above substances. This method includes liquid-liquid extraction with chloroform at pH 9 and two stages of derivatization using tetramethylammonium hydroxide and propyliodide (propylation), as well as a mixture of triethylamine:propionic anhydride (propionylation). The recoveries were higher than 74% for all the benzodiazepines. The calibration curves were linear within the dynamic range of each benzodiazepine with a correlation coefficient higher than 0.9981. The limits of detection and quantification for each analyte were statistically calculated from the relative calibration curves. Accuracy and precision were also calculated and were found to be less than 8.5% and 11.1%, respectively. The developed method was successfully applied for the investigation of both forensic and clinical toxicological cases of accidental and suicidal poisoning. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  6. Thermodynamic and NMR analyses of NADPH binding to lipocalin-type prostaglandin D synthase

    International Nuclear Information System (INIS)

    Qin, Shubin; Shimamoto, Shigeru; Maruno, Takahiro; Kobayashi, Yuji; Kawahara, Kazuki; Yoshida, Takuya; Ohkubo, Tadayasu

    2015-01-01

    Lipocalin-type prostaglandin D synthase (L-PGDS) is one of the most abundant proteins in human cerebrospinal fluid (CSF) with dual functions as a prostaglandin D_2 (PGD_2) synthase and a transporter of lipophilic ligands. Recent studies revealed that L-PGDS plays important roles in protecting against various neuronal diseases induced by reactive oxygen species (ROS). However, the molecular mechanisms of such protective actions of L-PGDS remain unknown. In this study, we conducted thermodynamic and nuclear magnetic resonance (NMR) analyses, and demonstrated that L-PGDS binds to nicotinamide coenzymes, including NADPH, NADP"+, and NADH. Although a hydrophilic ligand is not common for L-PGDS, these ligands, especially NADPH showed specific interaction with L-PGDS at the upper pocket of its ligand-binding cavity with an unusually bifurcated shape. The binding affinity of L-PGDS for NADPH was comparable to that previously reported for NADPH oxidases and NADPH in vitro. These results suggested that L-PGDS potentially attenuates the activities of NADPH oxidases through interaction with NADPH. Given that NADPH is the substrate for NADPH oxidases that play key roles in neuronal cell death by generating excessive ROS, these results imply a novel linkage between L-PGDS and ROS. - Highlights: • Interactions of L-PGDS with nicotinamide coenzymes were studied by ITC and NMR. • The binding affinity of L-PGDS was strongest to NADPH among nicotinamide coenzymes. • NADPH binds to the upper part of L-PGDS ligand-binding cavity. • L-PGDS binds to both lipophilic and hydrophilic ligands. • This study implies a novel linkage between L-PGDS and reactive oxygen species.

  7. Thermodynamic and NMR analyses of NADPH binding to lipocalin-type prostaglandin D synthase

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Shubin [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Shimamoto, Shigeru [Faculty of Science and Engineering, Kinki University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502 (Japan); Maruno, Takahiro; Kobayashi, Yuji [Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Kawahara, Kazuki; Yoshida, Takuya [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Ohkubo, Tadayasu, E-mail: ohkubo@phs.osaka-u.ac.jp [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2015-12-04

    Lipocalin-type prostaglandin D synthase (L-PGDS) is one of the most abundant proteins in human cerebrospinal fluid (CSF) with dual functions as a prostaglandin D{sub 2} (PGD{sub 2}) synthase and a transporter of lipophilic ligands. Recent studies revealed that L-PGDS plays important roles in protecting against various neuronal diseases induced by reactive oxygen species (ROS). However, the molecular mechanisms of such protective actions of L-PGDS remain unknown. In this study, we conducted thermodynamic and nuclear magnetic resonance (NMR) analyses, and demonstrated that L-PGDS binds to nicotinamide coenzymes, including NADPH, NADP{sup +}, and NADH. Although a hydrophilic ligand is not common for L-PGDS, these ligands, especially NADPH showed specific interaction with L-PGDS at the upper pocket of its ligand-binding cavity with an unusually bifurcated shape. The binding affinity of L-PGDS for NADPH was comparable to that previously reported for NADPH oxidases and NADPH in vitro. These results suggested that L-PGDS potentially attenuates the activities of NADPH oxidases through interaction with NADPH. Given that NADPH is the substrate for NADPH oxidases that play key roles in neuronal cell death by generating excessive ROS, these results imply a novel linkage between L-PGDS and ROS. - Highlights: • Interactions of L-PGDS with nicotinamide coenzymes were studied by ITC and NMR. • The binding affinity of L-PGDS was strongest to NADPH among nicotinamide coenzymes. • NADPH binds to the upper part of L-PGDS ligand-binding cavity. • L-PGDS binds to both lipophilic and hydrophilic ligands. • This study implies a novel linkage between L-PGDS and reactive oxygen species.

  8. Differential alterations of cortical glutamatergic binding sites in senile dementia of the Alzheimer type

    International Nuclear Information System (INIS)

    Chalmers, D.T.; Dewar, D.; Graham, D.I.; Brooks, D.N.; McCulloch, J.

    1990-01-01

    Involvement of cortical glutamatergic mechanisms in senile dementia of the Alzheimer type (SDAT) has been investigated with quantitative ligand-binding autoradiography. The distribution and density of Na(+)-dependent glutamate uptake sites and glutamate receptor subtypes--kainate, quisqualate, and N-methyl-D-aspartate--were measured in adjacent sections of frontal cortex obtained postmortem from six patients with SDAT and six age-matched controls. The number of senile plaques was determined in the same brain region. Binding of D-[3H]aspartate to Na(+)-dependent uptake sites was reduced by approximately 40% throughout SDAT frontal cortex relative to controls, indicating a general loss of glutamatergic presynaptic terminals. [3H]Kainate receptor binding was significantly increased by approximately 70% in deep layers of SDAT frontal cortex compared with controls, whereas this binding was unaltered in superficial laminae. There was a positive correlation (r = 0.914) between kainate binding and senile plaque number in deep cortical layers. Quisqualate receptors, as assessed by 2-amino-3-hydroxy-5-[3H]methylisoxazole-4-propionic acid binding, were unaltered in SDAT frontal cortex compared with controls. There was a small reduction (25%) in N-methyl-D-aspartate-sensitive [3H]glutamate binding only in superficial cortical layers of SDAT brains relative to control subjects. [3H]Glutamate binding in SDAT subjects was unrelated to senile plaque number in superficial cortical layers (r = 0.104). These results indicate that in the presence of cortical glutamatergic terminal loss in SDAT plastic alterations occur in some glutamate receptor subtypes but not in others

  9. Reduced post-synaptic serotonin type 1A receptor binding in bipolar depression

    Science.gov (United States)

    Nugent, Allison C.; Bain, Earle E.; Carlson, Paul J.; Neumeister, Alexander; Bonne, Omer; Carson, Richard E.; Eckelman, William; Herscovitch, Peter; Zarate, Carlos A.; Charney, Dennis S.; Drevets, Wayne C.

    2013-01-01

    Multiple lines of evidence suggest that serotonin type 1A (5-HT1A) receptor dysfunction is involved in the pathophysiology of mood disorders, and that alterations in 5-HT1A receptor function play a role in the mechanisms of antidepressant and mood stabilizer treatment. The literature is in disagreement, however, as to whether 5-HT1A receptor binding abnormalities exist in bipolar disorder (BD). We acquired PET images of 5-HT1A receptor binding in 26 unmedicated BD subjects and 37 healthy controls using [18F]FCWAY, a highly selective 5-HT1A receptor radio-ligand. The mean 5-HT1A receptor binding potential (BPP) was significantly lower in BD subjects compared to controls in cortical regions where 5-HT1A receptors are expressed post-synaptically, most prominently in the mesiotemporal cortex. Post-hoc assessments involving other receptor specific binding parameters suggested that this difference particularly affected the females with BD. The mean BPP did not differ between groups in the raphe nucleus, however, where 5-HT1A receptors are predominantly expressed pre-synaptically. Across subjects the BPP in the mesiotemporal cortex was inversely correlated with trough plasma cortisol levels, consistent with preclinical literature indicating that hippocampal 5-HT1A receptor expression is inhibited by glucocorticoid receptor stimulation. These findings suggest that 5-HT1A receptor binding is abnormally reduced in BD, and this abnormality may particularly involve the postsynaptic 5-HT1A receptor system of individuals with a tendency toward cortisol hypersecretion. PMID:23434290

  10. Introduction of lysine and clot binding properties in the kringle one domain of tissue-type plasminogen activator

    NARCIS (Netherlands)

    Bakker, A.H.F.; Greef, W. van der; Rehberg, E.F.; Marotti, K.R.; Verheijen, J.H.

    1993-01-01

    Despite the high overall similarity in primary structure between kringle one (K1) and kringle two (K2) of tissue-type plasminogen activator (t-PA) there exists an enormous functional difference. It is thought that, in contrast to K1, K2 mediates lysine binding and fibrin binding and is involved in

  11. Estrogen receptor-independent catechol estrogen binding activity: protein binding studies in wild-type, Estrogen receptor-alpha KO, and aromatase KO mice tissues.

    Science.gov (United States)

    Philips, Brian J; Ansell, Pete J; Newton, Leslie G; Harada, Nobuhiro; Honda, Shin-Ichiro; Ganjam, Venkataseshu K; Rottinghaus, George E; Welshons, Wade V; Lubahn, Dennis B

    2004-06-01

    Primary evidence for novel estrogen signaling pathways is based upon well-documented estrogenic responses not inhibited by estrogen receptor antagonists. In addition to 17beta-E2, the catechol estrogen 4-hydroxyestradiol (4OHE2) has been shown to elicit biological responses independent of classical estrogen receptors in estrogen receptor-alpha knockout (ERalphaKO) mice. Consequently, our research was designed to biochemically characterize the protein(s) that could be mediating the biological effects of catechol estrogens using enzymatically synthesized, radiolabeled 4-hydroxyestrone (4OHE1) and 4OHE2. Scatchard analyses identified a single class of high-affinity (K(d) approximately 1.6 nM), saturable cytosolic binding sites in several ERalphaKO estrogen-responsive tissues. Specific catechol estrogen binding was competitively inhibited by unlabeled catechol estrogens, but not by 17beta-E2 or the estrogen receptor antagonist ICI 182,780. Tissue distribution studies indicated significant binding differences both within and among various tissues in wild-type, ERalphaKO, and aromatase knockout female mice. Ligand metabolism experiments revealed extensive metabolism of labeled catechol estrogen, suggesting that catechol estrogen metabolites were responsible for the specific binding. Collectively, our data provide compelling evidence for the interaction of catechol estrogen metabolites with a novel binding protein that exhibits high affinity, specificity, and selective tissue distribution. The extensive biochemical characterization of this binding protein indicates that this protein may be a receptor, and thus may mediate ERalpha/beta-independent effects of catechol estrogens and their metabolites.

  12. Capacity for cooperative binding of thyroid hormone (T3) receptor dimers defines wild type T3 response elements.

    Science.gov (United States)

    Brent, G A; Williams, G R; Harney, J W; Forman, B M; Samuels, H H; Moore, D D; Larsen, P R

    1992-04-01

    Thyroid hormone response elements (T3REs) have been identified in a variety of promoters including those directing expression of rat GH (rGH), alpha-myosin heavy chain (rMHC), and malic enzyme (rME). A detailed biochemical and genetic analysis of the rGH element has shown that it consists of three hexamers related to the consensus [(A/G)GGT(C/A)A]. We have extended this analysis to the rMHC and rME elements. Binding of highly purified thyroid hormone receptor (T3R) to T3REs was determined using the gel shift assay, and thyroid hormone (T3) induction was measured in transient tranfections. We show that the wild type version of each of the three elements binds T3R dimers cooperatively. Mutational analysis of the rMHC and rME elements identified domains important for binding T3R dimers and allowed a direct determination of the relationship between T3R binding and function. In each element two hexamers are required for dimer binding, and mutations that interfere with dimer formation significantly reduce T3 induction. Similar to the rGH element, the rMHC T3RE contains three hexameric domains arranged as a direct repeat followed by an inverted copy, although the third domain is weaker than in rGH. All three are required for full function and T3R binding. The rME T3RE is a two-hexamer direct repeat T3RE, which also binds T3R monomer and dimer. Across a series of mutant elements, there was a strong correlation between dimer binding in vitro and function in vivo for rMHC (r = 0.99, P less than 0.01) and rME (r = 0.67, P less than 0.05) T3REs. Our results demonstrate a similar pattern of T3R dimer binding to a diverse array of hexameric sequences and arrangements in three wild type T3REs. Addition of nuclear protein enhanced T3R binding but did not alter the specificity of binding to wild type or mutant elements. Binding of purified T3R to T3REs was highly correlated with function, both with and without the addition of nuclear protein. T3R dimer formation is the common

  13. Study of manganese binding to the ferroxidase centre of human H-type ferritin.

    Science.gov (United States)

    Ardini, Matteo; Howes, Barry D; Fiorillo, Annarita; Falvo, Elisabetta; Sottini, Silvia; Rovai, Donella; Lantieri, Marco; Ilari, Andrea; Gatteschi, Dante; Spina, Gabriele; Chiancone, Emilia; Stefanini, Simonetta; Fittipaldi, Maria

    2018-05-01

    Ferritins are ubiquitous and conserved proteins endowed with enzymatic ferroxidase activity, that oxidize Fe(II) ions at the dimetal ferroxidase centre to form a mineralized Fe(III) oxide core deposited within the apo-protein shell. Herein, the in vitro formation of a heterodimetal cofactor constituted by Fe and Mn ions has been investigated in human H ferritin (hHFt). Namely, Mn and Fe binding at the hHFt ferroxidase centre and its effects on Fe(II) oxidation have been investigated by UV-Vis ferroxidation kinetics, fluorimetric titrations, multifrequency EPR, and preliminary Mössbauer spectroscopy. Our results show that in hHFt, both Fe(II) and Mn(II) bind the ferroxidase centre forming a Fe-Mn cofactor. Moreover, molecular oxygen seems to favour Mn(II) binding and increases the ferroxidation activity of the Mn-loaded protein. The data suggest that Mn influences the Fe binding and the efficiency of the ferroxidation reaction. The higher efficiency of the Mn-Fe heterometallic centre may have a physiological relevance in specific cell types (i.e. glia cells), where the concentration of Mn is the same order of magnitude as iron. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. Synthesis of iodine-123 labelled analogues of imidazenil and ethyl-imidazenil for studying benzodiazepine receptors using SPECT

    International Nuclear Information System (INIS)

    Katsifis, A.; Mattner, F.; Dikic, B.; Najdovski, L.; Kassiou, M.

    1996-01-01

    The [ 123 I]iodinated analogues of the benzodiazepine receptor partial agonist imidazenil and N-ethyl imidazenil have been synthesised for the study of the central benzodiazepine receptor using SPECT. [ 123 I]Iodomidazenil and [ 123 I]N-ethyliodoimidazenil were prepared by nucleophilic bromine-iodine exchange in acetic acid at 150 o . The products were purified by semi-preparative reverse-phase HPLC with average radiochemical yields of 80% in a total synthesis time of 80 minutes. The specific activity was determined to be greater than 2500 Ci/mmol. The radiochemical and chemical purity assessed by radio-TLC and HPLC were found to be 98%. Alternatively, iododestannylation reactions via the trimethyltin precursors with Na[ 123 I] in the presence of Chloramine-T or peracetic acid resulted in yields of only 20-25% with the bulk of activity being lost as volatile methyl [ 123 I]iodide. (author)

  15. A radioisotope dilution assay for unlabelled vitamin B12-intrinsic factor complex employing the binding intrinsic factor antibody: probable evidence for two types of binding antibody

    International Nuclear Information System (INIS)

    Jacob, E.; O'Brien, H.A.W.; Mollin, D.L.

    1977-01-01

    A new radioisotope dilution assay for vitamin B 12 -intrinsic factor complex is described. The method is based on the use of the binding type intrinsic antibody (the binding reagent), which when combined with the intrinsic factor-vitamin B 12 complex (labelled ligand), is quantitatively adsorbed onto zirconium phosphate gel pH 6.25. The new assay has been shown to provide a measure of intrinsic factor comparable with other intrinsic factor assays, but it has the important advantage of being able to measure the unlabelled vitamin B 12 -intrinsic factor complex (unlabelled ligand), and will, therefore, be valuable in the study of physiological events in the gastrointestinal tract. During the study, it was found that there is some evidence for at least two types of binding intrinsic factor antibody: One which combines preferentially with the intrinsic factor-vitamin B 12 complex and one which combines equally well with this complex or with free intrinsic factor. (author)

  16. Solid-phase extraction and on-disc derivatization of the major benzodiazepines in urine using enzyme hydrolysis and Toxi-Lab VC MP3 column.

    Science.gov (United States)

    King, J W; King, L J

    1996-01-01

    Because of the increase in use of the newer benzodiazepines, we explored the opportunity to develop a gas chromatographic-mass spectrometric (GC-MS) method that encompasses most of the widely prescribed benzodiazepines in use today. The benzodiazepines included in our study are nordiazepam, oxazepam, temazepam, lorazepam, alpha-hydroxyalprazolam, alpha-hydroxytriazolam, desalkylflurazepam, and 2-hydroxyethylflurazepam. Using 1.0 mL of urine as the matrix, we added the enzyme Glusulase and incubated the specimens for 2 h to obtain the free drugs. The hydrolyzed samples were then loaded onto a Toxi-Lab Spec VC MP3 column containing a 15-mg disc. On-disc derivatization was accomplished by adding N-methyl-N-(t-butyldimethylsilyl) trifluroacetamide (MTBSTFA) with 1% TBDMSCI to the disc. The derivatives were then placed in a GC vial and analyzed by GC-MS in the selected ion monitoring mode. These results were then compared to confirmed positives by the traditional acid hydrolysis GC-MS method.

  17. Structure-Aided Design of Novel Inhibitors of HIV Protease Based on a Benzodiazepine Scaffold

    Czech Academy of Sciences Publication Activity Database

    Schimer, Jiří; Cígler, Petr; Veselý, J.; Grantz Šašková, Klára; Lepšík, Martin; Brynda, Jiří; Řezáčová, Pavlína; Kožíšek, Milan; Císařová, I.; Oberwinkler, H.; Kraeusslich, H. G.; Konvalinka, Jan

    2012-01-01

    Roč. 55, č. 22 (2012), s. 10130-10135 ISSN 0022-2623 R&D Projects: GA ČR GBP208/12/G016; GA ČR GAP207/11/1798 Institutional research plan: CEZ:AV0Z40550506; CEZ:AV0Z50520514 Keywords : HIV protease inhibitor * rational drug design * 1,4-benzodiazepines Subject RIV: CE - Biochemistry Impact factor: 5.614, year: 2012

  18. A type IV pilus mediates DNA binding during natural transformation in Streptococcus pneumoniae.

    Directory of Open Access Journals (Sweden)

    Raphaël Laurenceau

    Full Text Available Natural genetic transformation is widely distributed in bacteria and generally occurs during a genetically programmed differentiated state called competence. This process promotes genome plasticity and adaptability in Gram-negative and Gram-positive bacteria. Transformation requires the binding and internalization of exogenous DNA, the mechanisms of which are unclear. Here, we report the discovery of a transformation pilus at the surface of competent Streptococcus pneumoniae cells. This Type IV-like pilus, which is primarily composed of the ComGC pilin, is required for transformation. We provide evidence that it directly binds DNA and propose that the transformation pilus is the primary DNA receptor on the bacterial cell during transformation in S. pneumoniae. Being a central component of the transformation apparatus, the transformation pilus enables S. pneumoniae, a major Gram-positive human pathogen, to acquire resistance to antibiotics and to escape vaccines through the binding and incorporation of new genetic material.

  19. Switch control pocket inhibitors of p38-MAP kinase. Durable type II inhibitors that do not require binding into the canonical ATP hinge region.

    Science.gov (United States)

    Ahn, Yu Mi; Clare, Michael; Ensinger, Carol L; Hood, Molly M; Lord, John W; Lu, Wei-Ping; Miller, David F; Patt, William C; Smith, Bryan D; Vogeti, Lakshminarayana; Kaufman, Michael D; Petillo, Peter A; Wise, Scott C; Abendroth, Jan; Chun, Lawrence; Clark, Robin; Feese, Michael; Kim, Hidong; Stewart, Lance; Flynn, Daniel L

    2010-10-01

    Switch control pocket inhibitors of p38-alpha kinase are described. Durable type II inhibitors were designed which bind to arginines (Arg67 or Arg70) that function as key residues for mediating phospho-threonine 180 dependant conformational fluxing of p38-alpha from an inactive type II state to an active type I state. Binding to Arg70 in particular led to potent inhibitors, exemplified by DP-802, which also exhibited high kinase selectivity. Binding to Arg70 obviated the requirement for binding into the ATP Hinge region. X-ray crystallography revealed that DP-802 and analogs induce an enhanced type II conformation upon binding to either the unphosphorylated or the doubly phosphorylated form of p38-alpha kinase. Copyright © 2010 Elsevier Ltd. All rights reserved.

  20. Risk factors associated with iatrogenic opioid and benzodiazepine withdrawal in critically ill pediatric patients: a systematic review and conceptual model.

    Science.gov (United States)

    Best, Kaitlin M; Boullata, Joseph I; Curley, Martha A Q

    2015-02-01

    Analgesia and sedation are common therapies in pediatric critical care, and rapid titration of these medications is associated with iatrogenic withdrawal syndrome. We performed a systematic review of the literature to identify all common and salient risk factors associated with iatrogenic withdrawal syndrome and build a conceptual model of iatrogenic withdrawal syndrome risk in critically ill pediatric patients. Multiple databases, including PubMed/Medline, EMBASE, CINAHL, and the Cochrane Central Registry of Clinical Trials, were searched using relevant terms from January 1, 1980, to August 1, 2014. Articles were included if they were published in English and discussed iatrogenic withdrawal syndrome following either opioid or benzodiazepine therapy in children in acute or intensive care settings. Articles were excluded if subjects were neonates born to opioid- or benzodiazepine-dependent mothers, children diagnosed as substance abusers, or subjects with cancer-related pain; if data about opioid or benzodiazepine treatment were not specified; or if primary data were not reported. In total, 1,395 articles were evaluated, 33 of which met the inclusion criteria. To facilitate analysis, all opioid and/or benzodiazepine doses were converted to morphine or midazolam equivalents, respectively. A table of evidence was developed for qualitative analysis of common themes, providing a framework for the construction of a conceptual model. The strongest risk factors associated with iatrogenic withdrawal syndrome include duration of therapy and cumulative dose. Additionally, evidence exists linking patient, process, and system factors in the development of iatrogenic withdrawal syndrome. Most articles were prospective observational or interventional studies. Given the state of existing evidence, well-designed prospective studies are required to better characterize iatrogenic withdrawal syndrome in critically ill pediatric patients. This review provides data to support the

  1. In vivo autoradiographic demonstration of β-adrenergic binding sites in adult rat type II alveolar epithelial cells

    International Nuclear Information System (INIS)

    Smith, D.M.; Sidhu, M.K.

    1984-01-01

    Adult male rats were injected intravenously with the muscarinic binding probe 3 H-Quinuclidinyl benzilate (QNB) or the β-adrenergic probe 3 H-dihydroalprenolol (DHA). Other rats were pre-treated with an intraperitoneal injection of a 500-fold excess of L-isoproterenol prior to the DHA. Light microscopic autoradiography of 0.5 μm sections of lung from the QNB group demonstrated very little labelling even after 6 months of exposure. In constrast, trachealis smooth muscle from these animals contained substantial labelling. Autoradiographs of lung from rats injected with DHA demonstrated labelling which was well localized over alveolar septa and concentrated over the cytoplasm of type II cells. Quantitative analysis of labelling in the DHA groups indicated a significant reduction of labelling in animals treated with L-isoproterenol prior to DHA, in both the alveolar parenchyma in general and over type II cells. The results of this study provide morphologic evidence for the uptake and specific binding of β-adrenergic antagonists by the adult lung in vivo, while failing to demonstrate similar binding of a muscarinic probe. In addition, the results demonstrate specific β-adrenergic receptors on type II cells in vivo and substantiate the view of a direct effect of β-adrenergic agonists on alveolar type II cells

  2. A simple method for the quantification of benzodiazepine receptors using iodine-123 iomazenil and single-photon emission tomography

    International Nuclear Information System (INIS)

    Ito, Hiroshi; Goto, Ryoui; Koyama, Masamichi; Kawashima, Ryuta; Ono, Shuichi; Sato, Kazunori; Fukuda, Hiroshi

    1996-01-01

    Iodine-123 iomazenil (Iomazenil) is a ligand for central type benzodiazepine receptors that is suitable for single-photon emission tomography (SPET). The purpose of this study was to develop a simple method for the quantification of its binding potential (BP). The method is based on a two-compartment model (K 1 , influx rate constant; k 2 ', efflux rate constant; V T '(=K 1 /k 2 '), the total distribution volumes relative to the total arterial tracer concentration), and requires two SPET scans and one blood sampling. For a given input function, the radioactivity ratio of the early to delayed scans can be considered to tabulate as a function of k 2 ', and a table lookup procedure provides the corresponding k 2 ' value, from which K 1 and V t ' values are then calculated. The arterial input function is obtained by calibration of the standard input function by the single blood sampling. SPET studies were performed on 14 patients with cerebrovascular diseases, dementia or brain tumours (mean age ±SD, 56.0±12.2). None of the patients had any heart, renal or liver disease. A dynamic SPET scan was performed following intravenous bolus injection of Iomazenil. A static SPET scan was performed at 180 min after injection. Frequent blood sampling from the brachial artery was performed on all subjects for determination of the arterial input function. Two-compartment model analysis was validated for calculation of the V T ' value of Iomazenil. Good correlations were observed between V T ' values calculated by three-compartment model analysis and those calculated by the present method, in which the scan time combinations (early scan/delayed scan) used were 15/180 min, 30/180 min or 45/180 min (all combinations: r=0.92), supporting the validity of this method. The present method is simple and applicable for clinical use. (orig.)

  3. The binding of [3H]AF-DX 384 to rat ileal smooth muscle muscarinic receptors

    International Nuclear Information System (INIS)

    Entzeroth, M.; Mayer, N.

    1991-01-01

    The tritiated cardioselective muscarinic antagonist AF-DX 384 (5,11-dihydro-11-[2-[-(8-dipropylamino)methyl]-1-piperidinyl-ethyl-amino-carbonyl]-6H-pyrido [2,3-b] [1,4]benzodiazepin-6-one) was used to label muscarinic receptors in the rat ileum. Saturation binding to membrane suspensions revealed a high affinity binding site with a Kd of 9.2 nM. The maximal number of binding sites labeled in this tissue (Bmax) is 237 fmol/mg protein. The association and dissociation kinetics were well represented by single exponential reactions, and the dissociation constant obtained from the ratio of rate constants was in agreement with that derived from saturation experiments. Specific binding was inhibited by muscarinic antagonists with a rank order of potencies of atropine (pKi: 8.80) greater than 4-DAMP (pKi: 8.23) = AF-DX 384 (pKi: 8.20) greater than AF-DX 116 (pKi: 7.09) = hexahydro-sila-difenidol (pKi: 6.97) greater than pirenzepine (pKi: 6.49) and is consistent with the interaction of [3H]AF-DX 384 with muscarinic receptors of the M2 subtype. It can be concluded that [3H]AF-DX 384 can be used to selectively label M2 muscarinic receptors in heterogeneous receptor populations

  4. Effect of mirtazapine versus selective serotonin reuptake inhibitors on benzodiazepine use in patients with major depressive disorder: a pragmatic, multicenter, open-label, randomized, active-controlled, 24-week trial.

    Science.gov (United States)

    Hashimoto, Tasuku; Shiina, Akihiro; Hasegawa, Tadashi; Kimura, Hiroshi; Oda, Yasunori; Niitsu, Tomihisa; Ishikawa, Masatomo; Tachibana, Masumi; Muneoka, Katsumasa; Matsuki, Satoshi; Nakazato, Michiko; Iyo, Masaomi

    2016-01-01

    This study aimed to evaluate whether selecting mirtazapine as the first choice for current depressive episode instead of selective serotonin reuptake inhibitors (SSRIs) reduces benzodiazepine use in patients with major depressive disorder (MDD). We concurrently examined the relationship between clinical responses and serum mature brain-derived neurotrophic factor (BDNF) and its precursor, proBDNF. We conducted an open-label randomized trial in routine psychiatric practice settings. Seventy-seven MDD outpatients were randomly assigned to the mirtazapine or predetermined SSRIs groups, and investigators arbitrarily selected sertraline or paroxetine. The primary outcome was the proportion of benzodiazepine users at weeks 6, 12, and 24 between the groups. We defined patients showing a ≥50 % reduction in Hamilton depression rating scale (HDRS) scores from baseline as responders. Blood samples were collected at baseline, weeks 6, 12, and 24. Sixty-five patients prescribed benzodiazepines from prescription day 1 were analyzed for the primary outcome. The percentage of benzodiazepine users was significantly lower in the mirtazapine than in the SSRIs group at weeks 6, 12, and 24 (21.4 vs. 81.8 %; 11.1 vs. 85.7 %, both P  depressive episodes may reduce benzodiazepine use in patients with MDD. Trial registration UMIN000004144. Registered 2nd September 2010. The date of enrolment of the first participant to the trial was 24th August 2010. This study was retrospectively registered 9 days after the first participant was enrolled.

  5. Simultaneous identification of abused drugs, benzodiazepines, and new psychoactive substances in urine by liquid chromatography tandem mass spectrometry

    Directory of Open Access Journals (Sweden)

    Hei-Hwa Lee

    2016-03-01

    Full Text Available A literature search reveals no studies concerning simultaneous identification of commonly abused drugs, benzodiazepines, and new psychoactive substances in urine by liquid chromatography tandem mass spectrometry (LC–MS/MS. We developed and validated an LC–MS/MS method for simultaneous identification of multiple abused drugs, benzodiazepines, and new psychoactive substances in urine from suspected drug abusers. The instrument was operated in multiple-reaction monitoring using an electrospray ionization mode. Chromatograms were separated using an ACE5 C18 column on a gradient of acetonitrile. After liquid–liquid extraction, samples were passed through a 0.22-μm polyvinylidene difluoride filter before injection into the LC–MS/MS. The limits of quantitation ranged from 0.5 ng/mL to 31.3 ng/mL. The linearity ranged from 0.5 ng/mL to 200 ng/mL. The precision results were below 15.4% (intraday and 18.7% (interday. The intraday accuracy ranged from 85.9% to 121.0%; interday accuracy ranged from 66.1% to 128.7%. The proposed method was applied to 769 urine samples. The most common three drugs identified were ketamine, amphetamine, and opiates. The drug positive rate for one or more drugs was 79.6%. Our results demonstrate the suitability of the LC–MS/MS method for simultaneous identification of multiple abused drugs, benzodiazepines, and new psychoactive substances in urine.

  6. Radiosynthesis and in vivo evaluation of N-[{sup 11}C]methylated imidazopyridineacetamides as PET tracers for peripheral benzodiazepine receptors

    Energy Technology Data Exchange (ETDEWEB)

    Sekimata, Katsuhiko [Department of Brain Sciences and Molecular Imaging, National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, Obu, Aichi 474-8522 (Japan); Hatano, Kentaro [Department of Brain Sciences and Molecular Imaging, National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, Obu, Aichi 474-8522 (Japan)], E-mail: hatanok@nils.go.jp; Ogawa, Mikako [Photon Medical Research Center, Hamamatsu University School of Medicine, Shizuoka 431-3192 Japan (Japan); Abe, Junichiro [Department of Brain Sciences and Molecular Imaging, National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, Obu, Aichi 474-8522 (Japan); Magata, Yasuhiro [Photon Medical Research Center, Hamamatsu University School of Medicine, Shizuoka 431-3192 Japan (Japan); Biggio, Giovanni; Serra, Mariangela [Department of Experimental Biology, University of Cagliari, Cagliari 09100 (Italy); Laquintana, Valentino; Denora, Nunzio; Latrofa, Andrea; Trapani, Giuseppe; Liso, Gaetano [Pharmaco-Chemistry Department, University of Bari, Bari 70125 (Italy); Ito, Kengo [Department of Brain Sciences and Molecular Imaging, National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, Obu, Aichi 474-8522 (Japan)

    2008-04-15

    Imidazopyridineacetoamide 5-8, a series of novel and potentially selective peripheral benzodiazepine receptor (PBR) ligands with affinities comparable to those of known PBR ligands, was investigated. Radiosyntheses of [{sup 11}C]5, 6, 7 or 8 was accomplished by N-methylation of the corresponding desmethyl precursors with [{sup 11}C]methyl iodide in the presence of NaH in dimethylformamide (DMF), resulting in 25% to 77% radiochemical yield and specific activitiy of 20 to 150 MBq/nmol. Each of the labeled compounds was injected in ddY mice, and the radioactivity and weight of dissected peripheral organs and brain regions were measured. Organ distribution of [{sup 11}C]7 was consistent with the known PBR distribution. Moreover, [{sup 11}C]7 showed the best combination of brain uptake and PBR binding, leading to its high retention in the olfactory bulb and cerebellum, areas where PBR density is high in mouse brain. Coinjection of PK11195 or unlabeled 7 significantly reduced the brain uptake of [{sup 11}C]7. These results suggest that [{sup 11}C]7 could be a useful radioligand for positron emission tomography imaging of PBRs.

  7. The role of the lysyl binding site of tissue-type plasminogen activator in the interaction with a forming fibrin clot

    NARCIS (Netherlands)

    Bakker, A.H.F.; Weening-Verhoeff, E.J.D.; Verheijen, J.H.

    1995-01-01

    To describe the role of the lysyl binding site in the interaction of tissue-type plasminogen activator (t-PA, FGK1K2P) with a forming fibrin clot, we performed binding experiments with domain deletion mutants GK1K2P, K2P, and the corresponding point mutants lacking the lysyl binding site in the

  8. Therapeutic response to benzodiazepine in panic disorder subtypes

    Directory of Open Access Journals (Sweden)

    Alexandre Martins Valença

    Full Text Available CONTEXT: This study makes a comparison between two subtypes of panic disorder regarding the clinical efficacy of clonazepam, a benzodiazepine. OBJECTIVES: To evaluate the clinical efficacy of clonazepam in a fixed dosage (2 mg/day, compared to placebo, in the treatment of panic disorder patients and to verify whether there are any differences in the responses to clonazepam between panic disorder patients with the respiratory and non-respiratory subtypes. TYPE OF STUDY: Randomized study with clonazepam and placebo. SETTING: Outpatient Anxiety and Depression Unit of the Institute of Psychiatry, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil. PARTICIPANTS: 34 patients with a diagnosis of panic disorder with agoraphobia, between 18 and 55 years old. PROCEDURES: Administration of clonazepam or placebo for 6 weeks, in panic disorder patients, after they were classified within two subtypes of panic disorder: respiratory and non-respiratory. MAIN MEASUREMENTS: Changes in the number of panic attacks in comparison with the period before the beginning of the study; Hamilton Anxiety Scale; Global Clinical Impression Scale; and Patient's Global Impression scale. RESULTS: In the group that received clonazepam, by the end of the 6th week there was a statistically significant clinical improvement, shown by the remission of panic attacks (p < 0.001 and decrease in anxiety (p = 0.024. In the group that received clonazepam there was no significant difference between the respiratory and non-respiratory subtypes of panic disorder, regarding the therapeutic response to clonazepam. CONCLUSION: Clonazepam was equally effective in the treatment of the respiratory and non-respiratory subtypes of panic disorder, suggesting there is no difference in the therapeutic response between the two subtypes.

  9. Ring rearrangements and reactivity of 3-((4-oxo-4H-chromen-3-ylmethylene-4-phenyl-1H-[1,5]benzodiazepin-2(3H-one toward some nucleophiles

    Directory of Open Access Journals (Sweden)

    Hanan Salah

    2017-05-01

    Full Text Available Condensation of 4-phenyl-1H-[1,5]benzodiazepin-2(3H-one (1 with 3-formylchromone (2 afforded a mixture of 3-(chromenylmethylene[1,5]benzodiazepinone 3 and 14-chromenylbenzodiazepino[2,3:6,5]pyrano[2,3-b]benzodiazepine 4. Ring rearrangements of compound 3 with different nucleophilic reagents, such as potassium hydroxide and/or ammonium acetate led to rearrangement into pyranobenzodiazepine 5 and pyridobenzodiazepine 6, respectively. Treatment of compound 3 with hydrazine hydrate, hydroxylamine hydrochloride, malononitrile, cyanothioacetamide, 2-cyano-3,3-disufanylacrylonitrile, and/or 2-cyano-3-phenylamino-3-sufanylacrylonitrile, has been carried out at different conditions, leading to versatile heterocyclic substituted benzodiazepines at position 3, viz. pyrazole 8, isoxazole 9, pyridines 10 and 11, 1,3-dithiine 12, and 1,3-thiazine 13 derivatives.

  10. Evidence that kidney function but not type 2 diabetes determines retinol-binding protein 4 serum levels

    DEFF Research Database (Denmark)

    Henze, Andrea; Frey, Simone K; Raila, Jens

    2008-01-01

    It has been suggested that retinol-binding protein 4 (RBP4) links adiposity, insulin resistance, and type 2 diabetes. However, circulating RBP4 levels are also affected by kidney function. Therefore, the aim of this study was to test whether RBP4 serum levels are primarily associated with kidney...... function or type 2 diabetes....

  11. Characterization of tissue plasminogen activator binding proteins isolated from endothelial cells and other cell types

    International Nuclear Information System (INIS)

    Beebe, D.P.; Wood, L.L.; Moos, M.

    1990-01-01

    Human tissue plasminogen activator (t-PA) was shown to bind specifically to human osteosarcoma cells (HOS), and human epidermoid carcinoma cells (A-431 cells). Crosslinking studies with DTSSP demonstrated high molecular weight complexes (130,000) between 125 I-t-PA and cell membrane protein on human umbilical vein endothelial cells (HUVEC), HOS, and A-431 cells. A 48-65,000 molecular weight complex was demonstrated after crosslinking t-PA peptide (res. 7-20) to cells. Ligand blotting of cell lysates which had been passed over a t-PA affinity column revealed binding of t-PA to 54,000 and 95,000 molecular weight proteins. Several t-PA binding proteins were identified in immunopurified cell lysates, including tubulin beta chain, plasminogen activator inhibitor type 1 and single chain urokinase

  12. Differential induction of progestin-binding sites in uterine cell types by estrogen and antiestrogen

    International Nuclear Information System (INIS)

    Ennis, B.W.; Stumpf, W.E.

    1988-01-01

    Effects of antiestrogen on progestin binding in uterine cell types were determined and compared to those of estrogen. Effects on uterine morphology were also studied. Immature rats were treated with four daily sc injections of 100 micrograms hydroxytamoxifen [TAM(OH)], 5 micrograms estradiol (E2), or oil. On day 5 the rats were injected iv with 1 microgram of the synthetic progestin [ 3 H]Org 2058, and 1 h later uteri were excised, weighed, and processed for thaw-mount autoradiography. Treatment with TAM(OH) or E2 resulted in uterine weight gain, which was greater in animals treated with E2. E2 treatment resulted in cellular hypertrophy in all tissue compartments, especially in the luminal epithelium and myometrium, but TAM(OH) treatment resulted in hypertrophy of only the luminal epithelium. Treatment with TAM(OH) or E2 changed the pattern and intensity of nuclear binding of [ 3 H]Org 2058 from that in oil-treated controls. E2 increased progestin binding in stroma and myometrium and decreased it in luminal epithelium. TAM(OH), similarly, decreased progestin binding in the luminal epithelium and increased it, albeit less than E2, in the myometrium, but left it unchanged in the stroma. The results indicate that E2 and TAM(OH) differentially effect progestin binding among the uterine tissue compartments

  13. Comparison of cerebral blood flow and metabolism to flumazenil binding potential in patients with hemodynamic ischemia

    International Nuclear Information System (INIS)

    Yukawa, Hirotsugu; Ogasawara, Kuniaki

    2003-01-01

    Because benzodiazepine receptors (BZR) are abundant in the cortex, an accumulation of 11 C-flumazenil which selectively bind to BZR may be useful as markers of neuron density. The aims of this study were to clarify the relationship between neuron density and cerebral oxygen metabolism and to investigate the usefulness of 11 C-flumazenil PET for detecting misery perfusion. The subjects were 16 patients with either internal carotid or middle cerebral arterial occlusive disease who underwent PET. Regional cerebral blood flow (CBF), regional cerebral oxygen extraction fraction (OEF), regional cerebral metabolic rate for oxygen (CMRO 2 ) and regional cerebrovascular reserve capacity (CVRC) to acetazolamide were calculated. After CBF study, flumazenil binding potential was measured using the [ 11 C] flumazenil bolus injection method. Forty-eight regions of interests (ROIs) were obtained in 16 patients. Flumazenil binding potential was correlated to CMRO 2 (r=0.337, p=0.0069), but in 7 of 48 ROIs, CMRO 2 decreased, whereas flumazenil binding potential did not change. Seventeen of 29 ROIs with decreased CVRC showed high OEF and the remaining 12 showed normal OEF. Flumazenil binding potential in ROIs with normal OEF was significantly lower than in those with high OEF (p=0.0003). This study demonstrated that 11 C-flumazenil PET is useful for detecting misery perfusion in patients with hemodynamic ischemia. (author)

  14. Microwave assisted facile one pot synthesis of novel 5-carboxamido substituted analogues of 1,4-benzodiazepin-2-one of medicinal interest

    Directory of Open Access Journals (Sweden)

    R. Sirohi

    2013-05-01

    Full Text Available A novel synthetic approach developed by the use of a microwave (MW assisted one pot protocol to the synthesis of methyl-1,4-benzodiazepin-2-one-5-carboxylate (2 derivatives for which N-chloroacetylisatin was employed with an elegant success to afford the formation of 5-methyl carboxylate derivatives of 1,4-benzodiazepines from its reaction with methanolic hexamine. We have utilized MW technique in the present work in conducting the reaction of carboxylate ester derivative (2 with several selected primary and secondary amines 3, 4, 5, 6, 7, and 8 which had the previous history of being biologically active in the literature, to generate the corresponding carboxamide derivatives (9-14.

  15. Photoconversion and fluorescence properties of a red/green-type cyanobacteriochrome AM1_C0023g2 that binds not only phycocyanobilin but also biliverdin.

    Directory of Open Access Journals (Sweden)

    Keiji eFushimi

    2016-04-01

    Full Text Available Cyanobacteriochromes (CBCRs are distantly related to the red/far-red responsive phytochromes. Red/green-type CBCRs are widely distributed among various cyanobacteria. The red/green-type CBCRs covalently bind phycocyanobilin (PCB and show red/green reversible photoconversion. Recent studies revealed that some red/green-type CBCRs from chlorophyll d-bearing cyanobacterium Acaryochloris marina covalently bind not only PCB but also biliverdin (BV. The BV-binding CBCRs show far-red/orange reversible photoconversion. Here, we identified another CBCR (AM1_C0023g2 from A. marina that also covalently binds not only PCB but also BV with high binding efficiencies, although BV chromophore is unstable in the presence of urea. Replacement of Ser334 with Gly resulted in significant improvement in the yield of the BV-binding holoprotein, thereby ensuring that the mutant protein is a fine platform for future development of optogenetic switches. We also succeeded in detecting near-infrared fluorescence from mammalian cells harboring PCB-binding AM1_C0023g2 whose fluorescence quantum yield is 3.0%. Here the PCB-binding holoprotein is shown as a platform for future development of fluorescent probes.

  16. Alterations in brain-derived neurotrophic factor in the mouse hippocampus following acute but not repeated benzodiazepine treatment.

    Directory of Open Access Journals (Sweden)

    Stephanie C Licata

    Full Text Available Benzodiazepines (BZs are safe drugs for treating anxiety, sleep, and seizure disorders, but their use also results in unwanted effects including memory impairment, abuse, and dependence. The present study aimed to reveal the molecular mechanisms that may contribute to the effects of BZs in the hippocampus (HIP, an area involved in drug-related plasticity, by investigating the regulation of immediate early genes following BZ administration. Previous studies have demonstrated that both brain derived neurotrophic factor (BDNF and c-Fos contribute to memory- and abuse-related processes that occur within the HIP, and their expression is altered in response to BZ exposure. In the current study, mice received acute or repeated administration of BZs and HIP tissue was analyzed for alterations in BDNF and c-Fos expression. Although no significant changes in BDNF or c-Fos were observed in response to twice-daily intraperitoneal (i.p. injections of diazepam (10 mg/kg + 5 mg/kg or zolpidem (ZP; 2.5 mg/kg + 2.5 mg/kg, acute i.p. administration of both triazolam (0.03 mg/kg and ZP (1.0 mg/kg decreased BDNF protein levels within the HIP relative to vehicle, without any effect on c-Fos. ZP specifically reduced exon IV-containing BDNF transcripts with a concomitant increase in the association of methyl-CpG binding protein 2 (MeCP2 with BDNF promoter IV, suggesting that MeCP2 activity at this promoter may represent a ZP-specific mechanism for reducing BDNF expression. ZP also increased the association of phosphorylated cAMP response element binding protein (pCREB with BDNF promoter I. Future work should examine the interaction between ZP and DNA as the cause for altered gene expression in the HIP, given that BZs can enter the nucleus and intercalate into DNA directly.

  17. Synthesis, biological evaluation, and structure-activity relationship of clonazepam, meclonazepam, and 1,4-benzodiazepine compounds with schistosomicidal activity.

    Science.gov (United States)

    Menezes, Carla M S; Rivera, Gildardo; Alves, Marina A; do Amaral, Daniel N; Thibaut, Jean Pierre B; Noël, François; Barreiro, Eliezer J; Lima, Lídia M

    2012-06-01

    The inherent morbidity and mortality caused by schistosomiasis is a serious public health problem in developing countries. Praziquantel is the only drug in therapeutic use, leading to a permanent risk of parasite resistance. In search for new schistosomicidal drugs, meclonazepam, the 3-methyl-derivative of clonazepam, is still considered an interesting lead-candidate because it has a proven schistosomicidal effect in humans but adverse effects on the central nervous system did not allow its clinical use. Herein, the synthesis, in vitro biological evaluation, and molecular modeling of clonazepam, meclonazepam, and analogues are reported to establish the first structure-activity relationship for schistosomicidal benzodiazepines. Our findings indicate that the amide moiety [N(1) H-C(2) (=O)] is the principal pharmacophoric unit of 1,4-benzodiazepine schistosomicidal compounds and that substitution on the amide nitrogen atom (N(1) position) is not tolerated. © 2012 John Wiley & Sons A/S.

  18. Exhaustive sampling of docking poses reveals binding hypotheses for propafenone type inhibitors of P-glycoprotein.

    Directory of Open Access Journals (Sweden)

    Freya Klepsch

    2011-05-01

    Full Text Available Overexpression of the xenotoxin transporter P-glycoprotein (P-gp represents one major reason for the development of multidrug resistance (MDR, leading to the failure of antibiotic and cancer therapies. Inhibitors of P-gp have thus been advocated as promising candidates for overcoming the problem of MDR. However, due to lack of a high-resolution structure the concrete mode of interaction of both substrates and inhibitors is still not known. Therefore, structure-based design studies have to rely on protein homology models. In order to identify binding hypotheses for propafenone-type P-gp inhibitors, five different propafenone derivatives with known structure-activity relationship (SAR pattern were docked into homology models of the apo and the nucleotide-bound conformation of the transporter. To circumvent the uncertainty of scoring functions, we exhaustively sampled the pose space and analyzed the poses by combining information retrieved from SAR studies with common scaffold clustering. The results suggest propafenone binding at the transmembrane helices 5, 6, 7 and 8 in both models, with the amino acid residue Y307 playing a crucial role. The identified binding site in the non-energized state is overlapping with, but not identical to, known binding areas of cyclic P-gp inhibitors and verapamil. These findings support the idea of several small binding sites forming one large binding cavity. Furthermore, the binding hypotheses for both catalytic states were analyzed and showed only small differences in their protein-ligand interaction fingerprints, which indicates only small movements of the ligand during the catalytic cycle.

  19. A New Terminal Cyano Group-containing Benzodiazepine Alkaloid from the Mangrove Endophytic Fungus Penicillium sp. .

    Science.gov (United States)

    Li, Jing; Zhong, Yi-sheng; Yuan, Jie; Zhu, Xun; Lu, Yong-jun; Lin, Yong-cheng; Liu, Lan

    2015-09-01

    A new benzodiazepine alkaloid containing terminal cyano group has been isolated from a mangrove endophytic fungus, Penicillium 299#. Structure elucidation was determined by 1D and 2D NMR spectroscopy and the absolute configuration was determined by electronic circular dichroism (ECD). The new compound showed no cytotoxic activities in vitro against human cancer lines MDA-MB-435, HepG2, HCT-116, and Calu-3.

  20. AHR-11797: a novel benzodiazepine antagonist

    International Nuclear Information System (INIS)

    Johnson, D.N.; Kilpatrick, B.F.; Hannaman, P.K.

    1986-01-01

    AHR-11797(5,6-dihydro-6-methyl-1-phenyl- 3 H-pyrrolo[3,2,1-ij]quinazolin-3-one) displaced 3 H-flunitrazepam (IC 50 = 82 nM) and 3 H-Ro 15-1877 (IC 50 = 104 nM) from rat brain synaptosomes. AHR-11797 did not protect mice from seizures induced by maximal electroshock or subcutaneous Metrazol (scMET), nor did it induce seizures in doses up to the lethal dose. However, at 31.6 mg/kg, IP, it significantly increased the anticonvulsant ED 50 of chlordiazepoxide (CDPX) from 1.9 to 31.6 mg/kg, IP. With 56.7 mg/kg, IP, of AHR-11797, CDPX was inactive in doses up to 100 mg/kg, IP. AHR-11797 did not significantly increase punished responding in the Geller and Seifter conflict procedure, but it did attenuate the effects of diazepam. Although the compound is without anticonvulsant or anxiolytic activity, it did have muscle relaxant properties. AHR-11797 blocked morphine-induced Straub tail in mice (ED 50 = 31 mg/kg, IP) and it selectively suppressed the polysnaptic linguomandibular reflex in barbiturate-anesthetized cats. The apparent muscle relaxant activity of AHR-11797 suggests that different receptor sites are involved for muscle relaxant vs. anxiolytic/anticonvulsant activities of the benzodiazepines

  1. Functional characterization of the 1,5-benzodiazepine clobazam and its major active metabolite N-desmethylclobazam at human GABAA receptors expressed in Xenopus laevis oocytes

    DEFF Research Database (Denmark)

    Hammer, Harriet; Ebert, Bjarke; Jensen, Henrik S.

    2015-01-01

    different in vivo adverse effects and addiction liability profile than the classic 1,4-benzodiazepines. In this study, it was investigated whether the in vitro pharmacological properties of clobazam and its major active metabolite N-desmethylclobazam could explain some of these clinical differences...... by the 1,4-benzodiazepine clonazepam. All three compounds potentiated GABA EC20-evoked responses through the α1,2,3,5β2γ2S GABAARs in a reversible and concentration-dependent manner, with each displaying similar EC50 values at the four subtypes. Furthermore, the degrees of potentiation of the GABA EC20...

  2. Purification and characterization of a new type lactose-binding Ulex europaeus lectin by affinity chromatography.

    Science.gov (United States)

    Konami, Y; Yamamoto, K; Osawa, T

    1991-02-01

    A new type lactose-binding lectin was purified from extracts of Ulex europaeus seeds by affinity chromatography on a column of galactose-Sepharose 4B, followed by gel filtration on Sephacryl S-300. This lectin, designated as Ulex europaeus lectin III (UEA-III), was found to be inhibited by lactose. The dimeric lectin is a glycoprotein with a molecular mass of 70,000 Da; it consists of two apparently identical subunits of a molecular mass of 34,000 Da. Compositional analysis showed that this lectin contains 30% carbohydrate and a large amount of aspartic acid, serine and valine, but no sulfur-containing amino acids. The N-terminal amino-acid sequences of L-fucose-binding Ulex europaeus lectin I (UEA-I) and di-N-acetylchitobiose-binding Ulex europaeus lectin II (UEA-II), both of which we have already purified and characterized, and that of UEA-III were determined and compared.

  3. Benzodiazepine receptor ligand influences on learning: an endogenous modulatory mechanism mediated by benzodiazepines possibly of alimentary origin

    Directory of Open Access Journals (Sweden)

    I. Izquierdo

    1991-01-01

    Full Text Available In rats pre-but not post-training ip administration of either flumazenil, a central benzodiazepine (BSD receptor antagonist, or of n-butyl-B-carboline-carboxylate (BCCB, an inverse agonist, enhanced retention of inhibitory avoidance learning. Flumazenil vlocked the enhancing effect of BCCB, and the inhibitory effect of the BZD agonists clonazepam and diazepam also given pre-training. Post-training administration of these drugs had no effects. The peripheral BZD receptor agonist/chloride channel blocker Ro5-4864 had no effect on the inhibitory avoidance task when given ip prior to training, buth it caused enhancement when given immediately post-training either ip or icv. This effect was blocked by PK11195, a competitive antagonist of Ro5-4864. These results suggest that ther is an endogenous mechanism mediated by BZD agonists, which is sensitive to inverse agonists and that normally down-regulates the formation of memories through a mechanism involving GABA-A receptors and the corresponding chloride channels. The most likely agonists for the endogenous mechanism suggested are the diazepam-like BZDs found in brain whose origin is possibly alimentary. Levels of these BZDs in the cortex were found to sharply decrease after inhibitory acoidance training or mere exposure to the training apparatus.

  4. CYP2C9 Genotypes Modify Benzodiazepine-Related Fall Risk: Original Results From Three Studies With Meta-Analysis

    NARCIS (Netherlands)

    Ham, Annelies C.; Ziere, Gijsbertus; Broer, Linda; Swart, Karin M. A.; Enneman, Anke W.; van Dijk, Suzanne C.; van Wijngaarden, Janneke P.; van der Zwaluw, Nikita L.; Brouwer-Brolsma, Elske M.; Dhonukshe-Rutten, Rosalie A. M.; van Schoor, Natasja M.; Zillikens, M. Carola; van Gelder, Teun; de Vries, Oscar J.; Lips, Paul; Deeg, Dorly J. H.; de Groot, Lisette C. P. G. M.; Hofman, Albert; Witkamp, Renger F.; Uitterlinden, André G.; Stricker, Bruno H.; van der Velde, Nathalie

    2017-01-01

    To investigate whether the CYP2C9*2 and *3 variants modify benzodiazepine-related fall risk. Three prospective studies; the Rotterdam Study, B-PROOF, and LASA. Community-dwelling individuals living in or near five Dutch cities. There were 11,485 participants aged ≥55 years. Fall incidents were

  5. Pharmacological and biochemical properties of the benzodiazepine-GABA receptor in codfish brain in comparison with mammalian brain

    International Nuclear Information System (INIS)

    Deng, L.

    1989-01-01

    The GABA receptor of codfish brain is encoded by an ancestral gene of the mammalian GABA receptor based on phylogenetic studies. The mammalian GABA receptor consists of at least two subunits (β and α) which could be photoaffinity labeled by the GABA agonist [ 3 H]muscimol (57 kDa) and the benzodiazepine (BZ) agonist [ 3 H]flunitrazepam (52 kDa), respectively. In contrast, electrophoresis of codfish GABA receptor photoaffinity labeled by the same ligands showed a single radioactive peak on sodium dodecyl surface polyarcylamide gel, giving rise to a relative molecular weight of 56-57 kDa equivalent to the β subunit of 57 kDa in mammals. The homogeneity of purified receptor using benzodiazepine (Ro 7-1986/1) affinity chromatography was further verified by two-dimensional gel electrophoresis based on isoelectric point and molecular weight, in addition to a single band on a silver stained gel and specific activity. The receptor density and affinity constant for [ 3 H]muscimol and [ 3 H]flunitrazepam are comparable to those in bovine, rate, and human brain

  6. Convulsions induced by centrally administered NMDA in mice: effects of NMDA antagonists, benzodiazepines, minor tranquilizers and anticonvulsants.

    Science.gov (United States)

    Moreau, J. L.; Pieri, L.; Prud'hon, B.

    1989-01-01

    1. Convulsions were induced reproducibly by intracerebroventricular injection of N-methyl-D-aspartic acid (NMDA) to conscious mice. 2. Competitive (carboxypiperazine-propylphosphonic acid, CPP; 2-amino-7-phosphonoheptanoic acid, AP7) and non-competitive (MK801; phencyclidine, PCP; thienylcyclohexylpiperidine, TCP; dextrorphan; dextromethorphan) NMDA antagonists prevented NMDA-induced convulsions. 3. Benzodiazepine receptor agonists and partial agonists (triazolam, diazepam, clonazepam, Ro 16-6028), classical anticonvulsants (diphenylhydantoin, phenobarbitone, sodium valproate) and meprobamate were also found to prevent NMDA-induced convulsions. 4. Flumazenil (a benzodiazepine receptor antagonist) and the GABA agonists THIP and muscimol (up to subtoxic doses) were without effect. 5. Flumazenil reversed the anticonvulsant action of diazepam, but not that of MK801. 6. Results obtained in this model differ somewhat from those described in a seizure model with systemic administration of NMDA. An explanation for this discrepancy is offered. 7. This model is a simple test for assessing the in vivo activity of NMDA antagonists and also expands the battery of chemically-induced seizure models for characterizing anticonvulsants not acting at NMDA receptors. PMID:2574061

  7. Importance of chemical binding type between As and iron-oxide on bioaccessibility in soil: Test with synthesized two line ferrihydrite

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Seulki [Seoul Center, Korea Basic Science Institute, 6-7, Inchon-ro 22-gil, Seongbuk-gu, Seoul 02855 (Korea, Republic of); Yang, Kyung [Division of Public Infrastructure Assessment, Environmental Assessment Group, Korea Environmental Institute, Sejong 30147 (Korea, Republic of); Jho, Eun Hea [Department of Environmental Science, Hankuk University of Foreign Studies, 81 Oedae-ro, Mohyeonmyeon, Cheoin-gu, Yongin-si, Gyeonggi-do 17035 (Korea, Republic of); Nam, Kyoungphile, E-mail: kpnam@snu.ac.kr [Department of Civil and Environmental Engineering, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul 08826 (Korea, Republic of)

    2017-05-15

    Highlights: • Arsenic (As)-adsorbed and As-coprecipiated two-line ferrihydrites were synthesized. • Bioaccessibility was closely related to chemical binding type of As in Fe oxide. • Chemical binding type needs to be considered to characterize the risk of As in soil. - Abstract: Bioaccessible concentrations of As associated with Fe oxide as different chemical binding types were determined in soils using the in vitro Physiologically Based Extraction Test (PBET). When compared to the five-step sequential extraction data, most of the As extracted by in vitro PBET originated from the amorphous Fe oxide-bound fraction, and more importantly, the bioaccessibility of As ranged from 0 to 58.8% in 24 soil samples. Two batches of ferrihydrite were synthesized separately. For one batch, As was adsorbed onto the ferrihydrite after synthesis; for the other one, As was added while synthesizing ferrihydrite to co-precipitate. The bioaccessible concentration of As determined by in vitro PBET of the former was 415 mg of As/kg of ferrihydrite and that of the latter was 67 mg of As/kg of ferrihydrite. X-ray photoelectron spectra (XPS) analysis indicated that As–O–Fe bonds were evident in As-associated ferrihydrite sample and especially, As was found within the Fe oxide lattice in the co-precipitated sample. Our data suggest that binding type between As and Fe oxide should be considered when determining the bioaccessibility of As in soil, which, in turn, greatly influences the realistic risk of As present in soil.

  8. Reliability of self-reported use of amphetamine, barbiturates, benzodiazepines, cannabinoids, cocaine, methadone, and opiates among acutely hospitalized elderly medical patients

    DEFF Research Database (Denmark)

    Glintborg, B.; Olsen, L.; Poulsen, H.

    2008-01-01

    Undisclosed use of illicit drugs and prescription controlled substances is frequent in some settings. The aim of the present study was to estimate the reliability of self-reported use of amphetamine, barbiturates, benzodiazepines, cannabinoids, cocaine, methadone, and opiates among acutely...

  9. Reaction of diazepam and related benzodiazepines with chlorine. Kinetics, transformation products and in-silico toxicological assessment.

    Science.gov (United States)

    Carpinteiro, Inmaculada; Rodil, Rosario; Quintana, José Benito; Cela, Rafael

    2017-09-01

    In this work, the reaction of four benzodiazepines (diazepam, oxazepam, nordazepam and temazepam) during water chlorination was studied by means of liquid chromatography-quadrupole-time of flight-mass spectrometry (LC-QTOF-MS). For those compounds that showed a significant degradation, i.e. diazepam, oxazepam and nordazepam, parameters affecting to the reaction kinetics (pH, chlorine and bromide level) were studied in detail and transformation products were tentatively identified. The oxidation reactions followed pseudofirst-order kinetics with rate constants in the range of 1.8-42.5 M -1  s -1 , 0.13-1.16 M -1  s -1 and 0.04-20.4 M -1  s -1 corresponding to half-life values in the range of 1.9-146 min, 1.8-87 h and 2.5-637 h for oxazepam, nordazepam and diazepam, respectively, depending of the levels of studied parameters. Chlorine and pH affected significantly the reaction kinetics, where an increase of the pH resulted into a decrease of the reaction rate, whereas higher chlorine dosages led to faster kinetics, as expected in this case. The transformation of the studied benzodiazepines occurs mainly at the 1,4-diazepine 7-membered-ring, resulting in ring opening to form benzophenone derivatives or the formation of a 6-membered pyrimidine ring, leading to quinazoline derivatives. The formation of these by-products was also tested in real surface water samples observing kinetics of oxazepam degradation slower in river than in creek water, while the degradation of the two other benzodiazepines occurred only in the simpler sample (creek water). Finally, the acute and chronical toxicity and mutagenicity of precursors and transformation products were estimated using quantitative structure-activity relationship (QSAR) software tools: Ecological Structure Activity Relationships (ECOSAR) and Toxicity Estimation Software Tool (TEST), finding that some transformation products could be more toxic/mutagenic than the precursor drug, but additional test would be needed

  10. The Adenovirus Type 3 Dodecahedron's RGD Loop Comprises an HSPG Binding Site That Influences Integrin Binding

    Directory of Open Access Journals (Sweden)

    E. Gout

    2010-01-01

    Full Text Available Human type 3 adenovirus dodecahedron (a virus like particle made of twelve penton bases features the ability to enter cells through Heparan Sulphate Proteoglycans (HSPGs and integrins interaction and is used as a versatile vector to deliver DNA or proteins. Cryo-EM reconstruction of the pseudoviral particle with Heparan Sulphate (HS oligosaccharide shows an extradensity on the RGD loop. A set of mutants was designed to study the respective roles of the RGD sequence (RGE mutant and of a basic sequence located just downstream. Results showed that the RGE mutant binding to the HS deficient CHO-2241 cells was abolished and unexpectedly, mutation of the basic sequence (KQKR to AQAS dramatically decreased integrin recognition by the viral pseudoparticle. This basic sequence is thus involved in integrin docking, showing a close interplay between HSPGs and integrin receptors.

  11. Expedient Protocols for the Installation of Pyrimidine Based Privileged Templates on 2-Position of Pyrrolo[2,1-c][1,4]-benzodiazepine Nucleus Linked Through a p-phenoxyl Spacer

    Directory of Open Access Journals (Sweden)

    Anshu Agarwal

    2012-01-01

    Full Text Available Exceedingly facile single step expedient protocols based on the versatility and reactivity of corresponding intermediates : [2-(dimethylaminomethylene ketone] (5 and chalcone (6, derived from 2-(p-acetyl phenoxyl substituted analogue of pyrrolo[2,1-c][1,4]-benzodiazepine (4, have been developed to provide an easy installation of the pyrimidine based privileged templates at 2-position of pyrrolo[2,1-c][1,4]-benzodiazepine through a p-phenoxyl spacer, by utilizing the synthetic strategy depicted in schemes-1 and 2.

  12. The Tomato Nucleotide-binding Leucine-rich Repeat Immune Receptor I-2 Couples DNA-binding to Nucleotide-binding Domain Nucleotide Exchange*

    Science.gov (United States)

    Fenyk, Stepan; Dixon, Christopher H.; Gittens, William H.; Townsend, Philip D.; Sharples, Gary J.; Pålsson, Lars-Olof; Takken, Frank L. W.; Cann, Martin J.

    2016-01-01

    Plant nucleotide-binding leucine-rich repeat (NLR) proteins enable plants to recognize and respond to pathogen attack. Previously, we demonstrated that the Rx1 NLR of potato is able to bind and bend DNA in vitro. DNA binding in situ requires its genuine activation following pathogen perception. However, it is unknown whether other NLR proteins are also able to bind DNA. Nor is it known how DNA binding relates to the ATPase activity intrinsic to NLR switch function required to immune activation. Here we investigate these issues using a recombinant protein corresponding to the N-terminal coiled-coil and nucleotide-binding domain regions of the I-2 NLR of tomato. Wild type I-2 protein bound nucleic acids with a preference of ssDNA ≈ dsDNA > ssRNA, which is distinct from Rx1. I-2 induced bending and melting of DNA. Notably, ATP enhanced DNA binding relative to ADP in the wild type protein, the null P-loop mutant K207R, and the autoactive mutant S233F. DNA binding was found to activate the intrinsic ATPase activity of I-2. Because DNA binding by I-2 was decreased in the presence of ADP when compared with ATP, a cyclic mechanism emerges; activated ATP-associated I-2 binds to DNA, which enhances ATP hydrolysis, releasing ADP-bound I-2 from the DNA. Thus DNA binding is a general property of at least a subset of NLR proteins, and NLR activation is directly linked to its activity at DNA. PMID:26601946

  13. The Tomato Nucleotide-binding Leucine-rich Repeat Immune Receptor I-2 Couples DNA-binding to Nucleotide-binding Domain Nucleotide Exchange.

    Science.gov (United States)

    Fenyk, Stepan; Dixon, Christopher H; Gittens, William H; Townsend, Philip D; Sharples, Gary J; Pålsson, Lars-Olof; Takken, Frank L W; Cann, Martin J

    2016-01-15

    Plant nucleotide-binding leucine-rich repeat (NLR) proteins enable plants to recognize and respond to pathogen attack. Previously, we demonstrated that the Rx1 NLR of potato is able to bind and bend DNA in vitro. DNA binding in situ requires its genuine activation following pathogen perception. However, it is unknown whether other NLR proteins are also able to bind DNA. Nor is it known how DNA binding relates to the ATPase activity intrinsic to NLR switch function required to immune activation. Here we investigate these issues using a recombinant protein corresponding to the N-terminal coiled-coil and nucleotide-binding domain regions of the I-2 NLR of tomato. Wild type I-2 protein bound nucleic acids with a preference of ssDNA ≈ dsDNA > ssRNA, which is distinct from Rx1. I-2 induced bending and melting of DNA. Notably, ATP enhanced DNA binding relative to ADP in the wild type protein, the null P-loop mutant K207R, and the autoactive mutant S233F. DNA binding was found to activate the intrinsic ATPase activity of I-2. Because DNA binding by I-2 was decreased in the presence of ADP when compared with ATP, a cyclic mechanism emerges; activated ATP-associated I-2 binds to DNA, which enhances ATP hydrolysis, releasing ADP-bound I-2 from the DNA. Thus DNA binding is a general property of at least a subset of NLR proteins, and NLR activation is directly linked to its activity at DNA. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  14. Benzodiazepine use among employees of a private company Consumo de benzodiazepinas en trabajadores de una empresa privada Consumo de benzodiazepinas por trabalhadores de uma empresa privada

    Directory of Open Access Journals (Sweden)

    Alide Salazar Molina

    2008-08-01

    Full Text Available This study aimed to identify variables associated to the consumption of benzodiazepine among workers of a private company in the VIII Region, Chile. This is a cross-sectional and correlative study. Study population: 40 employees of a private company. The instruments included a questionnaire on socio-demographic variables and a benzodiazepine questionnaire. There was no record of benzodiazepine consumption at the moment of the study. Twenty percent (20% of the interviewees had already used benzodiazepine in the past, whereas, half of them (10% in the last year. The bivariate analysis of the last year consumption of benzodiazepine with work hours variables showed no significant relation (p=0.073. No association was found between benzodiazepine consumption and socio-demographic variables among the study participants.El propósito de este estudio fue identificar las variables asociadas al consumo de benzodiazepinas en población trabajadora de una institución privada de la VIII Región, Chile. Diseño cuantitativo, transversal y correlacional. Población del estudio: 40 trabajadores de una empresa privada de la VIII Región, Chile. Instrumentos recolectores de datos. Cuestionario de variables biosociodemográficas y Cuestionario de benzodiazepinas. No se registró consumo de benzodiazepinas al momento del estudio. 20% de los entrevistados tenía antecedentes de consumo de benzodiazepinas en el pasado, de ellos la mitad (10% en el último año. El análisis bivariado del consumo de benzodiazepinas en el último año con variables del trabajo sólo mostró una relación débilmente significativa (p= 0,073 con la jornada de trabajo. No se encontró asociación entre el consumo de benzodiazepines y las variables sociodemográficas entre los participantes del estudio.O propósito deste estudo foi avaliar as variáveis associadas ao consumo de benzodiazepínicos em população trabalhadora de uma instituição privada da VIII Região, Chile. Este é um

  15. Risk of hip fractures associated with benzodiazepines: Applying common protocol to a multi-database nested case-control study. The protect project

    NARCIS (Netherlands)

    Requena, Gema; Logie, John; González-González, Rocío; Gardarsdottir, Helga|info:eu-repo/dai/nl/321858131; Afonso, Ana; Souverein, Patrick C.|info:eu-repo/dai/nl/243074948; Merino, Elisa Martin; Boudiaf, Nada; Huerta, Consuelo; Bate, Andrew; Alvarez, Yolanda; García-Rodríguez, Luis A.; Reynolds, Robert; Schlienger, Raymond G.; De Groot, Mark C.H.|info:eu-repo/dai/nl/313936455; Klungel, Olaf H.|info:eu-repo/dai/nl/181447649; De Abajo, Francisco J.

    2014-01-01

    Background: The association between benzodiazepines (BZD) and hip fractures has been estimated in several observational studies although diverse methodologies and definitions have hampered comparability. Objectives: To evaluate the discrepancies in the risk estimates of hip/femur fractures

  16. dsRNA binding characterization of full length recombinant wild type and mutants Zaire ebolavirus VP35.

    Science.gov (United States)

    Zinzula, Luca; Esposito, Francesca; Pala, Daniela; Tramontano, Enzo

    2012-03-01

    The Ebola viruses (EBOVs) VP35 protein is a multifunctional major virulence factor involved in EBOVs replication and evasion of the host immune system. EBOV VP35 is an essential component of the viral RNA polymerase, it is a key participant of the nucleocapsid assembly and it inhibits the innate immune response by antagonizing RIG-I like receptors through its dsRNA binding function and, hence, by suppressing the host type I interferon (IFN) production. Insights into the VP35 dsRNA recognition have been recently revealed by structural and functional analysis performed on its C-terminus protein. We report the biochemical characterization of the Zaire ebolavirus (ZEBOV) full-length recombinant VP35 (rVP35)-dsRNA binding function. We established a novel in vitro magnetic dsRNA binding pull down assay, determined the rVP35 optimal dsRNA binding parameters, measured the rVP35 equilibrium dissociation constant for heterologous in vitro transcribed dsRNA of different length and short synthetic dsRNA of 8bp, and validated the assay for compound screening by assessing the inhibitory ability of auryntricarboxylic acid (IC(50) value of 50μg/mL). Furthermore, we compared the dsRNA binding properties of full length wt rVP35 with those of R305A, K309A and R312A rVP35 mutants, which were previously reported to be defective in dsRNA binding-mediated IFN inhibition, showing that the latter have measurably increased K(d) values for dsRNA binding and modified migration patterns in mobility shift assays with respect to wt rVP35. Overall, these results provide the first characterization of the full-length wt and mutants VP35-dsRNA binding functions. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. The GABA-A benzodiazepine receptor complex: Role of pet and spect in neurology and psychiatry; Der GABA-A-benzodiazepinrezeptorkomplex: Rolle von PET und SPECT in Neurologie und Psychiatrie

    Energy Technology Data Exchange (ETDEWEB)

    Juengling, F.D. [Abt. fuer Nuklearmedizin, Radiologie III, Universitaetsklinik Ulm (Germany); Schaefer, M.; Heinz, A. [Klinik fuer Psychiatrie und Psychotherapie, Charite, Humboldt-Univ. zu Berlin (Germany)

    2002-09-01

    Nuclear medicine imaging techniques such as positron emission tomography (PET) and single photon emission tomography (SPECT) for selective depiction of GABA-A-benzodiazepine receptor (GBZR) binding are complementary investigations in the diagnostic process of neurological and psychiatric disorders. This review summarizes the current knowledge about options and limitations of PET and SPECT for in vivo diagnostics in neurology and psychiatry. The growing importance of GBZR-imaging for the understanding of pathophysiology and pharmacological treatment in different psychiatric syndromes is discussed. (orig.) [German] Mit der Entwicklung selektiver Liganden fuer den GABA-A-Benzodiazepinrezeptorkomplex (GBZR) hat die nuklearmedizinische Bildgebung mittels positronen-emissionstomographie (PET) und single-photon-emissionscomputertomographie (SPECT) einen festen Stellenwert fuer Klinik und Forschung in der Neurologie und Psychiatrie erlangt. Die vorliegende Ueberblicksarbeit fasst den aktuellen Wissensstand von Anwendungsmoeglichkeiten und -grenzen der nuklearmedizinischen Bildgebung der GBZR in vivo zusammen und beleuchtet ihren klinischen Nutzen. Die wachsende Bedeutung fuer das Verstaendnis der Pathophysiologie und pharmakotherapeutischer Konzepte unterschiedlicher psychiatrischer Erkrankungen wird herausgestellt. (orig.)

  18. The elimination half-life of benzodiazepines and fall risk: two prospective observational studies.

    Science.gov (United States)

    de Vries, Oscar J; Peeters, Geeske; Elders, Petra; Sonnenberg, Caroline; Muller, Majon; Deeg, Dorly J H; Lips, Paul

    2013-11-01

    the STOPP criteria advise against the use of long-acting benzodiazepines (LBs). to study whether LBs are associated with a higher fall risk than short-acting benzodiazepines (SBs) (elimination half-life ≤ 10 h). we used base-line data and prospective fall follow-up from the Longitudinal Aging Study Amsterdam, a longitudinal cohort study including 1,509 community-dwelling older persons (Study 1) and from a separate fall prevention study with 564 older persons after a fall (Study 2). Time to the first fall after inclusion and number of falls in the first year after inclusion were the primary endpoints. both in Study 1 and Study 2 the use of SBs was associated with time to the first fall, hazard ratio (HR) 1.62 (95% CI: 1.03-2.56) and HR 1.64 (95% CI: 1.19-2.26),respectively. LBs were not significantly associated with time to first fall, HR 1.40 (0.85-2.31) and HR 1.08 (0.72-1.62). In both studies, the use of SBs was also associated with number of falls, odds ratio (OR) 1.28 (95% CI: 1.01-1.61) and OR 1.37 (95% CI: 1.10-1.70). LBs were not significantly associated with number of falls, OR 1.23 (0.96-1.57) and 1.10 (0.82-1.48). the use of SBs is not associated with a lower fall risk compared with LBs. The use of both SBs and LBs by old persons should be strongly discouraged.

  19. Learning and memory deficits in male adult mice treated with a benzodiazepine sleep-inducing drug during the juvenile period

    Directory of Open Access Journals (Sweden)

    Yusuke Furukawa

    2016-07-01

    Full Text Available Gamma-aminobutyric acid (GABA, the major inhibitory neurotransmitter in the mammalian central nervous system, is also known to be important for brain development. Therefore, disturbances of GABA receptor (GABA-R mediated signaling (GABA-R signal during brain development may influence normal brain maturation and cause late-onset brain malfunctions. In this study, we examined whether the temporal stimulation of the GABA-R signal during brain development induces late-onset adverse effects on the brain in adult male mice. To stimulate the GABA-R signal, we used either the benzodiazepine sleep-inducing drug triazolam (TZ or the non-benzodiazepine drug zolpidem (ZP. We detected deficits in learning and memory in mice treated with TZ during the juvenile period, as seen in the fear conditioning test. On the other hand, ZP administration during the juvenile period had little effect. In addition, decreased protein expression of GluR1 and GluR4, which are excitatory neurotransmitter receptors, was detected in the hippocampi of mice treated with TZ during the juvenile period. We measured mRNA expression of the immediate early genes (IEGs, which are neuronal activity markers, in the hippocampus shortly after the administration of TZ or ZP to juvenile mice. Decreased IEG expression was detected in mice with juvenile TZ administration, but not in mice with juvenile ZP administration. Our findings demonstrate that TZ administration during the juvenile period can induce irreversible brain dysfunction in adult mice. It may need to take an extra care for the prescription of benzodiazepine sleep-inducing drugs to juveniles because it might cause late onset learning and memory defects.

  20. Insulin binding to individual rat skeletal muscles

    International Nuclear Information System (INIS)

    Koerker, D.J.; Sweet, I.R.; Baskin, D.G.

    1990-01-01

    Studies of insulin binding to skeletal muscle, performed using sarcolemmal membrane preparations or whole muscle incubations of mixed muscle or typical red (soleus, psoas) or white [extensor digitorum longus (EDL), gastrocnemius] muscle, have suggested that red muscle binds more insulin than white muscle. We have evaluated this hypothesis using cryostat sections of unfixed tissue to measure insulin binding in a broad range of skeletal muscles; many were of similar fiber-type profiles. Insulin binding per square millimeter of skeletal muscle slice was measured by autoradiography and computer-assisted densitometry. We found a 4.5-fold range in specific insulin tracer binding, with heart and predominantly slow-twitch oxidative muscles (SO) at the high end and the predominantly fast-twitch glycolytic (FG) muscles at the low end of the range. This pattern reflects insulin sensitivity. Evaluation of displacement curves for insulin binding yielded linear Scatchard plots. The dissociation constants varied over a ninefold range (0.26-2.06 nM). Binding capacity varied from 12.2 to 82.7 fmol/mm2. Neither binding parameter was correlated with fiber type or insulin sensitivity; e.g., among three muscles of similar fiber-type profile, the EDL had high numbers of low-affinity binding sites, whereas the quadriceps had low numbers of high-affinity sites. In summary, considerable heterogeneity in insulin binding was found among hindlimb muscles of the rat, which can be attributed to heterogeneity in binding affinities and the numbers of binding sites. It can be concluded that a given fiber type is not uniquely associated with a set of insulin binding parameters that result in high or low binding

  1. Premedication with benzodiazepines for upper gastrointestinal endoscopy: Comparison between oral midazolam and sublingual alprazolam

    Directory of Open Access Journals (Sweden)

    Vahid Sebghatollahi

    2017-01-01

    Full Text Available Background: Premedication with orally administered benzodiazepines is effective in reducing anxiety and discomfort related to endoscopic procedures. We evaluated the efficacy and safety of oral midazolam in comparison to sublingual alprazolam as premedication for esophagogastroduodenoscopy (EGD. Materials and Methods: Adult candidates for diagnostic EGD received either oral midazolam (7.5 mg in 15 cc apple juice or sublingual alprazolam (0.5 mg 30 min before EGD. Procedural anxiety and pain/discomfort were assessed using 11-point numerical rating scales. Patients' overall tolerance (using a four-point Likert scale and willingness to repeat the EGD, if necessary, were also assessed. Blood pressure, heart rate, and arterial oxygen saturation were monitored from medication to 30 min after the procedure. Results: Patients experienced a similar reduction in procedural anxiety after medication with oral midazolam and sublingual alprazolam; mean (standard deviation [SD] of 1.86 [1.63] and 2.02 [1.99] points, respectively, P = 0.91. Compared to oral midazolam, pain/discomfort scores were lower with sublingual alprazolam; mean (SD of 4.80 (3.01 versus 3.68 (3.28, P = 0.024. There was no significant difference between the two groups in patients' tolerance, willingness to repeat the procedure, or hemodynamic events. Conclusion: Oral midazolam and sublingual alprazolam are equally effective in reducing EGD-related anxiety; however, EGD-related pain/discomfort is lower with alprazolam. Both benzodiazepines are equally safe and can be used as premedication for patients undergoing diagnostic EGD.

  2. Systemic or Intra-Amygdala Injection of a Benzodiazepine (Midazolam) Impairs Extinction but Spares Re-Extinction of Conditioned Fear Responses

    Science.gov (United States)

    Hart, Genevra; Harris, Justin A.; Westbrook, R. Frederick

    2009-01-01

    Rats were subjected to one or two cycles of fear conditioning and extinction, injected with a benzodiazepine, midazolam, before the first or second extinction, and tested for long-term inhibition of fear responses (freezing). In Experiment 1, inhibition of context-conditioned fear was spared when midazolam was injected before the second…

  3. GABA(A)-benzodiazepine receptor complex sensitivity in 5-HT(1A) receptor knockout mice on a 129/Sv background.

    NARCIS (Netherlands)

    Pattij, T.; Groenink, L.; Oosting, R.S.; Gugten, J. van der; Maes, R.A.A.; Olivier, B.

    2002-01-01

    Previous studies in 5-HT(1A) receptor knockout (1AKO) mice on a mixed Swiss Websterx129/Sv (SWx129/Sv) and a pure 129/Sv genetic background suggest a differential gamma-aminobutyric acid (GABA(A))-benzodiazepine receptor complex sensitivity in both strains, independent from the anxious phenotype. To

  4. Mood stabilizer treatment increases serotonin type 1A receptor binding in bipolar depression

    Science.gov (United States)

    Nugent, Allison C; Carlson, Paul J; Bain, Earle E; Eckelman, William; Herscovitch, Peter; Manji, Husseini; Zarate, Carlos A; Drevets, Wayne C

    2013-01-01

    Abnormal serotonin type 1A (5-HT1A) receptor function and binding have been implicated in the pathophysiology of mood disorders. Preclinical studies have consistently shown that stress decreases the gene expression of 5-HT1A receptors in experimental animals, and that the associated increase in hormone secretion plays a crucial role in mediating this effect. Chronic administration of the mood stabilizers lithium and divalproex (valproate semisodium) reduces glucocorticoid signaling and function in the hippocampus. Lithium has further been shown to enhance 5-HT1A receptor function. To assess whether these effects translate to human subject with bipolar disorder (BD), positron emission tomography (PET) and [18F]trans-4-fluoro-N-(2-[4-(2-methoxyphenyl) piperazino]-ethyl)-N-(2-pyridyl) cyclohexanecarboxamide ([18F]FCWAY) were used to acquire PET images of 5-HT1A receptor binding in 10 subjects with BD, before and after treatment with lithium or divalproex. Mean 5-HT1A binding potential (BPP) significantly increased following mood stabilizer treatment, most prominently in the mesiotemporal cortex (hippocampus plus amygdala). When mood state was also controlled for, treatment was associated with increases in BPP in widespread cortical areas. These preliminary findings are consistent with the hypothesis that these mood stabilizers enhance 5-HT1A receptor expression in BD, which may underscore an important component of these agents' mechanism of action. PMID:23926239

  5. The Breast Cancer-Associated Glycoforms of MUC1, MUC1-Tn and sialyl-Tn, Are Expressed in COSMC Wild-Type Cells and Bind the C-Type Lectin MGL.

    Directory of Open Access Journals (Sweden)

    Richard Beatson

    Full Text Available Aberrant glycosylation occurs in the majority of human cancers and changes in mucin-type O-glycosylation are key events that play a role in the induction of invasion and metastases. These changes generate novel cancer-specific glyco-antigens that can interact with cells of the immune system through carbohydrate binding lectins. Two glyco-epitopes that are found expressed by many carcinomas are Tn (GalNAc-Ser/Thr and STn (NeuAcα2,6GalNAc-Ser/Thr. These glycans can be carried on many mucin-type glycoproteins including MUC1. We show that the majority of breast cancers carry Tn within the same cell and in close proximity to extended glycan T (Galβ1,3GalNAc the addition of Gal to the GalNAc being catalysed by the T synthase. The presence of active T synthase suggests that loss of the private chaperone for T synthase, COSMC, does not explain the expression of Tn and STn in breast cancer cells. We show that MUC1 carrying both Tn or STn can bind to the C-type lectin MGL and using atomic force microscopy show that they bind to MGL with a similar dead adhesion force. Tumour associated STn is associated with poor prognosis and resistance to chemotherapy in breast carcinomas, inhibition of DC maturation, DC apoptosis and inhibition of NK activity. As engagement of MGL in the absence of TLR triggering may lead to anergy, the binding of MUC1-STn to MGL may be in part responsible for some of the characteristics of STn expressing tumours.

  6. Structural analogs of human insulin-like growth factor I with reduced affinity for serum binding proteins and the type 2 insulin-like growth factor receptor

    International Nuclear Information System (INIS)

    Bayne, M.L.; Applebaum, J.; Chicchi, G.G.; Hayes, N.S.; Green, B.G.; Cascieri, M.A.

    1988-01-01

    Four structural analogs of human insulin-like growth factor I (hIGF-I) have been prepared by site-directed mutagenesis of a synthetic IGF-I gene and subsequent expression and purification of the mutant protein from the conditioned media of transformed yeast. [Phe -1 , Val 1 , Asn 2 , Gln 3 , His 4 , Ser 8 , His 9 , Glu 12 , Tyr 15 , Leu 16 ]IGF-I (B-chain mutant), in which the first 16 amino acids of hIGF-I were replaced with the first 17 amino acids of the B-chain of insulin, has >1000-, 100-, and 2-fold reduced potency for human serum binding proteins, the rat liver type 2 IGF receptor, and the human placental type 1 IGF receptor, respectively. The B-chain mutant also has 4-fold increased affinity for the human placental insulin receptor. [Gln 3 , Ala 4 ] IGF-I has 4-fold reduced affinity for human serum binding proteins, but is equipotent to hIGF-I at the types 1 and 2 IGF and insulin receptors. [Tyr 15 , Leu 16 ] IGH-I has 4-fold reduced affinity for human serum binding proteins and 10-fold increased affinity for the insulin receptor. The peptide in which these four-point mutations are combined, [Gln 3 , Ala 4 , Tyr 15 ,Leu 16 ]IGF-I, has 600-fold reduced affinity for the serum binding proteins. All four of these mutants stimulate DNA synthesis in the rat vascular smooth muscle cell line A10 with potencies reflecting their potency at the type 1 IGF receptor. These studies identify some of the domains of hIGF-I which are responsible for maintaining high affinity binding with the serum binding protein and the type 2 IGF receptor. In addition, These peptides will be useful in defining the role of the type 2 IGF receptor and serum binding proteins in the physiological actions of hIGF-I

  7. IGF2 mRNA-binding protein 2: biological function and putative role in type 2 diabetes

    DEFF Research Database (Denmark)

    Christiansen, J.; Kolte, A.M.; Hansen, T.O.

    2009-01-01

    Recent genome-wide association (GWA) studies of type 2 diabetes (T2D) have implicated IGF2 mRNA-binding protein 2 (IMP2/IGF2BP2) as one of the several factors in the etiology of late onset diabetes. IMP2 belongs to a family of oncofetal mRNA-binding proteins implicated in RNA localization...... and T2D Udgivelsesdato: 2009/11......, stability, and translation that are essential for normal embryonic growth and development. This review provides a background to the IMP protein family with an emphasis on human IMP2, followed by a closer look at the GWA studies to evaluate the significance, if any, of the proposed correlation between IMP2...

  8. Synthesis of iodine-123 labelled analogues of the partial agonist (S)-and (R)-bretazenil for the study of CNS benzodiazepine receptors using SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Katsifis, Andrew; Mattner, Filomena; McPhee, Meredith; Kassiou, Michael; Najdovski, Ljubco; Dikic, Branko [Australian Nuclear Science and Technology Organisation, Radiopharmaceutical Div., Menai, Sydney, NSW (Australia)

    1996-09-01

    The (S) and (R)-[{sup 123}I]iodinated analogues of the benzodiazepine receptor partial agonist bretazenil have been synthesized for study of the central benzodiazepine receptor using SPECT, (S)- and (R)-[{sup 123}I]iodobretazenil were prepared from the appropriate tin precursors by electrophilic iododestannylation with Na[{sup 123}I] in the presence of Chloramine-T. The products were purified by semi-preparative reverse-phase HPLC with radiochemical yields of 80% in a total synthesis time of 50 minutes. The specific activity was determined to be greater than 2500 Ci/mmol. The radiochemical and chemical purity assessed by radio-TLC and HPLC were found to be 98%. The enantiomeric purity of the (S) and (R) isomers were greater than 97% as assessed by analytical chiral HPLC analysis. (author).

  9. Glycosaminoglycans mediate retention of the poxvirus type I interferon binding protein at the cell surface to locally block interferon antiviral responses

    Science.gov (United States)

    Montanuy, Imma; Alejo, Ali; Alcami, Antonio

    2011-01-01

    Eradication of smallpox was accomplished 30 yr ago, but poxviral infections still represent a public health concern due to the potential release of variola virus or the emergence of zoonotic poxviruses, such as monkeypox virus. A critical determinant of poxvirus virulence is the inhibition of interferons (IFNs) by the virus-encoded type I IFN-binding protein (IFNα/βBP). This immunomodulatory protein is secreted and has the unique property of interacting with the cell surface in order to prevent IFN-mediated antiviral responses. However, the mechanism of its attachment to the cell surface remains unknown. Using surface plasmon resonance and cell-binding assays, we report that the IFNα/βBP from vaccinia virus, the smallpox vaccine, interacts with cell surface glycosaminoglycans (GAGs). Analysis of the contribution of different regions of the protein to cell surface binding demonstrated that clusters of basic residues in the first immunoglobulin domain mediate GAG interactions. Furthermore, mutation of the GAG-interaction motifs does not affect its IFN-binding and -blocking capacity. Functional conservation of GAG-binding sites is demonstrated for the IFNα/βBP from variola and monkeypox viruses, extending our understanding of immune modulation by the most virulent human poxviruses. These results are relevant for the design of improved vaccines and intervention strategies.—Montanuy, I., Alejo, A., Alcami, A. Glycosaminoglycans mediate retention of the poxvirus type I interferon binding protein at the cell surface to locally block interferon antiviral responses. PMID:21372110

  10. "Diazepam loading": ¿Can a strategy for preventing alcohol withdrawal be used to treat benzodiazepine use disorder?

    Science.gov (United States)

    Oliveras, Clara; Fortea, Adriana; Espinosa, Laura; Barrio, Pablo; Lligoña, Anna; Balcells-Olivero, Mercè

    2018-04-15

    Benzodiazepines (BZDs) are central nervous system (CNS) depressants which are widely used to treat insomnia and anxiety, despite having long-term adverse side effects. (Fortea González, Oriolo, Balcells Oliveró, Sánchez Del Valle & Castellvi, 2017). As with alcohol, continued use can lead to tolerance and dependence phenomena. Discontinuation in such cases can produce abstinence symptoms such as tremors, anxiety, seizures and, occasionally, death (Brett y Murnion, 2015).

  11. Sugar-Binding Profiles of Chitin-Binding Lectins from the Hevein Family: A Comprehensive Study

    Directory of Open Access Journals (Sweden)

    Yoko Itakura

    2017-05-01

    Full Text Available Chitin-binding lectins form the hevein family in plants, which are defined by the presence of single or multiple structurally conserved GlcNAc (N-acetylglucosamine-binding domains. Although they have been used as probes for chito-oligosaccharides, their detailed specificities remain to be investigated. In this study, we analyzed six chitin-binding lectins, DSA, LEL, PWM, STL, UDA, and WGA, by quantitative frontal affinity chromatography. Some novel features were evident: WGA showed almost comparable affinity for pyridylaminated chitotriose and chitotetraose, while LEL and UDA showed much weaker affinity, and DSA, PWM, and STL had no substantial affinity for the former. WGA showed selective affinity for hybrid-type N-glycans harboring a bisecting GlcNAc residue. UDA showed extensive binding to high-mannose type N-glycans, with affinity increasing with the number of Man residues. DSA showed the highest affinity for highly branched N-glycans consisting of type II LacNAc (N-acetyllactosamine. Further, multivalent features of these lectins were investigated by using glycoconjugate and lectin microarrays. The lectins showed substantial binding to immobilized LacNAc as well as chito-oligosaccharides, although the extents to which they bound varied among them. WGA showed strong binding to heavily sialylated glycoproteins. The above observations will help interpret lectin-glycoprotein interactions in histochemical studies and glyco-biomarker investigations.

  12. Sugar-binding sites of the HA1 subcomponent of Clostridium botulinum type C progenitor toxin.

    Science.gov (United States)

    Nakamura, Toshio; Tonozuka, Takashi; Ide, Azusa; Yuzawa, Takayuki; Oguma, Keiji; Nishikawa, Atsushi

    2008-02-22

    Clostridium botulinum type C 16S progenitor toxin contains a hemagglutinin (HA) subcomponent, designated HA1, which appears to play an important role in the effective internalization of the toxin in gastrointestinal epithelial cells and in creating a broad specificity for the oligosaccharide structure that corresponds to various targets. In this study, using the recombinant protein fused to glutathione S-transferase, we investigated the binding specificity of the HA1 subcomponent to sugars and estimated the binding sites of HA1 based on X-ray crystallography and soaking experiments using various sugars. N-Acetylneuraminic acid, N-acetylgalactosamine, and galactose effectively inhibited the binding that occurs between glutathione S-transferase-HA1 and mucins, whereas N-acetylglucosamine and glucose did not inhibit it. The crystal structures of HA1 complex with N-acetylneuraminic acid, N-acetylgalactosamine, and galactose were also determined. There are two sugar-binding sites, sites I and II. Site I corresponds to the electron densities noted for all sugars and is located at the C-terminal beta-trefoil domain, while site II corresponds to the electron densities noted only for galactose. An aromatic amino acid residue, Trp176, at site I has a stacking interaction with the hexose ring of the sugars. On the other hand, there is no aromatic residue at site II; thus, the interaction with galactose seems to be poor. The double mutant W176A at site I and D271F at site II has no avidity for N-acetylneuraminic acid but has avidity for galactose. In this report, the binding specificity of botulinum C16S toxin HA1 to various sugars is demonstrated based on its structural features.

  13. Five of Five VHHs Neutralizing Poliovirus Bind the Receptor-Binding Site.

    Science.gov (United States)

    Strauss, Mike; Schotte, Lise; Thys, Bert; Filman, David J; Hogle, James M

    2016-01-13

    Nanobodies, or VHHs, that recognize poliovirus type 1 have previously been selected and characterized as candidates for antiviral agents or reagents for standardization of vaccine quality control. In this study, we present high-resolution cryo-electron microscopy reconstructions of poliovirus with five neutralizing VHHs. All VHHs bind the capsid in the canyon at sites that extensively overlap the poliovirus receptor-binding site. In contrast, the interaction involves a unique (and surprisingly extensive) surface for each of the five VHHs. Five regions of the capsid were found to participate in binding with all five VHHs. Four of these five regions are known to alter during the expansion of the capsid associated with viral entry. Interestingly, binding of one of the VHHs, PVSS21E, resulted in significant changes of the capsid structure and thus seems to trap the virus in an early stage of expansion. We describe the cryo-electron microscopy structures of complexes of five neutralizing VHHs with the Mahoney strain of type 1 poliovirus at resolutions ranging from 3.8 to 6.3Å. All five VHHs bind deep in the virus canyon at similar sites that overlap extensively with the binding site for the receptor (CD155). The binding surfaces on the VHHs are surprisingly extensive, but despite the use of similar binding surfaces on the virus, the binding surface on the VHHs is unique for each VHH. In four of the five complexes, the virus remains essentially unchanged, but for the fifth there are significant changes reminiscent of but smaller in magnitude than the changes associated with cell entry, suggesting that this VHH traps the virus in a previously undescribed early intermediate state. The neutralizing mechanisms of the VHHs and their potential use as quality control agents for the end game of poliovirus eradication are discussed. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  14. Mid-aged and aged wild-type and progestin receptor knockout (PRKO) mice demonstrate rapid progesterone and 3alpha,5alpha-THP-facilitated lordosis.

    Science.gov (United States)

    Frye, C A; Sumida, K; Lydon, J P; O'Malley, B W; Pfaff, D W

    2006-05-01

    Progesterone (P) and its 5alpha-reduced metabolite, 3alpha-hydroxy-5alpha-pregnan-20-one (3alpha,5alpha-THP), facilitate sexual behavior of rodents via agonist-like actions at intracellular progestin receptors (PRs) and membrane GABA(A)/benzodiazepine receptor complexes (GBRs), respectively. Given that ovarian secretion of progestins declines with aging, whether or not senescent mice are responsive to progestins was of interest. Homozygous PR knockout (PRKO) or wild-type mice that were between 10-12 (mid-aged) or 20-24 (aged) months of age were administered P or 3alpha,5alpha-THP, and the effect on lordosis were examined. Effects of a progestin-priming regimen that enhances PR-mediated (experiment 1) or more rapid, PR-independent effects of progestins (experiments 2 and 3) on sexual behavior were examined. Levels of P, 3alpha,5alpha-THP, and muscimol binding were examined in tissues from aged mice (experiment 4). Wild-type, but not PRKO, mice were responsive when primed with 17beta-estradiol (E(2); 0.5 microg) and administered P (500 microg, subcutaneously). Mid-aged wild-type mice demonstrated greater increases in lordosis 6 h later compared to their pre-P, baseline test than did aged wild-type mice (experiment 1). Lordosis of younger and older wild-type, but not PRKO, mice was significantly increased within 5 min of intravenous (IV) administration of P (100 ng), compared with E(2)-priming alone (experiment 2). However, wild-type and PRKO mice demonstrated significant increases in lordosis 5 min after IV administration of 3alpha,5alpha-THP, an effect which was more pronounced in mid-aged than in aged animals (100 ng-experiment 3). In tissues from aged wild-type and PRKO mice, levels of P, 3alpha,5alpha-THP, and muscimol binding were increased by P administration (experiment 4). PR binding was lower in the cortex of PRKO than that of wild-type mice. Mid-aged and aged PRKO and wild-type mice demonstrated rapid P or 3alpha,5alpha-THP-facilitated lordosis that may be

  15. Adverse Events Associated with Flumazenil Treatment for the Management of Suspected Benzodiazepine Intoxication--A Systematic Review with Meta-Analyses of Randomised Trials

    DEFF Research Database (Denmark)

    Penninga, Elisabeth I; Graudal, Niels; Ladekarl, Morten Baekbo

    2016-01-01

    Flumazenil is used for the reversal of benzodiazepine overdose. Serious adverse events (SAEs) including seizures and cardiac arrhythmias have been reported in patients treated with flumazenil, and the clinical advantage of flumazenil treatment has been questioned. The objective was to assess...

  16. Mannose-Binding Lectin Binds to Amyloid Protein and Modulates Inflammation

    Directory of Open Access Journals (Sweden)

    Mykol Larvie

    2012-01-01

    Full Text Available Mannose-binding lectin (MBL, a soluble factor of the innate immune system, is a pattern recognition molecule with a number of known ligands, including viruses, bacteria, and molecules from abnormal self tissues. In addition to its role in immunity, MBL also functions in the maintenance of tissue homeostasis. We present evidence here that MBL binds to amyloid β peptides. MBL binding to other known carbohydrate ligands is calcium-dependent and has been attributed to the carbohydrate-recognition domain, a common feature of other C-type lectins. In contrast, we find that the features of MBL binding to Aβ are more similar to the reported binding characteristics of the cysteine-rich domain of the unrelated mannose receptor and therefore may involve the MBL cysteine-rich domain. Differences in MBL ligand binding may contribute to modulation of inflammatory response and may correlate with the function of MBL in processes such as coagulation and tissue homeostasis.

  17. Patterns of binding of aluminum-containing adjuvants to Haemophilus influenzae type b and meningococcal group C conjugate vaccines and components

    Science.gov (United States)

    Otto, Robert B.D.; Burkin, Karena; Amir, Saba Erum; Crane, Dennis T.; Bolgiano, Barbara

    2015-01-01

    The basis of Haemophilus influenzae type b (Hib) and Neisseria meningitidis serogroup C (MenC) glycoconjugates binding to aluminum-containing adjuvants was studied. By measuring the amount of polysaccharide and protein in the non-adsorbed supernatant, the adjuvant, aluminum phosphate, AlPO4, was found to be less efficient than aluminum hydroxide, Al(OH)3 at binding to the conjugates, at concentrations relevant to licensed vaccine formulations and when equimolar. At neutral pH, binding of TT conjugates to AlPO4 was facilitated through the carrier protein, with only weak binding of AlPO4 to CRM197 being observed. There was slightly higher binding of either adjuvant to tetanus toxoid conjugates, than to CRM197 conjugates. This was verified in AlPO4 formulations containing DTwP–Hib, where the adsorption of TT-conjugated Hib was higher than CRM197-conjugated Hib. At neutral pH, the anionic Hib and MenC polysaccharides did not appreciably bind to AlPO4, but did bind to Al(OH)3, due to electrostatic interactions. Phosphate ions reduced the binding of the conjugates to the adjuvants. These patterns of adjuvant adsorption can form the basis for future formulation studies with individual and combination vaccines containing saccharide-protein conjugates. PMID:26194164

  18. Pharmacology of morphine and morphine-3-glucuronide at opioid, excitatory amino acid, GABA and glycine binding sites

    Energy Technology Data Exchange (ETDEWEB)

    Bartlett, S.E.; Smith, M.T. (Department of Pharmacy, The University of Queensland (Australia)); Dood, P.R. (Clinical Research Centre, Royal Brisbane Hospital Foundation, Brisbane (Australia))

    1994-07-01

    Morphine in high doses and its major metabolite, morphine-3-glucuronide, cause CNS excitation following intrathecal and intracerebroventricular administration by an unknown mechanism. This study investigated whether morphine and morphine-3-glucuronide interact at major excitatory (glutamate), major inhibitory (GABA or glycine), or opioid binding sites. Homogenate binding assays were performed using specific radioligands. At opioid receptors, morphine-3-glucuronide and morphine caused an equipotent sodium shift, consistent with morphine-3-glucuronide behaving as an agonist. This suggests that morphine-3-glucuronide-mediated excitation is not caused by an interaction at opioid receptors. Morphine-3-glucuronide and morphine caused a weak inhibition of the binding of [sup 3]H-MK801 (non-competitive antagonist) and [sup 125]I-ifenprodil (polyamine site antagonist), but at unphysiologically high concentrations. This suggests that CNS excitation would not result from an interaction of morphine-3-glucuronide and high-dose morphine with these sites on the NMDA receptor. Morphine-3-glucuronide and morphine inhibited the binding of [sup 3]H-muscimol (GABA receptor agonist), [sup 3]H-diazepam and [sup 3]H-flunitraxepam (benzodiazepine agonists) binding very weakly, suggesting the excitatory effects of morphine-3-glucuronide and high-dose morphine are not elicited through GABA[sub A] receptors. Morphine-3-glucuronide and high-dose morphine did not prevent re-uptake of glutamate into presynaptic nerve terminals. In addition, morphine-3-glucuronide and morphine did not inhibit the binding of [sup 3]H-strychnine (glycine receptor antagonist) to synaptic membranes prepared from bovine spinal cord. It is concluded that excitation caused by high-dose morphine and morphine-3-glucuronide is not mediated by an interaction with postsynaptic amino acid receptors. (au) (30 refs.).

  19. Synthesis and evaluation of radioiodinated ligands for the study of peripheral benzodiazepine receptors using SPECT

    International Nuclear Information System (INIS)

    Katsifis, A.; Mattner, F.; Mardon, K.; Dikic, B.; Papazian, V.; Greguric, I.

    2002-01-01

    Full text: The peripheral benzodiazepine receptor (PBR) is a multimeric protein complex located in the outer mitochondrial membrane and predominantly found in steroid producing organs and glial cells in the brain. The PBR have been implicated in the control of cell proliferation and differentiation and shown to display increased levels in a variety of malignant tumours and neurodegenerative disorders. A series of potent imidazo[1,2-a]pyridines have been prepared for development as radiopharmaceuticals to study these disorders in patients using nuclear medicine imaging techniques. In vitro studies indicate that compounds substituted with an electronegative atom in the 6 position of the pyridine ring, a lipophilic group or halogen in the 4'-position of the 2-phenyl ring, and lower alkyl methyl or ethyl substituents on the amide nitrogens of the side chain, exhibit high affinity and selective binding. ' N'N'-dimethyl- and the N'N'-diethyl 6-chloro-(4'-iodophenyl)imidazo[1,2-a]pyridine-3-acetamide 1 and 2 displayed optimum in vitro properties and were thus selected for radiolabelling with the diagnostic radionuclide iodine-123. Radioiodination was achieved by iododestannylation of the corresponding tributyl stannane precursor in the presence of peracetic acid. Purification by C-18 reverse phase HPLC gave the desired products in 70-80% radiochemical yields and in greater than 98% radiochemical purity. Biodistribution studies in normal rodents indicated high uptake of radioactivity in tissues with known PBR sites. Preliminary imaging studies in rodents bearing mammary adenocarcinomas indicated high uptake in the tumour with retention of activity after 24 h. The synthesis, structure activity studies, radiolabelling and biological studies of these compounds will be presented

  20. Radiosynthesis and initial evaluation of [18F]-FEPPA for PET imaging of peripheral benzodiazepine receptors

    International Nuclear Information System (INIS)

    Wilson, Alan A.; Garcia, Armando; Parkes, Jun; McCormick, Patrick; Stephenson, Karin A.; Houle, Sylvain; Vasdev, Neil

    2008-01-01

    Introduction: A novel [ 18 F]-radiolabelled phenoxyanilide, [ 18 F]-FEPPA, has been synthesized and evaluated, in vitro and ex vivo, as a potential positron emission tomography imaging agent for the peripheral benzodiazepine receptor (PBR). Methods: [ 18 F]-FEPPA and two other radiotracers for imaging PBR, namely [ 11 C]-PBR28 and [ 11 C]-PBR28-d3, were synthesised and evaluated in vitro and ex vivo as potential PBR imaging agents. Results: [ 18 F]-FEPPA is efficiently prepared in one step from its tosylate precursor and [ 18 F]-fluoride in high radiochemical yields and at high specific activity. FEPPA displayed a K i of 0.07 nM for PBR in rat mitochondrial membrane preparations and a suitable lipophilicity for brain penetration (log P of 2.99 at pH 7.4). Upon intravenous injection into rats, [ 18 F]-FEPPA showed moderate brain uptake [standard uptake value (SUV) of 0.6 at 5 min] and a slow washout (SUV of 0.35 after 60 min). Highest uptake of radioactivity was seen in the hypothalamus and olfactory bulb, regions previously reported to be enriched in PBR in rat brain. Analysis of plasma and brain extracts demonstrated that [ 18 F]-FEPPA was rapidly metabolized, but no lipophilic metabolites were observed in either preparation and only 5% radioactive metabolites were present in brain tissue extracts. Blocking studies to determine the extent of specific binding of [ 18 F]-FEPPA in rat brain were problematic due to large perturbations in circulating radiotracer and the lack of a reference region. Conclusions: Further evaluation of the potential of [ 18 F]-FEPPA will require the employment of rigorous kinetic models and/or appropriate animal models

  1. Identification of binding domains in the herpes simplex virus type 1 small capsid protein pUL35 (VP26).

    Science.gov (United States)

    Apcarian, Arin; Cunningham, Anthony L; Diefenbach, Russell J

    2010-11-01

    In this study, fragments of the small capsid protein pUL35 (VP26) from herpes simplex virus type 1 (HSV-1) were generated to identify binding domains for a number of known ligands. Analysis of the binding of dynein light chain subunits, DYNLT1 and DYNLT3, as well the HSV-1 structural proteins pUL19 (VP5) and pUL37 was then undertaken using the LexA yeast two-hybrid assay. The N-terminal half of pUL35, in particular residues 30-43, was identified as a common region for the binding of DYNLT1 and DYNLT3. Additional distinct regions in the C terminus of pUL35 also contribute to the binding of DYNLT1 and DYNLT3. In contrast, only the C-terminal half of pUL35 was found to mediate the binding of pUL19 and pUL37 through distinct regions. The relevance of this information to the role of pUL35 in viral transport and assembly is discussed.

  2. SECRET domain of variola virus CrmB protein can be a member of poxviral type II chemokine-binding proteins family.

    Science.gov (United States)

    Antonets, Denis V; Nepomnyashchikh, Tatyana S; Shchelkunov, Sergei N

    2010-10-27

    Variola virus (VARV) the causative agent of smallpox, eradicated in 1980, have wide spectrum of immunomodulatory proteins to evade host immunity. Recently additional biological activity was discovered for VARV CrmB protein, known to bind and inhibit tumour necrosis factor (TNF) through its N-terminal domain homologous to cellular TNF receptors. Besides binding TNF, this protein was also shown to bind with high affinity several chemokines which recruit B- and T-lymphocytes and dendritic cells to sites of viral entry and replication. Ability to bind chemokines was shown to be associated with unique C-terminal domain of CrmB protein. This domain named SECRET (Smallpox virus-Encoded Chemokine Receptor) is unrelated to the host proteins and lacks significant homology with other known viral chemokine-binding proteins or any other known protein. De novo modelling of VARV-CrmB SECRET domain spatial structure revealed its apparent structural homology with cowpox virus CC-chemokine binding protein (vCCI) and vaccinia virus A41 protein, despite low sequence identity between these three proteins. Potential ligand-binding surface of modelled VARV-CrmB SECRET domain was also predicted to bear prominent electronegative charge which is characteristic to known orthopoxviral chemokine-binding proteins. Our results suggest that SECRET should be included into the family of poxviral type II chemokine-binding proteins and that it might have been evolved from the vCCI-like predecessor protein.

  3. Mutations in type 3 reovirus that determine binding to sialic acid are contained in the fibrous tail domain of viral attachment protein sigma1.

    Science.gov (United States)

    Chappell, J D; Gunn, V L; Wetzel, J D; Baer, G S; Dermody, T S

    1997-03-01

    The reovirus attachment protein, sigma1, determines numerous aspects of reovirus-induced disease, including viral virulence, pathways of spread, and tropism for certain types of cells in the central nervous system. The sigma1 protein projects from the virion surface and consists of two distinct morphologic domains, a virion-distal globular domain known as the head and an elongated fibrous domain, termed the tail, which is anchored into the virion capsid. To better understand structure-function relationships of sigma1 protein, we conducted experiments to identify sequences in sigma1 important for viral binding to sialic acid, a component of the receptor for type 3 reovirus. Three serotype 3 reovirus strains incapable of binding sialylated receptors were adapted to growth in murine erythroleukemia (MEL) cells, in which sialic acid is essential for reovirus infectivity. MEL-adapted (MA) mutant viruses isolated by serial passage in MEL cells acquired the capacity to bind sialic acid-containing receptors and demonstrated a dependence on sialic acid for infection of MEL cells. Analysis of reassortant viruses isolated from crosses of an MA mutant virus and a reovirus strain that does not bind sialic acid indicated that the sigma1 protein is solely responsible for efficient growth of MA mutant viruses in MEL cells. The deduced sigma1 amino acid sequences of the MA mutant viruses revealed that each strain contains a substitution within a short region of sequence in the sigma1 tail predicted to form beta-sheet. These studies identify specific sequences that determine the capacity of reovirus to bind sialylated receptors and suggest a location for a sialic acid-binding domain. Furthermore, the results support a model in which type 3 sigma1 protein contains discrete receptor binding domains, one in the head and another in the tail that binds sialic acid.

  4. Contextos e padrões do uso indevido de benzodiazepínicos entre mulheres Contexts and patterns of undue use benzodiazepine among women

    Directory of Open Access Journals (Sweden)

    Ana Rosa Lins de Souza

    2013-04-01

    Full Text Available O uso indevido de benzodiazepínicos, especialmente entre mulheres, tem despertado preocupação na área de saúde pública. Este estudo objetivou compreender qualitativamente crenças e valores associados ao consumo indevido dessa substância por mulheres. Foram entrevistadas trinta e três mulheres (18-60 anos com histórico de uso indevido de benzodiazepínicos no último ano, selecionadas intencionalmente e por critérios. Os discursos foram transcritos e submetidos à análise de conteúdo com auxílio do software NVivo. A maioria das entrevistadas referiu tempo de uso bem superior ao recomendado (mediana: 7 anos e compra com receita médica. Os motivos de uso mais citados foram diminuição da ansiedade, problemas de insônia e fuga dos problemas. Apesar de reconhecerem a possibilidade de dependência, esta não motivou a interrupção do uso. O acompanhamento médico não pareceu, necessariamente, estimular a percepção de risco dos benzodiazepínicos, sendo um fator que favoreceu a manutenção do uso prolongado.The undue use of benzodiazepines particularly among women has raised concern in the public health area. This qualitative study aimed at understanding the beliefs and values associated with undue use of benzodiazepines among women. Thirty-three participants (aged between 18 and 60 with a history of undue use of benzodiazepines in the past year were selected intentionally using specific criteria. The interviews were fully transcribed and subjected to content analysis using NVivo software. The majority of respondents reported use for longer than the recommended duration (median 7 years and they purchased the drug with a medical prescription. Reasons for use most given were to deal with anxiety, to improve sleep and to "flee from problems." Even those who acknowledged the possibility of being addicted were not motivated to stop taking the drug. Medical supervision did not necessarily seem to influence the perception of risk of

  5. Benzodiazepine receptor equilibrium constants for flumazenil and midazolam determined in humans with the single photon emission computer tomography tracer [123I]iomazenil

    DEFF Research Database (Denmark)

    Videbaek, C; Friberg, L; Holm, S

    1993-01-01

    twice, once without receptor blockade and once with a constant degree of partial blockade of the benzodiazepine receptors by infusion of nonradioactive flumazenil (Lanexat) or midazolam (Dormicum). Single photon emission computer tomography and blood sampling were performed intermittently for 6 h after...

  6. Midazolam inhibits hippocampal long-term potentiation and learning through dual central and peripheral benzodiazepine receptor activation and neurosteroidogenesis.

    Science.gov (United States)

    Tokuda, Kazuhiro; O'Dell, Kazuko A; Izumi, Yukitoshi; Zorumski, Charles F

    2010-12-15

    Benzodiazepines (BDZs) enhance GABA(A) receptor inhibition by direct actions on central BDZ receptors (CBRs). Although some BDZs also bind mitochondrial receptors [translocator protein (18 kDa) (TSPO)] and promote the synthesis of GABA-enhancing neurosteroids, the role of neurosteroids in the clinical effects of BDZs is unknown. In rat hippocampal slices, we compared midazolam, an anesthetic BDZ, with clonazepam, an anticonvulsant/anxiolytic BDZ that activates CBRs selectively. Midazolam, but not clonazepam, increased neurosteroid levels in CA1 pyramidal neurons without changing TSPO immunostaining. Midazolam, but not clonazepam, also augmented a form of spike inhibition after stimulation adjacent to the pyramidal cell layer and inhibited induction of long-term potentiation. These effects were prevented by finasteride, an inhibitor of neurosteroid synthesis, or 17PA [17-phenyl-(3α,5α)-androst-16-en-3-ol], a blocker of neurosteroid effects on GABA(A) receptors. Moreover, the synaptic effects were mimicked by a combination of clonazepam with FGIN (2-[2-(4-fluorophenyl)-1H-indol-3-yl]-N,N-dihexylacetamide), a selective TSPO agonist, or a combination of clonazepam with exogenous allopregnanolone. Consistent with these in vitro results, finasteride abolished the effects of midazolam on contextual fear learning when administrated 1 d before midazolam injection. Thus, dual activation of CBRs and TSPO appears to result in unique actions of clinically important BDZs. Furthermore, endogenous neurosteroids are shown to be important regulators of pyramidal neuron function and synaptic plasticity.

  7. Apo calmodulin binding to the L-type voltage-gated calcium channel Cav1.2 IQ peptide

    International Nuclear Information System (INIS)

    Lian Luyun; Myatt, Daniel; Kitmitto, Ashraf

    2007-01-01

    The influx of calcium through the L-type voltage-gated calcium channels (LTCCs) is the trigger for the process of calcium-induced calcium release (CICR) from the sarcoplasmic recticulum, an essential step for cardiac contraction. There are two feedback mechanisms that regulate LTCC activity: calcium-dependent inactivation (CDI) and calcium-dependent facilitation (CDF), both of which are mediated by calmodulin (CaM) binding. The IQ domain (aa 1645-1668) housed within the cytoplasmic domain of the LTCC Ca v 1.2 subunit has been shown to bind both calcium-loaded (Ca 2+ CaM ) and calcium-free CaM (apoCaM). Here, we provide new data for the structural basis for the interaction of apoCaM with the IQ peptide using NMR, revealing that the apoCaM C-lobe residues are most significantly perturbed upon complex formation. In addition, we have employed transmission electron microscopy of purified LTCC complexes which shows that both apoCaM and Ca 2+ CaM can bind to the intact channel

  8. Zinc finger arrays binding human papillomavirus types 16 and 18 genomic DNA: precursors of gene-therapeutics for in-situ reversal of associated cervical neoplasia

    Directory of Open Access Journals (Sweden)

    Wayengera Misaki

    2012-07-01

    Full Text Available Abstract Background Human papillomavirus (HPV types 16 and 18 are the high-risk, sexually transmitted infectious causes of most cervical intraepithelial neoplasias (CIN or cancers. While efficacious vaccines to reduce the sexual acquisition of these high-risk HPVs have recently been introduced, no virus-targeted therapies exist for those already exposed and infected. Considering the oncogenic role of the transforming (E6 and E7 genes of high-risk HPVs in the slow pathogenesis of cervical cancer, we hypothesize that timely disruption or abolition of HPV genome expression within pre-cancerous lesions identified at screening may reverse neoplasia. We aimed to derive model zinc finger nucleases (ZFNs for mutagenesis of the genomes of two high-risk HPV (types 16 & 18. Methods and results Using ZiFiT software and the complete genomes of HPV types16 and 18, we computationally generated the consensus amino acid sequences of the DNA-binding domains (F1, F2, & F3 of (i 296 & 327 contextually unpaired (or single three zinc-finger arrays (sZFAs and (ii 9 & 13 contextually paired (left and right three- zinc-finger arrays (pZFAs that bind genomic DNA of HPV-types 16 and 18 respectively, inclusive of the E7 gene (s/pZFAHpV/E7. In the absence of contextually paired three-zinc-finger arrays (pZFAs that bind DNA corresponding to the genomic context of the E6 gene of either HPV type, we derived the DNA binding domains of another set of 9 & 14 contextually unpaired E6 gene-binding ZFAs (sZFAE6 to aid the future quest for paired ZFAs to target E6 gene sequences in both HPV types studied (pZFAE6. This paper presents models for (i synthesis of hybrid ZFNs that cleave within the genomic DNA of either HPV type, by linking the gene sequences of the DNA-cleavage domain of the FokI endonuclease FN to the gene sequences of a member of the paired-HPV-binding ZFAs (pZFAHpV/E7 + FN, and (ii delivery of the same into precancerous lesions using HPV-derived viral plasmids or

  9. The effect of ethanol on 35-S-TBPS binding to mouse brain membranes in the presence of chloride

    International Nuclear Information System (INIS)

    Liljequist, S.; Culp, S.; Tabakoff, B.

    1989-01-01

    The effect of in vitro and in vivo administration of ethanol on the binding of 35 S-t-butyl-bicyclophosphorothionate ( 35 S-TBPS) to cortical brain membranes of C57B1 mice was investigated using KCl (100 mM) containing assay media. The in vitro addition of ethanol produced a dose-dependent inhibition of basal 35 S-TBPS binding. In the presence of chloride ions, GABA and pentobarbital had a biphasic action (stimulation followed by inhibition) on 35 S-TBPS binding, whereas diazepam only stimulated the binding. Ethanol reduced the stimulatory effects of GABA and pentobarbital in a dose-dependent manner, but had no effect on the enhancement of 35 S-TBPS binding produced by diazepam. 35 S-TBPS binding to cortical brain membranes was inhibited by the putative Cl - channel blocking agent DIDS. This inhibitory action of DIDS was significantly, and dose-dependently reduced by ethanol (≤ 100 mM ethanol). Chronic ethanol ingestion in vivo, which produced tolerance to and physical dependence on ethanol in the animals, did not alter the stimulatory and inhibitory effects of GABA and pentobarbital on 35 S-TBPS binding. The enhancement of 35 S-TBPS binding produced by diazepam was slightly, but significantly, enhanced in brain membranes from animals which had undergone 24 hours of ethanol withdrawal. Chronic ethanol treatment did not change the potency of picrotoxin and of the peripheral BDZ-receptor ligand RO 5-4864 to competitively inhibit 35 S-TBPS binding. Our results suggest that in vitro addition of ethanol alters the activity of the activity of the GABA benzodiazepine (BDZ) receptor complex. Although there was no change in basal 35 S-TBPS binding following chronic in vivo ethanol administration, our curent data suggest that chronic ethanol ingestion may cause specific changes of the GABA BDZ receptor proteins, in this study revealed as an altered modulation of 35 S-TBPS binding by diazepam. (author)

  10. Water binding of proteins in the processing frankfurter-type sausages. Part. 1. Water-binding ability of freeze-dried meat fractions containing myofibrillar and stromal proteins.

    Science.gov (United States)

    Heinevetter, L; Gassmann, B; Kroll, J

    1987-01-01

    As soon as possible and 48 h after slaughter respectively, from both blade-bone muscle groups of cattle and pig carcasses the "thick pieces" were excised, extracted, and fractionated. Residues and precipitates from water and salt extracts resulted were freeze-dried, and an improved Baumann capillary suction apparatus was used to measure their water binding capacity (WBC) with and without addition of 2% sodium chloride and/or heating to 80 degrees C. With one exception the WBC results followed a relative pattern demonstrating the final residues (stromal proteins and leavings of myofibrillar proteins) binding the highest amount of added water, precipitates of dialysis (mainly containing myofibrillar proteins) a remarkable amount and powdered meats the least. As scanning electron micrographs confirmed, there were no fibrous structures in the precipitates resulted from dialysis of salt solutions (1.0 mol/1). Heating decreased the spontaneous water uptake of all fractions. Addition of sodium chloride had only a noticeable capillary-suction and swelling effect on unheated samples. Hence swelling of undissolved protein structures (extraction of myosin and possibly of actomyosin) is therefore not the only way for water binding in frankfurter-type sausages.

  11. Heart-type fatty-acid-binding protein (FABP3 is a lysophosphatidic acid-binding protein in human coronary artery endothelial cells

    Directory of Open Access Journals (Sweden)

    Ryoko Tsukahara

    2014-01-01

    Full Text Available Fatty-acid-binding protein 3, muscle and heart (FABP3, also known as heart-type FABP, is a member of the family of intracellular lipid-binding proteins. It is a small cytoplasmic protein with a molecular mass of about 15 kDa. FABPs are known to be carrier proteins for transporting fatty acids and other lipophilic substances from the cytoplasm to the nucleus, where these lipids are released to a group of nuclear receptors such as peroxisome proliferator-activated receptors (PPARs. In this study, using lysophosphatidic acid (LPA-coated agarose beads, we have identified FABP3 as an LPA carrier protein in human coronary artery endothelial cells (HCAECs. Administration of LPA to HCAECs resulted in a dose-dependent increase in PPARγ activation. Furthermore, the LPA-induced PPARγ activation was abolished when the FABP3 expression was reduced using small interfering RNA (siRNA. We further show that the nuclear fraction of control HCAECs contained a significant amount of exogenously added LPA, whereas FABP3 siRNA-transfected HCAECs had a decreased level of LPA in the nucleus. Taken together, these results suggest that FABP3 governs the transcriptional activities of LPA by targeting them to cognate PPARγ in the nucleus.

  12. Estimation of the Binding Free Energy of AC1NX476 to HIV-1 Protease Wild Type and Mutations Using Free Energy Perturbation Method.

    Science.gov (United States)

    Ngo, Son Tung; Mai, Binh Khanh; Hiep, Dinh Minh; Li, Mai Suan

    2015-10-01

    The binding mechanism of AC1NX476 to HIV-1 protease wild type and mutations was studied by the docking and molecular dynamics simulations. The binding free energy was calculated using the double-annihilation binding free energy method. It is shown that the binding affinity of AC1NX476 to wild type is higher than not only ritonavir but also darunavir, making AC1NX476 become attractive candidate for HIV treatment. Our theoretical results are in excellent agreement with the experimental data as the correlation coefficient between calculated and experimentally measured binding free energies R = 0.993. Residues Asp25-A, Asp29-A, Asp30-A, Ile47-A, Gly48-A, and Val50-A from chain A, and Asp25-B from chain B play a crucial role in the ligand binding. The mutations were found to reduce the receptor-ligand interaction by widening the binding cavity, and the binding propensity is mainly driven by the van der Waals interaction. Our finding may be useful for designing potential drugs to combat with HIV. © 2015 John Wiley & Sons A/S.

  13. Null alleles and sequence variations at primer binding sites of STR loci within multiplex typing systems.

    Science.gov (United States)

    Yao, Yining; Yang, Qinrui; Shao, Chengchen; Liu, Baonian; Zhou, Yuxiang; Xu, Hongmei; Zhou, Yueqin; Tang, Qiqun; Xie, Jianhui

    2018-01-01

    Rare variants are widely observed in human genome and sequence variations at primer binding sites might impair the process of PCR amplification resulting in dropouts of alleles, named as null alleles. In this study, 5 cases from routine paternity testing using PowerPlex ® 21 System for STR genotyping were considered to harbor null alleles at TH01, FGA, D5S818, D8S1179, and D16S539, respectively. The dropout of alleles was confirmed by using alternative commercial kits AGCU Expressmarker 22 PCR amplification kit and AmpFℓSTR ® . Identifiler ® Plus Kit, and sequencing results revealed a single base variation at the primer binding site of each STR locus. Results from the collection of previous reports show that null alleles at D5S818 were frequently observed in population detected by two PowerPlex ® typing systems and null alleles at D19S433 were mostly observed in Japanese population detected by two AmpFℓSTR™ typing systems. Furthermore, the most popular mutation type appeared the transition from C to T with G to A, which might have a potential relationship with DNA methylation. Altogether, these results can provide helpful information in forensic practice to the elimination of genotyping discrepancy and the development of primer sets. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Characterization of Small Molecule Scaffolds that Bind to the Shigella Type III Secretion System Protein IpaD

    Science.gov (United States)

    Dey, Supratim; Anbanandam, Asokan; Mumford, Ben E.; De Guzman, Roberto N.

    2017-01-01

    Many pathogens such as Shigella and other bacteria assemble the type III secretion system (T3SS) nanoinjector to inject virulence proteins into their target cells to cause infectious diseases in humans. The rise of drug resistance among pathogens that rely on the T3SS for infectivity, plus the dearth of new antibiotics require alternative strategies in developing new antibiotics. The Shigella T3SS tip protein IpaD is an attractive target for developing anti-infectives because of its essential role in virulence and its exposure on the bacterial surface. Currently, the only known small molecules that bind to IpaD are bile salts sterols. Here, we identified four new small molecule scaffolds that bind to IpaD based on the methylquinoline, pyrrolidin-aniline, hydroxyindole, and morpholinoaniline scaffolds. NMR mapping revealed potential hotspots in IpaD for binding small molecules. These scaffolds can be used as building blocks in developing small molecule inhibitors of IpaD that could lead to new anti-infectives. PMID:28750143

  15. An analytic study of central benzodiazepine receptor in the surgically resected tissues of patients with intractable localization-related epilepsy. Quantitative analysis using 125I-iomazenil autoradiography

    International Nuclear Information System (INIS)

    Doi, Toshiaki; Matsuda, Kazumi; Mihara, Tadahiro; Yagi, Kazuichi; Seino, Masakazu

    1998-01-01

    The authors report a quantitative autoradiographic analysis of benzodiazepine receptors using the partial inverse agonist 125 I-iomazenil in surgically resected tissues of 27 patients with intractable partial epilepsies. Pathological diagnosis of these tissues was; 14 mesial temporal sclerosis (MTS), 8 dysembryoplastic neuroepithelial tumor (DNT), 4 cortical dysplasia (CD) and 1 angioma. In MTS patients, the density of benzodiazepine receptors decreased in CA1, CA3 and CA4. The layers of gyrus dentatus were displaced with a thick and high density band. These findings were similar to simultaneous GABA-A stain findings. The decrease of receptor in each hippocampal structure highly correlated to the degree of cell loss in CA1, CA3 and CA4. The receptors were almost absent in the main lesions of DNT and angioma, and showed irregular distributions in the cortex around these lesions. The receptor densities of CD were parallel to Palmini's pathological grading. Nine cases were analyzed using 123 I-iomazenil SPECT before surgery after obtaining informed consent. Eight of them revealed marked low accumulations in the areas corresponding to the epileptogenic foci. We conclude that our results support histochemically the clinical availability of 123 I-iomazenil SPECT as a non-invasive technique for detecting the changes in benzodiazepine receptor densities in patients with partial epilepsies. (author)

  16. Exploiting the acylating nature of the imide-Ugi intermediate: a straightforward synthesis of tetrahydro-1,4-benzodiazepin-2-ones.

    Science.gov (United States)

    Mossetti, Riccardo; Saggiorato, Dèsirèe; Tron, Gian Cesare

    2011-12-16

    We describe a simple and novel protocol for the synthesis of tetrahydro-1,4-benzodiazepin-2-ones with three points of diversity, exploiting the acylating properties of the recently rediscovered Ugi-imide. The final compounds can be easily prepared in three synthetic steps using a multicomponent reaction, a Staudinger reduction, and an acylative protocol, with good to excellent yields for each synthetic step.

  17. Discovery of an imidazopyridine-containing 1,4-benzodiazepine nonpeptide vitronectin receptor (alpha v beta 3) antagonist with efficacy in a restenosis model.

    Science.gov (United States)

    Keenan, R M; Lago, M A; Miller, W H; Ali, F E; Cousins, R D; Hall, L B; Hwang, S M; Jakas, D R; Kwon, C; Louden, C; Nguyen, T T; Ohlstein, E H; Rieman, D J; Ross, S T; Samanen, J M; Smith, B R; Stadel, J; Takata, D T; Vickery, L; Yuan, C C; Yue, T L

    1998-11-17

    In the 3-oxo-1,4-benzodiazepine-2-acetic acid series of vitronectin receptor (alpha v beta 3) antagonists, a compound containing an imidazopyridine arginine mimetic was discovered which had sufficient potency and i.v. pharmacokinetics for demonstration of efficacy in a rat restenosis model.

  18. Patterns of binding of aluminum-containing adjuvants to Haemophilus influenzae type b and meningococcal group C conjugate vaccines and components.

    Science.gov (United States)

    Otto, Robert B D; Burkin, Karena; Amir, Saba Erum; Crane, Dennis T; Bolgiano, Barbara

    2015-09-01

    The basis of Haemophilus influenzae type b (Hib) and Neisseria meningitidis serogroup C (MenC) glycoconjugates binding to aluminum-containing adjuvants was studied. By measuring the amount of polysaccharide and protein in the non-adsorbed supernatant, the adjuvant, aluminum phosphate, AlPO4, was found to be less efficient than aluminum hydroxide, Al(OH)3 at binding to the conjugates, at concentrations relevant to licensed vaccine formulations and when equimolar. At neutral pH, binding of TT conjugates to AlPO4 was facilitated through the carrier protein, with only weak binding of AlPO4 to CRM197 being observed. There was slightly higher binding of either adjuvant to tetanus toxoid conjugates, than to CRM197 conjugates. This was verified in AlPO4 formulations containing DTwP-Hib, where the adsorption of TT-conjugated Hib was higher than CRM197-conjugated Hib. At neutral pH, the anionic Hib and MenC polysaccharides did not appreciably bind to AlPO4, but did bind to Al(OH)3, due to electrostatic interactions. Phosphate ions reduced the binding of the conjugates to the adjuvants. These patterns of adjuvant adsorption can form the basis for future formulation studies with individual and combination vaccines containing saccharide-protein conjugates. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  19. SECRET domain of variola virus CrmB protein can be a member of poxviral type II chemokine-binding proteins family

    Directory of Open Access Journals (Sweden)

    Shchelkunov Sergei N

    2010-10-01

    Full Text Available Abstract Background Variola virus (VARV the causative agent of smallpox, eradicated in 1980, have wide spectrum of immunomodulatory proteins to evade host immunity. Recently additional biological activity was discovered for VARV CrmB protein, known to bind and inhibit tumour necrosis factor (TNF through its N-terminal domain homologous to cellular TNF receptors. Besides binding TNF, this protein was also shown to bind with high affinity several chemokines which recruit B- and T-lymphocytes and dendritic cells to sites of viral entry and replication. Ability to bind chemokines was shown to be associated with unique C-terminal domain of CrmB protein. This domain named SECRET (Smallpox virus-Encoded Chemokine Receptor is unrelated to the host proteins and lacks significant homology with other known viral chemokine-binding proteins or any other known protein. Findings De novo modelling of VARV-CrmB SECRET domain spatial structure revealed its apparent structural homology with cowpox virus CC-chemokine binding protein (vCCI and vaccinia virus A41 protein, despite low sequence identity between these three proteins. Potential ligand-binding surface of modelled VARV-CrmB SECRET domain was also predicted to bear prominent electronegative charge which is characteristic to known orthopoxviral chemokine-binding proteins. Conclusions Our results suggest that SECRET should be included into the family of poxviral type II chemokine-binding proteins and that it might have been evolved from the vCCI-like predecessor protein.

  20. Anxiety Distorders: Types, Diagnosis and Treatment | NIH MedlinePlus the Magazine

    Science.gov (United States)

    ... medications used for anxiety disorders are antidepressants, anti-anxiety drugs, and beta-blockers. Be aware that some medications are effective only ... anxiety disorders. Benzodiazepines (anti-anxiety medications) The anti-anxiety medications called benzodiazepines ... control some of the physical symptoms ...

  1. Crystal Structure of the Receptor-Binding Domain of Botulinum Neurotoxin Type HA, Also Known as Type FA or H.

    Science.gov (United States)

    Yao, Guorui; Lam, Kwok-Ho; Perry, Kay; Weisemann, Jasmin; Rummel, Andreas; Jin, Rongsheng

    2017-03-08

    Botulinum neurotoxins (BoNTs), which have been exploited as cosmetics and muscle-disorder treatment medicines for decades, are well known for their extreme neurotoxicity to humans. They pose a potential bioterrorism threat because they cause botulism, a flaccid muscular paralysis-associated disease that requires immediate antitoxin treatment and intensive care over a long period of time. In addition to the existing seven established BoNT serotypes (BoNT/A-G), a new mosaic toxin type termed BoNT/HA (aka type FA or H) was reported recently. Sequence analyses indicate that the receptor-binding domain (H C ) of BoNT/HA is ~84% identical to that of BoNT/A1. However, BoNT/HA responds differently to some potent BoNT/A-neutralizing antibodies (e.g., CR2) that target the H C . Therefore, it raises a serious concern as to whether BoNT/HA poses a new threat to our biosecurity. In this study, we report the first high-resolution crystal structure of BoNT/HA-H C at 1.8 Å. Sequence and structure analyses reveal that BoNT/HA and BoNT/A1 are different regarding their binding to cell-surface receptors including both polysialoganglioside (PSG) and synaptic vesicle glycoprotein 2 (SV2). Furthermore, the new structure also provides explanations for the ~540-fold decreased affinity of antibody CR2 towards BoNT/HA compared to BoNT/A1. Taken together, these new findings advance our understanding of the structure and function of this newly identified toxin at the molecular level, and pave the way for the future development of more effective countermeasures.

  2. Crystal Structure of the Receptor-Binding Domain of Botulinum Neurotoxin Type HA, Also Known as Type FA or H

    Directory of Open Access Journals (Sweden)

    Guorui Yao

    2017-03-01

    Full Text Available Botulinum neurotoxins (BoNTs, which have been exploited as cosmetics and muscle-disorder treatment medicines for decades, are well known for their extreme neurotoxicity to humans. They pose a potential bioterrorism threat because they cause botulism, a flaccid muscular paralysis-associated disease that requires immediate antitoxin treatment and intensive care over a long period of time. In addition to the existing seven established BoNT serotypes (BoNT/A–G, a new mosaic toxin type termed BoNT/HA (aka type FA or H was reported recently. Sequence analyses indicate that the receptor-binding domain (HC of BoNT/HA is ~84% identical to that of BoNT/A1. However, BoNT/HA responds differently to some potent BoNT/A-neutralizing antibodies (e.g., CR2 that target the HC. Therefore, it raises a serious concern as to whether BoNT/HA poses a new threat to our biosecurity. In this study, we report the first high-resolution crystal structure of BoNT/HA-HC at 1.8 Å. Sequence and structure analyses reveal that BoNT/HA and BoNT/A1 are different regarding their binding to cell-surface receptors including both polysialoganglioside (PSG and synaptic vesicle glycoprotein 2 (SV2. Furthermore, the new structure also provides explanations for the ~540-fold decreased affinity of antibody CR2 towards BoNT/HA compared to BoNT/A1. Taken together, these new findings advance our understanding of the structure and function of this newly identified toxin at the molecular level, and pave the way for the future development of more effective countermeasures.

  3. Crystal Structure of the Receptor-Binding Domain of Botulinum Neurotoxin Type HA, Also Known as Type FA or H

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Guorui; Lam, Kwok-ho; Perry, Kay; Weisemann, Jasmin; Rummel, Andreas; Jin, Rongsheng (Cornell); (Dusseldorf); (UCI)

    2017-03-01

    Botulinum neurotoxins (BoNTs), which have been exploited as cosmetics and muscle-disorder treatment medicines for decades, are well known for their extreme neurotoxicity to humans. They pose a potential bioterrorism threat because they cause botulism, a flaccid muscular paralysis-associated disease that requires immediate antitoxin treatment and intensive care over a long period of time. In addition to the existing seven established BoNT serotypes (BoNT/A–G), a new mosaic toxin type termed BoNT/HA (aka type FA or H) was reported recently. Sequence analyses indicate that the receptor-binding domain (HC) of BoNT/HA is ~84% identical to that of BoNT/A1. However, BoNT/HA responds differently to some potent BoNT/A-neutralizing antibodies (e.g., CR2) that target the HC. Therefore, it raises a serious concern as to whether BoNT/HA poses a new threat to our biosecurity. In this study, we report the first high-resolution crystal structure of BoNT/HA-HC at 1.8 Å. Sequence and structure analyses reveal that BoNT/HA and BoNT/A1 are different regarding their binding to cell-surface receptors including both polysialoganglioside (PSG) and synaptic vesicle glycoprotein 2 (SV2). Furthermore, the new structure also provides explanations for the ~540-fold decreased affinity of antibody CR2 towards BoNT/HA compared to BoNT/A1. Taken together, these new findings advance our understanding of the structure and function of this newly identified toxin at the molecular level, and pave the way for the future development of more effective countermeasures

  4. Histamine type I (H1) receptor radioligand binding studies on normal T cell subsets, B cells, and monocytes

    International Nuclear Information System (INIS)

    Cameron, W.; Doyle, K.; Rocklin, R.E.

    1986-01-01

    A single, specific binding site for [ 3 H]pyrilamine on normal human T helper, T suppressor, B cells, and monocytes was documented. The binding of the radioligand to its receptor is reversible with cold H 1 antagonist, saturates at 40 to 60 nM, and binding equilibrium is achieved in 2 to 4 min. Using a computer program (Ligand), the authors calculated the dissociation constants, binding capacities, and numbers of receptors per cell for each of the different cell types. Monocytes were found to have the highest affinity for [ 3 H]pyrilamine, followed by T helper cells, B cells and T suppressor cells (K/sub D/ = 44.6 +/- 49.4 nM). T suppressor cells were found to express the higher number of H 1 receptors per cell followed by B cells, T helper cells, and monocytes. The binding affinity for [ 3 H]pyrilamine increased over a 48-hr period, whereas the number of receptors per T cell was essentially unchanged. In contrast, T cells stimulated with Con A or PHA were shown to have a greater than fourfold increase in the number of receptors per cell, whereas the binding affinity for [ 3 H]pyrilamine decreased over the 48-hr period. Although the function of H 1 receptors on T cells, B cells, and monocytes has not been completely defined, this receptor has the potential of playing an important role in the modulating the immune response

  5. Comparison of the Effects of Haloperidol and Benzodiazepines Used for Postictal Psychiatric Symptoms on Seizure Recurrence: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Pınar Hanife Kara

    2017-09-01

    Full Text Available Aim: Patients with epilepsy may experience a number of psychiatric and cognitive symptoms or behavioral manifestations during the period of a seizure and the postictal period. The aim of this pilot study was to compare the effects medications commonly used in emergency departments for postictal psychiatric symptoms on seizure recurrence. Methods: Data of 32 epileptic patients, who presented to İzmir Katip Çelebi University Atatürk Research and Training Hospital Emergency Department with postictal psychiatric symptoms between January 2013 and December 2014, were retrospectively collected. Demographic and clinical data were obtained from the emergency department charts and neurology and psychiatry consultation records. Data regarding administered drugs were obtained from the hospital data processing system. The chi-square test, Mann-Whitney U test and the Kruskal-Wallis test were used as statistical methods. Bonferroni correction was performed for post-hoc analysis. Results: There were no differences in the seizure recurrence rate between benzodiazepine, haloperidol and without medication groups (p>0.05. Conclusion: Our results suggest that benzodiazepines and haloperidol do not affect the development of recurrent seizures when administered for postictal symptoms.

  6. The effect of ethanol on sup 35 -S-TBPS binding to mouse brain membranes in the presence of chloride

    Energy Technology Data Exchange (ETDEWEB)

    Liljequist, S.; Culp, S.; Tabakoff, B. (Laboratory for Studies of Neuroadaptive Processes, National Institute on Alcohol Abuse and Alcoholism, NIH, Bethesda (USA))

    1989-01-01

    The effect of in vitro and in vivo administration of ethanol on the binding of {sup 35}S-t-butyl-bicyclophosphorothionate ({sup 35}S-TBPS) to cortical brain membranes of C57B1 mice was investigated using KCl containing assay media. The in vitro addition of ethanol produced a dose-dependent inhibition of basal {sup 35}S-TBPS binding. In the presence of chloride ions, GABA and pentobarbital had a biphasic action on {sup 35}S-TBPS binding, whereas diazepam only stimulated the binding. Ethanol reduced the stimulatory effects of GABA and pentobarbital in a dose-dependent manner, but had no effect on the enhancement of {sup 35}S-TBPS binding produced by diazepam. {sup 35}S-TBPS binding to cortical brain membranes was inhibited by the putative Cl{sup -} channel blocking agent DIDS. This inhibitory action of DIDS was significantly, and dose-dependently reduced by ethanol. Chronic ethanol ingestion in vivo, which produced tolerance to and physical dependence on ethanol in the animals, did not alter the stimulatory and inhibitory effects of GABA and pentobarbital on {sup 35}S-TBPS binding. The enhancement of {sup 35}S-TBPS binding produced by diazepam was slightly, but significantly, enhanced in brain membranes from animals which had undergone 24 hours of ethanol withdrawal. Chronic ethanol treatment did not change the potency of picrotoxin and of the peripheral BDZ-receptor ligand RO 5-4864 to competitively inhibit {sup 35}S-TBPS binding. Our results suggest that in vitro addition of ethanol alters the activity of the activity of the GABA benzodiazepine (BDZ) receptor complex. Although there was no change in basal {sup 35}S-TBPS binding following chronic in vivo ethanol administration, our curent data suggest that chronic ethanol ingestion may cause specific changes of the GABA BDZ receptor proteins, in this study revealed as an altered modulation of {sup 35}S-TBPS binding by diazepam.

  7. Regional increases in [11C]flumazenil binding after epilepsy surgery

    International Nuclear Information System (INIS)

    Savic, I.; Blomqvist, G.; Halldin, C.; Litton, J.E.; Gulyas, B.

    1998-01-01

    Introduction - Animal experiments suggest that epileptic seizures alter the expression of mRNA for neuro-receptors. PET measurements with [ 11 C]flumazenil show that patients with partial seizures have a reduced density of benzodiazepine (BZ) receptors in the epileptogenic regions (ER) and some of the target areas for seizure activity, the so called projection areas. Recent data suggest that the degree of BZ receptor reduction in ER is correlated to seizure frequency. We therefore hypothesized that seizure activity can alter the BZ receptor binding, and that some of these changes could normalize when the seizures disappeared. Methods - In 4 patients whose seizures were generated by mesial temporal lobe structures, BZ receptor density was measured with [ 11 C]flumazenil PET before, and 1 year after the epilepsy surgery and cessation of seizures. By use of a computerized anatomical brain atlas the same regions were analyzed in both PET scans, and the results related to data from 7 healthy controls. Results - Presurgical PET scans showed reductions in BZ receptor density in the epileptogenic regions and some of its primary projection areas. Other cortical regions had normal values. Postsurgically, the calculated BZ receptor density normalized (29±17% increase) in several of the affected projection areas, whereas the values in other cortical regions remained unaltered. Conclusion - Regional reductions in BZ receptor density may be dynamic and related to seizures. The present preliminary observations encourage further studies on seizure-related changes in regional receptor binding in humans. (au)

  8. Surface-bound capsular polysaccharide of type Ia group B Streptococcus mediates C1 binding and activation of the classic complement pathway

    International Nuclear Information System (INIS)

    Levy, N.J.; Kasper, D.L.

    1986-01-01

    The role of surface-bound type Ia group B Streptococcus (GBS) capsular polysaccharide in anti-body-independent binding of C1 and activation of the classic component pathway was investigated. In a radiolabeled bacterial-polymorphonuclear leukocyte (PMN) association assay, a measure of bacterial opsonization, preincubation of 3 H-type Ia GBS with purified F(ab') 2 to the organism blocked the association of the bacteria with PMN', and the inhibitory effect was dose dependent. The specificity of F(ab') 2 blocking was shown after adsorption of F(ab') 2 with type Ia polysaccharide-sensitized erythrocytes. Polysaccharide-adsorbed F(ab') 2 had a 70% decrease in ability to block the association of bacteria with PMN. Neuraminidase digestion removed 80% of the terminal sialic acid residues from the native polysaccharide. These neuraminidase-digested organisms had a 72% decrease in binding and transfer of purified C1 compared with non-enzyme-treated organisms. Type Ia capsular polysaccharide bound to sheep erythrocytes promoted classic complement pathway-mediated hemolysis of the cells. The role of C1 inhibitor (INH) in modulation of C1 activation by the organisms was investigated. The possibility existed that the C1 INH could be bound by the bacteria, allowing C1 activation to occur in the fluid phase. The inhibitor was purified from human serum, and its activity was measured before and after incubation with type Ia GBS. The organisms had no effect on C1 INH activity. Thus surface-bound capsular polysacchardie of type Ia GBS mediates C1 binding and classic pathway activation, and this does not involve the C1 INH

  9. Hepatic 123I-insulin binding kinetics in non-insulin-dependent (Type 2) diabetic patients after i.v. bolus administration

    International Nuclear Information System (INIS)

    Oolbekkink, M.; Veen, E.A. van der; Heine, R.J.; Hollander, W. den; Nauta, J.J.P.

    1989-01-01

    Insulin binding kinetics in the liver were studied in non insulin dependent (Type 2) diabetic patients, by i.v. bolus administration of 123 I-insulin. Eight Type 2 diabetic patients were compared with six male volunteers. Uptake of 123 I-insulin by liver and kidneys was measured by dynamic scintigraphy with a gamma camera during 30 min. Images of liver and kidneys appeared within 2-3 min after administration of 123 I-insulin at a dose of 1 mCi (37 MBq). Peak radioactivity for the liver was found 7.5±0.2 and 6.9±0.3 min after injection for the healthy and the diabetic subjects, respectively (N.S.). The percentage 123 I-insulin hepatic uptake was not significantly different for the diabetic and the healthy subjects. Although a large variation exists for maximal uptake of radioactivity within both groups, the data suggest that binding differences in the liver in Type 2 diabetic patients, as compared to healthy subjects, may not account for hepatic insulin resistance. (orig.)

  10. To bind or not to bind? Different temporal binding effects from voluntary pressing and releasing actions.

    Science.gov (United States)

    Zhao, Ke; Chen, Yu-Hsin; Yan, Wen-Jing; Fu, Xiaolan

    2013-01-01

    Binding effect refers to the perceptual attraction between an action and an outcome leading to a subjective compression of time. Most studies investigating binding effects exclusively employ the "pressing" action without exploring other types of actions. The present study addresses this issue by introducing another action, releasing action or the voluntary lifting of the finger/wrist, to investigate the differences between voluntary pressing and releasing actions. Results reveal that releasing actions led to robust yet short-lived temporal binding effects, whereas pressing condition had steady temporal binding effects up to super-seconds. The two actions also differ in sensitivity to changes in temporal contiguity and contingency, which could be attributed to the difference in awareness of action. Extending upon current models of "willed action," our results provide insights from a temporal point of view and support the concept of a dual system consisting of predictive motor control and top-down mechanisms.

  11. Synthesis and antimicrobial, antifungal and anthelmintic activities of 3H-1,5-benzodiazepine derivatives

    Directory of Open Access Journals (Sweden)

    RAJESH KUMAR

    2008-10-01

    Full Text Available The diazonium salt of 4-amino-1-methyl-3-propyl-1H-pyrazole-5-carboxamide in the presence of sodium hydroxide was condensed with different β-diketones/β-ketoesters, 3a–e, to obtain new β-diketones/β-ketoesters, 4a–e. The β-diketones/β-ketoesters 4a–e were condensed with o-phenylenediamine (o-PDA in presence of p-toluenesulfonic acid/SiO2 to give biologically active 3H-1,5-benzodiazepines, 5a–e. All the newly synthesized compounds were characterized by elemental analysis and spectral studies. The compounds 5a–e was screened for their antimicrobial, antifungal and anthelmintic activities.

  12. A 48 kDa collagen-binding phosphoprotein isolated from bovine aortic endothelial cells interacts with the collagenous domain, but not the globular domain, of collagen type IV.

    OpenAIRE

    Yannariello-Brown, J; Madri, J A

    1990-01-01

    We have identified collagen-binding proteins in detergent extracts of metabolically labelled bovine aortic endothelial cells (BAEC) by collagen type IV-Sepharose affinity chromatography. The major collagen type IV-binding protein identified by SDS/PAGE had a molecular mass of 48 kDa, which we term the 'collagen-binding 48 kDa protein' (CB48). The pI of CB48 was 8.0-8.3 in a two-dimensional gel system, running non-equilibrium pH gel electrophoresis in the first dimension and SDS/PAGE in the se...

  13. The endozepine ODN stimulates [3H]thymidine incorporation in cultured rat astrocytes

    International Nuclear Information System (INIS)

    Gandolfo, P.; Patte, C.; Thoumas, J.L.; Leprince, J.; Vaudry, H.; Tonon, M.C.

    1999-01-01

    High concentrations of diazepam-binding inhibitor (DBI) mRNA have been detected in astrocytoma, suggesting that DBI-derived peptides may play a role in glial cell proliferation. In the present study, we have investigated the effect of a processing product of DBI, the octadecaneuropeptide ODN, on DNA synthesis in cultured rat astrocytes. At very low concentrations (10 -14 to 10 -11 M), ODN caused a dose-dependent increase of [ 3 H]thymidine incorporation. At higher doses (10 -10 to 10 -5 M), the effect of ODN gradually declined. The central-type benzodiazepine receptor antagonist flumazenil (10 -6 M) completely suppressed the stimulatory action of ODN whereas the peripheral-type benzodiazepine receptor ligand, PK11195 (10 -6 M) had no effect. The ODN-induced stimulation of [ 3 H]thymidine incorporation was mimicked by methyl 6,7-dimethoxy-4-ethyl-β-carboline-3-carboxylate (DMCM). The GABA A receptor antagonist bicuculline (10 -4 M) suppressed the effect of both ODN and DMCM on DNA synthesis. Exposure of cultured astrocytes to the specific GABA A agonist 3APS (10 -10 to 10 -4 M) also induced a dose-related increase of [ 3 H]thymidine incorporation. The present study indicates that ODN, acting through central-type benzodiazepine receptors associated with the GABA A receptor complex, stimulates DNA synthesis in rat glial cells. These data provide evidence for an autocrine role of endozepines in the control of glial cell proliferation. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  14. Sleep architecture in insomniacs with severe benzodiazepine abuse.

    Science.gov (United States)

    Manconi, Mauro; Ferri, Raffaele; Miano, Silvia; Maestri, Michelangelo; Bottasini, Valentina; Zucconi, Marco; Ferini-Strambi, Luigi

    2017-06-01

    Benzodiazepines (BZDs) are the most commonly prescribed compounds in insomnia. A long-term of BZDs use may cause dependence and abuse. The aim of this study was to evaluate sleep architecture and microstructure (in terms of cyclic alternating pattern - CAP - analysis and of sleep EEG power spectral analysis) in a group of long-term users of high doses of BZDs for their primary chronic insomnia. Twenty patients consecutively admitted at the Sleep Centre for drug discontinuation and 13 matched healthy controls underwent a full nocturnal video-polysomnographic recording, after one adaptation night. Significant differences were found in time in bed, REM sleep latency and sleep stage 1% which were increased in patients compared to controls, while CAP rate was dramatically decreased. During NREM sleep, patients showed a clear decrease in the relative power of delta band. Our data demonstrate that in adults with chronic insomnia, long-term use of high doses of BZDs induces a severe disruption of sleep microstructure, while sleep architecture seems to be much less affected. The long term use of high doses of BZDs for chronic insomnia induces a marked depression of slow wave activity and of its physiological instability. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

  15. The UL5 and UL52 subunits of the herpes simplex virus type 1 helicase-primase subcomplex exhibit a complex interdependence for DNA binding.

    Science.gov (United States)

    Biswas, N; Weller, S K

    2001-05-18

    Herpes simplex virus type 1 encodes a heterotrimeric helicase-primase complex composed of the products of the UL5, UL52, and UL8 genes. The UL5 protein contains seven motifs found in all members of helicase Superfamily 1 (SF1), and the UL52 protein contains several conserved motifs found in primases; however, the contributions of each subunit to the biochemical activities of the subcomplex are not clear. In this work, the DNA binding properties of wild type and mutant subcomplexes were examined using single-stranded, duplex, and forked substrates. A gel mobility shift assay indicated that the UL5-UL52 subcomplex binds more efficiently to the forked substrate than to either single strand or duplex DNA. Although nucleotides are not absolutely required for DNA binding, ADP stimulated the binding of UL5-UL52 to single strand DNA whereas ATP, ADP, and adenosine 5'-O-(thiotriphosphate) stimulated the binding to a forked substrate. We have previously shown that both subunits contact single-stranded DNA in a photocross-linking assay (Biswas, N., and Weller, S. K. (1999) J. Biol. Chem. 274, 8068-8076). In this study, photocross-linking assays with forked substrates indicate that the UL5 and UL52 subunits contact the forked substrates at different positions, UL52 at the single-stranded DNA tail and UL5 near the junction between single-stranded and double-stranded DNA. Neither subunit was able to cross-link a forked substrate when 5-iododeoxyuridine was located within the duplex portion. Photocross-linking experiments with subcomplexes containing mutant versions of UL5 and wild type UL52 indicated that the integrity of the ATP binding region is important for DNA binding of both subunits. These results support our previous proposal that UL5 and UL52 exhibit a complex interdependence for DNA binding (Biswas, N., and Weller, S. K. (1999) J. Biol. Chem. 274, 8068-8076) and indicate that the UL52 subunit may play a more active role in helicase activity than had previously been

  16. Comparison of benzodiazepine receptor and regional cerebral blood flow imagings of epileptiform foci in hippocampal kindled rabbits

    International Nuclear Information System (INIS)

    Kurokawa, Kenzo

    1993-01-01

    To compare the benzodiazepine (Bz) receptor imaging and regional cerebral blood flow (rCBF) imaging in the detection of epileptic foci, the distribution pattern of the Bz receptor and rCBF in hippocampal kindled rabbits was examined by a double tracer autoradiography using ethyl 7-[ 125 I]-5,6-dihydro-5-methyl-6-oxo-4H-imidazo [1, 5-a][1,4] benzodiazepine-3-carboxylate ( 125 I-Ro 16-0154) and 99m Tc-hexamethyl-propyleneamine oxime ( 99m Tc-HMPAO). In visual and quantitative analyses, 125 I-Ro 16-0154 accumulation in brain slices extracted after the completion of the kindling was markedly and extensively decreased in the kindled CA1 region mimicking a primary epileptic focus. 125 I-Ro 16-0154 accumulation was moderately decreased in the ipsilateral temporal lobe, dentate gyrus, CA2, CA4, and bilateral CA3 regions, regarded as the propagated sites of seizure discharges. 99m Tc-HMPAO accumulation was found to be decreased in the ipsilateral CA1, frontal, temporal and dentate gyri. However, the decrease was much more slight and less extensive than that in 125 I-Ro 16-0154 accumulation. These results suggest that Bz receptor imaging is much more sensitive in the detection of epileptic foci than rCBF imaging, and therefore that Bz receptor imaging is useful in clinical epilepsy. (author)

  17. Envelope conformational changes induced by human immunodeficiency virus type 1 attachment inhibitors prevent CD4 binding and downstream entry events.

    Science.gov (United States)

    Ho, Hsu-Tso; Fan, Li; Nowicka-Sans, Beata; McAuliffe, Brian; Li, Chang-Ben; Yamanaka, Gregory; Zhou, Nannan; Fang, Hua; Dicker, Ira; Dalterio, Richard; Gong, Yi-Fei; Wang, Tao; Yin, Zhiwei; Ueda, Yasutsugu; Matiskella, John; Kadow, John; Clapham, Paul; Robinson, James; Colonno, Richard; Lin, Pin-Fang

    2006-04-01

    BMS-488043 is a small-molecule human immunodeficiency virus type 1 (HIV-1) CD4 attachment inhibitor with demonstrated clinical efficacy. The compound inhibits soluble CD4 (sCD4) binding to the 11 distinct HIV envelope gp120 proteins surveyed. Binding of BMS-488043 and that of sCD4 to gp120 are mutually exclusive, since increased concentrations of one can completely block the binding of the other without affecting the maximal gp120 binding capacity. Similarly, BMS-488043 inhibited virion envelope trimers from binding to sCD4-immunoglobulin G (IgG), with decreasing inhibition as the sCD4-IgG concentration increased, and BMS-488043 blocked the sCD4-induced exposure of the gp41 groove in virions. In both virion binding assays, BMS-488043 was active only when added prior to sCD4. Collectively, these results indicate that obstruction of gp120-sCD4 interactions is the primary inhibition mechanism of this compound and that compound interaction with envelope must precede CD4 binding. By three independent approaches, BMS-488043 was further shown to induce conformational changes within gp120 in both the CD4 and CCR5 binding regions. These changes likely prevent gp120-CD4 interactions and downstream entry events. However, BMS-488043 could only partially inhibit CD4 binding to an HIV variant containing a specific envelope truncation and altered gp120 conformation, despite effectively inhibiting the pseudotyped virus infection. Taken together, BMS-488043 inhibits viral entry primarily through altering the envelope conformation and preventing CD4 binding, and other downstream entry events could also be inhibited as a result of these induced conformational changes.

  18. The brain GABA-benzodiazepine receptor alpha-5 subtype in autism spectrum disorder: a pilot [(11)C]Ro15-4513 positron emission tomography study.

    Science.gov (United States)

    Mendez, Maria Andreina; Horder, Jamie; Myers, Jim; Coghlan, Suzanne; Stokes, Paul; Erritzoe, David; Howes, Oliver; Lingford-Hughes, Anne; Murphy, Declan; Nutt, David

    2013-05-01

    GABA (gamma-amino-butyric-acid) is the primary inhibitory neurotransmitter in the human brain. It has been proposed that the symptoms of autism spectrum disorders (ASDs) are the result of deficient GABA neurotransmission, possibly including reduced expression of GABAA receptors. However, this hypothesis has not been directly tested in living adults with ASD. In this preliminary investigation, we used Positron Emission Tomography (PET) with the benzodiazepine receptor PET ligand [(11)C]Ro15-4513 to measure α1 and α5 subtypes of the GABAA receptor levels in the brain of three adult males with well-characterized high-functioning ASD compared with three healthy matched volunteers. We found significantly lower [(11)C]Ro15-4513 binding throughout the brain of participants with ASD (p < 0.0001) compared with controls. Planned region of interest analyses also revealed significant reductions in two limbic brain regions, namely the amygdala and nucleus accumbens bilaterally. Further analysis suggested that these results were driven by lower levels of the GABAA α5 subtype. These results provide initial evidence of a GABAA α5 deficit in ASD and support further investigations of the GABA system in this disorder. This article is part of the Special Issue entitled 'Neurodevelopmental Disorders'. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Genome-Wide Progesterone Receptor Binding: Cell Type-Specific and Shared Mechanisms in T47D Breast Cancer Cells and Primary Leiomyoma Cells

    Science.gov (United States)

    Huang, Lei; Owen, Jonas K.; Xie, Anna; Navarro, Antonia; Monsivais, Diana; Coon V, John S.; Kim, J. Julie; Dai, Yang; Bulun, Serdar E.

    2012-01-01

    Background Progesterone, via its nuclear receptor (PR), exerts an overall tumorigenic effect on both uterine fibroid (leiomyoma) and breast cancer tissues, whereas the antiprogestin RU486 inhibits growth of these tissues through an unknown mechanism. Here, we determined the interaction between common or cell-specific genome-wide binding sites of PR and mRNA expression in RU486-treated uterine leiomyoma and breast cancer cells. Principal Findings ChIP-sequencing revealed 31,457 and 7,034 PR-binding sites in breast cancer and uterine leiomyoma cells, respectively; 1,035 sites overlapped in both cell types. Based on the chromatin-PR interaction in both cell types, we statistically refined the consensus progesterone response element to G•ACA• • •TGT•C. We identified two striking differences between uterine leiomyoma and breast cancer cells. First, the cis-regulatory elements for HSF, TEF-1, and C/EBPα and β were statistically enriched at genomic RU486/PR-targets in uterine leiomyoma, whereas E2F, FOXO1, FOXA1, and FOXF sites were preferentially enriched in breast cancer cells. Second, 51.5% of RU486-regulated genes in breast cancer cells but only 6.6% of RU486-regulated genes in uterine leiomyoma cells contained a PR-binding site within 5 kb from their transcription start sites (TSSs), whereas 75.4% of RU486-regulated genes contained a PR-binding site farther than 50 kb from their TSSs in uterine leiomyoma cells. RU486 regulated only seven mRNAs in both cell types. Among these, adipophilin (PLIN2), a pro-differentiation gene, was induced via RU486 and PR via the same regulatory region in both cell types. Conclusions Our studies have identified molecular components in a RU486/PR-controlled gene network involved in the regulation of cell growth, cell migration, and extracellular matrix function. Tissue-specific and common patterns of genome-wide PR binding and gene regulation may determine the therapeutic effects of antiprogestins in uterine fibroids and

  20. Benzodiazepine prescribing in children under 15 years of age receiving free medical care on the General Medical Services scheme in Ireland.

    LENUS (Irish Health Repository)

    O'Sullivan, K

    2015-06-01

    To examine the prevalence and secular trends in benzodiazepine (BZD) prescribing in the Irish paediatric population. In addition, we examine coprescribing of antiepileptic, antipsychotic, antidepressant and psychostimulants in children receiving BZD drugs and compare BZD prescribing in Ireland to that in other European countries.

  1. Systemic or Intra-Amygdala Infusion of the Benzodiazepine, Midazolam, Impairs Learning, but Facilitates Re-Learning to Inhibit Fear Responses in Extinction

    Science.gov (United States)

    Hart, Genevra; Harris, Justin A.; Westbrook, R. Frederick

    2010-01-01

    A series of experiments used rats to study the effect of a systemic or intra-amygdala infusion of the benzodiazepine, midazolam, on learning and re-learning to inhibit context conditioned fear (freezing) responses. Rats were subjected to two context-conditioning episodes followed by extinction under drug or vehicle, or to two cycles of context…

  2. Structural and binding studies of a C-type galactose-binding lectin from Bothrops jararacussu snake venom.

    Science.gov (United States)

    Sartim, Marco A; Pinheiro, Matheus P; de Pádua, Ricardo A P; Sampaio, Suely V; Nonato, M Cristina

    2017-02-01

    BJcuL is a snake venom galactoside-binding lectin (SVgalL) isolated from Bothrops jararacussu and is involved in a wide variety of biological activities including triggering of pro-inflammatory response, disruption of microbial biofilm structure and induction of apoptosis. In the present work, we determined the crystallographic structure of BJcuL, the first holo structure of a SVgalL, and introduced the fluorescence-based thermal stability assay (Thermofluor) as a tool for screening and characterization of the binding mechanism of SVgalL ligands. BJcuL structure revealed the existence of a porous and flexible decameric arrangement composed of disulfide-linked dimers related by a five-fold symmetry. Each monomer contains the canonical carbohydrate recognition domain, a calcium ion required for BJcuL lectinic activity and a sodium ion required for protein stabilization. BJcuL thermostability was found to be induced by calcium ion and galactoside sugars which exhibit hyperbolic saturation profiles dependent on ligand concentration. Serendipitously, the gentamicin group of aminoglycoside antibiotics (gAGAs) was also identified as BJcuL ligands. On contrast, gAGAs exhibited a sigmoidal saturation profile compatible with a cooperative mechanism of binding. Thermofluor, hemagglutination inhibition assay and molecular docking strategies were used to identify a distinct binding site in BJcuL localized at the dimeric interface near the fully conserved intermolecular Cys86-Cys86 disulfide bond. The hybrid approach used in the present work provided novel insights into structural behavior and functional diversification of SVgaLs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Synthesis of Heparan Sulfate with Cyclophilin B-binding Properties Is Determined by Cell Type-specific Expression of Sulfotransferases*

    Science.gov (United States)

    Deligny, Audrey; Denys, Agnès; Marcant, Adeline; Melchior, Aurélie; Mazurier, Joël; van Kuppevelt, Toin H.; Allain, Fabrice

    2010-01-01

    Cyclophilin B (CyPB) induces migration and adhesion of T lymphocytes via a mechanism that requires interaction with 3-O-sulfated heparan sulfate (HS). HS biosynthesis is a complex process with many sulfotransferases involved. N-Deacetylases/N-sulfotransferases are responsible for N-sulfation, which is essential for subsequent modification steps, whereas 3-O-sulfotransferases (3-OSTs) catalyze the least abundant modification. These enzymes are represented by several isoforms, which differ in term of distribution pattern, suggesting their involvement in making tissue-specific HS. To elucidate how the specificity of CyPB binding is determined, we explored the relationships between the expression of these sulfotransferases and the generation of HS motifs with CyPB-binding properties. We demonstrated that high N-sulfate density and the presence of 2-O- and 3-O-sulfates determine binding of CyPB, as evidenced by competitive experiments with heparin derivatives, soluble HS, and anti-HS antibodies. We then showed that target cells, i.e. CD4+ lymphocyte subsets, monocytes/macrophages, and related cell lines, specifically expressed high levels of NDST2 and 3-OST3 isoforms. Silencing the expression of NDST1, NDST2, 2-OST, and 3-OST3 by RNA interference efficiently decreased binding and activity of CyPB, thus confirming their involvement in the biosynthesis of binding sequences for CyPB. Moreover, we demonstrated that NDST1 was able to partially sulfate exogenous substrate in the absence of NDST2 but not vice versa, suggesting that both isoenzymes do not have redundant activities but do have rather complementary activities in making N-sulfated sequences with CyPB-binding properties. Altogether, these results suggest a regulatory mechanism in which cell type-specific expression of certain HS sulfotransferases determines the specific binding of CyPB to target cells. PMID:19940140

  4. Synthesis of heparan sulfate with cyclophilin B-binding properties is determined by cell type-specific expression of sulfotransferases.

    Science.gov (United States)

    Deligny, Audrey; Denys, Agnès; Marcant, Adeline; Melchior, Aurélie; Mazurier, Joël; van Kuppevelt, Toin H; Allain, Fabrice

    2010-01-15

    Cyclophilin B (CyPB) induces migration and adhesion of T lymphocytes via a mechanism that requires interaction with 3-O-sulfated heparan sulfate (HS). HS biosynthesis is a complex process with many sulfotransferases involved. N-Deacetylases/N-sulfotransferases are responsible for N-sulfation, which is essential for subsequent modification steps, whereas 3-O-sulfotransferases (3-OSTs) catalyze the least abundant modification. These enzymes are represented by several isoforms, which differ in term of distribution pattern, suggesting their involvement in making tissue-specific HS. To elucidate how the specificity of CyPB binding is determined, we explored the relationships between the expression of these sulfotransferases and the generation of HS motifs with CyPB-binding properties. We demonstrated that high N-sulfate density and the presence of 2-O- and 3-O-sulfates determine binding of CyPB, as evidenced by competitive experiments with heparin derivatives, soluble HS, and anti-HS antibodies. We then showed that target cells, i.e. CD4+ lymphocyte subsets, monocytes/macrophages, and related cell lines, specifically expressed high levels of NDST2 and 3-OST3 isoforms. Silencing the expression of NDST1, NDST2, 2-OST, and 3-OST3 by RNA interference efficiently decreased binding and activity of CyPB, thus confirming their involvement in the biosynthesis of binding sequences for CyPB. Moreover, we demonstrated that NDST1 was able to partially sulfate exogenous substrate in the absence of NDST2 but not vice versa, suggesting that both isoenzymes do not have redundant activities but do have rather complementary activities in making N-sulfated sequences with CyPB-binding properties. Altogether, these results suggest a regulatory mechanism in which cell type-specific expression of certain HS sulfotransferases determines the specific binding of CyPB to target cells.

  5. The necessity of connection structures in neural models of variable binding.

    Science.gov (United States)

    van der Velde, Frank; de Kamps, Marc

    2015-08-01

    In his review of neural binding problems, Feldman (Cogn Neurodyn 7:1-11, 2013) addressed two types of models as solutions of (novel) variable binding. The one type uses labels such as phase synchrony of activation. The other ('connectivity based') type uses dedicated connections structures to achieve novel variable binding. Feldman argued that label (synchrony) based models are the only possible candidates to handle novel variable binding, whereas connectivity based models lack the flexibility required for that. We argue and illustrate that Feldman's analysis is incorrect. Contrary to his conclusion, connectivity based models are the only viable candidates for models of novel variable binding because they are the only type of models that can produce behavior. We will show that the label (synchrony) based models analyzed by Feldman are in fact examples of connectivity based models. Feldman's analysis that novel variable binding can be achieved without existing connection structures seems to result from analyzing the binding problem in a wrong frame of reference, in particular in an outside instead of the required inside frame of reference. Connectivity based models can be models of novel variable binding when they possess a connection structure that resembles a small-world network, as found in the brain. We will illustrate binding with this type of model with episode binding and the binding of words, including novel words, in sentence structures.

  6. Analysis of specific 3H-diazepam binding in the brain of emotionally difference mice

    International Nuclear Information System (INIS)

    Blednov, Yu.A.; Gordei, M.L.; Seredenin, S.B.

    1987-01-01

    A study of the behavior of inbred animals under conditions of emotional stress, of the biochemical parameters of the stress reaction, and of the effects of benzodiazepine tranquilizers, conducted in the authors' laboratory, showed that the character of the response to stress and the manifestation of the action of benzodiazepine depend on hereditary factors. The aim of this investigation was to study reception of tritium-labelled diazepam by brain cell membranes of C57BL/6 and BALB/c mice

  7. Systemic injection of kainic acid: Gliosis in olfactory and limbic brain regions quantified with [3H]PK 11195 binding autoradiography

    International Nuclear Information System (INIS)

    Altar, C.A.; Baudry, M.

    1990-01-01

    Neurodegenerative diseases may result from excessive stimulation of excitatory amino acid receptors by endogenous ligands. Because neuronal degeneration is associated with glial proliferation and hypertrophy, the degenerative changes throughout rat brain following the systemic administration of kainic acid (12 mg/kg) were mapped with quantitative autoradiography of [3H]PK 11195. This radioligand binds to a mitochondrial benzodiazepine binding site (MBBS) on microglia and astrocytes. Analysis of eight horizontal and four coronal brain levels revealed up to 16-fold increases in [3H]PK 11195 binding from 1 to 5 weeks but not 1 day after kainate injection. Increases in [3H]PK 11195 binding were predominantly in ventral limbic brain regions and olfactory projections to neocortical areas, with the olfactory cortex greater than subiculum/CA1 greater than anterior olfactory nucleus, medial thalamic nucleus, and piriform cortex greater than cingulate cortex and rostral hippocampus greater than dentate gyrus, septum, and amygdala greater than entorhinal cortex and temporal cortex. Little or no enhancement of [3H]PK 11195 binding was observed in numerous regions including the caudate-putamen, substantia nigra, nucleus accumbens, olfactory tubercle, cerebellum, thalamic nuclei, choroid plexus, medulla, parietal or occipital cortex, or pons. A 2-fold greater extent of neurodegeneration was obtained in ventral portions of the olfactory bulb, entorhinal cortex, temporal cortex, and dentate gyrus compared with the dorsal portions of these structures. The pattern of increase in [3H]PK 11195 binding closely matched the patterns of neuronal degeneration reported following parenteral kainate injection. These findings strengthen the notion that quantitative autoradiography of [3H]PK 11195 is a valuable tool to quantify the extent of neuronal degeneration

  8. Experiment K-6-18. Study of muscarinic and gaba (benzodiazepine) receptors in the sensory-motor cortex, hippcampus and spinal code

    Science.gov (United States)

    Daunton, N.; Damelio, F.; Krasnov, I.

    1990-01-01

    Frontal lobe samples of rat brains flown aboard Cosmos 1887 were processed for the study of muscarinic (cholinergic) and GABA (benzodiazepine) receptors and for immunocytochemical localization of the neurotransmitter gamma-aminobutyric acid (GABA) and glial fibrillary acidic protein (GFAP). Although radioactive labeling of both muscarinic cholinergic and GABA (benzodiazepine) receptors proved to be successful with the techniques employed, distinct receptor localization of individual laminae of the frontal neocortex was not possible since the sampling of the area was different in the various groups of animals. In spite of efforts made for proper orientation and regional identification of laminae, it was found that a densitometric (quantitation of autoradiograms) analysis of the tissue did not contribute to the final interpretation of the effects of weightlessness on these receptors. As to the immunocytochemical studies the use of both markers, GFAP and GABA antiserum, confirmed the suitability of the techniques for use in frozen material. However, similar problems to those encountered in the receptor studies prevented an adequate interpretation of the effects of micro-G exposure on the localization and distribution of GABA and GFAP. This study did, however, confirm the feasibility of investigating neurotransmitters and their receptors in future space flight experiments.

  9. Effects of chronic delta-9-tetrahydrocannabinol (THC) administration on neurotransmitter concentrations and receptor binding in the rat brain

    International Nuclear Information System (INIS)

    Ali, S.F.; Newport, G.D.; Scallet, A.C.; Gee, K.W.; Paule, M.G.; Brown, R.M.; Slikker, W. Jr.

    1989-01-01

    THC is the major psychoactive constituent of marijuana and is also known as an hallucinogenic compound. Numerous reports have shown that large doses of THC produce significant alterations in various neurotransmitter systems. The present study was designed to determine whether chronic exposure to THC produces significant alterations in selected neurotransmitter systems (dopamine, serotonin, acetylcholine, GABAergic, benzodiazepine, and opiate) in the rat brain. In Experiment 1, male Sprague-Dawley rats were gavaged with vehicle, 10 or 20 mg THC/kg body weight daily, 5 days/week for 90 days. Animals were killed either 24 hours or two months after the last dose. Brains were dissected into different regions for neurochemical analyses. Two months after the cessation of chronic administration, there was a significant decrease in GABA receptor binding in the hippocampus of animals in the high dose group. However, no other significant changes were found in neurotransmitter receptor binding characteristics in the hippocampus or in neurotransmitter concentrations in the caudate nucleus, hypothalamus or septum after chronic THC administration. In an attempt to replicate the GABA receptor binding changes and also to determine the [35S]TBPS binding in hippocampus, we designed Experiment 2. In this experiment, we dosed the animals by gavage with 0, 5, 10 or 20 mg THC/kg daily, 5 days/week or with 20 mg THC/kg Monday through Thursday and 60 mg/kg on Friday for 90 days. Results from this experiment failed to replicate the dose-dependent effect of THC on GABA receptor binding in hippocampus. Modulation of [35S]TBPS binding by GABA or 3 alpha-OH-DHP or inhibition by cold TBPS in frontal cortex did not show any significant dose-related effects

  10. Gentamicin binds to the megalin receptor as a competitive inhibitor using the common ligand binding motif of complement type repeats

    DEFF Research Database (Denmark)

    Dagil, Robert; O'Shea, Charlotte; Nykjær, Anders

    2013-01-01

    megalin and investigated its interaction with gentamicin. Using NMR titration data in HADDOCK, we have generated a three-dimensional model describing the complex between megalin and gentamicin. Gentamicin binds to megalin with low affinity and exploits the common ligand binding motif previously described...... to megalin is highly similar to gentamicin binding to calreticulin. We discuss the impact of this novel insight for the future structure-based design of gentamicin antagonists....

  11. Regional increases in [{sup 11}C]flumazenil binding after epilepsy surgery

    Energy Technology Data Exchange (ETDEWEB)

    Savic, I. [Huddinge Hospital, Dept. of Neurology (Sweden); Blomqvist, G. [Karolinska Hospital, Dept. of Clinical Neurophysiology, Stockholm (Sweden); Halldin, C. [Karolinska Hospital, Dept. of Psychiatry, Stockholm (Sweden); Litton, J.E. [Karolinska Hospital, Dept. of Psychology, Stockholm (Sweden); Gulyas, B. [Karolinska Institute, Div. of Human Brain Research (Sweden)

    1998-05-01

    Introduction - Animal experiments suggest that epileptic seizures alter the expression of mRNA for neuro-receptors. PET measurements with [{sup 11}C]flumazenil show that patients with partial seizures have a reduced density of benzodiazepine (BZ) receptors in the epileptogenic regions (ER) and some of the target areas for seizure activity, the so called projection areas. Recent data suggest that the degree of BZ receptor reduction in ER is correlated to seizure frequency. We therefore hypothesized that seizure activity can alter the BZ receptor binding, and that some of these changes could normalize when the seizures disappeared. Methods - In 4 patients whose seizures were generated by mesial temporal lobe structures, BZ receptor density was measured with [{sup 11}C]flumazenil PET before, and 1 year after the epilepsy surgery and cessation of seizures. By use of a computerized anatomical brain atlas the same regions were analyzed in both PET scans, and the results related to data from 7 healthy controls. Results - Presurgical PET scans showed reductions in BZ receptor density in the epileptogenic regions and some of its primary projection areas. Other cortical regions had normal values. Postsurgically, the calculated BZ receptor density normalized (29{+-}17% increase) in several of the affected projection areas, whereas the values in other cortical regions remained unaltered. Conclusion - Regional reductions in BZ receptor density may be dynamic and related to seizures. The present preliminary observations encourage further studies on seizure-related changes in regional receptor binding in humans. (au) 41 refs.

  12. Binding characteristics of 9-fluoropropyl-(+)-dihydrotetrabenzazine (AV-133) to the vesicular monoamine transporter type 2 in rats

    Energy Technology Data Exchange (ETDEWEB)

    Tsao, H.-H. [Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan, Taiwan (China); Lin, K.-J. [Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan, Taiwan (China); Department of Nuclear Medicine, Chang Gung University and Memorial Hospital, Taoyuan, Taiwan (China); Juang, J.-H. [Division of Endocrinology and Metabolism, Chung Gung University and Chung Gung Memorial Hospital, Taoyuan, Taiwan (China); Skovronsky, Daniel M. [Avid Radiopharmaceuticals, Philadelphia, PA (United States); Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Yen, T.-C. [Department of Nuclear Medicine, Chang Gung University and Memorial Hospital, Taoyuan, Taiwan (China); Wey, S.-P. [Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan, Taiwan (China); Kung, M.-P. [Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan, Taiwan (China); Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States)], E-mail: kungmp@sunmac.spect.upenn.edu

    2010-05-15

    The vesicular monoamine transporter type 2 (VMAT2) is highly expressed in pancreatic {beta}-cells and thus has been proposed to be a potential target for measuring {beta}-cell mass (BCM) by molecular imaging. C-11- and F-18-labeled tetrabenazine derivatives targeting VMAT2 have shown some promising results as potential biomarkers for BCM. In the present study, we examined the binding characteristics of 9-fluoropropyl-(+)-dihydrotetrabenzazine ([{sup 18}F]AV-133), a potential PET tracer for BCM imaging, in rat pancreas and rat brain. Methods: Pancreatic exocrine cells and pancreatic islet cells were isolated and purified from Sprague-Dawley rats. Membrane homogenates, prepared from both pancreatic exocrine and islet cells as well as from brain striatum and hypothalamus regions, were used for in vitro binding studies. In vitro and ex vivo autoradiography studies with [{sup 18}F]AV-133 were performed on rat brain and rat pancreas sections. Immunohistochemistry studies were performed to confirm the distribution of VMAT2 on islet {beta}-cells. Results: Excellent binding affinities of [{sup 18}F]AV-133 were observed in rat striatum and hypothalamus homogenates with K{sub d} values of 0.19 and 0.25 nM, respectively. In contrast to single-site binding observed in rat striatum homogenates, rat islet cell homogenates showed two saturable binding sites (site A: K{sub d}=6.76 nM, B{sub max}=60 fmol/mg protein; site B: K{sub d}=241 nM, B{sub max}=1500 fmol/mg protein). Rat exocrine pancreas homogenates showed only a single low-affinity binding site (K{sub d}=209 nM), which was similar to site B in islet cells. In vitro autoradiography of [{sup 18}F]AV-133 using frozen sections of rat pancreas showed specific labeling of islets, as evidenced by co-localization with anti-insulin antibody. Ex vivo VMAT2 pancreatic autoradiography in the rat, however, was not successful, in contrast to the excellent ex vivo autoradiography of VMAT2 binding sites in the brain. In vivo/ex vivo islet

  13. Evaluation of a radiolabelled peripheral benzodiazepine receptor ligand in the central nervous system inflammation of experimental autoimmune encephalomyelitis: a possible probe for imaging multiple sclerosis

    International Nuclear Information System (INIS)

    Mattner, F.; Katsifis, A.; Ballantyne, P.; Staykova, M.; Willenborg, D.O.

    2005-01-01

    Peripheral benzodiazepine receptors (PBRs) are upregulated on macrophages and activated microglia, and radioligands for the PBRs can be used to detect in vivo neuroinflammatory changes in a variety of neurological insults, including multiple sclerosis. Substituted 2-phenyl imidazopyridine-3-acetamides with high affinity and selectivity for PBRs have been prepared that are suitable for radiolabelling with a number of positron emission tomography and single-photon emission computed tomography (SPECT) isotopes. In this investigation, the newly developed high-affinity PBR ligand 6-chloro-2-(4'-iodophenyl)-3-(N,N-diethyl)imidazo [1,2-a]pyridine-3-acetamide, or CLINDE, was radiolabelled with 123 I and its biodistribution in the central nervous system (CNS) of rats with experimental autoimmune encephalomyelitis (EAE) evaluated. EAE was induced in male Lewis rats by injection of an emulsion of myelin basic protein and incomplete Freund's adjuvant containing Mycobacterium butyricum. Biodistribution studies with 123 I-CLINDE were undertaken on EAE rats exhibiting different clinical disease severity and compared with results in controls. Disease severity was confirmed by histopathology in the spinal cord of rats. The relationship between inflammatory lesions and PBR ligand binding was investigated using ex vivo autoradiography and immunohistochemistry on rats with various clinical scores. 123 I-CLINDE uptake was enhanced in the CNS of all rats exhibiting EAE when compared to controls. Binding reflected the ascending nature of EAE inflammation, with lumbar/sacral cord > thoracic cord > cervical cord > medulla. The amount of ligand binding also reflected the clinical severity of disease. Ex vivo autoradiography and immunohistochemistry revealed a good spatial correspondence between radioligand signal and foci of inflammation and in particular ED-1 + cells representing macrophages and microglia. These results demonstrate the ability of 123 I-CLINDE to measure in vivo

  14. Effects of temperature on the p53-DNA binding interactions and their dynamical behavior: comparing the wild type to the R248Q mutant.

    Directory of Open Access Journals (Sweden)

    Khaled Barakat

    Full Text Available BACKGROUND: The protein p53 plays an active role in the regulation of cell cycle. In about half of human cancers, the protein is inactivated by mutations located primarily in its DNA-binding domain. Interestingly, a number of these mutations possess temperature-induced DNA-binding characteristics. A striking example is the mutation of Arg248 into glutamine or tryptophan. These mutants are defective for binding to DNA at 310 K although they have been shown to bind specifically to several p53 response elements at sub-physiological temperatures (298-306 K. METHODOLOGY/PRINCIPAL FINDINGS: This important experimental finding motivated us to examine the effects of temperature on the structure and configuration of R248Q mutant and compare it to the wild type protein. Our aim is to determine how and where structural changes of mutant variants take place due to temperature changes. To answer these questions, we compared the mutant to the wild-type proteins from two different aspects. First, we investigated the systems at the atomistic level through their DNA-binding affinity, hydrogen bond networks and spatial distribution of water molecules. Next, we assessed changes in their long-lived conformational motions at the coarse-grained level through the collective dynamics of their side-chain and backbone atoms separately. CONCLUSIONS: The experimentally observed effect of temperature on the DNA-binding properties of p53 is reproduced. Analysis of atomistic and coarse-grained data reveal that changes in binding are determined by a few key residues and provide a rationale for the mutant-loss of binding at physiological temperatures. The findings can potentially enable a rescue strategy for the mutant structure.

  15. [Ion-dependency of the GABA-potentiating effects of benzodiazepine tranquilizers and harmane].

    Science.gov (United States)

    Abramets, I I; Komissarov, I V

    1984-06-01

    Experiments on an isolated spinal cord of 8-15-day-old rats have shown that one of the possible mechanisms of the GABA-potentiating action of the benzodiazepine tranquilizer, chlorodiazepoxide, may be a decrease in the intraneuronal concentration of Ca2+. This is evidenced by the enhancement of the GABA-potentiating action of chlorodiazepoxide under Ca2+ deficiency in the medium and in the presence of the blockers of the voltage-dependent Ca2+ ionic channels--Mn2+ and Co2+, and by the reduction of the effect in question under Ca2+ excess in the medium and in the presence of the K+ channels blockers--tetraethylammonium and 4-aminopyridine. The GABA-potentiating action of harmane is likely to be related to the blockade of the voltage-dependent K+ channels and elevation of the intracellular concentration of Ca2+.

  16. Benzodiazepine temazepam suppresses the transient auditory 40-Hz response amplitude in humans.

    Science.gov (United States)

    Jääskeläinen, I P; Hirvonen, J; Saher, M; Pekkonen, E; Sillanaukee, P; Näätänen, R; Tiitinen, H

    1999-06-18

    To discern the role of the GABA(A) receptors in the generation and attentive modulation of the transient auditory 40-Hz response, the effects of the benzodiazepine temazepam (10 mg) were studied in 10 healthy social drinkers, using a double-blind placebo-controlled design. Three hundred Hertz standard and 330 Hz rare deviant tones were presented to the left, and 1000 Hz standards and 1100 Hz deviants to the right ear of the subjects. Subjects attended to a designated ear and were to detect deviants therein while ignoring tones to the other. Temazepam significantly suppressed the amplitude of the 40-Hz response, the effect being equal for attended and non-attended tone responses. This suggests involvement of GABA(A) receptors in transient auditory 40-Hz response generation, however, not in the attentive modulation of the 40-Hz response.

  17. Clonazepam as Agonist Substitution Treatment for Benzodiazepine Dependence: A Case Report

    Directory of Open Access Journals (Sweden)

    Angelo Giovanni Icro Maremmani

    2013-01-01

    Full Text Available Nowadays, the misuse of benzodiazepines (BZDs is a cause for a serious concern among pharmacologically inexperienced patients, whether treated or untreated, that could lead to significant complications, including tolerance, dependence, and addiction. We present a case report in which an Italian patient affected by anxiety disorder and treated with BZDs presented a severe case of dependence on BZDs. We treated him according to an agonist substitution approach, switching from the abused BZD to a slow-onset, long-acting, high potency agonist (clonazepam, and looking at the methadone treatment model as paradigm. We decided to use clonazepam for its pharmacokinetic properties. The advantage of choosing a slow-onset, long-lasting BZD for the treatment of our patient was that it led us to a remarkable improvement in the clinical situation, including the cessation of craving, absence of withdrawal symptoms, reduced anxiety, improvements in social functioning, and a better cognition level.

  18. Silexan, an essential oil from flowers of Lavandula angustifolia, is not recognized as benzodiazepine-like in rats trained to discriminate a diazepam cue.

    Science.gov (United States)

    Silenieks, Leo B; Koch, Egon; Higgins, Guy A

    2013-01-15

    Recently, an essential oil of selected quality produced from the flowering tops of Lavandula angustifolia Mill. by steam distillation (Silexan) has been approved in Germany for the treatment of restlessness in case of anxious mood. Based on the observed clinical effects, it has been speculated that lavender oil may exert benzodiazepine-like action including the known dependence and abuse potential of this class of drugs. Although no evidence for such an activity was generated during the long-standing medicinal use of lavender oil, further preclinical investigations were now conducted to evaluate this potential side effect in more detail. Twelve adult, male, Sprague-Dawley rats were trained to discriminate the benzodiazepine drug diazepam (2 mg/kg i.p.) from saline using a two-lever operant procedure. After approximately 40 training sessions the majority of rats learned the discrimination and pre-treatment with ascending doses of diazepam (0.3-2 mg/kg i.p.) produced a dose related generalization to the diazepam cue. In these same animals Silexan was administered to see if animals recognized the drug as "diazepam-like" i.e. generalized to diazepam or "saline-like". Silexan tested at doses 3-30 mg/kg i.p. produced almost exclusively (>90%) saline-like responding. Also there was no effect of Silexan on response rate, i.e. rate of lever pressing, at any dose suggesting that the test article is well tolerated and does not exert a sedating effect. In sum, Silexan has no diazepam-like interoceptive property in adult, male rats. This suggests that Silexan does not share the potential of benzodiazepines to induce the development of tolerance, dependence and addiction. Copyright © 2012 Elsevier GmbH. All rights reserved.

  19. Two unique ligand-binding clamps of Rhizopus oryzae starch binding domain for helical structure disruption of amylose.

    Directory of Open Access Journals (Sweden)

    Ting-Ying Jiang

    Full Text Available The N-terminal starch binding domain of Rhizopus oryzae glucoamylase (RoSBD has a high binding affinity for raw starch. RoSBD has two ligand-binding sites, each containing a ligand-binding clamp: a polyN clamp residing near binding site I is unique in that it is expressed in only three members of carbohydrate binding module family 21 (CBM21 members, and a Y32/F58 clamp located at binding site II is conserved in several CBMs. Here we characterized different roles of these sites in the binding of insoluble and soluble starches using an amylose-iodine complex assay, atomic force microscopy, isothermal titration calorimetry, site-directed mutagenesis, and structural bioinformatics. RoSBD induced the release of iodine from the amylose helical cavity and disrupted the helical structure of amylose type III, thereby significantly diminishing the thickness and length of the amylose type III fibrils. A point mutation in the critical ligand-binding residues of sites I and II, however, reduced both the binding affinity and amylose helix disruption. This is the first molecular model for structure disruption of the amylose helix by a non-hydrolytic CBM21 member. RoSBD apparently twists the helical amylose strands apart to expose more ligand surface for further SBD binding. Repeating the process triggers the relaxation and unwinding of amylose helices to generate thinner and shorter amylose fibrils, which are more susceptible to hydrolysis by glucoamylase. This model aids in understanding the natural roles of CBMs in protein-glycan interactions and contributes to potential molecular engineering of CBMs.

  20. Endocytosis of Integrin-Binding Human Picornaviruses

    Directory of Open Access Journals (Sweden)

    Pirjo Merilahti

    2012-01-01

    Full Text Available Picornaviruses that infect humans form one of the largest virus groups with almost three hundred virus types. They include significant enteroviral pathogens such as rhino-, polio-, echo-, and coxsackieviruses and human parechoviruses that cause wide range of disease symptoms. Despite the economic importance of picornaviruses, there are no antivirals. More than ten cellular receptors are known to participate in picornavirus infection, but experimental evidence of their role in cellular infection has been shown for only about twenty picornavirus types. Three enterovirus types and one parechovirus have experimentally been shown to bind and use integrin receptors in cellular infection. These include coxsackievirus A9 (CV-A9, echovirus 9, and human parechovirus 1 that are among the most common and epidemic human picornaviruses and bind to αV-integrins via RGD motif that resides on virus capsid. In contrast, echovirus 1 (E-1 has no RGD and uses integrin α2β1 as cellular receptor. Endocytosis of CV-A9 has recently been shown to occur via a novel Arf6- and dynamin-dependent pathways, while, contrary to collagen binding, E-1 binds inactive β1 integrin and enters via macropinocytosis. In this paper, we review what is known about receptors and endocytosis of integrin-binding human picornaviruses.

  1. The human 64-kDa polyadenylylation factor contains a ribonucleoprotein-type RNA binding domain and unusual auxiliary motifs

    International Nuclear Information System (INIS)

    Takagaki, Yoshio; Manley, J.L.; MacDonald, C.C.; Shenk, T.

    1992-01-01

    Cleavage stimulation factor is one of the multiple factors required for 3'-end cleavage of mammalian pre-mRNAs. The authors have shown previously that this factor is composed of three subunits with estimated molecular masses of 77, 64, and 50 kDa and that the 64-kDa subunit can be UV-cross linked to RNA in a polyadenylylation signal (AAUAAA)-dependent manner. They have now isolated cDNAs encoding the 64-kDa subunit of human cleavage stimulation factor. The 64-kDa subunit contains a ribonucleoprotein-type RNA binding domain in the N-terminal region and a repeat structure in the C-terminal region in which a pentapeptide sequence (consensus MEARA/G) is repeated 12 times and the formation of a long α-helix stabilized by salt bridges is predicted. An ∼270-amino acid segment surrounding this repeat structure is highly enriched in proline and glycine residues (∼20% for each). When cloned 64-kDa subunit was expressed in Escherichia coli, an N-terminal fragment containing the RNA binding domain bound to RNAs in a polyadenylylation-signal-independent manner, suggesting that the RNA binding domain is directly involved in the binding of the 64-kDa subunit to pre-mRNAs

  2. Ropizine concurrently enhances and inhibits [3H] dextromethorpan binding to different structures of the guinea pig brain: Autoradiographic evidence for multiple binding sites

    International Nuclear Information System (INIS)

    Canoll, P.D.; Smith, P.R.; and Musacchio, J.M.

    1990-01-01

    Ropizine produces a simultaneous enhancement and inhibition of [ 3 H] dextromethorphan (DM) high-affinity binding to different areas of the guinea pig brain. These results imply that there are two distinct types of high-affinity [ 3 H]DM binding sites, which are present in variable proportions in different brain structures. The ropizine-enhances [ 3 H]DM binding type was preferentially inhibited by (+)-pentazocine. This is consistent with the presumption that the (+)-pentazocine-sensitive site is identical with the common site for DM and 3-(-3-Hydroxphenyl)-N-(1-propyl)piperidine ((+)-3-PPP). The second binding type, which is inhibited by ropizine and is not so sensitive to (+)- pentazocine, has not been fully characterized. This study demonstrates that the biphasic effects to ropizine are due, at least in part, to the effects of ropizine on two different types of [ 3 H]DM binding sites. However, this study does not rule out that the common DM/(+)-3-PPP site also might be inhibited by higher concentrations of ropizine

  3. Pictorial binding: endeavor to classify

    Directory of Open Access Journals (Sweden)

    Zinchenko S.

    2015-01-01

    Full Text Available The article is devoted to the classification of bindings of the 1-19th centuries with a unique and untypical book binding decoration technique (encaustic, tempera and oil paintings. Analysis of design features, materials and techniques of art decoration made it possible to identify them as a separate type - pictorial bindings and divide them into four groups. The first group consists of Coptic bindings, decorated with icon-painting images in encaustic technique. The second group is made up of leather Western bindings of the 13-14th centuries, which have the decoration and technique of ornamentation close to iconography. The third group involves parchment bindings, ornamentation technique of which is closer to the miniature. The last group comprises bindings of East Slavic origin of the 15-19th centuries, decorated with icon-painting pictures made in the technique of tempera or oil painting. The proposed classification requires further basic research as several specific kinds of bindings have not yet been investigated

  4. Novel modulatory effects of neurosteroids and benzodiazepines on excitatory and inhibitory neurons excitability: a multi-electrode array recording study

    OpenAIRE

    Puia, Giulia; Gullo, Francesca; Dossi, Elena; Lecchi, Marzia; Wanke, Enzo

    2012-01-01

    The balance between glutamate- and GABA-mediated neurotransmission in the brain is fundamental in the nervous system, but it is regulated by the “tonic” release of a variety of endogenous factors. One such important group of molecules are the neurosteroids (NSs) which, similarly to benzodiazepines (BDZs), enhance GABAergic neurotransmission. The purpose of our work was to investigate, at in vivo physiologically relevant concentrations, the effects of NSs and BDZs as GABA modulators on dissoci...

  5. Characterisation of the binding of [3H]methyllycaconitine: a new radioligand for labelling α7-type neuronal nicotinic acetylcholine receptors

    International Nuclear Information System (INIS)

    Davies, A.R.L.; Wolstenholme, A.J.; Wonnacott, S.; Hardick, D.J.; Blagbrough, I.S.; Potter, B.V.L.

    1999-01-01

    Methyllycaconitine (MLA), a norditerpenoid alkaloid isolated from Delphinium seeds, is one of the most potent non-proteinacious ligands that is selective for αbungarotoxin-sensitive neuronal nicotinic acetylcholine receptors (nAChR). [ 3 H]MLA bound to rat brain membranes with high affinity (K d =1.86±0.31 nM) with a good ratio of specific to non-specific binding. The binding of [ 3 H]MLA was characterised by rapid association (t 1/2 =2.3 min) and dissociation (t 1/2 =12.6 min) kinetics. The radioligand binding displayed nicotinic pharmacology, consistent with an interaction with αbungarotoxin-sensitive nAChR. The snake α-toxins, αbungarotoxin and αcobratoxin, displaced [ 3 H]MLA with high affinity (K i =1.8±0.5 and 5.5±0.9 nM, respectively), whereas nicotine was less potent (K i =6.1±1.1 μM). The distribution of [ 3 H]MLA binding sites in crudely dissected rat brain regions was identical to that of [ 125 I]αbungarotoxin binding sites, with a high binding site density in hippocampus and hypothalamus, but low density in striatum and cerebellum. [ 3 H]MLA also labelled a sub-population of binding sites which are not sensitive to the snake αtoxins, but which did not differ significantly from the major population with respect to their other pharmacological properties or regional distribution. [ 3 H]MLA, therefore, is a novel radiolabel for characterising α7-type nAChR. A good signal to noise ratio and rapid binding kinetics provide advantages over the use of radiolabelled αbungarotoxin for rapid and accurate equilibrium binding assays. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  6. Synthetic LPS-Binding Polymer Nanoparticles

    Science.gov (United States)

    Jiang, Tian

    Lipopolysaccharide (LPS), one of the principal components of most gram-negative bacteria's outer membrane, is a type of contaminant that can be frequently found in recombinant DNA products. Because of its strong and even lethal biological effects, selective LPS removal from bioproducts solution is of particular importance in the pharmaceutical and health care industries. In this thesis, for the first time, a proof-of-concept study on preparing LPS-binding hydrogel-like NPs through facile one-step free-radical polymerization was presented. With the incorporation of various hydrophobic (TBAm), cationic (APM, GUA) monomers and cross-linkers (BIS, PEG), a small library of NPs was constructed. Their FITC-LPS binding behaviors were investigated and compared with those of commercially available LPS-binding products. Moreover, the LPS binding selectivity of the NPs was also explored by studying the NPs-BSA interactions. The results showed that all NPs obtained generally presented higher FITC-LPS binding capacity in lower ionic strength buffer than higher ionic strength. However, unlike commercial poly-lysine cellulose and polymyxin B agarose beads' nearly linear increase of FITC-LPS binding with particle concentration, NPs exhibited serious aggregation and the binding quickly saturated or even decreased at high particle concentration. Among various types of NPs, higher FITC-LPS binding capacity was observed for those containing more hydrophobic monomers (TBAm). However, surprisingly, more cationic NPs with higher content of APM exhibited decreased FITC-LPS binding in high ionic strength conditions. Additionally, when new cationic monomer and cross-linker, GUA and PEG, were applied to replace APM and BIS, the obtained NPs showed improved FITC-LPS binding capacity at low NP concentration. But compared with APM- and BIS-containing NPs, the FITC-LPS binding capacity of GUA- and PEG-containing NPs saturated earlier. To investigate the NPs' binding to proteins, we tested the NPs

  7. Radiosynthesis and initial evaluation of [{sup 18}F]-FEPPA for PET imaging of peripheral benzodiazepine receptors

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Alan A. [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Department of Psychiatry, University of Toronto, Toronto, Ontario, M5T 1R8 (Canada)], E-mail: alan.wilson@camhpet.ca; Garcia, Armando; Parkes, Jun [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); McCormick, Patrick [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Institute of Medical Science, University of Toronto, Toronto, Ontario, M5S 1A8 (Canada); Stephenson, Karin A. [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Houle, Sylvain; Vasdev, Neil [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Department of Psychiatry, University of Toronto, Toronto, Ontario, M5T 1R8 (Canada)

    2008-04-15

    Introduction: A novel [{sup 18}F]-radiolabelled phenoxyanilide, [{sup 18}F]-FEPPA, has been synthesized and evaluated, in vitro and ex vivo, as a potential positron emission tomography imaging agent for the peripheral benzodiazepine receptor (PBR). Methods: [{sup 18}F]-FEPPA and two other radiotracers for imaging PBR, namely [{sup 11}C]-PBR28 and [{sup 11}C]-PBR28-d3, were synthesised and evaluated in vitro and ex vivo as potential PBR imaging agents. Results: [{sup 18}F]-FEPPA is efficiently prepared in one step from its tosylate precursor and [{sup 18}F]-fluoride in high radiochemical yields and at high specific activity. FEPPA displayed a K{sub i} of 0.07 nM for PBR in rat mitochondrial membrane preparations and a suitable lipophilicity for brain penetration (log P of 2.99 at pH 7.4). Upon intravenous injection into rats, [{sup 18}F]-FEPPA showed moderate brain uptake [standard uptake value (SUV) of 0.6 at 5 min] and a slow washout (SUV of 0.35 after 60 min). Highest uptake of radioactivity was seen in the hypothalamus and olfactory bulb, regions previously reported to be enriched in PBR in rat brain. Analysis of plasma and brain extracts demonstrated that [{sup 18}F]-FEPPA was rapidly metabolized, but no lipophilic metabolites were observed in either preparation and only 5% radioactive metabolites were present in brain tissue extracts. Blocking studies to determine the extent of specific binding of [{sup 18}F]-FEPPA in rat brain were problematic due to large perturbations in circulating radiotracer and the lack of a reference region. Conclusions: Further evaluation of the potential of [{sup 18}F]-FEPPA will require the employment of rigorous kinetic models and/or appropriate animal models.

  8. Maltose-binding protein effectively stabilizes the partially closed conformation of the ATP-binding cassette transporter MalFGK2

    KAUST Repository

    Weng, Jingwei; Gu, Shuo; Gao, Xin; Huang, Xuhui; Wang, Wenning

    2017-01-01

    Maltose transporter MalFGK2 is a type-I importer in the ATP-binding cassette (ABC) transporter superfamily. Upon the binding of its periplasmic binding protein, MalE, the ATPase activity of MalFGK2 can be greatly enhanced. Crystal structures of the MalFGK2-MalE-maltose complex in a so-called

  9. Maltose-binding protein effectively stabilizes the partially closed conformation of the ATP-binding cassette transporter MalFGK2

    KAUST Repository

    Weng, Jingwei

    2017-02-23

    Maltose transporter MalFGK2 is a type-I importer in the ATP-binding cassette (ABC) transporter superfamily. Upon the binding of its periplasmic binding protein, MalE, the ATPase activity of MalFGK2 can be greatly enhanced. Crystal structures of the MalFGK2-MalE-maltose complex in a so-called

  10. Genetic evidence that raised sex hormone binding globulin (SHBG) levels reduce the risk of type 2 diabetes

    DEFF Research Database (Denmark)

    Perry, John R B; Weedon, Michael N; Langenberg, Claudia

    2009-01-01

    Epidemiological studies consistently show that circulating sex hormone binding globulin (SHBG) levels are lower in type 2 diabetes patients than non-diabetic individuals, but the causal nature of this association is controversial. Genetic studies can help dissect causal directions...... used data from this SNP, or closely correlated SNPs, in 27 657 type 2 diabetes patients and 58 481 controls from 15 studies. We then used data from additional studies to estimate the difference in SHBG levels between type 2 diabetes patients and controls. The SHBG SNP rs1799941 was associated with type...... 2 diabetes [odds ratio (OR) 0.94, 95% CI: 0.91, 0.97; P = 2 x 10(-5)], with the SHBG raising allele associated with reduced risk of type 2 diabetes. This effect was very similar to that expected (OR 0.92, 95% CI: 0.88, 0.96), given the SHBG-SNP versus SHBG levels association (SHBG levels are 0.2...

  11. Dependence and withdrawal reactions to benzodiazepines and sellective serotonin reuptake inhibitors: How did the health authorities react?

    DEFF Research Database (Denmark)

    Nielsen, Margrethe

    2013-01-01

    AIM: Our objective was to explore communications from drug agencies about benzodiazepine dependence and selective serotonin reuptake inhibitors (SSRIs) withdrawal reactions over time. METHODS: Documentary study. We searched the web-sites of the European Medicines Agency and the drug agencies in USA...... it is difficult for many patients to stop treatment. In the perspective of a precautionary principle, drug agencies have failed to acknowledge that SSRIs can cause dependence and have minimised the problem with regard to its frequency and severity. In the perspective of a risk management principle, the drug...

  12. Enhanced binding affinity, remarkable selectivity, and high capacity of CO 2 by dual functionalization of a rht-type metal-organic framework

    KAUST Repository

    Li, Baiyan; Zhang, Zhijuan; Li, Yi; Yao, Kexin; Zhu, Yihan; Deng, Zhiyong; Yang, Fen; Zhou, Xiaojing; Li, Guanghua; Wu, Haohan; Nijem, Nour; Chabal, Yves Jean; Lai, Zhiping; Han, Yu; Shi, Zhan; Feng, Shouhua; Li, Jing

    2011-01-01

    Open and friendly: The smallest member of the rht-type metal-organic frameworks (MOFs, see picture) constructed by a hexacarboxylate ligand with a nitrogen-rich imino triazine backbone shows a significantly enhanced gas binding affinity relative

  13. Factors Affecting the Binding of a Recombinant Heavy Metal-Binding Domain (CXXC motif Protein to Heavy Metals

    Directory of Open Access Journals (Sweden)

    Kamala Boonyodying

    2012-06-01

    Full Text Available A number of heavy metal-binding proteins have been used to study bioremediation. CXXC motif, a metal binding domain containing Cys-X-X-Cys motif, has been identified in various organisms. These proteins are capable of binding various types of heavy metals. In this study, heavy metal binding domain (CXXC motif recombinant protein encoded from mcsA gene of S. aureus were cloned and overexpressed in Escherichia coli. The factors involved in the metal-binding activity were determined in order to analyze the potential of recombinant protein for bioremediation. A recombinant protein can be bound to Cd2+, Co2+, Cu2+ and Zn2+. The thermal stability of a recombinant protein was tested, and the results showed that the metal binding activity to Cu2+ and Zn2+ still exist after treating the protein at 85ºC for 30 min. The temperature and pH that affected the metal binding activity was tested and the results showed that recombinant protein was still bound to Cu2+ at 65ºC, whereas a pH of 3-7 did not affect the metal binding E. coli harboring a pRset with a heavy metal-binding domain CXXC motif increased the resistance of heavy metals against CuCl2 and CdCl2. This study shows that metal binding domain (CXXC motif recombinant protein can be effectively bound to various types of heavy metals and may be used as a potential tool for studying bioremediation.

  14. Backbone and sidechain 1H, 13C and 15N resonance assignments of the human brain-type fatty acid binding protein (FABP7) in its apo form and the holo forms binding to DHA, oleic acid, linoleic acid and elaidic acid

    DEFF Research Database (Denmark)

    Oeemig, Jesper S; Jørgensen, Mathilde L; Hansen, Mikka S

    2009-01-01

    In this manuscript, we present the backbone and side chain assignments of human brain-type fatty acid binding protein, also known as FABP7, in its apo form and in four different holo forms, bound to DHA, oleic acid, linoleic acid and elaidic acid.......In this manuscript, we present the backbone and side chain assignments of human brain-type fatty acid binding protein, also known as FABP7, in its apo form and in four different holo forms, bound to DHA, oleic acid, linoleic acid and elaidic acid....

  15. The N-terminus of porcine circovirus type 2 replication protein is required for nuclear localization and ori binding activities

    International Nuclear Information System (INIS)

    Lin, W.-L.; Chien, M.-S.; Du, Y.-W.; Wu, P.-C.; Huang Chienjin

    2009-01-01

    Porcine circovirus type 2 possesses a circular, single-stranded DNA genome that requires the replication protein (Rep) for virus replication. To characterize the DNA binding potential and the significant region that confers the nuclear localization of the Rep protein, the defined coding regions of rep gene were cloned and expressed. All of the recombinant proteins except for the N-terminal 110 residues deletion mutant could bind to the double-stranded minimal binding site of replication origin (ori). In addition, the N-terminal deletion mutant lacking 110 residues exhibited mainly cytoplasmic staining in the transfected cells in contrast to the others, which localized dominantly in the nucleus, suggesting that this N-terminal domain is essential for nuclear localization. Furthermore, a series of green fluorescence proteins (GFP) containing potential nuclear localization signal (NLS) sequences were tested for their cellular distribution. The ability of the utmost 20 residues of the N-terminal region to target the GFP to the nucleus confirmed its role as a functional NLS.

  16. Bitopic Ligands and Metastable Binding Sites

    DEFF Research Database (Denmark)

    Fronik, Philipp; Gaiser, Birgit I; Sejer Pedersen, Daniel

    2017-01-01

    of orthosteric binding sites. Bitopic ligands have been employed to address the selectivity problem by combining (linking) an orthosteric ligand with an allosteric modulator, theoretically leading to high-affinity subtype selective ligands. However, it remains a challenge to identify suitable allosteric binding...... that have been reported to date, this type of bitopic ligands would be composed of two identical pharmacophores. Herein, we outline the concept of bitopic ligands, review metastable binding sites, and discuss their potential as a new source of allosteric binding sites....

  17. Benzodiazepine Use Among Low Back Pain Patients Concurrently Prescribed Opioids in the Military Health System Between 2012 and 2013

    Science.gov (United States)

    2017-06-16

    CUil:RENITL Y IN UBE CAN BE VS-ED BENZODIAZEPINE USE AMONG LOW BACK PAIN PATIENTS CONCURRENn Y PRESCRJBED OPIOIDS IN THE MILITARY HEAL TH SYSTEM BETWEEN...increases in the amount of opiotds p.rescrtl>ed for chronic non-cancer pain , particularly low back pain , exist amoog those served by the milit:a ry health...be11ZOdiazepine prescribing practices among active duty service members with low back pain . It is important to understand factors associated with

  18. The endozepine ODN stimulates [{sup 3}H]thymidine incorporation in cultured rat astrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Gandolfo, P.; Patte, C.; Thoumas, J.L.; Leprince, J.; Vaudry, H.; Tonon, M.C. [European Institute for Peptide Research (IFRMP no. 23), Laboratory of Cellular and Molecular Neuroendocrinology, INSERM U 413, UA CNRS, University of Rouen, 76821 Mont-Saint-Aignan (France)

    1999-05-15

    High concentrations of diazepam-binding inhibitor (DBI) mRNA have been detected in astrocytoma, suggesting that DBI-derived peptides may play a role in glial cell proliferation. In the present study, we have investigated the effect of a processing product of DBI, the octadecaneuropeptide ODN, on DNA synthesis in cultured rat astrocytes. At very low concentrations (10{sup -14} to 10{sup -11} M), ODN caused a dose-dependent increase of [{sup 3}H]thymidine incorporation. At higher doses (10{sup -10} to 10{sup -5} M), the effect of ODN gradually declined. The central-type benzodiazepine receptor antagonist flumazenil (10{sup -6} M) completely suppressed the stimulatory action of ODN whereas the peripheral-type benzodiazepine receptor ligand, PK11195 (10{sup -6} M) had no effect. The ODN-induced stimulation of [{sup 3}H]thymidine incorporation was mimicked by methyl 6,7-dimethoxy-4-ethyl-{beta}-carboline-3-carboxylate (DMCM). The GABA{sub A} receptor antagonist bicuculline (10{sup -4} M) suppressed the effect of both ODN and DMCM on DNA synthesis. Exposure of cultured astrocytes to the specific GABA{sub A} agonist 3APS (10{sup -10} to 10{sup -4} M) also induced a dose-related increase of [{sup 3}H]thymidine incorporation. The present study indicates that ODN, acting through central-type benzodiazepine receptors associated with the GABA{sub A} receptor complex, stimulates DNA synthesis in rat glial cells. These data provide evidence for an autocrine role of endozepines in the control of glial cell proliferation. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  19. Synthesis of [[sup 123]I]tert-Butyl 8-iodo-5,6-dihydro-5-methyl-6-oxo-4H-imidazo[1,5-a][1,4]benzodiaze pine 3-carboxylate, a potential SPECT imaging agent for diazepam-intensive (DI) benzodiazepine receptors

    Energy Technology Data Exchange (ETDEWEB)

    He, Xiaoshu; Matecka, Dorota; Gu, Ziqiang; Rice, K C; Costa, B.R. de [National Inst. of Diabetes and Digestive and Kidney Diseases, Bethesda, MD (United States); Lee, K S [National Inst. of Mental Health, Washington, DC (United States); Wong, Garry; Skolnick, Phil [National Inst. of Diabetes and Digestive and Kidney Diseases, Bethesda, MD (United States). Lab. of Neuroscience

    1994-01-01

    [[sup 123]I]tert-Butyl 8-iodo-5,6-dihydro-5-methyl-6-oxo-4H-imidazo [1,5-a] [1,4]benzodiazepine 3-carboxylate ([[sup 123]I]3), a high affinity and selective radioligand for the diazepam insensitive (DI) benzodiazepine receptor was synthesized in 2 steps from tert-butyl 8-bromo-5,6-dihydro-5-methyl-6-oxo-4H-imidazo[1,5-a][1,4]benzodiaz epine 3-carboxylate. (Author).

  20. Benzodiazepine-induced anxiolysis and reduction of conditioned fear are mediated by distinct GABAA receptor subtypes in mice

    Science.gov (United States)

    Smith, Kiersten S.; Engin, Elif; Meloni, Edward G.; Rudolph, Uwe

    2012-01-01

    GABAA receptor modulating drugs such as benzodiazepines (BZs) have been used to treat anxiety disorders for over five decades. In order to determine whether the same or different GABAA receptor subtypes are necessary for the anxiolytic-like action of BZs in unconditioned anxiety and conditioned fear models, we investigated the role of different GABAA receptor subtypes by challenging wild type, α1(H101R), α2(H101R) and α3(H126R) mice bred on the C57BL/6J background with diazepam or chlordiazepoxide in the elevated plus maze and the fear-potentiated startle paradigms. Both drugs significantly increased open arm exploration in the elevated plus maze in wild type, α1(H101R) and α3(H126R), but this effect was abolished in α2(H101R) mice; these were expected results based on previous published results. In contrast, while administration of diazepam and chlordiazepoxide significantly attenuated fear-potentiated startle (FPS) in wild type mice and α3(H126R) mice, the fear-reducing effects of these drugs were absent in both α1(H101R) and α2(H101R) point mutants, indicating that both α1- and α2-containing GABAA receptors are necessary for BZs to exert their effects on conditioned fear responses.. Our findings illustrate both an overlap and a divergence between the GABAA receptor subtype requirements for the impact of BZs, specifically that both α1- and α2-containing GABAA receptors are necessary for BZs to reduce conditioned fear whereas only α2-containing GABAA receptors are needed for BZ-induced anxiolysis in unconditioned tests of anxiety. This raises the possibility that GABAergic pharmacological interventions for specific anxiety disorders can be differentially tailored. PMID:22465203