Sample records for ultra-low dose naltrexone

  1. Ultra-low dose naltrexone enhances cannabinoid-induced antinociception.

    PubMed

    Paquette, Jay; Olmstead, Mary C; Olmstead, Mary

    2005-12-01

    Both opioids and cannabinoids have inhibitory effects at micromolar doses, which are mediated by activated receptors coupling to Gi/o-proteins. Surprisingly, the analgesic effects of opioids are enhanced by ultra-low doses (nanomolar to picomolar) of the opioid antagonist, naltrexone. As opioid and cannabinoid systems interact, this study investigated whether ultra-low dose naltrexone also influences cannabinoid-induced antinociception. Separate groups of Long-Evans rats were tested for antinociception following an injection of vehicle, a sub-maximal dose of the cannabinoid agonist WIN 55 212-2, naltrexone (an ultra-low or a high dose) or a combination of WIN 55 212-2 and naltrexone doses. Tail-flick latencies were recorded for 3 h, at 10-min intervals for the first hour, and at 15-min intervals thereafter. Ultra-low dose naltrexone elevated WIN 55 212-2-induced tail flick thresholds without extending its duration of action. This enhancement was replicated in animals receiving intraperitoneal or intravenous injections. A high dose of naltrexone had no effect on WIN 55 212-2-induced tail flick latencies, but a high dose of the cannabinoid 1 receptor antagonist SR 141716 blocked the elevated tail-flick thresholds produced by WIN 55 212-2+ultra-low dose naltrexone. These data suggest a mechanism of cannabinoid-opioid interaction whereby activated opioid receptors that couple to Gs-proteins may attenuate cannabinoid-induced antinociception and/or motor functioning.

  2. Ultra-low dose naltrexone attenuates chronic morphine-induced gliosis in rats.

    PubMed

    Mattioli, Theresa-Alexandra M; Milne, Brian; Cahill, Catherine M

    2010-04-16

    The development of analgesic tolerance following chronic morphine administration can be a significant clinical problem. Preclinical studies demonstrate that chronic morphine administration induces spinal gliosis and that inhibition of gliosis prevents the development of analgesic tolerance to opioids. Many studies have also demonstrated that ultra-low doses of naltrexone inhibit the development of spinal morphine antinociceptive tolerance and clinical studies demonstrate that it has opioid sparing effects. In this study we demonstrate that ultra-low dose naltrexone attenuates glial activation, which may contribute to its effects on attenuating tolerance. Spinal cord sections from rats administered chronic morphine showed significantly increased immuno-labelling of astrocytes and microglia compared to saline controls, consistent with activation. 3-D images of astrocytes from animals administered chronic morphine had significantly larger volumes compared to saline controls. Co-injection of ultra-low dose naltrexone attenuated this increase in volume, but the mean volume differed from saline-treated and naltrexone-treated controls. Astrocyte and microglial immuno-labelling was attenuated in rats co-administered ultra-low dose naltrexone compared to morphine-treated rats and did not differ from controls. Glial activation, as characterized by immunohistochemical labelling and cell size, was positively correlated with the extent of tolerance developed. Morphine-induced glial activation was not due to cell proliferation as there was no difference observed in the total number of glial cells following chronic morphine treatment compared to controls. Furthermore, using 5-bromo-2-deoxyuridine, no increase in spinal cord cell proliferation was observed following chronic morphine administration. Taken together, we demonstrate a positive correlation between the prevention of analgesic tolerance and the inhibition of spinal gliosis by treatment with ultra-low dose naltrexone

  3. The cannabinoid anticonvulsant effect on pentylenetetrazole-induced seizure is potentiated by ultra-low dose naltrexone in mice.

    PubMed

    Bahremand, Arash; Shafaroodi, Hamed; Ghasemi, Mehdi; Nasrabady, Sara Ebrahimi; Gholizadeh, Shervin; Dehpour, Ahmad Reza

    2008-09-01

    Cannabinoid compounds are anticonvulsant since they have inhibitory effects at micromolar doses, which are mediated by activated receptors coupling to G(i/o) proteins. Surprisingly, both the analgesic and anticonvulsant effects of opioids are enhanced by ultra-low doses (nanomolar to picomolar) of the opioid antagonist naltrexone and as opioid and cannabinoid systems interact, it has been shown that ultra-low dose naltrexone also enhances cannabinoid-induced antinociception. Thus, concerning the seizure modulating properties of both classes of receptors this study investigated whether the ultra-low dose opioid antagonist naltrexone influences cannabinoid anticonvulsant effects. The clonic seizure threshold was tested in separate groups of male NMRI mice following injection of vehicle, the cannabinoid selective agonist arachidonyl-2-chloroethylamide (ACEA) and ultra-low doses of the opioid receptor antagonist naltrexone and a combination of ACEA and naltrexone doses in a model of clonic seizure induced by pentylenetetrazole (PTZ). Systemic injection of ultra-low doses of naltrexone (1pg/kg to 1ng/kg, i.p.) significantly potentiated the anticonvulsant effect of ACEA (1mg/kg, i.p.). Moreover, the very low dose of naltrexone (500pg/kg) unmasked a strong anticonvulsant effect for very low doses of ACEA (10 and 100microg/kg). A similar potentiation by naltrexone (500pg/kg) of anticonvulsant effects of non-effective dose of ACEA (1mg/kg) was also observed in the generalized tonic-clonic model of seizure. The present data indicate that the interaction between opioid and cannabinoid systems extends to ultra-low dose levels and ultra-low doses of opioid receptor antagonist in conjunction with very low doses of cannabinoids may provide a potent strategy to modulate seizure susceptibility.

  4. Oxytrex: an oxycodone and ultra-low-dose naltrexone formulation.

    PubMed

    Webster, Lynn R

    2007-08-01

    Oxytrex (Pain Therapeutics, Inc.) is an oral opioid that combines a therapeutic amount of oxycodone with an ultra-low dose of the antagonist naltrexone. Animal data indicate that this combination minimizes the development of physical dependence and analgesic tolerance while prolonging analgesia. Oxytrex is in late-stage clinical development by Pain Therapeutics for the treatment of moderate-to-severe chronic pain. To evaluate the safety and efficacy of the oxycodone/naltrexone combination, three clinical studies have been conducted, one in healthy volunteers and the other two in patients with chronic pain. The putative mechanism of ultra-low-dose naltrexone is to prevent an alteration in G-protein coupling by opioid receptors that is associated with opioid tolerance and dependence. Opioid agonists are initially inhibitory but become excitatory through constant opioid receptor activity. The agonist/antagonist combination of Oxytrex may reduce the conversion from an inhibitory to an excitatory receptor, thereby decreasing the development of tolerance and physical dependence.

  5. Potentiation of buprenorphine antinociception with ultra-low dose naltrexone in healthy subjects.

    PubMed

    Hay, J L; La Vincente, S F; Somogyi, A A; Chapleo, C B; White, J M

    2011-03-01

    Previous reports have demonstrated greater antinociception following administration of a buprenorphine/naloxone combination compared to buprenorphine alone among healthy volunteers. The aim of the current investigation was to determine whether buprenorphine antinociception could be enhanced with the addition of ultra-low dose naltrexone, using a range of dose ratios. A repeated-measures, double-blind, cross-over trial was undertaken with 10 healthy participants. The effects of each buprenorphine:naltrexone ratio (100:1, 133:1, 166:1, and 200:1) on cold pressor tolerance time and respiration were compared to the effects of buprenorphine only. The 166:1 ratio was associated with significantly greater tolerance time to cold pressor pain than buprenorphine alone. Minimal respiratory depression and few adverse events were observed in all conditions. These findings suggest that, as previously described with naloxone, the addition of ultra-low dose naltrexone can enhance the antinociceptive effect of buprenorphine in humans. This potentiation is dose-ratio dependent and occurs without a concomitant increase in adverse effects. Copyright © 2010 European Federation of International Association for the Study of Pain Chapters. Published by Elsevier Ltd. All rights reserved.

  6. Human abuse liability assessment of oxycodone combined with ultra-low-dose naltrexone.

    PubMed

    Tompkins, David Andrew; Lanier, Ryan K; Harrison, Joseph A; Strain, Eric C; Bigelow, George E

    2010-07-01

    Prescription opioid abuse has risen dramatically in the United States as clinicians have increased opioid prescribing for alleviation of both acute and chronic pain. Opioid analgesics with decreased risk for abuse are needed. Preclinical and clinical studies have shown that opioids combined with ultra-low-dose naltrexone (NTX) may have increased analgesic potency and have suggested reduced abuse or dependence liability. This study addressed whether addition of ultra-low-dose naltrexone might decrease the abuse liability of oxycodone (OXY) in humans. This double-blind, placebo-controlled study systematically examined the subjective and physiological effects of combining oral OXY and ultra-low NTX doses in 14 experienced opioid abusers. Seven acute drug conditions given at least 5 days apart were compared in a within-subject crossover design: placebo, OXY 20 mg, OXY 40 mg, plus each of the active OXY doses combined with 0.0001 and 0.001 mg NTX. The methods were sensitive to detecting opioid effects on abuse liability indices, with significant differences between all OXY conditions and placebo as well as between 20 and 40 mg OXY doses on positive subjective ratings (e.g., "I feel a good drug effect" or "I like the drug"), on observer- and participant-rated opioid agonist effects, and on a drug-versus-money value rating. There were no significant differences or evident trends associated with the addition of either NTX dose on any abuse liability indices. The addition of ultra-low-dose NTX to OXY did not decrease abuse liability of acutely administered OXY in experienced opioid abusers.

  7. Tolerance to the anticonvulsant effect of morphine in mice: blockage by ultra-low dose naltrexone.

    PubMed

    Roshanpour, Maryam; Ghasemi, Mehdi; Riazi, Kiarash; Rafiei-Tabatabaei, Neda; Ghahremani, Mohammad Hossein; Dehpour, Ahmad Reza

    2009-02-01

    The present study evaluated the development of tolerance to the anticonvulsant effect of morphine in a mouse model of clonic seizures induced by pentylenetetrazole, and whether ultra-low doses of the opioid receptor antagonist naltrexone which selectively block G(s) opioid receptors were capable of preventing the observed tolerance. The results showed that the morphine anticonvulsant effect could be subject to tolerance after repeated administration. Both the development and expression of tolerance were inhibited by ultra-low doses of naltrexone, suggesting the possible involvement of G(s)-coupled opioid receptors in the development of tolerance to the anticonvulsant effect of morphine.

  8. Oxycodone plus ultra-low-dose naltrexone attenuates neuropathic pain and associated mu-opioid receptor-Gs coupling.

    PubMed

    Largent-Milnes, Tally M; Guo, Wenhong; Wang, Hoau-Yan; Burns, Lindsay H; Vanderah, Todd W

    2008-08-01

    Both peripheral nerve injury and chronic opioid treatment can result in hyperalgesia associated with enhanced excitatory neurotransmission at the level of the spinal cord. Chronic opioid administration leads to a shift in mu-opioid receptor (MOR)-G protein coupling from G(i/o) to G(s) that can be prevented by cotreatment with an ultra-low-dose opioid antagonist. In this study, using lumbar spinal cord tissue from rats with L(5)/L(6) spinal nerve ligation (SNL), we demonstrated that SNL injury induces MOR linkage to G(s) in the damaged (ipsilateral) spinal dorsal horn. This MOR-G(s) coupling occurred without changing G(i/o) coupling levels and without changing the expression of MOR or Galpha proteins. Repeated administration of oxycodone alone or in combination with ultra-low-dose naltrexone (NTX) was assessed on the SNL-induced MOR-G(s) coupling as well as on neuropathic pain behavior. Repeated spinal oxycodone exacerbated the SNL-induced MOR-G(s) coupling, whereas ultra-low-dose NTX cotreatment slightly but significantly attenuated this G(s) coupling. Either spinal or oral administration of oxycodone plus ultra-low-dose NTX markedly enhanced the reductions in allodynia and thermal hyperalgesia produced by oxycodone alone and minimized tolerance to these effects. The MOR-G(s) coupling observed in response to SNL may in part contribute to the excitatory neurotransmission in spinal dorsal horn in neuropathic pain states. The antihyperalgesic and antiallodynic effects of oxycodone plus ultra-low-dose NTX (Oxytrex, Pain Therapeutics, Inc., San Mateo, CA) suggest a promising new treatment for neuropathic pain. The current study investigates whether Oxytrex (oxycodone with an ultra-low dose of naltrexone) alleviates mechanical and thermal hypersensitivities in an animal model of neuropathic pain over a period of 7 days, given locally or systemically. In this report, we first describe an injury-induced shift in mu-opioid receptor coupling from G(i/o) to G(s), suggesting

  9. Ultra-Low Doses of Naltrexone Enhance the Antiallodynic Effect of Pregabalin or Gabapentin in Neuropathic Rats.

    PubMed

    Pineda-Farias, Jorge B; Caram-Salas, Nadia L; Salinas-Abarca, Ana B; Ocampo, Jorge; Granados-Soto, Vinicio

    2017-12-01

    Preclinical Research Treatment of neuropathic pain is an area of largely unmet medical need. Pregabalin and gabapentin are anticonvulsants widely used for the treatment of neuropathic pain. Unfortunately, these drugs are only effective in 50-60% of the treated patients. In addition, both drugs have substantial side effects. Several studies have reported that ultralow doses of opioid receptor antagonists can induce analgesia and enhance the analgesic effect of opioids in rodents and humans. The objective of the present study was to assess the antiallodynic synergistic interaction between gabapentinoids and naltrexone in rats. Oral administration of pregabalin (ED 50  = 2.79 ± 0.16 mg/kg) or gabapentin (ED 50  = 21.04 ± 2.87 mg/kg) as well as intrathecal naltrexone (ED 50  = 0.11 ± 0.02 ng) reduced in a dose-dependent manner tactile allodynia in rats. Maximal antiallodynic effects (∼100%) were reached with 30 mg/kg of pregabalin, 300 mg/kg of gabapentin or 0.5 ng of naltrexone. Co-administration of pregabalin or gabapentin and naltrexone in a fixed-dose ratio (1:1) remarkably reduced spinal nerve ligation-induced tactile allodynia showing a synergistic interaction. The data indicate that combinations of pregabalin or gabapentin and ultra-low doses of naltrexone are able to reduce tactile allodynia in neuropathic rats with lower doses that those used when drugs are given individually and with an improved side effects profile. Drug Dev Res 78 : 371-380, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  10. Oxycodone Plus Ultra-Low-Dose Naltrexone Attenuates Neuropathic Pain and Associated μ-Opioid Receptor–Gs Coupling

    PubMed Central

    Largent-Milnes, Tally M.; Guo, Wenhong; Wang, Hoau-Yan; Burns, Lindsay H.; Vanderah, Todd W.

    2017-01-01

    Both peripheral nerve injury and chronic opioid treatment can result in hyperalgesia associated with enhanced excitatory neurotransmission at the level of the spinal cord. Chronic opioid administration leads to a shift in μ-opioid receptor (MOR)–G protein coupling from Gi/o to Gs that can be prevented by cotreatment with an ultra-low-dose opioid antagonist. In this study, using lumbar spinal cord tissue from rats with L5/L6 spinal nerve ligation (SNL), we demonstrated that SNL injury induces MOR linkage to Gs in the damaged (ipsilateral) spinal dorsal horn. This MOR-Gs coupling occurred without changing Gi/o coupling levels and without changing the expression of MOR or Gα proteins. Repeated administration of oxycodone alone or in combination with ultra-low-dose naltrexone (NTX) was assessed on the SNL-induced MOR-Gs coupling as well as on neuropathic pain behavior. Repeated spinal oxycodone exacerbated the SNL-induced MOR-Gs coupling, whereas ultra-low-dose NTX cotreatment slightly but significantly attenuated this Gs coupling. Either spinal or oral administration of oxycodone plus ultra-low-dose NTX markedly enhanced the reductions in allodynia and thermal hyperalgesia produced by oxycodone alone and minimized tolerance to these effects. The MOR-Gs coupling observed in response to SNL may in part contribute to the excitatory neurotransmission in spinal dorsal horn in neuropathic pain states. The antihyperalgesic and antiallodynic effects of oxycodone plus ultra-low-dose NTX (Oxytrex, Pain Therapeutics, Inc., San Mateo, CA) suggest a promising new treatment for neuropathic pain. PMID:18468954

  11. Does adding low doses of oral naltrexone to morphine alter the subsequent opioid requirements and side effects in trauma patients?

    PubMed

    Farahmand, Shervin; Ahmadi, Omid; Dehpour, Ahmadreza; Khashayar, Patricia

    2012-01-01

    The present study aims to assess the influence of ultra-low doses of opioid antagonists on the analgesic properties of opioids and their side effects. In the present randomized, double-blind controlled trial, the influence of the combination of ultra-low-dose naltrexone and morphine on the total opioid requirement and the frequency of the subsequent side effects was compared with that of morphine alone (added with placebo) in patients with trauma in the upper or lower extremities. Although the morphine and naltrexone group required 0.04 mg more opioids during the study period, there was no significant difference between the opioid requirements of the 2 groups. Nausea was less frequently reported in patients receiving morphine and naltrexone. The combination of ultra-low-dose naltrexone and morphine in extremity trauma does not affect the opioid requirements; it, however, lowers the risk of nausea. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Treatment of Hailey-Hailey Disease With Low-Dose Naltrexone.

    PubMed

    Albers, Lauren N; Arbiser, Jack L; Feldman, Ron J

    2017-10-01

    Hailey-Hailey disease is a severe genetic blistering disease of intertriginous skin locations that can lead to poor quality of life and increased morbidities. Multiple therapies are available with inconsistent outcomes and potentially severe adverse effects. To determine whether low-dose naltrexone is an effective treatment for Hailey-Hailey disease. This study was a case series performed at a dermatology outpatient clinic of 3 patients with severe Hailey-Hailey disease recalcitrant to at least 4 therapies. Low-dose naltrexone, 3 mg nightly, titrated to 4.5 mg nightly in 2 patients. Reduction in size of lesions as well as subjective improvement of symptoms. All 3 patients noted significant healing of erosions and plaques starting from the peripheral aspect within 1 to 2 weeks of treatment, and clinical resolution of lesions within 2 months. Discontinuation of low-dose naltrexone resulted in flaring of symptoms, which cleared within 2 to 3 days on rechallenge with low-dose naltrexone. We present herein 3 cases of patients with severe Hailey-Hailey disease treated with low-dose naltrexone who achieved clinical resolution of symptoms. The success of these cases suggests low-dose naltrexone as a novel therapy for Hailey-Hailey disease. The possible mechanism may involve low-dose naltrexone influencing opioid or toll-like receptor signaling to improve calcium mobilization and improve keratinocyte differentiation and wound healing. Future studies are needed to clarify the mechanism and to define the role of low-dose naltrexone for treatment of Hailey-Hailey disease.

  13. Enhancing acupuncture by low dose naltrexone.

    PubMed

    Hesselink, Jan M Keppel; Kopsky, David J

    2011-06-01

    To find appropriate and effective treatment options for chronic pain syndromes is a challenging task. Multimodal treatment approach has been gaining acceptance for chronic pain. However, combining treatments, such as acupuncture, with rational pharmacology is still in its infancy. Acupuncture influences the opioid and cannabinoid system through releasing endogenous receptor ligands. Low dose naltrexone also acts on both these systems, and upregulates the opioid and cannabinoid receptors. The authors hypothesise that low dose naltrexone could enhance the pain-relieving effect of acupuncture.

  14. Novel Treatment Using Low-Dose Naltrexone for Lichen Planopilaris.

    PubMed

    Strazzulla, Lauren C; Avila, Lorena; Lo Sicco, Kristen; Shapiro, Jerry

    2017-11-01

    Lichen planopilaris (LPP) is a variant of lichen planus that affects the scalp causing scarring hair loss. Patients also frequently experience symptoms of scalp itch, pain, and burning. To date, there are no long-term remittive nor curative therapies available. Low-dose naltrexone has anti-inflammatory properties and has recently been described in the context of treating autoimmune conditions. This retrospective medical record review describes four LPP patients treated with low-dose (3 milligrams per day) naltrexone. This medication provided benefit in these four patients including reduction in symptoms of pruritus, clinical evidence of inflammation of the scalp, and disease progression. All patients tolerated naltrexone without adverse effects. This is the first case series demonstrating the beneficial effects of low-dose naltrexone for patients with LPP. This medication was well-tolerated by the patients and is cost-effective.

    J Drugs Dermatol. 2017;16(11):1140-1142.

    .

  15. [Low dose naltrexone in the treatment of dissociative symptoms].

    PubMed

    Pape, W; Wöller, W

    2015-03-01

    Following the hypothesis that blocking opioid receptors leads to a decline in opiate-modulated dissociative phenomena, experiences with naltrexone as medication for dissociative symptoms have been gained since 1999 (mainly in doses of 25-100 mg/day). In this study patients with severe trauma-related and dissociative disorders were treated with naltrexone in doses of 2-6 mg/day (0.06 mg/kg body weight). The low dose treatment with naltrexone proved to be effective whereby 11 out of 15 patients reported immediate positive effects and 7 described a lasting helpful effect. The majority of patients who felt positive effects reported a clearer perception of both their surroundings and their inner life. Assessment of reality and dealing with it improved as did the perception of their own body and affects as well as self-regulation. The treatment was very low in side effects. Treatment with low-dose naltrexone may be a helpful element in the treatment of patients with complex posttraumatic stress disorder. However, it has to be realized that the decrease of dissociation may lead patients to a not yet resolvable challenge, in as much as dissociation had previously been a necessary mechanism of self-protection.

  16. Low Dose Naltrexone in the Treatment of Fibromyalgia.

    PubMed

    Metyas, Samy K; Yeter, Karen; Solyman, John; Arkfeld, Daniel

    2017-03-21

    Fibromyalgia is a chronic pain disorder characterized by diffuse musculoskeletal pain, fatigue, sleep disturbance and cognitive impairment. A significant number of fibromyalgia patients do not respond adequately to the current drugs (pregabalin, milnacipran, duloxetine) approved for fibromyalgia treatment by the Food and Drug Administration (FDA). Thus, there is still a need for adjunctive therapies. Naltrexone is an opioid receptor antagonist used to treat alcohol and opioid dependence. It is hypothesized that low dose naltrexone causes transient blockade of opioid receptors centrally resulting in a rebound of endorphin function which may attenuate pain in fibromyalgia. Treatment with low dose naltrexone may be an effective, highly tolerable and inexpensive treatment for fibromyalgia. Further controlled trials are needed. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  17. Fibromyalgia symptoms are reduced by low-dose naltrexone: a pilot study.

    PubMed

    Younger, Jarred; Mackey, Sean

    2009-01-01

    Fibromyalgia is a chronic pain disorder that is characterized by diffuse musculoskeletal pain and sensitivity to mechanical stimulation. In this pilot clinical trial, we tested the effectiveness of low-dose naltrexone in treating the symptoms of fibromyalgia. Participants completed a single-blind, crossover trial with the following time line: baseline (2 weeks), placebo (2 weeks), drug (8 weeks), and washout (2 weeks). Ten women meeting criteria for fibromyalgia and not taking an opioid medication. Naltrexone, in addition to antagonizing opioid receptors on neurons, also inhibits microglia activity in the central nervous system. At low doses (4.5 mg), naltrexone may inhibit the activity of microglia and reverse central and peripheral inflammation. Participants completed reports of symptom severity everyday, using a handheld computer. In addition, participants visited the lab every 2 weeks for tests of mechanical, heat, and cold pain sensitivity. Low-dose naltrexone reduced fibromyalgia symptoms in the entire cohort, with a greater than 30% reduction of symptoms over placebo. In addition, laboratory visits showed that mechanical and heat pain thresholds were improved by the drug. Side effects (including insomnia and vivid dreams) were rare, and described as minor and transient. Baseline erythrocyte sedimentation rate predicted over 80% of the variance in drug response. Individuals with higher sedimentation rates (indicating general inflammatory processes) had the greatest reduction of symptoms in response to low-dose naltrexone. We conclude that low-dose naltrexone may be an effective, highly tolerable, and inexpensive treatment for fibromyalgia.

  18. Low doses of cyclic AMP-phosphodiesterase inhibitors rapidly evoke opioid receptor-mediated thermal hyperalgesia in naïve mice which is converted to prominent analgesia by cotreatment with ultra-low-dose naltrexone.

    PubMed

    Crain, Stanley M; Shen, Ke-Fei

    2008-09-22

    Systemic (s.c.) injection in naïve mice of cyclic AMP-phosphodiesterase (cAMP-PDE) inhibitors, e.g. 3-isobutyl-1-methylxanthine [(IBMX) or caffeine, 10 mg/kg] or the more specific cAMP-PDE inhibitor, rolipram (1 mug/kg), rapidly evokes thermal hyperalgesia (lasting >5 h). These effects appear to be mediated by enhanced excitatory opioid receptor signaling, as occurs during withdrawal in opioid-dependent mice. Cotreatment of these mice with ultra-low-dose naltrexone (NTX, 0.1 ng/kg-1 pg/kg, s.c.) results in prominent opioid analgesia (lasting >4 h) even when the dose of rolipram is reduced to 1 pg/kg. Cotreatment of these cAMP-PDE inhibitors in naïve mice with an ultra-low-dose (0.1 ng/kg) of the kappa-opioid receptor antagonist, nor-binaltorphimine (nor-BNI) or the mu-opioid receptor antagonist, beta-funaltrexamine (beta-FNA) also results in opioid analgesia. These excitatory effects of cAMP-PDE inhibitors in naïve mice may be mediated by enhanced release of small amounts of endogenous bimodally-acting (excitatory/inhibitory) opioid agonists by neurons in nociceptive networks. Ultra-low-dose NTX, nor-BNI or beta-FNA selectively antagonizes high-efficacy excitatory (hyperalgesic) Gs-coupled opioid receptor-mediated signaling in naïve mice and results in rapid conversion to inhibitory (analgesic) Gi/Go-coupled opioid receptor-mediated signaling which normally requires activation by much higher doses of opioid agonists. Cotreatment with a low subanalgesic dose of kelatorphan, an inhibitor of multiple endogenous opioid peptide-degrading enzymes, stabilizes endogenous opioid agonists released by cAMP-PDE inhibitors, resulting in conversion of the hyperalgesia to analgesia without requiring selective blockade of excitatory opioid receptor signaling. The present study provides a novel pharmacologic paradigm that may facilitate development of valuable non-narcotic clinical analgesics utilizing cotreatment with ultra-low-dose rolipram plus ultra-low-dose NTX or related

  19. Low dose Naltrexone for induction of remission in inflammatory bowel disease patients.

    PubMed

    Lie, Mitchell R K L; van der Giessen, Janine; Fuhler, Gwenny M; de Lima, Alison; Peppelenbosch, Maikel P; van der Ent, Cokkie; van der Woude, C Janneke

    2018-03-09

    Around 30% of patients with inflammatory bowel disease (IBD) are refractory to current IBD drugs or relapse over time. Novel treatments are called for, and low dose Naltrexone (LDN) may provide a safe, easily accessible alternative treatment option for these patients. We investigated the potential of LDN to induce clinical response in therapy refractory IBD patients, and investigated its direct effects on epithelial barrier function. Patients not in remission and not responding to conventional therapy were offered to initiate LDN as a concomitant treatment. In total 47 IBD patients prescribed LDN were followed prospectively for 12 weeks. Where available, endoscopic remission data, serum and biopsies were collected. Further the effect of Naltrexone on wound healing (scratch assay), cytokine production and endoplasmic reticulum (ER) stress (GRP78 and CHOP western blot analysis, immunohistochemistry) were investigated in HCT116 and CACO2 intestinal epithelial cells, human IBD intestinal organoids and patient samples. Low dose Naltrexone induced clinical improvement in 74.5%, and remission in 25.5% of patients. Naltrexone improved wound healing and reduced ER stress induced by Tunicamycin, lipopolysaccharide or bacteria in epithelial barriers. Inflamed mucosa from IBD patients showed high ER stress levels, which was reduced in patients treated with LDN. Cytokine levels in neither epithelial cells nor serum from IBD patients were affected. Naltrexone directly improves epithelial barrier function by improving wound healing and reducing mucosal ER stress levels. Low dose Naltrexone treatment is effective and safe, and could be considered for the treatment of therapy refractory IBD patients.

  20. Low-Dose Naltrexone: A New Therapy Option for Complex Regional Pain Syndrome Type I Patients.

    PubMed

    Sturn, Kayla M; Collin, Michael

    2016-01-01

    Naltrexone (an opioid antagonist) has long been used in patients overcoming alcohol and opioid dependency. However, at doses one-tenth of those commonly prescribed for the above conditions, an unexpected effect occurs that aids in alleviating pain. Although there are currently no randomized clinical trials supporting the use of low-dose naltrexone, we present a case study describing the impact of compounding low-dose naltrexone that has dramatically improved the patient's pain symptoms which were refractory to other treatments. Copyright© by International Journal of Pharmaceutical Compounding, Inc.

  1. Low dose naltrexone administration in morphine dependent rats attenuates withdrawal-induced norepinephrine efflux in forebrain.

    PubMed

    Van Bockstaele, Elisabeth J; Qian, Yaping; Sterling, Robert C; Page, Michelle E

    2008-05-15

    The administration of low dose opioid antagonists has been explored as a potential means of detoxification in opiate dependence. Previous results from our laboratory have shown that concurrent administration of low dose naltrexone in the drinking water of rats implanted with subcutaneous morphine pellets attenuates behavioral and biochemical signs of withdrawal in brainstem noradrenergic nuclei. Noradrenergic projections originating from the nucleus tractus solitarius (NTS) and the locus coeruleus (LC) have previously been shown to be important neural substrates involved in the somatic expression of opiate withdrawal. The hypothesis that low dose naltrexone treatment attenuates noradrenergic hyperactivity typically associated with opiate withdrawal was examined in the present study by assessing norepinephrine tissue content and norepinephrine efflux using in vivo microdialysis coupled to high performance liquid chromatography (HPLC) with electrochemical detection (ED). The frontal cortex (FC), amygdala, bed nucleus of the stria terminalis (BNST) and cerebellum were analyzed for tissue content of norepinephrine following withdrawal in morphine dependent rats. Naltrexone-precipitated withdrawal elicited a significant decrease in tissue content of norepinephrine in the BNST and amygdala. This decrease was significantly attenuated in the BNST of rats that received low dose naltrexone pre-treatment compared to controls. No significant difference was observed in the other brain regions examined. In a separate group of rats, norepinephrine efflux was assessed with in vivo microdialysis in the BNST or the FC of morphine dependent rats or placebo treated rats subjected to naltrexone-precipitated withdrawal that received either naltrexone in their drinking water (5 mg/L) or unadulterated water. Following baseline dialysate collection, withdrawal was precipitated by injection of naltrexone and sample collection continued for an additional 4 h. At the end of the experiment

  2. Treatment of Complex Regional Pain Syndrome (CRPS) using low dose naltrexone (LDN).

    PubMed

    Chopra, Pradeep; Cooper, Mark S

    2013-06-01

    Complex Regional Pain Syndrome (CRPS) is a neuropathic pain syndrome, which involves glial activation and central sensitization in the central nervous system. Here, we describe positive outcomes of two CRPS patients, after they were treated with low-dose naltrexone (a glial attenuator), in combination with other CRPS therapies. Prominent CRPS symptoms remitted in these two patients, including dystonic spasms and fixed dystonia (respectively), following treatment with low-dose naltrexone (LDN). LDN, which is known to antagonize the Toll-like Receptor 4 pathway and attenuate activated microglia, was utilized in these patients after conventional CRPS pharmacotherapy failed to suppress their recalcitrant CRPS symptoms.

  3. Low-Dose Naltrexone Treatment of Familial Benign Pemphigus (Hailey-Hailey Disease).

    PubMed

    Ibrahim, Omer; Hogan, Sara R; Vij, Alok; Fernandez, Anthony P

    2017-10-01

    Familial benign pemphigus, or Hailey-Hailey disease (HHD), is a rare and debilitating genetic dermatosis characterized by chronic, recurrent vesicles, erosions, and maceration in flexural areas. Despite the reported therapeutic modalities, such as topical and systemic corticosteroids, systemic immunomodulators, topical and systemic retinoids, and laser, HHD can still be markedly difficult to control. To assess low-dose naltrexone hydrochloride in the treatment of recalcitrant HHD. In this case series, 3 patients with biopsy-proven recalcitrant HHD were evaluated in the outpatient dermatology clinic at the Cleveland Clinic. Each patient was treated with low-dose naltrexone hydrochloride at a dosage of 1.5 to 3.0 mg per day. No laboratory monitoring was necessary. Clinical response (healing of erosions, improvement in erythema, and alleviation of pain), adverse effects, and subjective quality of life were monitored throughout the treatment. The study dates were January 2016 to January 2017. Objective clinical response as assessed by the treating dermatologist, subjective quality of life as reported by the patient, and recorded adverse effects were monitored throughout the treatment at intervals of 2 to 3 months. The 3 patients included a woman in her 40s and 2 men in their 60s. Each patient exhibited at least an 80% improvement in extent of disease, with one patient demonstrating 90% clearance. All 3 patients had substantial improvement in quality of life, with one patient reporting improvement in his depression. No adverse effects were recorded. Low-dose naltrexone may represent a low-cost and low-risk alternative or adjunct in the treatment of HHD.

  4. [Low dose naltrexone for treatment of pain].

    PubMed

    Plesner, Karin Bruun; Vægter, Henrik Bjarke; Handberg, Gitte

    2015-10-09

    Recent years have seen an increasing interest in the use of low dose naltrexone (LDN) for off-label treatment of pain in diseases as fibromyalgia, multiple sclerosis and morbus Crohn. The evidence is poor, with only few randomized double-blind placebo-controlled studies. The studies currently available are reviewed in this paper. LDN could be a potentially useful drug in the future for the treatment of pain in fibromyalgia, but more studies are needed to verify that it is superior to placebo, and currently it cannot be recommended as first-line therapy.

  5. Featured Article: Serum [Met5]-enkephalin levels are reduced in multiple sclerosis and restored by low-dose naltrexone.

    PubMed

    Ludwig, Michael D; Zagon, Ian S; McLaughlin, Patricia J

    2017-09-01

    Low-dose naltrexone is a widely used off-label therapeutic prescribed for a variety of immune-related disorders. The mechanism underlying low-dose naltrexone's efficacy for fatigue, Crohn's disease, fibromyalgia, and multiple sclerosis is, in part, intermittent blockade of opioid receptors followed by upregulation of endogenous opioids. Short, intermittent blockade by naltrexone specifically blocks the opioid growth factor receptor resulting in biofeedback events that increase production of the endogenous opioid growth factor (OGF) (chemically termed [Met 5 ]-enkephalin) facilitating interactions between opioid growth factor and opioid growth factor receptor that ultimately, result in inhibited cell proliferation. Preclinical studies have reported that enkephalin levels are deficient in animal models of experimental autoimmune encephalomyelitis, a mouse model of multiple sclerosis. Our hypothesis is that serum enkephalin levels are diminished in humans with multiple sclerosis and experimental autoimmune encephalomyelitis mice, and that change in serum opioid growth factor levels may serve as a reasonable candidate biomarker for the onset of experimental autoimmune encephalomyelitis and response to therapy. To address this, we designed a two-part study to measure endogenous opioids in multiple sclerosis patients, and to investigate the temporal pattern of decline in serum enkephalin concentrations in mice with chronic progressive experimental autoimmune encephalomyelitis and treated with low-dose naltrexone. For comparison, we investigated whether low-dose naltrexone exposure in normal mice also resulted in altered enkephalin levels. In both animal models, we monitored tactile and heat sensitivity, as well as differential white blood cell counts as indicators of inflammation. Serum [Met 5 ]-enkephalin levels were lower in humans with multiple sclerosis relative to non-multiple sclerosis patients, and low-dose naltrexone restored their levels. In experimental

  6. Extended release naltrexone injection is performed in the majority of opioid dependent patients receiving outpatient induction: a very low dose naltrexone and buprenorphine open label trial.

    PubMed

    Mannelli, Paolo; Wu, Li-Tzy; Peindl, Kathleen S; Swartz, Marvin S; Woody, George E

    2014-05-01

    The approval of extended release injectable naltrexone (XR-NTX; Vivitrol(®)) has introduced a new option for treating opioid addiction, but studies are needed to identify its place within the spectrum of available therapies. The absence of physiological opioid dependence is a necessary and challenging first step for starting XR-NTX. Outpatient detoxification gives poor results and inpatient detoxification is either unavailable or too brief for the physiological effects of opioids to resolve. Here we present findings from an open label study that tested whether the transition from opioid addiction to XR-NTX can be safely and effectively performed in an outpatient setting using very low dose naltrexone and buprenorphine. Twenty treatment seeking opioid addicted individuals were given increasing doses of naltrexone starting at 0.25mg with decreasing doses of buprenorphine starting at 4 mg during a 7-day outpatient XR-NTX induction procedure. Withdrawal discomfort, craving, drug use, and adverse events were assessed daily until the XR-NTX injection, then weekly over the next month. Fourteen of the 20 participants received XR-NTX and 13 completed weekly assessments. Withdrawal, craving, and opioid or other drug use were significantly lower during induction and after XR-NTX administration compared with baseline, and no serious adverse events were recorded. Outpatient transition to XR-NTX combining upward titration of very low dose naltrexone with downward titration of low dose buprenorphine was safe, well tolerated, and completed by most participants. Further studies with larger numbers of subjects are needed to see if this approach is useful for naltrexone induction. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  7. Low-dose naltrexone for the treatment of fibromyalgia: findings of a small, randomized, double-blind, placebo-controlled, counterbalanced, crossover trial assessing daily pain levels.

    PubMed

    Younger, Jarred; Noor, Noorulain; McCue, Rebecca; Mackey, Sean

    2013-02-01

    To determine whether low dosages (4.5 mg/day) of naltrexone reduce fibromyalgia severity as compared with the nonspecific effects of placebo. In this replication and extension study of a previous clinical trial, we tested the impact of low-dose naltrexone on daily self-reported pain. Secondary outcomes included general satisfaction with life, positive mood, sleep quality, and fatigue. Thirty-one women with fibromyalgia participated in the randomized, double-blind, placebo-controlled, counterbalanced, crossover study. During the active drug phase, participants received 4.5 mg of oral naltrexone daily. An intensive longitudinal design was used to measure daily levels of pain. When contrasting the condition end points, we observed a significantly greater reduction of baseline pain in those taking low-dose naltrexone than in those taking placebo (28.8% reduction versus 18.0% reduction; P = 0.016). Low-dose naltrexone was also associated with improved general satisfaction with life (P = 0.045) and with improved mood (P = 0.039), but not improved fatigue or sleep. Thirty-two percent of participants met the criteria for response (defined as a significant reduction in pain plus a significant reduction in either fatigue or sleep problems) during low-dose naltrexone therapy, as contrasted with an 11% response rate during placebo therapy (P = 0.05). Low-dose naltrexone was rated equally tolerable as placebo, and no serious side effects were reported. The preliminary evidence continues to show that low-dose naltrexone has a specific and clinically beneficial impact on fibromyalgia pain. The medication is widely available, inexpensive, safe, and well-tolerated. Parallel-group randomized controlled trials are needed to fully determine the efficacy of the medication. Copyright © 2013 by the American College of Rheumatology.

  8. The Safety and Efficacy of Low-Dose Naltrexone in the Management of Chronic Pain and Inflammation in Multiple Sclerosis, Fibromyalgia, Crohn's Disease, and Other Chronic Pain Disorders.

    PubMed

    Patten, Denise K; Schultz, Bob G; Berlau, Daniel J

    2018-03-01

    Chronic inflammatory diseases are complex to treat and have an impact on a large number of patients. Due to the difficulty of treating these diseases and the great impact on quality of life, patients often seek off-label, complimentary, or alternative medicines to gain relief from symptoms. Low-dose naltrexone has been used off-label for treatment of pain and inflammation in multiple sclerosis, Crohn's disease, fibromyalgia, and other diseases. Naltrexone is a mu-opioid receptor antagonist indicated by the U.S. Food and Drug Administration for opioid and alcohol dependence. It is hypothesized that lower than standard doses of naltrexone inhibit cellular proliferation of T and B cells and block Toll-like receptor 4, resulting in an analgesic and antiinflammatory effect. It is the purpose of this review to examine the evidence of the safety, tolerability, and efficacy of low-dose naltrexone for use in chronic pain and inflammatory conditions. Currently, evidence supports the safety and tolerability of low-dose naltrexone in multiple sclerosis, fibromyalgia, and Crohn's disease. Fewer studies support the efficacy of low-dose naltrexone, with most of these focusing on subjective measures such as quality of life or self-reported pain. These studies do demonstrate that low-dose naltrexone has subjective benefits over placebo, but evidence for more objective measures is limited. However, further randomized controlled trials are needed to determine the efficacy of low-dose naltrexone due to insufficient evidence supporting its use in these disease states. This review provides practitioners with the extent of low-dose naltrexone evidence so that they can be cognizant of situations where it may not be the most appropriate therapy. © 2018 Pharmacotherapy Publications, Inc.

  9. Long-term treatment with low dose naltrexone maintains stable health in patients with multiple sclerosis.

    PubMed

    Ludwig, Michael D; Turel, Anthony P; Zagon, Ian S; McLaughlin, Patricia J

    2016-01-01

    A retrospective study was conducted on patients at Penn State Hershey Medical Center diagnosed with relapsing-remitting multiple sclerosis between 2006 and 2015. Laboratory and clinical data collected over this 10-year period were reviewed. Two cohorts of patients were established based on their relapsing-remitting multiple sclerosis therapy at the time of their first visit to Penn State. One group of patients ( n  = 23) was initially prescribed low dose naltrexone at the time first seen at Hershey. This group was offered low dose naltrexone because of symptoms of fatigue or refusal to take an available disease-modifying therapy. The second group of patients ( n  = 31) was treated with the glatiramer acetate (Copaxone) and offered low dose naltrexone as an adjunct therapy to their disease-modifying therapy. Patient data from visits after 1-50 months post-diagnosis were evaluated in a retrospective manner. Data obtained from patient charts included clinical laboratory values from standard blood tests, timed 25-foot walking trials, and changes in magnetic resonance imaging reports. Statistical analyses between the groups and for each patient over time indicated no significant differences in clinical laboratory values, timed walking, or changes in magnetic resonance imaging. These data suggest that the apparently non-toxic, inexpensive, biotherapeutic is safe and if taken alone did not result in an exacerbation of disease symptoms.

  10. Functional modulation on macrophage by low dose naltrexone (LDN).

    PubMed

    Yi, Zhe; Guo, Shengnan; Hu, Xu; Wang, Xiaonan; Zhang, Xiaoqing; Griffin, Noreen; Shan, Fengping

    2016-10-01

    Previously it was confirmed that naltrexone, a non-peptide δ-opioid receptor selective antagonist is mainly used for alcoholic dependence and opioid addiction treatment. However, there is increasing data on immune regulation of low dose naltrexone (LDN). The aim of this work was to explore the effect of LDN on the phenotype and function of macrophage. The changes of macrophage after treatment with LDN were examined using flow cytometry (FCM); FITC-dextran phagocytosis and enzyme-linked immunosorbent assay (ELISA). We have found that LDN enhances function of macrophage as confirmed by up-regulating MHC II molecule and CD64 on macrophage while down-regulating CD206 expression. Furthermore the productions of TNF-α, IL-6, IL-1β, increased significantly. Macrophages in LDN treated group performed the enhanced phagocytosis. Therefore it is concluded that LDN could promote function of macrophage and this work has provided concrete data of impact on immune system by LDN. Especially the data would support interaction between CD4+T cell and macrophage in AIDS treatment with LDN in Africa (LDN has already been approved in Nigeria for the use in AIDS treatment). Copyright © 2016. Published by Elsevier B.V.

  11. The combination very low-dose naltrexone-clonidine in the management of opioid withdrawal.

    PubMed

    Mannelli, Paolo; Peindl, Kathleen; Wu, Li-Tzy; Patkar, Ashwin A; Gorelick, David A

    2012-05-01

    The management of withdrawal absorbs substantial clinical efforts in opioid dependence (OD). The real challenge lies in improving current pharmacotherapies. Although widely used, clonidine causes problematic adverse effects and does not alleviate important symptoms of opioid withdrawal, alone or in combination with the opioid antagonist naltrexone. Very low-dose naltrexone (VLNTX) has been shown to attenuate withdrawal intensity and noradrenaline release following opioid agonist taper, suggesting a combination with clonidine may result in improved safety and efficacy. We investigated the effects of a VLNTX-clonidine combination in a secondary analysis of data from a double-blind, randomized opioid detoxification trial. Withdrawal symptoms and treatment completion were compared following VLNTX (.125 or .25 mg/day) and clonidine (.1-.2 mg q6h) in 127 individuals with OD undergoing 6-day methadone inpatient taper at a community program. VLNTX was more effective than placebo or clonidine in reducing symptoms and signs of withdrawal. The use of VLNTX in combination with clonidine was associated with attenuated subjective withdrawal compared with each medication alone, favoring detoxification completion in comparison with clonidine or naltrexone placebo. VLNTX/clonidine was effective in reducing symptoms that are both undertreated and well controlled with clonidine treatment and was not associated with significant adverse events compared with other treatments. Preliminary results elucidate neurobiological mechanisms of OD and support the utility of controlled studies on a novel VLNTX + low-dose clonidine combination for the management of opioid withdrawal.

  12. The use of low-dose naltrexone (LDN) as a novel anti-inflammatory treatment for chronic pain.

    PubMed

    Younger, Jarred; Parkitny, Luke; McLain, David

    2014-04-01

    Low-dose naltrexone (LDN) has been demonstrated to reduce symptom severity in conditions such as fibromyalgia, Crohn's disease, multiple sclerosis, and complex regional pain syndrome. We review the evidence that LDN may operate as a novel anti-inflammatory agent in the central nervous system, via action on microglial cells. These effects may be unique to low dosages of naltrexone and appear to be entirely independent from naltrexone's better-known activity on opioid receptors. As a daily oral therapy, LDN is inexpensive and well-tolerated. Despite initial promise of efficacy, the use of LDN for chronic disorders is still highly experimental. Published trials have low sample sizes, and few replications have been performed. We cover the typical usage of LDN in clinical trials, caveats to using the medication, and recommendations for future research and clinical work. LDN may represent one of the first glial cell modulators to be used for the management of chronic pain disorders.

  13. Potentiation of low dose ketamine effects by naltrexone: potential implications for the pharmacotherapy of alcoholism.

    PubMed

    Krystal, John H; Madonick, Steven; Perry, Edward; Gueorguieva, Ralitza; Brush, Laura; Wray, Yola; Belger, Aysenil; D'Souza, Deepak Cyril

    2006-08-01

    The interplay of opiate and NMDA glutamate receptors may contribute to psychosis, cognitive function, alcoholism, and substance dependence. Ketamine and ethanol block the NMDA glutamate receptor. The purpose of this randomized double-blind, placebo-controlled human laboratory study was to evaluate whether the interactive effects of drugs acting at opiate and NMDA glutamate receptors might partially explain the efficacy of naltrexone for the treatment of alcoholism, that is, whether naltrexone 25 mg pretreatment would modulate ketamine effects in healthy human subjects. Two groups of healthy subjects were studied. An initial group (n=31) received a perception-altering subanesthetic dose of ketamine (bolus of 0.23 mg/kg over 1 min followed by a 60-min infusion of 0.58 mg/kg or saline bolus and infusion). A second group (n=24) completed the same testing procedures, but received a subperceptual ketamine dose (bolus 0.081 mg/kg over 10 min followed by an infusion of 0.4 mg/kg/h). Ketamine produced positive symptoms, negative symptoms, emotional discomfort, and cognitive effects as measured by the Positive and Negative Syndrome Scale (PANSS) in a dose-related fashion. The lower ketamine dose produced subjective effects similar to two standard ethanol drinks, whereas the higher ketamine dose produced effects similar to five standard drinks. Although naltrexone produced no significant behavioral effects, it significantly magnified the increase in the total PANSS score produced by the lower subperceptual dose of ketamine, but not the higher perception-altering dose of ketamine. These data suggest that the interplay of opiate receptor antagonism and NMDA receptor antagonism may be relevant to the protective effects of naltrexone on alcohol consumption via potentiation of dysphoric effects associated with the NMDA receptor antagonist effects of ethanol. However, these data suggest that at levels of NMDA receptor antagonism associated with heavy drinking, this protective

  14. Low-dose naltrexone for disease prevention and quality of life.

    PubMed

    Brown, Norman; Panksepp, Jaak

    2009-03-01

    The use of low-dose naltrexone (LDN) for the treatment and prophylaxis of various bodily disorders is discussed. Accumulating evidence suggests that LDN can promote health supporting immune-modulation which may reduce various oncogenic and inflammatory autoimmune processes. Since LDN can upregulate endogenous opioid activity, it may also have a role in promoting stress resilience, exercise, social bonding, and emotional well-being, as well as amelioration of psychiatric problems such a autism and depression. It is proposed that LDN can be used effectively as a buffer for a large variety of bodily and mental ailments through its ability to beneficially modulate both the immune system and the brain neurochemistries that regulate positive affect.

  15. Elevated mu-opioid receptor expression in the nucleus of the solitary tract accompanies attenuated withdrawal signs after chronic low dose naltrexone in opiate-dependent rats.

    PubMed

    Van Bockstaele, E J; Rudoy, C; Mannelli, P; Oropeza, V; Qian, Y

    2006-02-15

    We previously described a decrease in withdrawal behaviors in opiate-dependent rats that were chronically treated with very low doses of naltrexone in their drinking water. Attenuated expression of withdrawal behaviors correlated with decreased c-Fos expression and intracellular signal transduction elements [protein kinase A regulatory subunit II (PKA) and phosphorylated cAMP response element binding protein (pCREB)] in brainstem noradrenergic nuclei. In this study, to determine whether similar cellular changes occurred in forebrain nuclei associated with drug reward, expressions of PKA and pCREB were analyzed in the ventral tegmental area, frontal cortex, striatum, and amygdala of opiate-treated rats that received low doses of naltrexone in their drinking water. No significant difference in PKA or pCREB was detected in these regions following drug treatment. To examine further the cellular mechanisms in noradrenergic nuclei that could underlie attenuated withdrawal behaviors following low dose naltrexone administration, the nucleus of the solitary tract (NTS) and locus coeruleus (LC) were examined for opioid receptor (OR) protein expression. Results showed a significant increase in muOR expression in the NTS of morphine-dependent rats that received low doses of naltrexone in their drinking water, and increases in muOR expression were also found to be dose dependent. Protein expression of muOR in the LC and deltaOR in either brain region remained unchanged. In conclusion, our previously reported decreases in c-Fos and PKA expression in the NTS following pretreatment with low doses of naltrexone may be partially explained by a greater inhibition of NTS neurons resulting from increased muOR expression in this region.

  16. The efficacy of a low dose combination of topiramate and naltrexone on ethanol reinforcement and consumption in rat models.

    PubMed

    Moore, Catherine F; Protzuk, Omar A; Johnson, Bankole A; Lynch, Wendy J

    2014-01-01

    Combined medication approaches, by targeting multiple neurotransmitter systems involved in alcohol use disorders (AUDs), may be more efficacious than single-medication approaches. We examined, in animal models of consumption and reinforcement, the combined effects of naltrexone (an opioid antagonist) and topiramate (a GABA/glutamate modulator), two medications that have shown promise for treating AUDs, hypothesizing that their combination would be more efficacious than either alone. The effects of naltrexone and topiramate on ethanol consumption were examined in alcohol preferring (P) rats (N=10) and in rats from their background strain (Wistar, N=9) using conditions that induce high levels of consumption (24-h, 3-bottle, free-choice procedure). Low doses of each medication (1mg/kg, naltrexone; 10mg/kg, topiramate) were selected in an attempt to maximize their combined efficacy while minimizing potential side-effects. Their effects on ethanol reinforcement were assessed under a progressive-ratio schedule in additional groups of (N=22) P rats. A moderate dose of topiramate (20mg/kg) was also included to verify topiramate's efficacy on its own. In P rats, but not in Wistar rats, the combination effectively and persistently reduced consumption; whereas, neither dose alone was effective. The combination and naltrexone alone were equally effective at reducing ethanol reinforcement; however, with the combination, but not naltrexone alone, this effect was selective for ethanol. All treatments produced a similar decrease in home-cage food consumption. The 20mg/kg dose of topiramate also effectively reduced ethanol consumption and reinforcement. With greater efficacy and fewer side-effects, the combination shows promise as a treatment for AUDs. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. The efficacy of a low dose combination of topiramate and naltrexone on ethanol reinforcement and consumption in rat models

    PubMed Central

    Moore, Catherine F; Protzuk, Omar A; Johnson, Bankole A; Lynch, Wendy J

    2013-01-01

    Rationale Combined medication approaches, by targeting multiple neurotransmitter systems involved in alcohol use disorders (AUDs), may be more efficacious than single-medication approaches. Objectives We examined, in animals models of consumption and reinforcement, the combined effects of naltrexone (an opioid antagonist) and topiramate (a GABA/glutamate modulator), two medications that have shown promise for treating AUDs, hypothesizing that their combination would be more efficacious than either alone. Methods The effects of naltrexone and topiramate on ethanol consumption were examined in alcohol preferring (P) rats (N=10) and in rats from their background strain (Wistar, N=9) using conditions that induce high levels of consumption (24-hr, 3-bottle, free-choice procedure). Low doses of each medication (1 mg/kg, naltrexone; 10 mg/kg, topiramate) were selected in an attempt to maximize their combined efficacy while minimizing potential side-effects. Their effects on ethanol reinforcement were assessed under a progressive-ratio schedule in additional groups of (N=22) P rats. A moderate dose of topiramate (20 mg/kg) was also included to verify topiramate’s efficacy on its own. Results In P rats, but not Wistar rats, the combination effectively and persistently reduced consumption; whereas, neither dose alone was effective. The combination and naltrexone alone were equally effective at reducing ethanol reinforcement; however, with the combination, but not naltrexone alone, this effect was selective for ethanol. All treatments produced a similar decrease in home-cage food consumption. The 20 mg/kg dose of topiramate also effectively reduced ethanol consumption and reinforcement. Conclusions With greater efficacy and fewer side-effects, the combination shows promise as a treatment for AUDs. PMID:24252444

  18. Evaluation of therapeutic effect of low dose naltrexone in experimentally-induced Crohn's disease in rats.

    PubMed

    Tawfik, Dina Ibrahim; Osman, Afaf Sayed; Tolba, Hedayat Mahmoud; Khattab, Aida; Abdel-Salam, Lubna O; Kamel, Mahmoud M

    2016-10-01

    Crohn's disease is a relapsing inflammatory condition afflicting the digestive tract. Drugs used for treatment of Crohn's disease may be associated with serious side effects. Endogenous opioid peptides modulate inflammatory cytokine production. Opioid antagonists have been shown to play a role in healing and repair of tissues. This work was designed to detect the possible beneficial effects of opioid antagonist naltrexone in indomethacin-induced Crohn's disease in rats. Enteritis was induced in male albino rats by two subcutaneous injection of indomethacin in a dose of 7.5mg/kg 24h apart started on day one. Salfasalazine, naltrexone and their combination were administered orally from day one of induction of enteritis to day 10. Disease activity index, serum levels of C-reactive protein and tumor necrosis factor-α, macroscopic and microscopic pathological scores and in vitro motility studies were evaluated. Induction of enteritis resulted in significant increase of disease activity index, significant elevation of serum levels of C-reactive protein and tumor necrosis factor-α, significant deterioration of pathological scores and significant increase in the mean contractility response of the isolated ileal segments compared with normal untreated rats. Treatment with sulfasalazine, low dose of natrexone or their combination resulted in significant improvement of all measured parameters compared with enteritis group. The current finding could provide new interesting opportunity for developing new therapeutic approaches for treatment of Crohn's disease. Use of naltrexone, especially in small dose, has little side effects making it of interest for treatment of Crohn's disease. Also, it provides the possibility of reduced doses of other drugs if it is used as combined therapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. High-dose naltrexone therapy for cocaine-alcohol dependence.

    PubMed

    Schmitz, Joy M; Lindsay, Jan A; Green, Charles E; Herin, David V; Stotts, Angela L; Moeller, F Gerard

    2009-01-01

    This randomized, double-blind, placebo-controlled study compared the effects of high-dose (100 mg/d) naltrexone versus placebo in a sample of 87 randomized subjects with both cocaine and alcohol dependence. Medication conditions were crossed with two behavioral therapy platforms that examined whether adding contingency management (CM) that targeted cocaine abstinence would enhance naltrexone effects compared to cognitive behavioral therapy (CBT) without CM. Primary outcome measures for cocaine (urine screens) and alcohol use (timeline followback) were collected thrice-weekly during 12 weeks of treatment. Retention in treatment and medication compliance rates were low. Rates of cocaine use and drinks per day did not differ between treatment groups; however naltrexone did reduce frequency of heavy drinking days, as did CBT without CM. Notably, adding CM to CBT did not enhance treatment outcomes. These weak findings suggest that pharmacological and behavioral interventions that have shown efficacy in the treatment of a single drug dependence disorder may not provide the coverage needed when targeting dual drug dependence.

  20. Low-dose naltrexone augmentation of nicotine replacement for smoking cessation with reduced weight gain: a randomized trial.

    PubMed

    Toll, Benjamin A; White, Marney; Wu, Ran; Meandzija, Boris; Jatlow, Peter; Makuch, Robert; O'Malley, Stephanie S

    2010-10-01

    Fear of weight gain is a significant obstacle to smoking cessation, preventing some smokers from attempting to quit. Several previous studies of naltrexone yielded promising results for minimization of post-quit weight gain. Given these encouraging findings, we endeavored to test whether minimization of weight gain might translate to better quit outcomes for a population that is particularly concerned about gaining weight upon quitting. Smokers (N=172) in this investigation were prospectively randomized to receive either 25 mg naltrexone or placebo for 27 weeks (1 week pre-, 26 weeks post-quit) for minimization of post-quit weight gain and smoking cessation. All participants received open label therapy with the nicotine patch for the first 8 weeks post-quit and behavioral counseling over the 27-week treatment. The 2 pre-specified primary outcomes were change in weight for continuously abstinent participants and biologically verified end-of-treatment 7-day point-prevalence abstinence at 26 weeks after the quit date. The difference in weight at 26 weeks post-quit between the naltrexone and placebo groups (naltrexone: 6.8 lbs ± 8.94 vs placebo: 9.7 lbs ± 9.19, p = 0.45) was not statistically different. Seven-day point-prevalence smoking abstinence rates at 26 weeks post-quit was not significantly different between the 2 groups (naltrexone: 22% vs placebo: 27%, p = 0.43). For smokers high in weight concern, the relatively small reduction in weight gain with low-dose naltrexone is not worth the potential for somewhat lower rates of smoking abstinence. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  1. Problem drinking and low-dose naltrexone-assisted opioid detoxification.

    PubMed

    Mannelli, Paolo; Peindl, Kathleen; Patkar, Ashwin A; Wu, Li-Tzy; Tharwani, Haresh M; Gorelick, David A

    2011-05-01

    The influence of alcohol use on opioid dependence is a major problem that warrants a search for more effective treatment strategies. The addition of very-low-dose naltrexone (VLNTX) to methadone taper was recently associated with reduced withdrawal intensity during detoxification. In a secondary analysis of these data, we sought to determine whether problem drinking affects detoxification outcomes and whether symptoms are influenced by VLNTX use. Opioid-dependent patients (N = 174) received naltrexone (0.125 or 0.250 mg/day) or placebo in a double-blind, randomized design during methadone-based, 6-day inpatient detoxification. Alcohol consumption was assessed at admission using the Addiction Severity Index and selfreport. Outcome measures were opioid withdrawal intensity, craving, and retention in treatment. Problem drinking-opioid dependent patients (n = 79) showed episodic heavy alcohol use and reported increased subjective opioid withdrawal intensity (p = .001), craving (p = .001), and significantly lower rate of retention in treatment (p = .02). Individuals with problem drinking and opioid dependence who were treated with VLNTX (n = 55) showed reduced withdrawal (p = .05) and a lower rate of treatment discontinuation (p = .03), resuming alcohol intake in smaller numbers the day following discharge (p = .03). Treatment effects were more pronounced on anxiety, perspiration, shakiness, nausea, stomach cramps, and craving. There were no group differences in use of adjuvant medications and no treatment-related adverse events. Heavy drinking is associated with worse opioid detoxification outcomes. The addition of VLNTX is safe and is associated with reduced withdrawal symptoms and better completion rate in these patients. Further studies should explore the use of VLNTX in detoxification and long-term treatment of combined alcohol-opioid dependence and alcohol dependence alone.

  2. Pilot trial of low-dose naltrexone and quality of life in multiple sclerosis.

    PubMed

    Cree, Bruce A C; Kornyeyeva, Elena; Goodin, Douglas S

    2010-08-01

    To evaluate the efficacy of 4.5mg nightly naltrexone on the quality of life of multiple sclerosis (MS) patients. This single-center, double-masked, placebo-controlled, crossover study evaluated the efficacy of 8 weeks of treatment with 4.5mg nightly naltrexone (low-dose naltrexone, LDN) on self-reported quality of life of MS patients. Eighty subjects with clinically definite MS were enrolled, and 60 subjects completed the trial. Ten withdrew before completing the first trial period: 8 for personal reasons, 1 for a non-MS-related adverse event, and 1 for perceived benefit. Database management errors occurred in 4 other subjects, and quality of life surveys were incomplete in 6 subjects for unknown reasons. The high rate of subject dropout and data management errors substantially reduced the trial's statistical power. LDN was well tolerated, and serious adverse events did not occur. LDN was associated with significant improvement on the following mental health quality of life measures: a 3.3-point improvement on the Mental Component Summary score of the Short Form-36 General Health Survey (p = 0.04), a 6-point improvement on the Mental Health Inventory (p < 0.01), a 1.6-point improvement on the Pain Effects Scale (p =.04), and a 2.4-point improvement on the Perceived Deficits Questionnaire (p = 0.05). LDN significantly improved mental health quality of life indices. Further studies with LDN in MS are warranted.

  3. Ultra-low dose (+)-naloxone restores the thermal threshold of morphine tolerant rats.

    PubMed

    Chou, Kuang-Yi; Tsai, Ru-Yin; Tsai, Wei-Yuan; Wu, Ching-Tang; Yeh, Chun-Chang; Cherng, Chen-Hwan; Wong, Chih-Shung

    2013-12-01

    As known, long-term morphine infusion leads to tolerance. We previously demonstrated that both co-infusion and post-administration of ultra-low dose (±)-naloxone restores the antinociceptive effect of morphine in morphine-tolerant rats. However, whether the mechanism of the action of ultra-low dose (±)-naloxone is through opioid receptors or not. Therefore, in the present study, we further investigated the effect of ultra-low dose (+)-naloxone, it does not bind to opioid receptors, on the antinociceptive effect of morphine. Male Wistar rats were implanted with one or two intrathecal (i.t.) catheters; one catheter was connected to a mini-osmotic pump, used for morphine (15 μg/h), ultra-low dose (+)-naloxone (15 pg/h), morphine plus ultra-low dose (+)-naloxone (15 pg/h) or saline (1 μl/h) infusion for 5 days. On day 5, either ultra-low dose (+)-naloxone (15 pg) or saline (5 μl) was injected via the other catheter immediately after discontinued morphine or saline infusion. Three hours later, morphine (15 μg in 5 μl saline) or saline were given intrathecally. All rats received nociceptive tail-flick test every 30 minutes for 120 minutes after morphine challenge at different temperature (45-52°C, respective). Our results showed that, both co-infusion and post-treatment of ultra-low dose (+)-naloxone with morphine preserves the antinociceptive effect of morphine. Moreover, in the post administration rats, ultra-low dose (+)-naloxone further enhances the antinociceptive effect of morphine. This study provides an evidence for ultra-low dose (+)-naloxone as a therapeutic adjuvant for patients who need long-term opioid administration for pain management. Copyright © 2013. Published by Elsevier B.V.

  4. Convolutional auto-encoder for image denoising of ultra-low-dose CT.

    PubMed

    Nishio, Mizuho; Nagashima, Chihiro; Hirabayashi, Saori; Ohnishi, Akinori; Sasaki, Kaori; Sagawa, Tomoyuki; Hamada, Masayuki; Yamashita, Tatsuo

    2017-08-01

    The purpose of this study was to validate a patch-based image denoising method for ultra-low-dose CT images. Neural network with convolutional auto-encoder and pairs of standard-dose CT and ultra-low-dose CT image patches were used for image denoising. The performance of the proposed method was measured by using a chest phantom. Standard-dose and ultra-low-dose CT images of the chest phantom were acquired. The tube currents for standard-dose and ultra-low-dose CT were 300 and 10 mA, respectively. Ultra-low-dose CT images were denoised with our proposed method using neural network, large-scale nonlocal mean, and block-matching and 3D filtering. Five radiologists and three technologists assessed the denoised ultra-low-dose CT images visually and recorded their subjective impressions of streak artifacts, noise other than streak artifacts, visualization of pulmonary vessels, and overall image quality. For the streak artifacts, noise other than streak artifacts, and visualization of pulmonary vessels, the results of our proposed method were statistically better than those of block-matching and 3D filtering (p-values < 0.05). On the other hand, the difference in the overall image quality between our proposed method and block-matching and 3D filtering was not statistically significant (p-value = 0.07272). The p-values obtained between our proposed method and large-scale nonlocal mean were all less than 0.05. Neural network with convolutional auto-encoder could be trained using pairs of standard-dose and ultra-low-dose CT image patches. According to the visual assessment by radiologists and technologists, the performance of our proposed method was superior to that of large-scale nonlocal mean and block-matching and 3D filtering.

  5. Long-Acting Injectable Naltrexone Induction: A Randomized Trial of Outpatient Opioid Detoxification With Naltrexone Versus Buprenorphine.

    PubMed

    Sullivan, Maria; Bisaga, Adam; Pavlicova, Martina; Choi, C Jean; Mishlen, Kaitlyn; Carpenter, Kenneth M; Levin, Frances R; Dakwar, Elias; Mariani, John J; Nunes, Edward V

    2017-05-01

    At present there is no established optimal approach for transitioning opioid-dependent adults to extended-release injection naltrexone (XR-naltrexone) while preventing relapse. The authors conducted a trial examining the efficacy of two methods of outpatient opioid detoxification for induction to XR-naltrexone. Participants were 150 opioid-dependent adults randomly assigned 2:1 to one of two outpatient detoxification regimens, naltrexone-assisted detoxification or buprenorphine-assisted detoxification, followed by an injection of XR-naltrexone. Naltrexone-assisted detoxification lasted 7 days and included a single day of buprenorphine followed by ascending doses of oral naltrexone along with clonidine and other adjunctive medications. Buprenorphine-assisted detoxification included a 7-day buprenorphine taper followed by a week-long delay before administration of XR-naltrexone, consistent with official prescribing information for XR-naltrexone. Participants from both groups received behavioral therapy focused on medication adherence and a second dose of XR-naltrexone. Compared with participants in the buprenorphine-assisted detoxification condition, participants assigned to naltrexone-assisted detoxification were significantly more likely to be successfully inducted to XR-naltrexone (56.1% compared with 32.7%) and to receive the second injection at week 5 (50.0% compared with 26.9%). Both models adjusted for primary type of opioid use, route of opioid administration, and morphine equivalents at baseline. These results demonstrate the safety, efficacy, and tolerability of low-dose naltrexone, in conjunction with single-day buprenorphine dosing and adjunctive nonopioid medications, for initiating adults with opioid dependence to XR-naltrexone. This strategy offers a promising alternative to the high rates of attrition and relapse currently observed with agonist tapers in both inpatient and outpatient settings.

  6. Enhanced Low Dose Rate Sensitivity at Ultra-Low Dose Rates

    NASA Technical Reports Server (NTRS)

    Chen, Dakai; Pease, Ronald; Forney, James; Carts, Martin; Phan, Anthony; Cox, Stephen; Kruckmeyer, Kriby; Burns, Sam; Albarian, Rafi; Holcombe, Bruce; hide

    2011-01-01

    We have presented results of ultra-low dose rate irradiations (< or = 10 mrad(Si)/s) for a variety of radiation hardened and commercial linear bipolar devices. We observed low dose rate enhancement factors exceeding 1.5 in several parts. The worst case of dose rate enhancement resulted in functional failures, which occurred after 10 and 60 krad(Si), for devices irradiated at 0.5 and 10 mrad(Si)/s, respectively. Devices fabricated with radiation hardened processes and designs also displayed dose rate enhancement at below 10 mrad(Si)/s. Furthermore, the data indicated that these devices have not reached the damage saturation point. Therefore the degradation will likely continue to increase with increasing total dose, and the low dose rate enhancement will further magnify. The cases presented here, in addition to previous examples, illustrate the significance and pervasiveness of low dose rate enhancement at dose rates lower than 10 mrad(Si). These results present further challenges for radiation hardness assurance of bipolar linear circuits, and raise the question of whether the current standard test dose rate is conservative enough to bound degradations due to ELDRS.

  7. Early outcomes following low dose naltrexone enhancement of opioid detoxification.

    PubMed

    Mannelli, Paolo; Patkar, Ashwin A; Peindl, Kathleen; Gottheil, Edward; Wu, Li-Tzy; Gorelick, David A

    2009-01-01

    Although withdrawal severity and treatment completion are the initial focus of opioid detoxification, post-detoxification outcome better defines effective interventions. Very low dose naltrexone (VLNTX) in addition to methadone taper was recently associated with attenuated withdrawal intensity during detoxification. We describe the results of a seven-day follow-up evaluation of 96 subjects who completed inpatient detoxification consisting of the addition of VLNTX (0.125 or 0.250 mg per day) or placebo to methadone taper in a double blind, randomized investigation. Individuals receiving VLNTX during detoxification reported reduced withdrawal and drug use during the first 24 hours after discharge. VLNTX addition was also associated with higher rates of negative drug tests for opioids and cannabis and increased engagement in outpatient treatment after one week. Further studies are needed to test the utility of this approach in easing the transition from detoxification to various follow-up treatment modalities designed to address opioid dependence.

  8. Varenicline, low dose naltrexone, and their combination for heavy-drinking smokers: human laboratory findings.

    PubMed

    Ray, Lara A; Courtney, Kelly E; Ghahremani, Dara G; Miotto, Karen; Brody, Arthur; London, Edythe D

    2014-10-01

    Heavy-drinking smokers constitute a sizeable and hard-to-treat subgroup of smokers, for whom tailored smoking cessation therapies are not yet available. The present study used a double-blind, randomized, 2 × 2 medication design, testing varenicline alone (VAR; 1 mg twice daily), low dose naltrexone alone (L-NTX; 25 mg once daily), varenicline plus naltrexone, and placebo for effects on cigarette craving and subjective response to alcohol and cigarettes in a sample (n = 130) of heavy-drinking daily smokers (≥10 cigarettes/day). All participants were tested after a 9-day titration period designed to reach a steady state on the target medication. Testing was completed at 12 h of nicotine abstinence, after consuming a standard dose of alcohol (target breath alcohol concentration = 0.06 g/dl) and after smoking the first cigarette of the day. The combination of VAR + L-NTX was superior to placebo, and at times superior to monotherapy, in attenuating cigarette craving, cigarette and alcohol "high," and in reducing ad-lib consumption of both cigarettes and alcohol during the 9-day medication titration period. These preliminary findings indicate that clinical studies of the combination of VAR + L-NTX for heavy drinkers trying to quit smoking are warranted and may ultimately improve clinical care for this sizeable and treatment-resistant subgroup of smokers.

  9. Low-dose prazosin alone and in combination with propranolol or naltrexone: effects on ethanol and sucrose seeking and self-administration in the P rat.

    PubMed

    Verplaetse, Terril L; Czachowski, Cristine L

    2015-08-01

    Evidence suggests that the noradrenergic system mediates ethanol reinforcement. However, preclinical studies suggest that noradrenergic antagonists block other oral reinforcers indicating possible unwanted secondary medication effects. This study examined combinations of low-dose prazosin with propranolol or naltrexone using a behavioral paradigm that separately assesses reinforcer seeking and self-administration. Male alcohol-preferring (P) rats (n = 20/experiment) were trained to complete a response requirement (RR) resulting in access to 1 % sucrose (n = 10) or 10 % ethanol (n = 10) for 20 min. Rats received vehicle, prazosin alone (0.125, 0.25, 0.5, and 1.0 mg/kg, intraperitoneally (IP)), or prazosin in combination with propranolol (5 mg/kg (IP); Exp. 1) or in combination with naltrexone (0.03 mg/kg, subcutaneously (SC); Exp. 2). For Exp. 1, prazosin alone effectively decreased sucrose seeking more than ethanol seeking, but decreased ethanol self-administration only. Propranolol alone effectively decreased ethanol seeking more than sucrose seeking and decreased ethanol intake only. At some dose combinations, there was a greater attenuation of ethanol and sucrose intake relative to either drug alone. For Exp. 2, prazosin alone and naltrexone alone were effective in decreasing ethanol seeking and intake only. Combination treatment was more effective than either drug alone at decreasing ethanol seeking and consumption and sucrose intake, but not sucrose seeking. Propranolol and naltrexone alone were specific to ethanol indicating that low doses of either medication may be beneficial in treating alcohol use disorders. Prazosin in combination with propranolol or naltrexone was more effective than either drug alone and also reduced sucrose-reinforced behaviors. These data suggest that the noradrenergic system is a viable target for developing treatment approaches for problem drinkers.

  10. Low-Dose Prazosin Alone and in Combination with Propranolol or Naltrexone: Effects on Ethanol- and Sucrose-Seeking and Self-Administration in the P Rat

    PubMed Central

    Verplaetse, Terril L.; Czachowski, Cristine L.

    2015-01-01

    Rationale Evidence suggests that the noradrenergic system mediates ethanol-reinforcement. However, preclinical studies suggest that noradrenergic antagonists block other oral reinforcers indicating possible unwanted secondary medication effects. Methods This study examined combinations of low-dose prazosin with propranolol or naltrexone using a behavioral paradigm that separately assesses reinforcer-seeking and self-administration. Male alcohol-preferring (P) rats (n=20/experiment) were trained to complete a response requirement (RR) resulting in access to 1% sucrose (n=10) or 10% ethanol (n=10) for 20min. Rats received vehicle, prazosin alone (0.125, 0.25, 0.5, 1.0 mg/kg; intraperitoneally (IP)) or prazosin in combination with propranolol (5 mg/kg (IP); Exp1) or in combination with naltrexone (0.03 mg/kg (subcutaneously (SC); Exp2). Results For Exp1, prazosin alone effectively decreased sucrose-seeking more than ethanol-seeking, but decreased ethanol self-administration only. Propranolol alone effectively decreased ethanol-seeking more than sucrose-seeking and decreased ethanol intake only. At some dose combinations, there was a greater attenuation of ethanol and sucrose intake relative to either drug alone. For Exp2, prazosin alone and naltrexone alone were effective in decreasing ethanol-seeking and intake only. Combination treatment was more effective than either drug alone at decreasing ethanol-seeking and consumption and sucrose intake, but not sucrose-seeking. Conclusions Propranolol and naltrexone alone were specific to ethanol indicating that low doses of either medication may be beneficial in treating alcohol use disorders. Prazosin in combination with propranolol or naltrexone was more effective than either drug alone, but also reduced sucrose-reinforced behaviors. These data suggest that the noradrenergic system is a viable target for developing treatment approaches for problem drinkers. PMID:25743758

  11. Effects of Varenicline Alone and in Combination With Low-dose Naltrexone on Alcohol-primed Smoking in Heavy-drinking Tobacco Users: A Preliminary Laboratory Study.

    PubMed

    Roberts, Walter; Shi, Julia M; Tetrault, Jeanette M; McKee, Sherry A

    Heavy-drinking tobacco users are less likely to successfully quit smoking than their moderate-drinking counterparts, even when they are prescribed smoking cessation medication. One strategy for improving treatment outcomes in this subgroup of tobacco users may be to combine medication therapies to target both alcohol and tobacco use simultaneously. Adding naltrexone to frontline smoking cessation treatments may improve treatment outcomes in this group. This double-blind, placebo-controlled human laboratory study examined the effects of varenicline (2 mg/d) and varenicline (2 mg/d), combined with a low dose of naltrexone (25 mg/d) on alcohol-primed smoking behavior in a laboratory model of smoking relapse in heavy-drinking tobacco users (n = 30). Participants attended a laboratory session and received an alcohol challenge (target breath alcohol concentration = 0.030 g/dL). They completed a smoking delay task that assessed their ability to resist smoking followed by an ad libitum smoking phase (primary outcomes). They also provided ratings of subjective drug effects and craving, and carbon monoxide levels were measured after smoking (secondary outcomes). Participants receiving varenicline monotherapy delayed smoking longer and smoked fewer cigarettes than those on placebo. Participants receiving varenicline + low-dose naltrexone did not delay smoking longer than those receiving varenicline alone. Participants in both active medication arms smoked fewer cigarettes ad libitum than those receiving placebo. Varenicline can improve smoking outcomes even after an alcohol prime, supporting its use in heavy drinkers who wish to quit smoking. Findings did not support increased efficacy of combined varenicline + low-dose naltrexone relative to varenicline monotherapy.

  12. Comparative performance analysis for computer aided lung nodule detection and segmentation on ultra-low-dose vs. standard-dose CT

    NASA Astrophysics Data System (ADS)

    Wiemker, Rafael; Rogalla, Patrik; Opfer, Roland; Ekin, Ahmet; Romano, Valentina; Bülow, Thomas

    2006-03-01

    The performance of computer aided lung nodule detection (CAD) and computer aided nodule volumetry is compared between standard-dose (70-100 mAs) and ultra-low-dose CT images (5-10 mAs). A direct quantitative performance comparison was possible, since for each patient both an ultra-low-dose and a standard-dose CT scan were acquired within the same examination session. The data sets were recorded with a multi-slice CT scanner at the Charite university hospital Berlin with 1 mm slice thickness. Our computer aided nodule detection and segmentation algorithms were deployed on both ultra-low-dose and standard-dose CT data without any dose-specific fine-tuning or preprocessing. As a reference standard 292 nodules from 20 patients were visually identified, each nodule both in ultra-low-dose and standard-dose data sets. The CAD performance was analyzed by virtue of multiple FROC curves for different lower thresholds of the nodule diameter. For nodules with a volume-equivalent diameter equal or larger than 4 mm (149 nodules pairs), we observed a detection rate of 88% at a median false positive rate of 2 per patient in standard-dose images, and 86% detection rate in ultra-low-dose images, also at 2 FPs per patient. Including even smaller nodules equal or larger than 2 mm (272 nodules pairs), we observed a detection rate of 86% in standard-dose images, and 84% detection rate in ultra-low-dose images, both at a rate of 5 FPs per patient. Moreover, we observed a correlation of 94% between the volume-equivalent nodule diameter as automatically measured on ultra-low-dose versus on standard-dose images, indicating that ultra-low-dose CT is also feasible for growth-rate assessment in follow-up examinations. The comparable performance of lung nodule CAD in ultra-low-dose and standard-dose images is of particular interest with respect to lung cancer screening of asymptomatic patients.

  13. The Effects of ELDRS at Ultra-Low Dose Rates

    NASA Technical Reports Server (NTRS)

    Chen, Dakai; Forney, James; Carts, Martin; Phan, Anthony; Cox, Stephen; Kruckmeyer, Kirby; Burns, Sam; Albarian, Rafi; Holcombe, Bruce; Little, Bradley; hide

    2010-01-01

    We present results of ultra-low dose-rate irradiations on a variety of commercial and radiation hardened bipolar circuits. We observed enhanced degradations at dose rates lower than 10 mrad(Si)/s in some devices.

  14. Effectiveness of low-dose naltrexone in the post-detoxification treatment of opioid dependence.

    PubMed

    Mannelli, Paolo; Patkar, Ashwin A; Peindl, Kathleen; Murray, Heather W; Wu, Li-Tzy; Hubbard, Robert

    2007-10-01

    The clinical use of naltrexone (NTX) in the treatment of opioid dependence has been limited because of poor compliance and inconsistent outcomes. In particular, the therapeutic benefit of extended treatment with NTX after opioid detoxification is unclear. The present study evaluated whether the augmentation with low-dose NTX during the post-detoxification treatment of opioid dependence would improve outcomes. In an open-label naturalistic design, 435 opioid-dependent patients who had completed inpatient detoxification were offered the choice of entering 1 of the 2 outpatient treatment arms: clonidine extended treatment (CET) (clonidine + psychosocial treatment), or enhanced extended treatment (EET) (oral NTX [1-10 mg/d] + CET) for 21 days. The primary outcome measure was retention in treatment. Secondary outcomes included abstinence from opioids, dropouts, and adherence to postdischarge care. One hundred sixty-two patients (37.2%) accepted EET. Subjects receiving EET stayed longer in the program (F = 64.4; P = 0.000), were less likely to drop out, used less opioids, and followed through with referral to long-term outpatient treatment in a higher number, compared with patients in the CET arm (P = 0.000 in each case). The NTX + clonidine combination was safe and well tolerated. This preliminary study indicates the potential benefit of augmentation with low-dose NTX to improve outcomes after opioid detoxification for a preferred group of patients. Randomized controlled trials are necessary to further evaluate the role of low-dose NTX in the outpatient treatment of opioid dependence.

  15. Very low dose naltrexone addition in opioid detoxification: a randomized, controlled trial.

    PubMed

    Mannelli, Paolo; Patkar, Ashwin A; Peindl, Kathi; Gorelick, David A; Wu, Li-Tzy; Gottheil, Edward

    2009-04-01

    Although current treatments for opioid detoxification are not always effective, medical detoxification remains a required step before long-term interventions. The use of opioid antagonist medications to improve detoxification has produced inconsistent results. Very low dose naltrexone (VLNTX) was recently found to reduce opioid tolerance and dependence in animal and clinical studies. We decided to evaluate safety and efficacy of VLNTX adjunct to methadone in reducing withdrawal during detoxification. In a multi-center, double-blind, randomized study at community treatment programs, where most detoxifications are performed, 174 opioid-dependent subjects received NTX 0.125 mg, 0.250 mg or placebo daily for 6 days, together with methadone in tapering doses. VLNTX-treated individuals reported attenuated withdrawal symptoms [F = 7.24 (2,170); P = 0.001] and reduced craving [F = 3.73 (2,107); P = 0.03]. Treatment effects were more pronounced at discharge and were not accompanied by a significantly higher retention rate. There were no group differences in use of adjuvant medications and no treatment-related adverse events. Further studies should explore the use of VLNTX, combined with full and partial opioid agonist medications, in detoxification and long-term treatment of opioid dependence.

  16. Naltrexone at low doses upregulates a unique gene expression not seen with normal doses: Implications for its use in cancer therapy.

    PubMed

    Liu, Wai M; Scott, Katherine A; Dennis, Jayne L; Kaminska, Elwira; Levett, Alan J; Dalgleish, Angus G

    2016-08-01

    It has been reported that lower doses of the opioid antagonist naltrexone are able to reduce tumour growth by interfering with cell signalling as well as by modifying the immune system. We have evaluated the gene expression profile of a cancer cell line after treatment with low-dose naltrexone (LDN), and assessed the effect that adapting treatment schedules with LDN may have on enhancing efficacy. LDN had a selective impact on genes involved with cell cycle regulation and immune modulation. Similarly, the pro-apoptotic genes BAD and BIK1 were increased only after LDN. Continuous treatment with LDN had little effect on growth in different cell lines; however, altering the treatment schedule to include a phase of culture in the absence of drug following an initial round of LDN treatment, resulted in enhanced cell killing. Furthermore, cells pre-treated with LDN were more sensitive to the cytotoxic effects of a number of common chemotherapy agents. For example, priming HCT116 with LDN before treatment with oxaliplatin significantly increased cell killing to 49±7.0 vs. 14±2.4% in cultures where priming was not used. Interestingly, priming with NTX before oxaliplatin resulted in just 32±1.8% cell killing. Our data support further the idea that LDN possesses anticancer activity, which can be improved by modifying the treatment schedule.

  17. Behavioural profile of exendin-4/naltrexone dose combinations in male rats during tests of palatable food consumption.

    PubMed

    Wright, F L; Rodgers, R J

    2014-09-01

    The glucagon-like peptide 1 receptor (GLP-1R) agonist exendin-4 potently suppresses food intake in animals and humans. However, little is known about the behavioural specificity of this effect either when administered alone or when co-administered with another anorectic agent. The present study characterises the effects of exendin-4, both alone and in combination with naltrexone, on behaviours displayed by male rats during tests with palatable mash. Experiment 1 examined the dose-response effects of exendin-4 (0.025-2.5 μg/kg, IP), while experiment 2 profiled the effects of low-dose combinations of the peptide (0.025 and 0.25 μg/kg) and naltrexone (0.1 mg/kg). In experiment 1, exendin-4 dose dependently suppressed food intake as well as the frequency and rate of eating. However, these effects were accompanied by dose-dependent reductions in all active behaviours and, at 2.5 μg/kg, a large increase in resting and disruption of the behavioural satiety sequence (BSS). In experiment 2, while exendin-4 (0.25 μg/kg) and naltrexone each produced a significant reduction in intake and feeding behaviour (plus an acceleration in the BSS), co-treatment failed to produce stronger effects than those seen in response to either compound alone. Similarities between the behavioural signature of exendin-4 and that previously reported for the emetic agent lithium chloride would suggest that exendin-4 anorexia is related to the aversive effects of the peptide. Furthermore, as low-dose combinations of the peptide with naltrexone failed to produce an additive/synergistic anorectic effect, this particular co-treatment strategy would not appear to have therapeutic significance.

  18. Low dose naltrexone for induction of remission in Crohn's disease.

    PubMed

    Segal, Dan; Macdonald, John K; Chande, Nilesh

    2014-02-21

    Crohn's disease is a transmural, relapsing inflammatory condition afflicting the digestive tract. Opioid signalling, long known to affect secretion and motility in the gut, has been implicated in the inflammatory cascade of Crohn's disease. Low dose naltrexone, an opioid antagonist, has garnered interest as a potential therapy. The primary objective was to evaluate the efficacy and safety of low dose naltrexone for induction of remission in Crohn's disease. A systematic search of MEDLINE, EMBASE, CENTRAL, and the Cochrane Inflammatory Bowel Disease and Functional Bowel Disorders Review Group Specialized Register was performed from inception to February 2013 to identify relevant studies. Abstracts from major gastroenterology conferences including Digestive Disease Week and United European Gastroenterology Week and reference lists from retrieved articles were also reviewed. Randomized controlled trials of low dose naltrexone (LDN) for treatment of active Crohn's disease were included. Data were analyzed on an intention-to-treat basis using Review Manager (RevMan 5.2). The primary outcome was induction of clinical remission defined by a Crohn's disease activity index (CDAI) of < 150 or a pediatric Crohn's disease activity index (PCDAI) of < 10. Secondary outcomes included clinical response (70- or 100-point decrease in CDAI from baseline), endoscopic remission or response, quality of life, and adverse events as defined by the included studies. Risk ratios (RR) and 95% confidence intervals (CI) were calculated for dichotomous outcomes. The methodological quality of included studies was evaluated using the Cochrane risk of bias tool. The overall quality of the evidence supporting the primary outcome and selected secondary outcomes was assessed using the GRADE criteria. Two studies were identified (46 participants). One study assessed the efficacy and safety of 12 weeks of LDN (4.5 mg/day) treatment compared to placebo in adult patients (N = 34). The other study assessed

  19. Low dose naltrexone for induction of remission in Crohn's disease.

    PubMed

    Parker, Claire E; Nguyen, Tran M; Segal, Dan; MacDonald, John K; Chande, Nilesh

    2018-04-01

    Crohn's disease is a transmural, relapsing inflammatory condition afflicting the digestive tract. Opioid signalling, long known to affect secretion and motility in the gut, has been implicated in the inflammatory cascade of Crohn's disease. Low dose naltrexone, an opioid antagonist, has garnered interest as a potential therapy. The primary objective was to evaluate the efficacy and safety of low dose naltrexone for induction of remission in Crohn's disease. A systematic search of MEDLINE, Embase, PubMed, CENTRAL, and the Cochrane IBD Group Specialized Register was performed from inception to 15 January 2018 to identify relevant studies. Abstracts from major gastroenterology conferences including Digestive Disease Week and United European Gastroenterology Week and reference lists from retrieved articles were also screened. Randomized controlled trials of low dose naltrexone (LDN) for treatment of active Crohn's disease were included. Data were analyzed on an intention-to-treat basis using Review Manager (RevMan 5.3.5). The primary outcome was induction of clinical remission defined by a Crohn's disease activity index (CDAI) of < 150 or a pediatric Crohn's disease activity index (PCDAI) of < 10. Secondary outcomes included clinical response (70- or 100-point decrease in CDAI from baseline), endoscopic remission or response, quality of life, and adverse events as defined by the included studies. Risk ratios (RR) and 95% confidence intervals (CI) were calculated for dichotomous outcomes. The methodological quality of included studies was evaluated using the Cochrane risk of bias tool. The overall quality of the evidence supporting the primary outcome and selected secondary outcomes was assessed using the GRADE criteria. Two studies were identified (46 participants). One study assessed the efficacy and safety of 12 weeks of LDN (4.5 mg/day) treatment compared to placebo in adult patients (N = 34). The other study assessed eight weeks of LDN (0.1 mg/kg, maximum 4.5 mg

  20. Ultra-Low-Dose Fetal CT With Model-Based Iterative Reconstruction: A Prospective Pilot Study.

    PubMed

    Imai, Rumi; Miyazaki, Osamu; Horiuchi, Tetsuya; Asano, Keisuke; Nishimura, Gen; Sago, Haruhiko; Nosaka, Shunsuke

    2017-06-01

    Prenatal diagnosis of skeletal dysplasia by means of 3D skeletal CT examination is highly accurate. However, it carries a risk of fetal exposure to radiation. Model-based iterative reconstruction (MBIR) technology can reduce radiation exposure; however, to our knowledge, the lower limit of an optimal dose is currently unknown. The objectives of this study are to establish ultra-low-dose fetal CT as a method for prenatal diagnosis of skeletal dysplasia and to evaluate the appropriate radiation dose for ultra-low-dose fetal CT. Relationships between tube current and image noise in adaptive statistical iterative reconstruction and MBIR were examined using a 32-cm CT dose index (CTDI) phantom. On the basis of the results of this examination and the recommended methods for the MBIR option and the known relationship between noise and tube current for filtered back projection, as represented by the expression SD = (milliamperes) -0.5 , the lower limit of the optimal dose in ultra-low-dose fetal CT with MBIR was set. The diagnostic power of the CT images obtained using the aforementioned scanning conditions was evaluated, and the radiation exposure associated with ultra-low-dose fetal CT was compared with that noted in previous reports. Noise increased in nearly inverse proportion to the square root of the dose in adaptive statistical iterative reconstruction and in inverse proportion to the fourth root of the dose in MBIR. Ultra-low-dose fetal CT was found to have a volume CTDI of 0.5 mGy. Prenatal diagnosis was accurately performed on the basis of ultra-low-dose fetal CT images that were obtained using this protocol. The level of fetal exposure to radiation was 0.7 mSv. The use of ultra-low-dose fetal CT with MBIR led to a substantial reduction in radiation exposure, compared with the CT imaging method currently used at our institution, but it still enabled diagnosis of skeletal dysplasia without reducing diagnostic power.

  1. Sex hormone-binding globulin and antithrombin III activity in women with oral ultra-low-dose estradiol.

    PubMed

    Matsui, Sumika; Yasui, Toshiyuki; Kasai, Kana; Keyama, Kaoru; Yoshida, Kanako; Kato, Takeshi; Uemura, Hirokazu; Kuwahara, Akira; Matsuzaki, Toshiya; Irahara, Minoru

    2017-07-01

    Oral oestrogen increases the risk of venous thromboembolism (VTE) and increases production of sex hormone-binding globulin (SHBG) in a dose-dependent manner. SHBG has been suggested to be involved in venous thromboembolism. We examined the effects of oral ultra-low-dose oestradiol on circulating levels of SHBG and coagulation parameters, and we compared the effects to those of transdermal oestradiol. Twenty women received oral oestradiol (500 μg) every day (oral ultra-low-dose group) and 20 women received a transdermal patch (50 μg) as a transdermal group. In addition, the women received dydrogesterone continuously (5 mg) except for women who underwent hysterectomy. Circulating SHBG, antithrombin III (ATIII) activity, d-dimer, thrombin-antithrombin complex and plasmin-α2 plasmin inhibitor complex were measured before and 3 months after the start of treatment. SHBG was significantly increased at 3 months in the oral ultra-low-dose group, but not in the transdermal group. However, percent changes in SHBG were not significantly different between the two groups. In both groups, ATIII was significantly decreased at 3 months. In conclusion, even ultra-low-dose oestradiol orally increases circulating SHBG level. However, the magnitude of change in SHBG caused by oral ultra-low-dose oestradiol is small and is comparable to that caused by transdermal oestradiol. Impact statement Oral oestrogen replacement therapy increases production of SHBG which may be related to increase in VTE risk. However, the effect of oral ultra-low-dose oestradiol on SHBG has not been clarified. Even ultra-low-dose oestradiol orally increases circulating SHBG levels, but the magnitude of change in SHBG caused by oral ultra-low-dose oestradiol is small and is comparable to that caused by transdermal oestradiol. VTE risk in women receiving oral ultra-low-dose oestradiol may be comparable to that in women receiving transdermal oestradiol.

  2. Naltrexone treatment for opioid dependence: Does its effectiveness depend on testing the blockade?

    PubMed Central

    Sullivan, Maria A.; Bisaga, Adam; Mariani, John J.; Glass, Andrew; Levin, Frances R.; Comer, Sandra D.; Nunes, Edward V.

    2013-01-01

    Background FDA approval of long-acting injectable naltrexone (Vivitrol) for opioid dependence highlights the relevance of understanding mechanisms of antagonist treatment. Principles of learning suggest an antagonist works through extinguishing drug-seeking behavior, as episodes of drug use (“testing the blockade”) fail to produce reinforcement. We hypothesized that opiate use would moderate the effect of naltrexone, specifically, that opiate-positive urines precede dropout in the placebo group, but not in the active-medication groups. Methods An 8-week, double-blind, placebo-controlled trial (N=57), compared the efficacy of low (192-mg) and high (384-mg) doses of a long-acting injectable naltrexone (Depotrex) with placebo (Comer et al., 2006). A Cox proportional hazard model was fit, modeling time-to-dropout as a function of treatment assignment and urine toxicology during treatment. Results Interaction of opiate urines with treatment group was significant. Opiate-positive urines predicted dropout on placebo and low-dose, but less so on high-dose naltrexone, where positive urines were more likely followed by sustained abstinence. Among patients with no opiate-positive urines, retention was higher in both low- and high-dose naltrexone conditions, compared to placebo. Conclusions Findings confirm that injection naltrexone produces extinction of drug-seeking behavior after episodes of opiate use. Adequate dosage appears important, as low-dose naltrexone resembled the placebo group; opiate positive urines were likely to be followed by dropout from treatment. The observation of high treatment retention among naltrexone-treated patients who do not test the blockade, suggests naltrexone may also exert direct effects on opiate-taking behavior that do not depend on extinction, perhaps by attenuating craving or normalizing dysregulated hedonic or neuroendocrine systems. PMID:23827259

  3. Naltrexone treatment for opioid dependence: does its effectiveness depend on testing the blockade?

    PubMed

    Sullivan, Maria A; Bisaga, Adam; Mariani, John J; Glass, Andrew; Levin, Frances R; Comer, Sandra D; Nunes, Edward V

    2013-11-01

    FDA approval of long-acting injectable naltrexone (Vivitrol) for opioid dependence highlights the relevance of understanding mechanisms of antagonist treatment. Principles of learning suggest an antagonist works through extinguishing drug-seeking behavior, as episodes of drug use ("testing the blockade") fail to produce reinforcement. We hypothesized that opiate use would moderate the effect of naltrexone, specifically, that opiate-positive urines precede dropout in the placebo group, but not in the active-medication groups. An 8-week, double-blind, placebo-controlled trial (N=57), compared the efficacy of low (192 mg) and high (384 mg) doses of a long-acting injectable naltrexone (Depotrex) with placebo (Comer et al., 2006). A Cox proportional hazard model was fit, modeling time-to-dropout as a function of treatment assignment and urine toxicology during treatment. Interaction of opiate urines with treatment group was significant. Opiate-positive urines predicted dropout on placebo and low-dose, but less so on high-dose naltrexone, where positive urines were more likely followed by sustained abstinence. Among patients with no opiate-positive urines, retention was higher in both low- and high-dose naltrexone conditions, compared to placebo. Findings confirm that injection naltrexone produces extinction of drug-seeking behavior after episodes of opiate use. Adequate dosage appears important, as low-dose naltrexone resembled the placebo group; opiate positive urines were likely to be followed by dropout from treatment. The observation of high treatment retention among naltrexone-treated patients who do not test the blockade, suggests naltrexone may also exert direct effects on opiate-taking behavior that do not depend on extinction, perhaps by attenuating craving or normalizing dysregulated hedonic or neuroendocrine systems. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  4. Ultra-low-dose computed tomographic angiography with model-based iterative reconstruction compared with standard-dose imaging after endovascular aneurysm repair: a prospective pilot study.

    PubMed

    Naidu, Sailen G; Kriegshauser, J Scott; Paden, Robert G; He, Miao; Wu, Qing; Hara, Amy K

    2014-12-01

    An ultra-low-dose radiation protocol reconstructed with model-based iterative reconstruction was compared with our standard-dose protocol. This prospective study evaluated 20 men undergoing surveillance-enhanced computed tomography after endovascular aneurysm repair. All patients underwent standard-dose and ultra-low-dose venous phase imaging; images were compared after reconstruction with filtered back projection, adaptive statistical iterative reconstruction, and model-based iterative reconstruction. Objective measures of aortic contrast attenuation and image noise were averaged. Images were subjectively assessed (1 = worst, 5 = best) for diagnostic confidence, image noise, and vessel sharpness. Aneurysm sac diameter and endoleak detection were compared. Quantitative image noise was 26% less with ultra-low-dose model-based iterative reconstruction than with standard-dose adaptive statistical iterative reconstruction and 58% less than with ultra-low-dose adaptive statistical iterative reconstruction. Average subjective noise scores were not different between ultra-low-dose model-based iterative reconstruction and standard-dose adaptive statistical iterative reconstruction (3.8 vs. 4.0, P = .25). Subjective scores for diagnostic confidence were better with standard-dose adaptive statistical iterative reconstruction than with ultra-low-dose model-based iterative reconstruction (4.4 vs. 4.0, P = .002). Vessel sharpness was decreased with ultra-low-dose model-based iterative reconstruction compared with standard-dose adaptive statistical iterative reconstruction (3.3 vs. 4.1, P < .0001). Ultra-low-dose model-based iterative reconstruction and standard-dose adaptive statistical iterative reconstruction aneurysm sac diameters were not significantly different (4.9 vs. 4.9 cm); concordance for the presence of endoleak was 100% (P < .001). Compared with a standard-dose technique, an ultra-low-dose model-based iterative reconstruction protocol provides

  5. Morphine sulfate and naltrexone hydrochloride extended-release capsules: naltrexone release, pharmacodynamics, and tolerability.

    PubMed

    Johnson, Franklin; Setnik, Beatrice

    2011-01-01

    bioavailability to NS. Although morphine relative bioavailability was similar for MS-sNTC and MSS, mean peak (Emax) visual analog scale (VAS) scores for drug liking and Cole/Addiction Research Center Inventory Stimulation-Euphoria were significantly reduced for MS-sNTC vs MSS (p < 0.001). In these 2 studies, a total of 6 participants had one measurement of plasma naltrexone after MS-sNTW that was above the lower limit of quantification. In the OL safety study, 72/93 participants (77%) had no quantifiable naltrexone concentrations. There was neither evidence of naltrexone accumulation for any participant nor any significant correlation with MS-sNT dose, age, or sex. Of 4 participants with the highest naltrexone concentrations, none had COWS scores consistent with moderate opioid withdrawal symptoms. Only 5 participants had COWS scores consistent with moderate opioid withdrawal; all 5 had not taken MS-sNT as directed. Study populations may not be fully representative of patients receiving opioid therapy for the management of chronic, moderate-to-severe pain and of opioid abusers. When MS-sNT capsules are crushed, all of the sequestered naltrexone (relative to oral NS) is released and immediately available to mitigate morphine-induced effects. When MS-sNT was crushed, the naltrexone released abated drug liking and euphoria relative to that from an equal dose of immediate-release morphine from MSS administration in a majority of participants. Naltrexone concentrations were low over a period of 12 months without evidence of accumulation, and there were no observable opioid withdrawal symptoms when MS-sNT was taken as directed.

  6. Opioid use and dropout in patients receiving oral naltrexone with or without single administration of injection naltrexone.

    PubMed

    Sullivan, Maria A; Bisaga, Adam; Glass, Andrew; Mishlen, Kaitlyn; Pavlicova, Martina; Carpenter, Kenneth M; Mariani, John J; Levin, Frances R; Nunes, Edward V

    2015-02-01

    Adherence to oral naltrexone has been poor and can be improved somewhat with behavioral therapy. We compared behavioral naltrexone therapy (BNT) to compliance enhancement (CE) and tested efficacy of single-dose injection naltrexone (XR-NTX; 384 mg) with behavioral therapies at further improving adherence to oral naltrexone. A 24-week, randomized, placebo-controlled trial (n=125) compared four treatment conditions following inpatient detoxification and oral naltrexone induction: (1) BNT+XR-NTX; (2) BNT+placebo injection; (3) CE+XR-NTX; and (4) CE+placebo injection. All participants were maintained on oral naltrexone throughout the trial. Primary outcome was retention in treatment. Of 89 randomized participants, 78.7% (70/89) completed 4 weeks, 58.2% (54/89) completed 8 weeks, 47.2% (42/89) completed 12 weeks, and 25.8% (23/89) completed 24 weeks. A Cox proportional hazards regression modeled time to dropout as a function of treatment condition, baseline opioid dependence severity (bags per day of heroin use), and their interaction. Interaction of conditions by baseline severity was significant (X3(2)=9.19, p=0.027). For low-severity patients (≤ 6 bags/day), retention was highest in the BNT-XR-NTX group (60% at 6 months), as hypothesized. For high-severity (>6 bags/day) patients, BNT-XR-NTX did not perform as well, due to high early attrition. For low-severity heroin users, single-dose XR-NTX improved long-term treatment retention when combined with behavioral therapy. In higher-severity opioid-dependent patients, XR-NTX was less helpful, perhaps because, combined with oral naltrexone, it produced higher blood levels and more withdrawal discomfort. When cost considerations recommend oral naltrexone following XR-NTX, the latter should be phased in slowly. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  7. Opioid use and dropout in patients receiving oral naltrexone with or without single administration of injection naltrexone

    PubMed Central

    Sullivan, Maria A.; Bisaga, Adam; Glass, Andrew; Mishlen, Kaitlyn; Pavlicova, Martina; Carpenter, Kenneth M.; Mariani, John J; Levin, Frances R.; Nunes, Edward V.

    2015-01-01

    Background Adherence to oral naltrexone has been poor and can be improved somewhat with behavioral therapy. We compared Behavioral Naltrexone Therapy (BNT) to Compliance Enhancement (CE) and tested efficacy of single-dose injection naltrexone (XR-NTX; 384 mg) with behavioral therapies at further improving aherence to oral naltrexone. Methods A 24-week, randomized, placebo-controlled trial (N=125) compared four treatment conditions following inpatient detoxification and oral naltrexone induction: (1) BNT+XR-NTX; (2) BNT+ placebo injection; (3) CE+ XR-NTX; and (4) CE+placebo injection. All participants were maintained on oral naltrexone throughout the trial. Primary outcome was retention in treatment. Results Of 89 randomized participants, 78.7% (70/89) completed 4 weeks, 58.2% (54/89) completed 8 weeks, 47.2% (42/89) completed 12 weeks, and 25.8% (23/89) completed 24 weeks. A Cox proportional hazards regression modeled time to dropout as a function of treatment condition, baseline opioid dependence severity (bags per day of heroin use), and their interaction. Interaction of conditions by baseline severity was significant (X23 = 9.19, p = .027). For low-severity patients (<6 bags/day), retention was highest in the BNT-XRNTX group (60% at 6 months), as hypothesized. For high-severity (> 6 bags/day) patients, BNT-XR-NTX did not perform as well, due to high early attrition. Conclusion For low-severity heroin users, single-dose XR-NTX improved long-term treatment retention when combined with behavioral therapy. In higher-severity opioid-dependent patients, XR-NTX was less helpful, perhaps because, combined with oral naltrexone, it produced higher blood levels and more withdrawal discomfort. When cost considerations recommend oral naltrexone following XR-NTX, the latter should be phased in slowly. PMID:25555621

  8. Ultra Low-Dose Radiation: Stress Responses and Impacts Using Rice as a Grass Model

    PubMed Central

    Rakwal, Randeep; Agrawal, Ganesh Kumar; Shibato, Junko; Imanaka, Tetsuji; Fukutani, Satoshi; Tamogami, Shigeru; Endo, Satoru; Sahoo, Sarata Kumar; Masuo, Yoshinori; Kimura, Shinzo

    2009-01-01

    We report molecular changes in leaves of rice plants (Oryza sativa L. - reference crop plant and grass model) exposed to ultra low-dose ionizing radiation, first using contaminated soil from the exclusion zone around Chernobyl reactor site. Results revealed induction of stress-related marker genes (Northern blot) and secondary metabolites (LC-MS/MS) in irradiated leaf segments over appropriate control. Second, employing the same in vitro model system, we replicated results of the first experiment using in-house fabricated sources of ultra low-dose gamma (γ) rays and selected marker genes by RT-PCR. Results suggest the usefulness of the rice model in studying ultra low-dose radiation response/s. PMID:19399245

  9. Low dose naltrexone in multiple sclerosis: Effects on medication use. A quasi-experimental study.

    PubMed

    Raknes, Guttorm; Småbrekke, Lars

    2017-01-01

    Low dose naltrexone (LDN) has become a popular off-label therapy for multiple sclerosis (MS). A few small, randomized studies indicate that LDN may have beneficial effects in MS and other autoimmune diseases. If proven efficacious, it would be a cheap and safe alternative to the expensive treatments currently recommended for MS. We investigated whether a sudden increase in LDN use in Norway in 2013 was followed by changes in dispensing of other medications used to treat MS. We performed a quasi-experimental before-and-after study based on population data from the Norwegian Prescription Database (NorPD). We included all patients that collected at least one LDN prescription in 2013, and had collected at least two medications with a reimbursement code for MS, or collected a medication with MS as the only indication in 2009 or 2010. Outcomes were differences in cumulative dispensed doses and incidence of users of disease modifying MS therapies, and medications used to treat MS symptoms two years before and two years after dispensing the initial LDN prescription. The eligible 341 patients collected 20 921 prescriptions in the observation period. Apart from changes in line with general trends in MS therapy in Norway, there was no difference in neither dispensed cumulative doses or number of prevalent users of MS specific medication. Initiation of LDN was not followed by reductions of other medications used to treat symptoms associated with MS.

  10. Co-Administration of Low-Dose Naltrexone and Bupropion Reduces Alcohol Drinking in Alcohol-Preferring (P) Rats.

    PubMed

    Nicholson, Emily R; Dilley, Julian E; Froehlich, Janice C

    2018-03-01

    This study examined whether combining naltrexone (NTX) with bupropion (BUP) is more effective in reducing alcohol drinking in alcohol-preferring (P) rats with a genetic predisposition toward high voluntary alcohol intake than either drug alone. Alcohol-experienced, adult, male, P rats were fed NTX alone in a dose of 10.0 mg/kg BW, BUP alone in a dose of 10.0 mg/kg BW, BUP alone in a dose of 20.0 mg/kg BW, NTX (10.0 mg/kg BW) + BUP (10.0 mg/kg BW), or vehicle (VEH) at 1 hour prior to onset of a daily 2-hour alcohol access period for 5 consecutive days. When administered alone, neither NTX (10.0 mg/kg BW) nor BUP, in either of 2 doses (10.0 mg/kg BW or 20.0 mg/kg BW), reduced voluntary alcohol intake in P rats. However, NTX combined with BUP (10.0 mg/kg NTX + 10.0 mg/kg BUP) and given as a single medication significantly reduced alcohol consumption throughout prolonged treatment. Combining low doses of NTX and BUP, each of which is ineffective when given alone, increases the efficacy of the medication. Low drug doses circumvent the problem of negative side effects that can occur with higher doses of either drug. A reduction in side effects can facilitate patient compliance and improve clinical outcomes for alcoholics and heavy drinkers who want to reduce their alcohol intake. The results, together with those from our prior studies, demonstrate the strength of a combinatorial pharmacotherapeutic approach to the treatment of alcohol use disorder. Copyright © 2017 by the Research Society on Alcoholism.

  11. Sinogram restoration for ultra-low-dose x-ray multi-slice helical CT by nonparametric regression

    NASA Astrophysics Data System (ADS)

    Jiang, Lu; Siddiqui, Khan; Zhu, Bin; Tao, Yang; Siegel, Eliot

    2007-03-01

    During the last decade, x-ray computed tomography (CT) has been applied to screen large asymptomatic smoking and nonsmoking populations for early lung cancer detection. Because a larger population will be involved in such screening exams, more and more attention has been paid to studying low-dose, even ultra-low-dose x-ray CT. However, reducing CT radiation exposure will increase noise level in the sinogram, thereby degrading the quality of reconstructed CT images as well as causing more streak artifacts near the apices of the lung. Thus, how to reduce the noise levels and streak artifacts in the low-dose CT images is becoming a meaningful topic. Since multi-slice helical CT has replaced conventional stop-and-shoot CT in many clinical applications, this research mainly focused on the noise reduction issue in multi-slice helical CT. The experiment data were provided by Siemens SOMATOM Sensation 16-Slice helical CT. It included both conventional CT data acquired under 120 kvp voltage and 119 mA current and ultra-low-dose CT data acquired under 120 kvp and 10 mA protocols. All other settings are the same as that of conventional CT. In this paper, a nonparametric smoothing method with thin plate smoothing splines and the roughness penalty was proposed to restore the ultra-low-dose CT raw data. Each projection frame was firstly divided into blocks, and then the 2D data in each block was fitted to a thin-plate smoothing splines' surface via minimizing a roughness-penalized least squares objective function. By doing so, the noise in each ultra-low-dose CT projection was reduced by leveraging the information contained not only within each individual projection profile, but also among nearby profiles. Finally the restored ultra-low-dose projection data were fed into standard filtered back projection (FBP) algorithm to reconstruct CT images. The rebuilt results as well as the comparison between proposed approach and traditional method were given in the results and

  12. Reduced Pro-Inflammatory Cytokines after Eight Weeks of Low-Dose Naltrexone for Fibromyalgia.

    PubMed

    Parkitny, Luke; Younger, Jarred

    2017-04-18

    Fibromyalgia (FM) is a complex, multi-symptom condition that predominantly affects women. The majority of those affected are unlikely to gain significant symptomatic control from the few treatments that are approved for FM. In this 10-week, single-blind, crossover trial we tested the immune effects of eight weeks of oral administration of low-dose naltrexone (LDN). We enrolled eight women with an average age of 46 years, symptom severity of 62 out of 100, and symptom duration of 14 years. We found that LDN was associated with reduced plasma concentrations of interleukin (IL)-1β, IL-1Ra, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12p40, IL-12p70, IL-15, IL-17A, IL-27, interferon (IFN)-α, transforming growth factor (TGF)-α, TGF-β, tumor necrosis factor (TNF)-α, and granulocyte-colony stimulating factor (G-CSF). We also found a 15% reduction of FM-associated pain and an 18% reduction in overall symptoms. The findings of this pilot trial suggest that LDN treatment in fibromyalgia is associated with a reduction of several key pro-inflammatory cytokines and symptoms. The potential role of LDN as an atypical anti-inflammatory medication should be explored further.

  13. Low-dose naltrexone and opioid consumption: a drug utilization cohort study based on data from the Norwegian prescription database.

    PubMed

    Raknes, Guttorm; Småbrekke, Lars

    2017-06-01

    Low-dose naltrexone (LDN) is used in a wide range of conditions, including chronic pain and fibromyalgia. Because of the opioid antagonism of naltrexone, LDN users are probably often warned against concomitant use with opioids. In this study, based on data from the Norwegian prescription database, we examine changes in opioid consumption after starting LDN therapy. We included all Norwegian patients (N = 3775) with at least one recorded LDN prescription in 2013 and at least one dispensed opioid prescription during the 365 days preceding the first LDN prescription. We allocated the patients into three subgroups depending on the number of collected LDN prescriptions and recorded the number of defined daily doses (DDDs) on collected prescriptions on opioids, nonsteroidal anti-inflammatory drugs and other analgesics and antipyretics from the same patients. Among the patients collecting ≥4 LDN prescriptions, annual average opioid consumption was reduced by 41 DDDs per person (46%) compared with that of the previous year. The reduction was 12 DDDs per person (15%) among users collecting two to three prescriptions and no change among those collecting only one LDN prescription. We observed no increase in the number of DDDs in nonsteroidal anti-inflammatory drugs or other analgesics and antipyretics corresponding to the decrease in opioid use. Possibly, LDN users avoided opioids because of warnings on concomitant use or the patients continuing on LDN were less opioid dependent than those terminating LDN. Therapeutic effects of LDN contributing to lower opioid consumption cannot be ruled out. © 2017 The Authors. Pharmacoepidemiology & Drug Safety Published by John Wiley & Sons Ltd. © 2017 The Authors. Pharmacoepidemiology & Drug Safety Published by John Wiley & Sons Ltd.

  14. Relative oral bioavailability of morphine and naltrexone derived from crushed morphine sulfate and naltrexone hydrochloride extended-release capsules versus intact product and versus naltrexone solution: a single-dose, randomized-sequence, open-label, three-way crossover trial in healthy volunteers.

    PubMed

    Johnson, Franklin K; Stark, Jeffrey G; Bieberdorf, Frederick A; Stauffer, Joe

    2010-06-01

    Morphine sulfate/sequestered naltrexone hydrochloride (HCl) (MS-sNT) extended-release fixed-dose combination capsules, approved by the US Food and Drug Administration (FDA) in August 2009 for chronic moderate to severe pain, contain extended-release morphine pellets with a sequestered core of the opioid antagonist naltrexone. MS-sNT was designed so that if the product is tampered with by crushing, the naltrexone becomes bioavailable to mitigate morphine-induced subjective effects, rendering the product less attractive for tampering. The primary aim of this study was to compare the oral bioavailability of naltrexone and its metabolite 6-beta-naltrexol, derived from crushed pellets from MS-sNT capsules, to naltrexone solution. This study also assessed the relative bioavailability of morphine from crushed pellets from MS-sNT capsules and that from the whole, intact product. This single-dose, randomized-sequence, open-label, 3-period, 3-treatment crossover trial was conducted in healthy volunteers. Adults admitted to the study center underwent a 10-hour overnight fast before study drug administration. Each subject received all 3 of the following treatments, 1 per session, separated by a 14-day washout: tampered pellets (crushed for >or=2 minutes with a mortar and pestle) from a 60-mg MS-sNT capsule (60 mg morphine/2.4 mg naltrexone); 60-mg whole, intact MS-sNT capsule; and oral naltrexone HCl (2.4 mg) solution. Plasma concentrations of naltrexone and 6-beta-naltrexol were measured 0 to 168 hours after administration. Morphine pharmaco-kinetics of crushed and whole pellets were determined 0 to 72 hours after administration. The analysis of relative bioavailability was based on conventional FDA criteria for assuming bioequivalence; that is, 90% CIs for ratios of geometric means (natural logarithm [In]-transformed C(max) and AUC) fell within the range of 80% to 125%. Subjects underwent physical examinations, clinical laboratory tests, and ECG at screening and study

  15. Virtual Colonoscopy Screening With Ultra Low-Dose CT and Less-Stressful Bowel Preparation: A Computer Simulation Study

    NASA Astrophysics Data System (ADS)

    Wang, Jing; Wang, Su; Li, Lihong; Fan, Yi; Lu, Hongbing; Liang, Zhengrong

    2008-10-01

    Computed tomography colonography (CTC) or CT-based virtual colonoscopy (VC) is an emerging tool for detection of colonic polyps. Compared to the conventional fiber-optic colonoscopy, VC has demonstrated the potential to become a mass screening modality in terms of safety, cost, and patient compliance. However, current CTC delivers excessive X-ray radiation to the patient during data acquisition. The radiation is a major concern for screening application of CTC. In this work, we performed a simulation study to demonstrate a possible ultra low-dose CT technique for VC. The ultra low-dose abdominal CT images were simulated by adding noise to the sinograms of the patient CTC images acquired with normal dose scans at 100 mA s levels. The simulated noisy sinogram or projection data were first processed by a Karhunen-Loeve domain penalized weighted least-squares (KL-PWLS) restoration method and then reconstructed by a filtered backprojection algorithm for the ultra low-dose CT images. The patient-specific virtual colon lumen was constructed and navigated by a VC system after electronic colon cleansing of the orally-tagged residue stool and fluid. By the KL-PWLS noise reduction, the colon lumen can successfully be constructed and the colonic polyp can be detected in an ultra low-dose level below 50 mA s. Polyp detection can be found more easily by the KL-PWLS noise reduction compared to the results using the conventional noise filters, such as Hanning filter. These promising results indicate the feasibility of an ultra low-dose CTC pipeline for colon screening with less-stressful bowel preparation by fecal tagging with oral contrast.

  16. A Combination of Buprenorphine and Naltrexone Blocks Compulsive Cocaine Intake in Rodents Without Producing Dependence

    PubMed Central

    Wee, Sunmee; Vendruscolo, Leandro F.; Misra, Kaushik K.; Schlosburg, Joel E.; Koob, George F.

    2012-01-01

    Buprenorphine, a synthetic opioid that acts at both μ and κ opioid receptors, can decrease cocaine use in individuals with opioid addiction. However, the potent agonist action of buprenorphine at μ opioid receptors raises its potential for creating opioid dependence in non–opioid-dependent cocaine abusers. Here, we tested the hypothesis that a combination of buprenorphine and naltrexone (a potent μ opioid antagonist with weaker δ and κ antagonist properties) could block compulsive cocaine self-administration without producing opioid dependence. The effects of buprenorphine and various doses of naltrexone on cocaine self-administration were assessed in rats that self-administered cocaine under conditions of either short access (noncompulsive cocaine seeking) or extended access (compulsive cocaine seeking). Buprenorphine alone reproducibly decreased cocaine self-administration. Although this buprenorphine-alone effect was blocked in a dose-dependent manner by naltrexone in both the short-access and the extended-access groups, the combination of the lowest dose of naltrexone with buprenorphine blocked cocaine self-administration in the extended-access group but not in the short-access group. Rats given this low dose of naltrexone with buprenorphine did not exhibit the physical opioid withdrawal syndrome seen in rats treated with buprenorphine alone, and naltrexone at this dose did not block κ agonist–induced analgesia. The results suggest that the combination of buprenorphine and naltrexone at an appropriate dosage decreases compulsive cocaine self-administration with minimal liability to produce opioid dependence and may be useful as a treatment for cocaine addiction. PMID:22875830

  17. A combination of buprenorphine and naltrexone blocks compulsive cocaine intake in rodents without producing dependence.

    PubMed

    Wee, Sunmee; Vendruscolo, Leandro F; Misra, Kaushik K; Schlosburg, Joel E; Koob, George F

    2012-08-08

    Buprenorphine, a synthetic opioid that acts at both μ and κ opioid receptors, can decrease cocaine use in individuals with opioid addiction. However, the potent agonist action of buprenorphine at μ opioid receptors raises its potential for creating opioid dependence in non-opioid-dependent cocaine abusers. Here, we tested the hypothesis that a combination of buprenorphine and naltrexone (a potent μ opioid antagonist with weaker δ and κ antagonist properties) could block compulsive cocaine self-administration without producing opioid dependence. The effects of buprenorphine and various doses of naltrexone on cocaine self-administration were assessed in rats that self-administered cocaine under conditions of either short access (noncompulsive cocaine seeking) or extended access (compulsive cocaine seeking). Buprenorphine alone reproducibly decreased cocaine self-administration. Although this buprenorphine-alone effect was blocked in a dose-dependent manner by naltrexone in both the short-access and the extended-access groups, the combination of the lowest dose of naltrexone with buprenorphine blocked cocaine self-administration in the extended-access group but not in the short-access group. Rats given this low dose of naltrexone with buprenorphine did not exhibit the physical opioid withdrawal syndrome seen in rats treated with buprenorphine alone, and naltrexone at this dose did not block κ agonist-induced analgesia. The results suggest that the combination of buprenorphine and naltrexone at an appropriate dosage decreases compulsive cocaine self-administration with minimal liability to produce opioid dependence and may be useful as a treatment for cocaine addiction.

  18. Safety and tolerability of low-dose naltrexone therapy in children with moderate to severe Crohn's disease: a pilot study.

    PubMed

    Smith, Jill P; Field, Douglas; Bingaman, Sandra I; Evans, Robert; Mauger, David T

    2013-04-01

    There is an unmet need for safe and effective medicines to treat children with Crohn's disease. Recently, investigations have shown an association between endogenous opioid peptides and inflammatory cells. The aims of this study were to evaluate the safety and tolerability of an opioid antagonist, naltrexone, in children with moderate to severe Crohn's disease. A pilot clinical trial was conducted in children with moderate to severe Crohn's disease. Fourteen subjects with a mean age of 12.3 years (range, 8 to 17 y) were enrolled. Children were randomized to placebo or naltrexone (0.1 mg/kg) orally for 8 weeks followed by open-labeled treatment with 8 additional weeks of naltrexone. Safety and toxicity were monitored by physical examinations and blood chemistries. Clinical activity was assessed by the Pediatric Crohn's Disease Activity Index (PCDAI) and Quality of life was monitored by the Impact III survey. Oral naltrexone was well tolerated without any serious adverse events in children with moderate to severe Crohn's disease. PCDAI scores significantly decreased from pretreatment values (34.2±3.3) with an 8-week course of naltrexone therapy (21.7±3.9) (P=0.005). Twenty-five percent of those treated with naltrexone were considered in remission (score ≤10) and 67% had improved with mild disease activity (decrease in PCDAI score by at least 10 points) at the end of the study. Systemic and social quality of life improved with naltrexone treatment (P=0.035). Naltrexone therapy seems safe with limited toxicity when given to children with Crohn's disease and may reduce disease activity.

  19. A photon recycling approach to the denoising of ultra-low dose X-ray sequences.

    PubMed

    Hariharan, Sai Gokul; Strobel, Norbert; Kaethner, Christian; Kowarschik, Markus; Demirci, Stefanie; Albarqouni, Shadi; Fahrig, Rebecca; Navab, Nassir

    2018-06-01

    Clinical procedures that make use of fluoroscopy may expose patients as well as the clinical staff (throughout their career) to non-negligible doses of radiation. The potential consequences of such exposures fall under two categories, namely stochastic (mostly cancer) and deterministic risks (skin injury). According to the "as low as reasonably achievable" principle, the radiation dose can be lowered only if the necessary image quality can be maintained. Our work improves upon the existing patch-based denoising algorithms by utilizing a more sophisticated noise model to exploit non-local self-similarity better and this in turn improves the performance of low-rank approximation. The novelty of the proposed approach lies in its properly designed and parameterized noise model and the elimination of initial estimates. This reduces the computational cost significantly. The algorithm has been evaluated on 500 clinical images (7 patients, 20 sequences, 3 clinical sites), taken at ultra-low dose levels, i.e. 50% of the standard low dose level, during electrophysiology procedures. An average improvement in the contrast-to-noise ratio (CNR) by a factor of around 3.5 has been found. This is associated with an image quality achieved at around 12 (square of 3.5) times the ultra-low dose level. Qualitative evaluation by X-ray image quality experts suggests that the method produces denoised images that comply with the required image quality criteria. The results are consistent with the number of patches used, and they demonstrate that it is possible to use motion estimation techniques and "recycle" photons from previous frames to improve the image quality of the current frame. Our results are comparable in terms of CNR to Video Block Matching 3D-a state-of-the-art denoising method. But qualitative analysis by experts confirms that the denoised ultra-low dose X-ray images obtained using our method are more realistic with respect to appearance.

  20. SAFETY AND TOLERABILITY OF LOW DOSE NALTREXONE THERAPY IN CHILDREN WITH MODERATE TO SEVERE CROHN’S DISEASE: A PILOT STUDY

    PubMed Central

    Smith, Jill P.; Field, Douglas; Bingaman, Sandra; Evans, Robert; Mauger, David

    2012-01-01

    Background There is an unmet need for safe and effective medicines to treat children with Crohn’s disease. Recently, investigations have shown an association between endogenous opioid peptides and inflammatory cells. Aims The aims of this study were to evaluate the safety and tolerability of an opioid antagonist, naltrexone, in children with moderate to severe Crohn’s disease. Methods A pilot clinical trial was conducted in children with moderate to severe Crohn’s disease. Fourteen subjects with a mean age of 12.3 years (8–17, range) were enrolled. Children were randomized to placebo or naltrexone 0.1 mg/kg orally for 8 weeks followed by open-labeled treatment with 8 additional weeks of naltrexone. Safety and toxicity were monitored by physical examinations and blood chemistries. Clinical activity was assessed by the PCDAI (Pediatric Crohn’s Disease Activity Index) and Quality of life was monitored by the Impact III survey. Results Oral naltrexone was well tolerated without any serious adverse events in children with moderate to severe Crohn’s disease. PCDAI scores significantly decreased from pretreatment values (34.2±3.3) with an eight-week course of naltrexone therapy (21.7±3.9) (p=0.005). Twenty-five percent of those treated with naltrexone were considered in remission (score < 10) and 67% had improved with mild disease activity (decrease PCDAI score by at least 10 points) at the end of the study. Systemic and social quality of life improved with naltrexone treatment (p=0.035). Conclusions Naltrexone therapy appears safe with limited toxicity when given to children with Crohn’s disease and may reduce disease activity. PMID:23188075

  1. Effect of food on the pharmacokinetics of oxycodone and naltrexone from ALO-02, an extended release formulation of oxycodone with sequestered naltrexone.

    PubMed

    Gandelman, Kuan; Lamson, Michael; Salageanu, Joanne; Bramson, Candace; Matschke, Kyle; Malhotra, Bimal

    2015-09-01

    food (whole capsule, fed vs. fasted) or of sprinkling on applesauce (pellets vs. whole capsule, fasted) on oxycodone bioavailability. The Test/Reference ratios of adjusted geometric means for oxycodone AUCinf , AUClast , and Cmax were 99.2%, 100%, and 107%, respectively, for the effect of food; and 101%, 101%, and 97.5%, respectively, for the effect of sprinkling on applesauce. The 90% confidence intervals contained entirely within the bioequivalence limits of 80% to 125% for each comparison. Naltrexone remained sequestered during each treatment, based on the sporadic and low measurable plasma concentrations of naltrexone and 6-ß-naltrexol. Single doses of ALO-02 40 mg were well tolerated, and adverse events were mild, with no apparent difference in frequency for all 3 treatments. Results indicate that ALO-02 can be administered without regard to food. Also, the contents of ALO-02 can be sprinkled over applesauce and consumed without chewing as an alternative treatment option by subjects with difficulty swallowing. Naltrexone remained sequestered in the ALO-02 formulation under all 3 treatments. © 2015, The American College of Clinical Pharmacology.

  2. Ex vivo studies for the passive transdermal delivery of low-dose naltrexone from a cream; detection of naltrexone and its active metabolite, 6β-naltrexol, using a novel LC Q-ToF MS assay.

    PubMed

    Dodou, Kalliopi; Armstrong, Andrew; Kelly, Ivan; Wilkinson, Simon; Carr, Kevin; Shattock, Paul; Whiteley, Paul

    2015-01-01

    Naltrexone (NTX) is a long-acting opiate antagonist. Low-dose naltrexone (LDN) therapy has shown promising results in the treatment of several autoimmune disorders. Our aim was to formulate NTX into a cream for the delivery of LDN and develop an analytical technique for the quantification of NTX and its active metabolite 6-β-naltrexol (NTXol) during transdermal diffusion cell permeation studies. A 1% w/w NTX cream was formulated and drug permeation was examined over 24 h using static Franz diffusion cells mounted with pig skin. A Liquid Chromatography Quadrupole-Time of Flight Mass Spectrometry (LC-MS Q-ToF) method was developed for the detection of NTX and NTXol in the receptor solution, skin membrane and residual cream on the donor chamber after completion of the diffusion studies. The cream formulation exhibited steady state release of NTX over 24 h after an initial lag time of 2.74 h. The bioconversion of NTX to NTXol in the skin membrane was 1.1%. It was concluded that the cream may be an effective formulation for the sustained transdermal delivery of LDN. The novel LC Q-ToF MS method allowed the accurate measurement of NTX and NTXol levels across the diffusion cell assemblies and the quantification of NTX metabolism in the skin.

  3. Low-dose naltrexone (LDN): A promising treatment in immune-related diseases and cancer therapy.

    PubMed

    Li, Zijian; You, Yue; Griffin, Noreen; Feng, Juan; Shan, Fengping

    2018-06-06

    Naltrexone, a non-selective antagonist of opioid receptors, is mainly used as rehabilitation therapy for discharged opiate addicts to eliminate addiction in order to maintain a normal life and prevent or reduce relapse. In recent years, there have been some novel and significant findings on the off-label usage of naltrexone. Within a specific dosage window, LDN can act as an immunomodulator in multiple autoimmune diseases and malignant tumors as well as alleviate the symptoms of some mental disorders. The results of increasing studies indicate that LDN exerts its immunoregulatory activity by binding to opioid receptors in or on immune cells and tumor cells. These new discoveries indicate that LDN may become a promising immunomodulatory agent in the therapy for cancer and many immune-related diseases. In this article, we review the pharmacological functions and mechanisms of LDN as well as its clinical therapeutic potential as revealed by our team and other researchers. Copyright © 2018. Published by Elsevier B.V.

  4. Opioid Challenge Evaluation of Blockade by Extended-Release Naltrexone in Opioid-Abusing Adults: Dose-Effects and Time-Course

    PubMed Central

    Bigelow, George E.; Preston, Kenzie L.; Schmittner, John; Dong, Qunming; Gastfriend, David R.

    2013-01-01

    Background Oral naltrexone's effectiveness as an opioid antagonist has been limited due to poor patient adherence. A long-acting naltrexone formulation may be beneficial. This study evaluated the effects of extended-release injectable naltrexone (XR-NTX), targeted for a one-month duration of action, in blocking opioid agonist challenge effects in humans. Methods Outpatient non-dependent opioid abusers (N=27) were randomly assigned to a single double-blind IM administration of 75, 150, or 300 mg XR-NTX. To assess the extent of opioid blockade, hydromorphone challenges (0, 3, 4.5, 6 mg IM in ascending order at 1-hr intervals [up to 13.5 mg total]) were given at pretreatment baseline and on days 7, 14, 21, 28, 42, and 56. Opioid blockade was assessed via (1) tolerability of the ascending hydromorphone doses; (2) Visual Analog Scale (VAS) ratings of subjective opioid effects and (3) pupil diameter. Effects on the VAS and pupils were assessed via the slope of the time-action function over ascending hydromorphone doses, with zero slope indicating complete blockade. Results Blockade of the VAS “any drug effect” response to 3 mg hydromorphone was complete for 14, 21, and 28 days, respectively, for the XR-NTX doses of 75, 150 and 300 mg. Subjective effects were more readily blocked than was pupil constriction. Higher hydromorphone doses produced only modest increases in agonist effects. With the 300 mg XR-NTX dose the slope of VAS responses remained at or near zero for one month even with maximal cumulative hydromorphone dosing. Conclusions These data quantify the month-long opioid blockade underlying XR-NTX's efficacy in opioid dependence treatment. PMID:22079773

  5. Effect of ultra-low doses, ASIR and MBIR on density and noise levels of MDCT images of dental implant sites.

    PubMed

    Widmann, Gerlig; Al-Shawaf, Reema; Schullian, Peter; Al-Sadhan, Ra'ed; Hörmann, Romed; Al-Ekrish, Asma'a A

    2017-05-01

    Differences in noise and density values in MDCT images obtained using ultra-low doses with FBP, ASIR, and MBIR may possibly affect implant site density analysis. The aim of this study was to compare density and noise measurements recorded from dental implant sites using ultra-low doses combined with FBP, ASIR, and MBIR. Cadavers were scanned using a standard protocol and four low-dose protocols. Scans were reconstructed using FBP, ASIR-50, ASIR-100, and MBIR, and either a bone or standard reconstruction kernel. Density (mean Hounsfield units [HUs]) of alveolar bone and noise levels (mean standard deviation of HUs) was recorded from all datasets and measurements were compared by paired t tests and two-way ANOVA with repeated measures. Significant differences in density and noise were found between the reference dose/FBP protocol and almost all test combinations. Maximum mean differences in HU were 178.35 (bone kernel) and 273.74 (standard kernel), and in noise, were 243.73 (bone kernel) and 153.88 (standard kernel). Decreasing radiation dose increased density and noise regardless of reconstruction technique and kernel. The effect of reconstruction technique on density and noise depends on the reconstruction kernel used. • Ultra-low-dose MDCT protocols allowed more than 90 % reductions in dose. • Decreasing the dose generally increased density and noise. • Effect of IRT on density and noise varies with reconstruction kernel. • Accuracy of low-dose protocols for interpretation of bony anatomy not known. • Effect of low doses on accuracy of computer-aided design models unknown.

  6. New opioid receptor antagonist: Naltrexone-14-O-sulfate synthesis and pharmacology.

    PubMed

    Zádor, Ferenc; Király, Kornél; Váradi, András; Balogh, Mihály; Fehér, Ágnes; Kocsis, Dóra; Erdei, Anna I; Lackó, Erzsébet; Zádori, Zoltán S; Hosztafi, Sándor; Noszál, Béla; Riba, Pál; Benyhe, Sándor; Fürst, Susanna; Al-Khrasani, Mahmoud

    2017-08-15

    Opioid antagonists, naloxone and naltrexone have long been used in clinical practice and research. In addition to their low selectivity, they easily pass through the blood-brain barrier. Quaternization of the amine group in these molecules, (e.g. methylnaltrexone) results in negligible CNS penetration. In addition, zwitterionic compounds have been reported to have limited CNS access. The current study, for the first time gives report on the synthesis and the in vitro [competition binding, G-protein activation, isolated mouse vas deferens (MVD) and mouse colon assay] pharmacology of the zwitterionic compound, naltrexone-14-O-sulfate. Naltrexone, naloxone, and its 14-O-sulfate analogue were used as reference compounds. In competition binding assays, naltrexone-14-O-sulfate showed lower affinity for µ, δ or κ opioid receptor than the parent molecule, naltrexone. However, the μ/κ opioid receptor selectivity ratio significantly improved, indicating better selectivity. Similar tendency was observed for naloxone-14-O-sulfate when compared to naloxone. Naltrexone-14-O-sulfate failed to activate [ 35 S]GTPγS-binding but inhibit the activation evoked by opioid agonists (DAMGO, Ile 5,6 deltorphin II and U69593), similarly to the reference compounds. Schild plot constructed in MVD revealed that naltrexone-14-O-sulfate acts as a competitive antagonist. In mouse colon, naltrexone-14-O-sulfate antagonized the inhibitory effect of morphine with lower affinity compared to naltrexone and higher affinity when compared to naloxone or naloxone-14-O-sulfate. In vivo (mouse tail-flick test), subcutaneously injected naltrexone-14-O-sulfate antagonized morphine's antinociception in a dose-dependent manner, indicating it's CNS penetration, which was unexpected from such zwitter ionic structure. Future studies are needed to evaluate it's pharmacokinetic profile. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Early detection of lung cancer using ultra-low-dose computed tomography in coronary CT angiography scans among patients with suspected coronary heart disease.

    PubMed

    Zanon, Matheus; Pacini, Gabriel Sartori; de Souza, Vinicius Valério Silveiro; Marchiori, Edson; Meirelles, Gustavo Souza Portes; Szarf, Gilberto; Torres, Felipe Soares; Hochhegger, Bruno

    2017-12-01

    To assess whether an additional chest ultra-low-dose CT scan to the coronary CT angiography protocol can be used for lung cancer screening among patients with suspected coronary artery disease. 175 patients underwent coronary CT angiography for assessment of coronary artery disease, additionally undergoing ultra-low-dose CT screening to early diagnosis of lung cancer in the same scanner (80kVp and 15mAs). Patients presenting pulmonary nodules were followed-up for two years, repeating low-dose CTs in intervals of 3, 6, or 12 months based on nodule size and growth rate in accordance with National Comprehensive Cancer Network guidelines. Ultra-low-dose CT identified 71 patients with solitary pulmonary nodules (41%), with a mean diameter of 5.50±4.00mm. Twenty-eight were >6mm, and in 79% (n=22) of these cases they were false positive findings, further confirmed by follow-up (n=20), resection (n=1), or biopsy (n=1). Lung cancer was detected in six patients due to CT screening (diagnostic yield: 3%). Among these, four cases could not be detected in the cardiac field of view. Most patients were in early stages of the disease. Two patients diagnosed at advanced stages died due to cancer complications. The addition of the ultra-low-dose CT scan represented a radiation dose increment of 1.22±0.53% (effective dose, 0.11±0.03mSv). Lung cancer might be detected using additional ultra-low-dose protocols in coronary CT angiography scans among patients with suspected coronary artery disease. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Performance evaluation of multi-material electronic cleansing for ultra-low-dose dual-energy CT colonography

    NASA Astrophysics Data System (ADS)

    Tachibana, Rie; Kohlhase, Naja; Näppi, Janne J.; Hironaka, Toru; Ota, Junko; Ishida, Takayuki; Regge, Daniele; Yoshida, Hiroyuki

    2016-03-01

    Accurate electronic cleansing (EC) for CT colonography (CTC) enables the visualization of the entire colonic surface without residual materials. In this study, we evaluated the accuracy of a novel multi-material electronic cleansing (MUMA-EC) scheme for non-cathartic ultra-low-dose dual-energy CTC (DE-CTC). The MUMA-EC performs a wateriodine material decomposition of the DE-CTC images and calculates virtual monochromatic images at multiple energies, after which a random forest classifier is used to label the images into the regions of lumen air, soft tissue, fecal tagging, and two types of partial-volume boundaries based on image-based features. After the labeling, materials other than soft tissue are subtracted from the CTC images. For pilot evaluation, 384 volumes of interest (VOIs), which represented sources of subtraction artifacts observed in current EC schemes, were sampled from 32 ultra-low-dose DE-CTC scans. The voxels in the VOIs were labeled manually to serve as a reference standard. The metric for EC accuracy was the mean overlap ratio between the labels of the reference standard and the labels generated by the MUMA-EC, a dualenergy EC (DE-EC), and a single-energy EC (SE-EC) scheme. Statistically significant differences were observed between the performance of the MUMA/DE-EC and the SE-EC methods (p<0.001). Visual assessment confirmed that the MUMA-EC generated less subtraction artifacts than did DE-EC and SE-EC. Our MUMA-EC scheme yielded superior performance over conventional SE-EC scheme in identifying and minimizing subtraction artifacts on noncathartic ultra-low-dose DE-CTC images.

  9. Low dose naltrexone (LDN) enhances maturation of bone marrow dendritic cells (BMDCs).

    PubMed

    Meng, Jingjuan; Meng, Yiming; Plotnikoff, Nicholas P; Youkilis, Gene; Griffin, Noreen; Shan, Fengping

    2013-12-01

    It has been demonstrated previously that immune cell activation and proliferation were sensitive to the effects of naltrexone, a non-peptidic δ-opioid receptor selective antagonist and opioid receptors on BMDCs have been detected [1]. However, there is little prior data published on naltrexone and DCs. Therefore, we hypothesized that LDN could exert modulating effect on BMDCs. In present study, we studied influence of LDN on both phenotypic and functional maturation of BMDCs. Changes of BMDC post-treatment with LDN were evaluated using conventional light microscope and transmission electron microscopy (TEM); flow cytometry(FCM); cytochemistry; acid phosphatase activity(ACP) test; FITC-dextran bio-assay; mixed lymphocytes and enzyme-linked immunosorbent assay (ELISA). We have found that LDN enhances maturation of BMDCs as evidenced by 1) up-regulating the expression of MHC II, CD40, CD83, CD80 and CD86 molecules on BMDCs; 2) down-regulating the rates of pinocytosis and phagocytosis accompanied by the results of decreased ACP, and FITC-dextran bio-assay; 3) mounting potential of BMDCs to drive T cell; and 4) inducing secretion of higher levels of IL-12 and TNF-α. It is therefore concluded that LDN can efficiently promote the maturation of BMDCs via precise modulation inside and outside BMDCs. Our study has provided meaningful mode of action on the role of LDN in immunoregulation, and rationale on future application of LDN for enhancing host immunity in cancer therapy and potent use in the design of DC-based vaccines for a number of diseases.

  10. On the behavioural specificity of hypophagia induced in male rats by mCPP, naltrexone, and their combination.

    PubMed

    Wright, F L; Rodgers, R J

    2014-02-01

    Serotonergic (5-hydroxytryptamine, 5-HT) and opioidergic mechanisms are intimately involved in appetite regulation. In view of recent evidence of positive anorectic interactions between opioid and various non-opioid substrates, our aim was to assess the behavioural specificity of anorectic responses to the opioid receptor antagonist naltrexone, the 5-HT2C/1B receptor agonist mCPP and their combination. Behavioural profiling techniques, including the behavioural satiety sequence (BSS), were used to examine acute drug effects in non-deprived male rats tested with palatable mash. Experiment 1 characterised the dose-response profile of mCPP (0.1-3.0 mg/kg), while experiment 2 assessed the effects of combined treatment with a sub-anorectic dose of mCPP (0.1 mg/kg) and one of two low doses of naltrexone (0.1 and 1.0 mg/kg). Experiment 1 confirmed the dose-dependent anorectic efficacy of mCPP, with robust effects on intake and feeding-related measures observed at 3.0 mg/kg. However, that dose was also associated with other behavioural alterations including increased grooming, reductions in locomotion and sniffing, and disruption of the BSS. In experiment 2, naltrexone dose-dependently reduced food intake and time spent feeding, effects accompanied by a behaviourally selective acceleration in the BSS. However, the addition of 0.1 mg/kg mCPP did not significantly alter the behavioural changes observed in response to either dose of naltrexone given alone. In contrast to recently reported positive anorectic interactions involving low-dose combinations of opioid receptor antagonists or mCPP with cannabinoid CB1 receptor antagonists, present results would not appear to provide any support for potentially clinically relevant anorectic interactions between opioid and 5-HT2C/1B receptor mechanisms.

  11. Naltrexone in the treatment of adolescent sexual offenders.

    PubMed

    Ryback, Ralph S

    2004-07-01

    Naltrexone is a long-acting opioid used clinically in alcoholism, drug abuse, bulimia nervosa, obsessive-compulsive disorder, and impulse-control disorders. This study investigated whether naltrexone can decrease sexual arousal in legally adjudicated adolescent sexual offenders. In an open-ended prospective study, naltrexone was given to 21 adolescents participating in an inpatient adolescent sexual offenders program who met any of the self-reported criteria of (1) masturbating 3 or more times per day, (2) feeling unable to control arousal, (3) spending more than 30% of awake time in sexual fantasies, or (4) having sexual fantasies or behavior that regularly intruded into and interfered with their functioning in the treatment program. After having been treated for more than 2 months, 13 patients had their naltrexone administratively stopped, thus providing a before, during, after, and resumption-of-treatment design. Behavioral changes were monitored daily with a fantasy-tracking log and a masturbation log. A positive result was recorded if there was more than a 30% decrease in any self-reported criterion that was applicable to each specific patient and this benefit lasted at least 4 months. Data were collected from July 2000 to December 2002. Leuprolide was given if naltrexone was not sufficiently helpful in controlling sexual impulses and arousal. Fifteen of 21 patients were considered to have a positive result and continued to respond for at least 4 months to an average dose of 160 mg per day with decreased sexual fantasies and masturbation. Dosages above 200 mg per day were not more helpful. Administrative discontinuation of naltrexone in a subset of 13 patients resulted in reoccurrence of symptoms that began when the dose taper reached 50 mg per day. There were no changes in clinical chemistries. Five of 6 patients who did not benefit from naltrexone responded favorably to leuprolide. Naltrexone at dosages of 100 to 200 mg per day provides a safe first step in

  12. Ultra low-dose CT attenuation correction in PET SPM

    NASA Astrophysics Data System (ADS)

    Wang, Shyh-Jen; Yang, Bang-Hung; Tsai, Chia-Jung; Yang, Ching-Ching; Lee, Jason J. S.; Wu, Tung-Hsin

    2010-07-01

    The use of CT images for attenuation correction (CTAC) allows significantly shorter scanning time and a high quality noise-free attenuation map compared with conventional germanium-68 transmission scan because at least 10 4 times greater of photon flux would be generated from a CT scan under standard operating condition. However, this CTAC technique would potentially introduce more radiation risk to the patients owing to the higher radiation exposure from CT scan. Statistic parameters mapping (SPM) is a prominent technique in nuclear medicine community for the analysis of brain imaging data. The purpose of this study is to assess the feasibility of low-dose CT (LDCT) and ultra low-dose CT (UDCT) in PET SPM applications. The study was divided into two parts. The first part was to evaluate of tracer uptake distribution pattern and quantity analysis by using the striatal phantom to initially assess the feasibility of AC for clinical purpose. The second part was to examine the group SPM analysis using the Hoffman brain phantom. The phantom study is to simulate the human brain and to reduce the experimental uncertainty of real subjects. The initial studies show that the results of PET SPM analysis have no significant differences between LDCT and UDCT comparing to the current used default CTAC. Moreover, the dose of the LDCT is lower than that of the default CT by a factor of 9, and UDCT can even yield a 42 times dose reduction. We have demonstrated the SPM results while using LDCT and UDCT for PET AC is comparable to those using default CT setting, suggesting their feasibility in PET SPM applications. In addition, the necessity of UDCT in PET SPM studies to avoid excess radiation dose is also evident since most of the subjects involved are non-cancer patients or children and some normal subjects are even served as a comparison group in the experiment. It is our belief that additional attempts to decrease the radiation dose would be valuable, especially for children and

  13. Combination of Continuous Dexmedetomidine Infusion with Titrated Ultra-Low-Dose Propofol-Fentanyl for an Awake Craniotomy

    PubMed Central

    Das, Samaresh; Al-Mashani, Ali; Suri, Neelam; Salhotra, Neeraj; Chatterjee, Nilay

    2016-01-01

    An awake craniotomy is a continuously evolving technique used for the resection of brain tumours from the eloquent cortex. We report a 29-year-old male patient who presented to the Khoula Hospital, Muscat, Oman, in 2016 with a two month history of headaches and convulsions due to a space-occupying brain lesion in close proximity with the left motor cortex. An awake craniotomy was conducted using a scalp block, continuous dexmedetomidine infusion and a titrated ultra-low-dose of propofolfentanyl. The patient remained comfortable throughout the procedure and the intraoperative neuropsychological tests, brain mapping and tumour resection were successful. This case report suggests that dexmedetomidine in combination with titrated ultra-low-dose propofolfentanyl are effective options during an awake craniotomy, ensuring optimum sedation, minimal disinhibition and a rapid recovery. To the best of the authors’ knowledge, this is the first awake craniotomy conducted successfully in Oman. PMID:27606116

  14. Ultra-low dose CT attenuation correction for PET/CT: analysis of sparse view data acquisition and reconstruction algorithms

    NASA Astrophysics Data System (ADS)

    Rui, Xue; Cheng, Lishui; Long, Yong; Fu, Lin; Alessio, Adam M.; Asma, Evren; Kinahan, Paul E.; De Man, Bruno

    2015-09-01

    For PET/CT systems, PET image reconstruction requires corresponding CT images for anatomical localization and attenuation correction. In the case of PET respiratory gating, multiple gated CT scans can offer phase-matched attenuation and motion correction, at the expense of increased radiation dose. We aim to minimize the dose of the CT scan, while preserving adequate image quality for the purpose of PET attenuation correction by introducing sparse view CT data acquisition. We investigated sparse view CT acquisition protocols resulting in ultra-low dose CT scans designed for PET attenuation correction. We analyzed the tradeoffs between the number of views and the integrated tube current per view for a given dose using CT and PET simulations of a 3D NCAT phantom with lesions inserted into liver and lung. We simulated seven CT acquisition protocols with {984, 328, 123, 41, 24, 12, 8} views per rotation at a gantry speed of 0.35 s. One standard dose and four ultra-low dose levels, namely, 0.35 mAs, 0.175 mAs, 0.0875 mAs, and 0.043 75 mAs, were investigated. Both the analytical Feldkamp, Davis and Kress (FDK) algorithm and the Model Based Iterative Reconstruction (MBIR) algorithm were used for CT image reconstruction. We also evaluated the impact of sinogram interpolation to estimate the missing projection measurements due to sparse view data acquisition. For MBIR, we used a penalized weighted least squares (PWLS) cost function with an approximate total-variation (TV) regularizing penalty function. We compared a tube pulsing mode and a continuous exposure mode for sparse view data acquisition. Global PET ensemble root-mean-squares-error (RMSE) and local ensemble lesion activity error were used as quantitative evaluation metrics for PET image quality. With sparse view sampling, it is possible to greatly reduce the CT scan dose when it is primarily used for PET attenuation correction with little or no measureable effect on the PET image. For the four ultra-low dose

  15. Ultra-low dose CT attenuation correction for PET/CT: analysis of sparse view data acquisition and reconstruction algorithms

    PubMed Central

    Rui, Xue; Cheng, Lishui; Long, Yong; Fu, Lin; Alessio, Adam M.; Asma, Evren; Kinahan, Paul E.; De Man, Bruno

    2015-01-01

    For PET/CT systems, PET image reconstruction requires corresponding CT images for anatomical localization and attenuation correction. In the case of PET respiratory gating, multiple gated CT scans can offer phase-matched attenuation and motion correction, at the expense of increased radiation dose. We aim to minimize the dose of the CT scan, while preserving adequate image quality for the purpose of PET attenuation correction by introducing sparse view CT data acquisition. Methods We investigated sparse view CT acquisition protocols resulting in ultra-low dose CT scans designed for PET attenuation correction. We analyzed the tradeoffs between the number of views and the integrated tube current per view for a given dose using CT and PET simulations of a 3D NCAT phantom with lesions inserted into liver and lung. We simulated seven CT acquisition protocols with {984, 328, 123, 41, 24, 12, 8} views per rotation at a gantry speed of 0.35 seconds. One standard dose and four ultra-low dose levels, namely, 0.35 mAs, 0.175 mAs, 0.0875 mAs, and 0.04375 mAs, were investigated. Both the analytical FDK algorithm and the Model Based Iterative Reconstruction (MBIR) algorithm were used for CT image reconstruction. We also evaluated the impact of sinogram interpolation to estimate the missing projection measurements due to sparse view data acquisition. For MBIR, we used a penalized weighted least squares (PWLS) cost function with an approximate total-variation (TV) regularizing penalty function. We compared a tube pulsing mode and a continuous exposure mode for sparse view data acquisition. Global PET ensemble root-mean-squares-error (RMSE) and local ensemble lesion activity error were used as quantitative evaluation metrics for PET image quality. Results With sparse view sampling, it is possible to greatly reduce the CT scan dose when it is primarily used for PET attenuation correction with little or no measureable effect on the PET image. For the four ultra-low dose levels

  16. Effects of baclofen and naltrexone, alone and in combination, on the consumption of palatable food in male rats.

    PubMed

    Avena, Nicole M; Bocarsly, Miriam E; Murray, Susan; Gold, Mark S

    2014-10-01

    Excess consumption of palatable food has been shown to affect reward-related brain regions, and pharmaceutical treatments for drug addiction may also be effective in treating overeating of such foods. The GABA-B agonist baclofen and opioid antagonist naltrexone have both been used to treat addiction, and have been shown to suppress intake of certain foods. The combination of these drugs has shown to be more effective in reducing alcohol consumption than either drug alone. The present study assessed the effects of naltrexone and baclofen, alone and in combination, on intake of foods comprised of various macronutrients. Male Sprague-Dawley rats were given 12-hr daily access to chow and a fat emulsion, sugar-fat emulsion, or a sugar solution for 21 days. Rats were then administered (intraperitoneal) baclofen-naltrexone combinations (0.1 mg/kg naltrexone and 1.0 mg/kg baclofen, 1.0 mg/kg naltrexone and 1.8 mg/kg baclofen), and naltrexone (0.1, 1.0 mg/kg) and baclofen (1.0, 1.8 mg/kg) alone. The high dose of the baclofen-naltrexone combination reduced palatable food intake in both the fat and sugar-fat groups compared with vehicle, without affecting chow consumption in these groups. Naltrexone showed little significant effects on intake of either palatable food or chow. Baclofen also reduced palatable food intake in the fat and fat-sugar groups, but differences were only noted between the low and high dose. The combination of baclofen and naltrexone may be a useful tool in selectively targeting the consumption of high-fat and sugar- and fat-rich foods. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  17. The Mixed Opioid Receptor Antagonist Naltrexone Mitigates Stimulant-Induced Euphoria: A Double-Blind, Placebo-Controlled Trial of Naltrexone.

    PubMed

    Spencer, Thomas J; Bhide, Pradeep; Zhu, Jinmin; Faraone, Stephen V; Fitzgerald, Maura; Yule, Amy M; Uchida, Mai; Spencer, Andrea E; Hall, Anna M; Koster, Ariana J; Feinberg, Leah; Kassabian, Sarah; Storch, Barbara; Biederman, Joseph

    Supratherapeutic doses of methylphenidate activate μ-opioid receptors, which are linked to euphoria. This study assessed whether naltrexone, a mixed μ-opioid antagonist, may attenuate the euphoric effects of stimulants, thereby minimizing their abuse potential in subjects with attention-deficit/hyperactivity disorder (ADHD). We conducted a 6-week, double-blind, placebo-controlled, randomized clinical trial of naltrexone in adults with DSM-IV ADHD receiving open treatment with a long-acting formulation of methylphenidate (January 2013 to June 2015). Spheroidal Oral Drug Absorption System methylphenidate (SODAS-MPH) was administered twice daily, was titrated to ~1 mg/kg/d over 3 weeks, and was continued for 3 additional weeks depending on response and adverse effects. Subjects were adults with ADHD preselected for having experienced euphoria with an oral test dose of 60 mg of immediate-release methylphenidate (IR-MPH). The primary outcome measure was Question 2 (Liking a Drug Effect) on the Drug Rating Questionnaire, Subject version, which was assessed after oral test doses of 60 mg of IR-MPH were administered after the third and sixth weeks of treatment with SODAS-MPH. Thirty-seven subjects who experienced stimulant-induced (mild) euphoria at a baseline visit were started in the open trial of SODAS-MPH and randomized to naltrexone 50 mg/d or placebo. Thirty-one subjects completed through week 3, and 25 completed through week 6. Naltrexone significantly diminished the euphoric effect of IR-MPH during the heightened-risk titration phase (primary outcome; first 3 weeks) (χ² = 5.07, P = .02) but not the maintenance phase (weeks 4-6) (χ² = 0.22, P = .64) of SODAS-MPH treatment. Preclinical findings are extended to humans showing that naltrexone may mitigate stimulant-associated euphoria. Our findings provide support for further studies combining opioid receptor antagonists with stimulants to reduce abuse potential. ClinicalTrials.gov identifier: NCT01673594.

  18. Drug safety evaluation of naltrexone/bupropion for the treatment of obesity.

    PubMed

    Verpeut, Jessica L; Bello, Nicholas T

    2014-06-01

    Obesity is a known health risk for the development of several preventable diseases. Obesity-related metabolic alterations negatively impact different physiological mechanisms, which supports the rationale for the use of combined drug therapy. Naltrexone is an opioid antagonist for the treatment of opioid and alcohol dependency, whereas bupropion is a norepinephrine/dopamine reuptake inhibitor used to treat depression and smoking cessation. Although not effective as individual monotherapies for obesity, naltrexone and bupropion in combination produce weight loss and a metabolic profile beneficial for the potential treatment of obesity. This review examines the safety and antiobesity effects of naltrexone and bupropion alone and in combination. It reviews the results of four Phase III clinical trials of a novel fixed dose of sustained-released naltrexone/bupropion. Naltrexone/bupropion has a greater weight loss efficacy than two FDA-approved medications, orlistat and lorcaserin. Although the weight loss produced by phentermine/topiramate is superior to naltrexone/bupropion, the safety profile of naltrexone/bupropion has less severe adverse effects. In addition, naltrexone/bupropion is well tolerated, with nausea being the most reported adverse event. Unlike other centrally acting medications, lorcaserin and phentermine/topiramate, naltrexone/bupropion has no abuse potential.

  19. Revisiting the ALA/N (alpha-lipoic acid/low-dose naltrexone) protocol for people with metastatic and nonmetastatic pancreatic cancer: a report of 3 new cases.

    PubMed

    Berkson, Burton M; Rubin, Daniel M; Berkson, Arthur J

    2009-12-01

    The authors, in a previous article, described the long-term survival of a man with pancreatic cancer and metastases to the liver, treated with intravenous alpha-lipoic acid and oral low-dose naltrexone (ALA/N) without any adverse effects. He is alive and well 78 months after initial presentation. Three additional pancreatic cancer case studies are presented in this article. At the time of this writing, the first patient, GB, is alive and well 39 months after presenting with adenocarcinoma of the pancreas with metastases to the liver. The second patient, JK, who presented to the clinic with the same diagnosis was treated with the ALA/N protocol and after 5 months of therapy, PET scan demonstrated no evidence of disease. The third patient, RC, in addition to his pancreatic cancer with liver and retroperitoneal metastases, has a history of B-cell lymphoma and prostate adenocarcinoma. After 4 months of the ALA/N protocol his PET scan demonstrated no signs of cancer. In this article, the authors discuss the poly activity of ALA: as an agent that reduces oxidative stress, its ability to stabilize NF(k)B, its ability to stimulate pro-oxidant apoptosic activity, and its discriminative ability to discourage the proliferation of malignant cells. In addition, the ability of lowdose naltrexone to modulate an endogenous immune response is discussed. This is the second article published on the ALA/N protocol and the authors believe the protocol warrants clinical trial.

  20. Pharmacodynamic Profile of Tramadol in Humans: Influence of Naltrexone Pretreatment

    PubMed Central

    Stoops, William W.; Lofwall, Michelle R.; Nuzzo, Paul A.; Craig, Lori B.; Siegel, Anthony J.; Walsh, Sharon L.

    2012-01-01

    Rationale Tramadol is a prescription analgesic that activates mu opioid and monoamine receptor systems. Tramadol is thought to have limited abuse potential compared to mu opioid agonists, but laboratory data indicate that it shares some of their pharmacodynamic effects. Objectives This study evaluated the effect of mu opioid receptor blockade with naltrexone on the pharmacodynamic action of tramadol in humans. Methods This inpatient, double-blind, randomized, within-subject study examined the effects of oral placebo, tramadol (87.5, 175 and 350 mg) and hydromorphone (4 and 16 mg; positive control) after 1 hr pretreatment with oral naltrexone (0 and 50 mg). Ten recreational opioid users completed the study. Pharmacodynamic effects were measured before and for 7 hr after initial drug administration. Results Lower doses of tramadol and hydromorphone were generally placebo-like. Hydromorphone (16 mg) produced prototypic mu opioid agonist-like effects that were blocked by naltrexone. Tramadol (350 mg) produced miosis and increased ratings of “Good Effects” and “Liking ,” but also increased ratings of “Bad Effects.” Naltrexone reversed tramadol-induced physiological effects and mydriasis emerged, but unlike results with hydromorphone, naltrexone only partially attenuated tramadol’s positive subjective effects and actually enhanced several unpleasant subjective ratings. Conclusions Naltrexone can be used to disentangle the mixed neuropharmacological actions of tramadol. High dose tramadol produces a mixed profile of effects. These data suggest that both mu and non-mu opioid actions play a role in tramadol’s subjective profile of action. PMID:22623016

  1. Randomized, proof-of-concept trial of low dose naltrexone for patients with breakthrough symptoms of major depressive disorder on antidepressants.

    PubMed

    Mischoulon, David; Hylek, Lindsay; Yeung, Albert S; Clain, Alisabet J; Baer, Lee; Cusin, Cristina; Ionescu, Dawn Flosnik; Alpert, Jonathan E; Fava, Maurizio; Soskin, David P

    2017-01-15

    Given the proposed dopaminergic mechanism of low-dose naltrexone (LDN), we examined its efficacy as augmentation for depressive breakthrough on pro-dopaminergic antidepressant regimens. 12 adults (67% female, mean age = 45±12) with recurrent DSM-IV major depressive disorder (MDD) on dopaminergic antidepressant regimens (stimulants, dopamine agonists, bupropion [≥300mg/day], aripiprazole [≤2.5mg/day], or sertraline [≥150mg/day]) were randomized to naltrexone 1mg b.i.d. (n=6) or placebo (n=6) augmentation for 3 weeks. All subjects completed the trial. Hamilton Depression Rating Scale (HAM-D-17) scores (primary outcome measure) decreased from 21.2±2.0 to 11.7±7.7 for LDN, from 23.7±2.3 to 17.8±5.9 for placebo (Cohen's d=0.62; p=0.3 between treatment groups). HAM-D-28 scores decreased from 26.2±4.0 to 12.0±9.8 for LDN, from 26.3±2.6 to 19.8±6.6 for placebo (d=1.15; p=0.097). Montgomery-Asberg Depression Rating Scale (MADRS-10 item) scores decreased from 30.4±4.9 to 12.2±8.4 for LDN, from 30.7±4.3 to 22.8±8.5) for placebo (d=1.45; p=0.035). MADRS-15 item scores decreased from 36.6±6.2 to 13.2±8.8 for LDN, from 36.7±4.2 to 26.0±10.0 for placebo (d=1.49; p=0.035). Clinical Global Improvement Scale-Severity (CGI-S) scores decreased from 4.3±0.5 to 3.0±1.1 for LDN, from 4.3±0.5 to 4.0±0.6 for placebo (d=1.22; p=0.064). Small study; restrictions on allowed antidepressants. LDN augmentation showed some benefit for MDD relapse on dopaminergic agents. Confirmation in larger studies is needed. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Opioid Detoxification and Naltrexone Induction Strategies: Recommendations for Clinical Practice

    PubMed Central

    Sigmon, Stacey C.; Bisaga, Adam; Nunes, Edward V.; O'Connor, Patrick G.; Kosten, Thomas; Woody, George

    2015-01-01

    Background Opioid dependence is a significant public health problem associated with high risk for relapse if treatment is not ongoing. While maintenance on opioid agonists (i.e., methadone, buprenorphine) often produces favorable outcomes, detoxification followed by treatment with the μ-opioid receptor antagonist naltrexone may offer a potentially useful alternative to agonist maintenance for some patients. Method Treatment approaches for making this transition are described here based on a literature review and solicitation of opinions from several expert clinicians and scientists regarding patient selection, level of care, and detoxification strategies. Conclusion Among the current detoxification regimens, the available clinical and scientific data suggest that the best approach may be using an initial 2–4 mg dose of buprenorphine combined with clonidine, other ancillary medications, and progressively increasing doses of oral naltrexone over 3–5 days up to the target dose of naltrexone. However, more research is needed to empirically validate the best approach for making this transition. PMID:22404717

  3. Combination of Levo-Tetrahydropalmatine and Low Dose Naltrexone: A Promising Treatment for Prevention of Cocaine Relapse.

    PubMed

    Sushchyk, Sarah; Xi, Zheng-Xiong; Wang, Jia Bei

    2016-05-01

    Relapse to drug use is often cited as the major obstacle in overcoming a drug addiction. Whereas relapse can occur for a myriad of reasons, it is well established that complex neuroadaptations that occur over the course of addiction are major factors. Cocaine, as a potent dopamine transporter blocker, specifically induces alterations in the dopaminergic as well as other monoaminergic neurotransmissions, which lead to cocaine abuse and dependence. Evidence also suggests that adaptations in the endogenous opioids play important roles in pathophysiology of cocaine addiction. Following this evidence, we investigated a combination medication, levo-tetrahydropalmatine (l-THP) and low dose naltrexone (LDN), targeting primarily dopaminergic and endogenous opioid systems as a cocaine-relapse-prevention treatment. In the present study Wistar rats were used to assess the effects ofl-THP and LDN on cocaine self-administration, drug-seeking behavior during cocaine reinstatement, spontaneous locomotion, and effects on the endogenous opioid system. We determined that the combination ofl-THP and LDN reduces drug-seeking behavior during reinstatement more potently thanl-THP alone. Additionally, the combination ofl-THP and LDN attenuates the sedative locomotor effect induced byl-THP. Furthermore, we revealed that treatment with the combination ofl-THP and LDN has an upregulatory effect on both plasmaβ-endorphin and hypothalamic POMC that was not observed inl-THP-treated groups. These results suggest that the combination ofl-THP and LDN has great potential as an effective and well-tolerated medication for cocaine relapse prevention. U.S. Government work not protected by U.S. copyright.

  4. Combination of Levo-Tetrahydropalmatine and Low Dose Naltrexone: A Promising Treatment for Prevention of Cocaine Relapse

    PubMed Central

    Sushchyk, Sarah; Xi, Zheng-Xiong

    2016-01-01

    Relapse to drug use is often cited as the major obstacle in overcoming a drug addiction. Whereas relapse can occur for a myriad of reasons, it is well established that complex neuroadaptations that occur over the course of addiction are major factors. Cocaine, as a potent dopamine transporter blocker, specifically induces alterations in the dopaminergic as well as other monoaminergic neurotransmissions, which lead to cocaine abuse and dependence. Evidence also suggests that adaptations in the endogenous opioids play important roles in pathophysiology of cocaine addiction. Following this evidence, we investigated a combination medication, levo-tetrahydropalmatine (l-THP) and low dose naltrexone (LDN), targeting primarily dopaminergic and endogenous opioid systems as a cocaine-relapse-prevention treatment. In the present study Wistar rats were used to assess the effects of l-THP and LDN on cocaine self-administration, drug-seeking behavior during cocaine reinstatement, spontaneous locomotion, and effects on the endogenous opioid system. We determined that the combination of l-THP and LDN reduces drug-seeking behavior during reinstatement more potently than l-THP alone. Additionally, the combination of l-THP and LDN attenuates the sedative locomotor effect induced by l-THP. Furthermore, we revealed that treatment with the combination of l-THP and LDN has an upregulatory effect on both plasma β-endorphin and hypothalamic POMC that was not observed in l-THP-treated groups. These results suggest that the combination of l-THP and LDN has great potential as an effective and well-tolerated medication for cocaine relapse prevention. PMID:26903543

  5. Ultra-low dose of Mycobacterium tuberculosis aerosol creates partial infection in mice.

    PubMed

    Saini, Divey; Hopkins, Gregory W; Seay, Sarah A; Chen, Ching-Ju; Perley, Casey C; Click, Eva M; Frothingham, Richard

    2012-03-01

    A murine low dose (LD) aerosol model is commonly used to test tuberculosis vaccines. Doses of 50-400 CFU (24h lung CFU) infect 100% of exposed mice. The LD model measures progression from infection to disease based on organ CFU at defined time points. To mimic natural exposure, we exposed mice to an ultra-low dose (ULD) aerosol. We estimated the presented dose by sampling the aerosol. Female C57BL/6 mice were exposed to Mycobacterium tuberculosis H37Rv aerosol at 1.0, 1.1, 1.6, 5.4, and 11 CFU presented dose, infecting 27%, 36%, 36%, 100%, and 95% of mice, respectively. These data are compatible with a stochastic infection event (Poisson distribution, weighted R(2)=0.97) or with a dose-response relationship (sigmoid distribution, weighted R(2)=0.97). Based on the later assumption, the ID50 was 1.6CFU presented dose (95% confidence interval, 1.2-2.1). We compared organ CFU after ULD and LD aerosols (5.4 vs. 395CFU presented dose). Lung burden was 30-fold lower in the ULD model at 4 weeks (3.4 vs. 4.8 logs, p<0.001) and 18 weeks (≤3.6 vs. 5.0 logs, p=0.01). Mice exposed to ULD aerosols as compared to LD aerosols had greater within-group CFU variability. Exposure to ULD aerosols leads to infection in a subset of mice, and to persistently low organ CFU. The ULD aerosol model may resemble human pulmonary tuberculosis more closely than the standard LD model, and may be used to identify host or bacterial factors that modulate the initial infection event. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Naltrexone for the treatment of comorbid tobacco and pornography addiction.

    PubMed

    Capurso, Noah A

    2017-03-01

    Co-occurring addictive disorders are common, however treatment strategies for this population have not been extensively studied. This is especially the case for behavioral addictions. We present a patient (N = 1) with tobacco use disorder and problematic pornography use treated with naltrexone. Naltrexone treatment resulted in a decrease in pornography viewing and cigarette smoking, however had the adverse effect of anhedonia. A lower dose modestly impacted pornography viewing but not smoking. Relevant literature regarding co-occurring addictions as well as use of naltrexone is reviewed. This report represents the first case of tobacco and pornography co-addiction in the literature and supports the assertion that treatment of one addictive disorder can benefit another in the dually addicted patient. The efficacy of naltrexone for smoking is notable as previous studies of naltrexone in smoking have been disappointing. This case suggests future treatment strategies for comorbid addictions. (Am J Addict 2017;26:115-117). © 2017 American Academy of Addiction Psychiatry.

  7. Gender differences in treatment and clinical characteristics among patients receiving extended release naltrexone.

    PubMed

    Herbeck, Diane M; Jeter, Kira E; Cousins, Sarah J; Abdelmaksoud, Reham; Crèvecoeur-MacPhail, Desirée

    2016-01-01

    Further research is needed to investigate real-world acceptability of extended-release naltrexone for alcohol and opioid use disorders, and potential gender differences. This study examines treatment and clinical characteristics among men and women receiving extended-release naltrexone in a large, publicly funded substance use disorder treatment system (N = 465; 52% female). Patient demographics, treatment characteristics, and the number of extended-release naltrexone doses received were collected from administrative data and treatment program staff. Additionally, patients provided information on experiences with extended-release naltrexone in an open-ended format at 1, 2, and 3 weeks following their first injection. For a subsample of patients (N = 220), alcohol/opioid cravings and specific adverse effects were also assessed. Compared to men, women reported experiencing a higher rate and mean number of adverse effects. Overall, craving scores showed substantial reductions over time. However, among patients taking extended-release naltrexone for alcohol use, women showed a significantly greater reduction in craving scores compared to men. No gender differences were observed in the number of extended-release naltrexone doses received. Although women may have a greater need for additional support in managing early adverse effects, extended-release naltrexone as an adjunct to psychosocial treatment may be an acceptable and promising treatment approach for both men and women, and particularly for women prescribed extended-release naltrexone for alcohol use. This study contributes further information on patients' experiences during the early course of extended-release naltrexone treatment in real-world settings. Understanding these experiences may assist policy makers and treatment providers in addressing challenges of implementing this treatment into wider practice.

  8. Injectable, sustained-release naltrexone for the treatment of opioid dependence: a randomized, placebo-controlled trial

    PubMed Central

    Comer, Sandra D.; Sullivan, Maria A.; Yu, Elmer; Rothenberg, Jami L.; Kleber, Herbert D.; Kampman, Kyle; Dackis, Charles; O'Brien, Charles P.; Chiang, C. Nora; Hawks, Richard L.

    2013-01-01

    Context Naltrexone is a medication available in oral form that can completely block the effects produced by opioid agonists, such as heroin. However, poor medication compliance with naltrexone has been a major obstacle to the effective treatment of opioid dependence. Objective To evaluate the safety and efficacy of a sustained-release depot formulation of naltrexone in treating opioid dependence. Design, Setting, and Participants Randomized, double-blind, placebo-controlled, 8-week multi-center trial of male and female heroin-dependent patients who participated in the study between September 2000 and November 2003. Participants were stratified by years of heroin use (≥5, <4.9) and gender, and then randomized to receive one of three doses: placebo, 192 mg, or 384 mg depot naltrexone. Doses were administered at the beginning of Week 1 and then again four weeks later at the beginning of Week 5. All participants received twice-weekly relapse prevention therapy, provided observed urine samples, and completed other assessments at each visit. Main Outcome Measures Primary outcome measures were retention in treatment and percentage of opioid-negative urine samples. Results A total of 60 patients were randomized at two centers. Retention in treatment was dose related with 39%, 60%, and 68% of the patients in the placebo, naltrexone 192 mg, and naltrexone 384 mg groups, respectively, remaining in treatment at the end of the two-month treatment period. Analysis of the time to dropout revealed a significant main effect of dose with mean time to dropout of 27, 36, and 48 days, respectively, for the placebo, naltrexone 192 mg, and naltrexone 384 mg groups. The percentage of urine samples negative for opioids varied significantly as a function of dose, as did the percentage of urine samples negative for methadone, cocaine, benzodiazepines, and amphetamine. The percentage of urine samples negative for cannabinoids was not significantly different across groups. When the data were

  9. Potential Treatment of Inflammatory and Proliferative Diseases by Ultra-Low Doses of Ionizing Radiations

    PubMed Central

    Sanders, Charles L.

    2012-01-01

    Ultra-low doses and dose- rates of ionizing radiation are effective in preventing disease which suggests that they also may be effective in treating disease. Limited experimental and anecdotal evidence indicates that low radiation doses from radon in mines and spas, thorium-bearing monazite sands and enhanced radioactive uranium ore obtained from a natural geological reactor may be useful in treating many inflammatory conditions and proliferative disorders, including cancer. Optimal therapeutic applications were identified via a literature survey as dose-rates ranging from 7 to 11μGy/hr or 28 to 44 times world average background rates. Rocks from an abandoned uranium mine in Utah were considered for therapeutic application and were examined by γ-ray and laser-induced breakdown fluorescence spectroscopy. The rocks showed the presence of transuranics and fission products with a γ-ray energy profile similar to aged spent uranium nuclear fuel (93% dose due to β particles and 7% due to γ rays). Mud packs of pulverized uranium ore rock dust in sealed plastic bags delivering bag surface β,γ dose-rates of 10–450 μGy/h were used with apparent success to treat several inflammatory and proliferative conditions in humans. PMID:23304108

  10. CORK Study in Cystic Fibrosis: Sustained Improvements in Ultra-Low-Dose Chest CT Scores After CFTR Modulation With Ivacaftor.

    PubMed

    Ronan, Nicola J; Einarsson, Gisli G; Twomey, Maria; Mooney, Denver; Mullane, David; NiChroinin, Muireann; O'Callaghan, Grace; Shanahan, Fergus; Murphy, Desmond M; O'Connor, Owen J; Shortt, Cathy A; Tunney, Michael M; Eustace, Joseph A; Maher, Michael M; Elborn, J Stuart; Plant, Barry J

    2018-02-01

    Ivacaftor produces significant clinical benefit in patients with cystic fibrosis (CF) with the G551D mutation. Prevalence of this mutation at the Cork CF Centre is 23%. This study assessed the impact of cystic fibrosis transmembrane conductance regulator modulation on multiple modalities of patient assessment. Thirty-three patients with the G551D mutation were assessed at baseline and prospectively every 3 months for 1 year after initiation of ivacaftor. Change in ultra-low-dose chest CT scans, blood inflammatory mediators, and the sputum microbiome were assessed. Significant improvements in FEV 1 , BMI, and sweat chloride levels were observed post-ivacaftor treatment. Improvement in ultra-low-dose CT imaging scores were observed after treatment, with significant mean reductions in total Bhalla score (P < .01), peribronchial thickening (P = .035), and extent of mucous plugging (P < .001). Reductions in circulating inflammatory markers, including interleukin (IL)-1β, IL-6, and IL-8 were demonstrated. There was a 30% reduction in the relative abundance of Pseudomonas species and an increase in the relative abundance of bacteria associated with more stable community structures. Posttreatment community richness increased significantly (P = .03). Early and sustained improvements on ultra-low-dose CT scores suggest it may be a useful method of evaluating treatment response. It paralleled improvement in symptoms, circulating inflammatory markers, and changes in the lung microbiota. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  11. Effects of incentives for naltrexone adherence on opiate abstinence in heroin-dependent adults

    PubMed Central

    Jarvis, Brantley P.; Holtyn, August F.; DeFulio, Anthony; Dunn, Kelly E.; Everly, Jeffrey J.; Leoutsakos, Jeannie-Marie S.; Umbricht, Annie; Fingerhood, Michael; Bigelow, George E.; Silverman, Kenneth

    2017-01-01

    Aim To test whether an incentive-based intervention that increased adherence to naltrexone also increased opiate abstinence. Design Post-hoc combined analysis of three earlier randomized controlled trials that individually showed that incentives for adherence to oral and to extended-release injection naltrexone dosing schedules increased naltrexone adherence but not opiate abstinence. Setting Outpatient therapeutic workplace in Baltimore, MD, USA. Participants 140 unemployed heroin-dependent adults participating from 2006–2010. Interventions Participants were hired in a model workplace for 26 weeks and randomized to a Contingency (n=72) or Prescription (n=68) group. Both groups were offered naltrexone. Contingency participants were required to take scheduled doses of naltrexone in order to work and earn wages. Prescription participants could earn wages independent of naltrexone adherence. Measures Thrice-weekly and monthly urine samples tested for opiates and cocaine and measures of naltrexone adherence (percentage of monthly urine samples positive for naltrexone or percentage of scheduled injections received). All analyses included prerandomization attendance, opiate use, and cocaine use as covariates. Additional analyses controlled for cocaine use and naltrexone adherence during the intervention. Findings Contingency participants had more opiate abstinence than Prescription participants (68.1% vs. 52.9% opiate-negative thrice-weekly urine samples, respectively; and 71.9% vs. 61.7% opiate-negative monthly urine samples, respectively) based on initial analyses (thrice-weekly samples, OR = 3.3, 95% CI = 1.7–6.5, p < .01; monthly samples, OR = 2.6, 95% CI = 1.0–7.1, p = .06) and on analyses that controlled for cocaine use (thrice-weekly samples, OR = 3.9, 95% CI = 3.3–4.5, p < .01; monthly samples, OR = 3.4, 95% CI = 1.1–11.1, p =.04), which was high and associated with opiate use. The difference in opiate abstinence rates between Contingency participants

  12. Combined administration of buprenorphine and naltrexone produces antidepressant-like effects in mice

    PubMed Central

    Almatroudi, Abdulrahman; Husbands, Stephen M.; Bailey, Christopher P.; Bailey, Sarah J.

    2016-01-01

    Opiates have been used historically for the treatment of depression. Renewed interest in the use of opiates as antidepressants has focussed on the development of kappa opioid receptor (κ-receptor) antagonists. Buprenorphine acts as a partial μ-opioid receptor agonist and a κ-receptor antagonist. By combining buprenorphine with the opioid antagonist naltrexone, the activation of μ-opioid receptors would be reduced and the κ-antagonist properties enhanced. We have established that a combination dose of buprenorphine (1mg/kg) with naltrexone (1mg/kg) functions as a short-acting κ-antagonist in the mouse tail withdrawal test. Furthermore, this dose combination is neither rewarding nor aversive in the conditioned place preference paradigm and is without significant locomotor effects. We have shown for the first time that systemic co-administration of buprenorphine (1mg/kg) with naltrexone (1mg/kg) in CD-1 mice produced significant antidepressant-like responses in behaviours in both the forced swim test and novelty induced hypophagia task. Behaviours in the elevated plus maze and light dark box were not significantly altered by treatment with buprenorphine alone, or in combination with naltrexone. We propose that the combination of buprenorphine with naltrexone represents a novel, and potentially a readily translatable approach, to the treatment of depression. PMID:26045511

  13. A BMI-adjusted ultra-low-dose CT angiography protocol for the peripheral arteries-Image quality, diagnostic accuracy and radiation exposure.

    PubMed

    Schreiner, Markus M; Platzgummer, Hannes; Unterhumer, Sylvia; Weber, Michael; Mistelbauer, Gabriel; Loewe, Christian; Schernthaner, Ruediger E

    2017-08-01

    To investigate radiation exposure, objective image quality, and the diagnostic accuracy of a BMI-adjusted ultra-low-dose CT angiography (CTA) protocol for the assessment of peripheral arterial disease (PAD), with digital subtraction angiography (DSA) as the standard of reference. In this prospective, IRB-approved study, 40 PAD patients (30 male, mean age 72 years) underwent CTA on a dual-source CT scanner at 80kV tube voltage. The reference amplitude for tube current modulation was personalized based on the body mass index (BMI) with 120 mAs for [BMI≤25] or 150 mAs for [2570%) was assessed by two readers independently and compared to subsequent DSA. Radiation exposure was assessed with the computed tomography dose index (CTDIvol) and the dosis-length product (DLP). Objective image quality was assessed via contrast- and signal-to-noise ratio (CNR and SNR) measurements. Radiation exposure and image quality were compared between the BMI groups and between the BMI-adjusted ultra-low-dose protocol and the low-dose institutional standard protocol (ISP). The BMI-adjusted ultra-low-dose protocol reached high diagnostic accuracy values of 94% for Reader 1 and 93% for Reader 2. Moreover, in comparison to the ISP, it showed significantly (p<0.001) lower CTDIvol (1.97±0.55mGy vs. 4.18±0.62 mGy) and DLP (256±81mGy x cm vs. 544±83mGy x cm) but similar image quality (p=0.37 for CNR). Furthermore, image quality was similar between BMI groups (p=0.86 for CNR). A CT protocol that incorporates low kV settings with a personalized (BMI-adjusted) reference amplitude for tube current modulation and iterative reconstruction enables very low radiation exposure CTA, while maintaining good image quality and high diagnostic accuracy in the assessment of PAD. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. The mesolimbic system participates in the naltrexone-induced reversal of sexual exhaustion: opposite effects of intra-VTA naltrexone administration on copulation of sexually experienced and sexually exhausted male rats.

    PubMed

    Garduño-Gutiérrez, René; León-Olea, Martha; Rodríguez-Manzo, Gabriela

    2013-11-01

    Male rats allowed to copulate until reaching sexual exhaustion exhibit a long-lasting sexual behavior inhibition (around 72 h) that can be reversed by systemic opioid receptor antagonist administration. Copulation activates the mesolimbic dopaminergic system (MLS) and promotes endogenous opioid release. In addition, endogenous opioids, acting at the ventral tegmental area (VTA), modulate the activity of the MLS. We hypothesized that endogenous opioids participate in the sexual exhaustion phenomenon by interacting with VTA opioid receptors and consequently, its reversal by opioid antagonists could be exerted at those receptors. In this study we determined the effects of intra-VTA infusion of different doses of the non-specific opioid receptor antagonist naltrexone (0.1-1.0 μg/rat) on the already established sexual behavior inhibition of sexually exhausted male rats. To elucidate the possible involvement of VTA δ-opioid receptors in the naltrexone-mediated reversal of sexual exhaustion, the effects of different doses of the selective δ-opioid receptor antagonist, naltrindole (0.03-1.0 μg/rat) were also tested. Results showed that intra-VTA injection of 0.3 μg naltrexone reversed the sexual inhibition of sexually exhausted rats, evidenced by an increased percentage of animals capable of showing two successive ejaculations. Intra-VTA infused naltrindole did not reverse sexual exhaustion at any dose. It is concluded that the MLS is involved in the reversal of sexual exhaustion induced by systemic naltrexone, and that μ-, but not δ-opioid receptors participate in this effect. Intra-VTA naltrexone infusion to sexually experienced male rats had an inhibitory effect on sexual activity. The opposite effects of intra-VTA naltrexone on male rat sexual behavior expression of sexually experienced and sexually exhausted rats is discussed. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Naltrexone Reverses Ethanol Preference and Protein Kinase C Activation in Drosophila melanogaster

    PubMed Central

    Koyyada, Rajeswari; Latchooman, Nilesh; Jonaitis, Julius; Ayoub, Samir S.; Corcoran, Olivia; Casalotti, Stefano O.

    2018-01-01

    Alcohol use disorder (AUD) is a major health, social and economic problem for which there are few effective treatments. The opiate antagonist naltrexone is currently prescribed clinically with mixed success. We have used naltrexone in an established behavioral assay (CAFE) in Drosophila melanogaster that measures the flies' preference for ethanol-containing food. We have confirmed that Drosophila exposed to ethanol develop a preference toward this drug and we demonstrate that naltrexone, in a dose dependant manner, reverses the ethanol-induced ethanol preference. This effect is not permanent, as preference for alcohol returns after discontinuing naltrexone. Additionally, naltrexone reduced the alcohol-induced increase in protein kinase C activity. These findings are of interest because they confirm that Drosophila is a useful model for studying human responses to addictive drugs. Additionally because of the lack of a closely conserved opiate system in insects, our results could either indicate that a functionally related system does exist in insects or that in insects, and potentially also in mammals, naltrexone binds to alternative sites. Identifying such sites could lead to improved treatment strategies for AUD. PMID:29593550

  16. Investigation of ultra low-dose scans in the context of quantum-counting clinical CT

    NASA Astrophysics Data System (ADS)

    Weidinger, T.; Buzug, T. M.; Flohr, T.; Fung, G. S. K.; Kappler, S.; Stierstorfer, K.; Tsui, B. M. W.

    2012-03-01

    In clinical computed tomography (CT), images from patient examinations taken with conventional scanners exhibit noise characteristics governed by electronics noise, when scanning strongly attenuating obese patients or with an ultra-low X-ray dose. Unlike CT systems based on energy integrating detectors, a system with a quantum counting detector does not suffer from this drawback. Instead, the noise from the electronics mainly affects the spectral resolution of these detectors. Therefore, it does not contribute to the image noise in spectrally non-resolved CT images. This promises improved image quality due to image noise reduction in scans obtained from clinical CT examinations with lowest X-ray tube currents or obese patients. To quantify the benefits of quantum counting detectors in clinical CT we have carried out an extensive simulation study of the complete scanning and reconstruction process for both kinds of detectors. The simulation chain encompasses modeling of the X-ray source, beam attenuation in the patient, and calculation of the detector response. Moreover, in each case the subsequent image preprocessing and reconstruction is modeled as well. The simulation-based, theoretical evaluation is validated by experiments with a novel prototype quantum counting system and a Siemens Definition Flash scanner with a conventional energy integrating CT detector. We demonstrate and quantify the improvement from image noise reduction achievable with quantum counting techniques in CT examinations with ultra-low X-ray dose and strong attenuation.

  17. Usefulness of model-based iterative reconstruction in semi-automatic volumetry for ground-glass nodules at ultra-low-dose CT: a phantom study.

    PubMed

    Maruyama, Shuki; Fukushima, Yasuhiro; Miyamae, Yuta; Koizumi, Koji

    2018-06-01

    This study aimed to investigate the effects of parameter presets of the forward projected model-based iterative reconstruction solution (FIRST) on the accuracy of pulmonary nodule volume measurement. A torso phantom with simulated nodules [diameter: 5, 8, 10, and 12 mm; computed tomography (CT) density: - 630 HU] was scanned with a multi-detector CT at tube currents of 10 mA (ultra-low-dose: UL-dose) and 270 mA (standard-dose: Std-dose). Images were reconstructed with filtered back projection [FBP; standard (Std-FBP), ultra-low-dose (UL-FBP)], FIRST Lung (UL-Lung), and FIRST Body (UL-Body), and analyzed with a semi-automatic software. The error in the volume measurement was determined. The errors with UL-Lung and UL-Body were smaller than that with UL-FBP. The smallest error was 5.8% ± 0.3 for the 12-mm nodule with UL-Body (middle lung). Our results indicated that FIRST Body would be superior to FIRST Lung in terms of accuracy of nodule measurement with UL-dose CT.

  18. Maternally Administered Sustained-Release Naltrexone in Rats Affects Offspring Neurochemistry and Behaviour in Adulthood

    PubMed Central

    Krstew, Elena V.; Tait, Robert J.; Hulse, Gary K.

    2012-01-01

    Naltrexone is not recommended during pregnancy. However, sustained-release naltrexone implant use in humans has resulted in cases of inadvertent foetal exposure. Here, we used clinically relevant dosing to examine the effects of maternally administered sustained-release naltrexone on the rat brain by examining offspring at birth and in adulthood. Maternal treatment (naltrexone or placebo implant) started before conception and ceased during gestation, birth or weaning. Morphometry was assessed in offspring at birth and adulthood. Adult offspring were evaluated for differences in locomotor behaviour (basal and morphine-induced, 10 mg/kg, s.c.) and opioid neurochemistry, propensity to self-administer morphine and cue-induced drug-seeking after abstinence. Blood analysis confirmed offspring exposure to naltrexone during gestation, birth and weaning. Naltrexone exposure increased litter size and reduced offspring birth-weight but did not alter brain morphometry. Compared to placebo, basal motor activity of naltrexone-exposed adult offspring was lower, yet they showed enhanced development of psychomotor sensitization to morphine. Developmental naltrexone exposure was associated with resistance to morphine-induced down-regulation of striatal preproenkephalin mRNA expression in adulthood. Adult offspring also exhibited greater operant responding for morphine and, in addition, cue-induced drug-seeking was enhanced. Collectively, these data show pronounced effects of developmental naltrexone exposure, some of which persist into adulthood, highlighting the need for follow up of humans that were exposed to naltrexone in utero. PMID:23300784

  19. The Combination Very Low-Dose Naltrexone–Clonidine in the Management of Opioid Withdrawal

    PubMed Central

    Mannelli, Paolo; Peindl, Kathleen; Wu, Li-Tzy; Patkar, Ashwin A.; Gorelick, David A.

    2013-01-01

    Background The management of withdrawal absorbs substantial clinical efforts in opioid dependence (OD). The real challenge lies in improving current pharmacotherapies. Although widely used, clonidine causes problematic adverse effects and does not alleviate important symptoms of opioid withdrawal, alone or in combination with the opioid antagonist naltrexone. Very low-dose naltrexone (VLNTX) has been shown to attenuate withdrawal intensity and noradrenaline release following opioid agonist taper, suggesting a combination with clonidine may result in improved safety and efficacy. Objectives We investigated the effects of a VLNTX–clonidine combination in a secondary analysis of data from a double-blind, randomized opioid detoxification trial. Methods Withdrawal symptoms and treatment completion were compared following VLNTX (.125 or .25 mg/day) and clonidine (.1–.2 mg q6h) in 127 individuals with OD undergoing 6-day methadone inpatient taper at a community program. Results VLNTX was more effective than placebo or clonidine in reducing symptoms and signs of withdrawal. The use of VLNTX in combination with clonidine was associated with attenuated subjective withdrawal compared with each medication alone, favoring detoxification completion in comparison with clonidine or naltrexone placebo. VLNTX/clonidine was effective in reducing symptoms that are both undertreated and well controlled with clonidine treatment and was not associated with significant adverse events compared with other treatments. Conclusions and Scientific Significance Preliminary results elucidate neurobiological mechanisms of OD and support the utility of controlled studies on a novel VLNTX + low-dose clonidine combination for the management of opioid withdrawal. PMID:22233189

  20. Naltrexone in organic bulimia: a preliminary report.

    PubMed

    Childs, A

    1987-01-01

    Multiple lines of experimental evidence point to the involvement of endogenous opiates in appetite regulation. Post brain injury patients often exhibit driven eating behaviour. Since this problem fails to respond to behaviour modification, appetite suppressants, lithium, or any other usual approach, the use of the oral narcotic antagonist, Naltrexone, was given to three such patients. Naltrexone binds multiple opiate receptor sites in the hypothalamus, including the kappa receptors which have been implicated in appetite regulation, the use of this narcotic antagonist in hypothalamic hyperphagia appears to be a rational approach to this intractable problem. In this open trial, lasting from 4 1/2 to 9 months, the minimal effective dose appeared to be in the range of 100 mg per day. No side-effects (for example elevations in liver enzymes) were noted. All of the patients had an improved sense of well-being and their behaviours were less difficult to manage when on the Naltrexone. The significance of this preliminary trial is that narcotic antagonists may have a role in the treatment of brain-injured patients with bulimia. Also, Naltrexone may be useful in treating other maladaptive behavioural consequences of head trauma such as stealing, manipulation, demandingness, and depression. Likewise, the effects on the deranged endocrine system, such as the hypogonadism, are significant and deserve further exploration.

  1. Naltrexone for impulse control disorders in Parkinson disease

    PubMed Central

    Papay, Kimberly; Xie, Sharon X.; Stern, Matthew; Hurtig, Howard; Siderowf, Andrew; Duda, John E.; Minger, James

    2014-01-01

    Objective: Impulse control disorders (ICDs) in Parkinson disease (PD) are common and can be difficult to manage. The objective of this study was to determine the efficacy and tolerability of naltrexone, an opioid antagonist, for the treatment of ICDs in PD. Methods: Patients with PD (n = 50) and an ICD were enrolled in an 8-week, randomized (1:1), double-blind, placebo-controlled study of naltrexone 50–100 mg/d (flexible dosing). The primary outcome measure was response based on the Clinical Global Impression–Change score, and the secondary outcome measure was change in symptom severity using the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease–Rating Scale (QUIP-RS) ICD score. Results: Forty-five patients (90%) completed the study. The Clinical Global Impression–Change response rate difference favoring naltrexone in completers was 19.8% (95% confidence interval [CI] −8.7% to 44.2%). While this difference was not significant (odds ratio = 1.6, 95% CI 0.5–5.2, Wald χ2 [df] = 0.5 [1], p = 0.5), naltrexone treatment led to a significantly greater decrease in QUIP-RS ICD score over time compared with placebo (regression coefficient for interaction term in linear mixed-effects model = −7.37, F[df] = 4.3 [1, 49], p = 0.04). The estimated changes in QUIP-RS ICD scores from baseline to week 8 were 14.9 points (95% CI 9.9–19.9) for naltrexone and 7.5 points (95% CI 2.5–12.6) for placebo. Conclusions: Naltrexone treatment was not efficacious for the treatment of ICDs in PD using a global assessment of response, but findings using a PD-specific ICD rating scale support further evaluation of opioid antagonists for the treatment of ICD symptoms in PD. Classification of evidence: This study provides Class I evidence that in patients with PD and an ICD, naltrexone does not significantly increase the probability of achieving response. However, the study lacked the precision to exclude an important difference in response rates. PMID

  2. Naltrexone/bupropion: Contrave(R); naltrexone SR/bupropion SR.

    PubMed

    2010-01-01

    In March 2010, Orexigen(R) Therapeutics submitted a new drug application (NDA) for approval of naltrexone sustained release (SR)/bupropion SR (Contrave(R)) for the treatment of obesity in the US. The tablet contains naltrexone SR 32 mg and bupropion SR 360 mg. The drug has been tested in four randomized, double-blind, placebo-controlled, phase III trials and the co-primary endpoints were met in each case. This review discusses the key development milestones and clinical trial program to date.

  3. Statistical distributions of ultra-low dose CT sinograms and their fundamental limits

    NASA Astrophysics Data System (ADS)

    Lee, Tzu-Cheng; Zhang, Ruoqiao; Alessio, Adam M.; Fu, Lin; De Man, Bruno; Kinahan, Paul E.

    2017-03-01

    Low dose CT imaging is typically constrained to be diagnostic. However, there are applications for even lowerdose CT imaging, including image registration across multi-frame CT images and attenuation correction for PET/CT imaging. We define this as the ultra-low-dose (ULD) CT regime where the exposure level is a factor of 10 lower than current low-dose CT technique levels. In the ULD regime it is possible to use statistically-principled image reconstruction methods that make full use of the raw data information. Since most statistical based iterative reconstruction methods are based on the assumption of that post-log noise distribution is close to Poisson or Gaussian, our goal is to understand the statistical distribution of ULD CT data with different non-positivity correction methods, and to understand when iterative reconstruction methods may be effective in producing images that are useful for image registration or attenuation correction in PET/CT imaging. We first used phantom measurement and calibrated simulation to reveal how the noise distribution deviate from normal assumption under the ULD CT flux environment. In summary, our results indicate that there are three general regimes: (1) Diagnostic CT, where post-log data are well modeled by normal distribution. (2) Lowdose CT, where normal distribution remains a reasonable approximation and statistically-principled (post-log) methods that assume a normal distribution have an advantage. (3) An ULD regime that is photon-starved and the quadratic approximation is no longer effective. For instance, a total integral density of 4.8 (ideal pi for 24 cm of water) for 120kVp, 0.5mAs of radiation source is the maximum pi value where a definitive maximum likelihood value could be found. This leads to fundamental limits in the estimation of ULD CT data when using a standard data processing stream

  4. A sudden and unprecedented increase in low dose naltrexone (LDN) prescribing in Norway. Patient and prescriber characteristics, and dispense patterns. A drug utilization cohort study.

    PubMed

    Raknes, Guttorm; Småbrekke, Lars

    2017-02-01

    Following a TV documentary in 2013, there was a tremendous increase in low dose naltrexone (LDN) use in a wide range of unapproved indications in Norway. We aim to describe the extent of this sudden and unprecedented increase in LDN prescribing, to characterize patients and LDN prescribers, and to estimate LDN dose sizes. LDN prescriptions recorded in the Norwegian Prescription Database (NorPD) in 2013 and 2014, and sales data not recorded in NorPD from the only Norwegian LDN manufacturer were included in the study. According to NorPD, 15 297 patients (0.3% of population) collected at least one LDN prescription. The actual number of users was higher as at least 23% of total sales were not recorded in NorPD. After an initial wave, there was a steady stream of new and persistent users throughout the study period. Median patient age was 52 years, and 74% of patients were female. Median daily dose was 3.7 mg. Twenty percent of all doctors and 71% of general medicine practitioners registered in Norway in 2014 prescribed LDN at least once. The TV documentary on LDN in Norway was followed by a large increase in LDN prescribing, and the proportion of LDN users went from an insignificant number to 0.3% of the population. There was a high willingness to use and prescribe off label despite limited evidence. Observed median LDN dose, and age and gender distribution were as expected in typical LDN using patients. © 2016 The Authors. Pharmacoepidemiology and Drug Safety Published by John Wiley & Sons Ltd. © 2016 The Authors. Pharmacoepidemiology and Drug Safety Published by John Wiley & Sons Ltd.

  5. Prevention and diminished expression of experimental autoimmune encephalomyelitis by low dose naltrexone (LDN) or opioid growth factor (OGF) for an extended period: Therapeutic implications for multiple sclerosis.

    PubMed

    Rahn, Kristen A; McLaughlin, Patricia J; Zagon, Ian S

    2011-03-24

    Endogenous opioids inhibit the onset and progression of experimental autoimmune encephalomyelitis (EAE) with 30days of treatment. This study examined the long term effects of the opioid growth factor (OGF, [Met(5)]-enkephalin) and a low dose of the opioid antagonist naltrexone (LDN) on expression of myelin oligodendrocyte glycoprotein (MOG)-induced EAE. C57BL/6 mice began receiving daily injections of 10mg/kg OGF (MOG+OGF), 0.1mg/kg naltrexone (MOG+LDN), or saline (MOG+Vehicle) at the time of EAE induction and continuing for 60days. In contrast to 100% of the MOG+Vehicle group with behavioral symptoms of EAE, 63% and 68% of the MOG+OGF and MOG+LDN mice expressed disease. Both severity and disease indices of EAE in OGF- and LDN-treated mice were notably decreased from MOG+Vehicle cohorts. By day 60, 6- and 3-fold more animals in the MOG+OGF and MOG+LDN groups, respectively, had a remission compared to MOG+Vehicle mice. Neuropathological studies revealed i) astrocyte activation and neuronal damage as early as day 10 (prior to behavioral symptoms) in all MOG-injected groups, ii) a significant reduction of activated astrocytes in MOG+OGF and MOG+LDN groups compared to MOG+Vehicle mice at day 30, and iii) no demyelination on day 60 in mice treated with OGF or LDN and not displaying disease symptoms. These results indicate that treatment with OGF or LDN had no deleterious long-term repercussions and did not exacerbate EAE, but i) halted progression of disease, ii) reversed neurological deficits, and iii) prevented the onset of neurological dysfunction across a considerable span of time. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. The effect of low-dose naltrexone on quality of life of patients with multiple sclerosis: a randomized placebo-controlled trial.

    PubMed

    Sharafaddinzadeh, Naser; Moghtaderi, Ali; Kashipazha, Davood; Majdinasab, Nastaran; Shalbafan, Bita

    2010-08-01

    Low-dose naltrexone (LDN) may promote psychological well-being as well as generalized health especially in autoimmune disorders. The objective of this study is to assess the effect of LDN on the Quality of Life (QoL) of patients with relapsing-remitting and secondary progressive multiple sclerosis (MS) using the scales and composite scores of the MSQoL-54 questionnaire. A 17-week randomized, double-blind, placebo-controlled, parallel-group, crossover-design clinical trial was conducted in two universities. A total of 96 adult patients aged between 15 and 65 years with relapsing-remitting (RR) or secondary progressive (SP) clinically definite MS with disease duration longer than 6 months enrolled into the study. The primary outcome of the study was comparison of the scores of physical and mental health by conducting independent t-test of the results obtained in the middle and at the end of study between the two groups. Variables including presence of pain, energy, emotional well-being, social, cognitive, and sexual functions, role limitation due to physical and emotional problems, health distress, and overall QoL did not show any meaningful statistically difference between the two groups. Factor analysis revealed that health perception scores were statistically different between the groups before starting, in the middle, and at the end of the study. The study clearly illustrates that LDN is a relatively safe therapeutic option in RRMS and SPMS but its efficacy is under question and probably a long duration trial is needed in the future.

  7. Evaluation of an iterative model-based CT reconstruction algorithm by intra-patient comparison of standard and ultra-low-dose examinations.

    PubMed

    Noël, Peter B; Engels, Stephan; Köhler, Thomas; Muenzel, Daniela; Franz, Daniela; Rasper, Michael; Rummeny, Ernst J; Dobritz, Martin; Fingerle, Alexander A

    2018-01-01

    Background The explosive growth of computer tomography (CT) has led to a growing public health concern about patient and population radiation dose. A recently introduced technique for dose reduction, which can be combined with tube-current modulation, over-beam reduction, and organ-specific dose reduction, is iterative reconstruction (IR). Purpose To evaluate the quality, at different radiation dose levels, of three reconstruction algorithms for diagnostics of patients with proven liver metastases under tumor follow-up. Material and Methods A total of 40 thorax-abdomen-pelvis CT examinations acquired from 20 patients in a tumor follow-up were included. All patients were imaged using the standard-dose and a specific low-dose CT protocol. Reconstructed slices were generated by using three different reconstruction algorithms: a classical filtered back projection (FBP); a first-generation iterative noise-reduction algorithm (iDose4); and a next generation model-based IR algorithm (IMR). Results The overall detection of liver lesions tended to be higher with the IMR algorithm than with FBP or iDose4. The IMR dataset at standard dose yielded the highest overall detectability, while the low-dose FBP dataset showed the lowest detectability. For the low-dose protocols, a significantly improved detectability of the liver lesion can be reported compared to FBP or iDose 4 ( P = 0.01). The radiation dose decreased by an approximate factor of 5 between the standard-dose and the low-dose protocol. Conclusion The latest generation of IR algorithms significantly improved the diagnostic image quality and provided virtually noise-free images for ultra-low-dose CT imaging.

  8. Putting the brakes on the "drive to eat": Pilot effects of naltrexone and reward based eating on food cravings among obese women

    PubMed Central

    Mason, Ashley E.; Laraia, Barbara; Daubenmier, Jennifer; Hecht, Frederick M.; Lustig, Robert H.; Puterman, Eli; Adler, Nancy; Dallman, Mary; Kiernan, Michaela; Gearhardt, Ashley N.; Epel, Elissa S.

    2015-01-01

    Purpose Obese individuals vary in their experience of food cravings and tendency to engage in reward-driven eating, both of which can be modulated by the neural reward system rather than physiological hunger. We examined two predictions in a sample of obese women: (1) whether opioidergic blockade reduced food-craving intensity, and (2) whether opioidergic blockade reduced an association between food-craving intensity and reward-driven eating, which is a trait-like index of three factors (lack of control over eating, lack of satiation, preoccupation with food). Methods Forty-four obese, pre-menopausal women completed the Reward-based Eating Drive (RED) scale at study start and daily food-craving intensity on 5 days on which they ingested either a pill-placebo (2 days), a 25mg naltrexone dose (1 day), or a standard 50mg naltrexone dose (2 days). Results Craving intensity was similar under naltrexone and placebo doses. The association between food-craving intensity and reward-driven eating significantly differed between placebo and 50mg naltrexone doses. Reward-driven eating and craving intensity were significantly positively associated under both placebo doses. As predicted, opioidergic blockade (for both doses 25mg and 50mg naltrexone) reduced this positive association between reward-driven eating and craving intensity to non-significance. Conclusions Opioidergic blockade did not reduce craving intensity; however, blockade reduced an association between trait-like reward-driven eating and daily food-craving intensity, and may help identify an important endophenotype within obesity. PMID:26164674

  9. Effects of naltrexone on alcohol drinking patterns and extinction of alcohol seeking in baboons

    PubMed Central

    Kaminski, Barbara J.; Duke, Angela N.; Weerts, Elise M.

    2012-01-01

    Rationale Understanding naltrexone’s effect on motivation to drink and pattern of drinking is important for better treatment outcomes and for comparison with novel medications. Objectives Naltrexone’s effects on number and pattern of seeking, self-administration, and extinction responses were evaluated in two groups of baboons trained under a 3 component chained schedule of reinforcement (CSR). Methods Alcohol (4% w/v; n=4; Alcohol Group) or a preferred non-alcoholic beverage (n=4; Control Group) was available for self-administration only in Component 3 of the CSR. Responses in Component 2 provided indices of motivation to drink (seeking). Naltrexone (0.32 – 3.2 mg/kg) and saline were administered before drinking and Component 2 extinction sessions. Results Acute doses of naltrexone significantly decreased total self-administration responses (p<0.01), intake volume (p<0.001) and g/kg of alcohol (p<0.01) in the Alcohol Group only. Pattern of drinking did not change, but number of drinks during the initial drinking bout was decreased significantly by naltrexone for both groups (P<0.05). During within-session extinction tests, acute naltrexone significantly decreased time to reach extinction (p<0.01) and number of seeking responses (p<0.05), particularly early in the extinction period in the Alcohol Group only. When administered chronically, naltrexone did not decrease progressive-ratio breaking points to gain access to alcohol, but dose-dependently reduced alcohol self-administration (p<0.05) by decreasing the magnitude of the initial drinking bout. Conclusions The results support clinical observations that naltrexone may be most effective at reducing self-administration in the context of ongoing alcohol availability and may reduce motivation to drink in the presence of alcohol-related cues. PMID:22451093

  10. The Effects of ELDRS at Ultra-Low Dose Rates

    NASA Technical Reports Server (NTRS)

    Chen, Dakai; Forney, James; Carts, Martin; Phan, Anthony; Pease, Ronald; Kruckmeyer, Kirby; Cox, Stephen; LaBel, Kenneth; Burns, Samuel; Albarian, Rafi; hide

    2011-01-01

    We present results on the effects on ELDRS at dose rates of 10, 5, 1, and 0.5 mrad(Si)/s for a variety of radiation hardened and commercial devices. We observed low dose rate enhancement below 10 mrad(Si)/s in several different parts. The magnitudes of the dose rate effects vary. The TL750L, a commercial voltage regulator, showed dose rate dependence in the functional failures, with initial failures occurring after 10 krad(Si) for the parts irradiated at 0.5 mrad(Si)/s. The RH1021 showed an increase in low dose rate enhancement by 2x at 5 mrad(Si)/s relative to 8 mrad(Si)/s and high dose rate, and parametric failure after 100 krad(Si). Additionally the ELDRS-free devices, such as the LM158 and LM117, showed evidence of dose rate sensitivity in parametric degradations. Several other parts also displayed dose rate enhancement, with relatively lower degradations up to approx.15 to 20 krad(Si). The magnitudes of the dose rate enhancement will likely increase in significance at higher total dose levels.

  11. Acute behavioural effects of bupropion and naltrexone, alone and in combination, in non-deprived male rats presented with palatable mash.

    PubMed

    Wright, F L; Rodgers, R J

    2013-07-01

    In appetite research, drugs frequently progress to clinical trials on the basis of outcome (reduced food intake/body weight gain) with insufficient attention to process (behavioural analysis). Although bupropion and naltrexone (alone and in combination) reduce food consumption in rodents and humans, their effects on behaviour during feeding tests have not been thoroughly investigated. This study aimed to assess the behavioural specificity of anorectic responses to bupropion, naltrexone and their combination. Video analysis was employed to characterise the behavioural effects of acute systemic treatment with bupropion (10.0-40.0 mg/kg), naltrexone (0.1-3.0 mg/kg) and combined bupropion (20 mg/kg) plus naltrexone (0.1-1.0 mg/kg) in non-deprived male rats exposed for 1 h to palatable mash. Particular attention was paid to the behavioural satiety sequence (BSS). In experiment 1, the anorectic response to 40 mg/kg bupropion was associated with significant psychomotor stimulation and a complete disruption of the BSS. In experiment 2, the anorectic response to 3 mg/kg naltrexone was associated with an accelerated but otherwise normal BSS. In experiment 3, the co-administration of 20 mg/kg bupropion and naltrexone (0.1 and 1.0 mg/kg) not only produced an additive anorectic profile (including a reduced rate of eating), but the addition of the opioid receptor antagonist also concurrently attenuated the psychomotor stimulant response to the atypical antidepressant. Low-dose co-treatment with naltrexone and bupropion produces a stronger suppression of appetite than that seen with either agent alone and has the additional advantage of reducing some of the unwanted effects of bupropion.

  12. Naltrexone

    MedlinePlus

    ... other information should I know? Brand names IMPORTANT WARNING: Naltrexone may cause liver damage when taken in ... these symptoms or those listed in the IMPORTANT WARNING section, call your doctor immediately: confusion hallucinations (seeing ...

  13. Evaluation of an ultra-low-dose oral contraceptive for dysmenorrhea: a placebo-controlled, double-blind, randomized trial.

    PubMed

    Harada, Tasuku; Momoeda, Mikio

    2016-12-01

    To evaluate the efficacy and safety of an ultra-low-dose oral contraceptive (NPC-01; 0.02 mg ethinyl estradiol and 1 mg norethisterone) in subjects with dysmenorrhea. Placebo-controlled, double-blind, randomized trial. Clinical trial sites. Two hundred fifteen subjects with dysmenorrhea. Subjects were randomly assigned to receive NPC-01, placebo, or IKH-01 (0.035 mg ethinyl estradiol and 1 mg norethisterone) for four cycles. Total dysmenorrhea score (verbal rating scale) assessing pain on the basis of limited ability to work and need for analgesics. The reductions of total dysmenorrhea score and visual analog scale score after the treatment were significantly higher in the NPC-01 group than in the placebo group. Furthermore, the efficacy of NPC-01 was comparable to that of IKH-01. The overall incidence of side effects was significantly higher in the NPC-01 group than in the placebo group. All side effects that occurred in the NPC-01 group were previously reported in patients receiving IKH-01. No serious side effects occurred. The ultra-low-dose contraceptive NPC-01 relieved dysmenorrhea as effectively as IKH-01. Thus, NPC-01 could represent a new option for long-term treatment of dysmenorrhea. NCT01129102. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  14. Naltrexone

    MedlinePlus

    ... Dependence When used as a treatment for alcohol dependency, naltrexone blocks the euphoric effects and feelings of ... dispense and prescribe medications for opioid and alcohol dependency. SAMHSA’s Division of Pharmacologic Therapies (DPT) provides opioid ...

  15. A Theoretical Approach to Selection of a Biologically Active Substance in Ultra-Low Doses for Effective Action on a Biological System.

    PubMed

    Boldyreva, Liudmila Borisovna

    2018-05-01

     An approach is offered to selecting a biologically active substance (BAS) in ultra-low dose for effective action on a biological system (BS). The technique is based on the assumption that BAS in ultra-low doses exerts action on BS by means of spin supercurrent emerging between the spin structure created by BAS, on the one hand, and the spin structure created by BS, on the other hand. According to modern quantum-mechanical concepts, these spin structures may be virtual particles pairs having precessing spin (that is, be essentially spin vortices in the physical vacuum) and created by the quantum entities that BAS and BS consist of. The action is effective provided there is equality of precession frequencies of spins in these spin structures.  In this work, some methods are considered for determining the precession frequencies of spins in virtual particles pairs: (1) determination of energy levels of quantum entities that BS and BAS consist of; (2) the use of spin-flip effect of the virtual particles pair spin, the effect being initiated by action of magnetic vector potential (the spin-flip effect takes place when the varied frequency of the magnetic vector potential equals the precession frequency of the spin); (3) determining the frequencies of photons effectively acting on BS.  It is shown that the effect of BAS in ultra-low doses on BS can be replaced by the effect of a beam of low-intensity photons, if the frequency of photons equals the precession frequency of spin in spin structures created by BS. Consequently, the color of bodies placed near a biological system is able to exert an effective action on the biological system: that is "color therapy" is possible. It is also supposed that the spin-flip effect may be used not only for determining the precession frequency of spin in spin structures created by BS but also for therapeutic action on biological systems. The Faculty of Homeopathy.

  16. Effects of Naltrexone on Smoking Cessation Outcomes and Weight Gain in Nicotine-Dependent Men and Women

    PubMed Central

    King, Andrea C.; Cao, Dingcai; O'Malley, Stephanie S.; Kranzler, Henry R.; Cai, Xiaochen; deWit, Harriet; Matthews, Alicia K.; Stachoviak, Ryan J.

    2015-01-01

    This study examined whether the opioid receptor antagonist naltrexone is efficacious in smoking cessation and whether sex moderates the response. We assessed smoking quit rates and weight gain in a double-blind randomized trial comparing oral naltrexone (n = 162) with placebo (n = 154) in nicotine-dependent participants who wanted to quit smoking. The medication was gradually titrated up to 50 mg during the week before the quit date and then maintained at this dose for 12 weeks. For the first 4 weeks after the quit date, all participants received a nicotine patch to mitigate tobacco withdrawal and attended weekly individual cognitive-behavioral smoking cessation counseling sessions. After this time, participants continued with naltrexone or placebo through 12 weeks. Follow-up assessments were conducted at 26 and 52 weeks. During treatment, naltrexone (vs placebo) increased quit rates, attenuated smoking urge, and reduced weight gain. At follow-up, after medication discontinuation, the effect of naltrexone on improving quit rates was no longer evident. Men and women experienced different benefits from naltrexone; men showed greater reductions in smoking, whereas women showed greater reductions in weight gain. In sum, naltrexone showed acute efficacy in treating nicotine dependence, but after the medication was discontinued, the effect on quit rate was not maintained. Further study of naltrexone in smoking cessation treatment and reduction of cessation-related weight gain, as well as preclinical investigation of mechanisms underlying sex differences, is warranted. PMID:22926596

  17. Separate and Combined Effects of Naltrexone and Extended-Release Alprazolam on the Reinforcing, Subject-Rated, and Cardiovascular Effects of Methamphetamine

    PubMed Central

    Marks, Katherine R.; Lile, Joshua A.; Stoops, William W.; Glaser, Paul E.A.; Hays, Lon R.; Rush, Craig R.

    2016-01-01

    Opioid antagonists (e.g., naltrexone) and positive modulators of γ-aminobutyric acid type A (GABAA) receptors (e.g., alprazolam) each modestly attenuate the abuse-related effects of stimulants. A previous study demonstrated that acute pretreatment with the combination of naltrexone and alprazolam attenuated a greater number of the subject-rated effects of d-amphetamine than the constituent drugs alone. This study tested the hypothesis that maintenance on the combination of naltrexone and alprazolam XR would attenuate the reinforcing and “positive” subject-rated effects of methamphetamine to a greater extent than the constituent drugs alone. Eight non-treatment-seeking, stimulant-using individuals completed a placebo-controlled, crossover, double-blind inpatient protocol. Participants were maintained on naltrexone (0 and 50 mg), alprazolam XR (0 and 1 mg), and the combination of naltrexone and alprazolam XR (50 mg and 1 mg, respectively) for 6–7 days. Under each maintenance condition, participants sampled intranasal doses of methamphetamine (0, 10, and 30 mg), and were then offered the opportunity to work for the sampled dose on a modified progressive-ratio procedure. Subject-rated drug effect questionnaires, psychomotor, and physiology assessments were collected. Intranasal methamphetamine functioned as a reinforcer and produced prototypical stimulant-like “positive” subject-rated and physiological effects. Maintenance on naltrexone significantly decreased the reinforcing, but not subject-rated drug effects of 10 mg methamphetamine. Alprazolam XR and the combination of naltrexone and alprazolam XR did not impact methamphetamine self-administration or subject-rated drug effects. The results support the continued evaluation of naltrexone for methamphetamine dependence, as well as the identification of other drugs that enhance its ability to reduce drug-taking behavior. PMID:27043121

  18. Separate and Combined Effects of Naltrexone and Extended-Release Alprazolam on the Reinforcing, Subject-Rated, and Cardiovascular Effects of Methamphetamine.

    PubMed

    Marks, Katherine R; Lile, Joshua A; Stoops, William W; Glaser, Paul E A; Hays, Lon R; Rush, Craig R

    2016-06-01

    Opioid antagonists (eg, naltrexone) and positive modulators of γ-aminobutyric acid type A receptors (eg, alprazolam) each modestly attenuate the abuse-related effects of stimulants. A previous study demonstrated that acute pretreatment with the combination of naltrexone and alprazolam attenuated a greater number of the subject-rated effects of D-amphetamine than the constituent drugs alone. This study tested the hypothesis that maintenance on the combination of naltrexone and alprazolam XR would attenuate the reinforcing and "positive" subject-rated effects of methamphetamine to a greater extent than the constituent drugs alone.Eight non-treatment-seeking, stimulant-using individuals completed a placebo-controlled, crossover, double-blind inpatient protocol. Participants were maintained on naltrexone (0 and 50 mg), alprazolam XR (0 and 1 mg), and the combination of naltrexone and alprazolam XR (50 mg and 1 mg, respectively) for 6 to 7 days. Under each maintenance condition, participants sampled intranasal doses of methamphetamine (0, 10, and 30 mg), and were then offered the opportunity to work for the sampled dose on a modified progressive-ratio procedure. Subject-rated drug effect questionnaires, psychomotor, and physiology assessments were collected.Intranasal methamphetamine functioned as a reinforcer and produced prototypical stimulant-like "positive" subject-rated and physiological effects. Maintenance on naltrexone significantly decreased the reinforcing, but not subject-rated drug effects of 10-mg methamphetamine. Alprazolam XR and the combination of naltrexone and alprazolam XR did not impact methamphetamine self-administration or subject-rated drug effects. The results support the continued evaluation of naltrexone for methamphetamine dependence, as well as the identification of other drugs that enhance its ability to reduce drug-taking behavior.

  19. Naltrexone + bupropion (Mysimba). Too risky for only modest weight loss.

    PubMed

    2015-10-01

    Weight loss and its long-term maintenance are mainly based on dietary measures and regular physical activity. There are currently no weight-loss medications with a favourable harm-benefit balance. Bupropion is chemically related to certain amphetamines, while naltrexone is an opioid receptor antagonist. A fixed-dose combination of these two drugs has received marketing authorisation in the European Union for obese patients and for over-weight patients with other cardiovascular risk factors. In five placebo-controlled, randomised, double-blind trials, the patients, weighing on average between 100 kg and 105 kg (average body mass index 36 kg/m2), the naltrexone + bupropion combination was associated with an average weight loss of a few additional kilograms compared with placebo, after 6 months or one year of treatment. There are no post-trial follow-up data to show whether or not the patients regained their lost weight after treatment discontinuation. One trial including more than 8900 patients examined the effect of the naltrexone + bupropion combination on the freauency of maior cardiovascular events, but poor handling of an interim analysis undermined the validity of the final results. The known adverse effects of bupropion consist of potentially severe neuropsychiatric disorders such as aggressiveness, depression and suicidal ideation, and also allergic reactions, including Stevens-Johnson syndrome. Misuse and excessive consumption have been reported. In trials in obese or overweight patients, the naltrexone + bupropion combination caused sometimes severe neuropsychiatric disorders, including seizures, cognitive impairment, dizziness, anxiety, sleep disorders and psychotic symptoms. In clinical trials, the combination led to an increase in blood pressure compared with placebo, and also an excess of cardiac arrhythmias. About half of patients who took naltrexone + bupropion experienced gastrointestinal disorders such as nausea, vomiting and constipation. The

  20. Risk-Taking Propensity as a Predictor of Induction onto Naltrexone Treatment for Opioid Dependence

    PubMed Central

    Aklin, Will M.; Severtson, S. Geoffrey; Umbricht, Annie; Fingerhood, Michael; Bigelow, George E.; Lejuez, C. W.; Silverman, Kenneth

    2014-01-01

    Objective Heroin addiction is a chronic relapsing disorder that has devastating social, medical, and economic consequences. Naltrexone is an antagonist that blocks opioid effects and could be an effective medication for the treatment of opioid dependence. However, its clinical utility has been limited partly because of poor adherence and acceptability. Given the importance of compliance to naltrexone treatment for opioid dependence, the goal of the current study was to examine predictors involved in successful induction onto naltrexone treatment. Method Parametric and nonparametric statistical tests were performed on data from a sample of 64 individuals entering treatment who met DSM-IV criteria for opioid dependence. The relationship between naltrexone induction (i.e., inducted- vs. not-inducted onto naltrexone) and risk-taking propensity, as indexed by riskiness on the Balloon Analogue Risk Task (BART) was examined. Participants were recruited from local detoxification programs, inpatient drug treatment, and other Baltimore programs that provided services to opioid dependent adults (e.g., Baltimore Needle Exchange Program) during the period from August 2007 to September 2008. Results Positive association between risk-taking propensity and odds of naltrexone induction. Specifically, each five point increase in the total BART score was associated with a 25% decrease in odds of naltrexone induction (OR=0.76, 95% CI: 0.58–0.99, p = .041). This association remained statistically significant even after adjusting for potential confounds, including injection drug use and cocaine positive urine results (p = .05). After adjusting for the covariates, each five point increase in BART score was associated with 28% decrease in the odds of achieving the maintenance dose (AOR=0.73, 95% CI: 0.54–0.99, p = .046). Conclusions Risk taking propensity was predictive of induction onto naltrexone treatment, above and beyond injection drug use and cocaine-positive urine samples. PMID

  1. Ultra-low dose of intravitreal bevacizumab in retinopathy of prematurity.

    PubMed

    Şahin, A; Gürsel-Özkurt, Z; Şahin, M; Türkcü, F M; Yıldırım, A; Yüksel, H

    2018-05-01

    We aimed to investigate the effectivity of the 0.0625 mg dose of bevacizumab in patients with retinopathy of prematurity (ROP) and compare the results with 0.625 mg dose of intravitreal bevacizumab (IVB) injection. The medical records of the patients with type 1 ROP who received IVB monotherapy were retrospectively reviewed. Demographic and clinical characteristics of the patients were recorded. The patients were classified into two groups with respect to received dose of bevacizumab as follows: group F (n = 46) (full dose of bevacizumab-0.625 mg/0.025 ml) and group L (n = 45) (low dose (one tenth) of bevacizumab-0.0625 mg/0.025 ml). Both treatment dose regimens have similar outcomes. Moreover, the mean retinal vascularization time seemed to be significantly higher in group F compared to group L, 168 ± 65 and 97 ± 29 days, respectively (p < 0.001). Disappearance of plus sign is observed earlier in group F (2.45 ± 1.7 vs 3.66 ± 2.46 days, respectively, p = 0.03). The low dose (0.0625 mg) of IVB treatment was effective as full (0.625 mg) dose in ROP treatment. Moreover, our results showed that low-dose treatment might provide faster retinal vascularization than the regular used dose. On the other hand, disappearance of the plus sign takes longer time in patients treated with low dose compared to eyes treated with full dose of IVB that should be taken into account.

  2. Low-dose naltrexone targets the opioid growth factor-opioid growth factor receptor pathway to inhibit cell proliferation: mechanistic evidence from a tissue culture model.

    PubMed

    Donahue, Renee N; McLaughlin, Patricia J; Zagon, Ian S

    2011-09-01

    Naltrexone (NTX) is an opioid antagonist that inhibits or accelerates cell proliferation in vivo when utilized in a low (LDN) or high (HDN) dose, respectively. The mechanism of opioid antagonist action on growth is not well understood. We established a tissue culture model of LDN and HDN using short-term and continuous opioid receptor blockade, respectively, in human ovarian cancer cells, and found that the duration of opioid receptor blockade determines cell proliferative response. The alteration of growth by NTX also was detected in cells representative of pancreatic, colorectal and squamous cell carcinomas. The opioid growth factor (OGF; [Met(5)]-enkephalin) and its receptor (OGFr) were responsible for mediating the action of NTX on cell proliferation. NTX upregulated OGF and OGFr at the translational but not at the transcriptional level. The mechanism of inhibition by short-term NTX required p16 and/or p21 cyclin-dependent inhibitory kinases, but was not dependent on cell survival (necrosis, apoptosis). Sequential administration of short-term NTX and OGF had a greater inhibitory effect on cell proliferation than either agent alone. Given the parallels between short-term NTX in vitro and LDN in vivo, we now demonstrate at the molecular level that the OGF-OGFr axis is a common pathway that is essential for the regulation of cell proliferation by NTX.

  3. Low-dose naltrexone suppresses ovarian cancer and exhibits enhanced inhibition in combination with cisplatin.

    PubMed

    Donahue, Renee N; McLaughlin, Patricia J; Zagon, Ian S

    2011-07-01

    Ovarian cancer is the leading cause of death from gynecological malignancies. Although initial therapeutic modalities are successful, 65% of these women relapse with only palliative treatments available thereafter. Endogenous opioids repress the proliferation of human ovarian cancer cells in vitro, and do so in a receptor-mediated manner. The present study examined whether modulation of opioid systems by the opioid antagonist naltrexone (NTX), alone or in combination with standard of care therapies (taxol/paclitaxel, cisplatin), alters human ovarian cancer cell proliferation in tissue culture and tumor progression in mice. Administration of NTX for six hours every two days, but not continuously, reduced DNA synthesis and cell replication from vehicle-treated controls in tissue culture. Moreover, brief exposure to NTX in combination with taxol or cisplatin had an enhanced anticancer action. Mice with established ovarian tumors and treated with a low dosage of NTX (LDN), which invokes a short period of opioid receptor blockade, repressed tumor progression in a non-toxic fashion by reducing DNA synthesis and angiogenesis but not altering cell survival. The combination of LDN with cisplatin, but not taxol, resulted in an additive inhibitory effect on tumorigenesis with enhanced depression of DNA synthesis and angiogenesis. LDN combined with cisplatin alleviated the toxicity (e.g. weight loss) associated with cisplatin. LDN treatment upregulated the expression of the opioid growth factor (OGF, chemical term ([Met(5)]-enkephalin) and its receptor, OGFr. Previous tissue culture studies have reported that OGF is the only opioid peptide with antiproliferative activity on ovarian cancer cells, with OGF action mediated by OGFr. Thus, the common denominator of intermittent opioid receptor blockade by short-term NTX or LDN on ovarian cancer proliferation and tumorigenesis recorded herein appears to be related to the OGF-OGFr axis. These preclinical data may offer a non

  4. Dextromethorphan plus ultra low-dose quinidine reduces pseudobulbar affect.

    PubMed

    Pioro, Erik P; Brooks, Benjamin Rix; Cummings, Jeffrey; Schiffer, Randolph; Thisted, Ronald A; Wynn, Daniel; Hepner, Adrian; Kaye, Randall

    2010-11-01

    To evaluate dextromethorphan combined with ultra low-dose quinidine (DMq) for treating pseudobulbar affect (PBA) in patients with amyotrophic lateral sclerosis (ALS) or multiple sclerosis (MS). In a 12-week randomized, double-blind trial, ALS and MS patients with clinically significant PBA (a baseline score ≥13 on the Center for Neurologic Studies-Lability Scale [CNS-LS]) were maintained, twice daily, on placebo, DMq at 30/10mg (DMq-30), or DMq at 20/10mg (DMq-20). In 326 randomized patients (of whom 283, or 86.8%, completed the study), the PBA-episode daily rate was 46.9% (p < 0.0001) lower for DMq-30 than for placebo and 49.0% (p < 0.0001) lower for DMq-20 than for placebo by longitudinal negative binomial regression, the prespecified primary analysis. Mean CNS-LS scores decreased by 8.2 points for DMq-30 and 8.2 for DMq-20, vs 5.7 for placebo (p= 0.0002 and p= 0.0113, respectively). Other endpoints showing statistically significant DMq benefit included, for both dosage levels, the likelihood of PBA remission during the final 14 days and, for the higher dosage, improvement on measures of social functioning and mental health. Both dosages were safe and well tolerated. DMq markedly reduced PBA frequency and severity, decreasing the condition's detrimental impact on a patient's life, with satisfactory safety and high tolerability. The findings expand the clinical evidence that DMq may be an important treatment for patients suffering from the socially debilitating symptoms of PBA.

  5. SU-C-206-07: A Practical Sparse View Ultra-Low Dose CT Acquisition Scheme for PET Attenuation Correction in the Extended Scan Field-Of-View

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miao, J; Fan, J; Gopinatha Pillai, A

    Purpose: To further reduce CT dose, a practical sparse-view acquisition scheme is proposed to provide the same attenuation estimation as higher dose for PET imaging in the extended scan field-of-view. Methods: CT scans are often used for PET attenuation correction and can be acquired at very low CT radiation dose. Low dose techniques often employ low tube voltage/current accompanied with a smooth filter before backprojection to reduce CT image noise. These techniques can introduce bias in the conversion from HU to attenuation values, especially in the extended CT scan field-of-view (FOV). In this work, we propose an ultra-low dose CTmore » technique for PET attenuation correction based on sparse-view acquisition. That is, instead of an acquisition of full amount of views, only a fraction of views are acquired. We tested this technique on a 64-slice GE CT scanner using multiple phantoms. CT scan FOV truncation completion was performed based on the published water-cylinder extrapolation algorithm. A number of continuous views per rotation: 984 (full), 246, 123, 82 and 62 have been tested, corresponding to a CT dose reduction of none, 4x, 8x, 12x and 16x. We also simulated sparse-view acquisition by skipping views from the fully-acquired view data. Results: FBP reconstruction with Q. AC filter on reduced views in the full extended scan field-of-view possesses similar image quality to the reconstruction on acquired full view data. The results showed a further potential for dose reduction compared to the full acquisition, without sacrificing any significant attenuation support to the PET. Conclusion: With the proposed sparse-view method, one can potential achieve at least 2x more CT dose reduction compared to the current Ultra-Low Dose (ULD) PET/CT protocol. A pre-scan based dose modulation scheme can be combined with the above sparse-view approaches, which can even further reduce the CT scan dose during a PET/CT exam.« less

  6. A non-rewarding, non-aversive buprenorphine/naltrexone combination attenuates drug-primed reinstatement to cocaine and morphine in rats in a conditioned place preference paradigm.

    PubMed

    Cordery, Sarah F; Taverner, Alistair; Ridzwan, Irna E; Guy, Richard H; Delgado-Charro, M Begoña; Husbands, Stephen M; Bailey, Christopher P

    2014-07-01

    Concurrent use of cocaine and heroin is a major public health issue with no effective relapse prevention treatment currently available. To this purpose, a combination of buprenorphine and naltrexone, a mixed very-low efficacy mu-opioid receptor agonist/kappa-opioid receptor antagonist/nociceptin receptor agonist, was investigated. The tail-withdrawal and the conditioned place preference (CPP) assays in adult Sprague Dawley rats were used to show that naltrexone dose-dependently blocked the mu-opioid receptor agonism of buprenorphine. Furthermore, in the CPP assay, a combination of 0.3 mg/kg buprenorphine and 3.0 mg/kg naltrexone was aversive. A combination of 0.3 mg/kg buprenorphine and 1.0 mg/kg naltrexone was neither rewarding nor aversive, but still possessed mu-opioid receptor antagonist properties. In the CPP extinction and reinstatement method, a combination of 0.3 mg/kg buprenorphine and 1.0 mg/kg naltrexone completely blocked drug-primed reinstatement in cocaine-conditioned rats (conditioned with 3 mg/kg cocaine, drug prime was 3 mg/kg cocaine) and attenuated drug-primed reinstatement in morphine-conditioned rats (conditioned with 5 mg/kg morphine, drug prime was 1.25 mg/kg morphine). These data add to the growing evidence that a buprenorphine/naltrexone combination may be protective against relapse in a polydrug abuse situation. © 2012 The Authors, Addiction Biology © 2012 Society for the Study of Addiction.

  7. Ultra-Low-Dropout Linear Regulator

    NASA Technical Reports Server (NTRS)

    Thornton, Trevor; Lepkowski, William; Wilk, Seth

    2011-01-01

    A radiation-tolerant, ultra-low-dropout linear regulator can operate between -150 and 150 C. Prototype components were demonstrated to be performing well after a total ionizing dose of 1 Mrad (Si). Unlike existing components, the linear regulator developed during this activity is unconditionally stable over all operating regimes without the need for an external compensation capacitor. The absence of an external capacitor reduces overall system mass/volume, increases reliability, and lowers cost. Linear regulators generate a precisely controlled voltage for electronic circuits regardless of fluctuations in the load current that the circuit draws from the regulator.

  8. Baseline Characteristics of Patients Predicting Suitability for Rapid Naltrexone Induction

    PubMed Central

    Mogali, Shanthi; Khan, Nabil A.; Drill, Esther S.; Pavlicova, Martina; Sullivan, Maria A.; Nunes, Edward; Bisaga, Adam

    2015-01-01

    Background and Objectives Extended-release (XR) injection naltrexone has proved promising in the treatment of opioid dependence. Induction onto naltrexone is often accomplished with a procedure known as rapid naltrexone induction. The purpose of this study was to evaluate pre-treatment patient characteristics as predictors of successful completion of a rapid naltrexone induction procedure prior to XR naltrexone treatment. Methods A chart review of 150 consecutive research participants (N = 84 completers and N = 66 non-completers) undergoing a rapid naltrexone induction with the buprenorphone-clonidine procedure were compared on a number of baseline demographic, clinical and psychosocial factors. Logistic regression was used to identify client characteristics that may predict successful initiation of naltrexone after a rapid induction-detoxification. Results Patients who failed to successfully initiate naltrexone were younger (AOR: 1.040, CI: 1.006, 1.075), and using 10 or more bags of heroin (or equivalent) per day (AOR: 0.881, CI: 0.820, 0.946). Drug use other than opioids was also predictive of failure to initiate naltrexone in simple bivariate analyses, but was no longer significant when controlling for age and opioid use level. Conclusions Younger age, and indicators of greater substance dependence severity (more current opioid use, other substance use) predict difficulty completing a rapid naltrexone induction procedure. Such patients might require a longer period of stabilization and/or more gradual detoxification prior to initiating naltrexone. Scientific Significance Our study findings identify specific characteristics of patients who responded positively to rapid naltrexone induction. PMID:25907815

  9. Daily relations among affect, urge, targeted naltrexone, and alcohol use in young adults.

    PubMed

    Bold, Krysten W; Fucito, Lisa M; Corbin, William R; DeMartini, Kelly S; Leeman, Robert F; Kranzler, Henry R; O'Malley, Stephanie S

    2016-10-01

    Heavy drinking among young adults is a serious public health problem. Naltrexone, an opioid antagonist, has been shown to reduce drinking in young adults compared to placebo and can be taken on a targeted (i.e., as needed) basis. Understanding risk factors for drinking and naltrexone effects within-person in young adults may help to optimize the use of targeted naltrexone. The current study was a secondary analysis of daily diary data from 127 (n = 40 female) young adults (age 18-25) enrolled in a double-blind clinical trial of daily (25 mg) plus targeted (25 mg) naltrexone versus placebo. Hierarchical linear models were used to examine the effects of daily affect, urge, and taking targeted medication on same-day risk of drinking to intoxication (defined as estimated blood-alcohol-concentration, BAC ≥ .08 g%). Results indicated urge significantly mediated within-person positive affect-drinking relations on a daily level. Specifically, positive affect was associated with greater urge to drink, which in turn was associated with greater odds of BAC ≥ .08 g%. Furthermore, days of greater positive affect and urge were associated with taking a targeted dose of medication, which reduced the likelihood of intoxication by nearly 23% in the naltrexone group compared to placebo. Gender and family history of alcohol dependence were examined as moderators of these daily level effects. These results provide further evidence of naltrexone's ability to reduce alcohol consumption in young adults and identify potential within-person risk processes related to heavy drinking that could inform alcohol-related interventions for this population. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  10. Naltrexone Injection

    MedlinePlus

    Naltrexone injection is used along with counseling and social support to help people who have stopped drinking ... injection is also used along with counseling and social support to help people who have stopped abusing ...

  11. Trial of Naltrexone and Dextromethorphan for Gulf War Veterans’ Illness

    DTIC Science & Technology

    2015-07-01

    1 Award Number: W81XWH-09-2-0065 TITLE: Trial of Naltrexone and Dextromethorphan for Gulf War Veterans’ Illness PRINCIPAL INVESTIGATOR: William J... Dextromethorphan for Gulf War Veterans’ Illness 5a. CONTRACT NUMBER W81XWH-09-2-0065 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) William...is related to low grade neuron-inflammation, which can be down regulated, by Naltrexone and Dextromethorphan . This is untested but potentially

  12. Transcriptome profile analysis reflects rat liver and kidney damage following chronic ultra-low dose Roundup exposure.

    PubMed

    Mesnage, Robin; Arno, Matthew; Costanzo, Manuela; Malatesta, Manuela; Séralini, Gilles-Eric; Antoniou, Michael N

    2015-08-25

    Glyphosate-based herbicides (GBH) are the major pesticides used worldwide. Converging evidence suggests that GBH, such as Roundup, pose a particular health risk to liver and kidneys although low environmentally relevant doses have not been examined. To address this issue, a 2-year study in rats administering 0.1 ppb Roundup (50 ng/L glyphosate equivalent) via drinking water (giving a daily intake of 4 ng/kg bw/day of glyphosate) was conducted. A marked increased incidence of anatomorphological and blood/urine biochemical changes was indicative of liver and kidney structure and functional pathology. In order to confirm these findings we have conducted a transcriptome microarray analysis of the liver and kidneys from these same animals. The expression of 4224 and 4447 transcript clusters (a group of probes corresponding to a known or putative gene) were found to be altered respectively in liver and kidney (p < 0.01, q < 0.08). Changes in gene expression varied from -3.5 to 3.7 fold in liver and from -4.3 to 5.3 in kidneys. Among the 1319 transcript clusters whose expression was altered in both tissues, ontological enrichment in 3 functional categories among 868 genes were found. First, genes involved in mRNA splicing and small nucleolar RNA were mostly upregulated, suggesting disruption of normal spliceosome activity. Electron microscopic analysis of hepatocytes confirmed nucleolar structural disruption. Second, genes controlling chromatin structure (especially histone-lysine N-methyltransferases) were mostly upregulated. Third, genes related to respiratory chain complex I and the tricarboxylic acid cycle were mostly downregulated. Pathway analysis suggests a modulation of the mTOR and phosphatidylinositol signalling pathways. Gene disturbances associated with the chronic administration of ultra-low dose Roundup reflect a liver and kidney lipotoxic condition and increased cellular growth that may be linked with regeneration in response to toxic effects causing damage

  13. Biphasic and triphasic dose responses in zebrafish embryos to low-dose 150 kV X-rays with different levels of hardness.

    PubMed

    Kong, Eva Yi; Cheng, Shuk Han; Yu, Kwan Ngok

    2016-07-01

    The in vivo low-dose responses of zebrafish (Danio rerio) embryos to 150 kV X-rays with different levels of hardness were examined through the number of apoptotic events revealed at 24 h post fertilization by vital dye acridine orange staining. Our results suggested that a triphasic dose response was likely a common phenomenon in living organisms irradiated by X-rays, which comprised an ultra-low-dose inhibition, low-dose stimulation and high-dose inhibition. Our results also suggested that the hormetic zone (or the stimulation zone) was shifted towards lower doses with application of filters. The non-detection of a triphasic dose response in previous experiments could likely be attributed to the use of hard X-rays, which shifted the hormetic zone into an unmonitored ultra-low-dose region. In such cases where the subhormetic zone was missed, a biphasic dose response would be reported instead. © The Author 2016. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  14. SU-F-J-45: Sparing Normal Tissue with Ultra-High Dose Rate in Radiation Therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Feng, Y

    Purpose: To spare normal tissue by reducing the location uncertainty of a moving target, we proposed an ultra-high dose rate system and evaluated. Methods: High energy electrons generated with a linear accelerator were injected into a storage ring to be accumulated. The number of the electrons in the ring was determined based on the prescribed radiation dose. The dose was delivered within a millisecond, when an online imaging system found that the target was in the position that was consistent with that in a treatment plan. In such a short time period, the displacement of the target was negligible. Themore » margin added to the clinical target volume (CTV) could be reduced that was evaluated by comparing of volumes between CTV and ITV in 14 cases of lung stereotactic body radiation therapy (SBRT) treatments. A design of the ultra-high dose rate system was evaluated based clinical needs and the recent developments of low energy (a few MeV) electron storage ring. Results: This design of ultra-high dose rate system was feasible based on the techniques currently available. The reduction of a target volume was significant by reducing the margin that accounted the motion of the target. ∼50% volume reduction of the internal target volume (ITV) could be achieved in lung SBRT treatments. Conclusion: With this innovation of ultra-high dose rate system, the margin of target is able to be significantly reduced. It will reduce treatment time of gating and allow precisely specified gating window to improve the accuracy of dose delivering.« less

  15. Synthesis of Novel Basic Skeletons Derived from Naltrexone

    NASA Astrophysics Data System (ADS)

    Nagase, Hiroshi; Fujii, Hideaki

    We will describe eight interesting reactions using naltrexone derivatives. Almost all these reactions are characteristic of naltrexone derivatives, and can lead to the synthesis of many novel skeletons that provide new interesting pharmacological data. Some of the new reactions that were found with naltrexone derivatives were expanded into general reactions. For example, the reaction of 6α-hydroxyaldehyde derived from naltrexone led to the oxazoline dimer and the 1,3,5-trioxazatriquinane skeleton (triplet drug); this reaction was applied to general ketones which were converted to α-hydroxyaldehydes, followed by conversion to dimers and trimers, as described in Sect. 7.

  16. THE EFFECTS OF DRONABINOL DURING DETOXIFICATION AND THE INITIATION OF TREATMENT WITH EXTENDED RELEASE NALTREXONE

    PubMed Central

    Bisaga, Adam; Sullivan, Maria A.; Glass, Andrew; Mishlen, Kaitlyn; Pavlicova, Martina; Haney, Margaret; Raby, Wilfrid N.; Levin, Frances R.; Carpenter, Kenneth M.; Mariani, John J.; Nunes, Edward V.

    2015-01-01

    Background Evidence suggests that the cannabinoid system is involved in the maintenance of opioid dependence. We examined whether dronabinol, a cannabinoid receptor type 1 partial agonist, reduces opioid withdrawal and increases retention in treatment with extended release naltrexone (XR-naltrexone). Methods Opioid dependent participants were randomized to receive dronabinol 30 mg/d (n=40) or placebo (n=20), under double-blind conditions, while they underwent inpatient detoxification and naltrexone induction. Before discharge all participants received an injection of XR-naltrexone, with an additional dose given four weeks later. Dronabinol or placebo was given while inpatient and for 5 weeks afterwards. The primary outcomes were the severity of opioid withdrawal, measured with the Subjective Opioid Withdrawal Scale, and retention in treatment at the end of the inpatient phase and at the end of the 8-week trial. Results The severity of opioid withdrawal during inpatient phase was lower in the dronabinol group relative to placebo group (p=0.006). Rates of successful induction onto XR-naltrexone (dronabinol 66%, placebo 55%) and completion of treatment (dronabinol 35%, placebo 35%) were not significantly different. Post-hoc analysis showed that the 32% of participants who smoked marijuana regularly during the outpatient phase had significantly lower ratings of insomnia and anxiety and were more likely to complete the 8-week trial. Conclusion Dronabinol reduced the severity of opiate withdrawal during acute detoxification but had no effect on rates of XR-naltrexone treatment induction and retention. Participants who elected to smoke marijuana during the trial were more likely to complete treatment regardless of treatment group assignment. PMID:26187456

  17. Daily relations among affect, urge, targeted naltrexone, and alcohol use in young adults

    PubMed Central

    Bold, Krysten W.; Fucito, Lisa M.; Corbin, William R.; DeMartini, Kelly S.; Leeman, Robert F.; Kranzler, Henry R.; O’Malley, Stephanie S.

    2016-01-01

    Heavy drinking among young adults is a serious public health problem. Naltrexone, an opioid antagonist, has been shown to reduce drinking in young adults compared to placebo and can be taken on a targeted (i.e., as needed) basis. Understanding risk factors for drinking and naltrexone effects within-person in young adults may help to optimize the use of targeted naltrexone. The current study was a secondary analysis of daily diary data from 127 (n=40 female) young adults (age 18-25) enrolled in a double-blind clinical trial of daily (25 mg) plus targeted (25 mg) naltrexone versus placebo. Hierarchical linear models were used to examine the effects of daily affect, urge, and taking targeted medication on same-day risk of drinking to intoxication (defined as estimated blood-alcohol-concentration, BAC≥.08g%). Results indicated urge significantly mediated within-person positive affect–drinking relations on a daily level. Specifically, positive affect was associated with greater urge to drink, which in turn was associated with greater odds of BAC≥.08g%. Furthermore, days of greater positive affect and urge were associated with taking a targeted dose of medication, which reduced the likelihood of intoxication by nearly 23% in the naltrexone group compared to placebo. Gender and family history of alcohol dependence were examined as moderators of these daily level effects. These results provide further evidence of naltrexone’s ability to reduce alcohol consumption in young adults and identify potential within-person risk processes related to heavy drinking that could inform alcohol-related interventions for this population. PMID:27690505

  18. Separate and combined impact of acute naltrexone and alprazolam on subjective and physiological effects of oral d-amphetamine in stimulant users.

    PubMed

    Marks, Katherine R; Lile, Joshua A; Stoops, William W; Rush, Craig R

    2014-07-01

    Opioid antagonists (e.g., naltrexone) and positive modulators of γ-aminobutyric-acidA (GABAA) receptors (e.g., alprazolam) modestly attenuate the abuse-related effects of stimulants like amphetamine. The use of higher doses to achieve greater efficacy is precluded by side effects. Combining naltrexone and alprazolam might safely maximize efficacy while avoiding the untoward effects of the constituent compounds. The present pilot study tested the hypothesis that acute pretreatment with the combination of naltrexone and alprazolam would not produce clinically problematic physiological effects or negative subjective effects and would reduce the positive subjective effects of d-amphetamine to a greater extent than the constituent drugs alone. Eight nontreatment-seeking, stimulant-using individuals completed an outpatient experiment in which oral d-amphetamine (0, 15, and 30 mg) was administered following acute pretreatment with naltrexone (0 and 50 mg) and alprazolam (0 and 0.5 mg). Subjective effects, psychomotor task performance, and physiological measures were collected. Oral d-amphetamine produced prototypical physiological and stimulant-like positive subjective effects (e.g., VAS ratings of Active/Alert/Energetic, Good Effect, and High). Pretreatment with naltrexone, alprazolam, and their combination did not produce clinically problematic acute physiological effects or negative subjective effects. Naltrexone and alprazolam each significantly attenuated some of the subjective effects of d-amphetamine. The combination attenuated a greater number of subjective effects than the constituent drugs alone. The present results support the continued evaluation of an opioid receptor antagonist combined with a GABAA-positive modulator using more clinically relevant experimental conditions like examining the effect of chronic dosing with these drugs on methamphetamine self-administration.

  19. Submillisievert standard-pitch CT pulmonary angiography with ultra-low dose contrast media administration: A comparison to standard CT imaging.

    PubMed

    Suntharalingam, Saravanabavaan; Mikat, Christian; Stenzel, Elena; Erfanian, Youssef; Wetter, Axel; Schlosser, Thomas; Forsting, Michael; Nassenstein, Kai

    2017-01-01

    To evaluate the image quality and radiation dose of submillisievert standard-pitch CT pulmonary angiography (CTPA) with ultra-low dose contrast media administration in comparison to standard CTPA. Hundred patients (56 females, 44 males, mean age 69.6±15.4 years; median BMI: 26.6, IQR: 5.9) with suspected pulmonary embolism were examined with two different protocols (n = 50 each, group A: 80 kVp, ref. mAs 115, 25 ml of contrast medium; group B: 100 kVp, ref. mAs 150, 60 ml of contrast medium) using a dual-source CT equipped with automated exposure control. Objective and subjective image qualities, radiation exposure as well as the frequency of pulmonary embolism were evaluated. There was no significant difference in subjective image quality scores between two groups regarding pulmonary arteries (p = 0.776), whereby the interobserver agreement was excellent (group A: k = 0.9; group B k = 1.0). Objective image analysis revealed that signal intensities (SI), signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the pulmonary arteries were equal or significantly higher in group B. There was no significant difference in the frequency of pulmonary embolism (p = 0.65). Using the low dose and low contrast media protocol resulted in a radiation dose reduction by 71.8% (2.4 vs. 0.7 mSv; p<0.001). This 80 kVp standard pitch CTPA protocol with 25 ml contrast agent volume can obtain sufficient image quality to exclude or diagnose pulmonary emboli while reducing radiation dose by approximately 71%.

  20. The opioid growth factor (OGF) and low dose naltrexone (LDN) suppress human ovarian cancer progression in mice.

    PubMed

    Donahue, Renee N; McLaughlin, Patricia J; Zagon, Ian S

    2011-08-01

    The opioid growth factor (OGF) and its receptor, OGFr, serve as a tonically active inhibitory axis regulating cell proliferation in normal cells and a variety of cancers, including human ovarian cancer. Blockade of OGF and OGFr with the nonselective opioid receptor antagonist naltrexone (NTX) upregulates expression of OGF and OGFr. Administration of a low dosage of NTX (LDN) blocks endogenous opioids from opioid receptors for a short period of time (4-6 h) each day, providing a window of 18-20 h for the upregulated opioids and receptors to interact. The present study investigated the repercussions of upregulating the OGF-OGFr axis by treatment with OGF or LDN on human ovarian tumorigenesis in vivo. Female nude mice were transplanted intraperitoneally with SKOV-3 human ovarian cancer cells and treated on a daily basis with OGF (10 mg/kg), LDN (0.1 mg/kg), or an equivalent volume of vehicle (saline). Tumor burden, as well as DNA synthesis, apoptosis, and angiogenesis was assessed in tumor tissue following 40 days of treatment. OGF and LDN markedly reduced ovarian tumor burden (tumor nodule number and weight). The mechanism of action was targeted to an inhibition of tumor cell proliferation and angiogenesis; no changes in cell survival were noted. This study shows that a native opioid pathway can suppress human ovarian cancer in a xenograft model, and provides novel non-toxic therapies for the treatment of this lethal neoplasia. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Reduction of Alcohol Drinking in Young Adults by Naltrexone: A Double-Blind, Placebo-Controlled, Randomized Clinical Trial of Efficacy and Safety

    PubMed Central

    O’Malley, Stephanie S.; Corbin, William R.; Leeman, Robert F.; DeMartini, Kelly S.; Fucito, Lisa M.; Ikomi, Jolomi; Romano, Denise M.; Wu, Ran; Toll, Benjamin A.; Sher, Kenneth J.; Gueorguieva, Ralitza; Kranzler, Henry R.

    2015-01-01

    Objective Naltrexone, an opioid antagonist, may facilitate reduction in drinking among young adults. We compared the efficacy and safety of naltrexone administered daily plus targeted dosing with placebo to reduce drinking in heavy drinking young adults. Methods Randomized, double-blind, placebo-controlled study, outpatient research center, March 2008-January 2012. Participants were ages 18-25, reporting ≥ 4 heavy drinking days in the prior 4 weeks. Interventions included naltrexone 25 mg daily plus 25 mg targeted (at most daily) in anticipation of drinking (n = 61) or daily/targeted placebo (n = 67). All received a personalized feedback session and brief counseling every other week. Primary outcomes were percent days heavy drinking (PHDD) and percent days abstinent (PDA) over the 8-week treatment period. Secondary outcomes included drinks/drinking day and percent days with estimated blood alcohol levels ≥0.08 g/dL. Results Of 140 randomized, 128 began treatment, comprising the evaluable sample. During treatment, PHDD (Naltrexone M=21.60, SD=16.05; Placebo M=22.90, SD=13.20) (p=0.58) and PDA (Naltrexone M=56.60, SD=22.52; Placebo M=62.50, SD=15.75) (p=0.39) did not differ by group. Naltrexone significantly reduced drinks per drinking day (Naltrexone M=4.90, SD=2.28; Placebo M=5.90, SD=2.51) (p=0.009) and percentage of drinking days with estimated BAC ≥0.08 g/dL (Naltrexone M=35.36, SD=28.40; Placebo M=45.74, SD=26.80) (p=0.042). There were no serious adverse events. Sleepiness was more common with naltrexone. Conclusions Naltrexone did not reduce frequency of drinking or heavy drinking days, but reduced secondary measures of drinking intensity. While effects were modest, the risk-benefit ratio favors offering naltrexone to help young adult heavy drinkers reduce their drinking. Registration clinicaltrials.gov NCT00568958 PMID:25742208

  2. Favorable mortality profile of naltrexone implants for opiate addiction.

    PubMed

    Reece, Albert Stuart

    2010-01-01

    Several reports express concern at the mortality associated with the use of oral naltrexone for opiate dependency. Registry controlled follow-up of patients treated with naltrexone implant and buprenorphine was performed. In the study, 255 naltrexone implant patients were followed for a mean (+/- standard deviation) of 5.22 +/- 1.87 years and 2,518 buprenorphine patients were followed for a mean (+/- standard deviation) of 3.19 +/- 1.61 years, accruing 1,332.22 and 8,030.02 patient-years of follow-up, respectively. The crude mortality rates were 3.00 and 5.35 per 1,000 patient-years, respectively, and the age standardized mortality rate ratio for naltrexone compared to buprenorphine was 0.676 (95% confidence interval = 0.014 to 1.338). Most sex, treatment group, and age comparisons significantly favored the naltrexone implant group. Mortality rates were shown to be comparable to, and intermediate between, published mortality rates of an age-standardized methadone treated cohort and the Australian population. These data suggest that the mortality rate from naltrexone implant is comparable to that of buprenorphine, methadone, and the Australian population.

  3. Ultra-low-dose lung screening CT with model-based iterative reconstruction: an assessment of image quality and lesion conspicuity.

    PubMed

    Ju, Yun Hye; Lee, Geewon; Lee, Ji Won; Hong, Seung Baek; Suh, Young Ju; Jeong, Yeon Joo

    2018-05-01

    Background Reducing radiation dose inevitably increases image noise, and thus, it is important in low-dose computed tomography (CT) to maintain image quality and lesion detection performance. Purpose To assess image quality and lesion conspicuity of ultra-low-dose CT with model-based iterative reconstruction (MBIR) and to determine a suitable protocol for lung screening CT. Material and Methods A total of 120 heavy smokers underwent lung screening CT and were randomly and equally assigned to one of five groups: group 1 = 120 kVp, 25 mAs, with FBP reconstruction; group 2 = 120 kVp, 10 mAs, with MBIR; group 3 = 100 kVp, 15 mAs, with MBIR; group 4 = 100 kVp, 10 mAs, with MBIR; and group 5 = 100 kVp, 5 mAs, with MBIR. Two radiologists evaluated intergroup differences with respect to radiation dose, image noise, image quality, and lesion conspicuity using the Kruskal-Wallis test and the Chi-square test. Results Effective doses were 61-87% lower in groups 2-5 than in group 1. Image noises in groups 1 and 5 were significantly higher than in the other groups ( P < 0.001). Overall image quality was best in group 1, but diagnostic acceptability of overall image qualities in groups 1-3 was not significantly different (all P values > 0.05). Lesion conspicuities were similar in groups 1-4, but were significantly poorer in group 5. Conclusion Lung screening CT with MBIR obtained at 100 kVp and 15 mAs enables a ∼60% reduction in radiation dose versus low-dose CT, while maintaining image quality and lesion conspicuity.

  4. Does naltrexone affect craving in abstinent opioid-dependent patients?

    PubMed

    Dijkstra, Boukje A G; De Jong, Cor A J; Bluschke, Sarah M; Krabbe, Paul F M; van der Staak, Cees P F

    2007-06-01

    Naltrexone blocks the opioid receptors that modulate the release of dopamine in the brain reward system and therefore blocks the rewarding effects of heroin and alcohol. It is generally assumed that naltrexone leads to reduction of craving, but few studies have been performed to prove this. The purpose of the present study was to examine the effect of the administration of naltrexone on craving level after rapid opioid detoxification induced by naltrexone. A naturalistic study was carried out in which patients were followed during 10 months after rapid detoxification. Data about abstinence, relapse, and naltrexone use were collected by means of urine specimens. Craving was measured by the visual analogue scale craving, the Obsessive Compulsive Drug Use Scale, and the Desires for Drug Questionnaire. Results showed that patients who relapsed in opioid use experienced obviously more craving than abstinent people. Patients who took naltrexone did not experience significant less craving than those who did not. These results suggest that the use of opioids is associated with increased craving and that abstinence for opioids is associated with less craving, independent of the use of naltrexone. This is in contrast to the general opinion. Because of the naturalistic design of the study, no firm conclusions can be drawn, but the results grounded the needs of an experimental study.

  5. Adaptive Statistical Iterative Reconstruction-Applied Ultra-Low-Dose CT with Radiography-Comparable Radiation Dose: Usefulness for Lung Nodule Detection.

    PubMed

    Yoon, Hyun Jung; Chung, Myung Jin; Hwang, Hye Sun; Moon, Jung Won; Lee, Kyung Soo

    2015-01-01

    To assess the performance of adaptive statistical iterative reconstruction (ASIR)-applied ultra-low-dose CT (ULDCT) in detecting small lung nodules. Thirty patients underwent both ULDCT and standard dose CT (SCT). After determining the reference standard nodules, five observers, blinded to the reference standard reading results, independently evaluated SCT and both subsets of ASIR- and filtered back projection (FBP)-driven ULDCT images. Data assessed by observers were compared statistically. Converted effective doses in SCT and ULDCT were 2.81 ± 0.92 and 0.17 ± 0.02 mSv, respectively. A total of 114 lung nodules were detected on SCT as a standard reference. There was no statistically significant difference in sensitivity between ASIR-driven ULDCT and SCT for three out of the five observers (p = 0.678, 0.735, < 0.01, 0.038, and < 0.868 for observers 1, 2, 3, 4, and 5, respectively). The sensitivity of FBP-driven ULDCT was significantly lower than that of ASIR-driven ULDCT in three out of the five observers (p < 0.01 for three observers, and p = 0.064 and 0.146 for two observers). In jackknife alternative free-response receiver operating characteristic analysis, the mean values of figure-of-merit (FOM) for FBP, ASIR-driven ULDCT, and SCT were 0.682, 0.772, and 0.821, respectively, and there were no significant differences in FOM values between ASIR-driven ULDCT and SCT (p = 0.11), but the FOM value of FBP-driven ULDCT was significantly lower than that of ASIR-driven ULDCT and SCT (p = 0.01 and 0.00). Adaptive statistical iterative reconstruction-driven ULDCT delivering a radiation dose of only 0.17 mSv offers acceptable sensitivity in nodule detection compared with SCT and has better performance than FBP-driven ULDCT.

  6. Adaptive Statistical Iterative Reconstruction-Applied Ultra-Low-Dose CT with Radiography-Comparable Radiation Dose: Usefulness for Lung Nodule Detection

    PubMed Central

    Yoon, Hyun Jung; Hwang, Hye Sun; Moon, Jung Won; Lee, Kyung Soo

    2015-01-01

    Objective To assess the performance of adaptive statistical iterative reconstruction (ASIR)-applied ultra-low-dose CT (ULDCT) in detecting small lung nodules. Materials and Methods Thirty patients underwent both ULDCT and standard dose CT (SCT). After determining the reference standard nodules, five observers, blinded to the reference standard reading results, independently evaluated SCT and both subsets of ASIR- and filtered back projection (FBP)-driven ULDCT images. Data assessed by observers were compared statistically. Results Converted effective doses in SCT and ULDCT were 2.81 ± 0.92 and 0.17 ± 0.02 mSv, respectively. A total of 114 lung nodules were detected on SCT as a standard reference. There was no statistically significant difference in sensitivity between ASIR-driven ULDCT and SCT for three out of the five observers (p = 0.678, 0.735, < 0.01, 0.038, and < 0.868 for observers 1, 2, 3, 4, and 5, respectively). The sensitivity of FBP-driven ULDCT was significantly lower than that of ASIR-driven ULDCT in three out of the five observers (p < 0.01 for three observers, and p = 0.064 and 0.146 for two observers). In jackknife alternative free-response receiver operating characteristic analysis, the mean values of figure-of-merit (FOM) for FBP, ASIR-driven ULDCT, and SCT were 0.682, 0.772, and 0.821, respectively, and there were no significant differences in FOM values between ASIR-driven ULDCT and SCT (p = 0.11), but the FOM value of FBP-driven ULDCT was significantly lower than that of ASIR-driven ULDCT and SCT (p = 0.01 and 0.00). Conclusion Adaptive statistical iterative reconstruction-driven ULDCT delivering a radiation dose of only 0.17 mSv offers acceptable sensitivity in nodule detection compared with SCT and has better performance than FBP-driven ULDCT. PMID:26357505

  7. Separate and combined impact of acute naltrexone and alprazolam on subjective and physiological effects of oral d-amphetamine in stimulant users

    PubMed Central

    Marks, Katherine R.; Lile, Joshua A.; Stoops, William W.

    2014-01-01

    Rationale Opioid antagonists (e.g., naltrexone) and positive modulators of γ-aminobutyric-acidA (GABAA) receptors (e.g., alprazolam) modestly attenuate the abuse-related effects of stimulants like amphetamine. The use of higher doses to achieve greater efficacy is precluded by side effects. Combining naltrexone and alprazolam might safely maximize efficacy while avoiding the untoward effects of the constituent compounds. Objectives The present pilot study tested the hypothesis that acute pretreatment with the combination of naltrexone and alprazolam would not produce clinically problematic physiological effects or negative subjective effects and would reduce the positive subjective effects of d-amphetamine to a greater extent than the constituent drugs alone. Methods Eight nontreatment-seeking, stimulant-using individuals completed an outpatient experiment in which oral d-amphetamine (0, 15, and 30 mg) was administered following acute pretreatment with naltrexone (0 and 50 mg) and alprazolam (0 and 0.5 mg). Subjective effects, psychomotor task performance, and physiological measures were collected. Results Oral d-amphetamine produced prototypical physiological and stimulant-like positive subjective effects (e.g., VAS ratings of Active/Alert/Energetic, Good Effect, and High). Pretreatment with naltrexone, alprazolam, and their combination did not produce clinically problematic acute physiological effects or negative subjective effects. Naltrexone and alprazolam each significantly attenuated some of the subjective effects of d-amphetamine. The combination attenuated a greater number of subjective effects than the constituent drugs alone. Conclusions The present results support the continued evaluation of an opioid receptor antagonist combined with a GABAA-positive modulator using more clinically relevant experimental conditions like examining the effect of chronic dosing with these drugs on methamphetamine self-administration. PMID:24464531

  8. Submillisievert standard-pitch CT pulmonary angiography with ultra-low dose contrast media administration: A comparison to standard CT imaging

    PubMed Central

    Mikat, Christian; Stenzel, Elena; Erfanian, Youssef; Wetter, Axel; Schlosser, Thomas; Forsting, Michael

    2017-01-01

    Objectives To evaluate the image quality and radiation dose of submillisievert standard-pitch CT pulmonary angiography (CTPA) with ultra-low dose contrast media administration in comparison to standard CTPA. Materials and methods Hundred patients (56 females, 44 males, mean age 69.6±15.4 years; median BMI: 26.6, IQR: 5.9) with suspected pulmonary embolism were examined with two different protocols (n = 50 each, group A: 80 kVp, ref. mAs 115, 25 ml of contrast medium; group B: 100 kVp, ref. mAs 150, 60 ml of contrast medium) using a dual-source CT equipped with automated exposure control. Objective and subjective image qualities, radiation exposure as well as the frequency of pulmonary embolism were evaluated. Results There was no significant difference in subjective image quality scores between two groups regarding pulmonary arteries (p = 0.776), whereby the interobserver agreement was excellent (group A: k = 0.9; group B k = 1.0). Objective image analysis revealed that signal intensities (SI), signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the pulmonary arteries were equal or significantly higher in group B. There was no significant difference in the frequency of pulmonary embolism (p = 0.65). Using the low dose and low contrast media protocol resulted in a radiation dose reduction by 71.8% (2.4 vs. 0.7 mSv; p<0.001). Conclusions This 80 kVp standard pitch CTPA protocol with 25 ml contrast agent volume can obtain sufficient image quality to exclude or diagnose pulmonary emboli while reducing radiation dose by approximately 71%. PMID:29045463

  9. Opposing neural effects of naltrexone on food reward and aversion: implications for the treatment of obesity.

    PubMed

    Murray, Elizabeth; Brouwer, Sietske; McCutcheon, Rob; Harmer, Catherine J; Cowen, Philip J; McCabe, Ciara

    2014-11-01

    Opioid antagonism reduces the consumption of palatable foods in humans but the neural substrates implicated in these effects are less well understood. The aim of the present study was to examine the effects of the opioid antagonist, naltrexone, on neural response to rewarding and aversive sight and taste stimuli. We used functional magnetic resonance imaging (fMRI) to examine the neural responses to the sight and taste of pleasant (chocolate) and aversive (mouldy strawberry) stimuli in 20 healthy volunteers who received a single oral dose of naltrexone (50 mg) and placebo in a double-blind, repeated-measures cross-over, design. Relative to placebo, naltrexone decreased reward activation to chocolate in the dorsal anterior cingulate cortex and caudate, and increased aversive-related activation to unpleasant strawberry in the amygdala and anterior insula. These findings suggest that modulation of key brain areas involved in reward processing, cognitive control and habit formation such as the dorsal anterior cingulate cortex (dACC) and caudate might underlie reduction in food intake with opioid antagonism. Furthermore we show for the first time that naltrexone can increase activations related to aversive food stimuli. These results support further investigation of opioid treatments in obesity.

  10. A low-cost, ultra-fast and ultra-low noise preamplifier for silicon avalanche photodiodes

    NASA Astrophysics Data System (ADS)

    Gasmi, Khaled

    2018-02-01

    An ultra-fast and ultra-low noise preamplifier for amplifying the fast and weak electrical signals generated by silicon avalanche photodiodes has been designed and developed. It is characterized by its simplicity, compactness, reliability and low cost of construction. A very wide bandwidth of 300 MHz, a very good linearity from 1 kHz to 280 MHz, an ultra-low noise level at the input of only 1.7 nV Hz-1/2 and a very good stability are its key features. The compact size (70 mm  ×  90 mm) and light weight (45 g), as well as its excellent characteristics, make this preamplifier very competitive compared to any commercial preamplifier. The preamplifier, which is a main part of the detection system of a homemade laser remote sensing system, has been successfully tested. In addition, it is versatile and can be used in any optical detection system requiring high speed and very low noise electronics.

  11. [Limited role of naltrexone in the treatment of opiate addiction].

    PubMed

    van Brussel, G H

    2001-07-28

    Naltrexone has been used for many years as an opiate antagonist for maintenance treatment to prevent relapse in opiate addiction and, more recently, for rapid opiate detoxification with and without general anaesthesia. Naltrexone is useful for rapid detoxification without anaesthesia. However, the detoxification procedure under anaesthesia lacks a scientific basis. There is no clear evidence of the efficacy of naltrexone maintenance treatment. Poor compliance and possible receptor sensitisation means there may be a potentially increased risk of mortality through opiate overdose following cessation of naltrexone treatment and relapse into addiction.

  12. Clonidine hydrochloride detoxification from methadone treatment--the value of naltrexone aftercare.

    PubMed

    Rawson, R A; Washton, A M; Resnick, R B; Tennant, F S

    1984-01-01

    Treatment outcomes were compared for 2 groups of subjects detoxified from methadone using clonidine. One group of 12 subjects was encouraged to continue in treatment with naltrexone, while the other 12 subjects did not have naltrexone treatment available. Results suggested that those subjects who had naltrexone available were more successful at completing the 10 day detoxification treatment and that the relapse rate at 30 days post-treatment was significantly reduced by naltrexone treatment.

  13. Employment-based reinforcement of adherence to an FDA approved extended release formulation of naltrexone in opioid-dependent adults: a randomized controlled trial.

    PubMed

    DeFulio, Anthony; Everly, Jeffrey J; Leoutsakos, Jeannie-Marie S; Umbricht, Annie; Fingerhood, Michael; Bigelow, George E; Silverman, Kenneth

    2012-01-01

    Naltrexone provides excellent opioid blockade, but its clinical utility is limited because opioid-dependent patients typically refuse it. An injectable suspension of naltrexone for extended release (XR-NTX) was recently approved by the FDA for treatment of opioid dependence. XR-NTX treatment may require concurrent behavioral intervention to maximize adherence and effectiveness, thus we sought to evaluate employment-based reinforcement as a method of improving adherence to XR-NTX in opiate dependent adults. Opioid-dependent adults (n=38) were detoxified and inducted onto oral naltrexone, then randomly assigned to contingency or prescription conditions. Participants received up to six doses of XR-NTX at four-week intervals. All participants could earn vouchers for attendance and performance at a therapeutic workplace. Contingency participants were required to accept XR-NTX injections to access the workplace and earn vouchers. Prescription participants could earn vouchers independent of their acceptance of XR-NTX injections. Contingency participants accepted significantly more naltrexone injections than prescription participants (87% versus 52%, p=.002), and were more likely to accept all injections (74% versus 26%, p=.004). Participants in the two conditions provided similar percentages of samples negative for opiates (72% versus 65%) and for cocaine (58% versus 54%). Opiate positivity was significantly more likely when samples were also cocaine positive, independent of naltrexone blockade (p=.002). Long-term adherence to XR-NTX in unemployed opiate dependent adults is low under usual care conditions. Employment-based reinforcement can maintain adherence to XR-NTX. Ongoing cocaine use appears to interfere with the clinical effectiveness of XR-NTX on opiate use. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  14. Outcome predictors for problem drinkers treated with combined cognitive behavioral therapy and naltrexone.

    PubMed

    Vuoristo-Myllys, Salla; Lipsanen, Jari; Lahti, Jari; Kalska, Hely; Alho, Hannu

    2014-03-01

    The opioid antagonist naltrexone, combined with cognitive behavioural therapy (CBT), has proven efficacious for patients with alcohol dependence, but studies examining how this treatment works in a naturalistic treatment setting are lacking. This study examined predictors of the outcome of targeted naltrexone and CBT in a real-life outpatient setting. Participants were 315 patients who attended a treatment program providing CBT combined with the targeted use of naltrexone. Mixture models for estimating developmental trajectories were used to examine change in patients' alcohol consumption and symptoms of alcohol craving from treatment entry until the end of the treatment (20 weeks) or dropout. Predictors of treatment outcome were examined with analyses of multinomial logistic regression. Minimal exclusion criteria were applied to enhance the generalizability of the findings. Regular drinking pattern, having no history of previous treatments, and high-risk alcohol consumption level before the treatment were associated with less change in alcohol use during the treatment. The patients with low-risk alcohol consumption level before the treatment had the most rapid reduction in alcohol craving. Patients who drank more alcohol during the treatment had lower adherence with naltrexone. Medication non-adherence is a major barrier to naltrexone's effectiveness in a real-life treatment setting. Patients with more severe alcohol problems may need more intensive treatment for achieving better treatment outcome in real-word treatment settings.

  15. Is multidetector CT-based bone mineral density and quantitative bone microstructure assessment at the spine still feasible using ultra-low tube current and sparse sampling?

    PubMed

    Mei, Kai; Kopp, Felix K; Bippus, Rolf; Köhler, Thomas; Schwaiger, Benedikt J; Gersing, Alexandra S; Fehringer, Andreas; Sauter, Andreas; Münzel, Daniela; Pfeiffer, Franz; Rummeny, Ernst J; Kirschke, Jan S; Noël, Peter B; Baum, Thomas

    2017-12-01

    Osteoporosis diagnosis using multidetector CT (MDCT) is limited to relatively high radiation exposure. We investigated the effect of simulated ultra-low-dose protocols on in-vivo bone mineral density (BMD) and quantitative trabecular bone assessment. Institutional review board approval was obtained. Twelve subjects with osteoporotic vertebral fractures and 12 age- and gender-matched controls undergoing routine thoracic and abdominal MDCT were included (average effective dose: 10 mSv). Ultra-low radiation examinations were achieved by simulating lower tube currents and sparse samplings at 50%, 25% and 10% of the original dose. BMD and trabecular bone parameters were extracted in T10-L5. Except for BMD measurements in sparse sampling data, absolute values of all parameters derived from ultra-low-dose data were significantly different from those derived from original dose images (p<0.05). BMD, apparent bone fraction and trabecular thickness were still consistently lower in subjects with than in those without fractures (p<0.05). In ultra-low-dose scans, BMD and microstructure parameters were able to differentiate subjects with and without vertebral fractures, suggesting osteoporosis diagnosis is feasible. However, absolute values differed from original values. BMD from sparse sampling appeared to be more robust. This dose-dependency of parameters should be considered for future clinical use. • BMD and quantitative bone parameters are assessable in ultra-low-dose in vivo MDCT scans. • Bone mineral density does not change significantly when sparse sampling is applied. • Quantitative trabecular bone microstructure measurements are sensitive to dose reduction. • Osteoporosis subjects could be differentiated even at 10% of original dose. • Radiation exposure should be considered when comparing quantitative bone parameters.

  16. Alterations of naltrexone-induced conditioned place avoidance by pre-exposure to high fructose corn syrup or heroin in Sprague-Dawley rats.

    PubMed

    Daniels, Stephen; Marshall, Paul; Leri, Francesco

    2016-02-01

    It has been suggested that withdrawal from sugar produces a set of symptoms that resemble those observed following withdrawal from opiate drugs. This study explored naltrexone-induced withdrawal in animals pre-exposed to acute, chronic, and intermittent high fructose corn syrup (HFCS) or acute and chronic heroin administration. Experiment 1 examined conditioned place avoidance (CPA) induced by different doses of naltrexone (0.01-1 mg/kg) in naïve male Sprague-Dawley rats. In experiment 2, rats received continuous or intermittent home cage HFCS access (0 or 50 %) prior to conditioning with 1 mg/kg naltrexone. In experiment 3, HFCS ingestion was increased by food restriction and rats were conditioned with 3 mg/kg naltrexone. In experiment 4, the timing and quantity of HFCS ingestion (0, 0.5, 1, 2 g/kg) was controlled by intragastric administration, and rats were conditioned with 1 mg/kg naltrexone. In experiment 5, rats received acute (2 mg/kg) or chronic heroin (3.5 mg/kg/day) prior to conditioning with 1 mg/kg naltrexone. Administration of naltrexone produced moderate conditioned place avoidance in naïve rats. Importantly, acute, continuous, and intermittent HFCS pre-exposure did not significantly amplify this effect, but acute and chronic heroin pre-exposure did. As assessed by CPA, these results in rats fail to support the hypothesis that an opioid antagonist can precipitate similar affective withdrawal states following pre-exposure to sugars and opiates.

  17. Ultra-low Doses of Follicle Stimulating Hormone and Progesterone Attenuate the Severity of Polycystic Ovary Syndrome Features in a Hyperandrogenized Mouse Model

    PubMed Central

    Tessaro, Irene; Modina, Silvia; Lodde, Valentina; Sivelli, Giulia; Franciosi, Federica; Terzaghi, Laura; Luchini, Patrizia; Rumio, Cristiano; Luciano, Alberto Maria

    2017-01-01

    Background: Polycystic-ovary syndrome (PCOS) is a reproductive illness characterized by hyperandrogenism and anovulation. Using hyperandrogenized mice, it was demonstrated that the oral administration of incremental dose of follicle stimulating hormone (FSH) attenuated some of PCOS characteristics. This work aimed to study the effect of ultra-low doses of combined FSH and progesterone orally administered on PCOS murine model. Moreover, the effect of sequential kinetic activation of administered hormones was tested. Methods: Thirty-two female mice were used as animal model (four groups of eight animals each). Mice were hyperandrogenized by injection of dehyidroepiandrosterone diluted in sesame oil. Control group received only oil. Simultaneously, each animal daily received per os an activated or a not-activated combination of FSH (0.44 pg) plus progesterone (0.44 pg) or saline solution as control. Serum testosterone, estradiol, progesterone and luteinizing hormone were analyzed as endocrine markers and a morphological study of antral follicle was conducted. Data were analyzed by one-way ANOVA, followed by multiple comparison test. The p<0.05 was considered significant. Results: Dehyidroepiandrosterone treatment increased both estradiol and progesterone serum levels, besides testosterone, while reduced luteinizing hormone (p<0.05); histological examination revealed an increase of cystic follicles (p<0.05). Irrespective of activation, the combined FSH and progesterone treatments restored estradiol level (p>0.05 vs. control group) and reduced cystic signs in the follicles (p<0.05 vs. dehyidroepiandrosterone treatment). Conclusion: This study indicate that ultra-low doses of FSH and progesterone orally administrated can reduce the sternness of PCOS in the mouse model and open a route for the study of innovative approaches for PCOS treatment. PMID:29062793

  18. Effect of naltrexone plus bupropion on weight loss in overweight and obese adults (COR-I): a multicentre, randomised, double-blind, placebo-controlled, phase 3 trial.

    PubMed

    Greenway, Frank L; Fujioka, Ken; Plodkowski, Raymond A; Mudaliar, Sunder; Guttadauria, Maria; Erickson, Janelle; Kim, Dennis D; Dunayevich, Eduardo

    2010-08-21

    Despite increasing public health concerns regarding obesity, few safe and effective drug treatments are available. Combination treatment with sustained-release naltrexone and bupropion was developed to produce complementary actions in CNS pathways regulating bodyweight. The Contrave Obesity Research I (COR-I) study assessed the effect of such treatment on bodyweight in overweight and obese participants. Men and women aged 18-65 years who had a body-mass index (BMI) of 30-45 kg/m(2) and uncomplicated obesity or BMI 27-45 kg/m(2) with dyslipidaemia or hypertension were eligible for enrolment in this randomised, double-blind, placebo-controlled, phase 3 trial undertaken at 34 sites in the USA. Participants were prescribed mild hypocaloric diet and exercise and were randomly assigned in a 1:1:1 ratio to receive sustained-release naltrexone 32 mg per day plus sustained-release bupropion 360 mg per day combined in fixed-dose tablets (also known as NB32), sustained-release naltrexone 16 mg per day plus sustained-release bupropion 360 mg per day combined in fixed-dose tablets (also known as NB16), or matching placebo twice a day, given orally for 56 weeks. The trial included a 3-week dose escalation. Randomisation was done by use of a centralised, computer-generated, web-based system and was stratified by study centre. Co-primary efficacy endpoints at 56 weeks were percentage change in bodyweight and proportion of participants who achieved a decrease in bodyweight of 5% or more. The primary analysis included all randomised participants with a baseline weight measurement and a post-baseline weight measurement while on study drug (last observation carried forward). This study is registered with ClinicalTrials.gov, number NCT00532779. 1742 participants were enrolled and randomised to double-blind treatment (naltrexone 32 mg plus bupropion, n=583; naltrexone 16 mg plus bupropion, n=578; placebo, n=581). 870 (50%) participants completed 56 weeks of treatment (n=296; n=284; n

  19. Naltrexone ER/Bupropion ER: A Review in Obesity Management.

    PubMed

    Greig, Sarah L; Keating, Gillian M

    2015-07-01

    Oral naltrexone extended-release/bupropion extended-release (naltrexone ER/bupropion ER; Contrave(®), Mysimba(™)) is available as an adjunct to a reduced-calorie diet and increased physical activity in adults with an initial body mass index (BMI) of ≥ 30 kg/m(2) (i.e. obese) or a BMI of ≥ 27 kg/m(2) (i.e. overweight) in the presence of at least one bodyweight-related comorbidity, such as type 2 diabetes mellitus, hypertension or dyslipidaemia. In 56-week phase III trials in these patient populations, oral naltrexone ER/bupropion ER 32/360 mg/day was significantly more effective than placebo with regard to percentage bodyweight reductions from baseline and the proportion of patients who achieved bodyweight reductions of ≥ 5 and ≥ 10%. Significantly greater improvements in several cardiometabolic risk factors were also observed with naltrexone ER/bupropion ER versus placebo, as well as greater improvements in glycated haemoglobin levels in obese or overweight adults with type 2 diabetes. Naltrexone ER/bupropion ER was generally well tolerated in phase III trials, with nausea being the most common adverse event. Thus, naltrexone ER/bupropion ER 32/360 mg/day as an adjunct to a reduced-calorie diet and increased physical activity, is an effective and well tolerated option for chronic bodyweight management in obese adults or overweight adults with at least one bodyweight-related comorbidity.

  20. Predictors for the efficacy of naltrexone treatment in alcohol dependence: sweet preference.

    PubMed

    Laaksonen, E; Lahti, J; Sinclair, J D; Heinälä, P; Alho, H

    2011-01-01

    To analyse the possible associations between sweet preference and the efficacy of naltrexone treatment of alcohol dependence. The preference for different concentrations of sucrose was evaluated in 78 participants diagnosed with alcohol dependence after treatment for 32 weeks with naltrexone or placebo without prior detoxification. A significant difference between naltrexone and placebo groups was found in the association between the preference for higher sucrose concentrations and relapses to heavy drinking. Higher sweet preference was significantly related to successful treatment measures in the naltrexone group but not in the placebo group. Sweet preference has a strong correlation to treatment outcomes with naltrexone, and sweet preference might be used as a predictor for better treatment results in alcoholics. Our study offers one possible new explanation of the clinical observation that naltrexone is not effective for every patient.

  1. Baclofen and naltrexone effects on alcohol self-administration: Comparison of treatment initiated during abstinence or ongoing alcohol access in baboons.

    PubMed

    Holtyn, August F; Kaminski, Barbara J; Weerts, Elise M

    2017-10-01

    Baclofen, a GABA B receptor agonist, is under investigation as a pharmacotherapy for alcohol use disorder. Treatment with a pharmacotherapeutic can be initiated during alcohol abstinence or active drinking, which may influence treatment outcomes. This study examined whether baclofen treatment initiated and maintained during alcohol abstinence would reduce alcohol seeking and self-administration upon return to alcohol access, and whether effects differed from treatment initiated and maintained during ongoing alcohol access. Naltrexone was tested under similar conditions for comparison. Five baboons self-administered alcohol under a three-component chained schedule of reinforcement that modeled periods of anticipation (Component 1), seeking (Component 2), and consumption (Component 3). Alcohol was only available in Component 3. In Experiment 1, baclofen (0.1-1.8mg/kg) or naltrexone (1.0-5.6mg/kg) was administered daily beginning on the first day of a 5-day abstinence period and treatment was continued for 5days of alcohol access. In Experiment 2, selected doses of both drugs were administered during ongoing alcohol access. When treatment was initiated during alcohol abstinence, baclofen and naltrexone did not significantly reduce total alcohol intake (g/kg) or alcohol seeking. In comparison, when treatment was initiated during ongoing alcohol access, both baclofen (1.8mg/kg) and naltrexone (3.2 and 5.6mg/kg) significantly reduced total alcohol intake (g/kg). Naltrexone (5.6mg/kg), but not baclofen, significantly reduced alcohol seeking. Initiation of baclofen treatment (or other alcohol use disorder treatments) during abstinence or active drinking may be an important factor in influencing efficacy and appropriate dose selection. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Effects of amylin and bupropion/naltrexone on food intake and body weight are interactive in rodent models.

    PubMed

    Clapper, Jason R; Athanacio, Jennifer; Wittmer, Carrie; Griffin, Pete S; D'Souza, Lawrence; Parkes, David G; Roth, Jonathan D

    2013-01-05

    Antagonism of opioid systems (e.g., with naltrexone) has been explored as an anti-obesity strategy, and is particularly effective when co-administered with dual inhibitors of dopamine and norepinephrine reuptake (e.g., bupropion). Previously, we demonstrated that amylin enhances the food intake lowering and weight loss effects of neurohormonal (e.g., leptin, cholecystokinin, melanocortins) and small molecule (e.g., phentermine, sibutramine) agents. Here, we sought to characterize the interaction of amylin with naltrexone/bupropion on energy balance. Wild-type and amylin knockout mice were similarly responsive to the food intake lowering effects of either naltrexone (1mg/kg, subcutaneous) or bupropion (50mg/kg, subcutaneous) suggesting that they act independently of amylinergic systems and could interact additively when given in combination with amylin. To test this, diet-induced obese rats were treated (for 11 days) with vehicle, rat amylin (50 μg/kg/d, infused subcutaneously), naltrexone/bupropion (1 and 20mg/kg, respectively by twice daily subcutaneous injection) or their combination. We found that amylin+naltrexone/bupropion combination therapy exerted additive effects to reduce cumulative food intake, body weight and fat mass. In a separate study, the effects of amylin and naltrexone/bupropion administered at the same doses (for 14 days) were compared to a pair-fed group. Although the combination and pair-fed groups lost a similar amount of body weight, rats treated with the combination lost 68% more fat and better maintained their lean mass. These findings support the strategy of combined amylin agonism with opioid and catecholaminergic signaling systems for the treatment of obesity. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Sex differences in acute hormonal and subjective response to naltrexone: the impact of menstrual cycle phase

    PubMed Central

    Roche, Daniel J.O.; King, Andrea C.

    2015-01-01

    Women often exhibit larger hormonal and subjective responses to opioid receptor antagonists than men, but the biological mechanisms mediating this effect remain unclear. Among women, fluctuations in estradiol (E2) and progesterone (P4) across the menstrual cycle (MC) affect the endogenous opioid system. Therefore, the goal of the current study was to compare acute naltrexone response between women in the early follicular phase of the MC (low E2 and P4), women in the luteal phase of the MC (high E2 and P4), and men. Seventy healthy controls (n = 46 women) participated in two morning sessions in which they received 50 mg naltrexone or placebo in a randomized, counterbalanced order. Women were randomized to complete both sessions in either the early follicular (n = 23) or luteal phase of the MC. Serum cortisol, prolactin, and luteinizing hormone (LH), salivary cortisol, and subjective response were assessed upon arrival to the laboratory and at regular intervals after pill administration. In luteal and early follicular women but not men, naltrexone (vs. placebo) increased serum cortisol and prolactin levels from baseline; however, the naltrexone-induced increases in these hormones were significantly greater in luteal women than early follicular women. Additionally, only luteal women demonstrated an increase from baseline in salivary cortisol levels and the severity of adverse drug effects in response to naltrexone. In sum, the results indicate that luteal phase women are more sensitive to acute hormonal and subjective effects of naltrexone than early follicular women and men. These findings may have important implications for the use of naltrexone in women. PMID:25459893

  4. Effects of naltrexone on post-abstinence alcohol drinking in C57BL/6NCRL and DBA/2J mice.

    PubMed

    Tomie, Arthur; Azogu, Idu; Yu, Lei

    2013-07-01

    The present experiment evaluated the effects of naltrexone, a non-selective opioid receptor antagonist, on post-abstinence alcohol drinking in C57BL/6NCRL and DBA/2J male mice. Home cage 2-bottle (alcohol vs. water) free-choice procedures were employed. During the pre-abstinence period, alcohol intake was much lower for the DBA/2J mice relative to the C57BL/6NCRL mice, and this strain difference was observed for groups receiving either 3% or 10% alcohol concentrations. The four-day abstinence period effectively reduced alcohol intakes (i.e., a negative alcohol deprivation effect, negative ADE) in both groups of DBA/2J mice, but had no effect on alcohol intakes in either group of C57BL/6NCRL mice. Both groups trained with 3% alcohol received the second four-day abstinence period, where the effects of acute administration of either naltrexone or saline on post-abstinence alcohol drinking were assessed. Naltrexone was more effective in reducing post-abstinence drinking of 3% alcohol in the DBA/2J mice than in the C57BL/6NCRL mice. In the DBA/2J mice, naltrexone further reduced, relative to saline-injected controls, the low levels of post-abstinence alcohol intake. Thus, the low baseline levels of alcohol drinking in DBA/2J mice were further diminished by the four-day abstinence period (negative ADE), and this suppressed post-abstinence level of alcohol drinking was still further reduced by acute administration of naltrexone. The results indicate that naltrexone is effective in reducing further the low levels of alcohol drinking induced by the negative ADE. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Gold nanoshells-mediated bimodal photodynamic and photothermal cancer treatment using ultra-low doses of near infra-red light.

    PubMed

    Vankayala, Raviraj; Lin, Chun-Chih; Kalluru, Poliraju; Chiang, Chi-Shiun; Hwang, Kuo Chu

    2014-07-01

    Previously, gold nanoshells were shown to be able to effectively convert photon energy to heat, leading to hyperthermia and suppression of tumor growths in mice. Herein, we show that in addition to the nanomaterial-mediated photothermal effects (NmPTT), gold nanoshells (including, nanocages, nanorod-in-shell and nanoparticle-in-shell) not only are able to absorb NIR light, but can also emit fluorescence, sensitize formation of singlet oxygen and exert nanomaterial-mediated photodynamic therapeutic (NmPDT) complete destruction of solid tumors in mice. The modes of NmPDT and NmPTT can be controlled and switched from one to the other by changing the excitation wavelength. In the in vitro experiments, gold nanocages and nanorod-in-shell show larger percentage of cellular deaths originating from NmPDT along with the minor fraction of NmPTT effects. In contrast, nanoparticle-in-shell exhibits larger fraction of NmPTT-induced cellular deaths together with minor fraction of NmPDT-induced apoptosis. Fluorescence emission spectra and DPBF quenching studies confirm the generation of singlet O2 upon NIR photoirradiation. Both NmPDT and NmPTT effects were confirmed by measurements of reactive oxygen species (ROS) and subsequent sodium azide quenching, heat shock protein expression (HSP 70), singlet oxygen sensor green (SOSG) sensing, changes in mitochondria membrane potential and apoptosis in the cellular experiments. In vivo experiments further demonstrate that upon irradiation at 980 nm under ultra-low doses (∼150 mW/cm(2)), gold nanocages mostly exert NmPDT effect to effectively suppress the B16F0 melanoma tumor growth. The combination of NmPDT and NmPTT effects on destruction of solid tumors is far better than pure NmPTT effect by 808 nm irradiation and also doxorubicin. Overall, our study demonstrates that gold nanoshells can serve as excellent multi-functional theranostic agents (fluorescence imaging + NmPDT + NmPTT) upon single photon NIR light excitation under

  6. Correlation of ultra-low dose chest CT findings with physiologic measures of asbestosis.

    PubMed

    Manners, David; Wong, Patrick; Murray, Conor; Teh, Joelin; Kwok, Yi Jin; de Klerk, Nick; Alfonso, Helman; Franklin, Peter; Reid, Alison; Musk, A W Bill; Brims, Fraser J H

    2017-08-01

    The correlation between ultra low dose computed tomography (ULDCT)-detected parenchymal lung changes and pulmonary function abnormalities is not well described. This study aimed to determine the relationship between ULDCT-detected interstitial lung disease (ILD) and measures of pulmonary function in an asbestos-exposed population. Two thoracic radiologists independently categorised prone ULDCT scans from 143 participants for ILD appearances as absent (score 0), probable (1) or definite (2) without knowledge of asbestos exposure or lung function. Pulmonary function measures included spirometry and diffusing capacity to carbon monoxide (DLCO). Participants were 92% male with a median age of 73.0 years. CT dose index volume was between 0.6 and 1.8 mGy. Probable or definite ILD was reported in 63 (44.1%) participants. Inter-observer agreement was good (k = 0.613, p < 0.001). There was a statistically significant correlation between the ILD score and both forced expiratory volume in 1 second (FEV 1 ) and forced vital capacity (FVC) (r = -0.17, p = 0.04 and r = -0.20, p = 0.02). There was a strong correlation between ILD score and DLCO (r = -0.34, p < 0.0001). Changes consistent with ILD on ULDCT correlate well with corresponding reductions in gas transfer, similar to standard CT. In asbestos-exposed populations, ULDCT may be adequate to detect radiological changes consistent with asbestosis. • Interobserver agreement for the ILD score using prone ULDCT is good. • Prone ULDCT appearances of ILD correlate with changes in spirometric observations. • Prone ULDCT appearances of ILD correlate strongly with changes in gas transfer. • Prone ULDCT may provide sufficient radiological evidence to inform the diagnosis of asbestosis.

  7. Trial of Naltrexone and Dextromethorphan for Gulf War Veterans’ Illness

    DTIC Science & Technology

    2013-07-01

    AD_________________ Award Number: W81XWH-09-2-0065 TITLE: Trial of Naltrexone and Dextromethorphan ...AND SUBTITLE 5a. CONTRACT NUMBER Trial of Naltrexone and Dextromethorphan for Gulf War Veterans’ Illness 5b. GRANT NUMBER W81XWH-09-2-0065 5c...Sciences has demonstrated that Morphine-related analogs, including Naltrexone and Dextromethorphan , have great potency in anti-inflammation and

  8. Trial of Naltrexone and Dextromethorphan for Gulf War Veterans Illnesses

    DTIC Science & Technology

    2011-07-01

    W81XWH-09-2-0065 TITLE: Trial of Naltrexone and Dextromethorphan for Gulf War Veterans Illnesses PRINCIPAL INVESTIGATOR: William J. Meggs, MD...2011 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Trial of Naltrexone and Dextromethorphan for Gulf War Veterans’ Illness 5b. GRANT NUMBER W81XWH-09...that many with Gulf War Illness could enter either the naltrexone or dextromethorphan arm but not both. We are applying to allow subjects to enter

  9. Magnetic Resonance Relaxometry at Low and Ultra low Fields.

    PubMed

    Volegov, P; Flynn, M; Kraus, R; Magnelind, P; Matlashov, A; Nath, P; Owens, T; Sandin, H; Savukov, I; Schultz, L; Urbaitis, A; Zotev, V; Espy, M

    2010-01-01

    Nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) are ubiquitous tools in science and medicine. NMR provides powerful probes of local and macromolecular chemical structure and dynamics. Recently it has become possible and practical to perform MR at very low fields (from 1 μT to 1 mT), the so-called ultra-low field (ULF) regime. Pulsed pre-polarizing fields greatly enhance the signal strength and allow flexibility in signal acquisition sequences. Improvements in SQUID sensor technology allow ultra-sensitive detection in a pulsed field environment.In this regime the proton Larmor frequencies (1 Hz - 100 kHz) of ULF MR overlap (on a time scale of 10 μs to 100 ms) with "slow" molecular dynamic processes such as diffusion, intra-molecular motion, chemical reactions, and biological processes such as protein folding, catalysis and ligand binding. The frequency dependence of relaxation at ultra-low fields may provide a probe for biomolecular dynamics on the millisecond timescale (protein folding and aggregation, conformational motions of enzymes, binding and structural fluctuations of coupled domains in allosteric mechanisms) relevant to host-pathogen interactions, biofuels, and biomediation. Also this resonance-enhanced coupling at ULF can greatly enhance contrast in medical applications of ULF-MRI resulting in better diagnostic techniques.We have developed a number of instruments and techniques to study relaxation vs. frequency at the ULF regime. Details of the techniques and results are presented.Ultra-low field methods are already being applied at LANL in brain imaging, and detection of liquid explosives at airports. However, the potential power of ultra-low field MR remains to be fully exploited.

  10. Naltrexone for treatment of impaired awareness of hypoglycemia in type 1 diabetes: A randomized clinical trial

    PubMed Central

    Moheet, Amir; Mangia, Silvia; Kumar, Anjali; Tesfaye, Nolawit; Eberly, Lynn E; Bai, Yun; Kubisiak, Kristine; Seaquist, Elizabeth R

    2016-01-01

    Aims Impaired awareness of hypoglycemia (IAH) is a limiting factor in the treatment of type 1 diabetes (T1D) and is a challenging condition to reverse. The objective of this study was to test the hypothesis that naltrexone therapy in subjects with T1D and IAH will improve counterregulatory hormone response and recognition of hypoglycemia symptoms during hypoglycemia. Methods We performed a pilot randomized double blind trial of 4 weeks of naltrexone therapy (n=10) or placebo (n=12) given orally in subjects with T1D and IAH. Outcome measures included hypoglycemia symptom scores, counterregulatory hormone levels and thalamic activation as measured by cerebral blood flow using MRI during experimental hypoglycemia in all subjects before and after 4 weeks of intervention. Results After 4 weeks of therapy with naltrexone or placebo, no significant differences in response to hypoglycemia were seen in any outcomes of interest within each group. Conclusions In this small study, short-term treatment with naltrexone did not improve recognition of hypoglycemia symptoms or counterregulatory hormone response during experimental hypoglycemia in subjects with T1D and IAH. Whether this lack of effect is related to the small sample size or due to the dose, the advanced stage of study population or the drug itself should be the subject of future investigation. PMID:26345338

  11. Employment-based reinforcement of adherence to oral naltrexone treatment in unemployed injection drug users.

    PubMed

    Dunn, Kelly E; Defulio, Anthony; Everly, Jeffrey J; Donlin, Wendy D; Aklin, Will M; Nuzzo, Paul A; Leoutsakos, Jeannie-Marie S; Umbricht, Annie; Fingerhood, Michael; Bigelow, George E; Silverman, Kenneth

    2013-02-01

    Oral naltrexone has high potential for use as a relapse prevention pharmacotherapy for opiate dependence yet suffers from notoriously poor adherence. This study evaluated whether entry to a therapeutic workplace could reinforce adherence with oral naltrexone. Opiate-dependent and cocaine-using injection drug users were detoxified, inducted onto oral naltrexone, and randomly assigned to a contingency (n = 35) or prescription (n = 32) group for a 26-week period. Contingency participants were required to ingest naltrexone under staff observation to gain access to the therapeutic workplace. Prescription participants received a take-home supply of naltrexone and could access the workplace independent of naltrexone ingestion. Primary outcome measures were percent of urine samples positive for naltrexone at 30-day assessments and negative for opiates and cocaine at 30-day assessments. Contingency participants provided significantly more urine samples that were positive for naltrexone compared with prescription participants (72% vs. 21%, p < .01); however, no effect of experimental group was observed on percent opiate-negative (71% vs. 60%, p = .19.) or cocaine-negative (56% vs. 53%, p = .82) samples in the contingency and prescription groups, respectively. Opiate-positive samples were significantly more likely to occur in conjunction with cocaine (p < .001) and when not protected by naltrexone (p < .02), independent of experimental group. Overall, these results show that contingent access to a therapeutic workplace significantly promoted adherence to oral naltrexone, and that the majority of opiate use occurred in conjunction with cocaine use, suggesting that untreated cocaine use may limit the effectiveness of oral naltrexone in promoting opiate abstinence. (c) 2013 APA, all rights reserved.

  12. Trial of Naltrexone and Dextromethorphan for Gulf War Veterans’ Illness

    DTIC Science & Technology

    2012-07-01

    AD_________________ Award Number: W81XWH-09-2-0065 TITLE: Trial of Naltrexone and Dextromethorphan ...TITLE AND SUBTITLE 5a. CONTRACT NUMBER Trial of Naltrexone and Dextromethorphan for Gulf War Veterans’ Illness 5b. GRANT NUMBER W81XWH-09-2-0065...ABSTRACT Approval to separate the study into a separate dextromethorphan arm and naltrexone arm from the Department of Defense Institutional Review

  13. Trial of Naltrexone and Dextromethorphan for Gulf War Veterans’ Illness

    DTIC Science & Technology

    2010-07-01

    09-2-0065 TITLE: Trial of Naltrexone and Dextromethorphan for Gulf War Veterans’ Illness PRINCIPAL INVESTIGATOR: William Joel Meggs, MD, PhD...From - To) 1 JUL 2009 - 30 JUN 2010 4. TITLE AND SUBTITLE Trial of Naltrexone and Dextromethorphan for Gulf War Veteravns’ Illness 5a... dextromethorphan & naltrexone for gulf war illness. 15. SUBJECT TERMS Dextromethorphan , naltexone, gulf war illness 16. SECURITY CLASSIFICATION OF

  14. Naltrexone implant treatment for buprenorphine dependence--Mauritian case series.

    PubMed

    Jhugroo, Anil; Ellayah, Darmen; Norman, Amanda; Hulse, Gary

    2014-08-01

    Although substitution therapy with opiate agonist treatments such as methadone and buprenorphine has resulted in a reduction of illicit drug use related harm, such treatment has also resulted in severe problems in some countries where opioid-dependent individuals now inject illicitly sold buprenorphine or buprenorphine-naloxone instead of heroin. There is no approved treatment for buprenorphine dependence. Naltrexone is an opioid antagonist which has been used for the treatment of both alcohol and opioid dependencies. Although both buprenorphine and heroin resemble each other concerning their effects, buprenorphine has a higher affinity to opioid receptors than heroin. Therefore, it is not known if naltrexone can block the psychoactive effects of buprenorphine as it does for heroin. This paper presents observational case series data on the use of a sustained-release naltrexone implant for the treatment of buprenorphine dependence. To the authors' knowledge this is the first use of sustained-release naltrexone for this indication. © The Author(s) 2014.

  15. [Regulation of the neuronal functional state by ultra low doses of different biologically active substances. Nonspecific effect ].

    PubMed

    Terekhova, S F; Grechenko, T N

    2003-01-01

    The role of biologically active substances in ultra-low doses (10(-15)-10(-27) mol/l) is discussed from the different points of view. The most detailed analysis of neurobiological effects produced by these doses can be studied on the preparate of completely isolated molluscan neurones. In this case the possibility arises to control the first modifications of action at the electrophysiological characteristics of neuronal activity. These changes of electrical activity can be regarded as a reaction to biologically active substance. The following characteristics were controlled: the level of membrane resting potential (MP), the electroexcitable membrane and pacemaker mechanism, chemical sensitivity of somatic membrane loci to neurotransmitter acetylcholine (Ach). Several substances were used in these experiments: two kinds of synthetic antioxidant, GABA, ethanol, serotonine, DSIP (delta-sleep inducing peptide), antibiotic ruboxil, nootrop GVS-111. The isolated neurones were placed into the special chamber. All these substances (0.35 ml) were added single dosing into this chamber with living physiological solution in concentration 10(-15)-10(-27) mol/l. The results demonstrated that all substances had initiated the development of prolonged neurophysiological responses. The intensities of neuronal reactions didn't depend in contact period on the concentration and on the type of substance. It is suggested that these data reveal the existence of unknown modes of regulation of neuronal functional states and presence of hidden channel for information transfer and receiving. This different way of regulation is extremely important influence living organisms.

  16. Employment-Based Reinforcement of Adherence to Oral Naltrexone Treatment in Unemployed Injection Drug Users

    PubMed Central

    Dunn, Kelly; Defulio, Anthony; Everly, Jeffrey J.; Donlin, Wendy D.; Aklin, Will M.; Nuzzo, Paul A.; Leoutsakos, Jeannie-Marie S.; Umbricht, Annie; Fingerhood, Michael; Bigelow, George E.; Silverman, Kenneth

    2013-01-01

    Naltrexone has high potential for use as a relapse prevention pharmacotherapy for opiate dependence; however suffers from notoriously poor adherence when prescribed for oral self-administration. This study evaluated whether entry to a therapeutic workplace could be used to reinforce adherence with oral naltrexone. Opiate-dependent and cocaine-using injection drug users were detoxified, inducted onto oral naltrexone, and randomly assigned to a Contingency (n=35) or Prescription (n=32) group for a 26-week period. Contingency participants were required to ingest naltrexone under staff observation to gain access to the therapeutic workplace. Prescription participants received a take-home supply of naltrexone and could access the workplace independent of naltrexone ingestion. Primary outcome measures were percent of urine samples positive for naltrexone at 30-day assessments and negative for opiates and cocaine at 30-day assessments. Contingency participants provided significantly more urine samples that were positive for naltrexone compared to Prescription participants (72% vs. 21%, P<.01), however no effect of experimental group was observed on percent opiate-negative (71% vs. 60%, P=.19.) or cocaine-negative (56% vs. 53%, P=.82) samples in the Contingency and Prescription groups, respectively. Opiate-positive samples were significantly more likely to occur in conjunction with cocaine (P<.001), and when not protected by naltrexone (P<.02), independent of experimental group. Overall, these results show that contingent access to a therapeutic workplace significantly promoted adherence to oral naltrexone, and that the majority of opiate use occurred in conjunction with cocaine use, suggesting that untreated cocaine use may limit the effectiveness of oral naltrexone in promoting opiate abstinence. PMID:23205722

  17. Naltrexone versus acamprosate in the treatment of alcohol dependence: A multi-centre, randomized, double-blind, placebo-controlled trial.

    PubMed

    Morley, Kirsten C; Teesson, Maree; Reid, Sophie C; Sannibale, Claudia; Thomson, Clare; Phung, Nghi; Weltman, Martin; Bell, James R; Richardson, Kylie; Haber, Paul S

    2006-10-01

    To compare the efficacy of acamprosate and naltrexone in the treatment of alcohol dependence. A double-blind, placebo-controlled trial. Three treatment centres in Australia. A total of 169 alcohol dependent subjects were given naltrexone (50 mg/day), acamprosate (1998 mg/day) or placebo for 12 weeks. All subjects were offered manualized compliance therapy, a brief intervention that targets problems that may affect treatment compliance such as ambivalence and misperceptions about medication. Time to the first drink, time to first relapse, drinks per drinking day and cumulative abstinence. In intention-to-treat analyses, there were no differences between groups on outcome measures of drinking, craving or biochemical markers. Similarly, analyses of the 94 subjects that completed the study in full and demonstrated 80% compliance, revealed no significant treatment effects. Differential treatment effects were identified after stratification according to scores on the Alcohol Dependence Scale (ADS) and Depression Anxiety and Stress Scale (DASS). A significant beneficial treatment effect on time to first relapse was revealed for subjects with 'no depression' allocated to naltrexone (n = 56; P < 0.01). In addition, a significant beneficial treatment effect was revealed in subjects with 'low dependence' allocated to naltrexone (n = 34; P < 0.05). The results of this study support the efficacy of naltrexone in the relapse prevention of alcoholism amongst those with low levels of clinical depression and alcohol dependence severity. No effect of acamprosate was found in our sample.

  18. Role of Bupropion Plus Naltrexone for the Management of Obesity

    PubMed Central

    Booth, Kemper; Clements, Jennifer N.

    2016-01-01

    Objective. The pharmacology, pharmacokinetics, efficacy, and safety of bupropion plus naltrexone for weight loss were reviewed. Data Sources. A MEDLINE search (1970 to November 2015) was conducted for English-language articles using specific MESH terms. Study Selection and Data Extraction. Published Phase 3 clinical trials with primary endpoints related to weight loss were included and critiqued in this review. Study Selection and Data Extraction. Five trials were retrieved and reviewed regarding the efficacy and safety of bupropion plus naltrexone among obese and overweight patients. Data Synthesis. Bupropion is a dopamine/norepinephrine reuptake inhibitor, and naltrexone is an opioid receptor antagonist. The combination of these agents has led to increased weight loss, compared to placebo, among overweight and obese patients with a body mass index (BMI) at or above 30 or BMI at or above 27 with a comorbid condition. The combination of bupropion and naltrexone can produce an average placebo-subtracted weight loss of 4.25% over 56 weeks. Gastrointestinal (ie, nausea, vomiting, constipation) and central nervous system adverse events (ie, headache, dizziness) were commonly reported, and there was a high dropout rate among participants. Conclusions. Bupropion plus naltrexone has demonstrated effective weight loss, in conjunction with lifestyle modifications, among overweight and obese patients with and without comorbidities. Bupropion plus naltrexone has not been studied among special patient populations, such as those with sleep apnea, osteoarthritis, or extreme BMIs. Additional clinical trials and postmarketing data will provide a better understanding of this medication for weight loss.

  19. Trial of Naltrexone and Dextromethorphan for Gulf War Veterans’ Illnesses

    DTIC Science & Technology

    2014-07-01

    09-2-0065 TITLE: Trial of Naltrexone and Dextromethorphan for Gulf War Veterans Illnesses PRINCIPAL INVESTIGATOR: William J. Meggs, MD, PhD... Dextromethorphan and Naltrexone for Gulf War Veterens’ Illness 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-09-2-0065 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR...neuron-inflammation, which can be down regulated, by Naltrexone and Dextromethorphan . This is untested but potentially ground breaking concept that

  20. Naltrexone versus acamprosate: one year follow-up of alcohol dependence treatment.

    PubMed

    Rubio, G; Jiménez-Arriero, M A; Ponce, G; Palomo, T

    2001-01-01

    Naltrexone and acamprosate reduce relapse in alcohol dependence. They have not yet been compared in a published trial. The aim of this study was to compare the efficacy of these compounds in conditions similar to those in routine clinical practice. Random allocation to a year of treatment with naltrexone (50 mg/day) or acamprosate (1665-1998 mg/day) was made in 157 recently detoxified alcohol-dependent men with moderate dependence (evaluated using the Addictions Severity Index and Severity of Alcohol Dependence Scale). All were patients whom a member of the family would accompany regularly to appointments. Alcohol consumption, craving and adverse events were recorded weekly for the first 3 months, and then bi-weekly, by the treating psychiatrist who was not blinded. At 3-monthly intervals, investigators who were blinded to the treatment documented patients' alcohol consumption based on patients' accounts, information given by the psychiatrists when necessary, and reports from patients' families. Serum gamma-glutamyltransferase (GGT) was also measured. Efforts were made to sustain the blindness of the investigators. The same investigator did not assess the same patient twice. The integrity of the blindness was not checked. There was no difference between treatments in mean time to first drink (naltrexone 44 days, acamprosate 39 days) but the time to first relapse (five or more drinks in a day) was 63 days (naltrexone) versus 42 days (acamprosate) (P = 0.02). At the end of 1 year, 41% receiving naltrexone and 17% receiving acamprosate had not relapsed (P = 0.0009). The cumulative number of days of abstinence was significantly greater, and the number of drinks consumed at one time and severity of craving were significantly less, in the naltrexone group compared to the acamprosate group, as was the percentage of heavy drinking days (P = 0.038). More patients in the acamprosate than the naltrexone group were commenced on disulfiram during the study. Naltrexone patients

  1. Naltrexone for the treatment of alcoholism: clinical findings, mechanisms of action, and pharmacogenetics.

    PubMed

    Ray, Lara A; Chin, Pauline F; Miotto, Karen

    2010-03-01

    Naltrexone is an opioid receptor antagonist with established efficacy, albeit moderate, for the treatment of alcohol dependence. This manuscript provides a critical review of the literature on naltrexone as a pharmacotherapy for alcoholism by covering the following areas: (a) clinical findings from treatment studies; (b) pharmacokinetics and safety data; (c) medication compliance and persistence; and (d) neurobiological and biobehavioral mechanisms of action of naltrexone for the indication of alcohol dependence. This review will then focus on the emerging literature on naltrexone pharmacogenetics, which has the potential to identify responders on the basis of genetic variation and to use genetic tools to individualize the use of this medication. Limitations and future directions in the research and practice of naltrexone for alcoholism are also outlined.

  2. Efficacy of Naltrexone for the Treatment of Alcohol Dependence in Latino Populations.

    PubMed

    López, Cristina M; Barr, Simone C; Reid-Quiñones, Kathryn; de Arellano, Michael A

    2017-05-01

    Naltrexone has been identified as a promising psychopharmacological treatment for alcohol dependence. Previous studies have suggested that its efficacy may vary based on ethnic background. The current study examined the efficacy of naltrexone in the treatment of alcohol dependence in Latino adults, a previously unexplored population. This was a secondary analysis of the Combined Pharmacotherapies and Behavioral Interventions for Alcohol Dependence (COMBINE) Study. The overall COMBINE sample consisted of 1,383 adult participants who met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria for alcohol dependence, including 155 Latinos, who are the focus of this report. Consistent with the main trial, primary drinking outcomes, including percentage of days abstinent (PDA) and time to first heavy drinking day (TTHD), were examined. In addition, we examined the effects of naltrexone on a clinically relevant secondary outcome measure, global clinical outcome of alcohol consumption and alcohol-related problems. As seen with the subsample of African Americans from the COMBINE Study, results of the present analysis indicated that there were no significant effects of naltrexone on PDA and TTHD despite these significant effects in the original study. However, contrary to findings in the African American subsample, for Latino participants naltrexone was a significant predictor of a good global clinical outcome (i.e., abstinence or moderate drinking without problems). Naltrexone was not significantly associated with improvements in the primary drinking outcomes of PDA or TTHD at the end of treatment or at follow-up. However, Latinos appeared to benefit from naltrexone as demonstrated by improved ratings of global clinical outcome. These results indicate mixed findings for the efficacy of naltrexone among Latinos in the COMBINE Study.

  3. Improving clinical outcomes for naltrexone as a management of problem alcohol use

    PubMed Central

    Hulse, Gary K

    2013-01-01

    Despite being a relatively effective and safe treatment, the clinical management of alcohol abuse/dependence by oral naltrexone can be compromised due to the patient's non-compliance with daily use of this medication. Over the past decade an increasing body of research has suggested that the use of sustained release depot naltrexone preparations can overcome this issue and deliver improved clinical outcomes. However, at the same time, research findings from diverse areas of pharmacogenetics, neurobiology and behavioural psychology have also been converging to identify variables including genetic markers, patient psychosocial characteristics and drug use history differences, or clusters of these variables that play a major role in mediating the response of alcohol abuse/dependent persons to treatment by naltrexone. While this article does not attempt to review all available data pertaining to an individual alcohol dependent patient's response to treatment by naltrexone, it does identify relevant research areas and highlights the importance of data arising from them. The characterization of clinical markers, to identify those patients who are most likely to benefit from naltrexone and to tailor a more individual naltrexone treatment, will ultimately provide significant benefit to both patients and clinicians by optimizing treatment outcome. PMID:22946873

  4. Randomized Trial of Long-Acting Sustained-Release Naltrexone Implant vs Oral Naltrexone or Placebo for Preventing Relapse to Opioid Dependence

    PubMed Central

    Krupitsky, Evgeny; Zvartau, Edwin; Blokhina, Elena; Verbitskaya, Elena; Wahlgren, Valentina; Tsoy-Podosenin, Marina; Bushara, Natalia; Burakov, Andrey; Masalov, Dmitry; Romanova, Tatyana; Tyurina, Arina; Palatkin, Vladimir; Slavina, Tatyana; Pecoraro, Anna; Woody, George E.

    2013-01-01

    Context Sustained-release naltrexone implants may improve outcomes of nonagonist treatment of opioid addiction. Objective To compare outcomes of naltrexone implants, oral naltrexone hydrochloride, and nonmedication treatment. Design Six-month double-blind, double-dummy, randomized trial. Setting Addiction treatment programs in St Petersburg, Russia. Participants Three hundred six opioid-addicted patients recently undergoing detoxification. Interventions Biweekly counseling and 1 of the following 3 treatments for 24 weeks: (1) 1000-mg naltrexone implant and oral placebo (NI+OP group; 102 patients); (2) placebo implant and 50-mg oral naltrexone hydrochloride (PI+ON group; 102 patients); or (3) placebo implant and oral placebo (PI+OP group; 102 patients). Main Outcome Measure Percentage of patients retained in treatment without relapse. Results By month 6, 54 of 102 patients in the NI+OP group (52.9%) remained in treatment without relapse compared with 16 of 102 patients in the PI+ON group (15.7%) (survival analysis, log-rank test, P<.001) and 11 of 102 patients in the PI+OP group (10.8%) (P<.001). The PI+ON vs PI+OP comparison showed a nonsignificant trend favoring the PI+ON group (P=.07). Counting missing test results as positive, the proportion of urine screening tests yielding negative results for opiates was 63.6% (95% CI, 60%-66%) for the NI+OP group; 42.7% (40%-45%) for the PI+ON group; and 34.1% (32%-37%) for the PI+OP group (P<.001, Fisher exact test, compared with the NI+OP group). Twelve wound infections occurred among 244 implantations (4.9%) in the NI+OP group, 2 among 181 (1.1%) in the PI+ON group, and 1 among 148 (0.7%) in the PI+OP group (P=.02). All events were in the first 2 weeks after implantation and resolved with antibiotic therapy. Four local-site reactions (redness and swelling) occurred in the second month after implantation in the NI+OP group (P=.12), and all resolved with antiallergy medication treatment. Other nonlocal-site adverse effects

  5. Rapid biosynthesis of silver nanoparticles using Crotalaria verrucosa leaves against the dengue vector Aedes aegypti: what happens around? An analysis of dragonfly predatory behaviour after exposure at ultra-low doses.

    PubMed

    Murugan, Kadarkarai; Sanoopa, C P; Madhiyazhagan, Pari; Dinesh, Devakumar; Subramaniam, Jayapal; Panneerselvam, Chellasamy; Roni, Mathath; Suresh, Udaiyan; Nicoletti, Marcello; Alarfaj, Abdullah A; Munusamy, Murugan A; Higuchi, Akon; Kumar, Suresh; Perumalsamy, Haribalan; Ahn, Young-Joon; Benelli, Giovanni

    2016-01-01

    Aedes aegypti is a primary vector of dengue, a mosquito-borne viral disease infecting 50-100 million people every year. Here, we biosynthesised mosquitocidal silver nanoparticles (AgNP) using the aqueous leaf extract of Crotalaria verrucosa. The green synthesis of AgNP was studied by UV-vis spectroscopy, SEM, EDX and FTIR. C. verrucosa-synthesised AgNPs were toxic against A. aegypti larvae and pupae. LC50 of AgNP ranged from 3.496 ppm (I instar larvae) to 17.700 ppm (pupae). Furthermore, we evaluated the predatory efficiency of dragonfly nymphs, Brachydiplax sobrina, against II and III instar larvae of A. aegypti in an aquatic environment contaminated with ultra-low doses of AgNP. Under standard laboratory conditions, predation after 24 h was 87.5% (II) and 54.7% (III). In an AgNP-contaminated environment, predation was 91 and 75.5%, respectively. Overall, C. verrucosa-synthesised AgNP could be employed at ultra-low doses to reduce larval population of dengue vectors enhancing predation rates of dragonfly nymphs.

  6. Multiomics reveal non-alcoholic fatty liver disease in rats following chronic exposure to an ultra-low dose of Roundup herbicide

    PubMed Central

    Mesnage, Robin; Renney, George; Séralini, Gilles-Eric; Ward, Malcolm; Antoniou, Michael N.

    2017-01-01

    The impairment of liver function by low environmentally relevant doses of glyphosate-based herbicides (GBH) is still a debatable and unresolved matter. Previously we have shown that rats administered for 2 years with 0.1 ppb (50 ng/L glyphosate equivalent dilution; 4 ng/kg body weight/day daily intake) of a Roundup GBH formulation showed signs of enhanced liver injury as indicated by anatomorphological, blood/urine biochemical changes and transcriptome profiling. Here we present a multiomic study combining metabolome and proteome liver analyses to obtain further insight into the Roundup-induced pathology. Proteins significantly disturbed (214 out of 1906 detected, q < 0.05) were involved in organonitrogen metabolism and fatty acid β-oxidation. Proteome disturbances reflected peroxisomal proliferation, steatosis and necrosis. The metabolome analysis (55 metabolites altered out of 673 detected, p < 0.05) confirmed lipotoxic conditions and oxidative stress by showing an activation of glutathione and ascorbate free radical scavenger systems. Additionally, we found metabolite alterations associated with hallmarks of hepatotoxicity such as γ-glutamyl dipeptides, acylcarnitines, and proline derivatives. Overall, metabolome and proteome disturbances showed a substantial overlap with biomarkers of non-alcoholic fatty liver disease and its progression to steatohepatosis and thus confirm liver functional dysfunction resulting from chronic ultra-low dose GBH exposure. PMID:28067231

  7. Naltrexone and Cognitive Behavioral Therapy for the Treatment of Alcohol Dependence

    PubMed Central

    Baros, AM; Latham, PK; Anton, RF

    2008-01-01

    Background Sex differences in regards to pharmacotherapy for alcoholism is a topic of concern following publications suggesting naltrexone, one of the longest approved treatments of alcoholism, is not as effective in women as in men. This study was conducted by combining two randomized placebo controlled clinical trials utilizing similar methodologies and personnel in which the data was amalgamated to evaluate sex effects in a reasonable sized sample. Methods 211 alcoholics (57 female; 154 male) were randomized to the naltrexone/CBT or placebo/CBT arm of the two clinical trials analyzed. Baseline variables were examined for differences between sex and treatment groups via analysis of variance (ANOVA) for continuous variable or chi-square test for categorical variables. All initial outcome analysis was conducted under an intent-to-treat analysis plan. Effect sizes for naltrexone over placebo were determined by Cohen’s D (d). Results The effect size of naltrexone over placebo for the following outcome variables was similar in men and women (%days abstinent (PDA) d=0.36, %heavy drinking days (PHDD) d=0.36 and total standard drinks (TSD) d=0.36). Only for men were the differences significant secondary to the larger sample size (PDA p=0.03; PHDD p=0.03; TSD p=0.04). There were a few variables (GGT at wk-12 change from baseline to week-12: men d=0.36, p=0.05; women d=0.20, p=0.45 and drinks per drinking day: men d=0.36, p=0.05; women d=0.28, p=0.34) where the naltrexone effect size for men was greater than women. In women, naltrexone tended to increase continuous abstinent days before a first drink (women d-0.46, p=0.09; men d=0.00, p=0.44). Conclusions The effect size of naltrexone over placebo appeared similar in women and men in our hands suggesting the findings of sex differences in naltrexone response might have to do with sample size and/or endpoint drinking variables rather than any inherent pharmacological or biological differences in response. PMID:18336635

  8. Genetic ancestry as an effect modifier of naltrexone in smoking cessation among African Americans: an analysis of a randomized controlled trial

    PubMed Central

    Bress, Adam; Kittles, Rick; Wing, Coady; Hooker, Stanley E; King, Andrea

    2015-01-01

    Objectives To determine if there were differential quit rates between AA and European Americans (EA) with the experimental treatment naltrexone, and examine the role of genetic ancestry on these outcomes among AAs. Methods Data from a previous randomized trial of 315 smokers to naltrexone vs. placebo were reanalyzed using West African (WA) genetic ancestry to define sub-populations. Logistic regression models were used to estimate treatment effects on early and end of treatment quit rates, by race and WA ancestry. Results Among EAs (n=136), naltrexone significantly increased quit rates at four weeks (62% vs. 43%, p=0.03) with directional, but not statistically significant effects at 12 weeks (30% vs. 18%, p=0.12). In contrast, among the AAs (n=95), quit rates did not differ between naltrexone and placebo groups at either interval (four weeks: 43% vs. 32%, p=0.27; 12 weeks: 22% vs. 18%, p=0.60). A median split was conducted in AAs for WA ancestry. Among AAs with low WA ancestry, quit rates were significantly higher with naltrexone compared with placebo (60% vs. 27%, p=0.03). There was no advantage in quit rates with naltrexone for the high WA ancestry group. Conclusions Naltrexone efficacy for smoking cessation varies across AA subjects with different levels of WA ancestry. These results suggest that genetic background may partially explain racial differences in drug response. PMID:25918964

  9. The Long-Term Survival of a Patient With Stage IV Renal Cell Carcinoma Following an Integrative Treatment Approach Including the Intravenous α-Lipoic Acid/Low-Dose Naltrexone Protocol.

    PubMed

    Berkson, Burton M; Calvo Riera, Francisco

    2017-12-01

    In this case report, we describe the treatment of a 64-year-old male patient diagnosed with metastatic renal cell carcinoma (RCC) in June of 2008. In spite of a left nephrectomy and the standard oncological protocols, the patient developed a solitary left lung metastasis that continued to grow. He was informed that given his diagnosis and poor response to conventional therapy, any further treatment would, at best, be palliative. The patient arrived at the Integrative Medical Center of New Mexico in August of 2010. He was in very poor health, weak, and cachectic. An integrative program-developed by one of the authors using intravenous (IV) α-lipoic acid, IV vitamin C, low-dose naltrexone, and hydroxycitrate, and a healthy life style program-was initiated. From August 2010 to August 2015, the patient's RCC with left lung metastasis was followed closely using computed tomography and positron emission tomography/computed tomography imaging. His most recent positron emission tomography scan demonstrated no residual increased glucose uptake in his left lung. After only a few treatments of IV α-lipoic acid and IV vitamin C, his symptoms began to improve, and the patient regained his baseline weight. His energy and outlook improved, and he returned to work. The patient had stable disease with disappearance of the signs and symptoms of stage IV RCC, a full 9 years following diagnosis, with a gentle integrative program, which is essentially free of side effects. As of November 2017 the patient feels well and is working at his full-time job.

  10. Naltrexone modulates dopamine release following chronic, but not acute amphetamine administration: a translational study

    PubMed Central

    Jayaram-Lindström, N; Guterstam, J; Häggkvist, J; Ericson, M; Malmlöf, T; Schilström, B; Halldin, C; Cervenka, S; Saijo, T; Nordström, A-L; Franck, J

    2017-01-01

    The opioid antagonist naltrexone has been shown to attenuate the subjective effects of amphetamine. However, the mechanisms behind this modulatory effect are currently unknown. We hypothesized that naltrexone would diminish the striatal dopamine release induced by amphetamine, which is considered an important mechanism behind many of its stimulant properties. We used positron emission tomography and the dopamine D2-receptor radioligand [11C]raclopride in healthy subjects to study the dopaminergic effects of an amphetamine injection after pretreatment with naltrexone or placebo. In a rat model, we used microdialysis to study the modulatory effects of naltrexone on dopamine levels after acute and chronic amphetamine exposure. In healthy humans, naltrexone attenuated the subjective effects of amphetamine, confirming our previous results. Amphetamine produced a significant reduction in striatal radioligand binding, indicating increased levels of endogenous dopamine. However, there was no statistically significant effect of naltrexone on dopamine release. The same pattern was observed in rats, where an acute injection of amphetamine caused a significant rise in striatal dopamine levels, with no effect of naltrexone pretreatment. However, in a chronic model, naltrexone significantly attenuated the dopamine release caused by reinstatement of amphetamine. Collectively, these data suggest that the opioid system becomes engaged during the more chronic phase of drug use, evidenced by the modulatory effect of naltrexone on dopamine release following chronic amphetamine administration. The importance of opioid-dopamine interactions in the reinforcing and addictive effects of amphetamine is highlighted by the present findings and may help to facilitate medication development in the field of stimulant dependence. PMID:28440810

  11. Employment-based Reinforcement of Adherence to Oral Naltrexone in Unemployed Injection Drug Users: 12-month Outcomes

    PubMed Central

    Dunn, Kelly; DeFulio, Anthony; Everly, Jeffrey J.; Donlin, Wendy D.; Aklin, Will M.; Nuzzo, Paul A.; Leoutsakos, Jeannie-Marie S.; Umbricht, Annie; Fingerhood, Michael; Bigelow, George E.; Silverman, Kenneth

    2015-01-01

    Oral naltrexone could be a promising relapse prevention pharmacotherapy for recently detoxified opioid-dependent patients, however interventions are often needed to promote adherence with this treatment approach. We recently conducted a study to evaluate a 26-week employment-based reinforcement intervention of oral naltrexone in unemployed injection drug users (Dunn et al., 2013). Participants were randomly assigned into a Contingency (n=35) group required to ingest naltrexone under staff observation to gain entry into a therapeutic workplace, or a Prescription (n=32) group given a take-home supply of oral naltrexone and access to the workplace without observed ingestion. Monthly urine samples were collected and analyzed for evidence for naltrexone adherence, opioid use, and cocaine use. As previously reported, Contingency participants provided significantly more naltrexone-positive urine samples than Prescription participants during the 26-week intervention period. The goal of this current study is to report the 12-month outcomes, which occurred 6 months after the intervention ended. Results at the 12-month visit showed no between-group differences in naltrexone-positive, opioid-negative, or cocaine-negative urine samples, and no participant self-reported using naltrexone at the follow-up visit. These results show that even after a period of successfully reinforced oral naltrexone adherence longer-term naltrexone use is unlikely to be maintained after reinforcement contingencies are discontinued. PMID:25134047

  12. Accuracy of computer-aided design models of the jaws produced using ultra-low MDCT doses and ASIR and MBIR.

    PubMed

    Al-Ekrish, Asma'a A; Alfadda, Sara A; Ameen, Wadea; Hörmann, Romed; Puelacher, Wolfgang; Widmann, Gerlig

    2018-06-16

    To compare the surface of computer-aided design (CAD) models of the maxilla produced using ultra-low MDCT doses combined with filtered backprojection (FBP), adaptive statistical iterative reconstruction (ASIR) and model-based iterative reconstruction (MBIR) reconstruction techniques with that produced from a standard dose/FBP protocol. A cadaveric completely edentulous maxilla was imaged using a standard dose protocol (CTDIvol: 29.4 mGy) and FBP, in addition to 5 low dose test protocols (LD1-5) (CTDIvol: 4.19, 2.64, 0.99, 0.53, and 0.29 mGy) reconstructed with FBP, ASIR 50, ASIR 100, and MBIR. A CAD model from each test protocol was superimposed onto the reference model using the 'Best Fit Alignment' function. Differences between the test and reference models were analyzed as maximum and mean deviations, and root-mean-square of the deviations, and color-coded models were obtained which demonstrated the location, magnitude and direction of the deviations. Based upon the magnitude, size, and distribution of areas of deviations, CAD models from the following protocols were comparable to the reference model: FBP/LD1; ASIR 50/LD1 and LD2; ASIR 100/LD1, LD2, and LD3; MBIR/LD1. The following protocols demonstrated deviations mostly between 1-2 mm or under 1 mm but over large areas, and so their effect on surgical guide accuracy is questionable: FBP/LD2; MBIR/LD2, LD3, LD4, and LD5. The following protocols demonstrated large deviations over large areas and therefore were not comparable to the reference model: FBP/LD3, LD4, and LD5; ASIR 50/LD3, LD4, and LD5; ASIR 100/LD4, and LD5. When MDCT is used for CAD models of the jaws, dose reductions of 86% may be possible with FBP, 91% with ASIR 50, and 97% with ASIR 100. Analysis of the stability and accuracy of CAD/CAM surgical guides as directly related to the jaws is needed to confirm the results.

  13. Naltrexone Maintenance Decreases Cannabis Self-Administration and Subjective Effects in Daily Cannabis Smokers.

    PubMed

    Haney, Margaret; Ramesh, Divya; Glass, Andrew; Pavlicova, Martina; Bedi, Gillinder; Cooper, Ziva D

    2015-10-01

    Given that cannabis use is increasing in the United States, pharmacological treatment options to treat cannabis use disorder are needed. Opioid antagonists modulate cannabinoid effects and may offer a potential approach to reducing cannabis use. In this double-blind, placebo-controlled human laboratory study, we assessed the effects of naltrexone maintenance on the reinforcing, subjective, psychomotor, and cardiovascular effects of active and inactive cannabis. Nontreatment-seeking, daily cannabis smokers were randomized to receive naltrexone (50 mg: n=18 M and 5 F) or placebo (0 mg; n=26 M and 2 F) capsules for 16 days. Before, during, and after medication maintenance, participants completed 10 laboratory sessions over 4-6 weeks, assessing cannabis' behavioral and cardiovascular effects. Medication compliance was verified by observed capsule administration, plasma naltrexone, and urinary riboflavin. Relative to placebo, maintenance on naltrexone significantly reduced both active cannabis self-administration and its positive subjective effects ('good effect'). Participants in the placebo group had 7.6 times (95% CI: 1.1-51.8) the odds of self-administering active cannabis compared with the naltrexone group. This attenuation of reinforcing and positive subjective effects also influenced cannabis use in the natural ecology. Naltrexone had intrinsic effects: decreasing ratings of friendliness, food intake, and systolic blood pressure, and increasing spontaneous reports of stomach upset and headache, yet dropout rates were comparable between groups. In summary, we show for the first time that maintenance on naltrexone decreased cannabis self-administration and ratings of 'good effect' in nontreatment-seeking daily cannabis smokers. Clinical studies in patients motivated to reduce their cannabis use are warranted to evaluate naltrexone's efficacy as a treatment for cannabis use disorder.

  14. Optimization of naltrexone diclofenac codrugs for sustained drug delivery across microneedle-treated skin.

    PubMed

    Ghosh, Priyanka; Lee, DoMin; Kim, Kyung Bo; Stinchcomb, Audra L

    2014-01-01

    The purpose of this work was to optimize the structure of codrugs for extended delivery across microneedle treated skin. Naltrexone, the model compound was linked with diclofenac, a nonspecific cyclooxygenase inhibitor to enhance the pore lifetime following microneedle treatment and develop a 7 day transdermal system for naltrexone. Four different codrugs of naltrexone and diclofenac were compared in terms of stability and solubility. Transdermal flux, permeability and skin concentration of both parent drugs and codrugs were quantified to form a structure permeability relationship. The results indicated that all codrugs bioconverted in the skin. The degree of conversion was dependent on the structure, phenol linked codrugs were less stable compared to the secondary alcohol linked structures. The flux of naltrexone across microneedle treated skin and the skin concentration of diclofenac were higher for the phenol linked codrugs. The polyethylene glycol link enhanced solubility of the codrugs, which translated into flux enhancement. The current studies indicated that formulation stability of codrugs and the flux of naltrexone can be enhanced via structure design optimization. The polyethylene glycol linked naltrexone diclofenac codrug is better suited for a 7 day drug delivery system both in terms of stability and drug delivery.

  15. Naltrexone implants compared to methadone: outcomes six months after prison release.

    PubMed

    Lobmaier, Philipp P; Kunøe, Nikolaj; Gossop, Michael; Katevoll, Tormod; Waal, Helge

    2010-01-01

    After prison release, offenders with heroin use problems are at high risk of relapse and overdose death. There is a particular need for treatments that can be initiated in prison and continued after release into the community. Methadone maintenance treatment has been shown to reduce heroin use, criminality and mortality. Naltrexone implant treatment has not previously been evaluated in prison settings. This study compares the effects of naltrexone implants and methadone treatment on heroin and other illicit drug use, and criminality among heroin-dependent inmates after release from prison. Forty-six volunteers were randomly allocated to naltrexone implants or methadone before release. Intention-to-treat analyses showed reductions in both groups in frequency of use of heroin and benzodiazepines, as well as criminality, 6 months after prison release. Naltrexone implants may be a valuable treatment option in prison settings. 2010 S. Karger AG, Basel.

  16. Maintenance on naltrexone+amphetamine decreases cocaine-vs.-food choice in male rhesus monkeys.

    PubMed

    Moerke, Megan J; Banks, Matthew L; Cheng, Kejun; Rice, Kenner C; Negus, S Stevens

    2017-12-01

    Cocaine use disorder remains a significant public health issue for which there are no FDA-approved pharmacotherapies. Amphetamine maintenance reduces cocaine use in preclinical and clinical studies, but the mechanism of this effect is unknown. Previous studies indicate a role for endogenous opioid release and subsequent opioid receptor activation in some amphetamine effects; therefore, the current study examined the role of mu-opioid receptor activation in d-amphetamine treatment effects in an assay of cocaine-vs-food choice. Adult male rhesus monkeys with double-lumen intravenous catheters responded for concurrently available food pellets and cocaine injections (0-0.1mg/kg/injection) during daily sessions. Cocaine choice and overall reinforcement rates were evaluated during 7-day treatments with saline or test drugs. During saline treatment, cocaine maintained a dose-dependent increase in cocaine-vs.-food choice. The mu-opioid receptor agonist morphine (0.032-0.32mg/kg/h) dose-dependently increased cocaine choice and decreased rates of reinforcement. A dose of the mu-selective opioid receptor antagonist naltrexone (0.0032mg/kg/h) that completely blocked morphine effects had no effect on cocaine choice when it was administered alone, but it enhanced the effectiveness of a threshold dose of 0.032mg/kg/h amphetamine to decrease cocaine choice without also enhancing nonselective behavioral disruption by this dose of amphetamine. Conversely, the kappa-selective opioid antagonist norbinalorphimine did not enhance amphetamine effects on cocaine choice. These results suggest that amphetamine maintenance produces mu opioid-receptor mediated effects that oppose its anti-cocaine effects. Co-administration of naltrexone may selectively enhance amphetamine potency to decrease cocaine choice without increasing amphetamine potency to produce general behavioral disruption. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Accelerated in vitro release testing method for naltrexone loaded PLGA microspheres.

    PubMed

    Andhariya, Janki V; Choi, Stephanie; Wang, Yan; Zou, Yuan; Burgess, Diane J; Shen, Jie

    2017-03-30

    The objective of the present study was to develop a discriminatory and reproducible accelerated release testing method for naltrexone loaded parenteral polymeric microspheres. The commercially available naltrexone microsphere product (Vivitrol ® ) was used as the testing formulation in the in vitro release method development, and both sample-and-separate and USP apparatus 4 methods were investigated. Following an in vitro drug stability study, frequent media replacement and addition of anti-oxidant in the release medium were used to prevent degradation of naltrexone during release testing at "real-time" (37°C) and "accelerated" (45°C), respectively. The USP apparatus 4 method was more reproducible than the sample-and-separate method. In addition, the accelerated release profile obtained using USP apparatus 4 had a shortened release duration (within seven days), and good correlation with the "real-time" release profile. Lastly, the discriminatory ability of the developed accelerated release method was assessed using compositionally equivalent naltrexone microspheres with different release characteristics. The developed accelerated USP apparatus 4 release method was able to detect differences in the release characteristics of the prepared naltrexone microspheres. Moreover, a linear correlation was observed between the "real-time" and accelerated release profiles of all the formulations investigated, suggesting that the release mechanism(s) may be similar under both conditions. These results indicate that the developed accelerated USP apparatus 4 method has the potential to be an appropriate fast quality control tool for long-acting naltrexone PLGA microspheres. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Naltrexone treatment reverses astrocyte atrophy and immune dysfunction in self-harming macaques

    PubMed Central

    Lee, Kim M.; Chiu, Kevin B.; Didier, Peter J.; Baker, Kate C.; MacLean, Andrew G.

    2015-01-01

    The role of glia in the development and treatment of behavioral abnormalities is understudied. Recent reports have observed glial activation in several disorders, including depression, autism spectrum disorders and self-injurious behaviors (SIB). In the current study, we examined SIB in the physiologically and anatomically relevant nonhuman primate (NHP) model. At the Tulane National Primate Research Center (TNPRC), approximately 5% of singly housed macaques develop symptoms of SIB. We have previously demonstrated that naltrexone hydrochloride can be effective in reducing SIB. We have also demonstrated that the astrocytes of animals with SIB are distinctly atrophic and display heightened innate immune activation compared with control animals. We have added a third group of animals (five macaques identified with SIB and treated with oral naltrexone at a dose of 3.2 mg/kg) to the previous cohort (six macaques with a history of SIB but not treated, and nine animals with no history of SIB) for this study. Gray and white matter astrocytes from frontal cortical tissue were examined following necropsy. Innate immune activation of astrocytes, which was increased in SIB animals, was markedly decreased in animals receiving naltrexone, as was atrophy of both grey and white matter astrocytes. This was concomitant with improved behavioral correlates. Preventing astrocyte activation in select areas of the brain to reduce injurious behavior is an innovative concept with implications for mental health studies. Differences in multiple areas of primate brain would help determine how self-injurious behavior develops. These studies suggest a stronger role for astrocytes in the cellular events associated with self-injurious behaviors. PMID:26191654

  19. Brain MR imaging at ultra-low radiofrequency power.

    PubMed

    Sarkar, Subhendra N; Alsop, David C; Madhuranthakam, Ananth J; Busse, Reed F; Robson, Philip M; Rofsky, Neil M; Hackney, David B

    2011-05-01

    To explore the lower limits for radiofrequency (RF) power-induced specific absorption rate (SAR) achievable at 1.5 T for brain magnetic resonance (MR) imaging without loss of tissue signal or contrast present in high-SAR clinical imaging in order to create a potentially viable MR method at ultra-low RF power to image tissues containing implanted devices. An institutional review board-approved HIPAA-compliant prospective MR study design was used, with written informed consent from all subjects prior to MR sessions. Seven healthy subjects were imaged prospectively at 1.5 T with ultra-low-SAR optimized three-dimensional (3D) fast spin-echo (FSE) and fluid-attenuated inversion-recovery (FLAIR) T2-weighted sequences and an ultra-low-SAR 3D spoiled gradient-recalled acquisition in the steady state T1-weighted sequence. Corresponding high-SAR two-dimensional (2D) clinical sequences were also performed. In addition to qualitative comparisons, absolute signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) for multicoil, parallel imaging acquisitions were generated by using a Monte Carlo method for quantitative comparison between ultra-low-SAR and high-SAR results. There were minor to moderate differences in the absolute tissue SNR and CNR values and in qualitative appearance of brain images obtained by using ultra-low-SAR and high-SAR techniques. High-SAR 2D T2-weighted imaging produced slightly higher SNR, while ultra-low-SAR 3D technique not only produced higher SNR for T1-weighted and FLAIR images but also higher CNRs for all three sequences for most of the brain tissues. The 3D techniques adopted here led to a decrease in the absorbed RF power by two orders of magnitude at 1.5 T, and still the image quality was preserved within clinically acceptable imaging times. RSNA, 2011

  20. Low-cost ultra-thin broadband terahertz beam-splitter.

    PubMed

    Ung, Benjamin S-Y; Fumeaux, Christophe; Lin, Hungyen; Fischer, Bernd M; Ng, Brian W-H; Abbott, Derek

    2012-02-27

    A low-cost terahertz beam-splitter is fabricated using ultra-thin LDPE plastic sheeting coated with a conducting silver layer. The beam splitting ratio is determined as a function of the thickness of the silver layer--thus any required splitting ratio can be printed on demand with a suitable rapid prototyping technology. The low-cost aspect is a consequence of the fact that ultra-thin LDPE sheeting is readily obtainable, known more commonly as domestic plastic wrap or cling wrap. The proposed beam-splitter has numerous advantages over float zone silicon wafers commonly used within the terahertz frequency range. These advantages include low-cost, ease of handling, ultra-thin thickness, and any required beam splitting ratio can be readily fabricated. Furthermore, as the beam-splitter is ultra-thin, it presents low loss and does not suffer from Fabry-Pérot effects. Measurements performed on manufactured prototypes with different splitting ratios demonstrate a good agreement with our theoretical model in both P and S polarizations, exhibiting nearly frequency-independent splitting ratios in the terahertz frequency range.

  1. Opioid antagonism of cannabinoid effects: differences between marijuana smokers and nonmarijuana smokers.

    PubMed

    Haney, Margaret

    2007-06-01

    In non-human animals, opioid antagonists block the reinforcing and discriminative-stimulus effects of Delta(9)-tetrahydrocannabinol (THC), while in human marijuana smokers, naltrexone (50 mg) enhances the reinforcing and subjective effects of THC. The objective of this study was to test a lower, more opioid-selective dose of naltrexone (12 mg) in combination with THC. The influence of marijuana-use history and sex was also investigated. Naltrexone (0, 12 mg) was administered 30 min before oral THC (0-40 mg) or methadone (0-10 mg) capsules, and subjective effects, task performance, pupillary diameter, and cardiovascular parameters were assessed in marijuana smoking (Study 1; n=22) and in nonmarijuana smoking (Study 2; n=21) men and women. The results show that in marijuana smokers, low-dose naltrexone blunted the intoxicating effects of a low THC dose (20 mg), while increasing ratings of anxiety at a higher THC dose (40 mg). In nonmarijuana smokers, low-dose naltrexone shifted THC's effects in the opposite direction, enhancing the intoxicating effects of a low THC dose (2.5 mg) and decreasing anxiety ratings following a high dose of THC (10 mg). There were no sex differences in these interactions, although among nonmarijuana smokers, men were more sensitive to the effects of THC alone than women. To conclude, a low, opioid-selective dose of naltrexone blunted THC intoxication in marijuana smokers, while in nonmarijuana smokers, naltrexone enhanced THC intoxication. These data demonstrate that the interaction between opioid antagonists and cannabinoid agonists varies as a function of marijuana use history.

  2. Naltrexone Maintenance Decreases Cannabis Self-Administration and Subjective Effects in Daily Cannabis Smokers

    PubMed Central

    Haney, Margaret; Ramesh, Divya; Glass, Andrew; Pavlicova, Martina; Bedi, Gillinder; Cooper, Ziva D

    2015-01-01

    Given that cannabis use is increasing in the United States, pharmacological treatment options to treat cannabis use disorder are needed. Opioid antagonists modulate cannabinoid effects and may offer a potential approach to reducing cannabis use. In this double-blind, placebo-controlled human laboratory study, we assessed the effects of naltrexone maintenance on the reinforcing, subjective, psychomotor, and cardiovascular effects of active and inactive cannabis. Nontreatment-seeking, daily cannabis smokers were randomized to receive naltrexone (50 mg: n=18 M and 5 F) or placebo (0 mg; n=26 M and 2 F) capsules for 16 days. Before, during, and after medication maintenance, participants completed 10 laboratory sessions over 4–6 weeks, assessing cannabis' behavioral and cardiovascular effects. Medication compliance was verified by observed capsule administration, plasma naltrexone, and urinary riboflavin. Relative to placebo, maintenance on naltrexone significantly reduced both active cannabis self-administration and its positive subjective effects (‘good effect'). Participants in the placebo group had 7.6 times (95% CI: 1.1–51.8) the odds of self-administering active cannabis compared with the naltrexone group. This attenuation of reinforcing and positive subjective effects also influenced cannabis use in the natural ecology. Naltrexone had intrinsic effects: decreasing ratings of friendliness, food intake, and systolic blood pressure, and increasing spontaneous reports of stomach upset and headache, yet dropout rates were comparable between groups. In summary, we show for the first time that maintenance on naltrexone decreased cannabis self-administration and ratings of ‘good effect' in nontreatment-seeking daily cannabis smokers. Clinical studies in patients motivated to reduce their cannabis use are warranted to evaluate naltrexone's efficacy as a treatment for cannabis use disorder. PMID:25881117

  3. Effect of naltrexone treatment on the treadmill exercise-induced hormone release in amenorrheic women.

    PubMed

    Botticelli, G; Bacchi Modena, A; Bresciani, D; Villa, P; Aguzzoli, L; Florio, P; Nappi, R E; Petraglia, F; Genazzani, A R

    1992-12-01

    The effect of an acute physical stress on hormone secretions before and after a 10-day naltrexone treatment in untrained healthy and amenorrheic women was investigated. Plasma levels of pituitary (LH, FSH, prolactin, GH, ACTH, beta-endorphin) and adrenal (cortisol, androstenedione, testosterone) hormones were measured at rest and in response to 60 min of physical exercise. The test was done both before and after a 10-day naltrexone (50 mg/day) treatment. Graded levels of treadmill exercise (50, 70 and 90% of maximal oxygen uptake (VO2) every 20 min) was used as physical stressor. While mean +/- SE plasma LH levels in control women were higher than in amenorrheic patients and increased following the naltrexone treatment (p < 0.01), no significant differences of basal plasma hormonal levels were observed between amenorrheic and eumenorrheic women, both before and after naltrexone treatment. Physical exercise at 90% VO2 induced a significant increase in plasma GH, ACTH, beta-endorphin, cortisol, androstenedione and testosterone levels in controls before naltrexone treatment (p < 0.01). The mean increase in plasma androstenedione and testosterone levels in control women was significantly higher after naltrexone treatment (p < 0.01). In amenorrheic patients before naltrexone, physical exercise induced an increase in plasma prolactin and GH levels, but not in plasma ACTH, beta-endorphin, cortisol, testosterone and androstenedione. After naltrexone treatment, the exercise induced a significant plasma ACTH, beta-endorphin and cortisol levels, while the increase of plasma prolactin levels was significantly higher than before treatment (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Employment-Based Reinforcement of Adherence to Depot Naltrexone in Unemployed Opioid-Dependent Adults: A Randomized Controlled Trial

    PubMed Central

    Everly, Jeffrey J.; DeFulio, Anthony; Koffarnus, Mikhail N.; Leoutsakos, Jeannie-Marie S.; Donlin, Wendy D.; Aklin, Will M.; Umbricht, Annie; Fingerhood, Michael; Bigelow, George E.; Silverman, Kenneth

    2011-01-01

    Aims Naltrexone can be used to treat opioid dependence, but patients refuse to take it. Extended-release depot formulations may improve adherence, but long-term adherence rates to depot naltrexone are not known. This study determined long-term rates of adherence to depot naltrexone and whether employment-based reinforcement can improve adherence. Design Participants who were inducted onto oral naltrexone were randomly assigned to Contingency (n=18) or Prescription (n=17) groups. Participants were offered six depot naltrexone injections and invited to work at the therapeutic workplace weekdays for 26 weeks where they earned stipends for participating in job skills training. Contingency participants were required to accept naltrexone injections to maintain workplace access and to maintain maximum pay. Prescription participants could work independent of whether they accepted injections. Setting The therapeutic workplace, a model employment-based intervention for drug addiction and unemployment. Participants Opioid-dependent unemployed adults. Measurements Depot naltrexone injections accepted and opiate-negative urine samples. Findings Contingency participants accepted significantly more naltrexone injections than Prescription participants (81% versus 42%), and were more likely to accept all injections (66% versus 35%). At monthly assessments (with missing urine samples imputed as positive), the groups provided similar percentages of samples negative for opiates (74% versus 62%) and for cocaine (56% versus 54%). Opiate positive samples were more likely when samples were also positive for cocaine. Conclusions Employment-based reinforcement can maintain adherence to depot naltrexone. Future research should determine whether persistent cocaine use compromises naltrexone's effect on opiate use. Workplaces may be useful for promoting sustained adherence to depot naltrexone. PMID:21320227

  5. Effect of naltrexone and ondansetron on alcohol cue-induced activation of the ventral striatum in alcohol-dependent people.

    PubMed

    Myrick, Hugh; Anton, Raymond F; Li, Xingbao; Henderson, Scott; Randall, Patrick K; Voronin, Konstantin

    2008-04-01

    Medication for the treatment of alcoholism is currently not particularly robust. Neuroimaging techniques might predict which medications could be useful in the treatment of alcohol dependence. To explore the effect of naltrexone, ondansetron hydrochloride, or the combination of these medications on cue-induced craving and ventral striatum activation. Functional brain imaging was conducted during alcohol cue presentation. Participants were recruited from the general community following media advertisement. Experimental procedures were performed in the magnetic resonance imaging suite of a major training hospital and medical research institute. Ninety non-treatment-seeking alcohol-dependent (by DSM-IV criteria) and 17 social drinking (< 14 drinks per week) paid volunteers recruited through advertisements at an academic center. A taste of alcohol and a series of alcohol-related pictures, neutral beverage pictures, and visual control images were provided to volunteers after 7 days of double-blind randomly assigned daily dosing with 50 mg of naltrexone (n = 23), 0.50 mg of ondansetron hydrochloride (n = 23), the combination of the 2 medications (n = 20), or matching placebos (n = 24). Difference in brain blood oxygen level-dependent magnetic resonance when viewing alcohol pictures vs neutral beverage pictures with a particular focus on ventral striatum activity comparison across medication groups. Self-ratings of alcohol craving. The combination treatment decreased craving for alcohol. Naltrexone with (P = .02) or without (P = .049) ondansetron decreased alcohol cue-induced activation of the ventral striatum. Ondansetron by itself was similar to naltrexone and the combination in the overall analysis but intermediate in a region-specific analysis. Consistent with animal data that suggest that both naltrexone and ondansetron reduce alcohol-stimulated dopamine output in the ventral striatum, the current study found evidence that these medications, alone or in combination

  6. Long-acting injectable versus oral naltrexone maintenance therapy with psychosocial intervention for heroin dependence: a quasi-experiment.

    PubMed

    Brooks, Adam C; Comer, Sandra D; Sullivan, Maria A; Bisaga, Adam; Carpenter, Kenneth M; Raby, Wilfrid M; Yu, Elmer; O'Brien, Charles P; Nunes, Edward V

    2010-10-01

    To conduct a quasi-experimental comparison of early clinical outcomes between injectable, sustained-release, depot naltrexone formulation versus oral naltrexone maintenance therapy in individuals with opiate dependence. Early retention in treatment and urine-confirmed opiate use in the first 8 weeks postdetoxification were compared between patients (diagnosed as opiate-dependent according to DSM-IV criteria) participating in 2 concurrently run randomized clinical trials of oral (n = 69; patients treated from September 1999 to May 2002) and long-acting injectable (n = 42; patients treated from November 2000 to June 2003) naltrexone maintenance therapy with psychosocial therapy. Long-acting injectable naltrexone produced significantly better outcome than oral naltrexone on days retained in treatment (F(1,106) = 6.49, P = .012) and for 1 measure of opiate use (F(1,106) = 5.26, P = .024); other measures were not significantly different, but differences were in the same direction. In subanalyses, there were interaction effects between baseline heroin use severity and type of treatment. In subanalyses, heroin users with more severe baseline use showed better retention with oral naltrexone maintenance therapy combined with intensive psychotherapy (behavioral naltrexone therapy) as compared to retention shown by severe heroin users treated with long-acting naltrexone injections combined with standard cognitive-behavioral therapy (χ²(1)= 9.31, P = .002); less severe heroin users evidenced better outcomes when treated with long-acting injectable naltrexone. This quasi-experimental analysis provides tentative indications of superior outcomes for heroin-dependent patients treated with long-acting injectable naltrexone compared to oral naltrexone. The finding that heroin users with more severe baseline use achieved better outcomes with oral naltrexone is most probably attributable to the intensive nature of the psychosocial treatments provided and points to the opportunity

  7. Extreme sensitivity of gene expression in human SH-SY5Y neurocytes to ultra-low doses of Gelsemium sempervirens

    PubMed Central

    2014-01-01

    Background Gelsemium sempervirens L. (Gelsemium s.) is a traditional medicinal plant, employed as an anxiolytic at ultra-low doses and animal models recently confirmed this activity. However the mechanisms by which it might operate on the nervous system are largely unknown. This work investigates the gene expression of a human neurocyte cell line treated with increasing dilutions of Gelsemium s. extract. Methods Starting from the crude extract, six 100 × (centesimal, c) dilutions of Gelsemium s. (2c, 3c, 4c, 5c, 9c and 30c) were prepared according to the French homeopathic pharmacopoeia. Human SH-SY5Y neuroblastoma cells were exposed for 24 h to test dilutions, and their transcriptome compared by microarray to that of cells treated with control vehicle solutions. Results Exposure to the Gelsemium s. 2c dilution (the highest dose employed, corresponding to a gelsemine concentration of 6.5 × 10-9 M) significantly changed the expression of 56 genes, of which 49 were down-regulated and 7 were overexpressed. Several of the down-regulated genes belonged to G-protein coupled receptor signaling pathways, calcium homeostasis, inflammatory response and neuropeptide receptors. Fisher exact test, applied to the group of 49 genes down-regulated by Gelsemium s. 2c, showed that the direction of effects was significantly maintained across the treatment with high homeopathic dilutions, even though the size of the differences was distributed in a small range. Conclusions The study shows that Gelsemium s., a medicinal plant used in traditional remedies and homeopathy, modulates a series of genes involved in neuronal function. A small, but statistically significant, response was detected even to very low doses/high dilutions (up to 30c), indicating that the human neurocyte genome is extremely sensitive to this regulation. PMID:24642002

  8. Employment-based reinforcement of adherence to depot naltrexone in unemployed opioid-dependent adults: a randomized controlled trial.

    PubMed

    Everly, Jeffrey J; DeFulio, Anthony; Koffarnus, Mikhail N; Leoutsakos, Jeannie-Marie S; Donlin, Wendy D; Aklin, Will M; Umbricht, Annie; Fingerhood, Michael; Bigelow, George E; Silverman, Kenneth

    2011-07-01

    Naltrexone can be used to treat opioid dependence, but patients refuse to take it. Extended-release depot formulations may improve adherence, but long-term adherence rates to depot naltrexone are not known. This study determined long-term rates of adherence to depot naltrexone and whether employment-based reinforcement can improve adherence. Participants who were inducted onto oral naltrexone were assigned randomly to contingency (n = 18) or prescription (n = 17) groups. Participants were offered six depot naltrexone injections and invited to work at the therapeutic workplace on week days for 26 weeks, where they earned stipends for participating in job skills training. Contingency participants were required to accept naltrexone injections to maintain workplace access and to maintain maximum pay. Prescription participants could work independently of whether they accepted injections. The therapeutic workplace, a model employment-based intervention for drug addiction and unemployment. Opioid-dependent unemployed adults. Depot naltrexone injections accepted and opiate-negative urine samples. Contingency participants accepted significantly more naltrexone injections than prescription participants (81% versus 42%), and were more likely to accept all injections (66% versus 35%). At monthly assessments (with missing urine samples imputed as positive), the groups provided similar percentages of samples negative for opiates (74% versus 62%) and for cocaine (56% versus 54%). Opiate-positive samples were more likely when samples were also positive for cocaine. Employment-based reinforcement can maintain adherence to depot naltrexone. Future research should determine whether persistent cocaine use compromises naltrexone's effect on opiate use. Workplaces may be useful for promoting sustained adherence to depot naltrexone. © 2011 The Authors, Addiction © 2011 Society for the Study of Addiction.

  9. Combination Treatment of Glioblastoma by Low-Dose Radiation and Genistein.

    PubMed

    Atefeh, Zamanian; Vahid, Changizi; Hasan, Nedaie; Saeed, Amanpour; Mahnaz, Haddadi

    2016-01-01

    Gioblastoma multiforme as a chemoresistant and radioresistant malignant cell line needs to novel strategies to treatment. Low-dose hyper-radiosensitivity (LDHRS) seems to be an effective phenomenon to irradiation that can save normal brain fibroblasts. Genistein which is a soy isoflavone can be cytotoxic in some tumor cell lines. So we determined to study the effect of combining these two treatment modalities. After 30 hours incubation with Genistein in different concentrations on U87MG cell line, proliferation and clonogenicity were conducted by both clonogenic and MTT assays. A conventional 2Gy radiation dose was compared with 10 doses of 0.2Gy gamma irradiation with 3 minutes and 1 hour intervals. Finally, concurrent effect of these modalities was assessed. Based on acquired cell doubling time (30 hours), one doubling time treatment by Genistein could decrease clonogenicity. U87MG cell line exhibited HRS at low dose irradiations. 2Gy irradiation was more effective than ultra-fractionation methods in comparison with control group. All groups with 50uM concentration of Genistein showed decrease in the survival. This decrease compared with control group, in 10x0.2Gy with 3 minutes intervals plus 50uM Genistein was significant and for groups with the same dose of Genistein but along with continuous 2Gy was more significant. In one day treatment regimen, 10x0.2Gy ultra-fractionation with 3 minutes and 1 hour intervals seems to be less effective than conventional 2Gy irradiation, however adding 50uM Genistein can decrease survival more. Although 2Gy conventional dose plus 50uM Genistein was the most effective regimen. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  10. Evaluation of the counter-regulatory responses to hypoglycaemia in patients with type 1 diabetes during opiate receptor blockade with naltrexone.

    PubMed

    Naik, Sarita; Belfort-DeAguiar, Renata; Sejling, Anne-Sophie; Szepietowska, Barbara; Sherwin, Robert S

    2017-05-01

    Hypoglycaemia is the major limiting factor in achieving optimal glycaemic control in people with type 1 diabetes (T1DM), especially intensively treated patients with impaired glucose counter-regulation during hypoglycaemia. Naloxone, an opiate receptor blocker, has been reported to enhance the acute counter-regulatory response to hypoglycaemia when administered intravenously in humans. The current study was undertaken to investigate the oral formulation of the long-acting opiate antagonist, naltrexone, and determine if it could have a similar effect, and thus might be useful therapeutically in treatment of T1DM patients with a high risk of hypoglycaemia. We performed a randomized, placebo-controlled, double-blinded, cross-over study in which 9 intensively treated subjects with T1DM underwent a 2-step euglycaemic-hypoglycaemic-hyperinsulinaemic clamp on 2 separate occasions. At 12 hours and at 1 hour before the clamp study, participants received 100 mg of naltrexone or placebo orally. Counter-regulatory hormonal responses were assessed at baseline and during each step of the hyperinsulinaemic-clamp. Glucose and insulin levels did not differ significantly between the naltrexone and placebo visits; nor did the glucose infusion rates required to keep glucose levels at target. During hypoglycaemia, naltrexone, in comparison with the placebo group, induced an increase in epinephrine levels ( P  = .05). However, no statistically significant differences in glucagon, cortisol and growth hormone responses were observed. In contrast to the intravenous opiate receptor blocker naloxone, overnight administration of the oral long-acting opiate receptor blocker, naltrexone, at a clinically used dose, had a limited effect on the counter-regulatory response to hypoglycaemia in intensively treated subjects with T1DM. © 2016 John Wiley & Sons Ltd.

  11. Naltrexone treatment reverses astrocyte atrophy and immune dysfunction in self-harming macaques.

    PubMed

    Lee, Kim M; Chiu, Kevin B; Didier, Peter J; Baker, Kate C; MacLean, Andrew G

    2015-11-01

    The role of glia in the development and treatment of behavioral abnormalities is understudied. Recent reports have observed glial activation in several disorders, including depression, autism spectrum disorders and self-injurious behaviors (SIB). In the current study, we examined SIB in the physiologically and anatomically relevant nonhuman primate (NHP) model. At the Tulane National Primate Research Center (TNPRC), approximately 5% of singly housed macaques develop symptoms of SIB. We have previously demonstrated that naltrexone hydrochloride can be effective in reducing SIB. We have also demonstrated that the astrocytes of animals with SIB are distinctly atrophic and display heightened innate immune activation compared with control animals. We have added a third group of animals (five macaques identified with SIB and treated with oral naltrexone at a dose of 3.2mg/kg) to the previous cohort (six macaques with a history of SIB but not treated, and nine animals with no history of SIB) for this study. Gray and white matter astrocytes from frontal cortical tissue were examined following necropsy. Innate immune activation of astrocytes, which was increased in SIB animals, was markedly decreased in animals receiving naltrexone, as was atrophy of both grey and white matter astrocytes. This was concomitant with improved behavioral correlates. Preventing astrocyte activation in select areas of the brain to reduce injurious behavior is an innovative concept with implications for mental health studies. Differences in multiple areas of primate brain would help determine how self-injurious behavior develops. These studies suggest a stronger role for astrocytes in the cellular events associated with self-injurious behaviors. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Naltrexone potentiates 4-aminopyridine seizures in the rat.

    PubMed

    Mihály, A; Bencsik, K; Solymosi, T

    1990-01-01

    The effects of a pharmacological blockade of the mu opiate receptors on the manifestation of tonic-clonic seizures were investigated in freely moving animals. 4-aminopyridine, a specific blocker of the neuronal K+ channels was used to produce generalized convulsions. After pretreatment of adult rats with 1 mg/kg naltrexone HCl, 3, 5, 7, 9, 14 mg/kg 4-aminopyridine was injected intraperitoneally, and the latencies of the symptoms generated by 4-aminopyridine were measured. Naltrexone HCl decreased these latencies and enhanced the seizures significantly. The experiments provided further evidence for the existence of a tonic anticonvulsant opioid system in the brain.

  13. Effects of Iterative Reconstruction Algorithms on Computer-assisted Detection (CAD) Software for Lung Nodules in Ultra-low-dose CT for Lung Cancer Screening.

    PubMed

    Nomura, Yukihiro; Higaki, Toru; Fujita, Masayo; Miki, Soichiro; Awaya, Yoshikazu; Nakanishi, Toshio; Yoshikawa, Takeharu; Hayashi, Naoto; Awai, Kazuo

    2017-02-01

    This study aimed to evaluate the effects of iterative reconstruction (IR) algorithms on computer-assisted detection (CAD) software for lung nodules in ultra-low-dose computed tomography (ULD-CT) for lung cancer screening. We selected 85 subjects who underwent both a low-dose CT (LD-CT) scan and an additional ULD-CT scan in our lung cancer screening program for high-risk populations. The LD-CT scans were reconstructed with filtered back projection (FBP; LD-FBP). The ULD-CT scans were reconstructed with FBP (ULD-FBP), adaptive iterative dose reduction 3D (AIDR 3D; ULD-AIDR 3D), and forward projected model-based IR solution (FIRST; ULD-FIRST). CAD software for lung nodules was applied to each image dataset, and the performance of the CAD software was compared among the different IR algorithms. The mean volume CT dose indexes were 3.02 mGy (LD-CT) and 0.30 mGy (ULD-CT). For overall nodules, the sensitivities of CAD software at 3.0 false positives per case were 78.7% (LD-FBP), 9.3% (ULD-FBP), 69.4% (ULD-AIDR 3D), and 77.8% (ULD-FIRST). Statistical analysis showed that the sensitivities of ULD-AIDR 3D and ULD-FIRST were significantly higher than that of ULD-FBP (P < .001). The performance of CAD software in ULD-CT was improved by using IR algorithms. In particular, the performance of CAD in ULD-FIRST was almost equivalent to that in LD-FBP. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  14. Opioids and social bonding: naltrexone reduces feelings of social connection

    PubMed Central

    Ray, Lara A.; Irwin, Michael R.; Way, Baldwin M.; Eisenberger, Naomi I.

    2016-01-01

    Close social bonds are critical to a happy and fulfilled life and yet little is known, in humans, about the neurochemical mechanisms that keep individuals feeling close and connected to one another. According to the brain opioid theory of social attachment, opioids may underlie the contented feelings associated with social connection and may be critical to continued bonding. However, the role of opioids in feelings of connection toward close others has only begun to be examined in humans. In a double-blind, placebo-controlled, crossover study of naltrexone (an opioid antagonist), 31 volunteers took naltrexone for 4 days and placebo for 4 days (separated by a 10-day washout period). Participants came to the laboratory once on the last day of taking each drug to complete a task designed to elicit feelings of social connection. Participants also completed daily reports of feelings of social connection while on naltrexone and placebo. In line with hypotheses, and for the first time in humans, results demonstrated that naltrexone (vs placebo) reduced feelings of connection both in the laboratory and in daily reports. These results highlight the importance of opioids for social bonding with close others, lending support to the brain opioid theory of social attachment. PMID:26796966

  15. Effectiveness of Injectable Extended-Release Naltrexone vs Daily Buprenorphine-Naloxone for Opioid Dependence: A Randomized Clinical Noninferiority Trial.

    PubMed

    Tanum, Lars; Solli, Kristin Klemmetsby; Latif, Zill-E-Huma; Benth, Jurate Šaltyte; Opheim, Arild; Sharma-Haase, Kamni; Krajci, Peter; Kunøe, Nikolaj

    2017-12-01

    To date, extended-release naltrexone hydrochloride has not previously been compared directly with opioid medication treatment (OMT), currently the most commonly prescribed treatment for opioid dependence. To determine whether treatment with extended-release naltrexone will be as effective as daily buprenorphine hydrochloride with naloxone hydrochloride in maintaining abstinence from heroin and other illicit substances in newly detoxified individuals. A 12-week, multicenter, outpatient, open-label randomized clinical trial was conducted at 5 urban addiction clinics in Norway between November 1, 2012, and December 23, 2015; the last follow-up was performed on October 23, 2015. A total of 232 adult opioid-dependent (per DSM-IV criteria) individuals were recruited from outpatient addiction clinics and detoxification units and assessed for eligibility. Intention-to-treat analyses of efficacy end points were performed with all randomized participants. Randomization to either daily oral flexible dose buprenorphine-naloxone, 4 to 24 mg/d, or extended-release naltrexone hydrochloride, 380 mg, administered intramuscularly every fourth week for 12 weeks. Primary end points (protocol) were the randomized clinical trial completion rate, the proportion of opioid-negative urine drug tests, and number of days of use of heroin and other illicit opioids. Secondary end points included number of days of use of other illicit substances. Safety was assessed by adverse event reporting. Of 159 participants, mean (SD) age was 36 (8.6) years and 44 (27.7%) were women. Eighty individuals were randomized to extended-release naltrexone and 79 to buprenorphine-naloxone; 105 (66.0%) completed the trial. Retention in the extended-release naltrexone group was noninferior to the buprenorphine-naloxone group (difference, -0.1; with 95% CI, -0.2 to 0.1; P = .04), with mean (SD) time of 69.3 (25.9) and 63.7 (29.9) days, correspondingly (P = .33, log-rank test). Treatment with extended

  16. Opiate Antagonists Do Not Interfere With the Clinical Benefits of Stimulants in ADHD: A Double-Blind, Placebo-Controlled Trial of the Mixed Opioid Receptor Antagonist Naltrexone.

    PubMed

    Spencer, Thomas J; Bhide, Pradeep; Zhu, Jinmin; Faraone, Stephen V; Fitzgerald, Maura; Yule, Amy M; Uchida, Mai; Spencer, Andrea E; Hall, Anna M; Koster, Ariana J; Biederman, Joseph

    Methylphenidate activates μ-opioid receptors, which are linked to euphoria. μ-Opioid antagonists, such as naltrexone, may attenuate the euphoric effects of stimulants, thereby minimizing their abuse potential. This study assessed whether the combination of naltrexone with methylphenidate is well-tolerated while preserving the clinical benefits of stimulants in subjects with attention-deficit/hyperactivity disorder (ADHD). We conducted a 6-week, double-blind, placebo-controlled, randomized clinical trial of naltrexone in adults with DSM-IV ADHD receiving open treatment with a long-acting formulation of methylphenidate from January 2013 to July 2015. Spheroidal Oral Drug Absorption System (SODAS) methylphenidate was administered twice daily, was titrated to approximately 1 mg/kg/d over 3 weeks, and was continued for 3 additional weeks depending on response and adverse effects. Subjects were adults with ADHD preselected for having experienced euphoria with a test dose of immediate-release methylphenidate. The primary outcome measure was the Adult ADHD Investigator Symptom Report Scale (AISRS). Thirty-seven subjects who experienced stimulant-induced (mild) euphoria at a baseline visit were started in the open trial of SODAS methylphenidate and randomly assigned to naltrexone 50 mg or placebo. Thirty-one subjects completed the study through week 3, and 25 completed through week 6. Throughout 6 weeks of blinded naltrexone and open methylphenidate treatment, the coadministration of naltrexone with methylphenidate did not interfere with the clinical effectiveness of methylphenidate for ADHD symptoms. Additionally, the combination of naltrexone and methylphenidate did not produce an increase in adverse events compared with methylphenidate alone. Our findings provide support for the concept of combining opioid receptor antagonists with stimulants to provide an effective stimulant formulation with less abuse potential. ClinicalTrials.gov identifier: NCT01673594​.

  17. An ultra-low-power filtering technique for biomedical applications.

    PubMed

    Zhang, Tan-Tan; Mak, Pui-In; Vai, Mang-I; Mak, Peng-Un; Wan, Feng; Martins, R P

    2011-01-01

    This paper describes an ultra-low-power filtering technique for biomedical applications designated as T-wave sensing in heart-activities detection systems. The topology is based on a source-follower-based Biquad operating in the sub-threshold region. With the intrinsic advantages of simplicity and high linearity of the source-follower, ultra-low-cutoff filtering can be achieved, simultaneously with ultra low power and good linearity. An 8(th)-order 2.4-Hz lowpass filter design example optimized in a 0.35-μm CMOS process was designed achieving over 85-dB dynamic range, 74-dB stopband attenuation and consuming only 0.36 nW at a 3-V supply.

  18. Adoption of Injectable Naltrexone in U.S. Substance Use Disorder Treatment Programs

    PubMed Central

    Aletraris, Lydia; Edmond, Mary Bond; Roman, Paul M

    2015-01-01

    Objective: Medication-assisted treatment for substance use disorders (SUDs) is not widely used in treatment programs. The aims of the current study were to document the prevalence of adoption and implementation of extended-release injectable naltrexone, the newest U.S. Food and Drug Administration–approved medication for alcohol use disorder (AUD), in U.S. treatment programs and to examine associations between organizational and patient characteristics and adoption. Method: The study used interview data from a nationally representative sample of 307 U.S. SUD treatment programs to examine adoption and implementation of injectable naltrexone. Results: Thirteen percent of programs used injectable naltrexone for AUD, and 3% of programs used it for opioid use disorder. Every treatment program that offered injectable naltrexone to its patients used it in conjunction with psychosocial treatment, particularly cognitive behavioral therapy. Multivariate logistic regression results indicated that adoption was positively associated with the provision of wraparound services, the percentage of privately insured patients, and the presence of inpatient detoxification services. For-profit status and offering inpatient services were negatively associated with adoption. Within adopting programs, an average of 4.1% of AUD patients and 7.1% of patients with opioid use disorder were currently receiving the medication, despite clinical directors’ reports of positive patient outcomes, particularly for relapsers and for those who had been noncompliant with other medications. Cost was a significant issue for the majority of adopting organizations. Conclusions: The rate of adoption of injectable naltrexone in U.S. treatment programs remains limited. Researchers should continue to examine patient, organizational, and external characteristics associated with the adoption and implementation of injectable naltrexone over time. PMID:25486403

  19. Feasibility of ultra low-dose thallium stress-redistribution protocol including prone imaging in obese patients using CZT camera.

    PubMed

    Kincl, Vladimír; Kamínek, Milan; Vašina, Jiří; Panovský, Roman; Havel, Martin

    2016-09-01

    High efficiency cadmium-zinc-telluride (CZT) cameras provide an opportunity to lower the injected activities of radiopharmaceuticals for single photon emission tomography (SPECT) myocardial perfusion imaging (MPI). The limits for reducing activities of thallium have not been determined, particularly in obese patients. After an injection of 0.7 megabecquerel (MBq) of thallium/kg, we collected an average 1.5 million counts for the 10-min acquisition in a pilot cohort of ten patients. After extrapolation, we reduced the administered activity to 0.5 MBq/kg to obtain the expected 1 million counts. We studied the image quality in 124 patients (86 men, 43 obese with body mass index over 30 kg/m 2 ) referred for MPI. The quality of images was assessed by a number of recorded counts and visually by a four-grade scale (one-poor quality, four-excellent quality). In non-obese and obese patients, the average number of recorded counts was 1.1 vs. 1.07 million counts for the 10-min stress acquisition, 1.04 vs. 1.06 million counts for the 13-min rest acquisition, and the average quality score was 3.97 vs. 3.90, respectively (p = NS).The mean administered activity was 39.2 ± 7 MBq for non-obese and 48.7 ± 6 for obese patients (p < 0.0001), and the calculated effective dose was 4.0 ± 0.7 and 4.9 ± 0.6 mSv respectively (p < 0.0001). The ultra-low-dose thallium stress-redistribution protocol, including post-stress prone imaging, provides good quality of images with a low radiation burden, even in obese patients.

  20. Naltrexone in alcohol dependence: a randomised controlled trial of effectiveness in a standard clinical setting.

    PubMed

    Latt, Noeline C; Jurd, Stephen; Houseman, Jennie; Wutzke, Sonia E

    2002-06-03

    To determine whether naltrexone is beneficial in the treatment of alcohol dependence in the absence of obligatory psychosocial intervention. Multicentre, randomised, double-blind, placebo-controlled trial. Hospital-based drug and alcohol clinics, 18 March 1998 - 22 October 1999. 107 patients (mean age, 45 years) fulfilling Diagnostic and statistical manual of mental disorders (4th edition) criteria for alcohol dependence. Patients with alcohol dependence were randomly allocated to naltrexone (50 mg/day) or placebo for 12 weeks. They were medically assessed, reviewed and advised by one physician, and encouraged to strive for abstinence and attend counselling and/or Alcoholics Anonymous, but this was not obligatory. Relapse rate; time to first relapse; side effects. On an intention-to-treat basis, the Kaplan-Meier survival curve showed a clear advantage in relapse rates for naltrexone over placebo (log-rank test, chi(2)(1) = 4.15; P = 0.042). This treatment effect was most marked in the first 6 weeks of the trial. The median time to relapse was 90 days for naltrexone, compared with 42 days for placebo. In absolute numbers, 19 of 56 patients (33.9%) taking naltrexone relapsed, compared with 27 of 51 patients (52.9%) taking placebo (P = 0.047). Naltrexone was well tolerated. Unlike previous studies, we have shown that naltrexone with adjunctive medical advice is effective in the treatment of alcohol dependence irrespective of whether it is accompanied by psychosocial interventions.

  1. Morbidity after Ultra Low Anterior Resection of the Rectum.

    PubMed

    Straja, N D; Ionescu, S; Brătucu, E; Alecu, M; Simion, L

    2015-01-01

    Anterior resections of the rectum, used as an alternative to amputation of the rectum, are performed more and more frequently, being presently indicated for neoplasms located ata distance of 7 to 4 cm from the anus. Complications of low and ultra low anterior resections are not at all negligible, and local neoplastic recurrence rate is significantly higher than after amputation of the rectum. However, literature data recommends low and ultra low anterior rectal resections, even if sometimes the method indications are pushed to the limit or the interventions are performed at the patient's request, in order to avoid permanent colostomy. The authors of this article aim to outline a true picture of the changes caused by anterior resections of the rectum, low and ultra low, so that, without denying the merits of these resections, the entire postoperative pathology that occurs in these patients is depicted and understood. Ultra low rectal resections, up to 3-4 cm from the anus, bring important morphological and functional changes to the act of defecation and to anal continence. These changes in colo-anal bowel movement have a much higher incidence than postoperative genitourinary disorders. Another important aspect emerging from the present study is related to the increased incidence of anastomotic disunity, stenosis and various degrees of incontinence, complications that often can only be solved by completion of rectum amputation and permanent colostomy. In addition, the functional outcomes of these ultra low resections are not always at the level expected by the patient. Also, in terms of surgical performance, the higher share of specific complications of the procedure raises questions with regard to the technique. For all these reasons the authors consider it necessary to review the lower limit to which an anterior rectal resection can descend. Celsius.

  2. Cancer radiotherapy based on femtosecond IR laser-beam filamentation yielding ultra-high dose rates and zero entrance dose.

    PubMed

    Meesat, Ridthee; Belmouaddine, Hakim; Allard, Jean-François; Tanguay-Renaud, Catherine; Lemay, Rosalie; Brastaviceanu, Tiberius; Tremblay, Luc; Paquette, Benoit; Wagner, J Richard; Jay-Gerin, Jean-Paul; Lepage, Martin; Huels, Michael A; Houde, Daniel

    2012-09-18

    Since the invention of cancer radiotherapy, its primary goal has been to maximize lethal radiation doses to the tumor volume while keeping the dose to surrounding healthy tissues at zero. Sadly, conventional radiation sources (γ or X rays, electrons) used for decades, including multiple or modulated beams, inevitably deposit the majority of their dose in front or behind the tumor, thus damaging healthy tissue and causing secondary cancers years after treatment. Even the most recent pioneering advances in costly proton or carbon ion therapies can not completely avoid dose buildup in front of the tumor volume. Here we show that this ultimate goal of radiotherapy is yet within our reach: Using intense ultra-short infrared laser pulses we can now deposit a very large energy dose at unprecedented microscopic dose rates (up to 10(11) Gy/s) deep inside an adjustable, well-controlled macroscopic volume, without any dose deposit in front or behind the target volume. Our infrared laser pulses produce high density avalanches of low energy electrons via laser filamentation, a phenomenon that results in a spatial energy density and temporal dose rate that both exceed by orders of magnitude any values previously reported even for the most intense clinical radiotherapy systems. Moreover, we show that (i) the type of final damage and its mechanisms in aqueous media, at the molecular and biomolecular level, is comparable to that of conventional ionizing radiation, and (ii) at the tumor tissue level in an animal cancer model, the laser irradiation method shows clear therapeutic benefits.

  3. Meta-analysis of naltrexone and acamprosate for treating alcohol use disorders: When are these medications most helpful?

    PubMed Central

    Maisel, Natalya C.; Blodgett, Janet C.; Wilbourne, Paula L.; Humphreys, Keith; Finney, John W.

    2014-01-01

    Aims Although debates over the efficacy of oral naltrexone and acamprosate in treating alcohol use disorders tend to focus on their global efficacy relative to placebo or their efficacy relative to each other, the underlying reality may be more nuanced. This meta-analysis examined when naltrexone and acamprosate are most helpful by testing: (1) the relative efficacy of each medication given its presumed mechanism of action (reducing heavy drinking versus fostering abstinence) and (2) whether different ways of implementing each medication (required abstinence before treatment, detoxification before treatment, goal of treatment, length of treatment, dosage) moderate its effects. Methods A systematic literature search identified 64 randomized, placebo-controlled, English-language clinical trials completed between 1970 and 2009 focused on acamprosate or naltrexone. Results Acamprosate had a significantly larger effect size than naltrexone on the maintenance of abstinence, and naltrexone had a larger effect size than acamprosate on the reduction of heavy drinking and craving. For naltrexone, requiring abstinence before the trial was associated with larger effect sizes for abstinence maintenance and reduced heavy drinking compared to placebo. For acamprosate, detoxification before medication administration was associated with better abstinence outcomes compared to placebo. Conclusions In treatment for alcohol use disorders, acamprosate has been found to be slightly more efficacious in promoting abstinence and naltrexone slightly more efficacious in reducing heavy drinking and craving. Detoxification before treatment or a longer period of required abstinence before treatment is associated with larger medication effects for acamprosate and naltrexone, respectively. PMID:23075288

  4. Effects of naltrexone are influenced by childhood adversity during negative emotional processing in addiction recovery.

    PubMed

    Savulich, G; Riccelli, R; Passamonti, L; Correia, M; Deakin, J F W; Elliott, R; Flechais, R S A; Lingford-Hughes, A R; McGonigle, J; Murphy, A; Nutt, D J; Orban, C; Paterson, L M; Reed, L J; Smith, D G; Suckling, J; Tait, R; Taylor, E M; Sahakian, B J; Robbins, T W; Ersche, K D

    2017-03-07

    Naltrexone is an opioid receptor antagonist used in the management of alcohol dependence. Although the endogenous opioid system has been implicated in emotion regulation, the effects of mu-opioid receptor blockade on brain systems underlying negative emotional processing are not clear in addiction. Individuals meeting criteria for alcohol dependence alone (n=18, alcohol) and in combination with cocaine and/or opioid dependence (n=21, alcohol/drugs) and healthy individuals without a history of alcohol or drug dependence (n=21) were recruited. Participants were alcohol and drug abstinent before entered into this double-blind, placebo-controlled, randomized, crossover study. Functional magnetic resonance imaging was used to investigate brain response while viewing aversive and neutral images relative to baseline on 50 mg of naltrexone and placebo. We found that naltrexone modulated task-related activation in the medial prefrontal cortex and functional connectivity between the anterior cingulate cortex and the hippocampus as a function of childhood adversity (for aversive versus neutral images) in all groups. Furthermore, there was a group-by-treatment-by-condition interaction in the right amygdala, which was mainly driven by a normalization of response for aversive relative to neutral images under naltrexone in the alcohol/drugs group. We conclude that early childhood adversity is one environmental factor that influences pharmacological response to naltrexone. Pharmacotherapy with naltrexone may also have some ameliorative effects on negative emotional processing in combined alcohol and drug dependence, possibly due to alterations in endogenous opioid transmission or the kappa-opioid receptor antagonist actions of naltrexone.

  5. Effects of naltrexone are influenced by childhood adversity during negative emotional processing in addiction recovery

    PubMed Central

    Savulich, G; Riccelli, R; Passamonti, L; Correia, M; Deakin, J F W; Elliott, R; Flechais, R S A; Lingford-Hughes, A R; McGonigle, J; Murphy, A; Nutt, D J; Orban, C; Paterson, L M; Reed, L J; Smith, D G; Suckling, J; Tait, R; Taylor, E M; Sahakian, B J; Robbins, T W; Ersche, K D

    2017-01-01

    Naltrexone is an opioid receptor antagonist used in the management of alcohol dependence. Although the endogenous opioid system has been implicated in emotion regulation, the effects of mu-opioid receptor blockade on brain systems underlying negative emotional processing are not clear in addiction. Individuals meeting criteria for alcohol dependence alone (n=18, alcohol) and in combination with cocaine and/or opioid dependence (n=21, alcohol/drugs) and healthy individuals without a history of alcohol or drug dependence (n=21) were recruited. Participants were alcohol and drug abstinent before entered into this double-blind, placebo-controlled, randomized, crossover study. Functional magnetic resonance imaging was used to investigate brain response while viewing aversive and neutral images relative to baseline on 50 mg of naltrexone and placebo. We found that naltrexone modulated task-related activation in the medial prefrontal cortex and functional connectivity between the anterior cingulate cortex and the hippocampus as a function of childhood adversity (for aversive versus neutral images) in all groups. Furthermore, there was a group-by-treatment-by-condition interaction in the right amygdala, which was mainly driven by a normalization of response for aversive relative to neutral images under naltrexone in the alcohol/drugs group. We conclude that early childhood adversity is one environmental factor that influences pharmacological response to naltrexone. Pharmacotherapy with naltrexone may also have some ameliorative effects on negative emotional processing in combined alcohol and drug dependence, possibly due to alterations in endogenous opioid transmission or the kappa-opioid receptor antagonist actions of naltrexone. PMID:28267152

  6. Development of in vitro-in vivo correlation of parenteral naltrexone loaded polymeric microspheres.

    PubMed

    Andhariya, Janki V; Shen, Jie; Choi, Stephanie; Wang, Yan; Zou, Yuan; Burgess, Diane J

    2017-06-10

    Establishment of in vitro-in vivo correlations (IVIVCs) for parenteral polymeric microspheres has been very challenging, due to their complex multiphase release characteristics (which is affected by the nature of the drug) as well as the lack of compendial in vitro release testing methods. Previously, a Level A correlation has been established and validated for polymeric microspheres containing risperidone (a practically water insoluble small molecule drug). The objectives of the present study were: 1) to investigate whether a Level A IVIVC can be established for polymeric microspheres containing another small molecule drug with different solubility profiles compared to risperidone; and 2) to determine whether release characteristic differences (bi-phasic vs tri-phasic) between microspheres can affect the development and predictability of IVIVCs. Naltrexone was chosen as the model drug. Three compositionally equivalent formulations of naltrexone microspheres with different release characteristics were prepared using different manufacturing processes. The critical physicochemical properties (such as drug loading, particle size, porosity, and morphology) as well as the in vitro release characteristics of the prepared naltrexone microspheres and the reference-listed drug (Vivitrol®) were determined. The pharmacokinetics of the naltrexone microspheres were investigated using a rabbit model. The obtained pharmacokinetic profiles were deconvoluted using the Loo-Riegelman method, and compared with the in vitro release profiles of the naltrexone microspheres obtained using USP apparatus 4. Level A IVIVCs were established and validated for predictability. The results demonstrated that the developed USP 4 method was capable of detecting manufacturing process related performance changes, and most importantly, predicting the in vivo performance of naltrexone microspheres in the investigated animal model. A critical difference between naltrexone and risperidone loaded

  7. A Comparison of Sexual Side Effects of Antidepressants With and Without Naltrexone.

    PubMed

    Thapa, Mona; Petrakis, Ismene; Ralevski, Elizabeth

    2017-01-01

    The aim of the study was to compare the rate of sexual side effects of the selective serotonin reuptake inhibitor paroxetine versus the tricyclic antidepressant desipramine and to examine the effect of co-prescription of naltrexone on sexual side effects among participants in a randomized clinical trial. This was a secondary analysis (N = 88) of veterans who participated in a 12-week trial. All veterans were randomized into one of four treatment groups: (a) desipramine/naltrexone, (b) desipramine/placebo, (c) paroxetine/naltrexone, and (d) paroxetine/placebo. The main outcome measure was the frequency of sexual side effects consisting of "decreased sex drive" and/or "impotence" reported by veterans at each weekly visit. Approximately 61% of the veterans reported sexual side effects at least once during the trial, and 26.4% reported sexual side effects throughout the study. There were no significant differences in the frequency of sexual side effects among the four treatment groups. The results were similar when the comparison was made between the two antidepressant groups. There were no significant differences in the reporting of sexual side effects between those receiving desipramine and paroxetine. Also, the comparison between naltrexone and placebo did not alter the results. This is the first study to compare frequency of sexual side effect reporting between paroxetine and desipramine. We found no statistically significant differences in sexual side effect reporting between the two antidepressants. Also, the addition of naltrexone did not show any beneficial effect on the sexual side effect profile.

  8. Previous administration of naltrexone did not change synergism between paracetamol and tramadol in mice.

    PubMed

    Miranda, Hugo F; Noriega, Viviana; Prieto, Juan Carlos

    2012-07-01

    In the treatment of acute and chronic pain the most frequently used drugs are nonsteroidal anti-inflammatory drugs (NSAIDs), e.g., paracetamol; opioids, e.g., tramadol, and a group of drugs called coanalgesics or adjuvants (e.g., antidepressants, anticonvulsants). The aim of this work was to determine the nature of the interaction induced by intraperitoneal or intrathecal coadministration of paracetamol and tramadol. The type of interaction was evaluated by means of isobolographic analysis, using the acetic acid writhing test as an algesiometer in mice. In addition, the involvement of opioid receptors in the interaction was studied using naltrexone, a non-selective opioid receptor antagonist. The administration of paracetamol or tramadol induced a dose-dependent antinociceptive activity in the assay. The dose-response curves were characterized by equal efficacy but different potencies, being i.t. paracetamol 11.84 times more potent than i.p. paracetamol, and i.t. tramadol 3.54 times more potent than the i.p. tramadol. The isobolographic analysis indicates a synergistic interaction between the coadministration of i.p. or i.t. paracetamol with tramadol. The interaction index values were similar for the i.p. and i.t. coadministration with values of 0.414 and 0.364, respectively. The different mechanisms of action of paracetamol and tramadol strongly explain the analgesic synergism between them, in agreement with the general theory of drug interaction. This synergic interaction was not modified by the non selective opioid antagonist, naltrexone. This association could be of clinical significance in the treatment of pain with a reduction of doses and adverse effects. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. Ultra-Low-Cost Room Temperature SiC Thin Films

    NASA Technical Reports Server (NTRS)

    Faur, Maria

    1997-01-01

    The research group at CSU has conducted theoretical and experimental research on 'Ultra-Low-Cost Room Temperature SiC Thin Films. The effectiveness of a ultra-low-cost room temperature thin film SiC growth technique on Silicon and Germanium substrates and structures with applications to space solar sells, ThermoPhotoVoltaic (TPV) cells and microelectronic and optoelectronic devices was investigated and the main result of this effort are summarized.

  10. Effects of cannabidiol plus naltrexone on motivation and ethanol consumption.

    PubMed

    Viudez-Martínez, Adrián; García-Gutiérrez, María S; Fraguas-Sánchez, Ana Isabel; Torres-Suárez, Ana Isabel; Manzanares, Jorge

    2018-06-02

    The aim of this study was to explore if the administration of naltrexone (NTX) together with cannabidiol (CBD) may improve the efficacy in reducing alcohol consumption and motivation rather than any of the drugs given separately. The effects of low doses of NTX (0.7 mg/kg; p.o.) and/or CBD (20 mg/kg/day; s.c.) on ethanol consumption and motivation to drink were evaluated in the oral-ethanol self-administration paradigm in C57BL/6 mice. Gene expression analyses of μ opioid receptor (Oprm1) in the nucleus accumbens (NAc), tyrosine hydroxylase (TH) in the ventral tegmental area (VTA) and serotonin 1A receptor (5-HT 1A ) in the dorsal raphe nucleus (DR) were carried out by real-time polymerase chain reaction. The role of 5-HT 1A on the ethanol reduction induced by the administration of CBD + NTX was analysed by using the 5-HT 1A receptor antagonist WAY100635 (0.3 mg/kg, i.p.). The administration of CBD + NTX significantly reduced motivation and ethanol intake in the oral self-administration procedure in a greater proportion than the drugs given alone. Only the combination of both drugs significantly reduced Oprm1, TH and 5-HT 1A gene expressions in the NAc, VTA and DR, respectively. Interestingly, the administration of WAY100635 significantly blocked the actions of CBD + NTX but had no effects by itself. The combination of low doses of CBD plus NTX resulted more effective to reduce ethanol consumption and motivation to drink. These effects, appears to be mediated, at least in part, by 5-HT 1A receptors. This article is protected by copyright. All rights reserved.

  11. [Treatment of a serious autistic disorder in a child with Naltrexone in an oral suspension form].

    PubMed

    Desjardins, S; Doyen, C; Contejean, Y; Kaye, K; Paubel, P

    2009-04-01

    that sometimes includes the administration of psychotropic medication. One of these children presented with a severe autistic disorder according to the Childhood Autism Rating Scale (CARS). Considering ICD-10 criteria, he benefited from a multidisciplinary program, associating cognitive psychotherapy, psychomotor rehabilitation, speech therapy and educational intervention. However, persistent sleep disorder and motor instability led to successive prescriptions of several different psychotropic drugs. Initial treatment by thioridazine (10mg per day) followed by propericiazine (2.5mg per day) improved sleep, but was not efficient in reducing self-mutilating behaviour. A new treatment by risperidone (from 0.5mg to 1.5mg per day) was therefore chosen; however it lost its efficacy after five months. Finally, an anxiolytic (cyamemazine) and a thymoregulator (sodium valproate) were successively tried without yielding any clinical improvement. Owing to the persistence of communication difficulties, major instability, self-mutilating behaviour and heteroaggressiveness, treatment with naltrexone was subsequently chosen with parental consent. In France, naltrexone hydrochloride is only available in tablet form (Nalorex 50mg and Revia 50mg), which is not adapted to children at the efficient dose. Consequently, an oral suspension form marketed in Spain (Antaxone 50mg) was imported, having obtained the Afssaps' (the French drug administration) authorisation for its temporary use. The Connors and Nisonger scales were used as outcome measures of behavioural symptom change. The Conners scale is used to assess attention deficit and hyperactivity, whereas the Nisonger scale analyses social skills and behaviour disorders in children and adolescents with mental retardation. The onset of treatment, at a dose of 1mg/kg/day, led to a transitory increase in negative behaviour. However, a dose of 0.75mg/kg per day subsequently led to significant improvements, as shown by outcome measurements

  12. Note: Ultra-low birefringence dodecagonal vacuum glass cell.

    PubMed

    Brakhane, Stefan; Alt, Wolfgang; Meschede, Dieter; Robens, Carsten; Moon, Geol; Alberti, Andrea

    2015-12-01

    We report on an ultra-low birefringence dodecagonal glass cell for ultra-high vacuum applications. The epoxy-bonded trapezoidal windows of the cell are made of SF57 glass, which exhibits a very low stress-induced birefringence. We characterize the birefringence Δn of each window with the cell under vacuum conditions, obtaining values around 10(-8). After baking the cell at 150 °C, we reach a pressure below 10(-10) mbar. In addition, each window is antireflection coated on both sides, which is highly desirable for quantum optics experiments and precision measurements.

  13. Ultra-Low Loss Waveguides with Application to Photonic Integrated Circuits

    NASA Astrophysics Data System (ADS)

    Bauters, Jared F.

    The integration of photonic components using a planar platform promises advantages in cost, size, weight, and power consumption for optoelectronic systems. Yet, the typical propagation loss of 5-10 dB/m in a planar silica waveguide is nearly five orders-of-magnitude larger than that in low loss optical fibers. For some applications, the miniaturization of the photonic system and resulting smaller propagation lengths from integration are enough to overcome the increase in propagation loss. For other more demanding systems or applications, such as those requiring long optical time delays or high-quality-factor (Q factor) resonators, the high propagation loss can degrade system performance to a degree that trumps the potential advantages offered by integration. Thus, the reduction of planar waveguide propagation loss in a Si3-N4 based waveguide platform is a primary focus of this dissertation. The ultra-low loss stoichiometric Si3-N4 waveguide platform offers the additional advantages of fabrication process stability and repeatability. Yet, active devices such as lasers, amplifiers, and photodetectors have not been monolithically integrated with ultra-low loss waveguides due to the incompatibility of the active and ultra-low loss processing thermal budgets (ultra-low loss waveguides are annealed at temperatures exceeding 1000 °C in order to drive out impurities). So a platform that enables the integration of active devices with the ultra-low losses of the Si3- N4 waveguide platform is this dissertation's second focus. The work enables the future fabrication of sensor, gyroscope, true time delay, and low phase noise oscillator photonic integrated circuits.

  14. Ultra Low Outgassing silicone performance in a simulated space ionizing radiation environment

    NASA Astrophysics Data System (ADS)

    Velderrain, M.; Malave, V.; Taylor, E. W.

    2010-09-01

    The improvement of silicone-based materials used in space and aerospace environments has garnered much attention for several decades. Most recently, an Ultra Low Outgassing™ silicone incorporating innovative reinforcing and functional fillers has shown that silicone elastomers with unique and specific properties can be developed to meet applications requiring stringent outgassing requirements. This paper will report on the next crucial step in qualifying these materials for spacecraft applications requiring chemical and physical stability in the presence of ionizing radiation. As a first step in this process, selected materials were irradiated with Co-60 gamma-rays to simulate the total dose received in near- Earth orbits. The paper will present pre-and post-irradiation response data of Ultra Low Outgassing silicone samples exposed under ambient air environment coupled with measurements of collected volatile condensable material (CVCM) and total mass loss (TML) per the standard conditions in ASTM E 595. The data will show an insignificant effect on the CVCMs and TMLs after exposure to various dosages of gamma radiation. This data may favorably impact new applications for these silicone materials for use as an improved sealant for space solar cell systems, space structures, satellite systems and aerospace systems.

  15. Cigarette Smoking Predicts Differential Benefit from Naltrexone for Alcohol Dependence

    PubMed Central

    Fucito, Lisa M.; Park, Aesoon; Gulliver, Suzy Bird; Mattson, Margaret E.; Gueorguieva, Ralitza V.; O’Malley, Stephanie S.

    2012-01-01

    Background Identifying factors that modify responsiveness to pharmacotherapies for alcohol dependence is important for treatment planning. Cigarette smoking predicts more severe alcohol dependence and poorer treatment response in general. Nevertheless, there is limited research on cigarette smoking as a potential predictor of differential response to pharmacological treatment of alcoholism. Methods We examined the association between cigarette smoking and drinking outcomes in the COMBINE study, a randomized, double-blind placebo-controlled 16-week trial comparing combinations of medications (i.e., acamprosate and naltrexone) and behavioral interventions (i.e., medical management (MM), combined behavioral therapy (CBI)) in 1383 alcohol dependent individuals. Results Smokers (i.e., more than half the sample) significantly differed from nonsmokers on several demographic and drinking-related variables at baseline and generally had poorer treatment outcomes than nonsmokers. However, smokers who received naltrexone had better drinking outcomes than smokers who received placebo, whereas alcohol use among nonsmokers did not vary by naltrexone assignment. This pattern of findings occurred independent of whether patients received CBI or MM and remained after controlling for alcoholism typology and baseline demographic differences. Approximately 9% of smokers quit smoking and an additional 10% reduced their cigarette intake during treatment. Reductions in smoking did not vary by treatment assignment. Conclusions These results suggest that naltrexone may be particularly beneficial for improving alcohol use outcomes in alcohol dependent smokers. Trial Registration The COMBINE Study, NCT000626, http://www.cscc.unc.edu/combine/. PMID:22541040

  16. Sensitivity of neuronal nicotinic acetylcholine receptors to the opiate antagonists naltrexone and naloxone: receptor blockade and up-regulation.

    PubMed

    Almeida, Luis E F; Pereira, Edna F R; Camara, Adriana L; Maelicke, Alfred; Albuquerque, Edson X

    2004-04-19

    In HEK293 cells stably expressing alpha4beta2 nAChRs, naltrexone, but not naloxone, blocked alpha4beta2 nAChRs via an open-channel blocking mechanism. In primary hippocampal cultures, naltrexone inhibited alpha7 nAChRs up-regulated by nicotine, and in organotypic hippocampal cultures naltrexone caused a time-dependent up-regulation of functional alpha7 nAChRs that was detected after removal of the drug. These results indicate that naltrexone could be used as a smoking cessation aid.

  17. Cost-effectiveness of buprenorphine and naltrexone treatments for heroin dependence in Malaysia.

    PubMed

    Ruger, Jennifer Prah; Chawarski, Marek; Mazlan, Mahmud; Ng, Nora; Schottenfeld, Richard

    2012-01-01

    To aid public health policymaking, we studied the cost-effectiveness of buprenorphine, naltrexone, and placebo interventions for heroin dependence in Malaysia. We estimated the cost-effectiveness ratios of three treatments for heroin dependence. We used a microcosting methodology to determine fixed, variable, and societal costs of each intervention. Cost data were collected from investigators, staff, and project records on the number and type of resources used and unit costs; societal costs for participants' time were estimated using Malaysia's minimum wage. Costs were estimated from a provider and societal perspective and reported in 2004 US dollars. Muar, Malaysia. 126 patients enrolled in a randomized, double-blind, placebo-controlled clinical trial in Malaysia (2003-2005) receiving counseling and buprenorphine, naltrexone, or placebo for treatment of heroin dependence. Primary outcome measures included days in treatment, maximum consecutive days of heroin abstinence, days to first heroin use, and days to heroin relapse. Secondary outcome measures included treatment retention, injection drug use, illicit opiate use, AIDS Risk Inventory total score, and drug risk and sex risk subscores. Buprenorphine was more effective and more costly than naltrexone for all primary and most secondary outcomes. Incremental cost-effectiveness ratios were below $50 for primary outcomes, mostly below $350 for secondary outcomes. Naltrexone was dominated by placebo for all secondary outcomes at almost all endpoints. Incremental treatment costs were driven mainly by medication costs, especially the price of buprenorphine. Buprenorphine appears to be a cost-effective alternative to naltrexone that might enhance economic productivity and reduce drug use over a longer term.

  18. Reliability testing of ultra-low noise InGaAs quad photoreceivers

    NASA Astrophysics Data System (ADS)

    Joshi, Abhay M.; Datta, Shubhashish; Prasad, Narasimha; Sivertz, Michael

    2018-02-01

    We have developed ultra-low noise quadrant InGaAs photoreceivers for multiple applications ranging from Laser Interferometric Gravitional Wave Detection, to 3D Wind Profiling. Devices with diameters of 0.5 mm, 1mm, and 2 mm were processed, with the nominal capacitance of a single quadrant of a 1 mm quad photodiode being 2.5 pF. The 1 mm diameter InGaAs quad photoreceivers, using a low-noise, bipolar-input OpAmp circuitry exhibit an equivalent input noise per quadrant of <1.7 pA/√Hz in 2 to 20 MHz frequency range. The InGaAs Quad Photoreceivers have undergone the following reliability tests: 30 MeV Proton Radiation up to a Total Ionizing Dose (TID) of 50 krad, Mechanical Shock, and Sinusoidal Vibration.

  19. Note: Ultra-low birefringence dodecagonal vacuum glass cell

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brakhane, Stefan, E-mail: brakhane@iap.uni-bonn.de; Alt, Wolfgang; Meschede, Dieter

    We report on an ultra-low birefringence dodecagonal glass cell for ultra-high vacuum applications. The epoxy-bonded trapezoidal windows of the cell are made of SF57 glass, which exhibits a very low stress-induced birefringence. We characterize the birefringence Δn of each window with the cell under vacuum conditions, obtaining values around 10{sup −8}. After baking the cell at 150 °C, we reach a pressure below 10{sup −10} mbar. In addition, each window is antireflection coated on both sides, which is highly desirable for quantum optics experiments and precision measurements.

  20. Acute Generalized Erythrodermic Pustular Psoriasis Associated with Bupropion/Naltrexone (Contrave®).

    PubMed

    Singh, Priyanka A; Cassel, Kerry P; Moscati, Ronald M; Eckersley, David

    2017-04-01

    We report a case of erythrodermic pustular psoriasis associated with initiation of bupropion/naltrexone (Contrave®; Orexigen Therapeutics, La Jolla, CA) in a patient with no history of psoriasis. A 55-year-old woman was transferred to our tertiary medical center from a community hospital for possible Stevens-Johnson syndrome 3 weeks after initiation of bupropion/naltrexone. The patient was admitted to the burn unit for wound treatment and hydration. She received intravenous cyclosporine during the admission that resulted in acute kidney injury and the therapy was discontinued. The skin biopsy ruled out Stevens-Johnson syndrome and was more consistent with generalized pustular psoriasis. After discharge, the patient followed up with her dermatologist. She was diagnosed with acute generalized and erythrodermic psoriasis and the patient was restarted on cyclosporine 100 mg twice a day. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Few case reports of bupropion-induced generalized pustular psoriasis and erythrodermic psoriasis in patients with a history of psoriasis have been reported. To our knowledge, acute generalized erythrodermic pustular psoriasis associated with bupropion/naltrexone has not been reported in a patient without history of psoriasis. Due to increases in obesity and increases in prescribing of bupropion/naltrexone SR, health care providers should be aware of this possible severe adverse reaction. Published by Elsevier Inc.

  1. Typical doses and dose rates in studies pertinent to radiation risk inference at low doses and low dose rates

    PubMed Central

    Rühm, Werner; Azizova, Tamara; Bouffler, Simon; Cullings, Harry M; Grosche, Bernd; Little, Mark P; Shore, Roy S; Walsh, Linda; Woloschak, Gayle E

    2018-01-01

    Abstract In order to quantify radiation risks at exposure scenarios relevant for radiation protection, often extrapolation of data obtained at high doses and high dose rates down to low doses and low dose rates is needed. Task Group TG91 on ‘Radiation Risk Inference at Low-dose and Low-dose Rate Exposure for Radiological Protection Purposes’ of the International Commission on Radiological Protection is currently reviewing the relevant cellular, animal and human studies that could be used for that purpose. This paper provides an overview of dose rates and doses typically used or present in those studies, and compares them with doses and dose rates typical of those received by the A-bomb survivors in Japan. PMID:29432579

  2. Cost-Effectiveness of Buprenorphine and Naltrexone Treatments for Heroin Dependence in Malaysia

    PubMed Central

    Ruger, Jennifer Prah; Chawarski, Marek; Mazlan, Mahmud; Ng, Nora; Schottenfeld, Richard

    2012-01-01

    Aims To aid public health policymaking, we studied the cost-effectiveness of buprenorphine, naltrexone, and placebo interventions for heroin dependence in Malaysia. Design We estimated the cost-effectiveness ratios of three treatments for heroin dependence. We used a microcosting methodology to determine fixed, variable, and societal costs of each intervention. Cost data were collected from investigators, staff, and project records on the number and type of resources used and unit costs; societal costs for participants’ time were estimated using Malaysia’s minimum wage. Costs were estimated from a provider and societal perspective and reported in 2004 US dollars. Setting Muar, Malaysia. Participants 126 patients enrolled in a randomized, double-blind, placebo-controlled clinical trial in Malaysia (2003–2005) receiving counseling and buprenorphine, naltrexone, or placebo for treatment of heroin dependence. Measurements Primary outcome measures included days in treatment, maximum consecutive days of heroin abstinence, days to first heroin use, and days to heroin relapse. Secondary outcome measures included treatment retention, injection drug use, illicit opiate use, AIDS Risk Inventory total score, and drug risk and sex risk subscores. Findings Buprenorphine was more effective and more costly than naltrexone for all primary and most secondary outcomes. Incremental cost-effectiveness ratios were below $50 for primary outcomes, mostly below $350 for secondary outcomes. Naltrexone was dominated by placebo for all secondary outcomes at almost all endpoints. Incremental treatment costs were driven mainly by medication costs, especially the price of buprenorphine. Conclusions Buprenorphine appears to be a cost-effective alternative to naltrexone that might enhance economic productivity and reduce drug use over a longer term. PMID:23226534

  3. Endogenous opioids, mu-opiate receptors and chloroquine-induced pruritus: a double-blind comparison of naltrexone and promethazine in patients with malaria fever who have an established history of generalized chloroquine-induced itching.

    PubMed

    Ajayi, A A; Kolawole, B A; Udoh, S J

    2004-12-01

    Chloroquine induces a severe generalized pruritus, in predisposed Black African patients, during treatment of malaria fever, and also in some Caucasian patients treated for rheumatological diseases. We have previously shown that chloroquine may release endogenous opioids and/or interact with micro-opiate receptors in rats, and that both histamine and malaria parasite blood density, contribute to the itching severity in malaria fever in humans. The aim of our present study was to assess and compare the antipruritic efficacy of the micro-opiate receptor antagonist, naltrexone, and the antihistamine, promethazine, in chloroquine treated patients with malaria fever. A double-blind, randomized, parallel group comparison of the chloroquine-induced pruritus intensity and time profile in patients with parasitologically proven malaria fever, who were pretreated with a single dose of either naltrexone 50 mg or promethazine 25 mg orally (six patients each). All patients had an established history of severe pruritus following chloroquine treatment of malaria fever. A self-assessed itching severity score was undertaken at 0, 6, 12, 24, 48 and 72 h after initial chloroquine dosing, and the areas under the pruritus-intensity time curve AUCP0-72 h was determined in each patient and correlated to the malaria parasite density in blood. Both naltrexone and promethazine subjectively reduced itching severity compared with prior historical experience. One patient on naltrexone and two on promethazine never experienced any itching. There was no statistically significant treatment effect, but a significant time effect (P = 0.001, F = 4.77 d.f. 5) by two-way repeated measures ANOVA. The AUCP for naltrexone was 82 +/- 25 units/h, and 57 +/- 34 units/h for promethazine [95% confidence interval for the difference being -73 to 123]. However, the malaria parasite density in the naltrexone group (740 +/- 178 microl(-1)) tended to be higher than in the promethazine group 314 +/- 69 microl(-1) (P

  4. Priori mask guided image reconstruction (p-MGIR) for ultra-low dose cone-beam computed tomography

    NASA Astrophysics Data System (ADS)

    Park, Justin C.; Zhang, Hao; Chen, Yunmei; Fan, Qiyong; Kahler, Darren L.; Liu, Chihray; Lu, Bo

    2015-11-01

    Recently, the compressed sensing (CS) based iterative reconstruction method has received attention because of its ability to reconstruct cone beam computed tomography (CBCT) images with good quality using sparsely sampled or noisy projections, thus enabling dose reduction. However, some challenges remain. In particular, there is always a tradeoff between image resolution and noise/streak artifact reduction based on the amount of regularization weighting that is applied uniformly across the CBCT volume. The purpose of this study is to develop a novel low-dose CBCT reconstruction algorithm framework called priori mask guided image reconstruction (p-MGIR) that allows reconstruction of high-quality low-dose CBCT images while preserving the image resolution. In p-MGIR, the unknown CBCT volume was mathematically modeled as a combination of two regions: (1) where anatomical structures are complex, and (2) where intensities are relatively uniform. The priori mask, which is the key concept of the p-MGIR algorithm, was defined as the matrix that distinguishes between the two separate CBCT regions where the resolution needs to be preserved and where streak or noise needs to be suppressed. We then alternately updated each part of image by solving two sub-minimization problems iteratively, where one minimization was focused on preserving the edge information of the first part while the other concentrated on the removal of noise/artifacts from the latter part. To evaluate the performance of the p-MGIR algorithm, a numerical head-and-neck phantom, a Catphan 600 physical phantom, and a clinical head-and-neck cancer case were used for analysis. The results were compared with the standard Feldkamp-Davis-Kress as well as conventional CS-based algorithms. Examination of the p-MGIR algorithm showed that high-quality low-dose CBCT images can be reconstructed without compromising the image resolution. For both phantom and the patient cases, the p-MGIR is able to achieve a clinically

  5. Skin dose measurement by using ultra-thin TLDs.

    PubMed

    Lin, J P; Chu, T C; Lin, S Y; Liu, M T

    2001-09-01

    The treatment schedule for radiation therapy is often interrupted because of complicated skin reactions. Quantitative information relating beam parameters and skin reactions will be helpful. Measurements were performed for 6-15 MV photons and 6-21 MeV electrons with ultra thin TLD films (GR-200F, surface area 0.5 x 0.5cm2, nominal thickness 5 mg cm(-2)). The skin doses for various field sizes, ranging from 10 x 10 to 40 x 40 cm2, and various incident angles of beam from 0 degrees to 80 degrees were measured. The ratios of skin dose to maximum dose in phantom for 10 x 10 cm2 are 16.10+/-0.68%, 14.03+/-1.04% and 10.59+/-0.64% for 6, 10 and 15 MV, respectively. Such ratios increase with a larger field size. For electrons the ratios are 72.59+/-1.72%, 78.52+/-2.99%, 78.89+/-2.86%, 86.08+/-2.62%. 87.75+/-1.94% and 86.33+/-3.09% for 6, 9, 12, 15, 18 and 21 MeV, respectively. They also increase with a larger size. The oblique factors also increase with larger incident angle.

  6. 21 CFR 522.1465 - Naltrexone hydrochloride injection.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... this chapter. (c) Conditions of use in elk and moose—(1) Amount. 100 milligrams of naltrexone...) Indications for use. As an antagonist to carfentanil citrate immobilization in free-ranging or confined elk and moose (Cervidae). (3) Limitations. Available data are inadequate to recommend use in pregnant...

  7. Ultra-low temperature curable nano-silver conductive adhesive for piezoelectric composite material

    NASA Astrophysics Data System (ADS)

    Yan, Chao; Liao, Qingwei; Zhou, Xingli; Wang, Likun; Zhong, Chao; Zhang, Di

    2018-01-01

    Limited by the low thermal resistance of composite material, ultra-low temperature curable conductive silver adhesive with curing temperature less than 100 °C needed urgently for the surface conduction treatment of piezoelectric composite material. An ultra-low temperature curable nano-silver conductive adhesive with high adhesion strength for the applications of piezoelectric composite material was investigated. The crystal structure of cured adhesive, SEM/EDS analysis, thermal analysis, adhesive properties and conductive properties of different content of nano-silver filler or micron-silver doping samples were studied. The results show that with 60 wt.% nano-silver filler the ultra-low temperature curable conductive silver adhesive had the relatively good conductivity as volume resistivity of 2.37 × 10-4 Ω cm, and good adhesion strength of 5.13 MPa. Minor micron-doping (below 15 wt.%) could improve conductivity, but would decrease other properties. The ultra-low temperature curable nano-silver conductive adhesive could successfully applied to piezoelectric composite material.

  8. Traceable low and ultra-low temperatures in The Netherlands

    NASA Astrophysics Data System (ADS)

    Peruzzi, A.; Bosch, W. A.

    2009-02-01

    The basis for worldwide uniformity of low and ultra-low temperature measurements is provided by two international temperature scales, the International Temperature Scale of 1990 (ITS-90) for temperatures above 0.65 K and the Provisional Low Temperature Scale of 2000 (PLTS-2000) for temperatures in the range 0.9 mK to 1 K. Over the past 10 years, the thermometry research in the Netherlands provided substantial contributions to the definition, realization and dissemination of these scales. We first give an overview of the Dutch contributions to the ITS-90 realization: a) 3He and 4He vapour pressure thermometer range of the ITS-90, 0.65 K to 4 K (1997), b) 4He interpolating constant volume gas thermometry for the ITS-90 range 3 K to 24.5 K (2007) and c) cryogenic fixed points for the ITS-90 range 13.8 K to 273.16 K (2005). Then we highlight our work on 3He melting pressure thermometry from 10 mK to 1 K (2003) to support the dissemination of the PLTS-2000. Finally we present the current status of the Dutch calibration facilities and dissemination devices providing for traceable low and ultra-low temperatures for use in science and industry: a) the NMi-VSL cryogenic calibration facility for the range 0.65 K to 273.16 K and b) the SRD1000 superconductive reference devices for the range 10 mK to 1 K.

  9. Differential renal effects of candesartan at high and ultra-high doses in diabetic mice–potential role of the ACE2/AT2R/Mas axis

    PubMed Central

    Callera, Glaucia E.; Antunes, Tayze T.; Correa, Jose W.; Moorman, Danielle; Gutsol, Alexey; He, Ying; Cat, Aurelie Nguyen Dinh; Briones, Ana M.; Montezano, Augusto C.; Burns, Kevin D.; Touyz, Rhian M.

    2016-01-01

    High doses of Ang II receptor (AT1R) blockers (ARBs) are renoprotective in diabetes. Underlying mechanisms remain unclear. We evaluated whether high/ultra-high doses of candesartan (ARB) up-regulate angiotensin-converting enzyme 2 (ACE2)/Ang II type 2 receptor (AT2R)/Mas receptor [protective axis of the of the renin–angiotensin system (RAS)] in diabetic mice. Systolic blood pressure (SBP), albuminuria and expression/activity of RAS components were assessed in diabetic db/db and control db/+ mice treated with increasing candesartan doses (intermediate, 1 mg/kg/d; high, 5 mg/kg/d; ultra-high, 25 and 75 mg/kg/d; 4 weeks). Lower doses candesartan did not influence SBP, but ultra-high doses reduced SBP in both groups. Plasma glucose and albuminuria were increased in db/db compared with db/+ mice. In diabetic mice treated with intermediate dose candesartan, renal tubular damage and albuminuria were ameliorated and expression of ACE2, AT2R and Mas and activity of ACE2 were increased, effects associated with reduced ERK1/2 phosphorylation, decreased fibrosis and renal protection. Ultra-high doses did not influence the ACE2/AT2R/Mas axis and promoted renal injury with increased renal ERK1/2 activation and exaggerated fibronectin expression in db/db mice. Our study demonstrates dose-related effects of candesartan in diabetic nephropathy: intermediate–high dose candesartan is renoprotective, whereas ultra-high dose candesartan induces renal damage. Molecular processes associated with these effects involve differential modulation of the ACE2/AT2R/Mas axis: intermediate–high dose candesartan up-regulating RAS protective components and attenuating pro-fibrotic processes, and ultra-high doses having opposite effects. These findings suggest novel mechanisms through the protective RAS axis, whereby candesartan may ameliorate diabetic nephropathy. Our findings also highlight potential injurious renal effects of ultra-high dose candesartan in diabetes. PMID:27612496

  10. Low-Dose Carcinogenicity Studies

    EPA Science Inventory

    One of the major deficiencies of cancer risk assessments is the lack of low-dose carcinogenicity data. Most assessments require extrapolation from high to low doses, which is subject to various uncertainties. Only 4 low-dose carcinogenicity studies and 5 low-dose biomarker/pre-n...

  11. RuO2 Thermometer for Ultra-Low Temperatures

    NASA Technical Reports Server (NTRS)

    Hait, Thomas; Shirron, Peter J.; DiPirro, Michael

    2009-01-01

    A small, high-resolution, low-power thermometer has been developed for use in ultra-low temperatures that uses multiple RuO2 chip resistors. The use of commercially available thick-film RuO2 chip resistors for measuring cryogenic temperatures is well known due to their low cost, long-term stability, and large resistance change.

  12. Comparison of image quality, myocardial perfusion, and LV function between standard imaging and single-injection ultra-low-dose imaging using a high-efficiency SPECT camera: the MILLISIEVERT study

    PubMed Central

    Einstein, Andrew J.; Blankstein, Ron; Andrews, Howard; Fish, Mathews; Padgett, Richard; Hayes, Sean W.; Friedman, John D.; Qureshi, Mehreen; Rakotoarivelo, Harivony; Slomka, Piotr; Nakazato, Ryo; Bokhari, Sabahat; Di Carli, Marcello; Berman, Daniel S.

    2015-01-01

    SPECT myocardial perfusion imaging (MPI) plays a central role in coronary artery disease diagnosis; but concerns exist regarding its radiation burden. Compared to standard Anger-SPECT (A-SPECT) cameras, new high-efficiency (HE) cameras with specialized collimators and solid-state cadmium-zinc-telluride detectors offer potential to maintain image quality (IQ), while reducing administered activity and thus radiation dose to patients. No previous study has compared IQ, interpretation, total perfusion deficit (TPD), or ejection fraction (EF) in patients receiving both ultra-low-dose (ULD) imaging on a HE-SPECT camera and standard low-dose (SLD) A-SPECT imaging. Methods We compared ULD-HE-SPECT to SLD-A-SPECT imaging by dividing the rest dose in 101 patients at 3 sites scheduled to undergo clinical A-SPECT MPI using a same day rest/stress Tc-99m protocol. Patients received HE-SPECT imaging following an initial ~130 MBq (3.5mCi) dose, and SLD-A-SPECT imaging following the remainder of the planned dose. Images were scored visually by 2 blinded readers for IQ and summed rest score (SRS). TPD and EF were assessed quantitatively. Results Mean activity was 134 MBq (3.62 mCi) for ULD-HE-SPECT (effective dose 1.15 mSv) and 278 MBq (7.50 mCi, 2.39 mSv) for SLD-A-SPECT. Overall IQ was superior for ULD-HE-SPECT (p<0.0001), with twice as many studies graded excellent quality. Extracardiac activity and overall perfusion assessment were similar. Between-method correlations were high for SRS (r=0.87), TPD (r=0.91), and EF (r=0.88). Conclusion ULD-HE-SPECT rest imaging correlates highly with SLD-A-SPECT. It has improved image quality, comparable extracardiac activity, and achieves radiation dose reduction to 1 mSv for a single injection. PMID:24982439

  13. An ultra-low power output capacitor-less low-dropout regulator with slew-rate-enhanced circuit

    NASA Astrophysics Data System (ADS)

    Cheng, Xin; Zhang, Yu; Xie, Guangjun; Yang, Yizhong; Zhang, Zhang

    2018-03-01

    An ultra-low power output-capacitorless low-dropout (LDO) regulator with a slew-rate-enhanced (SRE) circuit is introduced. The increased slew rate is achieved by sensing the transient output voltage of the LDO and then charging (or discharging) the gate capacitor quickly. In addition, a buffer with ultra-low output impedance is presented to improve line and load regulations. This design is fabricated by SMIC 0.18 μm CMOS technology. Experimental results show that, the proposed LDO regulator only consumes an ultra-low quiescent current of 1.2 μA. The output current range is from 10 μA to 200 mA and the corresponding variation of output voltage is less than 40 mV. Moreover, the measured line regulation and load regulation are 15.38 mV/V and 0.4 mV/mA respectively. Project supported by the National Natural Science Foundation of China (Nos. 61401137, 61404043, 61674049).

  14. Clinical Effects of Naltrexone on Autistic Behavior.

    ERIC Educational Resources Information Center

    Zingarelli, Gene; And Others

    1992-01-01

    Eight young adults (ages 19-39) with autism were given the opiate antagonist naltrexone to control self-injurious behavior and maladaptive idiosyncratic mannerisms. Although one subject appeared to have partial decreases in maladaptive behaviors, the drug did not clearly reduce the self-injurious and other maladaptive behaviors of the subjects.…

  15. Whole-body ultra-low dose CT using spectral shaping for detection of osteolytic lesion in multiple myeloma.

    PubMed

    Suntharalingam, Saravanabavaan; Mikat, Christian; Wetter, Axel; Guberina, Nika; Salem, Ahmed; Heil, Philipp; Forsting, Michael; Nassenstein, Kai

    2018-06-01

    The aim of this study was to investigate the radiation dose and image quality of a whole-body low-dose CT (WBLDCT) using spectral shaping at 100 kV (Sn 100 kV) for the assessment of osteolytic lesions in patients with multiple myeloma. Thirty consecutive patients were retrospectively selected, who underwent a WBLDCT on a third-generation dual-source CT (DSCT) (Sn 100 kV, ref. mAs: 130). They were matched with patients, who were examined on a second-generation DSCT with a standard low-dose protocol (100 kV, ref. mAs: 111). Objective and subjective image quality, radiation exposure as well as the frequency of osteolytic lesions were evaluated. All scans were of diagnostic image quality. Subjective overall image quality was significantly higher in the study group (p = 0.0003). Objective image analysis revealed that signal intensities, signal-to-noise ratio and contrast-to-noise ratio of the bony structures were equal or significantly higher in the control group. There was no significant difference in the frequency of osteolytic lesions (p = 0.259). The median effective dose of the study protocol was significantly lower (1.45 mSv vs. 5.65 mSv; p < 0.0001). WBLDCT with Sn 100 kV can obtain sufficient image quality for the depiction of osteolytic lesions while reducing the radiation dose by approximately 74%. • Spectral shaping using tin filtration is beneficial for whole-body low-dose CT • Sn 100 kV yields sufficient image quality for depiction of osteolytic lesions • Whole-body low-dose CT can be performed with a median dose of 1.5 mSv.

  16. Safety assessment of combination therapies in the treatment of obesity: focus on naltrexone/bupropion extended release and phentermine-topiramate extended release.

    PubMed

    Halpern, Bruno; Mancini, Marcio C

    2017-01-01

    Few studies on combination therapies for the treatment of obesity had been conducted until recently, when two fixed-dose combinations, bupropion-naltrexone ER fixed-dose combination and phentermine-topiramate ER titrated-dose combinations were evaluated in clinical studies that ultimately led to FDA approval. Areas covered: In this review, we discuss safety concerns about both combinations, the rationale and history of combination therapies for obesity (including phentermine plus fenfluramine), and possible future new combinations. Expert opinion: Combination therapies are a promising new area in obesity treatment, similar to what occurs with diabetes and hypertension. Safety assessment is highly important due to the high number of potential users on a chronic basis.

  17. Ultra-low dose quantitative CT myocardial perfusion imaging with sparse-view dynamic acquisition and image reconstruction: A feasibility study.

    PubMed

    Enjilela, Esmaeil; Lee, Ting-Yim; Hsieh, Jiang; Wisenberg, Gerald; Teefy, Patrick; Yadegari, Andrew; Bagur, Rodrigo; Islam, Ali; Branch, Kelley; So, Aaron

    2018-03-01

    We implemented and validated a compressed sensing (CS) based algorithm for reconstructing dynamic contrast-enhanced (DCE) CT images of the heart from sparsely sampled X-ray projections. DCE CT imaging of the heart was performed on five normal and ischemic pigs after contrast injection. DCE images were reconstructed with filtered backprojection (FBP) and CS from all projections (984-view) and 1/3 of all projections (328-view), and with CS from 1/4 of all projections (246-view). Myocardial perfusion (MP) measurements with each protocol were compared to those with the reference 984-view FBP protocol. Both the 984-view CS and 328-view CS protocols were in good agreements with the reference protocol. The Pearson correlation coefficients of 984-view CS and 328-view CS determined from linear regression analyses were 0.98 and 0.99 respectively. The corresponding mean biases of MP measurement determined from Bland-Altman analyses were 2.7 and 1.2ml/min/100g. When only 328 projections were used for image reconstruction, CS was more accurate than FBP for MP measurement with respect to 984-view FBP. However, CS failed to generate MP maps comparable to those with 984-view FBP when only 246 projections were used for image reconstruction. DCE heart images reconstructed from one-third of a full projection set with CS were minimally affected by aliasing artifacts, leading to accurate MP measurements with the effective dose reduced to just 33% of conventional full-view FBP method. The proposed CS sparse-view image reconstruction method could facilitate the implementation of sparse-view dynamic acquisition for ultra-low dose CT MP imaging. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. High-power all-fiber ultra-low noise laser

    NASA Astrophysics Data System (ADS)

    Zhao, Jian; Guiraud, Germain; Pierre, Christophe; Floissat, Florian; Casanova, Alexis; Hreibi, Ali; Chaibi, Walid; Traynor, Nicholas; Boullet, Johan; Santarelli, Giorgio

    2018-06-01

    High-power ultra-low noise single-mode single-frequency lasers are in great demand for interferometric metrology. Robust, compact all-fiber lasers represent one of the most promising technologies to replace the current laser sources in use based on injection-locked ring resonators or multi-stage solid-state amplifiers. Here, a linearly polarized high-power ultra-low noise all-fiber laser is demonstrated at a power level of 100 W. Special care has been taken in the study of relative intensity noise (RIN) and its reduction. Using an optimized servo actuator to directly control the driving current of the pump laser diode, we obtain a large feedback bandwidth of up to 1.3 MHz. The RIN reaches - 160 dBc/Hz between 3 and 20 kHz.

  19. Real-time assessment of alcohol craving and naltrexone treatment responsiveness in a randomized clinical trial.

    PubMed

    Miranda, Robert; Treloar Padovano, Hayley; Gray, Joshua C; Wemm, Stephanie E; Blanchard, Alexander

    2018-08-01

    This secondary data analysis examined whether and how the dopamine receptor D 4 gene (DRD4) influenced naltrexone treatment responsiveness in a randomized clinical trial. We leveraged intensive experience sampling methods to test the hypothesis that craving recorded at drinking and non-drinking moments would mediate naltrexone effects on the likelihood of heavy drinking, but only among carriers of the DRD4 long (DRD4-L) allele. Participants (M age =29.8years, SD=12.1) were non-treatment seeking heavy drinkers (n=104, 54.8% female, 61.5% alcohol dependent) randomized to 3weeks of daily naltrexone (50mg) or placebo. During these 3weeks, participants used handheld electronic devices to complete real-time reports of alcohol use and craving multiple times per day in their natural environments. This approach afforded intensive repeated assessment of focal variables and provided in-the-moment data to test whether craving when not drinking or early in drinking episodes explained naltrexone effects on drinking. Moderated-mediation multilevel structural equation models showed that craving during non-drinking moments mediated the treatment effect of naltrexone on heavy drinking but only among carriers of the DRD4-L allele. The same pattern of associations was not shown when evaluating craving while participants were consuming alcoholic beverages. Findings provide the first in vivo evidence that, among carriers of the DRD4-L allele, naltrexone blunts craving in real-world settings, and this effect in turn reduces the likelihood of heavy drinking. This work highlights the utility of EMA methods for elucidating how treatments work and further demonstrates the importance of genetic factors for understanding individual differences in pharmacotherapy responsiveness. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Low-dose estrogen therapy for prevention of osteoporosis: working our way back to monotherapy.

    PubMed

    Richman, Susan; Edusa, Valentine; Fadiel, Ahmed; Naftolin, Frederick

    2006-01-01

    The risks of low bone mineral density, osteoporosis and fractures, are major concerns in postmenopausal women. Although postmenopausal hormone therapy is effective for reducing these risks, safety issues have been raised by the results of studies such as the Women's Health Initiative. Although there are scientifically valid reasons to be wary of the general applicability of the Women's Health Initiative findings, the study has underscored the continuing need for research into new forms of menopausal hormone therapy. Low-dose transdermal estrogen monotherapy can preserve bone density while relieving vasomotor symptoms. Transdermal administration may offer advantages, including lack of first-pass liver metabolism, which permits the use of lower doses and avoids a negative impact on the lipid profile. Moreover, a recently published 2-year study of ultra-low-dose transdermal estrogen monotherapy in an older population similar to that of the WHI reported significant increases in bone mineral density, accompanied by significant reductions in markers of bone turnover, with no increased risk of endometrial hyperplasia or other side effects. Additional studies are warranted to shed further light on the possible benefits of low-dose estrogen monotherapy for the prevention of bone loss in postmenopausal women.

  1. What role does measuring medication compliance play in evaluating the efficacy of naltrexone?

    PubMed

    Baros, Alicia M; Latham, Patricia K; Moak, Darlene H; Voronin, Konstantin; Anton, Raymond F

    2007-04-01

    Compliance with medication in pharmacotherapy trials of alcoholism has been shown to be equal to, or more, important than in other areas of medicine. Research has suggested that naltrexone's effectiveness can be greatly influenced by the compliance of participants in clinical trials. Presently, we compare 2 compliance measurement methods [urine riboflavin and medication event monitoring system (MEMS)] used simultaneously to evaluate naltrexone's efficacy and the impact of compliance on the size of observable treatment effects. One hundred and thirty-seven of 160 randomized alcoholic patients completed 12-weeks (84 days) of naltrexone or placebo and cognitive behavioral therapy (CBT) or motivational enhancement therapy (MET). Urine riboflavin was determined during study weeks 2, 6, and 12. The MEMS provided a detailed computerized record of when a participant opened their medication bottle throughout the trial. Baseline predictors of MEMS (80% openings) and urine riboflavin (>or=1,500 ng/mL by fluorimetry) compliance were examined. The effects of the treatments in the compliant participants defined by one, the other, or both methods were compared and contrasted with a previously reported intent-to-treat analysis where compliance was not taken into account. Age was predictive of compliance. 105 participants were deemed compliant via urine riboflavin criteria, 87 via MEMS, and 77 when both criteria were met, with no significant differences between treatment groups. The most compliant participants showed a significant medication by therapy interaction. Those treated with naltrexone/CBT showed more abstinence days (p<0.03), less heavy drinking days (p<0.03) and less total drinks (p<0.03) than the other groups. The effect size of this interaction increased from about 0.2 in the intent-to-treat analysis, to about 0.4 to 0.5 in the compliant group analyses, with little difference between compliance measurement methods. Compliance measurement does appear to influence the

  2. Ultra-low magnetic damping in metallic and half-metallic systems

    NASA Astrophysics Data System (ADS)

    Shaw, Justin

    The phenomenology of magnetic damping is of critical importance to devices which seek to exploit the electronic spin degree of freedom since damping strongly affects the energy required and speed at which a device can operate. However, theory has struggled to quantitatively predict the damping, even in common ferromagnetic materials. This presents a challenge for a broad range of applications in magnonics, spintronics and spin-orbitronics that depend on the ability to precisely control the damping of a material. I will discuss our recent work to precisely measure the intrinsic damping in several metallic and half-metallic material systems and compare experiment with several theoretical models. This investigation uncovered a metallic material composed of Co and Fe that exhibit ultra-low values of damping that approach values found in thin film YIG. Such ultra-low damping is unexpected in a metal since magnon-electron scattering dominates the damping in conductors. However, this system possesses a distinctive feature in the bandstructure that minimizes the density of states at the Fermi energy n(EF). These findings provide the theoretical framework by which such ultra-low damping can be achieved in metallic ferromagnets and may enable a new class of experiments where ultra-low damping can be combined with a charge current. Half-metallic Heusler compounds by definition have a bandgap in one of the spin channels at the Fermi energy. This feature can also lead to exceptionally low values of the damping parameter. Our results show a strong correlation of the damping with the order parameter in Co2MnGe. Finally, I will provide an overview of the recent advances in achieving low damping in thin film Heusler compounds.

  3. Evaluation of an Ultra-Low Power Reed Solomon Encoder for NASA's Space Technology 5 Mission

    NASA Technical Reports Server (NTRS)

    Lei, K. E.; Xapsos, M. A.; Poivey, C.; LaBel, K. A.; Stone, R. F.; Yeh, P-S.; Gambles, J.; Hass, J.; Maki, G.; Murguia, J.

    2003-01-01

    Radiation test results and analyses are presented for ultra-low power Reed Solomon encoder circuits that are being considered for use on the Space Technology 5 (ST5) mission. The total ionizing dose tolerance is in excess of 100 krad(Si) and is due to the low supply voltage and the use of back-bias, which suppresses radiation-induced leakage currents in the n-channel devices. The circuits do not latch-up for ion LET values of at least 90 MeV-sq cm/mg. A hardened-by-design approach to SEU has achieved an upset threshold of about 20 MeV-sq cm/mg. The SEU rate expected for these circuits in the geosynchronous transfer orbit of ST5 is low.

  4. Background characterization of an ultra-low background liquid scintillation counter

    DOE PAGES

    Erchinger, J. L.; Orrell, John L.; Aalseth, C. E.; ...

    2017-01-26

    The Ultra-Low Background Liquid Scintillation Counter developed by Pacific Northwest National Laboratory will expand the application of liquid scintillation counting by enabling lower detection limits and smaller sample volumes. By reducing the overall count rate of the background environment approximately 2 orders of magnitude below that of commercially available systems, backgrounds on the order of tens of counts per day over an energy range of ~3–3600 keV can be realized. Finally, initial test results of the ULB LSC show promising results for ultra-low background detection with liquid scintillation counting.

  5. Randomized controlled trial of a mobile phone intervention for improving adherence to naltrexone for alcohol use disorders.

    PubMed

    Stoner, Susan A; Arenella, Pamela B; Hendershot, Christian S

    2015-01-01

    Naltrexone is a front-line treatment for alcohol use disorders, but its efficacy is limited by poor medication adherence. This randomized controlled trial evaluated whether a mobile health intervention could improve naltrexone adherence. Treatment-seeking participants with an alcohol use disorder (N = 76) were randomized to intervention and control conditions. All participants received naltrexone (50 mg/day) with a medication event monitoring system (MEMS) and a prepaid smartphone, and received a daily text message querying medication side effects, alcohol use, and craving. Those in the intervention arm received additional medication reminders and adherence assessment via text message. The primary outcome, proportion of participants with adequate adherence (defined as ≥80% of prescribed doses taken through Week 8), did not differ between groups in intent-to-treat analyses (p = .34). Mean adherence at study midpoint (Week 4) was 83% in the intervention condition and 77% in the control condition (p = .35). Survival analysis found that the intervention group sustained adequate adherence significantly longer (M = 19 days [95% CI = 0.0-44.0]) than those in the control group (M = 3 days [95% CI = 0.0-8.1]) during the first month of treatment (p = .04). Medication adherence did not predict drinking outcomes. These results suggest that in the context of daily monitoring and assessment via cell phone, additional text message reminders do not further improve medication adherence. Although this initial trial does not provide support for the efficacy of text messaging to improve adherence to pharmacotherapy for alcohol use disorders, additional trials with larger samples and alternate designs are warranted. ClinicalTrials.gov: NCT01349985.

  6. Ultra-thin smart acoustic metasurface for low-frequency sound insulation

    NASA Astrophysics Data System (ADS)

    Zhang, Hao; Xiao, Yong; Wen, Jihong; Yu, Dianlong; Wen, Xisen

    2016-04-01

    Insulating low-frequency sound is a conventional challenge due to the high areal mass required by mass law. In this letter, we propose a smart acoustic metasurface consisting of an ultra-thin aluminum foil bonded with piezoelectric resonators. Numerical and experimental results show that the metasurface can break the conventional mass law of sound insulation by 30 dB in the low frequency regime (<1000 Hz), with an ultra-light areal mass density (<1.6 kg/m2) and an ultra-thin thickness (1000 times smaller than the operating wavelength). The underlying physical mechanism of such extraordinary sound insulation performance is attributed to the infinite effective dynamic mass density produced by the smart resonators. It is also demonstrated that the excellent sound insulation property can be conveniently tuned by simply adjusting the external circuits instead of modifying the structure of the metasurface.

  7. Naltrexone Alone and With Sertraline for the Treatment of Alcohol Dependence in Alaska Natives and Non-Natives Residing in Rural Settings: A Randomized Controlled Trial

    PubMed Central

    O’Malley, Stephanie S.; Robin, Robert W.; Levenson, Aryeh L.; GreyWolf, Iva; Chance, Lawrence E.; Hodgkinson, Colin A.; Romano, Denise; Robinson, Jane; Meandzija, Boris; Stillner, Verner; Wu, Ran; Goldman, David

    2009-01-01

    Background Access to specialty alcoholism treatment in rural environments is limited and new treatment approaches are needed. The objective was to evaluate the efficacy of naltrexone alone and in combination with sertraline among Alaska Natives and other Alaskans living in rural settings. An exploratory aim examined whether the Asn40Asp polymorphism of the μ-opioid receptor gene (OPRMI) predicted response to naltrexone, as had been reported in Caucasians. Methods Randomized, controlled trial enrolling 101 Alaskans with alcohol dependence, including 68 American Indians/Alaska Natives. Participants received 16 weeks of either (1) placebo (placebo naltrexone + placebo sertraline), (2) naltrexone monotherapy (50 mg naltrexone + sertraline placebo) and (3) naltrexone + sertraline (100 mg) plus nine sessions of medical management and supportive advice. Primary outcomes included Time to First Heavy Drinking Day and Total Abstinence. Results Naltrexone monotherapy demonstrated significantly higher total abstinence (35%) compared with placebo (12%, p = 0027) and longer, but not statistically different, Time to First Heavy Drinking Day (p = 0.093). On secondary measures, naltrexone compared with placebo demonstrated significant improvements in percent days abstinent (p = 0.024) and drinking-related consequences (p = 0.02). Combined sertraline and naltrexone did not differ from naltrexone alone. The pattern of findings was generally similar for the American Indian/Alaska Native sub-sample. Naltrexone treatment response was significant within the group of 75 individuals who were homozygous for OPRM1 Asn40 allele. There was a small number of Asp40 carriers, precluding statistical testing of the effect of this allele on response. Conclusions Naltrexone can be used effectively to treat alcoholism in remote and rural communities, with evidence of benefit for American Indians and Alaska Natives. New models of care incorporating pharmacotherapy could reduce important health

  8. Tribological performance of ultra-low viscosity composite base fluid with bio-derived fluid

    USDA-ARS?s Scientific Manuscript database

    One obvious approach to increase efficiencies in many lubricated systems such as ICE and gearbox is the reduction in viscosity of oil lubricant. Indeed, ultra-low viscosity engine oils are now commercially available. One approach to the development of ultra-low viscosity lubricants without compromis...

  9. FORMULATING ULTRA-LOW-VOC WOOD FURNITURE COATINGS

    EPA Science Inventory

    The article discusses the formulation of ultra-low volatile organic compound (VOC) wood furniture coatings. The annual U.S. market for wood coatings is about 240, 000 cu m (63 million gal). In this basis, between 57 and 91 million kg (125 and 200 million lb) of VOCs are emitted i...

  10. Organizational-Level Predictors of Adoption Across Time: Naltrexone in Private Substance-Use Disorders Treatment Centers*

    PubMed Central

    Oser, Carrie B.; Roman, Paul M.

    2014-01-01

    Objective Prominent on the nation's research agenda on substance-use disorders treatment is the dissemination of effective pharmacotherapies. Thus, the purpose of this article is to use a “diffusion of innovations” theoretical framework to examine the organizational-level predictors of the adoption of a pharmacotherapy, naltrexone (Revia), in private substance use-disorders treatment centers (N = 165). Method Data for these analyses were derived from the National Treatment Center Study, which contains four waves of data collected between 1994 and 2003. An event history model examined the impact of culture, leadership characteristics, internal structure, and external characteristics on the likelihood of adopting naltrexone between 1994 and 2003. Results The results suggest that organizations embracing a 12-step model and those employing more experienced administrators were significantly less likely to adopt naltrexone. Moreover, treatment centers that used prescription drugs, possessed an employee handbook, were accredited, and operated on a for-profit basis were significantly more likely to adopt naltrexone over time. Conclusions Structural characteristics do affect the innovation adoption behaviors of private substance-use disorders treatment centers. Organizational-level “research to practice” implications to further the adoption of innovative evidence-based treatments are discussed. PMID:17960303

  11. Ultra Low Energy Binary Decision Diagram Circuits Using Few Electron Transistors

    NASA Astrophysics Data System (ADS)

    Saripalli, Vinay; Narayanan, Vijay; Datta, Suman

    Novel medical applications involving embedded sensors, require ultra low energy dissipation with low-to-moderate performance (10kHz-100MHz) driving the conventional MOSFETs into sub-threshold operation regime. In this paper, we present an alternate ultra-low power computing architecture using Binary Decision Diagram based logic circuits implemented using Single Electron Transistors (SETs) operating in the Coulomb blockade regime with very low supply voltages. We evaluate the energy - performance tradeoff metrics of such BDD circuits using time domain Monte Carlo simulations and compare them with the energy-optimized CMOS logic circuits. Simulation results show that the proposed approach achieves better energy-delay characteristics than CMOS realizations.

  12. Ultra-Low-Power MEMS Selective Gas Sensors

    NASA Technical Reports Server (NTRS)

    Stetter, Joseph

    2012-01-01

    This innovation is a system for gas sensing that includes an ultra-low-power MEMS (microelectromechanical system) gas sensor, combined with unique electronic circuitry and a proprietary algorithm for operating the sensor. The electronics were created from scratch, and represent a novel design capable of low-power operation of the proprietary MEMS gas sensor platform. The algorithm is used to identify a specific target gas in a gas mixture, making the sensor selective to that target gas.

  13. System and method for magnetic current density imaging at ultra low magnetic fields

    DOEpatents

    Espy, Michelle A.; George, John Stevens; Kraus, Robert Henry; Magnelind, Per; Matlashov, Andrei Nikolaevich; Tucker, Don; Turovets, Sergei; Volegov, Petr Lvovich

    2016-02-09

    Preferred systems can include an electrical impedance tomography apparatus electrically connectable to an object; an ultra low field magnetic resonance imaging apparatus including a plurality of field directions and disposable about the object; a controller connected to the ultra low field magnetic resonance imaging apparatus and configured to implement a sequencing of one or more ultra low magnetic fields substantially along one or more of the plurality of field directions; and a display connected to the controller, and wherein the controller is further configured to reconstruct a displayable image of an electrical current density in the object. Preferred methods, apparatuses, and computer program products are also disclosed.

  14. Combining naltrexone and prazosin in a single oral medication decreases alcohol drinking more effectively than does either drug alone.

    PubMed

    Froehlich, Janice C; Hausauer, Brett J; Rasmussen, Dennis D

    2013-10-01

    Naltrexone (NTX) is underutilized in clinical treatment settings because its efficacy is modest, and it is not effective for all alcoholics and, when it is effective, a significant number of alcoholics fail to maintain initial treatment gains and subsequently relapse to heavy drinking. This has slowed acceptance of NTX by the treatment community, and there is a clear need for additional treatments for alcoholism and alcohol use disorders. Given that NTX and prazosin can each reduce alcohol drinking in rats selectively bred for alcohol preference and high voluntary alcohol drinking (alcohol-preferring "P" rats), we tested whether a combination of NTX + prazosin is more effective in decreasing alcohol drinking than is either drug alone. P rats were given access to a 15% (v/v) alcohol solution for 2 hours daily. Rats were fed NTX and prazosin, alone or in combination, prior to onset of the daily 2-hour alcohol access period for 4 weeks and the effect of drug treatment on alcohol and water intake was assessed. During the first week of treatment, neither a low dose of NTX, nor prazosin, was effective in decreasing alcohol intake when each drug was administered alone, but combining the 2 drugs in a single medication significantly reduced alcohol intake. The combination was as effective as was a higher dose of NTX. Using a low dose of NTX in combination with prazosin may reduce the potential for undesirable side effects early in treatment which, in turn, may improve patient compliance and result in a more successful outcome when NTX is used for treating alcoholism and alcohol use disorders. Combining low-dose NTX and prazosin in a single medication may be more useful than is either drug alone for treating both inpatient and outpatient alcoholics and heavy drinkers early in the treatment process. Copyright © 2013 by the Research Society on Alcoholism.

  15. Noise thermometry at ultra-low temperatures.

    PubMed

    Rothfuss, D; Reiser, A; Fleischmann, A; Enss, C

    2016-03-28

    The options for primary thermometry at ultra-low temperatures are rather limited. In practice, most laboratories are using (195)Pt NMR thermometers in the microkelvin range. In recent years, current sensing direct current superconducting quantum interference devices (DC-SQUIDs) have enabled the use of noise thermometry in this temperature range. Such devices have also demonstrated the potential for primary thermometry. One major advantage of noise thermometry is the fact that no driving current is needed to operate the device and thus the heat dissipation within the thermometer can be reduced to a minimum. Ultimately, the intrinsic power dissipation is given by the negligible back action of the readout SQUID. For thermometry in low-temperature experiments, current noise thermometers and magnetic flux fluctuation thermometers have proved to be most suitable. To make use of such thermometers at ultra-low temperatures, we have developed a cross-correlation technique that reduces the amplifier noise contribution to a negligible value. For this, the magnetic flux fluctuations caused by the Brownian motion of the electrons in our noise source are measured inductively by two DC-SQUID magnetometers simultaneously and the signals from these two channels are cross-correlated. Experimentally, we have characterized a thermometer made of a cold-worked high-purity copper cylinder with a diameter of 5 mm and a length of 20 mm for temperatures between 42 μK and 0.8 K. For a given temperature, a measuring time below 1 min is sufficient to reach a precision of better than 1%. The extremely low power dissipation in the thermometer allows continuous operation without heating effects. © 2016 The Author(s).

  16. Effect of chronic delivery of the Toll-like receptor 4 antagonist (+)-Naltrexone on incubation of heroin craving

    PubMed Central

    Theberge, Florence R.; Li, Xuan; Kambhampati, Sarita; Pickens, Charles L.; St. Laurent, Robyn; Bossert, Jennifer M.; Baumann, Michael H.; Hutchinson, Mark R.; Rice, Kenner C.; Watkins, Linda R.; Shaham, Yavin

    2013-01-01

    Background Recent evidence implicates toll-like receptor 4 (TLR4) in opioid analgesia, tolerance, conditioned place preference, and self-administration. Here we determined the effect of the TLR4 antagonist (+)-naltrexone (a μ-opioid receptor inactive isomer) on the time-dependent increases in cue-induced heroin seeking after withdrawal (incubation of heroin craving). Methods In an initial experiment, we trained rats for 9 h/day to self-administer heroin (0.1 mg/kg/infusion) for 9 days; lever presses were paired with a 5-sec tone-light cue. We then assessed cue-induced heroin seeking in 30-min extinction sessions on withdrawal day 1; immediately after testing, we surgically implanted rats with Alzet minipumps delivering (+)-naltrexone (0, 7.5, 15, 30 mg/kg/day, s.c.) for 14 days. We then tested the rats for incubated cue-induced heroin seeking in 3-h extinction tests on withdrawal day 13. Results We found that chronic delivery of (+)-naltrexone via minipumps during the withdrawal phase decreased incubated cue-induced heroin seeking. In follow-up experiments, we found that acute injections of (+)-naltrexone immediately before withdrawal day 13 extinction test had no effect on incubated cue-induced heroin seeking. Furthermore, chronic delivery of (+)-naltrexone (15 or 30 mg/kg/day) or acute systemic injections (15 or 30 mg/kg) had no effect on ongoing extended access heroin self-administration. Finally, in rats trained to self-administer methamphetamine (0.1 mg/kg/infusion, 9 h/d, 9 days), chronic delivery of (+)-naltrexone (30 mg/kg/day) during the withdrawal phase had no effect on incubated cue-induced methamphetamine seeking. Conclusions The present results suggest a critical role of TLR4 in the development of incubation of heroin, but not methamphetamine, craving. PMID:23384483

  17. Investigating the safety and efficacy of naltrexone for anti-psychotic induced weight gain in severe mental illness: study protocol of a double-blind, randomized, placebo-controlled trial.

    PubMed

    Tek, Cenk; Guloksuz, Sinan; Srihari, Vinod H; Reutenauer, Erin L

    2013-06-27

    Obesity is a growing health problem leading to high rates of mortality and morbidity in patients with severe mental illness (SMI). The increased rate of obesity is largely attributed to antipsychotic use. The effect of antipsychotic medications on H1 and 5HT2 receptors has been associated with weight gain, but there is also a substantial amount of evidence showing that D2 receptor blockade may be responsible for weight gain by interacting with the dopamine-opioid system. Unfortunately, current available medications for weight loss have limited efficacy in this population. Naltrexone, an opioid receptor antagonist, may be a promising agent to reduce antipsychotic induced weight gain by decreasing food cravings. We aim to investigate the safety and efficacy of two doses of naltrexone (25 mg & 50 mg) versus placebo for weight and health risk reduction in overweight and obese individuals (BMI ≥ 28) with SMI, who gained weight while being treated with antipsychotics. One hundred and forty four patients will be recruited throughout the greater New Haven area. The participants will be randomized to naltrexone 25 mg/day, naltrexone 50 mg/day, or placebo in a 1:1:1 ratio. Participants will be on the study medication for 52 weeks, and assessed weekly for the first 4 weeks and bi-weekly thereafter. The primary outcome measurements are weight reduction and percentage achieving clinically significant weight loss (5% of total body weight). Waist circumference, body mass index, serum lipid profile, fasting glucose, and glycosylated hemoglobin are the secondary outcome measures. The effect of naltrexone on other outcome measurements such as schizophrenia symptoms, depression, dietary consumption, quality of life, cognitive functioning, physical activity, metabolism/inflammation markers, serum leptin, ghrelin, peptide YY, adinopectin, high sensitivity CRP, interleukin 6, interleukin-1B, interleukin-18, and tumor necrosis factor alpha (TNF-α) will be evaluated. The data will be

  18. Reduction of conditioned pain modulation in humans by naltrexone: an exploratory study of the effects of pain catastrophizing

    PubMed Central

    Goodin, Burel; Kindler, Lindsay L.; Caudle, Robert M.; Edwards, Robert R.; Gravenstein, Nikolaus; Riley, Joseph L.; Fillingim, Roger B.

    2013-01-01

    The current study tested the hypothesis that conditioned pain modulation is mediated by the release of endogenous opioids with a placebo-controlled (sugar pill) study of naltrexone (50 mg) in 33 healthy volunteers over two counter-balanced sessions. Pain modulation consisted of rating of heat pain (palm) during concurrent cold water immersion (foot). Compared to baseline heat pain ratings, concurrent foot immersion lowered pain intensity ratings, which suggests an inhibitory effect, was reduced with naltrexone, suggesting at least partial dependence of inhibition on endogenous opioids. An exploratory analysis revealed that individual differences in catastrophizing moderated the effects of naltrexone; endogenous opioid blockade abolished modulation in subjects lower in catastrophizing while modulation was unaffected by naltrexone among high catastrophizers. The results suggest a role of endogenous opioids in endogenous analgesia, but hint that multiple systems might contribute to conditioned pain modulation, and that these systems might be differentially activated as a function of individual differences in responses to pain. PMID:22534819

  19. Influence of Ultra-Low-Dose and Iterative Reconstructions on the Visualization of Orbital Soft Tissues on Maxillofacial CT.

    PubMed

    Widmann, G; Juranek, D; Waldenberger, F; Schullian, P; Dennhardt, A; Hoermann, R; Steurer, M; Gassner, E-M; Puelacher, W

    2017-08-01

    Dose reduction on CT scans for surgical planning and postoperative evaluation of midface and orbital fractures is an important concern. The purpose of this study was to evaluate the variability of various low-dose and iterative reconstruction techniques on the visualization of orbital soft tissues. Contrast-to-noise ratios of the optic nerve and inferior rectus muscle and subjective scores of a human cadaver were calculated from CT with a reference dose protocol (CT dose index volume = 36.69 mGy) and a subsequent series of low-dose protocols (LDPs I-4: CT dose index volume = 4.18, 2.64, 0.99, and 0.53 mGy) with filtered back-projection (FBP) and adaptive statistical iterative reconstruction (ASIR)-50, ASIR-100, and model-based iterative reconstruction. The Dunn Multiple Comparison Test was used to compare each combination of protocols (α = .05). Compared with the reference dose protocol with FBP, the following statistically significant differences in contrast-to-noise ratios were shown (all, P ≤ .012) for the following: 1) optic nerve: LDP-I with FBP; LDP-II with FBP and ASIR-50; LDP-III with FBP, ASIR-50, and ASIR-100; and LDP-IV with FBP, ASIR-50, and ASIR-100; and 2) inferior rectus muscle: LDP-II with FBP, LDP-III with FBP and ASIR-50, and LDP-IV with FBP, ASIR-50, and ASIR-100. Model-based iterative reconstruction showed the best contrast-to-noise ratio in all images and provided similar subjective scores for LDP-II. ASIR-50 had no remarkable effect, and ASIR-100, a small effect on subjective scores. Compared with a reference dose protocol with FBP, model-based iterative reconstruction may show similar diagnostic visibility of orbital soft tissues at a CT dose index volume of 2.64 mGy. Low-dose technology and iterative reconstruction technology may redefine current reference dose levels in maxillofacial CT. © 2017 by American Journal of Neuroradiology.

  20. Ultra-Low Noise Germanium Neutrino Detection system (ULGeN).

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cabrera-Palmer, Belkis; Barton, Paul

    Monitoring nuclear power plant operation by measuring the antineutrino flux has become an active research field for safeguards and non-proliferation. We describe various efforts to demonstrate the feasibility of reactor monitoring based on the detection of the Coherent Neutrino Nucleus Scattering (CNNS) process with High Purity Germanium (HPGe) technology. CNNS detection for reactor antineutrino energies requires lowering the electronic noise in low-capacitance kg-scale HPGe detectors below 100 eV as well as stringent reduction in other particle backgrounds. Existing state- of-the-art detectors are limited to an electronic noise of 95 eV-FWHM. In this work, we employed an ultra-low capacitance point-contact detectormore » with a commercial integrated circuit preamplifier- on-a-chip in an ultra-low vibration mechanically cooled cryostat to achieve an electronic noise of 39 eV-FWHM at 43 K. We also present the results of a background measurement campaign at the Spallation Neutron Source to select the area with sufficient low background to allow a successful first-time measurement of the CNNS process.« less

  1. Extended-release naltrexone for pre-release prisoners: A randomized trial of medical mobile treatment

    PubMed Central

    Gordon, Michael S.; Vocci, Frank J.; Fitzgerald, Terrence T.; O'Grady, Kevin E.; O'Brien, Charles P.

    2017-01-01

    Background Extended-release naltrexone (XR-NTX), is an effective treatment for opioid use disorder but is rarely initiated in US prisons or with criminal justice populations. Mobile treatment for chronic diseases have been implemented in a variety of settings. Mobile treatment may provide an opportunity to expand outreach to parolees to surmount barriers to traditional clinic treatment. Methods Male and female prisoners (240) with pre-incarceration histories of opioid use disorder who are within one month of release from prison will be enrolled in this randomized clinical trial. Participants are randomized to one of two study arms: 1) [XR-NTX-OTx] One injection of long-acting naltrexone in prison, followed by 6 monthly injections post-release at a community opioid treatment program; or 2) [XR-NTX+ MMTx] One injection of long-acting naltrexone in prison followed by 6 monthly injections post-release at the patient's place of residence utilizing mobile medical treatment. The primary outcomes are: treatment adherence; opioid use; criminal activity; re-arrest; reincarceration; and HIV risk-behaviors. Results We describe the background and rationale for the study, its aims, hypotheses, and study design. Conclusions The use of long-acting injectable naltrexone may be a promising form of treatment for pre-release prisoners. Finally, as many individuals in the criminal justice system drop out of treatment, this study will assess whether treatment at their place of residence will improve adherence and positively affect treatment outcomes. PMID:28011389

  2. Extended-release naltrexone for pre-release prisoners: A randomized trial of medical mobile treatment.

    PubMed

    Gordon, Michael S; Vocci, Frank J; Fitzgerald, Terrence T; O'Grady, Kevin E; O'Brien, Charles P

    2017-02-01

    Extended-release naltrexone (XR-NTX), is an effective treatment for opioid use disorder but is rarely initiated in US prisons or with criminal justice populations. Mobile treatment for chronic diseases has been implemented in a variety of settings. Mobile treatment may provide an opportunity to expand outreach to parolees to surmount barriers to traditional clinic treatment. Male and female prisoners (240) with pre-incarceration histories of opioid use disorder who are within one month of release from prison will be enrolled in this randomized clinical trial. Participants are randomized to one of two study arms: 1) [XR-NTX-OTx] One injection of long-acting naltrexone in prison, followed by 6 monthly injections post-release at a community opioid treatment program; or 2) [XR-NTX+ MMTx] One injection of long-acting naltrexone in prison followed by 6 monthly injections post-release at the patient's place of residence utilizing mobile medical treatment. The primary outcomes are: treatment adherence; opioid use; criminal activity; re-arrest; reincarceration; and HIV risk-behaviors. We describe the background and rationale for the study, its aims, hypotheses, and study design. The use of long-acting injectable naltrexone may be a promising form of treatment for pre-release prisoners. Finally, as many individuals in the criminal justice system drop out of treatment, this study will assess whether treatment at their place of residence will improve adherence and positively affect treatment outcomes. ClinicalTrials.gov: NCT02867124. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Ultra-low-loss optical fiber nanotapers.

    PubMed

    Brambilla, Gilberto; Finazzi, Vittoria; Richardson, David

    2004-05-17

    Optical fiber tapers with a waist size larger than 1microm are commonplace in telecommunications and sensor applications. However the fabrication of low-loss optical fiber tapers with subwavelength diameters was previously thought to be impractical due to difficulties associated with control of the surface roughness and diameter uniformity. In this paper we show that very-long ultra-low-loss tapers can in fact be produced using a conventional fiber taper rig incorporating a simple burner configuration. For single-mode operation, the optical losses we achieve at 1.55microm are one order of magnitude lower than losses previously reported in the literature for tapers of a similar size. SEM images confirm excellent taper uniformity. We believe that these low-loss structures should pave the way to a whole range of fiber nanodevices.

  4. Effects of naltrexone on electrocutaneous pain in patients with hypertension compared to normotensive individuals

    PubMed Central

    Ring, Christopher; France, Christopher R.; al'Absi, Mustafa; Edwards, Louisa; McIntyre, David; Carroll, Douglas; Martin, Una

    2008-01-01

    An opioid mechanism may help explain hypertensive hypoalgesia. A double-blind placebo-controlled design compared the effects of opioid blockade (naltrexone) and placebo on electrocutaneous pain threshold, pain tolerance, and retrospective McGill Pain Questionnaire ratings in 35 unmedicated patients with essential hypertension and 28 normotensive individuals. The hypertensives experienced less pain than normotensives during the assessment of their pain tolerance; however, this manifestation of hypertensive hypoalgesia was not moderated by naltrexone. These findings fail to support the hypothesis that essential hypertension is characterised by relative opioid insensitivity. PMID:18031920

  5. Ultra-low-cost clinical pulse oximetry.

    PubMed

    Petersen, Christian L; Gan, Heng; MacInnis, Martin J; Dumont, Guy A; Ansermino, J Mark

    2013-01-01

    An ultra-low-cost pulse oximeter is presented that interfaces a conventional clinical finger sensor with a mobile phone through the headset jack audio interface. All signal processing is performed using the audio subsystem of the phone. In a preliminary volunteer study in a hypoxia chamber, we compared the oxygen saturation obtained with the audio pulse oximeter against a commercially available (and FDA approved) reference pulse oximeter (Nonin Xpod). Good agreement was found between the outputs of the two devices.

  6. International Workshop on Neuroimmunomodulation (2nd) Held in Dubrovnik (Yugoslavia) on 1-6 June 1986.

    DTIC Science & Technology

    1986-09-18

    systemically with doses of reaction) were sharply reduced. Histo- naltrexone or naloxone and subsequently logically, the infiltration of the dermis...challenged with a lethal dose of antigen. with polymorphonuclear (Arthus reaction) Both naloxone and naltrexone were found and mononuclear cells (delayed...for Integrative Biomedical Research, Eb- roendocrine cell type present in low num- matingen, Switzerland) reported on the bers in the spleen, lymph

  7. A Retrospective Cohort Study of Obstetric Outcomes in Opioid-Dependent Women Treated with Implant Naltrexone, Oral Methadone or Sublingual Buprenorphine, and Non-Dependent Controls.

    PubMed

    Kelty, Erin; Hulse, Gary

    2017-07-01

    Opioid pharmacotherapies play an important role in the treatment of opioid-dependent women; however, very little is known about the safety of naltrexone in pregnant patients. This study examined the obstetric health of opioid-dependent women who were treated with implant naltrexone during pregnancy, and compared them with women treated with methadone and/or buprenorphine and a cohort of non-opioid-dependent controls. Women treated with implant naltrexone, oral methadone or sublingual buprenorphine between 2001 and 2010, along with a cohort of age-matched controls, were linked with records from midwives, hospital and emergency departments (EDs) and the death registry to identify pregnancy and health events that occurred during pregnancy and in the post-partum period. Overall rates of pregnancy loss (requiring hospital or ED attendance) were significantly elevated in naltrexone-treated women compared with buprenorphine-treated women (p = 0.018) and controls (p < 0.001); however, they were not statistically different to methadone-treated women (p = 0.210). Birth rates in women on naltrexone implant treatment were significantly higher than in all three comparison groups (p < 0.001). Rates of hospital and ED attendance during pregnancy in the naltrexone-treated women were not statistically different to those of either the methadone or buprenorphine groups, and neither were overall complications during pregnancy and labour. Overall rates of complications during pregnancy were significantly higher in the naltrexone-treated women than in the controls. Opioid-dependent women treated with naltrexone implant had higher rates of birth than the other three groups (methadone- or buprenorphine-treated women, or age-matched controls). Overall rates of complications during pregnancy were elevated in naltrexone-treated women when compared with the control group, but were generally not significantly different to rates in methadone- or buprenorphine-treated women.

  8. Using compressive measurement to obtain images at ultra low-light-level

    NASA Astrophysics Data System (ADS)

    Ke, Jun; Wei, Ping

    2013-08-01

    In this paper, a compressive imaging architecture is used for ultra low-light-level imaging. In such a system, features, instead of object pixels, are imaged onto a photocathode, and then magnified by an image intensifier. By doing so, system measurement SNR is increased significantly. Therefore, the new system can image objects at ultra low-ligh-level, while a conventional system has difficulty. PCA projection is used to collect feature measurements in this work. Linear Wiener operator and nonlinear method based on FoE model are used to reconstruct objects. Root mean square error (RMSE) is used to quantify system reconstruction quality.

  9. Ultra-low Temperature Curable Conductive Silver Adhesive with different Resin Matrix

    NASA Astrophysics Data System (ADS)

    Zhou, Xingli; Wang, Likun; Liao, Qingwei; Yan, Chao; Li, Xing; Qin, Lei

    2018-03-01

    The ultra-low temperature curable conductive silver adhesive with curing temperature less than 100 °C needed urgently for the surface conductive treatment of piezoelectric composite material due to the low thermal resistance of composite material and low adhesion strength of adhesive. An ultra-low temperature curable conductive adhesive with high adhesion strength was obtained for the applications of piezoelectric composite material. The microstructure, conductive properties and adhesive properties with different resin matrix were investigated. The conductive adhesive with AG-80 as the resin matrix has the shorter curing time (20min), lower curing temperature (90°C) and higher adhesion strength (7.6MPa). The resistivity of AG-80 sample has the lower value (2.13 × 10-4Ω·cm) than the 618 sample (4.44 × 10-4Ω·cm).

  10. Ultrastructural Study on Ultra-Low Frequency Electromagnetic Fields and Transfer Factor Effects on Skin Ulcers

    NASA Astrophysics Data System (ADS)

    Cadena, M. S. Reyes; Chapul, L. Sánchez; Pérez, Javiér; García, M. N. Jiménez; López, M. A. Jiménez; Espíndola, M. E. Sánchez; Perez, R. Paniagua; Hernández, N. A.; Paniagua, G.; Uribe, F.; Nava, J. J. Godina; Segura, M. A. Rodríguez

    2008-08-01

    We determined the effect of 120Hz ultra low frequency electromagnetic field (ELF) on the healing process of skin in 20 Wistar rats distributed in four groups in which chronic dermal ulcers had been produced. The first two groups received a dose of the transfer factor and interferon-beta (IFN-β) every 24 h during 12 days. The third group (positive control) received only electromagnetic field (ELF) sessions, and in the fourth group (negative control), no treatment was applied. The electromagnetic field was applied through a Helmholtz coils; 30 Gauss of intensity. Results shown histological changes that improve the healing process in animals subjected to ELF together with the transfer factor.

  11. Aversion to injection limits acceptability of extended-release naltrexone among homeless, alcohol-dependent patients.

    PubMed

    Friedmann, Peter D; Mello, Dawn; Lonergan, Sean; Bourgault, Claire; O'Toole, Thomas P

    2013-01-01

    Ending homelessness is a major priority of the Department of Veteran Affairs (VA), and alcohol use can be a barrier to stable housing. Clinical trials suggest that depot extended-release naltrexone (XR-NTX) is efficacious in reducing alcohol consumption among alcohol-dependent subjects. An open-label, randomized pilot study sought to examine the feasibility and effectiveness of XR-NTX versus oral naltrexone to improve alcohol consumption and housing stability among homeless, alcohol-dependent veterans at the Providence Veteran Affairs Medical Center. Of 215 potential candidates approached over a 16-month recruitment period, only 15 agreed to consider study entry and 7 were randomized. The primary reasons given for refusal were not wanting an injection; fear of needles; and not wanting to change drinking habits. Only 1 participant in the XR-NTX group returned after the first injection. Three participants in the oral naltrexone group attended all 7 visits and had good outcomes. Although XR-NTX has demonstrated efficacy in reducing heavy drinking, limited acceptance of the injection might reduce its effectiveness among homeless, alcohol-dependent patients.

  12. Feasibility study of SiGHT: a novel ultra low background photosensor for low temperature operation

    DOE PAGES

    Wang, Y.; Fan, A.; Fiorillo, G.; ...

    2017-02-27

    Rare event search experiments, such as those searching for dark matter and observations of neutrinoless double beta decay, require ultra low levels of radioactive background for unmistakable identification. In order to reduce the radioactive background of detectors used in these types of event searches, low background photosensors are required, as the physical size of these detectors become increasing larger, and hence the number of such photosensors used also increases rapidly. Considering that most dark matter and neutrinoless double beta decay experiments are turning towards using noble liquids as the target choice, liquid xenon and liquid argon for instance, photosensors thatmore » can work well at cryogenic temperatures are required, 165 K and 87 K for liquid xenon and liquid argon, respectively. The Silicon Geiger Hybrid Tube (SiGHT) is a novel photosensor designed specifically for use in ultra low background experiments operating at cryogenic temperatures. It is based on the proven photocathode plus silicon photomultiplier (SiPM) hybrid technology and consists of very few other, but also ultra radio-pure, materials like fused silica and silicon for the SiPM. Lastly, the introduction of the SiGHT concept, as well as a feasibility study for its production, is reported in this article.« less

  13. Advanced Computational Approaches for Characterizing Stochastic Cellular Responses to Low Dose, Low Dose Rate Exposures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Scott, Bobby, R., Ph.D.

    2003-06-27

    OAK - B135 This project final report summarizes modeling research conducted in the U.S. Department of Energy (DOE), Low Dose Radiation Research Program at the Lovelace Respiratory Research Institute from October 1998 through June 2003. The modeling research described involves critically evaluating the validity of the linear nonthreshold (LNT) risk model as it relates to stochastic effects induced in cells by low doses of ionizing radiation and genotoxic chemicals. The LNT model plays a central role in low-dose risk assessment for humans. With the LNT model, any radiation (or genotoxic chemical) exposure is assumed to increase one¡¯s risk of cancer.more » Based on the LNT model, others have predicted tens of thousands of cancer deaths related to environmental exposure to radioactive material from nuclear accidents (e.g., Chernobyl) and fallout from nuclear weapons testing. Our research has focused on developing biologically based models that explain the shape of dose-response curves for low-dose radiation and genotoxic chemical-induced stochastic effects in cells. Understanding the shape of the dose-response curve for radiation and genotoxic chemical-induced stochastic effects in cells helps to better understand the shape of the dose-response curve for cancer induction in humans. We have used a modeling approach that facilitated model revisions over time, allowing for timely incorporation of new knowledge gained related to the biological basis for low-dose-induced stochastic effects in cells. Both deleterious (e.g., genomic instability, mutations, and neoplastic transformation) and protective (e.g., DNA repair and apoptosis) effects have been included in our modeling. Our most advanced model, NEOTRANS2, involves differing levels of genomic instability. Persistent genomic instability is presumed to be associated with nonspecific, nonlethal mutations and to increase both the risk for neoplastic transformation and for cancer occurrence. Our research results, based

  14. A programmable ultra-low noise X-band exciter.

    PubMed

    MacMullen, A; Hoover, L R; Justice, R D; Callahan, B S

    2001-07-01

    A programmable ultra-low noise X-band exciter has been developed using commercial off-the-shelf components. Its phase noise is more than 10 dB below the best available microwave synthesizers. It covers a 7% frequency band with 0.1-Hz resolution. The X-band output at +23 dBm is a combination of signals from an X-band sapphire-loaded cavity oscillator (SLCO), a low noise UHF frequency synthesizer, and special-purpose frequency translation and up-conversion circuitry.

  15. Development of a Low cost Ultra tiny Line Laser Range Sensor

    DTIC Science & Technology

    2016-12-01

    Development of a Low-cost Ultra-tiny Line Laser Range Sensor Xiangyu Chen∗, Moju Zhao∗, Lingzhu Xiang†, Fumihito Sugai∗, Hiroaki Yaguchi∗, Kei Okada...and Masayuki Inaba∗ Abstract— To enable robotic sensing for tasks with require- ments on weight, size, and cost, we develop an ultra-tiny line laser ...view customizable using different laser lenses. The optimal measurement range of the sensor is 0.05[m] ∼ 2[m]. Higher sampling rates can be achieved

  16. Ultra-low field nuclear magnetic resonance and magnetic resonance imaging to discriminate and identify materials

    DOEpatents

    Kraus, Robert H.; Matlashov, Andrei N.; Espy, Michelle A.; Volegov, Petr L.

    2010-03-30

    An ultra-low magnetic field NMR system can non-invasively examine containers. Database matching techniques can then identify hazardous materials within the containers. Ultra-low field NMR systems are ideal for this purpose because they do not require large powerful magnets and because they can examine materials enclosed in conductive shells such as lead shells. The NMR examination technique can be combined with ultra-low field NMR imaging, where an NMR image is obtained and analyzed to identify target volumes. Spatial sensitivity encoding can also be used to identify target volumes. After the target volumes are identified the NMR measurement technique can be used to identify their contents.

  17. Injectable and implantable sustained release naltrexone in the treatment of opioid addiction

    PubMed Central

    Kunøe, Nikolaj; Lobmaier, Philipp; Ngo, Hanh; Hulse, Gary

    2014-01-01

    Sustained release technologies for administering the opioid antagonist naltrexone (SRX) have the potential to assist opioid-addicted patients in their efforts to maintain abstinence from heroin and other opioid agonists. Recently, reliable SRX formulations in intramuscular or implantable polymers that release naltrexone for 1–7 months have become available for clinical use and research. This qualitative review of the literature provides an overview of the technologies currently available for SRX and their effectiveness in reducing opioid use and other relevant outcomes. The majority of studies indicate that SRX is effective in reducing heroin use, and the most frequently studied SRX formulations have acceptable adverse events profiles. Registry data indicate a protective effect of SRX on mortality and morbidity. In some studies, SRX also seems to affect other outcomes, such as concomitant substance use, vocational training attendance, needle use, and risk behaviour for blood-borne diseases such as hepatitis or human immunodeficiency virus. There is a general need for more controlled studies, in particular to compare SRX with agonist maintenance treatment, to study combinations of SRX with behavioural interventions, and to study at-risk groups such as prison inmates or opioid-addicted pregnant patients. The literature suggests that sustained release naltrexone is a feasible, safe and effective option for assisting abstinence efforts in opioid addiction. PMID:23088328

  18. Injectable and implantable sustained release naltrexone in the treatment of opioid addiction.

    PubMed

    Kunøe, Nikolaj; Lobmaier, Philipp; Ngo, Hanh; Hulse, Gary

    2014-02-01

    Sustained release technologies for administering the opioid antagonist naltrexone (SRX) have the potential to assist opioid-addicted patients in their efforts to maintain abstinence from heroin and other opioid agonists. Recently, reliable SRX formulations in intramuscular or implantable polymers that release naltrexone for 1-7 months have become available for clinical use and research. This qualitative review of the literature provides an overview of the technologies currently available for SRX and their effectiveness in reducing opioid use and other relevant outcomes. The majority of studies indicate that SRX is effective in reducing heroin use, and the most frequently studied SRX formulations have acceptable adverse events profiles. Registry data indicate a protective effect of SRX on mortality and morbidity. In some studies, SRX also seems to affect other outcomes, such as concomitant substance use, vocational training attendance, needle use, and risk behaviour for blood-borne diseases such as hepatitis or human immunodeficiency virus. There is a general need for more controlled studies, in particular to compare SRX with agonist maintenance treatment, to study combinations of SRX with behavioural interventions, and to study at-risk groups such as prison inmates or opioid-addicted pregnant patients. The literature suggests that sustained release naltrexone is a feasible, safe and effective option for assisting abstinence efforts in opioid addiction. © 2012 The Authors. British Journal of Clinical Pharmacology © 2012 The British Pharmacological Society.

  19. Optimizing Parameters of Axial Pressure-Compounded Ultra-Low Power Impulse Turbines at Preliminary Design

    NASA Astrophysics Data System (ADS)

    Kalabukhov, D. S.; Radko, V. M.; Grigoriev, V. A.

    2018-01-01

    Ultra-low power turbine drives are used as energy sources in auxiliary power systems, energy units, terrestrial, marine, air and space transport within the confines of shaft power N td = 0.01…10 kW. In this paper we propose a new approach to the development of surrogate models for evaluating the integrated efficiency of multistage ultra-low power impulse turbine with pressure stages. This method is based on the use of existing mathematical models of ultra-low power turbine stage efficiency and mass. It has been used in a method for selecting the rational parameters of two-stage axial ultra-low power turbine. The article describes the basic features of an algorithm for two-stage turbine parameters optimization and for efficiency criteria evaluating. Pledged mathematical models are intended for use at the preliminary design of turbine drive. The optimization method was tested at preliminary design of an air starter turbine. Validation was carried out by comparing the results of optimization calculations and numerical gas-dynamic simulation in the Ansys CFX package. The results indicate a sufficient accuracy of used surrogate models for axial two-stage turbine parameters selection

  20. CMOS Ultra Low Power Radiation Tolerant (CULPRiT) Microelectronics

    NASA Technical Reports Server (NTRS)

    Yeh, Penshu; Maki, Gary

    2007-01-01

    Space Electronics needs Radiation Tolerance or hardness to withstand the harsh space environment: high-energy particles can change the state of the electronics or puncture transistors making them disfunctional. This viewgraph document reviews the use of CMOS Ultra Low Power Radiation Tolerant circuits for NASA's electronic requirements.

  1. Ultrastructural Study on Ultra-Low Frequency Electromagnetic Fields and Transfer Factor Effects on Skin Ulcers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cadena, M. S. Reyes; Chapul, L. Sanchez; Perez, Javier

    2008-08-11

    We determined the effect of 120Hz ultra low frequency electromagnetic field (ELF) on the healing process of skin in 20 Wistar rats distributed in four groups in which chronic dermal ulcers had been produced. The first two groups received a dose of the transfer factor and interferon-beta (IFN-{beta}) every 24 h during 12 days. The third group (positive control) received only electromagnetic field (ELF) sessions, and in the fourth group (negative control), no treatment was applied. The electromagnetic field was applied through a Helmholtz coils; 30 Gauss of intensity. Results shown histological changes that improve the healing process in animalsmore » subjected to ELF together with the transfer factor.« less

  2. Controlling Low-Rate Signal Path Microdischarge for an Ultra-Low-Background Proportional Counter

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mace, Emily K.; Aalseth, Craig E.; Bonicalzi, Ricco

    2013-05-01

    ABSTRACT Pacific Northwest National Laboratory (PNNL) has developed an ultra-low-background proportional counter (ULBPC) made of high purity copper. These detectors are part of an ultra-low-background counting system (ULBCS) in the newly constructed shallow underground laboratory at PNNL (at a depth of ~30 meters water-equivalent). To control backgrounds, the current preamplifier electronics are located outside the ULBCS shielding. Thus the signal from the detector travels through ~1 meter of cable and is potentially susceptible to high voltage microdischarge and other sources of electronic noise. Based on initial successful tests, commercial cables and connectors were used for this critical signal path. Subsequentmore » testing across different batches of commercial cables and connectors, however, showed unwanted (but still low) rates of microdischarge noise. To control this noise source, two approaches were pursued: first, to carefully validate cables, connectors, and other commercial components in this critical signal path, making modifications where necessary; second, to develop a custom low-noise, low-background preamplifier that can be integrated with the ULBPC and thus remove most commercial components from the critical signal path. This integrated preamplifier approach is based on the Amptek A250 low-noise charge-integrating preamplifier module. The initial microdischarge signals observed are presented and characterized according to the suspected source. Each of the approaches for mitigation is described, and the results from both are compared with each other and with the original performance seen with commercial cables and connectors.« less

  3. Naltrexone and Bupropion Combination Treatment for Smoking Cessation and Weight Loss in Patients With Schizophrenia.

    PubMed

    Lyu, Xuechan; Du, Jiang; Zhan, Guilai; Wu, Yujie; Su, Hang; Zhu, Youwei; Jarskog, Fredrik; Zhao, Min; Fan, Xiaoduo

    2018-01-01

    Objective: The rates of obesity and cigarette smoking are much higher in patients with schizophrenia compared to the general population. This study was to examine whether naltrexone and bupropion combination treatment can help weight loss and smoking cessation in patients with schizophrenia. Methods: Obese male schizophrenia patients with current cigarette smoking were randomized to receive adjunctive naltrexone (25 mg/day) and bupropion (300 mg/day) combination or placebo for 24 weeks. Twenty-two patients were enrolled in the study, and 21 patients completed the study (11 in the treatment group, and 10 in the placebo group). Body weight, body mass index (BMI), fasting lipids, smoking urge, expired carbon monoxide (CO) level and cigarettes smoked per week were measured at baseline and week 24. Results: There was no significant difference between two groups in changes in weight, BMI, fasting lipids, or cigarette smoking measures ( p 's > 0.05) Conclusion: Naltrexone and bupropion combination treatment didn't show weight loss or smoking cessation effect in patients with schizophrenia in this pilot study.Implications for future studies were discussed. ClinicalTrials.gov identifier: NCT02736474.

  4. Naltrexone and Bupropion Combination Treatment for Smoking Cessation and Weight Loss in Patients With Schizophrenia

    PubMed Central

    Lyu, Xuechan; Du, Jiang; Zhan, Guilai; Wu, Yujie; Su, Hang; Zhu, Youwei; Jarskog, Fredrik; Zhao, Min; Fan, Xiaoduo

    2018-01-01

    Objective: The rates of obesity and cigarette smoking are much higher in patients with schizophrenia compared to the general population. This study was to examine whether naltrexone and bupropion combination treatment can help weight loss and smoking cessation in patients with schizophrenia. Methods: Obese male schizophrenia patients with current cigarette smoking were randomized to receive adjunctive naltrexone (25 mg/day) and bupropion (300 mg/day) combination or placebo for 24 weeks. Twenty-two patients were enrolled in the study, and 21 patients completed the study (11 in the treatment group, and 10 in the placebo group). Body weight, body mass index (BMI), fasting lipids, smoking urge, expired carbon monoxide (CO) level and cigarettes smoked per week were measured at baseline and week 24. Results: There was no significant difference between two groups in changes in weight, BMI, fasting lipids, or cigarette smoking measures (p's > 0.05) Conclusion: Naltrexone and bupropion combination treatment didn't show weight loss or smoking cessation effect in patients with schizophrenia in this pilot study.Implications for future studies were discussed. ClinicalTrials.gov identifier: NCT02736474. PMID:29563871

  5. Ultra-Low Density Organic-Inorganic Composite Materials Possessing Thermally Insulating and Acoustic Damping Properties

    DTIC Science & Technology

    1992-05-07

    Officer. Dr. Kenneth Wynne d. Brief Description of Project- We are investigating the design and synthesis of strong, ultra-low density xerogel and aerogel ...materials of this type would have applications in a broad range of areas including lightweight engine components, high temperature coatings, aircraft wings...we plan to investigate the formation of ultra-low density composites using supercritical universal drying (SCUD) techniques. SiO2 aerogel materials

  6. Ultra Low Dose Delta 9-Tetrahydrocannabinol Protects Mouse Liver from Ischemia Reperfusion Injury.

    PubMed

    Hochhauser, Edith; Lahat, Eylon; Sultan, Maya; Pappo, Orit; Waldman, Maayan; Sarne, Yosef; Shainberg, Asher; Gutman, Mordechai; Safran, Michal; Ben Ari, Ziv

    2015-01-01

    Ischemia/reperfusion (I/R) injury is the main cause of both primary graft dysfunction and primary non-function of liver allografts. Cannabinoids has been reported to attenuate myocardial, cerebral and hepatic I/R oxidative injury. Delta-9-tetrahydrocannabinol (THC), a cannabinoid agonist, is the active components of marijuana. In this study we examined the role of ultralow dose THC (0.002mg/kg) in the protection of livers from I/R injury. This extremely low dose of THC was previously found by us to protect the mice brain and heart from a variety of insults. C57Bl Mice were studied in in vivo model of hepatic segmental (70%) ischemia for 60min followed by reperfusion for 6 hours. THC administration 2h prior to the induction of hepatic I/R was associated with significant attenuated elevations of: serum liver transaminases ALT and AST, the hepatic oxidative stress (activation of the intracellular signaling CREB pathway), the acute proinflammatory response (TNF-α, IL-1α, IL-10 and c-FOS hepatic mRNA levels, and ERK signaling pathway activation). This was followed by cell death (the cleavage of the pro-apoptotic caspase 3, DNA fragmentation and TUNEL) after 6 hours of reperfusion. Significantly less hepatic injury was detected in the THC treated I/R mice and fewer apoptotic hepatocytes cells were identified by morphological criteria compared with untreated mice. A single ultralow dose THC can reduce the apoptotic, oxidative and inflammatory injury induced by hepatic I/R injury. THC may serve as a potential target for therapeutic intervention in hepatic I/R injury during liver transplantation, liver resection and trauma. © 2015 S. Karger AG, Basel.

  7. Sustained-release bupropion versus naltrexone in the treatment of pathological gambling: a preliminary blind-rater study.

    PubMed

    Dannon, Pinhas N; Lowengrub, Katherine; Musin, Ernest; Gonopolski, Yehudit; Kotler, Moshe

    2005-12-01

    Pathological gambling (PG) is a relatively common and highly disabling impulse control disorder. A range of psychotherapeutic agents, including selective serotonin reuptake inhibitors, mood stabilizers, and opioid antagonists, has been shown to be effective in the treatment of PG. The use of selective serotonin reuptake inhibitors and opioid antagonists for PG is consistent with the observation that PG shares features of both the obsessive-compulsive spectrum disorders and addictive disorders. The aim of the study is to compare the effectiveness of sustained-release bupropion versus naltrexone in the treatment of PG. Thirty-six male pathological gamblers were enrolled in our study. A comprehensive psychiatric diagnostic evaluation was performed at baseline on all patients, and patients were screened for symptoms of gambling, depression, and anxiety using the South Oaks Gambling Screen, the Hamilton Depression Rating Scale, the Hamilton Anxiety Rating Scale, and the Clinical Global Impression-Severity Scale. In addition, the patients completed self-report questionnaires about their demographic status. Patients were randomized in 2 groups and received either naltrexone (n = 19) or sustained-release bupropion (n = 17) for 12 weeks in a parallel fashion. Treatment response was monitored using the Clinical Global Impression-Improvement Scale which was performed at weeks 2, 4, 8, and 12. Patients were also assessed for the presence of gambling behavior via an unstructured interview, which was also performed at weeks 2, 4, 6, 8, and 12. Raters were blind to the study treatment. The majority of patients responded well to the drug treatment. Twelve of 17 patients in the sustained-release bupropion group completed the 12-week study, and 13 of 19 naltrexone patients completed the study. Nine (75%) of the 12 completers were rated as full responders in the sustained-release bupropion group versus 10 (76%) of 12 in the naltrexone group. Three (25%) of 12 completers in the

  8. Study on Structural and Dielectric Properties of Ultra-Low-Fire Integratable Dielectric Film for High-Frequency and Microwave Application

    NASA Astrophysics Data System (ADS)

    Qu, Sheng; Zhang, Jihua; Wu, Kaituo; Wang, Lei; Chen, Hongwei

    2018-03-01

    In this study, ultra-low-fire ceramic composites of Zn2Te3O8-30 wt.%TiTe3O8 (ZTT) were prepared by a solid-state reaction method. Densified at 600°C, the best microwave dielectric properties at 8.5 GHz were measured with the ɛ r , tan δ, Q × f, and τ f as 25.6, 1.5 × 10-4, 56191 GHz and 1.66 ppm/°C, respectively. Thin films of ultra-low-fire ZTT were prepared by a radio-frequency magnetron sputtering method. ZTT films which deposited on Au/NiCr/SiO2/Si (100) substrates at 200°C showed good adhesion. From ultra-low-fire ceramic to ultra-low-fire ZTT thin films, the latter maintained all the good high-frequency dielectric properties of the former: high dielectric constant ( ɛ r ˜ 25) and low dissipation factor (tan δ < 5×10-3), low leakage current density (˜ 10-9 A/cm2) and ultra low processing temperature. These excellent properties of the ultra-low-fire ZTT thin film make it possible to be integrated in MMIC and be applied in the research of GaN and GaAs MOSFET devices.

  9. Energy deposition evaluation for ultra-low energy electron beam irradiation systems using calibrated thin radiochromic film and Monte Carlo simulations.

    PubMed

    Matsui, S; Mori, Y; Nonaka, T; Hattori, T; Kasamatsu, Y; Haraguchi, D; Watanabe, Y; Uchiyama, K; Ishikawa, M

    2016-05-01

    For evaluation of on-site dosimetry and process design in industrial use of ultra-low energy electron beam (ULEB) processes, we evaluate the energy deposition using a thin radiochromic film and a Monte Carlo simulation. The response of film dosimeter was calibrated using a high energy electron beam with an acceleration voltage of 2 MV and alanine dosimeters with uncertainty of 11% at coverage factor 2. Using this response function, the results of absorbed dose measurements for ULEB were evaluated from 10 kGy to 100 kGy as a relative dose. The deviation between the responses of deposit energy on the films and Monte Carlo simulations was within 15%. As far as this limitation, relative dose estimation using thin film dosimeters with response function obtained by high energy electron irradiation and simulation results is effective for ULEB irradiation processes management.

  10. Sucrose and naltrexone prevent increased pain sensitivity and impaired long-term memory induced by repetitive neonatal noxious stimulation: Role of BDNF and β-endorphin.

    PubMed

    Nuseir, Khawla Q; Alzoubi, Karem H; Alhusban, Ahmed; Bawaane, Areej; Al-Azzani, Mohammed; Khabour, Omar F

    2017-10-01

    Pain in neonates is associated with short and long-term adverse outcomes. Data demonstrated that long-term consequences of untreated pain are linked to the plasticity of the neonate's brain. Sucrose is effective and safe for reducing painful procedures from single events. However, the mechanism of sucrose-induced analgesia is not fully understood. The role of the opioid system in this analgesia using the opioid receptor antagonist Naltrexone was investigated, plus the long-term effects on learning and memory formation during adulthood. Pain was induced in rat pups via needle pricks of the paws. Sucrose solution and/or naltrexone were administered before the pricks. All treatments started on day one of birth and continued for two weeks. At the end of 8weeks, behavioral studies were conducted to test spatial learning and memory using radial arm water maze (RAWM), and pain threshold via foot-withdrawal response to a hot plate. The hippocampus was dissected; levels of brain derived neurotrophic factor (BDNF) and endorphins were assessed using ELISA. Acute repetitive neonatal pain increased pain sensitivity later in life, while naltrexone with sucrose decreased pain sensitivity. Naltrexone and/or sucrose prevented neonatal pain induced impairment of long-term memory, while neonatal pain decreased levels of BDNF in the hippocampus; this decrease was averted by sucrose and naltrexone. Sucrose with naltrexone significantly increased β-endorphin levels in noxiously stimulated rats. In conclusion, naltrexone and sucrose can reverse increased pain sensitivity and impaired long-term memory induced by acute repetitive neonatal pain probably by normalizing BDNF expression and increasing β-endorphin levels. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Continuous delivery of naltrexone and nalmefene leads to tolerance in reducing alcohol drinking and to supersensitivity of brain opioid receptors.

    PubMed

    Korpi, Esa R; Linden, Anni-Maija; Hytönen, Heidi R; Paasikoski, Nelli; Vashchinkina, Elena; Dudek, Mateusz; Herr, Deron R; Hyytiä, Petri

    2017-07-01

    Opioid antagonist treatments reduce alcohol drinking in rodent models and in alcohol-dependent patients, with variable efficacy across different studies. These treatments may suffer from the development of tolerance and opioid receptor supersensitivity, as suggested by preclinical models showing activation of these processes during and after subchronic high-dose administration of the short-acting opioid antagonist naloxone. In the present study, we compared equipotent low and moderate daily doses of naltrexone and nalmefene, two opioid antagonists in the clinical practice for treatment of alcoholism. The antagonists were given here subcutaneously for 7 days either as daily injections or continuous osmotic minipump-driven infusions to alcohol-preferring AA rats having trained to drink 10% alcohol in a limited access protocol. One day after stopping the antagonist treatment, [ 35 S]GTPγS autoradiography on brain cryostat sections was carried out to examine the coupling of receptors to G protein activation. The results prove the efficacy of repeated injections over infused opioid antagonists in reducing alcohol drinking. Tolerance to the reducing effect on alcohol drinking and to the enhancement of G protein coupling to μ-opioid receptors in various brain regions were consistently detected only after infused antagonists. Supersensitivity of κ-opioid receptors was seen in the ventral and dorsal striatal regions especially by infused nalmefene. Nalmefene showed no clear agonistic activity in rat brain sections or at human recombinant κ-opioid receptors. The findings support the as-needed dosing practice, rather than the standard continual dosing, in the treatment of alcoholism with opioid receptor antagonists. © 2016 Society for the Study of Addiction.

  12. EVALUATING AND DESIGNING ULTRA-LOW-COST SOLAR WATER HEATING SYSTEMS

    EPA Science Inventory

    This project will have three key outputs:

    1. an evaluation of the thermal performance of ultra-low-cost solar components, with components being characterized by their absorbed solar energy per cost;
    2. a built demonstration prototype of...

    3. Ultra Low Temperature Instrumentation for Measurements in Astrophysics : ULTIMA

      DOE Office of Scientific and Technical Information (OSTI.GOV)

      Bunkov, Yu. M.; Elbs, J.; Godfrin, H.

      2006-09-07

      This paper reviews recent advances in particle detection using superfluid 3He at ultra-low temperature about 100 {mu}K, for application in large detector project ULTIMA for the search of non-baryonic Dark Matter. The unique advantages of 3He, and in particular of its superfluid state, for Dark Matter search are highlighted.

    4. Hormones and Endocrine-Disrupting Chemicals: Low-Dose Effects and Nonmonotonic Dose Responses

      PubMed Central

      Colborn, Theo; Hayes, Tyrone B.; Heindel, Jerrold J.; Jacobs, David R.; Lee, Duk-Hee; Shioda, Toshi; Soto, Ana M.; vom Saal, Frederick S.; Welshons, Wade V.; Zoeller, R. Thomas

      2012-01-01

      For decades, studies of endocrine-disrupting chemicals (EDCs) have challenged traditional concepts in toxicology, in particular the dogma of “the dose makes the poison,” because EDCs can have effects at low doses that are not predicted by effects at higher doses. Here, we review two major concepts in EDC studies: low dose and nonmonotonicity. Low-dose effects were defined by the National Toxicology Program as those that occur in the range of human exposures or effects observed at doses below those used for traditional toxicological studies. We review the mechanistic data for low-dose effects and use a weight-of-evidence approach to analyze five examples from the EDC literature. Additionally, we explore nonmonotonic dose-response curves, defined as a nonlinear relationship between dose and effect where the slope of the curve changes sign somewhere within the range of doses examined. We provide a detailed discussion of the mechanisms responsible for generating these phenomena, plus hundreds of examples from the cell culture, animal, and epidemiology literature. We illustrate that nonmonotonic responses and low-dose effects are remarkably common in studies of natural hormones and EDCs. Whether low doses of EDCs influence certain human disorders is no longer conjecture, because epidemiological studies show that environmental exposures to EDCs are associated with human diseases and disabilities. We conclude that when nonmonotonic dose-response curves occur, the effects of low doses cannot be predicted by the effects observed at high doses. Thus, fundamental changes in chemical testing and safety determination are needed to protect human health. PMID:22419778

    5. Naltrexone/bupropion for the treatment of obesity and obesity with Type 2 diabetes.

      PubMed

      Apovian, Caroline M

      2016-03-01

      Contrave(®) is a combination of naltrexone hydrochloride extended release and bupropion hydrochloride extended release for the treatment of obesity, and is used with lifestyle modification. Its safety and efficacy were assessed in four randomized, double-blind, placebo-controlled, 56-week Phase III clinical trials in 4536 adult subjects: COR-1, COR-II, COR-BMOD and COR-DM. All four studies demonstrated statistically significant and clinically meaningful weight loss following up to 52 weeks of treatment with naltrexone/bupropion compared with placebo. The average weight loss from baseline across the four studies was approximately 11-22 lbs (5-9 kg). Results show the efficacy of Contrave for weight loss, as well as significant improvements in cardiometabolic markers. This review focuses on the four studies, their outcomes and the mechanism of action of Contrave.

    6. Enhanced sensitivity to naltrexone-induced drinking suppression of fluid intake and sucrose consumption in maternally separated rats.

      PubMed

      Michaels, Clifford C; Holtzman, Stephen G

      2007-04-01

      Early-life stress has been identified as a risk factor in the development of a host of disorders, including substance abuse; however the link between early postnatal stress and changes in measures of reward has not been thoroughly researched. The current study had two main objectives: 1) to determine the impact of maternal separation (an animal model of early-life stress) on the consumption of 10% and 2.5% sucrose solutions by Long-Evans rat dams and male and female offspring, and 2) to determine the effect of the opioid antagonist naltrexone (0.1-3.0 mg/kg) on drinking by each of those groups. Dam-pup separations occurred for varying lengths of time during the first two postnatal weeks. In Experiment 1, a two-bottle choice test (sucrose solution vs. water) was administered across five days to both nonhandled (NH) and maternally-separated (MS) offspring as adults and to dams 2-4 weeks post-weaning. In Experiment 2, naltrexone was administered prior to two-bottle choice tests. MS males and the dams of MS litters exhibited increased intake of total fluid and sucrose solutions, whereas results from females were less consistent. Naltrexone elicited a greater decrease in fluid intake and sucrose intake in male MS offspring compared to male NH offspring. These results indicate that early postnatal stress alters both sucrose consumption, a non-drug measure of reward, and apparently the brain opioid systems that mediate naltrexone-induced drinking suppression.

    7. A randomized double-blind, placebo-controlled efficacy and safety study of ALO-02 (extended-release oxycodone surrounding sequestered naltrexone) for moderate-to-severe chronic low back pain treatment.

      PubMed

      Rauck, Richard L; Hale, Martin E; Bass, Almasa; Bramson, Candace; Pixton, Glenn; Wilson, Jacquelyn G; Setnik, Beatrice; Meisner, Paul; Sommerville, Kenneth W; Malhotra, Bimal K; Wolfram, Gernot

      2015-09-01

      The objective of this multicenter, double-blind, placebo-controlled, randomized withdrawal study was to evaluate the efficacy and safety of ALO-02, an abuse-deterrent formulation containing pellets of extended-release oxycodone hydrochloride (HCl) surrounding sequestered naltrexone HCl, compared with placebo in the treatment of moderate-to-severe chronic low back pain. An open-label titration period in which all patients received ALO-02 was followed by a double-blind treatment period where patients meeting treatment response criteria were randomized to either a fixed dose of ALO-02 or placebo. Daily average low back pain was assessed using an 11-point numeric rating scale (NRS)-Pain. Of the 663 patients screened, 410 received ALO-02 during the open-label conversion and titration period and 281 patients were randomized to the double-blind treatment period (n = 134, placebo; n = 147, ALO-02). Change in the mean NRS-Pain score from randomization baseline to the final 2 weeks of the treatment period was significantly different favoring ALO-02 compared with placebo (P = 0.0114). Forty-four percent of patients treated with placebo and 57.5% of patients treated with ALO-02 reported ≥30% improvement in weekly average NRS-Pain scores from screening to the final 2 weeks of the treatment period (P = 0.0248). In the double-blind treatment period, 56.8% of patients in the ALO-02 group and 56.0% of patients in the placebo group experienced a treatment-emergent adverse event (TEAE). The most common treatment-related TEAEs for ALO-02 during the treatment period were nausea, vomiting, and constipation, consistent with opioid therapy. ALO-02 has been demonstrated to provide significant reduction of pain in patients with chronic low back pain and has a safety profile similar to other opioids.

    8. Naltrexone moderates the relationship between cue-induced craving and subjective response to methamphetamine in individuals with methamphetamine use disorder.

      PubMed

      Roche, Daniel J O; Worley, Matthew J; Courtney, Kelly E; Bujarski, Spencer; London, Edythe D; Shoptaw, Steven; Ray, Lara A

      2017-07-01

      Reductions in cue-induced craving and subjective response to drugs of abuse are commonly used as initial outcome measures when testing novel medications for the treatment of addiction. Yet neither the relationship between these two measures at the individual level nor the moderating effects of pharmacotherapies on this relationship has been examined. This secondary data analysis sought to examine (1) the predictive relationship between cue-induced craving and subsequent acute subjective response to methamphetamine (MA) and (2) whether the opioid-receptor antagonist naltrexone moderated this association in a sample of non-treatment-seeking individuals who met DSM-IV criteria for MA use disorder (abuse or dependence). Participants (n = 30) completed two 4-day medication regimens (oral naltrexone 50 mg or placebo, in a randomized, counterbalanced, and double-blind fashion). On day 4 of each medication regimen, participants completed a cue-reactivity paradigm followed by intravenous MA administration. Methamphetamine craving was assessed after the cue-reactivity paradigm, and subjective response to MA was assessed during MA infusion. Cue-induced craving for MA was positively associated with post-infusion subjective MA effects, including positive (i.e., stimulation, good effects, feel drug, high), negative (i.e., anxious and depressed), and craving-related (i.e., want more, would like access to drug, crave) responses. Naltrexone, vs. placebo, significantly reduced the association between cue-induced craving and positive subjective response to MA. The findings indicate that naltrexone moderates the predictive relationship between cue-induced craving and positive subjective effects of MA, thereby suggesting a behavioral mechanism by which naltrexone may be efficacious in treating MA use disorder.

    9. Predictors of dropout in an outpatient treatment for problem drinkers including cognitive-behavioral therapy and the opioid antagonist naltrexone.

      PubMed

      Vuoristo-Myllys, Salla; Lahti, Jari; Alho, Hannu; Julkunen, Juhani

      2013-11-01

      This study investigated predictors of dropout in an outpatient treatment program for problem drinking that included individual cognitive-behavioral therapy combined with naltrexone. Specifically, we investigated whether sociodemographic factors, severity of alcohol dependence, history of problem drinking, or intensity of alcohol craving assessed at the beginning of the treatment predicted dropout from an outpatient program among a sample of 372 patients (65% male). We also investigated whether the effectiveness of the treatment (the change in alcohol consumption and symptoms of alcohol craving) or adherence to naltrexone was related to dropout. Predictors of dropout were investigated using an analysis of covariance with the number of attended treatment sessions as an independent variable. Our results demonstrated that the treatment entry factors predictive of dropout were younger age, lower severity of alcohol dependence, better ability to resist and control alcohol use, and lower obsession with alcohol. In addition, those who dropped out were more likely to begin the program by abstaining from alcohol and had lower adherence to naltrexone use than those who completed the program. The length of stay for treatment was not related to change in alcohol consumption. Patients with less severe alcohol-related problems may lack motivation for treatment, specifically cognitive-behavioral therapy and naltrexone. These patients may benefit more from less intensive treatments.

    10. Low-Dose versus Standard-Dose Intravenous Alteplase in Acute Ischemic Stroke.

      PubMed

      Anderson, Craig S; Robinson, Thompson; Lindley, Richard I; Arima, Hisatomi; Lavados, Pablo M; Lee, Tsong-Hai; Broderick, Joseph P; Chen, Xiaoying; Chen, Guofang; Sharma, Vijay K; Kim, Jong S; Thang, Nguyen H; Cao, Yongjun; Parsons, Mark W; Levi, Christopher; Huang, Yining; Olavarría, Verónica V; Demchuk, Andrew M; Bath, Philip M; Donnan, Geoffrey A; Martins, Sheila; Pontes-Neto, Octavio M; Silva, Federico; Ricci, Stefano; Roffe, Christine; Pandian, Jeyaraj; Billot, Laurent; Woodward, Mark; Li, Qiang; Wang, Xia; Wang, Jiguang; Chalmers, John

      2016-06-16

      Thrombolytic therapy for acute ischemic stroke with a lower-than-standard dose of intravenous alteplase may improve recovery along with a reduced risk of intracerebral hemorrhage. Using a 2-by-2 quasi-factorial open-label design, we randomly assigned 3310 patients who were eligible for thrombolytic therapy (median age, 67 years; 63% Asian) to low-dose intravenous alteplase (0.6 mg per kilogram of body weight) or the standard dose (0.9 mg per kilogram); patients underwent randomization within 4.5 hours after the onset of stroke. The primary objective was to determine whether the low dose would be noninferior to the standard dose with respect to the primary outcome of death or disability at 90 days, which was defined by scores of 2 to 6 on the modified Rankin scale (range, 0 [no symptoms] to 6 [death]). Secondary objectives were to determine whether the low dose would be superior to the standard dose with respect to centrally adjudicated symptomatic intracerebral hemorrhage and whether the low dose would be noninferior in an ordinal analysis of modified Rankin scale scores (testing for an improvement in the distribution of scores). The trial included 935 patients who were also randomly assigned to intensive or guideline-recommended blood-pressure control. The primary outcome occurred in 855 of 1607 participants (53.2%) in the low-dose group and in 817 of 1599 participants (51.1%) in the standard-dose group (odds ratio, 1.09; 95% confidence interval [CI], 0.95 to 1.25; the upper boundary exceeded the noninferiority margin of 1.14; P=0.51 for noninferiority). Low-dose alteplase was noninferior in the ordinal analysis of modified Rankin scale scores (unadjusted common odds ratio, 1.00; 95% CI, 0.89 to 1.13; P=0.04 for noninferiority). Major symptomatic intracerebral hemorrhage occurred in 1.0% of the participants in the low-dose group and in 2.1% of the participants in the standard-dose group (P=0.01); fatal events occurred within 7 days in 0.5% and 1.5%, respectively

  1. Combining Varenicline (Chantix) with Naltrexone Decreases Alcohol Drinking More Effectively Than Does Either Drug Alone in a Rodent Model of Alcoholism.

    PubMed

    Froehlich, Janice C; Fischer, Stephen M; Dilley, Julian E; Nicholson, Emily R; Smith, Teal N; Filosa, Nick J; Rademacher, Logan C

    2016-09-01

    This study examined whether varenicline (VAR), or naltrexone (NTX), alone or in combination, reduces alcohol drinking in alcohol-preferring (P) rats with a genetic predisposition toward high voluntary alcohol intake. Alcohol-experienced P rats that had been drinking alcohol (15% v/v) for 2 h/d for 4 weeks were fed either vehicle (VEH), VAR alone (0.5, 1.0, or 2.0 mg/kg body weight [BW]), NTX alone (10.0, 15.0, or 20.0 mg/kg BW), or VAR + NTX in 1 of 4 dose combinations (0.5 VAR + 10.0 NTX, 0.5 VAR + 15.0 NTX, 1.0 VAR + 10.0 NTX, or 1.0 VAR + 15.0 NTX) at 1 hour prior to alcohol access for 10 consecutive days, and the effects on alcohol intake were assessed. When administered alone, VAR in doses of 0.5 or 1.0 mg/kg BW did not alter alcohol intake but a dose of 2.0 mg/kg BW decreased alcohol intake. This effect disappeared when drug treatment was terminated. NTX in doses of 10.0 and 15.0 mg/kg BW did not alter alcohol intake but a dose of 20.0 mg/kg BW decreased alcohol intake. Combining low doses of VAR and NTX into a single medication reduced alcohol intake as well as did high doses of each drug alone. Reduced alcohol intake occurred immediately after onset of treatment with the combined medication and continued throughout prolonged treatment. Low doses of VAR and NTX, when combined in a single medication, reduce alcohol intake in a rodent model of alcoholism. This approach has the advantage of reducing potential side effects associated with each drug. Lowering the dose of NTX and VAR in a combined treatment approach that maintains efficacy while reducing the incidence of negative side effects may increase patient compliance and improve clinical outcomes for alcoholics and heavy drinkers who want to reduce their alcohol intake. Copyright © 2016 by the Research Society on Alcoholism.

  2. Multidisciplinary European Low Dose Initiative (MELODI): strategic research agenda for low dose radiation risk research.

    PubMed

    Kreuzer, M; Auvinen, A; Cardis, E; Durante, M; Harms-Ringdahl, M; Jourdain, J R; Madas, B G; Ottolenghi, A; Pazzaglia, S; Prise, K M; Quintens, R; Sabatier, L; Bouffler, S

    2018-03-01

    MELODI (Multidisciplinary European Low Dose Initiative) is a European radiation protection research platform with focus on research on health risks after exposure to low-dose ionising radiation. It was founded in 2010 and currently includes 44 members from 18 countries. A major activity of MELODI is the continuous development of a long-term European Strategic Research Agenda (SRA) on low-dose risk for radiation protection. The SRA is intended to identify priorities for national and European radiation protection research programs as a basis for the preparation of competitive calls at the European level. Among those key priorities is the improvement of health risk estimates for exposures close to the dose limits for workers and to reference levels for the population in emergency situations. Another activity of MELODI is to ensure the availability of European key infrastructures for research activities, and the long-term maintenance of competences in radiation research via an integrated European approach for training and education. The MELODI SRA identifies three key research topics in low dose or low dose-rate radiation risk research: (1) dose and dose rate dependence of cancer risk, (2) radiation-induced non-cancer effects and (3) individual radiation sensitivity. The research required to improve the evidence base for each of the three key topics relates to three research lines: (1) research to improve understanding of the mechanisms contributing to radiogenic diseases, (2) epidemiological research to improve health risk evaluation of radiation exposure and (3) research to address the effects and risks associated with internal exposures, differing radiation qualities and inhomogeneous exposures. The full SRA and associated documents can be downloaded from the MELODI website ( http://www.melodi-online.eu/sra.html ).

  3. The Low-Mass Stellar Initial Mass Function: Ultra-Faint Dwarf Galaxies Revisited

    NASA Astrophysics Data System (ADS)

    Platais, Imants

    2017-08-01

    The stellar Initial Mass Function plays a critical role in the evolution of the baryonic content of the Universe. The form of the low-mass IMF - stars of mass less than the solar mass - determines the fraction of baryons locked up for a Hubble time, and thus indicates how gas and metals are cycled through galaxies. Inferences from resolved stellar populations, where the low-mass luminosity function and associated IMF can be derived from direct star counts, generally favor an invariant and universal IMF. However, a recent study of ultra-faint dwarf galaxies Hercules and Leo IV indicates a bottom-lite IMF, over a narrow range of stellar mass (only 0.55-0.75 M_sun), correlated with the internal velocity dispersion and/or metallicity. We propose to obtain ultra-deep imaging for a significantly closer ultra-faint dwarf, Bootes I, which will allow us to construct the luminosity function down to M_v=+10 (equivalent to 0.35 solar mass). We will also re-analyze the HST archival observations for the Hercules and Leo IV dwarfs using the same updated techniques as for Bootes I. The combined datasets should provide a reliable answer to the question of how variable is the low-mass stellar IMF.

  4. Energy deposition evaluation for ultra-low energy electron beam irradiation systems using calibrated thin radiochromic film and Monte Carlo simulations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Matsui, S., E-mail: smatsui@gpi.ac.jp; Mori, Y.; Nonaka, T.

    2016-05-15

    For evaluation of on-site dosimetry and process design in industrial use of ultra-low energy electron beam (ULEB) processes, we evaluate the energy deposition using a thin radiochromic film and a Monte Carlo simulation. The response of film dosimeter was calibrated using a high energy electron beam with an acceleration voltage of 2 MV and alanine dosimeters with uncertainty of 11% at coverage factor 2. Using this response function, the results of absorbed dose measurements for ULEB were evaluated from 10 kGy to 100 kGy as a relative dose. The deviation between the responses of deposit energy on the films andmore » Monte Carlo simulations was within 15%. As far as this limitation, relative dose estimation using thin film dosimeters with response function obtained by high energy electron irradiation and simulation results is effective for ULEB irradiation processes management.« less

  5. An ultra low power ECG signal processor design for cardiovascular disease detection.

    PubMed

    Jain, Sanjeev Kumar; Bhaumik, Basabi

    2015-08-01

    This paper presents an ultra low power ASIC design based on a new cardiovascular disease diagnostic algorithm. This new algorithm based on forward search is designed for real time ECG signal processing. The algorithm is evaluated for Physionet PTB database from the point of view of cardiovascular disease diagnosis. The failed detection rate of QRS complex peak detection of our algorithm ranges from 0.07% to 0.26% for multi lead ECG signal. The ASIC is designed using 130-nm CMOS low leakage process technology. The area of ASIC is 1.21 mm(2). This ASIC consumes only 96 nW at an operating frequency of 1 kHz with a supply voltage of 0.9 V. Due to ultra low power consumption, our proposed ASIC design is most suitable for energy efficient wearable ECG monitoring devices.

  6. Fatal and non-fatal opioid overdose in opioid dependent patients treated with methadone, buprenorphine or implant naltrexone.

    PubMed

    Kelty, Erin; Hulse, Gary

    2017-08-01

    Illicit opioid use is associated with high rates of fatal and non-fatal opioid overdose. This study aims to compare rates of fatal and serious but non-fatal opioid overdose in opioid dependent patients treated with methadone, buprenorphine or implant naltrexone, and to identify risk factors for fatal opioid overdose. Opioid dependent patients treated with methadone (n=3515), buprenorphine (n=3250) or implant naltrexone (n=1461) in Western Australia for the first time between 2001 and 2010, were matched against state mortality and hospital data. Rates of fatal and non-fatal serious opioid overdoses were calculated and compared for the three treatments. Risk factors associated with fatal opioid overdose were examined using multivariate cox proportional hazard models. No significant difference was observed between the three groups in terms of crude rates of fatal or non-fatal opioid overdoses. During the first 28days of treatment, rates of non-fatal opioid overdose were high in all three groups, as were fatal opioid overdoses in patients treated with methadone. However, no fatal opioid overdoses were observed in buprenorphine or naltrexone patients during this period. Following the first 28 days, buprenorphine was shown to be protective, particularly in terms of non-fatal opioid overdoses. After the cessation of treatment, rates of fatal and non-fatal opioid overdoses were similar between the groups, with the exception of lower rates of non-fatal opioid overdose in the naltrexone treated patients compared with the methadone treated patients. After the commencement of treatment, gender, and hospitalisations with a diagnosis of opioid poisoning, cardiovascular or mental health problems were significant predictors of subsequent fatal opioid overdose. Rates of fatal and non-fatal opioid overdose were not significantly different in patients treated with methadone, buprenorphine or implant naltrexone. Gender and prior cause-specific hospitalisations can be used to identify

  7. An Evaluation of μ-Opioid Receptor (OPRM1) as a Predictor of Naltrexone Response in the Treatment of Alcohol Dependence

    PubMed Central

    Anton, Raymond F.; Oroszi, Gabor; O'Malley, Stephanie; Couper, David; Swift, Robert; Pettinati, Helen; Goldman, David

    2008-01-01

    Context: Naltrexone hydrochloride treatment for alcohol dependence works for some individuals but not for everyone. Asn40Asp, a functional polymorphism of the μ-opioid receptor gene (OPRM1), might predict naltrexone response. Objective: To evaluate whether individuals with alcoholism who are heterozygous (Asp40/Asn40) or homozygous (Asp40/Asp40) for the OPRM1 Asp40 allele respond better to naltrexone. Design: Pharmacogenetic analysis conducted between January 1, 2001, and January 31, 2004. Setting: Eleven academic sites in the COMBINE Study. Participants: Recently abstinent volunteers who met all 3 of the following conditions: (1) DSM-IV criteria for primary alcohol dependence; (2) participation in the COMBINE Study; and (3) availability of DNA. Interventions: Alcoholic subjects were treated for 16 weeks with 100 mg of naltrexone hydrochloride (234 Asn40 homozygotes and 67 with at least 1 copy of the Asp40 allele) or placebo (235 Asn40 homozygotes and 68 with at least 1 copy of the Asp40 allele). All participants received medical management (MM) alone or with combined behavioral intervention (CBI). Main Outcome Measures: Time trends in percentage of days abstinent, percentage of heavy drinking days, and rates of good clinical outcome. Results: Alcoholic subjects with an Asp40 allele receiving MM alone (no CBI) had an increased percentage of days abstinent (P=.07) and a decreased percentage of heavy drinking days (P=.04) if treated with naltrexone vs placebo, while those with the Asn40/Asn40 genotype showed no medication differences. If treated with MM alone and naltrexone, 87.1% of Asp40 carriers had a good clinical outcome, compared with only 54.8% of individuals with the Asn40/Asn40 genotype (odds ratio, 5.75; confidence interval, 1.88-17.54), while, if treated with placebo, 48.6% of Asp40 carriers and 54.0% of individuals with the Asn40/Asn40 genotype had a good clinical outcome (interaction between medication and genotype, P=.005). No gene

  8. ULTRA-LOW POWER CO2 SENSOR FOR INTELLIGENT BUILDING CONTROL - PHASE I

    EPA Science Inventory

    The proposed EPA SBIR Phase I program will create a novel ultra-low power and low-cost microfabricated CO2 sensor. The initial developments of sensor technology will serve the very large Demand Controlled Ventilation market that has been identified by KWJ and its...

  9. Economic method for measuring ultra-low flow rates of fluids

    NASA Technical Reports Server (NTRS)

    Bogdanovic, J. A.; Keller, W. F.

    1970-01-01

    Capillary tube flowmeter measures ultra-low flows of very corrosive fluids /such as chlorine trifluoride and liquid fluorine/ and other liquids with reasonable accuracy. Flowmeter utilizes differential pressure transducer and operates on the principle that for laminar flow in the tube, pressure drop is proportional to flow rate.

  10. GRABGAM Analysis of Ultra-Low-Level HPGe Gamma Spectra

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Winn, W.G.

    The GRABGAM code has been used successfully for ultra-low level HPGe gamma spectrometry analysis since its development in 1985 at Savannah River Technology Center (SRTC). Although numerous gamma analysis codes existed at that time, reviews of institutional and commercial codes indicated that none addressed all features that were desired by SRTC. Furthermore, it was recognized that development of an in-house code would better facilitate future evolution of the code to address SRTC needs based on experience with low-level spectra. GRABGAM derives its name from Gamma Ray Analysis BASIC Generated At MCA/PC.

  11. Ultra-low noise supercontinuum source for ultra-high resolution optical coherence tomography at 1300 nm

    NASA Astrophysics Data System (ADS)

    Gonzalo, I. B.; Maria, M.; Engelsholm, R. D.; Feuchter, T.; Leick, L.; Moselund, P. M.; Podoleanu, A.; Bang, O.

    2018-02-01

    Supercontinuum (SC) sources are of great interest for many applications due to their ultra-broad optical bandwidth, good beam quality and high power spectral density [1]. In particular, the high average power over large bandwidths makes SC light sources excellent candidates for ultra-high resolution optical coherence tomography (UHR-OCT) [2-5]. However, conventional SC sources suffer from high pulse-to-pulse intensity fluctuations as a result of the noise-sensitive nonlinear effects involved in the SC generation process [6-9]. This intensity noise from the SC source can limit the performance of OCT, resulting in a reduced signal-to-noise ratio (SNR) [10-12]. Much work has been done to reduce the noise of the SC sources for instance with fiber tapers [7,8] or increasing the repetition rate of the pump laser for averaging in the spectrometer [10,12]. An alternative approach is to use all-normal dispersion (ANDi) fibers [13,14] to generate SC light from well-known coherent nonlinear processes [15-17]. In fact, reduction of SC noise using ANDi fibers compared to anomalous dispersion SC pumped by sub-picosecond pulses has been recently demonstrated [18], but a cladding mode was used to stabilize the ANDi SC. In this work, we characterize the noise performance of a femtosecond pumped ANDi based SC and a commercial SC source in an UHR-OCT system at 1300 nm. We show that the ANDi based SC presents exceptional noise properties compared to a commercial source. An improvement of 5 dB in SNR is measured in the UHR-OCT system, and the noise behavior resembles that of a superluminiscent diode. This preliminary study is a step forward towards development of an ultra-low noise SC source at 1300 nm for ultra-high resolution OCT.

  12. Intra-arterial Ultra-low-Dose CT Angiography of Lower Extremity in Diabetic Patients

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Özgen, Ali, E-mail: draliozgen@hotmail.com; Sanioğlu, Soner; Bingöl, Uğur Anıl

    2016-08-15

    PurposeTo image lower extremity arteries by CT angiography using a very low-dose intra-arterial contrast medium in patients with high risk of developing contrast-induced nephropathy (CIN).Materials and MethodsThree cases with long-standing diabetes mellitus and signs of lower extremity atherosclerotic disease were evaluated by CT angiography using 0.1 ml/kg of the body weight of contrast medium given via 10-cm-long 4F introducer by puncturing the CFA. Images were evaluated by an interventional radiologist and a cardiovascular surgeon. Density values of the lower extremity arteries were also calculated. Findings in two cases were compared with digital subtraction angiography images performed for percutaneous revascularization. Blood creatininemore » levels were followed for possible CIN.ResultsIntra-arterial CT angiography images were considered diagnostic in all patients and optimal in one patient. No patient developed CIN after intra-arterial CT angiography, while one patient developed CIN after percutaneous intervention.ConclusionIntra-arterial CT angiography of lower extremity might be performed in selected patients with high risk of developing CIN. Our limited experience suggests that as low as of 0.1 ml/kg of the body weight of contrast medium may result in adequate diagnostic imaging.« less

  13. Acute Myocardial Infarction following Naltrexone Consumption; a Case Report.

    PubMed

    Dadpour, Bita; Gholoobi, Arash; Tajoddini, Shahrad; Habibi, Amir

    2017-01-01

    Cardiovascular effects of opioid withdrawal have long been studied. It was reported that patients with underlying ischemic heart disease and atherosclerotic vessels may be complicated by a sudden physical and emotional stress due to withdrawal syndrome. But some other believes sudden increase in catecholamine level as a sympathetic overflow might effect on heart with and without underlying ischemia. In the current study, a patient on methadone maintenance therapy (MMT) who experienced myocardial infarction (MI) after taking naltrexone was described.

  14. Effects of alcoholism typology on response to naltrexone in the COMBINE study

    PubMed Central

    Bogenschutz, Michael P.; Tonigan, J. Scott; Pettinati, Helen M.

    2008-01-01

    Background This study investigated whether subgroups of alcohol dependent patients responded differently to naltrexone vs. placebo in the NIAAA COMBINE study. In particular, the A vs. B and the Early Onset vs. Late Onset typologies were examined. Relative to Type A alcoholics, Type Bs are characterized by greater severity, earlier onset, stronger family history, more childhood risk factors (e.g., conduct disorder), and greater frequency of comorbid psychiatric and substance use disorders. Methods COMBINE study participants were categorized as Type A or Type B using k-means cluster analysis and variables from 5 domains that have been shown to replicate the original Babor typology efficiently. Early Onset was defined as alcohol dependence beginning before age 25. For the planned analyses, the sample was reduced to the 618 participants receiving naltrexone alone or placebo, either with medical management (MM) alone or with MM plus the Combined Behavioral Intervention (CBI). The a priori primary outcome was percent heavy drinking days during treatment in the groups receiving MM without CBI. Results Among those receiving MM without CBI, Type A alcoholics had better drinking outcomes with naltrexone than placebo, whereas medication condition did not influence outcomes significantly in the Type Bs. Age of onset was not significantly related to outcome. For those receiving CBI, no significant effects were found for either typology. Conclusions In this sample, the beneficial effects of opioid antagonism were limited to Type A alcoholics receiving treatment in a medical management model. Future studies should investigate the relationship between clinically relevant genotypes, phenotypes such as typologies, and treatment response. More work is also needed to develop practical algorithms for phenotypic assignment. PMID:18828797

  15. Effects of alcoholism typology on response to naltrexone in the COMBINE study.

    PubMed

    Bogenschutz, Michael P; Scott Tonigan, J; Pettinati, Helen M

    2009-01-01

    This study investigated whether subgroups of alcohol-dependent patients responded differently to naltrexone versus placebo in the NIAAA COMBINE study. In particular, the A versus B and the Early Onset versus Late Onset typologies were examined. Relative to Type A alcoholics, Type B alcoholics are characterized by greater severity, earlier onset, stronger family history, more childhood risk factors (e.g., conduct disorder), and greater frequency of comorbid psychiatric and substance use disorders. COMBINE study participants were categorized as Type A or Type B using k-means cluster analysis and variables from 5 domains that have been shown to replicate the original Babor typology efficiently. Early Onset was defined as alcohol dependence beginning before age 25. For the planned analyses, the sample was reduced to the 618 participants receiving naltrexone alone or placebo, either with medical management (MM) alone or with MM plus the Combined Behavioral Intervention (CBI). The a priori primary outcome was percent heavy drinking days during treatment in the groups receiving MM without CBI. Among those receiving MM without CBI, Type A alcoholics had better drinking outcomes with naltrexone than placebo, whereas medication condition did not influence outcomes significantly in the Type Bs. Age of onset was not significantly related to outcome. For those receiving CBI, no significant effects were found for either typology. In this sample, the beneficial effects of opioid antagonism were limited to Type A alcoholics receiving treatment in a MM model. Future studies should investigate the relationship between clinically relevant genotypes, phenotypes such as typologies, and treatment response. More work is also needed to develop practical algorithms for phenotypic assignment.

  16. A low power cryocooled autonomous ultra-stable oscillator

    NASA Astrophysics Data System (ADS)

    Fluhr, C.; Dubois, B.; Grop, S.; Paris, J.; Le Tetû, G.; Giordano, V.

    2016-12-01

    We present the design and the preliminary evaluation of a cryostat equipped with a low power pulse-tube cryocooler intended to maintain near 5 K a high-Q factor sapphire microwave resonator. This cooled resonator constitutes the frequency reference of an ultra-stable oscillator presenting a short term fractional frequency stability of better than 1 ×10-15 . The proposed design enables to reach a state-of-the-art frequency stability with a cryogenic oscillator consuming only 3 kW of electrical power.

  17. Ultra-low-power conversion and management techniques for thermoelectric energy harvesting applications

    NASA Astrophysics Data System (ADS)

    Fleming, Jerry W.

    2010-04-01

    Thermoelectric energy harvesting has increasingly gained acceptance as a potential power source that can be used for numerous commercial and military applications. However, power electronic designers have struggled to incorporate energy harvesting methods into their designs due to the relatively small voltage levels available from many harvesting device technologies. In order to bridge this gap, an ultra-low input voltage power conversion method is needed to convert small amounts of scavenged energy into a usable form of electricity. Such a method would be an enabler for new and improved medical devices, sensor systems, and other portable electronic products. This paper addresses the technical challenges involved in ultra-low-voltage power conversion by providing a solution utilizing novel power conversion techniques and applied technologies. Our solution utilizes intelligent power management techniques to control unknown startup conditions. The load and supply management functionality is also controlled in a deterministic manner. The DC to DC converter input operating voltage is 20mV with a conversion efficiency of 90% or more. The output voltage is stored into a storage device such as an ultra-capacitor or lithium-ion battery for use during brown-out or unfavorable harvesting conditions. Applications requiring modular, low power, extended maintenance cycles, such as wireless instrumentation would significantly benefit from the novel power conversion and harvesting techniques outlined in this paper.

  18. Effect of Diluent on Ultra-low Temperature Curable Conductive Silver Adhesive

    NASA Astrophysics Data System (ADS)

    Zhou, Xingli; Wang, Likun; Liao, Qingwei; Yan, Chao; Du, Haibo; Qin, Lei

    2018-03-01

    The ultra-low temperature curable conductive silver adhesive needed urgently for the surface conductive treatment of piezoelectric composite material. The effect of diluent acetone on ultra-low temperature curable conductive silver adhesive were investigated for surface conductive treatment of piezoelectric composite material. In order to improve the operability and extend the life of the conductive adhesive, the diluent was added to dissolve and disperse conductive adhesive. With the increase of the content of diluent, the volume resistivity of conductive adhesive decreased at first and then increased, and the shear strength increased at first and then decreased. When the acetone content is 10%, the silver flaky bonded together, arranged the neatest, the smallest gap, the most closely connected, the surface can form a complete conductive network, and the volume resistivity is 2.37 × 10-4Ω · cm, the shear strength is 5.13MPa.

  19. Radon Exposure and the Definition of Low Doses-The Problem of Spatial Dose Distribution.

    PubMed

    Madas, Balázs G

    2016-07-01

    Investigating the health effects of low doses of ionizing radiation is considered to be one of the most important fields in radiological protection research. Although the definition of low dose given by a dose range seems to be clear, it leaves some open questions. For example, the time frame and the target volume in which absorbed dose is measured have to be defined. While dose rate is considered in the current system of radiological protection, the same cancer risk is associated with all exposures, resulting in a given amount of energy absorbed by a single target cell or distributed among all the target cells of a given organ. However, the biological effects and so the health consequences of these extreme exposure scenarios are unlikely to be the same. Due to the heterogeneous deposition of radon progeny within the lungs, heterogeneous radiation exposure becomes a practical issue in radiological protection. While the macroscopic dose is still within the low dose range, local tissue doses on the order of Grays can be reached in the most exposed parts of the bronchial airways. It can be concluded that progress in low dose research needs not only low dose but also high dose experiments where small parts of a biological sample receive doses on the order of Grays, while the average dose over the whole sample remains low. A narrow interpretation of low dose research might exclude investigations with high relevance to radiological protection. Therefore, studies important to radiological protection should be performed in the frame of low dose research even if the applied doses do not fit in the dose range used for the definition of low doses.

  20. Diffusion of naltrexone across reconstituted human oral epithelium and histomorphological features.

    PubMed

    Giannola, Libero Italo; De Caro, Viviana; Giandalia, Giulia; Siragusa, Maria Gabriella; Campisi, Giuseppina; Florena, Ada Maria; Ciach, Tomasz

    2007-02-01

    In transbuccal absorption a major limitation could be the low permeability of the mucosa which implies low drug bioavailability. The ability of naltrexone hydrochloride (NLX) to penetrate a resembling histologically human buccal mucosa was assessed and the occurrence of any histomorphological changes observed. We used reconstituted human oral (RHO) non-keratinised epithelium as mucosal section and a Transwell diffusion cells system as bicompartmental model. Buccal permeation was expressed in terms of drug flux (J(s)) and permeability coefficients (K(p)). Data were collected using both artificial and natural human saliva. The main finding was that RHO does not restrain NLX permeation. Drug transport across the epithelium was observed also in presence of various concentrations of penetration enhancers, without any significant differences. On the contrary, the flux throughout the mucosa was extensively affected by iontophoresis. Histologically, no sign of flogosis was observed in any specimen under experiment without iontophoresis, whereas cytoarchitectural changes, up to nuclear pycnosis or cellular swelling, were determined as a consequence of the application of electric fields.

  1. Cryogenic ultra-low-noise SiGe transistor amplifier.

    PubMed

    Ivanov, B I; Trgala, M; Grajcar, M; Il'ichev, E; Meyer, H-G

    2011-10-01

    An ultra-low-noise one-stage SiGe heterojunction bipolar transistor amplifier was designed for cryogenic temperatures and a frequency range of 10 kHz-100 MHz. A noise temperature T(N) ≈ 1.4 K was measured at an ambient temperature of 4.2 K at frequencies between 100 kHz and 100 MHz for a source resistance of ~50 Ω. The voltage gain of the amplifier was 25 dB at a power consumption of 720 μW. The input voltage noise spectral density of the amplifier is about 35 pV/√Hz. The low noise resistance and power consumption makes the amplifier suitable for readout of resistively shunted DC SQUID magnetometers and amplifiers.

  2. The Placebo Effect in Clinical Trials for Alcohol Dependence: An Exploratory Analysis of 51 Naltrexone and Acamprosate Studies

    PubMed Central

    Litten, Raye Z.; Castle, I-Jen P.; Falk, Daniel; Ryan, Megan; Fertig, Joanne; Chen, Chiung M.; Yi, Hsiao-ye

    2013-01-01

    Background The placebo effect often undermines efforts to determine treatment effectiveness in clinical trials. A significant placebo response occurs in alcohol trials, but it is not well understood. The purpose of this study was to characterize the placebo response across multiple naltrexone and acamprosate studies. Methods Fifty-one trials, 3 with a naltrexone and an acamprosate arm, 31 with at least 1 naltrexone arm, and 17 with at least 1 acamprosate arm, were identified from Cochrane reviews and PubMed search. To be included in this study, patients had to be at least 18 years old, abstinent from alcohol before randomization, and meet a diagnosis of alcohol dependence. Pearson correlation coefficients (rp) and simple linear regression were used to describe the strength of linear relationships between placebo response and treatment effect size. Spearman’s rank correlation coefficients (rs) were used to examine the strength of associations between study characteristics and placebo response. Results For the end-point measures of percent days abstinent and total abstinence, a negative relationship was evident between placebo response and treatment effect size in the naltrexone trials (rp = −0.55, p < 0.01 and rp = −0.20, p = 0.35, respectively) as well as in the acamprosate trials (rp = −0.45, p = 0.09 and rp = −0.56, p = 0.01, respectively). The placebo response for percent days abstinent was negatively correlated with mean age of participants (rs = −0.42, p = 0.05) across naltrexone trials and positively correlated with publication year (rs = 0.57, p = 0.03) across acamprosate trials. However, these two study characteristics were not significantly correlated with treatment effect size. Conclusion The placebo response varied considerably across trials and was negatively correlated with the treatment effect size. Additional studies are required to fully understand the complex nature of the placebo response and to evaluate approaches to minimize its

  3. Survival of tumor cells after proton irradiation with ultra-high dose rates

    PubMed Central

    2011-01-01

    Background Laser acceleration of protons and heavy ions may in the future be used in radiation therapy. Laser-driven particle beams are pulsed and ultra high dose rates of >109 Gy s-1may be achieved. Here we compare the radiobiological effects of pulsed and continuous proton beams. Methods The ion microbeam SNAKE at the Munich tandem accelerator was used to directly compare a pulsed and a continuous 20 MeV proton beam, which delivered a dose of 3 Gy to a HeLa cell monolayer within < 1 ns or 100 ms, respectively. Investigated endpoints were G2 phase cell cycle arrest, apoptosis, and colony formation. Results At 10 h after pulsed irradiation, the fraction of G2 cells was significantly lower than after irradiation with the continuous beam, while all other endpoints including colony formation were not significantly different. We determined the relative biological effectiveness (RBE) for pulsed and continuous proton beams relative to x-irradiation as 0.91 ± 0.26 and 0.86 ± 0.33 (mean and SD), respectively. Conclusions At the dose rates investigated here, which are expected to correspond to those in radiation therapy using laser-driven particles, the RBE of the pulsed and the (conventional) continuous irradiation mode do not differ significantly. PMID:22008289

  4. Analysis and Design of Rotors at Ultra-Low Reynolds Numbers

    NASA Technical Reports Server (NTRS)

    Kunz, Peter J.; Strawn, Roger C.

    2003-01-01

    Design tools have been developed for ultra-low Reynolds number rotors, combining enhanced actuator-ring / blade-element theory with airfoil section data based on two-dimensional Navier-Stokes calculations. This performance prediction method is coupled with an optimizer for both design and analysis applications. Performance predictions from these tools have been compared with three-dimensional Navier Stokes analyses and experimental data for a 2.5 cm diameter rotor with chord Reynolds numbers below 10,000. Comparisons among the analyses and experimental data show reasonable agreement both in the global thrust and power required, but the spanwise distributions of these quantities exhibit significant deviations. The study also reveals that three-dimensional and rotational effects significantly change local airfoil section performance. The magnitude of this issue, unique to this operating regime, may limit the applicability of blade-element type methods for detailed rotor design at ultra-low Reynolds numbers, but these methods are still useful for evaluating concept feasibility and rapidly generating initial designs for further analysis and optimization using more advanced tools.

  5. Determination of naltrexone and 6beta-naltrexol in human blood: comparison of high-performance liquid chromatography with spectrophotometric and tandem-mass-spectrometric detection.

    PubMed

    Brünen, Sonja; Krüger, Ralf; Finger, Susann; Korf, Felix; Kiefer, Falk; Wiedemann, Klaus; Lackner, Karl J; Hiemke, Christoph

    2010-02-01

    We present data for a comparison of a liquid-chromatographic method coupled with tandem mass spectrometry (LC-MS/MS) and a high-performance liquid-chromatographic method with column switching and UV spectrophotometric detection. The two methods were developed for determination of naltrexone and 6beta-naltrexol in blood serum or plasma aiming to be used for therapeutic drug monitoring to guide the treatment of patients with naltrexone. For the high-performance liquid chromatography (HPLC)/UV detection, online sample cleanup was conducted on Perfect Bond C(18) material with 2% (vol/vol) acetonitrile in deionized water. Drugs were separated on a C(18) column using 11.5% (vol/vol) acetonitrile and 0.4% (vol/vol) N,N,N,N-tetramethylethylenediamine within 20 min. LC-MS/MS used naltrexone-d (3) and 6beta-naltrexol-d (4) as internal standards. After protein precipitation, the chromatographic separation was performed on a C(18) column by applying a methanol gradient (5-100%, vol/vol) with 0.1% formic acid over 9.5 min. The HPLC/UV method was found to be linear for concentrations ranging from 2 to 100 ng/ml, with a regression correlation coefficient of r (2) > 0.998 for naltrexone and 6beta-naltrexol. The limit of quantification was 2 ng/ml for naltrexone and 6beta-naltrexol. For the LC-MS/MS method the calibration curves were linear (r(2) > 0.999) from 0.5 to 200 ng/ml for both substances, and the limit of quantification was 0.5 ng/ml. The concentrations measured by the two methods correlated significantly for both substances (r(2) > 0.967; p < 0.001). Both methods could be used for therapeutic drug monitoring. The HPLC/UV method was advantageous regarding automatization and costs, whereas LC-MS/MS was superior with regard to sensitivity.

  6. Study of ultra-low emittance design for SPEAR3

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, M. -H.; Huang, X.; Safranek, J.

    2015-09-17

    Since its 2003 construction, the SPEAR3 synchrotron light source at SLAC has continuously improved its performance by raising beam current, top-off injection, and smaller emittance. This makes SPEAR3 one of the most productive light sources in the world. Now, to further enhance the performance of SPEAR3, we are looking into the possibility of converting SPEAR3 to an ultra-low emittance storage ring within its site constraint.

  7. Design of nodes for embedded and ultra low-power wireless sensor networks

    NASA Astrophysics Data System (ADS)

    Xu, Jun; You, Bo; Cui, Juan; Ma, Jing; Li, Xin

    2008-10-01

    Sensor network integrates sensor technology, MEMS (Micro-Electro-Mechanical system) technology, embedded computing, wireless communication technology and distributed information management technology. It is of great value to use it where human is quite difficult to reach. Power consumption and size are the most important consideration when nodes are designed for distributed WSN (wireless sensor networks). Consequently, it is of great importance to decrease the size of a node, reduce its power consumption and extend its life in network. WSN nodes have been designed using JN5121-Z01-M01 module produced by jennic company and IEEE 802.15.4/ZigBee technology. Its new features include support for CPU sleep modes and a long-term ultra low power sleep mode for the entire node. In low power configuration the node resembles existing small low power nodes. An embedded temperature sensor node has been developed to verify and explore our architecture. The experiment results indicate that the WSN has the characteristic of high reliability, good stability and ultra low power consumption.

  8. Bupropion-SR plus naltrexone-SR for the treatment of mild-to-moderate obesity.

    PubMed

    Ali, Khawla F; Shukla, Alpana P; Aronne, Louis J

    2016-01-01

    Naltrexone-bupropion is a recently approved drug combination for chronic weight management. In this article, we discuss the rationale for its use as a combination followed by a comprehensive review of safety and efficacy data from major preclinical, phase II and III clinical trials.

  9. Ultra-low current biosensor output detection using portable electronic reader

    NASA Astrophysics Data System (ADS)

    Yahaya, N. A. N.; Rajapaksha, R. D. A. A.; Uda, M. N. Afnan; Hashim, U.

    2017-09-01

    Generally, the electrical biosensor usually shows extremely low current signal output around pico ampere to microampere range. In this research, electronic reader with amplifier has been demonstrated to detect ultra low current via the biosensor. The operational amplifier Burr-Brown OPA 128 and Arduino Uno board were used to construct the portable electronic reader. There are two cascaded inverting amplifier were used to detect ultra low current through the biosensor from pico amperes (pA) to nano amperes ranges (nA). A small known input current was form by applying variable voltage between 0.1V to 5.0V across a 5GΩ high resistor to check the amplifier circuit. The amplifier operation was measured with the high impedance current source and has been compared with the theoretical measurement. The Arduino Uno was used to convert the analog signal to digital signal and process the data to display on reader screen. In this project, Proteus software was used to design and test the circuit. Then it was implemented together with Arduino Uno board. Arduino board was programmed using C programming language to make whole circuit communicate each order. The current was measured then it shows a small difference values compared to theoretical values, which is approximately 14pA.

  10. [Reparative Osteogenesis and Angiogenesis in Low Intensity Electromagnetic Radiation of Ultra-High Frequency].

    PubMed

    Iryanov, Y M; Kiryanov, N A

    2015-01-01

    Non-drug correction of reparative bone tissue regeneration in different pathological states - one of the most actual problems of modern medicine. Our aim was to conduct morphological analysis of the influence of electromagnetic radiation of ultra-high frequency and low intensity on reparative osteogenesis and angiogenesis in fracture treatment under transosseous osteosynthesis. A controlled nonrandomized study was carried out. In the experiment conducted on rats we modeled tibial fracture with reposition and fixation of the bone fragments both in control and experimental groups. In the animals of the experimental group the fracture zone was exposed to low intensity electromagnetic radiation of ultra-high frequency. Exposure simulation was performed in the control group. The operated bones were examined using radiography, light and electronic microscopy, X-ray electronic probe microanalysis. It has been established that electromagnetic radiation of ultra-high frequency sessions in fracture treatment stimulate secretory activity and degranulation of mast cells, produce microcirculatory bed vascular permeability increase, endotheliocyte migration phenotype expression, provide endovascular endothelial outgrowth formation, activate reparative osteogenesis and angiogenesis while fracture reparation becomes the one of the primary type. The full periosteal, intermediary and intraosteal bone union was defined in 28 days. Among the therapeutic benefits of electromagnetic radiation of ultra-high frequency in fracture treatment we can detect mast cell secretorv activity stimulation and endovascular anziozenesis activation.

  11. Development of Ultra-Low-Noise TES Bolometer Arrays

    NASA Astrophysics Data System (ADS)

    Suzuki, T.; Khosropanah, P.; Ridder, M. L.; Hijmering, R. A.; Gao, J. R.; Akamatsu, H.; Gottardi, L.; van der Kuur, J.; Jackson, B. D.

    2016-07-01

    SRON is developing ultra-low-noise transition edge sensors (TESs) based on a superconducting Ti/Au bilayer on a suspended SiN island with SiN legs for SAFARI aboard SPICA. We have two major concerns about realizing TESs with an ultra-low NEP of 2× 10^{-19} hbox {W}/√{{ {Hz}}}: achieving lower thermal conductance and no excess noise with respect to the phonon noise. To realize TESs with phonon-noise-limited NEPs, we need to make thinner ({<}0.25 \\upmu hbox {m}) and narrower ({<}1 \\upmu hbox {m}) SiN legs. With deep reactive-ion etching, three types of TESs were fabricated in combination with different SiN island sizes and the presence or absence of an optical absorber. Those TESs have a thin (0.20 \\upmu hbox {m}), narrow (0.5-0.7 \\upmu hbox {m}), and long (340-460 \\upmu hbox {m}) SiN legs and show Tc of {˜ }93 hbox {mK} and Rn of {˜ }158 hbox {m}{Ω }. These TESs were characterized under AC bias using our frequency-division multiplexing readout (1-3 MHz) system. TESs without the absorber show NEPs as low as 1.1 × 10^{-19} hbox {W}/√{{ {Hz}}} with a reasonable response speed ({<}1 hbox {ms}), which achieved the phonon noise limit. For TESs with the absorber, we confirmed a higher hbox {NEP}_{el} ({˜ }5 × 10^{-19} hbox {W}/√{{ {Hz}}}) than that of TESs without the absorber likely due to stray light. The lowest NEP can make the new version of SAFARI with a grating spectrometer feasible.

  12. Ultra-Low-Power Cryogenic SiGe Low-Noise Amplifiers: Theory and Demonstration

    NASA Astrophysics Data System (ADS)

    Montazeri, Shirin; Wong, Wei-Ting; Coskun, Ahmet H.; Bardin, Joseph C.

    2016-01-01

    Low-power cryogenic low-noise amplifiers (LNAs) are desired to ease the cooling requirements of ultra-sensitive cryogenically cooled instrumentation. In this paper, the tradeoff between power and noise performance in silicon-germanium LNAs is explored to study the possibility of operating these devices from low supply voltages. A new small-signal heterojunction bipolar transistor noise model applicable to both the forward-active and saturation regimes is developed from first principles. Experimental measurements of a device across a wide range of temperatures are then presented and the dependence of the noise parameters on collector-emitter voltage is described. This paper concludes with the demonstration of a high-gain 1.8-3.6-GHz cryogenic LNA achieving a noise temperature of 3.4-5 K while consuming just 290 μW when operating at 15-K physical temperature.

  13. Evaluating the Impact of Naltrexone on the Rat Gambling Task to Test Its Predictive Validity for Gambling Disorder.

    PubMed

    Di Ciano, Patricia; Le Foll, Bernard

    2016-01-01

    Gambling Disorder has serious consequences and no medications are currently approved for the treatment of this disorder. One factor that may make medication development difficult is the lack of animal models of gambling that would allow for the pre-clinical screening of efficacy. Despite this, there is evidence from clinical trials that opiate antagonists, in particular naltrexone, may be useful in treating gambling disorder. To-date, the effects of naltrexone on pre-clinical models of gambling have not been evaluated. The purpose of the present study was to evaluate the effects of naltrexone in an animal model of gambling, the rat gambling task (rGT), to determine whether this model has some predictive validity. The rGT is a model in which rats are given a choice of making either a response that produces a large reward or a small reward. The larger the reward, the greater the punishment, and thus this task requires that the animal inhibit the 'tempting' choice, as the smaller reward option produces overall the most number of rewards per session. People with gambling disorder chose the tempting option more, thus the rGT may provide a model of problem gambling. It was found that naltrexone improved performance on this task in a subset of animals that chose the 'tempting', disadvantageous choice, more at baseline. Thus, the results of this study suggest that the rGT should be further investigated as a pre-clinical model of gambling disorder and that further investigation into whether opioid antagonists are effective in treating Gambling Disorder may be warranted.

  14. Dosimetry Modeling for Focal Low-Dose-Rate Prostate Brachytherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Al-Qaisieh, Bashar; Mason, Josh, E-mail: joshua.mason@nhs.net; Bownes, Peter

    2015-07-15

    Purpose: Focal brachytherapy targeted to an individual lesion(s) within the prostate may reduce side effects experienced with whole-gland brachytherapy. The outcomes of a consensus meeting on focal prostate brachytherapy were used to investigate optimal dosimetry of focal low-dose-rate (LDR) prostate brachytherapy targeted using multiparametric magnetic resonance imaging (mp-MRI) and transperineal template prostate mapping (TPM) biopsy, including the effects of random and systematic seed displacements and interseed attenuation (ISA). Methods and Materials: Nine patients were selected according to clinical characteristics and concordance of TPM and mp-MRI. Retrospectively, 3 treatment plans were analyzed for each case: whole-gland (WG), hemi-gland (hemi), and ultra-focalmore » (UF) plans, with 145-Gy prescription dose and identical dose constraints for each plan. Plan robustness to seed displacement and ISA were assessed using Monte Carlo simulations. Results: WG plans used a mean 28 needles and 81 seeds, hemi plans used 17 needles and 56 seeds, and UF plans used 12 needles and 25 seeds. Mean D90 (minimum dose received by 90% of the target) and V100 (percentage of the target that receives 100% dose) values were 181.3 Gy and 99.8% for the prostate in WG plans, 195.7 Gy and 97.8% for the hemi-prostate in hemi plans, and 218.3 Gy and 99.8% for the focal target in UF plans. Mean urethra D10 was 205.9 Gy, 191.4 Gy, and 92.4 Gy in WG, hemi, and UF plans, respectively. Mean rectum D2 cm{sup 3} was 107.5 Gy, 77.0 Gy, and 42.7 Gy in WG, hemi, and UF plans, respectively. Focal plans were more sensitive to seed displacement errors: random shifts with a standard deviation of 4 mm reduced mean target D90 by 14.0%, 20.5%, and 32.0% for WG, hemi, and UF plans, respectively. ISA has a similar impact on dose-volume histogram parameters for all plan types. Conclusions: Treatment planning for focal LDR brachytherapy is feasible. Dose constraints are easily met with a

  15. Carbon transfer from magnesia-graphite ladle refractories to ultra-low carbon steel

    NASA Astrophysics Data System (ADS)

    Russo, Andrew Arthur

    Ultra-low carbon steels are utilized in processes which require maximum ductility. Increases in interstitial carbon lower the ductility of steel; therefore, it is important to examine possible sources of carbon. The refractory ladle lining is one such source. Ladle refractories often contain graphite for its desirable thermal shock and slag corrosion resistance. This graphite is a possible source of carbon increase in ultra-low carbon steels. The goal of this research is to understand and evaluate the mechanisms by which carbon transfers to ultra-low carbon steel from magnesia-graphite ladle refractory. Laboratory dip tests were performed in a vacuum induction furnace under an argon atmosphere to investigate these mechanisms. Commercial ladle refractories with carbon contents between 4-12 wt% were used to investigate the effect of refractory carbon content. Slag-free dip tests and slag-containing dip tests with varying MgO concentrations were performed to investigate the influence of slag. Carbon transfer to the steel was controlled by steel penetrating into the refractory and dissolving carbon in dip tests where no slag was present. The rate limiting step for this mechanism is convective mass transport of carbon into the bulk steel. No detectable carbon transfer occurred in dip tests with 4 and 6 wt%C refractories without slag because no significant steel penetration occurred. Carbon transfer was controlled by the corrosion of refractory by slag in dip tests where slag was present.

  16. Ultra-Shallow Junctions Fabrication by Plasma Immersion Implantation on PULSION registered Followed by Laser Thermal Processing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Torregrosa, Frank; Etienne, Hasnaa; Sempere, Guillaume

    In order to achieve the requirements for P+/N junctions for <45 nm ITRS nodes, ultra low energy and high dose implantations are needed. Classical beamline implantation is now limited in low energies, compared to Plasma Immersion Ion Implantation (PIII) which efficiency is no more to prove for the realization of Ultra-Shallow Junctions (USJ) in semiconductor applications : this technique allows to get ultimate shallow profiles (as implanted) due to no lower limitation of energy and high dose rate. Electrical activation is also a big issue since it has to afford high electrical activation rate with very low diffusion. Laser annealingmore » is one of the candidates for the 45 nm node. This paper presents electrical and physico-chemical characterizations of junctions realized with BF3 PIII followed by laser thermal processing with aim to obtain ultra-shallow junctions. Different implantation conditions (acceleration voltage/dose) and laser conditions (laser types, fluence/number of shots) are used for this study. Pre-amorphization is also used to confine the junction depth, and is shown to have a positive effect on junction depth but leads in higher junction leakage due to the remaining of EOR defects. The characterization is done using Optical characterization tool (SEMILAB) for sheet resistance and junction leakage measurements. SIMS is used for Boron profile and junction depth.« less

  17. A Pilot Study of Naltrexone and BASICS for Heavy Drinking Young Adults

    PubMed Central

    Leeman, Robert F.; Palmer, Rebekka S.; Corbin, William R.; Romano, Denise M.; Meandzija, Boris; O’Malley, Stephanie S.

    2008-01-01

    Heavy drinking young adults often have limited motivation to change their drinking behavior. Adding pharmacotherapy to brief counseling is a novel approach to treating this population. A small open-label pilot study was conducted to assess the feasibility of offering eight weeks of daily and targeted (i.e., taken as needed in anticipation of drinking) naltrexone with BASICS (brief motivational) counseling to heavy drinking young adults; to assess the tolerability of the medication in this population and to obtain preliminary efficacy data. The sample (N = 14) showed strong adherence to study appointments and medication taking, supporting the feasibility of this approach. Overall, the medication was well-tolerated. Significant reductions from baseline were observed in drinks per drinking day and in percent heavy drinking days and these gains were maintained one month after treatment ended. A significant decrease in alcohol-related consequences was also observed. Findings from this small pilot study suggest that naltrexone in combination with BASICS represents a promising strategy to reduce heavy drinking among young adults. PMID:18502591

  18. A flexible nanobrush pad for the chemical mechanical planarization of Cu/ultra-low-к materials

    NASA Astrophysics Data System (ADS)

    Han, Guiquan; Liu, Yuhong; Lu, Xinchun; Luo, Jianbin

    2012-10-01

    A new idea of polishing pad called flexible nanobrush pad (FNP) has been proposed for the low down pressure chemical mechanical planarization (CMP) process of Cu/ultra-low-к materials. The FNP was designed with a surface layer of flexible brush-like nanofibers which can `actively' carry nanoscale abrasives in slurry independent of the down pressure. Better planarization performances including high material removal rate, good planarization, good polishing uniformity, and low defectivity are expected in the CMP process under the low down pressure with such kind of pad. The FNP can be made by template-assisted replication or template-based synthesis methods, which will be driven by the development of the preparation technologies for ordered nanostructure arrays. The present work would potentially provide a new solution for the Cu/ultra-low-к CMP process.

  19. [Electric traction magnetic fields of ultra-low frequency as an occupational risk factor of ischemic heart disease].

    PubMed

    Ptitsyna, N G; Kudrin, V A; Villorezi, D; Kopytenko, Iu A; Tiasto, M I; Kopytenko, E A; Bochko, V A; Iuchchi, N

    1996-01-01

    The study was inspired by earlier results that displayed influence of variable natural geomagnetic field (0.005-10 Hz range-ultra-low frequencies) on circulatory system, indicated possible correlation between industrial ultra-low frequency fields and prevalence of myocardial infarction. The authors conducted unique measurements of ultra-low frequency fields produced by electric engines. The results were compared with data on morbidity among railway transport workers. The findings are that level of magnetic variations in electric locomotive cabin can exceed 280 micro Tesla, whereas that in car sections reaches 50 micro Tesla. Occurrence of coronary heart disease among the locomotive operators appeared to be 2.0 + 0.2 times higher than that among the car section operators. Higher risk of coronary heart disease in the locomotive operators is associated with their increased occupational magnetic load.

  20. An Ultra Low Cost Wireless Communications Laboratory for Education and Research

    ERIC Educational Resources Information Center

    Linn, Y.

    2012-01-01

    This paper presents an ultra-low-cost wireless communications laboratory that is based on a commercial off-the-shelf field programmable gate array (FPGA) development board that is both inexpensive and available worldwide. The total cost of the laboratory is under USD $200, but it includes complete transmission, channel emulation, reception…

  1. Cessation of Long-Term Naltrexone Therapy and Self-Injury: A Case Study.

    ERIC Educational Resources Information Center

    Crews, W. David, Jr.; And Others

    1993-01-01

    This case study of a woman with profound mental retardation and a history of severe self-injurious behavior (SIB) found that the dramatic decrease in SIB following Naltrexone administration was maintained through placebo and no drug phases and at six-month follow-up. Findings are discussed in terms of endogenous opioid system theories of SIB. (DB)

  2. Ultra-low-mass flexible planar solar arrays using 50-micron-thick solar cells

    NASA Technical Reports Server (NTRS)

    Costogue, E. N.; Rayl, G.

    1978-01-01

    A conceptual design study has been completed which has shown the feasibility of ultra-low-mass planar solar arrays with specific power of 200 watts/kilogram. The beginning of life (BOL) power output of the array designs would be 10 kW at 1 astronomical unit (AU) and a 55C deg operating temperature. Two designs were studied: a retractable rollout design and a non-retractable fold-out. The designs employed a flexible low-mass blanket and low-mass structures. The blanket utilized 2 x 2 cm high-efficiency (13.5% at 28C deg AM0), ultra-thin (50 micron), silicon solar cells protected by thin (75 micron) plastic encapsulants. The structural design utilized the 'V'-stiffened approach which allows a lower mass boom to be used. In conjunction with the conceptual design, modules using the thin cells and plastic encapsulant were designed and fabricated.

  3. Accuracy of lung nodule volumetry in low-dose CT with iterative reconstruction: an anthropomorphic thoracic phantom study.

    PubMed

    Doo, K W; Kang, E-Y; Yong, H S; Woo, O H; Lee, K Y; Oh, Y-W

    2014-09-01

    The purpose of this study was to assess accuracy of lung nodule volumetry in low-dose CT with application of iterative reconstruction (IR) according to nodule size, nodule density and CT tube currents, using artificial lung nodules within an anthropomorphic thoracic phantom. Eight artificial nodules (four diameters: 5, 8, 10 and 12 mm; two CT densities: -630 HU that represents ground-glass nodule and +100 HU that represents solid nodule) were randomly placed inside a thoracic phantom. Scans were performed with tube current-time product to 10, 20, 30 and 50 mAs. Images were reconstructed with IR and filtered back projection (FBP). We compared volume estimates to a reference standard and calculated the absolute percentage error (APE). The APE of all nodules was significantly lower when IR was used than with FBP (7.5 ± 4.7% compared with 9.0 ±6.9%; p < 0.001). The effect of IR was more pronounced for smaller nodules (p < 0.001). IR showed a significantly lower APE than FBP in ground-glass nodules (p < 0.0001), and the difference was more pronounced at the lowest tube current (11.8 ± 5.9% compared with 21.3 ± 6.1%; p < 0.0001). The effect of IR was most pronounced for ground-glass nodules in the lowest CT tube current. Lung nodule volumetry in low-dose CT by application of IR showed reliable accuracy in a phantom study. Lung nodule volumetry can be reliably applicable to all lung nodules including small, ground-glass nodules even in ultra-low-dose CT with application of IR. IR significantly improved the accuracy of lung nodule volumetry compared with FBP particularly for ground-glass (-630 HU) nodules. Volumetry in low-dose CT can be utilized in patient with lung nodule work-up, and IR has benefit for small, ground-glass lung nodules in low-dose CT.

  4. Low-dose effects of hormones and endocrine disruptors.

    PubMed

    Vandenberg, Laura N

    2014-01-01

    Endogenous hormones have effects on tissue morphology, cell physiology, and behaviors at low doses. In fact, hormones are known to circulate in the part-per-trillion and part-per-billion concentrations, making them highly effective and potent signaling molecules. Many endocrine-disrupting chemicals (EDCs) mimic hormones, yet there is strong debate over whether these chemicals can also have effects at low doses. In the 1990s, scientists proposed the "low-dose hypothesis," which postulated that EDCs affect humans and animals at environmentally relevant doses. This chapter focuses on data that support and refute the low-dose hypothesis. A case study examining the highly controversial example of bisphenol A and its low-dose effects on the prostate is examined through the lens of endocrinology. Finally, the chapter concludes with a discussion of factors that can influence the ability of a study to detect and interpret low-dose effects appropriately. © 2014 Elsevier Inc. All rights reserved.

  5. Raman micro-spectroscopy analysis of human lens epithelial cells exposed to a low-dose-range of ionizing radiation.

    PubMed

    Allen, Christian Harry; Kumar, Achint; Qutob, Sami; Nyiri, Balazs; Chauhan, Vinita; Murugkar, Sangeeta

    2018-01-09

    Recent findings in populations exposed to ionizing radiation (IR) indicate dose-related lens opacification occurs at much lower doses (<2 Gy) than indicated in radiation protection guidelines. As a result, research efforts are now being directed towards identifying early predictors of lens degeneration resulting in cataractogenesis. In this study, Raman micro-spectroscopy was used to investigate the effects of varying doses of radiation, ranging from 0.01 Gy to 5 Gy, on human lens epithelial (HLE) cells which were chemically fixed 24 h post-irradiation. Raman spectra were acquired from the nucleus and cytoplasm of the HLE cells. Spectra were collected from points in a 3  ×  3 grid pattern and then averaged. The raw spectra were preprocessed and principal component analysis followed by linear discriminant analysis was used to discriminate between dose and control for 0.25, 0.5, 2, and 5 Gy. Using leave-one-out cross-validation accuracies of greater than 74% were attained for each dose/control combination. The ultra-low doses 0.01 and 0.05 Gy were included in an analysis of band intensities for Raman bands found to be significant in the linear discrimination, and an induced repair model survival curve was fit to a band-difference-ratio plot of this data, suggesting HLE cells undergo a nonlinear response to low-doses of IR. A survival curve was also fit to clonogenic assay data done on the irradiated HLE cells, showing a similar nonlinear response.

  6. Raman micro-spectroscopy analysis of human lens epithelial cells exposed to a low-dose-range of ionizing radiation

    NASA Astrophysics Data System (ADS)

    Allen, Christian Harry; Kumar, Achint; Qutob, Sami; Nyiri, Balazs; Chauhan, Vinita; Murugkar, Sangeeta

    2018-01-01

    Recent findings in populations exposed to ionizing radiation (IR) indicate dose-related lens opacification occurs at much lower doses (<2 Gy) than indicated in radiation protection guidelines. As a result, research efforts are now being directed towards identifying early predictors of lens degeneration resulting in cataractogenesis. In this study, Raman micro-spectroscopy was used to investigate the effects of varying doses of radiation, ranging from 0.01 Gy to 5 Gy, on human lens epithelial (HLE) cells which were chemically fixed 24 h post-irradiation. Raman spectra were acquired from the nucleus and cytoplasm of the HLE cells. Spectra were collected from points in a 3  ×  3 grid pattern and then averaged. The raw spectra were preprocessed and principal component analysis followed by linear discriminant analysis was used to discriminate between dose and control for 0.25, 0.5, 2, and 5 Gy. Using leave-one-out cross-validation accuracies of greater than 74% were attained for each dose/control combination. The ultra-low doses 0.01 and 0.05 Gy were included in an analysis of band intensities for Raman bands found to be significant in the linear discrimination, and an induced repair model survival curve was fit to a band-difference-ratio plot of this data, suggesting HLE cells undergo a nonlinear response to low-doses of IR. A survival curve was also fit to clonogenic assay data done on the irradiated HLE cells, showing a similar nonlinear response.

  7. Gestational naltrexone ameliorates fetal ethanol exposures enhancing effect on the postnatal behavioral and neural response to ethanol

    PubMed Central

    Youngentob, Steven L; Kent, Paul F; Youngentob, Lisa M

    2012-01-01

    The association between gestational exposure to ethanol and adolescent ethanol abuse is well established. Recent animal studies support the role of fetal ethanol experience-induced chemosensory plasticity as contributing to this observation. Previously, we established that fetal ethanol exposure, delivered through a dam’s diet throughout gestation, tuned the neural response of the peripheral olfactory system of early postnatal rats to the odor of ethanol. This occurred in conjunction with a loss of responsiveness to other odorants. The instinctive behavioral response to the odor of ethanol was also enhanced. Importantly, there was a significant contributory link between the altered response to the odor of ethanol and increased ethanol avidity when assessed in the same animals. Here, we tested whether the neural and behavioral olfactory plasticity, and their relationship to enhanced ethanol intake, is a result of the mere exposure to ethanol or whether it requires the animal to associate ethanol’s reinforcing properties with its odor attributes. In this later respect, the opioid system is important in the mediation (or modulation) of the reinforcing aspects of ethanol. To block endogenous opiates during prenatal life, pregnant rats received daily intraperitoneal administration of the opiate antagonist naltrexone from gestational day 6–21 jointly with ethanol delivered via diet. Relative to control progeny, we found that gestational exposure to naltrexone ameliorated the enhanced postnatal behavioral response to the odor of ethanol and postnatal drug avidity. Our findings support the proposition that in utero ethanol-induced olfactory plasticity (and its relationship to postnatal intake) requires, at least in part, the associative pairing between ethanol’s odor quality and its reinforcing aspects. We also found suggestive evidence that fetal naltrexone ameliorated the untoward effects of gestational ethanol exposure on the neural response to non

  8. A flexible nanobrush pad for the chemical mechanical planarization of Cu/ultra-low-к materials

    PubMed Central

    2012-01-01

    A new idea of polishing pad called flexible nanobrush pad (FNP) has been proposed for the low down pressure chemical mechanical planarization (CMP) process of Cu/ultra-low-к materials. The FNP was designed with a surface layer of flexible brush-like nanofibers which can ‘actively’ carry nanoscale abrasives in slurry independent of the down pressure. Better planarization performances including high material removal rate, good planarization, good polishing uniformity, and low defectivity are expected in the CMP process under the low down pressure with such kind of pad. The FNP can be made by template-assisted replication or template-based synthesis methods, which will be driven by the development of the preparation technologies for ordered nanostructure arrays. The present work would potentially provide a new solution for the Cu/ultra-low-к CMP process. PMID:23110959

  9. Ultra-low-power wearable biopotential sensor nodes.

    PubMed

    Yazicioglu, R F; Torfs, T; Penders, J; Romero, I; Kim, H; Merken, P; Gyselinckx, B; Yoo, H J; Van Hoof, C

    2009-01-01

    This paper discusses ultra-low-power wireless sensor nodes intended for wearable biopotential monitoring. Specific attention is given to mixed-signal design approaches and their impact on the overall system power dissipation. Examples of trade-offs in power dissipation between analog front-ends and digital signal processing are also given. It is shown how signal filtering can further reduce the internal power consumption of a node. Such power saving approaches are indispensable as real-life tests of custom wireless ECG patches reveal the need for artifact detection and correction. The power consumption of such additional features has to come from power savings elsewhere in the system as the overall power budget cannot increase.

  10. Ultra low-cost, portable smartphone optosensors for mobile point-of-care diagnostics

    NASA Astrophysics Data System (ADS)

    Wang, Li-Ju; Chang, Yu-Chung; Sun, Rongrong; Li, Lei

    2018-02-01

    Smartphone optosensors with integrated optical components make mobile point-of-care (MPoC) diagnostics be done near patients' side. It'll especially have a significant impact on healthcare delivery in rural or remote areas. Current FDA-approved PoC devices achieving clinical level are still at high cost and not affordable in rural hospitals. We present a series of ultra low-cost smartphone optical sensing devices for mobile point-of-care diagnosis. Aiming different targeting analytes and sensing mechanisms, we developed custom required optical components for each smartphone optosensros. These optical devices include spectrum readers, colorimetric readers for microplate, lateral flow device readers, and chemiluminescence readers. By integrating our unique designed optical components into smartphone optosening platform, the anlaytes can be precisely detected. Clinical testing results show the clinical usability of our smartphone optosensors. Ultra low-cost portable smartphone optosensors are affordable for rural/remote doctors.

  11. Changes in the incentive value of food after naltrexone treatment depend on a differential preference for a palatable food in male rats.

    PubMed

    Alvarado-Bañuelos, Mariana; Barrios De Tomasi, Eliana; Juárez, Jorge

    2017-09-01

    Opioid antagonist treatments such as naltrexone (NTX) and naloxone reduce consummatory behavior of palatable food (PF) and other incentives. Meanwhile, a significant increase in alcohol consumption has been observed when it is offered immediately after ending NTX treatment, an effect apparently produced by increased opioidergic activity caused by up-regulation of opioid receptors. On this basis we assessed changes in the consumption of PF after opioid antagonist treatment in rats with different preferences for that food. The preference of male Wistar rats for a PF was classified as low, medium, or high in a baseline period, after which the animals in each preference level were sub-divided into control and experimental groups that received injections of either NTX (2 mg/kg twice per day/6 days) or a saline solution with a space of 8 hours between doses. At the end of pharmacological treatment (PT), subjects were re-exposed to the PF. Increased PF intake was found only in the low-preference group, but the increase was observed in both the experimental and control animals. Also, a decrease in chow intake during PT was observed in all preference groups, while recovery after treatment was noted only in the low-preference rats. The increased intake observed in the low-preference rats after treatment phase suggests that the hypothalamic-pituitary-adrenal axis activation during PT could have enhanced the rewarding characteristics of the sweet food and so facilitated and increased its consumption in the re-exposure period.

  12. Ultra-Low Background Measurements Of Decayed Aerosol Filters

    NASA Astrophysics Data System (ADS)

    Miley, H.

    2009-04-01

    To experimentally evaluate the opportunity to apply ultra-low background measurement methods to samples collected, for instance, by the Comprehensive Test Ban Treaty International Monitoring System (IMS), aerosol samples collected on filter media were measured using HPGe spectrometers of varying low-background technology approaches. In this way, realistic estimates of the impact of low-background methodology can be assessed on the Minimum Detectable Activities obtained in systems such as the IMS. The current measurement requirement of stations in the IMS is 30 microBq per cubic meter of air for 140Ba, or about 106 fissions per daily sample. Importantly, this is for a fresh aerosol filter. Decay varying form 3 days to one week reduce the intrinsic background from radon daughters in the sample. Computational estimates of the improvement factor for these decayed filters for underground-based HPGe in clean shielding materials are orders of magnitude less, even when the decay of the isotopes of interest is included.

  13. Low-Dose Radiation 3D Intraoperative Imaging: How Low Can We Go? An O-Arm, CT Scan, Cadaveric Study.

    PubMed

    Sarwahi, Vishal; Payares, Monica; Wendolowski, Stephen; Maguire, Kathleen; Thornhill, Beverly; Lo, Yungtai; Amaral, Terry D

    2017-11-15

    MINI: The objective of this study was to evaluate the accuracy and reliability of pedicle screw placement using O-Arm at dosages below the manufactured recommended dose. O-Arm at reduced dose showed a 90% accuracy when compared with computed tomography; however, about 30% medial breaches were misclassified. Cadaveric study. The objective was to evaluate O-Arm's ability at low-dose (LD) settings to assess intraoperative screw placement. Accurate placement of pedicle screws is crucial because of proximity to vital structures. Malposition of screws may result in significant morbidity and potential mortality. O-arm provides real-time, intraoperative imaging of patient's anatomy and provides higher accuracy in scoliosis surgeries, avoiding risk to vital structures. We hypothesize using LD or ultra-low doses (ULDs) to obtain intraoperative images allow for accurate assessment of screw placement, both minimizing radiation exposure and preventing screw misplacement. Eight cadavers were instrumented with pedicle screws bilaterally from T1 to S1. Screws were randomly placed using O-arm navigation into three positions: contained within the bone, OUT-anterior/lateral, and OUT-medial. O-arm images were obtained at three dosage settings: LD (kVp120/mAs125-lowest manufacturer recommended), very-low dose (VLD) (kVp120/mAs63), and ULD (kVp120/mAs39). Computed tomography (CT) scan was performed using institution's LD protocol (kVp100/mAs50) and gross dissection to identify screw positions. LD, VLD, ULD, and CT for identifying "IN" screws relative to gross dissection had, a mean (standard deviation) sensitivity of 84.2% (±5.7), specificity of 76.1% (±9.3), and accuracy of 79.9% (±3.1) from all three observers. Across the three observers, the interobserver agreement was 0.67 (0.61-0.72) for LD, 0.74 (0.69-0.79) for VLD, 0.61 (0.56-0.66) for ULD, and 0.79 (0.74-0.84) for CT. Effective doses of radiation (mSV) for LD O-arm scan was 2.16, VLD 1.08, ULD 0.68, and our LD CT protocol was

  14. Comparative analysis of gas and coal-fired power generation in ultra-low emission condition using life cycle assessment (LCA)

    NASA Astrophysics Data System (ADS)

    Yin, Libao; Liao, Yanfen; Liu, Guicai; Liu, Zhichao; Yu, Zhaosheng; Guo, Shaode; Ma, Xiaoqian

    2017-05-01

    Energy consumption and pollutant emission of natural gas combined cycle power-generation (NGCC), liquefied natural gas combined cycle power-generation (LNGCC), natural gas combined heat and power generation (CHP) and ultra-supercritical power generation with ultra-low gas emission (USC) were analyzed using life cycle assessment method, pointing out the development opportunity and superiority of gas power generation in the period of coal-fired unit ultra-low emission transformation. The results show that CO2 emission followed the order: USC>LNGCC>NGCC>CHP the resource depletion coefficient of coal-fired power generation was lower than that of gas power generation, and the coal-fired power generation should be the main part of power generation in China; based on sensitivity analysis, improving the generating efficiency or shortening the transportation distance could effectively improve energy saving and emission reduction, especially for the coal-fired units, and improving the generating efficiency had a great significance for achieving the ultra-low gas emission.

  15. Development of an underground HPGe array facility for ultra low radioactivity measurements

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sala, E.; Kang, W. G.; Kim, Y. D.

    Low Level Counting techniques using low background facilities are continuously under development to increase the possible sensitivity needed for rare physics events experiments. The CUP (Center for Underground Physics) group of IBS is developing, in collaboration with Canberra, a ultra low background instrument composed of two arrays facing each other with 7 HPGe detectors each. The low radioactive background of each detector has been evaluated and improved by the material selection of the detector components. Samples of all the building materials have been provided by the manufacturer and the contaminations had been measured using an optimized low background 100% HPGemore » with a dedicated shielding. The evaluation of the intrinsic background has been performed using MonteCarlo simulations and considering the contribution of each material with the measured contamination. To further reduce the background, the instrument will be placed in the new underground laboratory at YangYang exploiting the 700m mountain coverage and radon-free air supplying system. The array has been designed to perform various Ultra Low background measurements; the sensitivity we are expecting will allow not only low level measurements of Ra and Th contaminations in Copper or other usually pure materials, but also the search for rare decays. In particular some possible candidates and configurations to detect the 0νECEC (for example {sup 106}Cd and {sup 156}Dy) and rare β decays ({sup 96}Zr, {sup 180m}Ta , etc ) are under study.« less

  16. Low-dose vaporized cannabis significantly improves neuropathic pain.

    PubMed

    Wilsey, Barth; Marcotte, Thomas; Deutsch, Reena; Gouaux, Ben; Sakai, Staci; Donaghe, Haylee

    2013-02-01

    We conducted a double-blind, placebo-controlled, crossover study evaluating the analgesic efficacy of vaporized cannabis in subjects, the majority of whom were experiencing neuropathic pain despite traditional treatment. Thirty-nine patients with central and peripheral neuropathic pain underwent a standardized procedure for inhaling medium-dose (3.53%), low-dose (1.29%), or placebo cannabis with the primary outcome being visual analog scale pain intensity. Psychoactive side effects and neuropsychological performance were also evaluated. Mixed-effects regression models demonstrated an analgesic response to vaporized cannabis. There was no significant difference between the 2 active dose groups' results (P > .7). The number needed to treat (NNT) to achieve 30% pain reduction was 3.2 for placebo versus low-dose, 2.9 for placebo versus medium-dose, and 25 for medium- versus low-dose. As these NNTs are comparable to those of traditional neuropathic pain medications, cannabis has analgesic efficacy with the low dose being as effective a pain reliever as the medium dose. Psychoactive effects were minimal and well tolerated, and neuropsychological effects were of limited duration and readily reversible within 1 to 2 hours. Vaporized cannabis, even at low doses, may present an effective option for patients with treatment-resistant neuropathic pain. The analgesia obtained from a low dose of delta-9-tetrahydrocannabinol (1.29%) in patients, most of whom were experiencing neuropathic pain despite conventional treatments, is a clinically significant outcome. In general, the effect sizes on cognitive testing were consistent with this minimal dose. As a result, one might not anticipate a significant impact on daily functioning. Published by Elsevier Inc.

  17. Immediate and long-term effects of opiate antagonists on postictal behaviour following amygdala kindling in the rat.

    PubMed

    Cottrell, G A; Bohus, B

    1987-09-23

    Male Wistar rats implanted with bipolar electrodes in the amygdaloid complex were kindled. Subcutaneous injection of naloxone or naltrexone in low doses--0.12 and 0.24 mg/kg, respectively--dramatically reduced the postictal behavioural depression (BD) at 10 or 60 min. Remarkably, the BD was still reduced one day later. It would appear that the brain mechanisms involved in postictal BD use mu-receptors since BD is quite sensitive to low doses of the preferential antagonists naloxone and naltrexone. The long-term effects, the most novel aspect of these studies, are probably related to immediate effects but could be produced through slow genomic processes or alteration of the response to endogenously released enkephalins.

  18. Dose-effect relationships, epidemiological analysis and the derivation of low dose risk.

    PubMed

    Leenhouts, H P; Chadwick, K H

    2011-03-01

    This paper expands on our recent comments in a letter to this journal about the analysis of epidemiological studies and the determination of low dose RBE of low LET radiation (Chadwick and Leenhouts 2009 J. Radiol. Prot. 29 445-7). Using the assumption that radiation induced cancer arises from a somatic mutation (Chadwick and Leenhouts 2011 J. Radiol. Prot. 31 41-8) a model equation is derived to describe cancer induction as a function of dose. The model is described briefly, evidence is provided in support of it, and it is applied to a set of experimental animal data. The results are compared with a linear fit to the data as has often been done in epidemiological studies. The article presents arguments to support several related messages which are relevant to epidemiological analysis, the derivation of low dose risk and the weighting factor of sparsely ionising radiations. The messages are: (a) cancer incidence following acute exposure should, in principle, be fitted to a linear-quadratic curve with cell killing using all the data available; (b) the acute data are dominated by the quadratic component of dose; (c) the linear fit of any acute data will essentially be dependent on the quadratic component and will be unrelated to the effectiveness of the radiation at low doses; consequently, (d) the method used by ICRP to derive low dose risk from the atomic bomb survivor data means that it is unrelated to the effectiveness of the hard gamma radiation at low radiation doses; (e) the low dose risk value should, therefore, not be used as if it were representative for hard gamma rays to argue for an increased weighting factor for tritium and soft x-rays even though there are mechanistic reasons to expect this; (f) epidemiological studies of chronically exposed populations supported by appropriate cellular radiobiological studies have the best chance of revealing different RBE values for different sparsely ionising radiations.

  19. Assessment of dose and DNA damages in individuals exposed to low dose and low dose rate ionizing radiations during computed tomography imaging.

    PubMed

    Kanagaraj, Karthik; Abdul Syed Basheerudeen, Safa; Tamizh Selvan, G; Jose, M T; Ozhimuthu, Annalakshmi; Panneer Selvam, S; Pattan, Sudha; Perumal, Venkatachalam

    2015-08-01

    Computed tomography (CT) is a frequently used imaging modality that contributes to a tenfold increase in radiation exposure to the public when compared to other medical imaging modalities. The use of radiation for therapeutic need is always rationalized on the basis of risk versus benefit thereby increasing concerns on the dose received by patients undergoing CT imaging. Therefore, it was of interest to us to investigate the effects of low dose and low dose-rate X-irradiation in patients who underwent CT imaging by recording the doses received by the eye, forehead and thyroid, and to study the levels of damages in the lymphocytes in vivo. Lithium manganese borate doped with terbium (LMB:Tb) thermo luminescence dosimeters (TLD) were used to record the doses in the patient's (n = 27) eye, forehead, and thyroid and compared with the dose length product (DLP) values. The in vivo DNA damages measured were compared before and after CT imaging using chromosomal aberration (CA) and micronucleus (MN) assays. The overall measured organ dose ranged between 2 ± 0.29 and 520 ± 41.63 mGy for the eye, 0.84 ± 0.29 and 210 ± 20.50 mGy for the forehead, and 1.79 ± 0.43 and 185 ± 0.70 mGy for the thyroid. The in vivo damages measured from the blood lymphocytes of the subjects showed an extremely significant (p < 0.0001) increase in CA frequency and significant (p < 0.001) increase in MN frequency after exposure, compared to before exposure. The results suggest that CT imaging delivers a considerable amount of radiation dose to the eye, forehead, and thyroid, and the observed increase in the CA and MN frequencies show low dose radiation effects calling for protective regulatory measures to increase patient's safety. This study is the first attempt to indicate the trend of doses received by the patient's eye, forehead and thyroid and measured directly in contrast to earlier values obtained by extrapolation from phantoms, and to assess the in vivo low dose effects in an Indian

  20. Ultra-low profile Ovation device: is it the definitive solution for EVAR?

    PubMed

    de Donato, G; Setacci, F; Sirignano, P; Galzerano, G; Borrelli, M P; di Marzo, L; Setacci, C

    2014-02-01

    When Juan Parodi implanted an endograft in a human body for the first time on September 7, 1990 in Buenos Aires, Argentina, the delivery system of the handmade device was primitive, extremely rigid, and had a bulky profile of 27 French (F). Since then, stent-graft technology has evolved rapidly, limitations of earlier-generation devices have been overtaken, and endovascular aneurysm repair (EVAR) eligibility has increased enormously. Nevertheless (still) challenging aortoiliac anatomy such as short and complex proximal aortic neck seal zones and narrow access vessels are responsible for EVAR ineligibility in up to 50% of cases. The Ovation Prime abdominal stent-graft system (TriVascular, Inc., Santa Rosa, CA, USA) is a trimodular device designed with the aortic body delivered via a flexible, hydrophilic-coated, ultra-low profile catheter (14-F outer diameter - OD). The aortic body is provided with a suprarenal nitinol stent with anchors that provide active fixation, while a network of rings and channels that are inflated with a low-viscosity radiopaque polymer during stent-graft deployment, provides effective sealing. The previous EVAR technology aimed to both anchor and seal using stents combined with fabric, with neither optimized for their roles and each forced to compete for the same space within their delivery catheters, which inevitably led to larger profile of the delivery system. The technical revolution of the Ovation endograft includes the idea to truly uncouple the stages of stent-graft fixation and seal during the procedure. In the Ovation endograft platform, stent and fabric are not competing the same space within the delivery system and an ultra-low profile delivery can be achieved without compromise. With such a low-profile delivery catheter, approximately 90% of men and 70% of women with abdominal aortic aneurysm have access vessel diameters considered fit for endovascular repair. The aim of this review paper was to analyze the main properties of

  1. Low Dose Vaporized Cannabis Significantly Improves Neuropathic Pain

    PubMed Central

    Wilsey, Barth; Marcotte, Thomas D.; Deutsch, Reena; Gouaux, Ben; Sakai, Staci; Donaghe, Haylee

    2013-01-01

    We conducted a double-blind, placebo-controlled, crossover study evaluating the analgesic efficacy of vaporized cannabis in subjects, the majority of whom were experiencing neuropathic pain despite traditional treatment. Thirty-nine patients with central and peripheral neuropathic pain underwent a standardized procedure for inhaling either medium dose (3.53%), low dose (1.29%), or placebo cannabis with the primary outcome being VAS pain intensity. Psychoactive side-effects, and neuropsychological performance were also evaluated. Mixed effects regression models demonstrated an analgesic response to vaporized cannabis. There was no significant difference between the two active dose groups’ results (p>0.7). The number needed to treat (NNT) to achieve 30% pain reduction was 3.2 for placebo vs. low dose, 2.9 for placebo vs. medium dose, and 25 for medium vs. low dose. As these NNT are comparable to those of traditional neuropathic pain medications, cannabis has analgesic efficacy with the low dose being, for all intents and purposes, as effective a pain reliever as the medium dose. Psychoactive effects were minimal and well-tolerated, and neuropsychological effects were of limited duration and readily reversible within 1–2 hours. Vaporized cannabis, even at low doses, may present an effective option for patients with treatment-resistant neuropathic pain. PMID:23237736

  2. Comparison of dehydroepiandrosterone (DHEA) and pregnanolone with existing pharmacotherapies for alcohol abuse on ethanol- and food-maintained responding in male rats

    PubMed Central

    Hulin, Mary W.; Lawrence, Michelle N.; Amato, Russell J.; Weed, Peter F.; Winsauer, Peter J.

    2015-01-01

    acamprosate under that schedule. Experiment 2 showed that ethanol intake was relatively independent of the density of reinforcement in the food-maintained component, and Experiment 3 showed that naltrexone was the most effective drug at the doses tested when the density for food reinforcement was low and maintained under a variable-interval schedule. PMID:25620274

  3. Low dose irradiation facilitates hepatocellular carcinoma genesis involving HULC.

    PubMed

    Li, Yuan; Ge, Chang; Feng, Guoxing; Xiao, Huiwen; Dong, Jiali; Zhu, Changchun; Jiang, Mian; Cui, Ming; Fan, Saijun

    2018-03-24

    Irradiation exposure positive correlates with tumor formation, such as breast cancer and lung cancer. However, whether low dose irradiation induces hepatocarcinogenesis and the underlying mechanism remain poorly defined. In the present study, we reported that low dose irradiation facilitated the proliferation of hepatocyte through up-regulating HULC in vitro and in vivo. Low dose irradiation exposure elevated HULC expression level in hepatocyte. Deletion of heightened HULC erased the cells growth accelerated following low dose irradiation exposure. CDKN1, the neighbor gene of HULC, was down-regulated by overexpression of HULC following low dose irradiation exposure via complementary base pairing, resulting in promoting cell cycle process. Thus, our findings provide new insights into the mechanism of low dose irradiation-induced hepatocarcinogenesis through HULC/CDKN1 signaling, and shed light on the potential risk of low dose irradiation for the development of hepatocellular carcinoma in pre-clinical settings. © 2018 Wiley Periodicals, Inc.

  4. A novel ultrafast-low-dose computed tomography protocol allows concomitant coronary artery evaluation and lung cancer screening.

    PubMed

    Gaudio, Carlo; Petriello, Gennaro; Pelliccia, Francesco; Tanzilli, Alessandra; Bandiera, Alberto; Tanzilli, Gaetano; Barillà, Francesco; Paravati, Vincenzo; Pellegrini, Massimo; Mangieri, Enrico; Barillari, Paolo

    2018-05-08

    Cardiac computed tomography (CT) is often performed in patients who are at high risk for lung cancer in whom screening is currently recommended. We tested diagnostic ability and radiation exposure of a novel ultra-low-dose CT protocol that allows concomitant coronary artery evaluation and lung screening. We studied 30 current or former heavy smoker subjects with suspected or known coronary artery disease who underwent CT assessment of both coronary arteries and thoracic area (Revolution CT, General Electric). A new ultrafast-low-dose single protocol was used for ECG-gated helical acquisition of the heart and the whole chest. A single IV iodine bolus (70-90 ml) was used. All patients with CT evidence of coronary stenosis underwent also invasive coronary angiography. All the coronary segments were assessable in 28/30 (93%) patients. Only 8 coronary segments were not assessable in 2 patients due to motion artefacts (assessability: 98%; 477/485 segments). In the assessable segments, 20/21 significant stenoses (> 70% reduction of vessel diameter) were correctly diagnosed. Pulmonary nodules were detected in 5 patients, thus requiring to schedule follow-up surveillance CT thorax. Effective dose was 1.3 ± 0.9 mSv (range: 0.8-3.2 mSv). Noteworthy, no contrast or radiation dose increment was required with the new protocol as compared to conventional coronary CT protocol. The novel ultrafast-low-dose CT protocol allows lung cancer screening at time of coronary artery evaluation. The new approach might enhance the cost-effectiveness of coronary CT in heavy smokers with suspected or known coronary artery disease.

  5. Co-relationship between sexual dysfunction and high-risk sexual behavior in patients receiving buprenorphine and naltrexone maintenance therapy for opioid dependence.

    PubMed

    Ramdurg, Santosh; Ambekar, Atul; Lal, Rakesh

    2015-01-01

    People suffering from substance dependence suffer from various sexual dysfunctions and are at risk for indulging in various high-risk sexual behaviors and thus are vulnerable to acquire various infections such as HIV/AIDS and other sexually transmitted infections. The aim of the study was to evaluate the correlation between sexual dysfunction and high-risk sexual behavior in opioid-dependent men receiving buprenorphine and naltrexone maintenance therapy. Semi-structured questionnaire, brief male sexual functioning inventory and HIV-risk taking behavior scale was administered to a sample of 60 sexually active men, receiving buprenorphine (n = 30) and naltrexone (n = 30) maintenance therapy for opioid dependence. The main outcomes are correlation between severity of sexual dysfunction and HIV-risk taking behavior. The study results showed 83% of the men on buprenorphine and 90% on naltrexone reported at least one of the sexual dysfunction symptoms. There was a negative correlation between sexual dysfunction and HIV-risk taking behavior that suggest severe the dysfunction, higher the risk taking behavior. Significant correlation was present with overall sexual dysfunction and HIV-risk taking behavior (P = 0.028 and in naltrexone receiving group premature ejaculation versus HIV-risk taking behavior however, (P = 0.022, P < 0.05) there were no significant differences among both the groups except above findings. Conclusion was treatment is associated with sexual dysfunctions and HIV-risk taking behavior, which has clinical implication. Future research should explore this further using biochemical analyses.

  6. Co-relationship between sexual dysfunction and high-risk sexual behavior in patients receiving buprenorphine and naltrexone maintenance therapy for opioid dependence

    PubMed Central

    Ramdurg, Santosh; Ambekar, Atul; Lal, Rakesh

    2015-01-01

    Introduction: People suffering from substance dependence suffer from various sexual dysfunctions and are at risk for indulging in various high-risk sexual behaviors and thus are vulnerable to acquire various infections such as HIV/AIDS and other sexually transmitted infections. AIM: The aim of the study was to evaluate the correlation between sexual dysfunction and high-risk sexual behavior in opioid-dependent men receiving buprenorphine and naltrexone maintenance therapy. Materials and Methods: Semi-structured questionnaire, brief male sexual functioning inventory and HIV-risk taking behavior scale was administered to a sample of 60 sexually active men, receiving buprenorphine (n = 30) and naltrexone (n = 30) maintenance therapy for opioid dependence. Results: The main outcomes are correlation between severity of sexual dysfunction and HIV-risk taking behavior. The study results showed 83% of the men on buprenorphine and 90% on naltrexone reported at least one of the sexual dysfunction symptoms. There was a negative correlation between sexual dysfunction and HIV-risk taking behavior that suggest severe the dysfunction, higher the risk taking behavior. Significant correlation was present with overall sexual dysfunction and HIV-risk taking behavior (P = 0.028 and in naltrexone receiving group premature ejaculation versus HIV-risk taking behavior however, (P = 0.022, P < 0.05) there were no significant differences among both the groups except above findings. Conclusion: Conclusion was treatment is associated with sexual dysfunctions and HIV-risk taking behavior, which has clinical implication. Future research should explore this further using biochemical analyses. PMID:26257480

  7. GaN on Diamond with Ultra-Low Thermal Barrier Resistance

    DTIC Science & Technology

    2016-03-31

    GaN-on-Diamond with Ultra-Low Thermal Barrier Resistance Xing Gu1, Cathy Lee1, Jinqiao Xie1, Edward Beam1, Michael Becker2, Timothy A. Grotjohn2...Bristol BS8 1TL, UK Abstract: We investigated the effective thermal boundary resistance (TBReff) of GaN-on-Diamond interfaces for diamond growth... thermal boundary resistance; TBReff , interfacial layers; high density dielectric Introduction While GaN-based RF transistors, typically on SiC

  8. Divergent short- and long-term effects of acute stress in object recognition memory are mediated by endogenous opioid system activation.

    PubMed

    Nava-Mesa, Mauricio O; Lamprea, Marisol R; Múnera, Alejandro

    2013-11-01

    Acute stress induces short-term object recognition memory impairment and elicits endogenous opioid system activation. The aim of this study was thus to evaluate whether opiate system activation mediates the acute stress-induced object recognition memory changes. Adult male Wistar rats were trained in an object recognition task designed to test both short- and long-term memory. Subjects were randomly assigned to receive an intraperitoneal injection of saline, 1 mg/kg naltrexone or 3 mg/kg naltrexone, four and a half hours before the sample trial. Five minutes after the injection, half the subjects were submitted to movement restraint during four hours while the other half remained in their home cages. Non-stressed subjects receiving saline (control) performed adequately during the short-term memory test, while stressed subjects receiving saline displayed impaired performance. Naltrexone prevented such deleterious effect, in spite of the fact that it had no intrinsic effect on short-term object recognition memory. Stressed subjects receiving saline and non-stressed subjects receiving naltrexone performed adequately during the long-term memory test; however, control subjects as well as stressed subjects receiving a high dose of naltrexone performed poorly. Control subjects' dissociated performance during both memory tests suggests that the short-term memory test induced a retroactive interference effect mediated through light opioid system activation; such effect was prevented either by low dose naltrexone administration or by strongly activating the opioid system through acute stress. Both short-term memory retrieval impairment and long-term memory improvement observed in stressed subjects may have been mediated through strong opioid system activation, since they were prevented by high dose naltrexone administration. Therefore, the activation of the opioid system plays a dual modulating role in object recognition memory. Copyright © 2013 Elsevier Inc. All rights

  9. 'Miracle cure' or 'liquid handcuffs': reporting on naltrexone and methadone in the Australian print media.

    PubMed

    Matthew-Simmons, Francis; Ritter, Alison

    2014-09-01

    The news media is an important source of information regarding new developments in medicine and public health interventions. Previous research has indicated that in many cases, reporting on new treatments can be inaccurate or sensationalist. This paper presents analysis of Australian print media reporting on two treatment options for heroin dependence (naltrexone and methadone). The aim of this study was to quantitatively compare the volume and content of Australian print media reporting on these two treatments, one of which had a long history of use in Australia, and the other which was comparatively newer. The study constituted a quantitative content analysis of a sample of 859 Australian newspaper articles, published over a 10-year period (1997-2007). Each article paragraph was coded for positive outcomes/benefits of treatment, as well as negative outcomes associated with treatment. The analysis revealed that during this period, the Australian print media was significantly more likely to report the potential positive outcomes of naltrexone treatment, compared with the negative outcomes. In contrast, reporting on methadone focused more on the negative outcomes and side effects. The relative frequency by which the benefits of naltrexone were mentioned in this sample of news content is somewhat at odds with the extant efficacy and effectiveness research evidence. The findings suggest that reporting on these treatments in the Australian print media has not been balanced. This type of reporting has potential implications for public attitudes, as well as policy decisions. © 2014 Australasian Professional Society on Alcohol and other Drugs.

  10. Lateral topography for reducing effective dose in low-dose chest CT.

    PubMed

    Bang, Dong-Ho; Lim, Daekeon; Hwang, Wi-Sub; Park, Seong-Hoon; Jeong, Ok-man; Kang, Kyung Wook; Kang, Hohyung

    2013-06-01

    The purposes of this study were to assess radiation exposure during low-dose chest CT by using lateral topography and to compare the lateral topographic findings with findings obtained with anteroposterior topography alone and anteroposterior and lateral topography combined. From November 2011 to February 2012, 210 male subjects were enrolled in the study. Age, weight, and height of the men were recorded. All subjects were placed into one of three subgroups based on the type of topographic image obtained: anteroposterior topography, lateral topography, and both anteroposterior and lateral topography. Imaging was performed with a 128-MDCT scanner. CT, except for topography, was the same for all subjects. A radiologist analyzed each image, recorded scan length, checked for any insufficiencies in the FOV, and calculated the effective radiation dose. One-way analysis of variance and multiple comparisons were used to compare the effective radiation exposure and scan length between groups. The mean scan length in the anteroposterior topography group was significantly greater than that of the lateral topography group and the combined anteroposterior and lateral topography group (p < 0.001). The mean effective radiation dose for the lateral topography group (0.735 ± 0.033 mSv) was significantly lower than that for the anteroposterior topography group (0.763 ± 0.038 mSv) and the combined anteroposterior and lateral topography group (0.773 ± 0.038) (p < 0.001). Lateral topographic low-dose CT was associated with a lower effective radiation dose and scan length than either anteroposterior topographic low-dose chest CT or low-dose chest CT with both anteroposterior and lateral topograms.

  11. Effectiveness of indoor ultra-low volume application of Aqua Reslin® Super during an emergency.

    PubMed

    Ordóñez González, José Genaro; Thirion, Jaime; García Orozco, Abel; Rodríguez, Américo D

    2011-06-01

    Indoor ultra-low volume (ULV) applications of Aqua Reslin Super (Permethrin + s-bioallethrin) were carried out using portable Solo Port 423 sprayers in an urban area of Reforma, Chiapas, Mexico. Sprayers were calibrated to discharge a flow rate of 110 ml/min with a dose range of approximately 0.55 to 0.792 mg Al/m3 space. Entomological evaluation, based on 3 cages per house, each containing 15 sugar-fed, 2-4-day-old Aedes aegypti females and placed in hidden locations in 4 randomly selected houses for 15 min, showed 98.8% to 100% mortality. After the spraying, ovitrap data showed no mosquito adults present 4 days after the applications, and only 1 ovitrap out of 60 positive 8 days after the intervention. This evaluation suggests that indoor ULV application can be useful during emergencies after disasters, during dengue outbreaks, or to prevent mosquito population outbreaks before rainy seasons and, therefore, the onset of dengue transmission in Mexican dengue transmission risk areas.

  12. Experiments on Quantum Hall Topological Phases in Ultra Low Temperatures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Du, Rui-Rui

    2015-02-14

    This project is to cool electrons in semiconductors to extremely low temperatures and to study new states of matter formed by low-dimensional electrons (or holes). At such low temperatures (and with an intense magnetic field), electronic behavior differs completely from ordinary ones observed at room temperatures or regular low temperature. Studies of electrons at such low temperatures would open the door for fundamental discoveries in condensed matter physics. Present studies have been focused on topological phases in the fractional quantum Hall effect in GaAs/AlGaAs semiconductor heterostructures, and the newly discovered (by this group) quantum spin Hall effect in InAs/GaSb materials.more » This project consists of the following components: 1) Development of efficient sample cooling techniques and electron thermometry: Our goal is to reach 1 mK electron temperature and reasonable determination of electron temperature; 2) Experiments at ultra-low temperatures: Our goal is to understand the energy scale of competing quantum phases, by measuring the temperature-dependence of transport features. Focus will be placed on such issues as the energy gap of the 5/2 state, and those of 12/5 (and possible 13/5); resistive signature of instability near 1/2 at ultra-low temperatures; 3) Measurement of the 5/2 gaps in the limit of small or large Zeeman energies: Our goal is to gain physics insight of 5/2 state at limiting experimental parameters, especially those properties concerning the spin polarization; 4) Experiments on tuning the electron-electron interaction in a screened quantum Hall system: Our goal is to gain understanding of the formation of paired fractional quantum Hall state as the interaction pseudo-potential is being modified by a nearby screening electron layer; 5) Experiments on the quantized helical edge states under a strong magnetic field and ultralow temperatures: our goal is to investigate both the bulk and edge states in a quantum spin Hall insulator

  13. [The study of the role of the water medium in the mechanism of action of peptides in low and ultra low doses].

    PubMed

    Grigor'ev, E I; Khavinson, V Kh; Malinin, V V; Grigor'ev, A E; Kochnev, I N; Kudriavtseva, T A

    2003-01-01

    The correlation between the structures and conformations of short peptides KE, EW, AEDG and other, their influence on the dynamic properties of water and dose/biologic effect dependencies in a wide range of concentrations were regarded. Their effects on the dynamic properties of water were studied by temperature dependencies (5-45 degrees C) of infrared spectra of the solutions in the near (5180 cm-1) and far (200 cm-1). In vitro biotesting included the determination of the proliferative activity of thymocytes, a bimodal curve with the second maximum were detected at super-low doses (10(-17)-10(-15) mol/l). Authors propose a hypothesis that for superlow concentrations the formation and distance transmission of a signal from ligand to a target cell without the formation of any ligand-receptor complex take place. An active role in this model belongs to water medium acting according to the solution mechanism.

  14. Calibration of an Ultra-Low-Background Proportional Counter for Measuring 37Ar

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Seifert, Allen; Aalseth, Craig E.; Bonicalzi, Ricco

    Abstract. An ultra-low-background proportional counter (ULBPC) design has been developed at Pacific Northwest National Laboratory (PNNL) using clean materials, primarily electrochemically-purified copper. This detector, along with an ultra-low-background counting system (ULBCS), was developed to complement a new shallow underground laboratory (30 meters water-equivalent) constructed at PNNL. The ULBCS design includes passive neutron and gamma shielding, along with an active cosmic-veto system. This system provides a capability for making ultra-sensitive measurements to support applications like age-dating soil hydrocarbons with 14C/3H, age-dating of groundwater with 39Ar, and soil-gas assay for 37Ar to support On-Site Inspection (OSI). On-Site Inspection is a key componentmore » of the verification regime for the Comprehensive Nuclear-Test-Ban Treaty (CTBT). Measurements of radionuclides created by an underground nuclear explosion are valuable signatures of a Treaty violation. For OSI, the 35-day half-life of 37Ar, produced from neutron interactions with calcium in soil, provides both high specific activity and sufficient time for inspection before decay limits sensitivity. This work describes the calibration techniques and analysis methods developed to enable quantitative measurements of 37Ar samples over a broad range of pressures. These efforts, along with parallel work in progress on gas chemistry separation, are expected to provide a significant new capability for 37Ar soil gas background studies.« less

  15. 100 nm AlSb/InAs HEMT for ultra-low-power consumption, low-noise applications.

    PubMed

    Gardès, Cyrille; Bagumako, Sonia; Desplanque, Ludovic; Wichmann, Nicolas; Bollaert, Sylvain; Danneville, François; Wallart, Xavier; Roelens, Yannick

    2014-01-01

    We report on high frequency (HF) and noise performances of AlSb/InAs high electron mobility transistor (HEMT) with 100 nm gate length at room temperature in low-power regime. Extrinsic cut-off frequencies fT/f max of 100/125 GHz together with minimum noise figure NF(min) = 0.5 dB and associated gain G(ass) = 12 dB at 12 GHz have been obtained at drain bias of only 80 mV, corresponding to 4 mW/mm DC power dissipation. This demonstrates the great ability of AlSb/InAs HEMT for high-frequency operation combined with low-noise performances in ultra-low-power regime.

  16. Development of UItra-Low Temperature Motor Controllers: Ultra Low Temperatures Evaluation and Characterization of Semiconductor Technologies For The Next Generation Space Telescope

    NASA Technical Reports Server (NTRS)

    Elbuluk, Malik E.

    2003-01-01

    Electronics designed for low temperature operation will result in more efficient systems than room temperature. This improvement is a result of better electronic, electrical, and thermal properties of materials at low temperatures. In particular, the performance of certain semiconductor devices improves with decreasing temperature down to ultra-low temperature (-273 'C). The Low Temperature Electronics Program at the NASA Glenn Research Center focuses on research and development of electrical components and systems suitable for applications in deep space missions. Research is being conducted on devices and systems for use down to liquid helium temperatures (-273 'C). Some of the components that are being characterized include semiconductor switching devices, resistors, magnetics, and capacitors. The work performed this summer has focused on the evaluation of silicon-, silicon-germanium- and gallium-Arsenide-based (GaAs) bipolar, MOS and CMOS discrete components and integrated circuits (ICs), from room temperature (23 'C) down to ultra low temperatures (-263 'C).

  17. Opioid growth factor and low-dose naltrexone impair central nervous system infiltration by CD4 + T lymphocytes in established experimental autoimmune encephalomyelitis, a model of multiple sclerosis.

    PubMed

    Hammer, Leslie A; Waldner, Hanspeter; Zagon, Ian S; McLaughlin, Patricia J

    2016-01-01

    Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS), characterized by infiltrating myelin-reactive T lymphocytes and demyelinating lesions. Experimental autoimmune encephalomyelitis (EAE) is the animal model widely utilized to study MS. EAE is mediated by CD4(+) T cells and can be induced in EAE-susceptible mice through immunization with a myelin antigen, such as proteolipid protein 139-151 (PLP139-151) in SJL mice. In this PLP-induced EAE model, autoreactive CD4(+) T cells migrate from peripheral tissues into the CNS where they are reactivated resulting in CNS damage. Th1 and Th17 cells produce the pro-inflammatory cytokines IFNγ and IL-17, respectively, that have been shown to have pathogenic roles in EAE and MS. Anti-inflammatory Th2, IL-4 secreting cells, have been indicated to inhibit EAE exacerbation. However, given the inflammatory environment of EAE, Th2 effector cells are outnumbered by Th1/Th17 cells. Regulatory CD4(+) T cells suppress immune reactions and have been demonstrated to be dysfunctional in MS patients. Opioid growth factor (OGF), chemically termed [Met(5)]-enkephalin, is a negative growth factor that interacts with the OGF receptor. The OGF-OGFr axis can be activated through exogenous administration of OGF or a low dosage of naltrexone (LDN), an opioid antagonist. We have previously demonstrated that modulation of the OGF-OGFr axis results in alleviation from relapse-remitting EAE, and that CNS-infiltrating CD3(+) T cells are diminished with exogenous OGF or intermittent blockade with LDN administration. In this paper, we aimed to determine whether OGF or LDN alter the Th effector responses of CD4(+) T lymphocytes within the CNS in established EAE. We report in these studies that the numbers of CD4(+) T lymphocytes in the CNS of EAE mice are decreased following treatment with OGF for five days but not LDN. However, modulation of the OGF-OGFr axis did not result in changes to CD4(+) Th effector cell responses

  18. Low-dose intradermal and intramuscular vaccination against hepatitis B.

    PubMed

    Bryan, J P; Sjogren, M H; Perine, P L; Legters, L J

    1992-03-01

    Hepatitis B and its sequelae are global problems preventable by immunization. Expense limits the use of hepatitis B vaccines, but low-dose intradermal immunization has been evaluated as a cost-saving strategy in numerous studies. With few exceptions, low-dose intradermal plasma-derived vaccines have elicited protective levels of antibody in 82%-100% of young healthy adults--a proportion similar to that noted with full-dose regimens; peak levels of antibody to hepatitis B surface antigen (HBsAg) are lower with reduced doses, however. Although children respond well to low-dose intradermal immunization, this procedure is technically difficult in neonates and should not be used for those born to HBsAg-positive mothers. For persons at high risk, antibody to HBsAg must be assessed after immunization to determine the need for a booster dose. A fourth dose 1-2 years after the initial series substantially increases antibody concentrations. In low intradermal doses, recombinant vaccine elicits lower rates of seroconversion than plasma-derived vaccine. However, low intramuscular doses of recombinant vaccine give favorable results. In short, low-dose intradermal or intramuscular immunization offers protection against hepatitis B at significant savings and may be useful for mass immunization of populations at high risk.

  19. Accuracy of lung nodule volumetry in low-dose CT with iterative reconstruction: an anthropomorphic thoracic phantom study

    PubMed Central

    Doo, K W; Yong, H S; Woo, O H; Lee, K Y; Oh, Y-W

    2014-01-01

    Objective: The purpose of this study was to assess accuracy of lung nodule volumetry in low-dose CT with application of iterative reconstruction (IR) according to nodule size, nodule density and CT tube currents, using artificial lung nodules within an anthropomorphic thoracic phantom. Methods: Eight artificial nodules (four diameters: 5, 8, 10 and 12 mm; two CT densities: −630 HU that represents ground-glass nodule and +100 HU that represents solid nodule) were randomly placed inside a thoracic phantom. Scans were performed with tube current–time product to 10, 20, 30 and 50 mAs. Images were reconstructed with IR and filtered back projection (FBP). We compared volume estimates to a reference standard and calculated the absolute percentage error (APE). Results: The APE of all nodules was significantly lower when IR was used than with FBP (7.5 ± 4.7% compared with 9.0 ±6.9%; p < 0.001). The effect of IR was more pronounced for smaller nodules (p < 0.001). IR showed a significantly lower APE than FBP in ground-glass nodules (p < 0.0001), and the difference was more pronounced at the lowest tube current (11.8 ± 5.9% compared with 21.3 ± 6.1%; p < 0.0001). The effect of IR was most pronounced for ground-glass nodules in the lowest CT tube current. Conclusion: Lung nodule volumetry in low-dose CT by application of IR showed reliable accuracy in a phantom study. Lung nodule volumetry can be reliably applicable to all lung nodules including small, ground-glass nodules even in ultra-low-dose CT with application of IR. Advances in knowledge: IR significantly improved the accuracy of lung nodule volumetry compared with FBP particularly for ground-glass (−630 HU) nodules. Volumetry in low-dose CT can be utilized in patient with lung nodule work-up, and IR has benefit for small, ground-glass lung nodules in low-dose CT. PMID:25026866

  20. Ultra-low-dose estriol and Lactobacillus acidophilus vaginal tablets (Gynoflor(®)) for vaginal atrophy in postmenopausal breast cancer patients on aromatase inhibitors: pharmacokinetic, safety, and efficacy phase I clinical study.

    PubMed

    Donders, Gilbert; Neven, Patrick; Moegele, Maximilian; Lintermans, Anneleen; Bellen, Gert; Prasauskas, Valdas; Grob, Philipp; Ortmann, Olaf; Buchholz, Stefan

    2014-06-01

    Phase I pharmacokinetic (PK) study assessed circulating estrogens in breast cancer (BC) patients on a non-steroidal aromatase inhibitor (NSAI) with vaginal atrophy using vaginal ultra-low-dose 0.03 mg estriol (E3) and Lactobacillus combination vaginal tablets (Gynoflor(®)). 16 women on NSAI with severe vaginal atrophy applied a daily vaginal tablet of Gynoflor(®) for 28 days followed by a maintenance therapy of 3 tablets weekly for 8 weeks. Primary outcomes were serum concentrations and PK of E3, estradiol (E2), and estrone (E1) using highly sensitive gas chromatography-mass spectrometry. Secondary outcomes were clinical measures for efficacy and side effects; microscopic changes in vaginal epithelium and microflora; and changes in serum FSH, LH, and sex hormone-binding globulin. Compared with baseline, serum E1 and E2 did not increase in any of the women at any time following vaginal application. Serum E3 transiently increased after the first application in 15 of 16 women, with a maximum of 168 pg/ml 2-3 h post-insertion. After 4 weeks, serum E3 was slightly increased in 8 women with a maximum of 44 pg/ml. The vaginal atrophy resolved or improved in all women. The product was well tolerated, and discontinuation of therapy was not observed. The low-dose 0.03 mg E3 and Lactobacillus acidophilus vaginal tablets application in postmenopausal BC patients during AI treatment suffering from vaginal atrophy lead to small and transient increases in serum E3, but not E1 or E2, and therefore can be considered as safe and efficacious for treatment of atrophic vaginitis in BC patients taking NSAIs.

  1. Low Dose MDCT with Tube Current Modulation: Role in Detection of Urolithiasis and Patient Effective Dose Reduction

    PubMed Central

    Kakkar, Chandan; Sripathi, Smiti; Parakh, Anushri; Shrivastav, Rajendra

    2016-01-01

    Introduction Urolithiasis is one of the major, recurring problem in young individuals and CT being the commonest diagnostic modality used. In order to reduce the radiation dose to the patient who are young and as stone formation is a recurring process; one of the simplest way would be, low dose CT along with tube current modulation. Aim Aim of this study was to compare the sensitivity and specificity of low dose (70mAs) with standard dose (250mAs) protocol in detecting urolithiasis and to define the tube current and mean effective patient dose by these protocols. Materials and Methods A prospective study was conducted in 200 patients over a period of 2 years with acute flank pain presentation. CT was performed in 100 cases with standard dose and another 100 with low dose protocol using tube current modulation. Sensitivity and specificity for calculus detection, percentage reduction of dose and tube current with low dose protocol was calculated. Results Urolithiasis was detected in 138 patients, 67 were examined by high dose and 71 were by low dose protocol. Sensitivity and Specificity of low dose protocol was 97.1% and 96.4% with similar results found in high BMI patients. Tube current modulation resulted in reduction of effective tube current by 12.17%. The mean effective patient dose for standard dose was 10.33 mSv whereas 2.92 mSv for low dose with 51.13–53.8% reduction in low dose protocol. Conclusion The study has reinforced that low-dose CT with tube current modulation is appropriate for diagnosis of urolithiasis with significant reduction in tube current and patient effective dose. PMID:27437322

  2. Low Dose MDCT with Tube Current Modulation: Role in Detection of Urolithiasis and Patient Effective Dose Reduction.

    PubMed

    Koteshwar, Prakashini; Kakkar, Chandan; Sripathi, Smiti; Parakh, Anushri; Shrivastav, Rajendra

    2016-05-01

    Urolithiasis is one of the major, recurring problem in young individuals and CT being the commonest diagnostic modality used. In order to reduce the radiation dose to the patient who are young and as stone formation is a recurring process; one of the simplest way would be, low dose CT along with tube current modulation. Aim of this study was to compare the sensitivity and specificity of low dose (70mAs) with standard dose (250mAs) protocol in detecting urolithiasis and to define the tube current and mean effective patient dose by these protocols. A prospective study was conducted in 200 patients over a period of 2 years with acute flank pain presentation. CT was performed in 100 cases with standard dose and another 100 with low dose protocol using tube current modulation. Sensitivity and specificity for calculus detection, percentage reduction of dose and tube current with low dose protocol was calculated. Urolithiasis was detected in 138 patients, 67 were examined by high dose and 71 were by low dose protocol. Sensitivity and Specificity of low dose protocol was 97.1% and 96.4% with similar results found in high BMI patients. Tube current modulation resulted in reduction of effective tube current by 12.17%. The mean effective patient dose for standard dose was 10.33 mSv whereas 2.92 mSv for low dose with 51.13-53.8% reduction in low dose protocol. The study has reinforced that low-dose CT with tube current modulation is appropriate for diagnosis of urolithiasis with significant reduction in tube current and patient effective dose.

  3. Systemic effects of low-dose dopamine during administration of cytarabine.

    PubMed

    Connelly, James; Benani, Dina J; Newman, Matthew; Burton, Bradley; Crow, Jessica; Levis, Mark

    2017-09-01

    Purpose Low-dose dopamine has been utilized to improve renal blood flow, urine output, and reduce drug-induced nephrotoxicity. The purpose of this study was to assess changes in renal function, cardiovascular adverse events, and neurologic toxicity in patients receiving cytarabine with or without low-dose dopamine. Methods A retrospective, single-center, cohort study of patients receiving cytarabine at 667 mg/m 2 /dose or greater, with or without dopamine at ≤5 mcg/kg/min. Cohorts were based upon initiation or absence of low-dose dopamine; cytarabine only, cytarabine + pre- and day of low-dose dopamine, and cytarabine + post-low-dose dopamine. Renal outcomes (urine output, serum creatinine, and creatinine clearance) were compared with baseline and between cohorts. Safety endpoints (arrhythmias, tachycardia, and neurotoxicity) were compared between cohorts based on low-dose dopamine exposure. Results There was no difference in urine output from baseline in all cohorts. Comparing cytarabine only and pre- and day of low-dose dopamine cohorts, there was no difference in urine output. In those receiving low-dose dopamine, there was no difference in serum creatinine and creatinine clearance from baseline. No arrhythmias were documented during the study period, and there was no difference in the incidence of tachycardia between groups (P = 0.66). Neurotoxicity was reported in three patients who were on low-dose dopamine. Conclusion Though variation existed in individual patients administered low-dose dopamine, the use of low-dose dopamine did not significantly impact renal function in this small sample at a single institution. In addition, low-dose dopamine did not negatively impact cardiovascular function.

  4. Circuit design advances for ultra-low power sensing platforms

    NASA Astrophysics Data System (ADS)

    Wieckowski, Michael; Dreslinski, Ronald G.; Mudge, Trevor; Blaauw, David; Sylvester, Dennis

    2010-04-01

    This paper explores the recent advances in circuit structures and design methodologies that have enabled ultra-low power sensing platforms and opened up a host of new applications. Central to this theme is the development of Near Threshold Computing (NTC) as a viable design space for low power sensing platforms. In this paradigm, the system's supply voltage is approximately equal to the threshold voltage of its transistors. Operating in this "near-threshold" region provides much of the energy savings previously demonstrated for subthreshold operation while offering more favorable performance and variability characteristics. This makes NTC applicable to a broad range of power-constrained computing segments including energy constrained sensing platforms. This paper explores the barriers to the adoption of NTC and describes current work aimed at overcoming these obstacles in the circuit design space.

  5. Limiting CT radiation dose in children with craniosynostosis: phantom study using model-based iterative reconstruction.

    PubMed

    Kaasalainen, Touko; Palmu, Kirsi; Lampinen, Anniina; Reijonen, Vappu; Leikola, Junnu; Kivisaari, Riku; Kortesniemi, Mika

    2015-09-01

    Medical professionals need to exercise particular caution when developing CT scanning protocols for children who require multiple CT studies, such as those with craniosynostosis. To evaluate the utility of ultra-low-dose CT protocols with model-based iterative reconstruction techniques for craniosynostosis imaging. We scanned two pediatric anthropomorphic phantoms with a 64-slice CT scanner using different low-dose protocols for craniosynostosis. We measured organ doses in the head region with metal-oxide-semiconductor field-effect transistor (MOSFET) dosimeters. Numerical simulations served to estimate organ and effective doses. We objectively and subjectively evaluated the quality of images produced by adaptive statistical iterative reconstruction (ASiR) 30%, ASiR 50% and Veo (all by GE Healthcare, Waukesha, WI). Image noise and contrast were determined for different tissues. Mean organ dose with the newborn phantom was decreased up to 83% compared to the routine protocol when using ultra-low-dose scanning settings. Similarly, for the 5-year phantom the greatest radiation dose reduction was 88%. The numerical simulations supported the findings with MOSFET measurements. The image quality remained adequate with Veo reconstruction, even at the lowest dose level. Craniosynostosis CT with model-based iterative reconstruction could be performed with a 20-μSv effective dose, corresponding to the radiation exposure of plain skull radiography, without compromising required image quality.

  6. Naltrexone-sensitive analgesia following exposure of mice to 2450-MHz radiofrequency radiation (RFR)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maillefer, R.H.; Quock, R.M.

    1991-03-11

    This study was conducted to determine whether exposure to RFR might induce sufficient thermal stress to activate endogenous opioid mechanisms and induce analgesia. Male Swiss Webster mice, 20-25 g, were exposed to 10, 15 or 20 mV/cm{sup 2} RFR in a 2,450-MHz waveguide system for 10 min, then tested in the abdominal constriction paradigm. Specific absorption rates (SAR) were 23.7 W/kg at 10 mW/cm{sup 2}, 34.6 W/kg at 15 mW/cm{sup 2} and 45.5 W/kg at 20 mW/cm{sup 2}. Confinement in the exposure chamber alone did not appreciably alter body temperature but did appear to induce a stress-associated analgesia that wasmore » insensitive to the opioid receptor blocker naltrexone. Exposure of confined mice to RFR elevated body temperature and further increased analgesia in SAR-dependent manner. The high-SAR RFR-induced analgesia, but not the hyperthermia, was reduced by naltrexone. These findings suggest that (1) RFR produces SAR-dependent hyperthermia and analgesia and (2) RFR-induced analgesia is mediated by opioid mechanisms while confinement-induced analgesia involves non-opioid mechanisms.« less

  7. Chromatic dispersion effects in ultra-low coherence interferometry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lychagov, V V; Ryabukho, V P

    2015-06-30

    We consider the properties of an interference signal shift from zero-path-difference position in the presence of an uncompensated dispersive layer in one of the interferometer arms. It is experimentally shown that in using an ultra-low coherence light source, the formation of the interference signal is also determined by the group velocity dispersion, which results in a nonlinear dependence of the position of the interference signal on the geometrical thickness of the dispersive layer. The discrepancy in the dispersive layer and compensator refractive indices in the third decimal place is experimentally shown to lead to an interference signal shift that ismore » an order of magnitude greater than the pulse width. (interferometry)« less

  8. Performance study of personal inhalable aerosol samplers at ultra-low wind speeds.

    PubMed

    Sleeth, Darrah K; Vincent, James H

    2012-03-01

    The assessment of personal inhalable aerosol samplers in a controlled laboratory setting has not previously been carried out at the ultra-low wind speed conditions that represent most modern workplaces. There is currently some concern about whether the existing inhalable aerosol convention is appropriate at these low wind speeds and an alternative has been suggested. It was therefore important to assess the performance of the most common personal samplers used to collect the inhalable aerosol fraction, especially those that were designed to match the original curve. The experimental set-up involved use of a hybrid ultra-low speed wind tunnel/calm air chamber and a rotating, heating breathing mannequin to measure the inhalable fraction of aerosol exposure. The samplers that were tested included the Institute of Occupational Medicine (IOM), Button, and GSP inhalable samplers as well as the closed-face cassette sampler that has been (and still is) widely used by occupational hygienists in many countries. The results showed that, down to ∼0.2 m s(-1), the samplers matched the current inhalability criterion relatively well but were significantly greater than this at the lowest wind speed tested. Overall, there was a significant effect of wind speed on sampling efficiency, with lower wind speeds clearly associated with an increase in sampling efficiency.

  9. 100 nm AlSb/InAs HEMT for Ultra-Low-Power Consumption, Low-Noise Applications

    PubMed Central

    Bagumako, Sonia; Desplanque, Ludovic; Wichmann, Nicolas; Bollaert, Sylvain; Danneville, François; Wallart, Xavier

    2014-01-01

    We report on high frequency (HF) and noise performances of AlSb/InAs high electron mobility transistor (HEMT) with 100 nm gate length at room temperature in low-power regime. Extrinsic cut-off frequencies f T/f max of 100/125 GHz together with minimum noise figure NFmin = 0.5 dB and associated gain G ass = 12 dB at 12 GHz have been obtained at drain bias of only 80 mV, corresponding to 4 mW/mm DC power dissipation. This demonstrates the great ability of AlSb/InAs HEMT for high-frequency operation combined with low-noise performances in ultra-low-power regime. PMID:24707193

  10. Impulse Excitation Internal Friction Study of Dislocation and Point Defect Interactions in Ultra-Low Carbon Bake-Hardenable Steel

    NASA Astrophysics Data System (ADS)

    Jung, Il-Chan; Kang, Deok-Gu; De Cooman, Bruno C.

    2014-04-01

    The simultaneous presence of interstitial solutes and dislocations in an ultra-low carbon bake-hardenable steel gives rise to two characteristic peaks in the internal friction (IF) spectrum: the dislocation-enhanced Snoek peak and the Snoek-Kê-Köster peak. These IF peaks were used to study the dislocation structure developed by the pre-straining and the static strain aging effect of C during the bake-hardening process. A Ti-stabilized interstitial-free steel was used to ascertain the absence of a γ-peak in the IF spectrum of the deformed ultra-low carbon steel. The analysis of the IF data shows clearly that the bake-hardening effect in ultra-low carbon steel is entirely due to atmosphere formation, with the dislocation segment length being the main parameter affecting the IF peak amplitude. Recovery annealing experiments showed that the rearrangement of the dislocation structure lead to the elimination of the C atmosphere.

  11. Using MOF-74 for Hg{sup 2+} removal from ultra-low concentration aqueous solution

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xiong, Yang Yang; Li, Jian Qiang; Gong, Le Le

    Mercury (Hg{sup 2+}) ions have very high toxicity and widely spread as environmental pollutants. At present, many efforts have been taken to remove the hazardous materials of mercury(II) by adsorption, and it is highly desirable to develop a novel adsorbent with high adsorptive capacities. However it is still a big challenge to remove the ultra-low-concentration mercury ions from water. In this paper, MOF-74-Zn is explored for such function, showing high removal rate of Hg(II) from water without any pretreatment, especially for the ultra-trace Hg(II) ions in the ppb magnitude with the removal rate reaching to 54.48%, 69.71%, 72.26% when themore » initial concentration of Hg(II) is 20ppb, 40ppb, 50ppb, respectively. - Graphical abstract: The absorption of mercury ions on MOF-74-Zn is due to somewhat weak interactions between MOF skeleton that is composed of carboxylate and hydroxy group and Hg2+ ions. - Highlights: • MOF-74-Zn shows high removal rate of Hg(II) from water without any pretreatment. • The MOF-74-Zn has a notable performance at ultra-low concentration of Hg(II). • MOF-74-Zn shows the potential for Hg(II) removal from industrial waste water.« less

  12. Ultra-low-loss and broadband mode converters in Si3N4 technology

    NASA Astrophysics Data System (ADS)

    Mu, Jinfeng; Dijkstra, Meindert; de Goede, Michiel; Yong, Yean-Sheng; García-Blanco, Sonia M.

    2017-02-01

    Si3N4 grown by low pressure chemical vapor deposition (LPCVD) on thermally oxidized silicon wafers is largely utilized for creating integrated photonic devices due to its ultra-low propagation loss and large transparency window (400 nm to 2350 nm). In this paper, an ultra-low-loss and broadband mode converter for monolithic integration of different materials onto the passive Si3N4 photonic technology platform is presented. The mode size converter is constructed with a vertically tapered Si3N4 waveguide that is then buried by a polymer or an Al2O3 waveguide. The influence of the various design parameters on the converter characteristics are investigated. Optimal designs are proposed, in which the thickness of the Si3N4 waveguide is tapered from 200 nm to 40 nm. The calculated losses of the mode converters at 976 nm and 1550 nm wavelengths are well below 0.1 dB for the Si3N4-polymer coupler and below 0.3 dB for the Si3N4-Al2O3 coupler. The preliminary experimental results show good agreement with the design values, indicating that the mode converters can be utilized for the low-loss integration of different materials.

  13. Ultra-low-head hydroelectric technology: A review

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhou, Daqing; Deng, Zhiqun

    In recent years, distributed renewable energy-generation technologies, such as wind and solar, have developed rapidly. Nevertheless, the utilization of ultra-low-head (ULH) water energy (i.e., situations where the hydraulic head is less than 3 m or the water flow is more than 0.5 m/s with zero head) has received little attention. We believe that, through technological innovations and cost reductions, ULH hydropower has the potential to become an attractive, renewable, and sustainable resource. This paper investigates potential sites for ULH energy resources, the selection of relevant turbines and generators, simplification of civil works, and project costs. This review introduces the currentmore » achievements on ULH hydroelectric technology to stimulate discussions and participation of stakeholders to develop related technologies for further expanding its utilization as an important form of renewable energy.« less

  14. High-dose Versus Low-dose Tranexamic Acid to Reduce Transfusion Requirements in Pediatric Scoliosis Surgery.

    PubMed

    Johnson, Daniel J; Johnson, Christine C; Goobie, Susan M; Nami, Nina; Wetzler, Joshua A; Sponseller, Paul D; Frank, Steven M

    2017-12-01

    Our objective was to quantify blood loss and transfusion requirements for high-dose and low-dose tranexamic acid (TXA) dosing regimens in pediatric patients undergoing spinal fusion for correction of idiopathic scoliosis. Previous investigators have established the efficacy of TXA in pediatric scoliosis surgery; however, the dosing regimens vary widely and the optimal dose has not been established. We retrospectively analyzed electronic medical records for 116 patients who underwent spinal fusion surgery for idiopathic scoliosis by a single surgeon and were treated with TXA. In total, 72 patients received a 10 mg/kg loading dose with a 1 mg/kg/h maintenance dose (low-dose) and 44 patients received 50 mg/kg loading dose with a 5 mg/kg/h maintenance dose (high-dose). Estimated blood loss and transfusion requirements were compared between dosing groups. Patient characteristics were nearly identical between the 2 groups. Compared with the low-dose TXA group, the high-dose TXA group had decreased estimated blood loss (695 vs. 968 mL, P=0.01), and a decrease in both intraoperative (0.3 vs. 0.9 units, P=0.01) and whole hospitalization (0.4 vs. 1.0 units, P=0.04) red blood cell transfusion requirements. The higher-dose TXA was associated with decreased intraoperative (P=0.01), and whole hospital transfusion (P=0.01) requirements, even after risk-adjustment for potential confounding variables. High-dose TXA is more effective than low-dose TXA in reducing blood loss and transfusion requirements in pediatric idiopathic scoliosis patients undergoing surgery. Level-III, retrospective cohort study.

  15. Investigation of structure, vibrational and NMR spectra of oxycodone and naltrexone: A combined experimental and theoretical study

    NASA Astrophysics Data System (ADS)

    Tavakol, Hossein; Esfandyari, Maryam; Taheri, Salman; Heydari, Akbar

    2011-08-01

    In this work, two important opioid antagonists, naltrexone and oxycodone, were prepared from thebaine and were characterized by IR, 1H NMR and 13C NMR spectroscopy. Moreover, computational NMR and IR parameters were obtained using density functional theory (DFT) at B3LYP/6-311++G** level of theory. Complete NMR and vibrational assignment were carried out using the observed and calculated spectra. The IR frequencies and NMR chemical shifts, determined experimentally, were compared with those obtained theoretically from DFT calculations, showed good agreements. The RMS errors observed between experimental and calculated data for the IR absorptions are 85 and 105 cm -1, for the 1H NMR peaks are 0.87 and 0.17 ppm and for those of 13C NMR are 5.6 and 5.3 ppm, respectively for naltrexone and oxycodone.

  16. Deep learning for low-dose CT

    NASA Astrophysics Data System (ADS)

    Chen, Hu; Zhang, Yi; Zhou, Jiliu; Wang, Ge

    2017-09-01

    Given the potential risk of X-ray radiation to the patient, low-dose CT has attracted a considerable interest in the medical imaging field. Currently, the main stream low-dose CT methods include vendor-specific sinogram domain filtration and iterative reconstruction algorithms, but they need to access raw data whose formats are not transparent to most users. Due to the difficulty of modeling the statistical characteristics in the image domain, the existing methods for directly processing reconstructed images cannot eliminate image noise very well while keeping structural details. Inspired by the idea of deep learning, here we combine the autoencoder, deconvolution network, and shortcut connections into the residual encoder-decoder convolutional neural network (RED-CNN) for low-dose CT imaging. After patch-based training, the proposed RED-CNN achieves a competitive performance relative to the-state-of-art methods. Especially, our method has been favorably evaluated in terms of noise suppression and structural preservation.

  17. Austrian Mirrors: Development of Ultra-Low-Loss Cryogenic Crystalline Coatings (DARPA)

    DTIC Science & Technology

    2016-07-13

    AFRL-AFOSR-UK-TR-2016-0013 Austrian Mirrors: Development of ultra-low- loss cryogenic crystalline coatings (DARPA) Garrett Cole Crystalline Mirror...REPORT DOCUMENTATION PAGE Form ApprovedOMB No . 0704-0188 The public reporting burden for this collection of information is estimated to average 1 hour...that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information   if

  18. Preoperative assessment of pleural adhesion by Four-Dimensional Ultra-Low-Dose Computed Tomography (4D-ULDCT) with Adaptive Iterative Dose Reduction using Three-Dimensional processing (AIDR-3D).

    PubMed

    Hashimoto, Masayuki; Nagatani, Yukihiro; Oshio, Yasuhiko; Nitta, Norihisa; Yamashiro, Tsuneo; Tsukagoshi, Shinsuke; Ushio, Noritoshi; Mayumi, Masayuki; Kimoto, Tatsuya; Igarashi, Tomoyuki; Yoshigoe, Makoto; Iwai, Kyohei; Tanaka, Koki; Sato, Shigetaka; Sonoda, Akinaga; Otani, Hideji; Murata, Kiyoshi; Hanaoka, Jun

    2018-01-01

    To assess the feasibility of Four-Dimensional Ultra-Low-Dose Computed Tomography (4D-ULDCT) for distinguishing pleural aspects with localized pleural adhesion (LPA) from those without. Twenty-seven patients underwent 4D-ULDCT during a single respiration with a 16cm-coverage of the body axis. The presence and severity of LPA was confirmed by their intraoperative thoracoscopic findings. A point on the pleura and a corresponding point on the outer edge of the costal bone were placed in identical axial planes at end-inspiration. The distance of the two points (PCD), traced by automatic tracking functions respectively, was calculated at each respiratory phase. The maximal and average change amounts in PCD (PCD MCA and PCD ACA ) were compared among 110 measurement points (MPs) without LPA, 16MPs with mild LPA and 10MPs with severe LPA in upper lung field cranial to the bronchial bifurcation (ULF), and 150MPs without LPA, 17MPs with mild LPA and 9MPs with severe LPA in lower lung field caudal to the bronchial bifurcation (LLF) using the Mann-Whitney U test. In the LLF, PCD ACA as well as PCD MCA demonstrated a significant difference among non-LPA, mild LPA and severe LPA (18.1±9.2, 12.3±6.2 and 5.0±3.3mm) (p<0.05). Also in the ULF, PCD ACA showed a significant difference among three conditions (9.2±5.5, 5.7±2.8 and 2.2±0.4mm, respectively) (p<0.05), whereas PCD MCA for mild LPA was similar to that for non-LPA (12.3±5.9 and 17.5±11.0mm). Four D-ULDCT could be a useful non-invasive preoperative assessment modality for the detection of the presence or severity of LPA. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Super-low dose endotoxin pre-conditioning exacerbates sepsis mortality.

    PubMed

    Chen, Keqiang; Geng, Shuo; Yuan, Ruoxi; Diao, Na; Upchurch, Zachary; Li, Liwu

    2015-04-01

    Sepsis mortality varies dramatically in individuals of variable immune conditions, with poorly defined mechanisms. This phenomenon complements the hypothesis that innate immunity may adopt rudimentary memory, as demonstrated in vitro with endotoxin priming and tolerance in cultured monocytes. However, previous in vivo studies only examined the protective effect of endotoxin tolerance in the context of sepsis. In sharp contrast, we report herein that pre-conditionings with super-low or low dose endotoxin lipopolysaccharide (LPS) cause strikingly opposite survival outcomes. Mice pre-conditioned with super-low dose LPS experienced severe tissue damage, inflammation, increased bacterial load in circulation, and elevated mortality when they were subjected to cecal-ligation and puncture (CLP). This is in opposite to the well-reported protective phenomenon with CLP mice pre-conditioned with low dose LPS. Mechanistically, we demonstrated that super-low and low dose LPS differentially modulate the formation of neutrophil extracellular trap (NET) in neutrophils. Instead of increased ERK activation and NET formation in neutrophils pre-conditioned with low dose LPS, we observed significantly reduced ERK activation and compromised NET generation in neutrophils pre-conditioned with super-low dose LPS. Collectively, our findings reveal a novel mechanism potentially responsible for the dynamic programming of innate immunity in vivo as it relates to sepsis risks.

  20. Rotatable Small Permanent Magnet Array for Ultra-Low Field Nuclear Magnetic Resonance Instrumentation: A Concept Study.

    PubMed

    Vogel, Michael W; Giorni, Andrea; Vegh, Viktor; Pellicer-Guridi, Ruben; Reutens, David C

    2016-01-01

    We studied the feasibility of generating the variable magnetic fields required for ultra-low field nuclear magnetic resonance relaxometry with dynamically adjustable permanent magnets. Our motivation was to substitute traditional electromagnets by distributed permanent magnets, increasing system portability. The finite element method (COMSOL®) was employed for the numerical study of a small permanent magnet array to calculate achievable magnetic field strength, homogeneity, switching time and magnetic forces. A manually operated prototype was simulated and constructed to validate the numerical approach and to verify the generated magnetic field. A concentric small permanent magnet array can be used to generate strong sample pre-polarisation and variable measurement fields for ultra-low field relaxometry via simple prescribed magnet rotations. Using the array, it is possible to achieve a pre-polarisation field strength above 100 mT and variable measurement fields ranging from 20-50 μT with 200 ppm absolute field homogeneity within a field-of-view of 5 x 5 x 5 cubic centimetres. A dynamic small permanent magnet array can generate multiple highly homogeneous magnetic fields required in ultra-low field nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) instruments. This design can significantly reduce the volume and energy requirements of traditional systems based on electromagnets, improving portability considerably.

  1. Restored low-dose digital breast tomosynthesis: a perception study

    NASA Astrophysics Data System (ADS)

    Borges, Lucas R.; Bakic, Predrag R.; Maidment, Andrew D. A.; Vieira, Marcelo A. C.

    2018-03-01

    This work investigates the perception of noise from restored low-dose digital breast tomosynthesis (DBT) images. First, low-dose DBT projections were generated using a dose reduction simulation algorithm. A dataset of clinical images from the Hospital of the University of Pennsylvania was used for this purpose. Low-dose projections were then denoised with a denoising pipeline developed specifically for DBT images. Denoised and noisy projections were combined to generate images with signal-to-noise ratio comparable to the full-dose images. The quality of restored low-dose and full-dose projections were first compared in terms of an objective no-reference image quality metric previously validated for mammography. In the second analysis, regions of interest (ROIs) were selected from reconstructed full-dose and restored low-dose slices, and were displayed side-by-side on a high-resolution medical display. Five medical physics specialists were asked to choose the image containing less noise and less blur using a 2-AFC experiment. The objective metric shows that, after the proposed image restoration framework was applied, images with as little as 60% of the AEC dose yielded similar quality indices when compared to images acquired with the full-dose. In the 2-AFC experiments results showed that when the denoising framework was used, 30% reduction in dose was possible without any perceived difference in noise or blur. Note that this study evaluated the observers perception to noise and blur and does not claim that the dose of DBT examinations can be reduced with no harm to the detection of cancer. Future work is necessary to make any claims regarding detection, localization and characterization of lesions.

  2. Simultaneous measurement of tritium and radiocarbon by ultra-low-background proportional counting.

    PubMed

    Mace, Emily; Aalseth, Craig; Alexander, Tom; Back, Henning; Day, Anthony; Hoppe, Eric; Keillor, Martin; Moran, Jim; Overman, Cory; Panisko, Mark; Seifert, Allen

    2017-08-01

    Use of ultra-low-background capabilities at Pacific Northwest National Laboratory provide enhanced sensitivity for measurement of low-activity sources of tritium and radiocarbon using proportional counters. Tritium levels are nearly back to pre-nuclear test backgrounds (~2-8 TU in rainwater), which can complicate their dual measurement with radiocarbon due to overlap in the beta decay spectra. We present results of single-isotope proportional counter measurements used to analyze a dual-isotope methane sample synthesized from ~120mg of H 2 O and present sensitivity results. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Simultaneous measurement of tritium and radiocarbon by ultra-low-background proportional counting

    DOE PAGES

    Mace, Emily; Aalseth, Craig; Alexander, Tom; ...

    2016-12-21

    Use of ultra-low-background capabilities at Pacific Northwest National Laboratory provide enhanced sensitivity for measurement of low-activity sources of tritium and radiocarbon using proportional counters. Tritium levels are nearly back to pre-nuclear test backgrounds (~2-8 TU in rainwater), which can complicate their dual measurement with radiocarbon due to overlap in the beta decay spectra. In this paper, we present results of single-isotope proportional counter measurements used to analyze a dual-isotope methane sample synthesized from ~120 mg of H 2O and present sensitivity results.

  4. Super non-linear RRAM with ultra-low power for 3D vertical nano-crossbar arrays.

    PubMed

    Luo, Qing; Xu, Xiaoxin; Liu, Hongtao; Lv, Hangbing; Gong, Tiancheng; Long, Shibing; Liu, Qi; Sun, Haitao; Banerjee, Writam; Li, Ling; Gao, Jianfeng; Lu, Nianduan; Liu, Ming

    2016-08-25

    Vertical crossbar arrays provide a cost-effective approach for high density three-dimensional (3D) integration of resistive random access memory. However, an individual selector device is not allowed to be integrated with the memory cell separately. The development of V-RRAM has impeded the lack of satisfactory self-selective cells. In this study, we have developed a high performance bilayer self-selective device using HfO2 as the memory switching layer and a mixed ionic and electron conductor as the selective layer. The device exhibits high non-linearity (>10(3)) and ultra-low half-select leakage (<0.1 pA). A four layer vertical crossbar array was successfully demonstrated based on the developed self-selective device. High uniformity, ultra-low leakage, sub-nA operation, self-compliance, and excellent read/write disturbance immunity were achieved. The robust array level performance shows attractive potential for low power and high density 3D data storage applications.

  5. Ultra compact 45 GHz CMOS compatible Germanium waveguide photodiode with low dark current.

    PubMed

    DeRose, Christopher T; Trotter, Douglas C; Zortman, William A; Starbuck, Andrew L; Fisher, Moz; Watts, Michael R; Davids, Paul S

    2011-12-05

    We present a compact 1.3 × 4 μm2 Germanium waveguide photodiode, integrated in a CMOS compatible silicon photonics process flow. This photodiode has a best-in-class 3 dB cutoff frequency of 45 GHz, responsivity of 0.8 A/W and dark current of 3 nA. The low intrinsic capacitance of this device may enable the elimination of transimpedance amplifiers in future optical data communication receivers, creating ultra low power consumption optical communications.

  6. Low-dose radiation attenuates chemical mutagenesis in vivo.

    PubMed

    Kakinuma, Shizuko; Yamauchi, Kazumi; Amasaki, Yoshiko; Nishimura, Mayumi; Shimada, Yoshiya

    2009-09-01

    The biological effects of low-dose radiation are not only of social concern but also of scientific interest. The radioadaptive response, which is defined as an increased radioresistance by prior exposure to low-dose radiation, has been extensively studied both in vitro and in vivo. Here we briefly review the radioadaptive response with respect to mutagenesis, survival rate, and carcinogenesis in vivo, and introduce our recent findings of cross adaptation in mouse thymic cells, that is, the suppressive effect of repeated low-dose radiation on mutation induction by the alkylating agent N-ethyl-N-nitrosourea.

  7. Ultra-low loss Si3N4 waveguides with low nonlinearity and high power handling capability.

    PubMed

    Tien, Ming-Chun; Bauters, Jared F; Heck, Martijn J R; Blumenthal, Daniel J; Bowers, John E

    2010-11-08

    We investigate the nonlinearity of ultra-low loss Si3N4-core and SiO2-cladding rectangular waveguides. The nonlinearity is modeled using Maxwell's wave equation with a small amount of refractive index perturbation. Effective n2 is used to describe the third-order nonlinearity, which is linearly proportional to the optical intensity. The effective n2 measured using continuous-wave self-phase modulation shows agreement with the theoretical calculation. The waveguide with 2.8-μm wide and 80-nm thick Si3N4 core has low loss and high power handling capability, with an effective n2 of about 9×10(-16) cm2/W.

  8. Comparison of dehydroepiandrosterone (DHEA) and pregnanolone with existing pharmacotherapies for alcohol abuse on ethanol- and food-maintained responding in male rats.

    PubMed

    Hulin, Mary W; Lawrence, Michelle N; Amato, Russell J; Weed, Peter F; Winsauer, Peter J

    2015-03-01

    acamprosate under that schedule. Experiment 2 showed that ethanol intake was relatively independent of the interval of reinforcement in the food-maintained component, and Experiment 3 showed that naltrexone was the most effective drug at the doses tested when the interval for food reinforcement was low and maintained under a variable-interval schedule. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Ultra-low-loss tapered optical fibers with minimal lengths

    NASA Astrophysics Data System (ADS)

    Nagai, Ryutaro; Aoki, Takao

    2014-11-01

    We design and fabricate ultra-low-loss tapered optical fibers (TOFs) with minimal lengths. We first optimize variations of the torch scan length using the flame-brush method for fabricating TOFs with taper angles that satisfy the adiabaticity criteria. We accordingly fabricate TOFs with optimal shapes and compare their transmission to TOFs with a constant taper angle and TOFs with an exponential shape. The highest transmission measured for TOFs with an optimal shape is in excess of 99.7 % with a total TOF length of only 23 mm, whereas TOFs with a constant taper angle of 2 mrad reach 99.6 % transmission for a 63 mm TOF length.

  10. Ultra low-level measurements of actinides by sector field ICP-MS.

    PubMed

    Pointurier, F; Baglan, N; Hémet, P

    2004-01-01

    In the present work, a double-focusing sector field inductively coupled plasma-mass spectrometer was optimised for ultra trace and isotopic analyses of actinide long-lived isotopes in low concentration solutions of the fgml(-1) to the ngml(-1) range. Sensitivities of about 3GHz/(microgml(-1)), with as low a background as 0.1cps, were obtained for U using a conventional concentric pneumatic nebuliser. Detection limits are below the fg range for 239Pu and 240Pu. With natural U, a precision lower than 0.5% RSD is currently obtained for 235U/238U isotopic ratio at the 200pgml(-1) level.

  11. Comparative treatment and mortality correlates and adverse event profile of implant naltrexone and sublingual buprenorphine.

    PubMed

    Reece, Albert Stuart

    2009-10-01

    There is increasing interest in the use of implantable naltrexone as a new treatment for opiate dependence. This center has been one of the leaders in this form of treatment in Australia and has recently completed a registry-controlled review of our mortality data. As part of the study of the safety profile of this therapy, we were interested to review both the treatment correlates of previously presented mortality data and of adverse events. A total of 255 naltrexone implant therapy (NIT) and 2,518 buprenorphine (BUP) patients were followed for 1,322.22 and 8,030.02 patient-years, respectively. NIT patients had significantly longer days in treatment per episode (mean +/- standard deviation, 238.32 +/- 110.11 vs. 46.96 +/- 109.79), total treatment duration (371.21 +/- 284.64 vs. 162.50 +/- 245.76), and mean treatment times but fewer treatment episodes than BUP (all p < .0001). Serious local tissue reaction or infection each occurred in 1% of 200 NIT episodes. These data show that NIT economizes treatment resources without compromising safety concerns.

  12. Intranasal naltrexone and atipamezole for reversal of white-tailed deer immobilized with carfentanil and medetomidine

    PubMed Central

    Shury, Todd K.; Caulkett, Nigel A.; Woodbury, Murray R.

    2010-01-01

    Carfentanil and medetomidine were used to immobilize 8 captive female white-tailed deer (Odocoileus virginianus) using mean dosages [± standard deviation (s)] of 14.2 ± 1.11 μg/kg carfentanil and 17.8 ± 2.03 μg/kg of medetomidine. Deer were reversed by intranasally or intramuscularly administered naltrexone and atipamezole. Dosages of carfentanil and medetomidine proved reliable for immobilization of most, but not all deer, with a mean induction time of 13.3 ± 3.13 min. Effective and reliable immobilization will require higher dosages of carfentanil and possibly medetomidine than were used in this study. No significant differences in recovery times were observed for deer given reversal agents intranasally (9.45 ± 5.37 min) versus intramuscularly (7.60 ± 4.42 min). Naltrexone and atipamezole can be administered intranasally at 1.5 mg/kg and 0.1 mg/kg, respectively to safely and quickly reverse the effects of carfentanil and medetomidine in immobilized white-tailed deer. This route could potentially be useful for other reversal agents. PMID:20676292

  13. Early study on the application of Nexcera ultra low thermal expansion ceramic to space telescopes

    NASA Astrophysics Data System (ADS)

    Kamiya, Tomohiro; Sugawara, Jun; Mizutani, Tadahito; Yasuda, Susumu; Kitamoto, Kazuya

    2017-09-01

    Optical mirrors for space telescopes, which require high precision and high thermal stability, have commonly been made of glass materials such as ultra low expansion glass (e.g. ULE®) or extremely low expansion glassceramic (e.g. ZERODUR® or CLEARCERAM®). These materials have been well-known for their reliability due to their long history of achievements in many space applications.

  14. Monitoring of ULF (ultra-low-frequency) Geomagnetic Variations Associated with Earthquakes

    PubMed Central

    Hayakawa, Masashi; Hattori, Katsumi; Ohta, Kenji

    2007-01-01

    ULF (ultra-low-frequency) electromagnetic emission is recently recognized as one of the most promising candidates for short-term earthquake prediction. This paper reviews previous convincing evidence on the presence of ULF emissions before a few large earthquakes. Then, we present our network of ULF monitoring in the Tokyo area by describing our ULF magnetic sensors and we finally present a few, latest results on seismogenic electromagnetic emissions for recent large earthquakes with the use of sophisticated signal processings.

  15. Low Dose Risk, Decisions, and Risk Communication

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Flynn, James

    The overall research objective was to establish new levels of information about how people, groups, and communities respond to low dose radiation exposure. This is basic research into the social psychology of individual, group, and community responses to radiation exposures. The results of this research are directed to improving risk communication and public participation in management of environmental problems resulting from low dose radiation.

  16. Combating Drug Abuse by Targeting Toll-Like Receptor 4 (TLR4)

    DTIC Science & Technology

    2013-10-01

    dosing with the TLR4 signaling inhibitor (+)- naltrexone ? If so, is Fig  3:  Study  was  conducted  as  previously  described  in...inhibited by systemic dosing with the TLR4 signaling inhibitor (+)- naltrexone ? If so, is morphine reinforcement inhibited by microinjecting LPS-RS into... naltrexone ; drug abuse; glial activation; therapeutic approach to treating drug abuse; opioids; cocaine 16. SECURITY CLASSIFICATION OF: 17

  17. An ultra low-power CMOS automatic action potential detector.

    PubMed

    Gosselin, Benoit; Sawan, Mohamad

    2009-08-01

    We present a low-power complementary metal-oxide semiconductor (CMOS) analog integrated biopotential detector intended for neural recording in wireless multichannel implants. The proposed detector can achieve accurate automatic discrimination of action potential (APs) from the background activity by means of an energy-based preprocessor and a linear delay element. This strategy improves detected waveforms integrity and prompts for better performance in neural prostheses. The delay element is implemented with a low-power continuous-time filter using a ninth-order equiripple allpass transfer function. All circuit building blocks use subthreshold OTAs employing dedicated circuit techniques for achieving ultra low-power and high dynamic range. The proposed circuit function in the submicrowatt range as the implemented CMOS 0.18- microm chip dissipates 780 nW, and it features a size of 0.07 mm(2). So it is suitable for massive integration in a multichannel device with modest overhead. The fabricated detector succeeds to automatically detect APs from underlying background activity. Testbench validation results obtained with synthetic neural waveforms are presented.

  18. Transfer of Low Dose Aspirin Into Human Milk.

    PubMed

    Datta, Palika; Rewers-Felkins, Kathleen; Kallem, Raja Reddy; Baker, Teresa; Hale, Thomas W

    2017-05-01

    Aspirin has antipyretic and anti-inflammatory properties and is frequently used by pregnant and lactating women. However, its transfer in human milk when administered at low dose has not been reported. Research aim: This study aimed to evaluate the transfer of acetylsalicylic acid and its metabolite, salicylic acid, into human milk following the use of low dose aspirin. In this study, milk samples were collected at 0, 1, 2, 4, 8, 12, and 24 hours from seven breastfeeding women after a steady-state daily dose of 81 mg of aspirin. Milk levels of acetylsalicylic acid and salicylic acid were determined by liquid chromatography-tandem mass spectrometry. Acetylsalicylic acid levels were below the limit of quantification (0.61 ng/ml) in all the milk samples, whereas salicylic acid was detected at very low concentrations. The average concentration of salicylic acid observed was 24 ng/ml and the estimated relative infant dose was 0.4%. Acetylsalicylic acid transfer into milk is so low that it is undetectable even by highly sophisticated methodology. Salicylic acid does appear in the human milk in comparatively low amounts, which are probably subclinical in infants. Thus, the daily use of an 81-mg dose of aspirin should be considered safe during lactation.

  19. Restoration of low-dose digital breast tomosynthesis

    NASA Astrophysics Data System (ADS)

    Borges, Lucas R.; Azzari, Lucio; Bakic, Predrag R.; Maidment, Andrew D. A.; Vieira, Marcelo A. C.; Foi, Alessandro

    2018-06-01

    In breast cancer screening, the radiation dose must be kept to the minimum necessary to achieve the desired diagnostic objective, thus minimizing risks associated with cancer induction. However, decreasing the radiation dose also degrades the image quality. In this work we restore digital breast tomosynthesis (DBT) projections acquired at low radiation doses with the goal of achieving a quality comparable to that obtained from current standard full-dose imaging protocols. A multiframe denoising algorithm was applied to low-dose projections, which are filtered jointly. Furthermore, a weighted average was used to inject a varying portion of the noisy signal back into the denoised one, in order to attain a signal-to-noise ratio comparable to that of standard full-dose projections. The entire restoration framework leverages a signal-dependent noise model with quantum gain which varies both upon the projection angle and on the pixel position. A clinical DBT system and a 3D anthropomorphic breast phantom were used to validate the proposed method, both on DBT projections and slices from the 3D reconstructed volume. The framework is shown to attain the standard full-dose image quality from data acquired at 50% lower radiation dose, whereas progressive loss of relevant details compromises the image quality if the dosage is further decreased.

  20. Effects of the Opioid Receptor Antagonist Naltrexone on Smoking and Related Behaviors in Smokers Preparing to Quit: A Randomized Controlled Trial

    PubMed Central

    King, Andrea; Cao, Dingcai; Zhang, Lingjiao; Rueger, Sandra Yu

    2013-01-01

    Aims To determine if naltrexone affects smoking behaviours in smokers preparing to quit, and whether such pre-quit responses predict post-quit date outcomes. Design Double-blind, placebo-controlled, randomized study. Current study focused on smoking-related outcomes in the pre-quit phase, which was one week prior to the quit date, and these findings were linked with reductions in same outcomes demonstrated in the post-quit phase previously published for this RCT in mediation analyses. Setting Community sample of adult smokers desiring to quit in Chicago, Illinois USA. Participants Participants were 315 smokers randomized to naltrexone (n=161; mean age=42.6 years; 60% white) or placebo (n=154; mean age=41.3 years; 55% white). Measurements Difference from baseline in the number of cigarettes smoked during pre-quit phase interval was the primary outcome. Secondary pre-quit outcomes were assessed using Likert scales of subjective responses and consumption of cigarettes, alcohol, and food. Number of cigarettes smoked, alcoholic drinks consumed, and the Brief Questionnaire of Smoking Urges were assessed in the post-quit phase. Findings Relative to placebo, naltrexone decreased the number of cigarettes smoked (−4.21 vs. −2.93, p<.05), smoking urge (p=.02), and number of alcoholic drinks consumed (p=.04). Exploratory mediation analyses linking outcomes of the pre quit and post quit phases found that naltrexone’s effects on reducing smoking urge, cigarettes smoked and alcoholic drinks consumed in the pre-quit phase demonstrated full mediation of their respective effects during the post-quit phase. Conclusions Naltrexone taken in the week before a quit attempt appears to reduce cigarette consumption, urges to smoke and alcohol consumption relative to placebo. The size of the effect statistically mediates the size of similar effects after the quit date. PMID:23714324

  1. Effects of Low-Dose and Very Low-Dose Ketamine among Patients with Major Depression: a Systematic Review and Meta-Analysis.

    PubMed

    Xu, Ying; Hackett, Maree; Carter, Gregory; Loo, Colleen; Gálvez, Verònica; Glozier, Nick; Glue, Paul; Lapidus, Kyle; McGirr, Alexander; Somogyi, Andrew A; Mitchell, Philip B; Rodgers, Anthony

    2016-04-01

    Several recent trials indicate low-dose ketamine produces rapid antidepressant effects. However, uncertainty remains in several areas: dose response, consistency across patient groups, effects on suicidality, and possible biases arising from crossover trials. A systematic search was conducted for relevant randomized trials in Medline, Embase, and PsycINFO databases up to August 2014. The primary endpoints were change in depression scale scores at days 1, 3 and 7, remission, response, suicidality, safety, and tolerability. Data were independently abstracted by 2 reviewers. Where possible, unpublished data were obtained on treatment effects in the first period of crossover trials. Nine trials were identified, including 201 patients (52% female, mean age 46 years). Six trials assessed low-dose ketamine (0.5 mg/kg i.v.) and 3 tested very low-dose ketamine (one trial assessed 50 mg intra-nasal spray, another assessed 0.1-0.4 mg/kg i.v., and another assessed 0.1-0.5 mg/kg i.v., intramuscular, or s.c.). At day 3, the reduction in depression severity score was less marked in the very low-dose trials (P homogeneity <.05) and among bipolar patients. In analyses excluding the second period of crossover trials, response rates at day 7 were increased with ketamine (relative risk 3.4, 95% CI 1.6-7.1, P=.001), as were remission rates (relative risk 2.6, CI 1.2-5.7, P=.02). The absolute benefits were large, with day 7 remission rates of 24% vs 6% (P=.02). Seven trials provided unpublished data on suicidality item scores, which were reduced on days 1 and 3 (both P<.01) but not day 7. Low-dose ketamine appears more effective than very low dose. There is substantial heterogeneity in clinical response, with remission among one-fifth of patients at 1 week but most others having benefits that are less durable. Larger, longer term parallel group trials are needed to determine if efficacy can be extended and to further assess safety. © The Author 2015. Published by Oxford University

  2. Effects of Low-Dose and Very Low-Dose Ketamine among Patients with Major Depression: a Systematic Review and Meta-Analysis

    PubMed Central

    Xu, Ying; Hackett, Maree; Carter, Gregory; Gálvez, Verònica; Glozier, Nick; Glue, Paul; Lapidus, Kyle; McGirr, Alexander; Somogyi, Andrew A.; Mitchell, Philip B.; Rodgers, Anthony

    2016-01-01

    Background: Several recent trials indicate low-dose ketamine produces rapid antidepressant effects. However, uncertainty remains in several areas: dose response, consistency across patient groups, effects on suicidality, and possible biases arising from crossover trials. Methods: A systematic search was conducted for relevant randomized trials in Medline, Embase, and PsycINFO databases up to August 2014. The primary endpoints were change in depression scale scores at days 1, 3 and 7, remission, response, suicidality, safety, and tolerability. Data were independently abstracted by 2 reviewers. Where possible, unpublished data were obtained on treatment effects in the first period of crossover trials. Results: Nine trials were identified, including 201 patients (52% female, mean age 46 years). Six trials assessed low-dose ketamine (0.5mg/kg i.v.) and 3 tested very low-dose ketamine (one trial assessed 50mg intra-nasal spray, another assessed 0.1–0.4mg/kg i.v., and another assessed 0.1–0.5mg/kg i.v., intramuscular, or s.c.). At day 3, the reduction in depression severity score was less marked in the very low-dose trials (P homogeneity <.05) and among bipolar patients. In analyses excluding the second period of crossover trials, response rates at day 7 were increased with ketamine (relative risk 3.4, 95% CI 1.6–7.1, P=.001), as were remission rates (relative risk 2.6, CI 1.2–5.7, P=.02). The absolute benefits were large, with day 7 remission rates of 24% vs 6% (P=.02). Seven trials provided unpublished data on suicidality item scores, which were reduced on days 1 and 3 (both P<.01) but not day 7. Conclusion: Low-dose ketamine appears more effective than very low dose. There is substantial heterogeneity in clinical response, with remission among one-fifth of patients at 1 week but most others having benefits that are less durable. Larger, longer term parallel group trials are needed to determine if efficacy can be extended and to further assess safety. PMID

  3. High-resolution low-dose scanning transmission electron microscopy.

    PubMed

    Buban, James P; Ramasse, Quentin; Gipson, Bryant; Browning, Nigel D; Stahlberg, Henning

    2010-01-01

    During the past two decades instrumentation in scanning transmission electron microscopy (STEM) has pushed toward higher intensity electron probes to increase the signal-to-noise ratio of recorded images. While this is suitable for robust specimens, biological specimens require a much reduced electron dose for high-resolution imaging. We describe here protocols for low-dose STEM image recording with a conventional field-emission gun STEM, while maintaining the high-resolution capability of the instrument. Our findings show that a combination of reduced pixel dwell time and reduced gun current can achieve radiation doses comparable to low-dose TEM.

  4. High- to low-dose extrapolation: critical determinants involved in the dose response of carcinogenic substances.

    PubMed

    Swenberg, J A; Richardson, F C; Boucheron, J A; Deal, F H; Belinsky, S A; Charbonneau, M; Short, B G

    1987-12-01

    Recent investigations on mechanism of carcinogenesis have demonstrated important quantitative relationships between the induction of neoplasia, the molecular dose of promutagenic DNA adducts and their efficiency for causing base-pair mismatch, and the extent of cell proliferation in target organ. These factors are involved in the multistage process of carcinogenesis, including initiation, promotion, and progression. The molecular dose of DNA adducts can exhibit supralinear, linear, or sublinear relationships to external dose due to differences in absorption, biotransformation, and DNA repair at high versus low doses. In contrast, increased cell proliferation is a common phenomena that is associated with exposures to relatively high doses of toxic chemicals. As such, it enhances the carcinogenic response at high doses, but has little effect at low doses. Since data on cell proliferation can be obtained for any exposure scenario and molecular dosimetry studies are beginning to emerge on selected chemical carcinogens, methods are needed so that these critical factors can be utilized in extrapolation from high to low doses and across species. The use of such information may provide a scientific basis for quantitative risk assessment.

  5. What predicts performance in ultra-triathlon races? – a comparison between Ironman distance triathlon and ultra-triathlon

    PubMed Central

    Knechtle, Beat; Zingg, Matthias Alexander; Rosemann, Thomas; Stiefel, Michael; Rüst, Christoph Alexander

    2015-01-01

    Objective This narrative review summarizes recent intentions to find potential predictor variables for ultra-triathlon race performance (ie, triathlon races longer than the Ironman distance covering 3.8 km swimming, 180 km cycling, and 42.195 km running). Results from studies on ultra-triathletes were compared to results on studies on Ironman triathletes. Methods A literature search was performed in PubMed using the terms “ultra”, “triathlon”, and “performance” for the aspects of “ultra-triathlon”, and “Ironman”, “triathlon”, and “performance” for the aspects of “Ironman triathlon”. All resulting papers were searched for related citations. Results for ultra-triathlons were compared to results for Ironman-distance triathlons to find potential differences. Results Athletes competing in Ironman and ultra-triathlon differed in anthropometric and training characteristics, where both Ironmen and ultra-triathletes profited from low body fat, but ultra-triathletes relied more on training volume, whereas speed during training was related to Ironman race time. The most important predictive variables for a fast race time in an ultra-triathlon from Double Iron (ie, 7.6 km swimming, 360 km cycling, and 84.4 km running) and longer were male sex, low body fat, age of 35–40 years, extensive previous experience, a fast time in cycling and running but not in swimming, and origins in Central Europe. Conclusion Any athlete intending to compete in an ultra-triathlon should be aware that low body fat and high training volumes are highly predictive for overall race time. Little is known about the physiological characteristics of these athletes and about female ultra-triathletes. Future studies need to investigate anthropometric and training characteristics of female ultra-triathletes and what motivates women to compete in these races. Future studies need to correlate physiological characteristics such as maximum oxygen uptake (VO2max) with ultra

  6. Induced Mitogenic Activity in AML-12 Mouse Hepatocytes Exposed to Low-dose Ultra-Wideband Electromagnetic Radiation

    PubMed Central

    Dorsey, W. C.; Ford, B. D.; Roane, L.; Haynie, D. T.; Tchounwou, P. B.

    2005-01-01

    Ultra–wideband (UWB) technology has increased with the use of various civilian and military applications. In the present study, we hypothesized that low-dose UWB electromagnetic radiation (UWBR) could elicit a mitogenic effect in AML-12 mouse hepatocytes, in vitro. To test this hypothesis, we exposed AML-12 mouse hepatocytes, to UWBR in a specially constructed gigahertz transverse electromagnetic mode (GTEM) cell. Cells were exposed to UWBR for 2 h at a temperature of 23°C, a pulse width of 10 ns, a repetition rate of 1 kHz, and field strength of 5–20 kV/m. UWB pulses were triggered by an external pulse generator for UWBR exposure but were not triggered for the sham exposure. We performed an MTT Assay to assess cell viability for UWBR-treated and sham-exposed hepatocytes. Data from viability studies indicated a time-related increase in hepatocytes at time intervals from 8–24 h post exposure. UWBR exerted a statistically significant (p < 0.05) dose-dependent response in cell viability in both serum-treated and serum free medium (SFM) -treated hepatocytes. Western blot analysis of hepatocyte lysates demonstrated that cyclin A protein was induced in hepatocytes, suggesting that increased MTT activity after UWBR exposure was due to cell proliferation. This study indicates that UWBR has a mitogenic effect on AML-12 mouse hepatocytes and implicates a possible role for UWBR in hepatocarcinoma. PMID:16705798

  7. PerSEUS: Ultra-Low-Power High Performance Computing for Plasma Simulations

    NASA Astrophysics Data System (ADS)

    Doxas, I.; Andreou, A.; Lyon, J.; Angelopoulos, V.; Lu, S.; Pritchett, P. L.

    2017-12-01

    Peta-op SupErcomputing Unconventional System (PerSEUS) aims to explore the use for High Performance Scientific Computing (HPC) of ultra-low-power mixed signal unconventional computational elements developed by Johns Hopkins University (JHU), and demonstrate that capability on both fluid and particle Plasma codes. We will describe the JHU Mixed-signal Unconventional Supercomputing Elements (MUSE), and report initial results for the Lyon-Fedder-Mobarry (LFM) global magnetospheric MHD code, and a UCLA general purpose relativistic Particle-In-Cell (PIC) code.

  8. Specific gravity and API gravity of biodiesel and ultra-low sulfur diesel (ULSD) blends

    USDA-ARS?s Scientific Manuscript database

    Biodiesel is an alternative fuel made from vegetable oils and animal fats. In 2006, the U. S. Environmental Protection Agency mandated a maximum sulfur content of 15 ppm in on-road diesel fuels. Processing to produce the new ultra-low sulfur petrodiesel (ULSD) alters specific gravity (SG) and othe...

  9. Synergistic effect of low-dose cucurbitacin B and low-dose methotrexate for treatment of human osteosarcoma

    PubMed Central

    Goff, Catherine; Iwanski, Gabriela B.; Forscher, Charles; Doan, Ngan B.; Said, Jonathan W.; Koeffler, H. Phillip

    2016-01-01

    We investigated the use of cucurbitacin B, a plant-derived tetracyclic triterpenoid, as a single agent or in combination with methotrexate (MTX) for human osteosarcoma (OS) treatment. Cucurbitacin B showed antiproliferative activity against seven human OS cell lines in vitro accompanying G2/M cell cycle arrest, apoptosis, and inhibition of ERK, Akt, and mTOR proteins. Cucurbitacin B in combination with MTX synergistically inhibited OS cell growth in vitro. Low-dose cucurbitacin B (LD-CuB, 0.5 mg/kg body weight) or low-dose MTX (LD-MTX, 150 mg/kg) failed to decrease the size of human OS xenografts in nude mice. However, combined therapy at identical concentrations inhibited tumor growth by 62% vs. LD-CuB and 81% vs. LD-MTX (p < 0.001). Strikingly, the effect persisted even when the dose of MTX was decreased by two thirds (VLD-MTX, 50 mg/kg). In conclusion, cucurbitacin B alone or in combination with MTX shows promising antiproliferative activity against human OS. PMID:21440986

  10. A low noise and ultra-narrow bandwidth frequency-locked loop based on the beat method.

    PubMed

    Gao, Wei; Sui, Jianping; Chen, Zhiyong; Yu, Fang; Sheng, Rongwu

    2011-06-01

    A novel frequency-locked loop (FLL) based on the beat method is proposed in this paper. Compared with other frequency feedback loops, this FLL is a digital loop with simple structure and very low noise. As shown in the experimental results, this FLL can be used to reduce close-in phase noise on atomic frequency standards, through which a composite frequency standard with ultra-low phase noise and low cost can be easily realized.

  11. Evaluation of an Ultra-Low Power Reed Solomon Encoder for NASA's Space Technology 5 Mission

    NASA Technical Reports Server (NTRS)

    Li, K. E.; Xapsos, M. A.; Poivey, C.; LaBel, K. A.; Stone, R. F.; Yeh, P-S.; Gambles, J.; Hass, J.; Maki, G.; Marguia, J.

    2003-01-01

    This viewgraph presentation provides information on radiation tests on encoders intended for a constellation of microsatellites. The encoders use CMOS Ultra-Low Power Radiation Tolerant (CULPRiT) technology. The presentation addresses power consumption, radiation dosage, and Single Event Upset (SEU).

  12. Rotatable Small Permanent Magnet Array for Ultra-Low Field Nuclear Magnetic Resonance Instrumentation: A Concept Study

    PubMed Central

    Vegh, Viktor; Reutens, David C.

    2016-01-01

    Object We studied the feasibility of generating the variable magnetic fields required for ultra-low field nuclear magnetic resonance relaxometry with dynamically adjustable permanent magnets. Our motivation was to substitute traditional electromagnets by distributed permanent magnets, increasing system portability. Materials and Methods The finite element method (COMSOL®) was employed for the numerical study of a small permanent magnet array to calculate achievable magnetic field strength, homogeneity, switching time and magnetic forces. A manually operated prototype was simulated and constructed to validate the numerical approach and to verify the generated magnetic field. Results A concentric small permanent magnet array can be used to generate strong sample pre-polarisation and variable measurement fields for ultra-low field relaxometry via simple prescribed magnet rotations. Using the array, it is possible to achieve a pre-polarisation field strength above 100 mT and variable measurement fields ranging from 20–50 μT with 200 ppm absolute field homogeneity within a field-of-view of 5 x 5 x 5 cubic centimetres. Conclusions A dynamic small permanent magnet array can generate multiple highly homogeneous magnetic fields required in ultra-low field nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) instruments. This design can significantly reduce the volume and energy requirements of traditional systems based on electromagnets, improving portability considerably. PMID:27271886

  13. Metabonomics evaluation of urine from rats administered with phorate under long-term and low-level exposure by ultra-performance liquid chromatography-mass spectrometry.

    PubMed

    Sun, Xiaowei; Xu, Wei; Zeng, Yan; Hou, Yurong; Guo, Lin; Zhao, Xiujuan; Sun, Changhao

    2014-02-01

    The purpose of this study was to investigate the toxic effect of long-term and low-level exposure to phorate using a metabonomics approach based on ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). Male Wistar rats were given phorate daily in drinking water at low doses of 0.05, 0.15 or 0.45 mg kg⁻¹ body weight (BW) for 24 weeks consecutively. Rats in the control group were given an equivalent volume of drinking water. Compared with the control group, serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin (TBIL), urea nitrogen (BUN) and creatinine (CR) were increased in the middle- and high-dose groups whereas albumin (ALB) and cholinesterase (CHE) were decreased. Urine metabonomics profiles were analyzed by UPLC-MS. Compared with the control group, 12 metabolites were significantly changed in phorate-treated groups. In the negative mode, metabolite intensities of uric acid, suberic acid and citric acid were significantly decreased in the middle- and high-dose groups, whereas indoxyl sulfic acid (indican) and cholic acid were increased. In the positive mode, uric acid, creatinine, kynurenic acid and xanthurenic acid were significantly decreased in the middle- and high-dose groups, but 7-methylguanine (N⁷G) was increased. In both negative and positive modes, diethylthiophosphate (DETP) was significantly increased, which was considered as a biomarker of exposure to phorate. In conclusion, long-term and low-level exposure to phorate can cause disturbances in energy-related metabolism, liver and kidney function, the antioxidant system, and DNA damage. Moreover, more information can be provided on the evaluation of toxicity of phorate using metabonomics combined with clinical chemistry. Copyright © 2012 John Wiley & Sons, Ltd.

  14. Fabrication of ultra thin anodic aluminium oxide membranes by low anodization voltages

    NASA Astrophysics Data System (ADS)

    Pastore, I.; Poplausks, R.; Apsite, I.; Pastare, I.; Lombardi, F.; Erts, D.

    2011-06-01

    Formation of ultrathin anodised aluminium oxide (AAO) membranes with high aspect ratio by Al anodization in sulphuric and oxalic acids at low potentials was investigated. Low anodization potentials ensure slow electrochemical reaction speeds and formation of AAO membranes with pore diameter and thickness below 20 nm and 70 nm respectively. Minimum time necessary for formation of continuous AAO membranes was determined. AAO membrane pore surface was covered with polymer Paraloid B72TM to transport it to the selected substrate. The fabricated ultra thin AAO membranes could be used to fabricate nanodot arrays on different surfaces.

  15. Ultra-low power operation of self-heated, suspended carbon nanotube gas sensors

    NASA Astrophysics Data System (ADS)

    Chikkadi, Kiran; Muoth, Matthias; Maiwald, Verena; Roman, Cosmin; Hierold, Christofer

    2013-11-01

    We present a suspended carbon nanotube gas sensor that senses NO2 at ambient temperature and recovers from gas exposure at an extremely low power of 2.9 μW by exploiting the self-heating effect for accelerated gas desorption. The recovery time of 10 min is two orders of magnitude faster than non-heated recovery at ambient temperature. This overcomes an important bottleneck for the practical application of carbon nanotube gas sensors. Furthermore, the method is easy to implement in sensor systems and requires no additional components, paving the way for ultra-low power, compact, and highly sensitive gas sensors.

  16. Dedicated power supply subsystem for ultra-low noise preamplifiers and biophotonic sensors

    NASA Astrophysics Data System (ADS)

    SuraŻyński, Łukasz; Wierzba, Paweł; Zienkiewicz, Aleksandra

    2013-11-01

    It is very common for noise to have an influence on analog circuits. In order to preserve the quality of measurements taken by specific sensors and any noise dependent amplifiers which are correlated to them, all of these devices must be powered by low-noise power supplies. Therefore a necessity exists to develop new ultra-low noise power supplies which can cooperate with specified amplifiers and preamplifiers. Many well-known power supplies are particularly expensive and yet still have their disadvantages. This paper proposes a simple and inexpensive solution, which fulfills a specific criteria and can be treated as a base for improvement.

  17. How Many Ultra-Low Delta-v Near Earth Objects Remain Undiscovered? Implications for missions.

    NASA Astrophysics Data System (ADS)

    Elvis, Martin; Ranjan, Sukrit; Galache, Jose Luis; Murphy, Max

    2015-08-01

    The past decade has witnessed considerable growth of interest in missions to Near-Earth Objects (NEOs). NEOs are considered prime targets for manned and robotic missions, for both scientific objectives as well as in-situ resource utilization including harvesting of water for propellant and life support and mining of high-value elements for sale on Earth. Appropriate targets are crucial to such missions. Hence, ultra-low delta-v mission targets are strongly favored. Some mission architectures rely on the discovery of more ultra-low delta-v NEOs. In fact the approved and executed NEO missions have all targeted asteroids with ultra-low LEO to asteroid rendezvous delta-v <5.5 km/s.In this paper, we estimate the total NEO population as a function of delta-v, and how many remain to be discovered in various size ranges down to ~100m. We couple the NEOSSat-1 model (Greenstreet et al., 2012) to the NEO size distribution derived from the NEOWISE survey (Mainzer et al., 2011b) to compute an absolute NEO population model. We compare the Minor Planet Center (MPC) catalog of known NEOs to this NEO population model. We compute the delta-v from LEO to asteroid rendezvous orbits using a modified Shoemaker-Helin (S-H) formalism that empirically removes biases found comparing S-H with the results from NHATS. The median delta-v of the known NEOs is 7.3 km/s, the median delta-v predicted by our NEO model is 9.8 km/s, suggesting that undiscovered objects are biased to higher delta-v. The survey of delta-v <10.3 km/s NEOs is essentially complete for objects with diameter D >300 m. However, there are tens of thousands of objects with delta-v <10.3 km/s to be discovered in the D = 50 - 300 m size class (H = 20.4 - 24.3). Our work suggests that there are 100 yet-undiscovered NEOs with delta-v < 5:8 km/s, and 1000 undiscovered NEOs with v < 6.3 km/s. We conclude that, even with complete NEO surveys, the selection of good (i.e. ultra-low delta-v) mission targets is limited given current

  18. Reduced lung-cancer mortality with low-dose computed tomographic screening.

    PubMed

    Aberle, Denise R; Adams, Amanda M; Berg, Christine D; Black, William C; Clapp, Jonathan D; Fagerstrom, Richard M; Gareen, Ilana F; Gatsonis, Constantine; Marcus, Pamela M; Sicks, JoRean D

    2011-08-04

    The aggressive and heterogeneous nature of lung cancer has thwarted efforts to reduce mortality from this cancer through the use of screening. The advent of low-dose helical computed tomography (CT) altered the landscape of lung-cancer screening, with studies indicating that low-dose CT detects many tumors at early stages. The National Lung Screening Trial (NLST) was conducted to determine whether screening with low-dose CT could reduce mortality from lung cancer. From August 2002 through April 2004, we enrolled 53,454 persons at high risk for lung cancer at 33 U.S. medical centers. Participants were randomly assigned to undergo three annual screenings with either low-dose CT (26,722 participants) or single-view posteroanterior chest radiography (26,732). Data were collected on cases of lung cancer and deaths from lung cancer that occurred through December 31, 2009. The rate of adherence to screening was more than 90%. The rate of positive screening tests was 24.2% with low-dose CT and 6.9% with radiography over all three rounds. A total of 96.4% of the positive screening results in the low-dose CT group and 94.5% in the radiography group were false positive results. The incidence of lung cancer was 645 cases per 100,000 person-years (1060 cancers) in the low-dose CT group, as compared with 572 cases per 100,000 person-years (941 cancers) in the radiography group (rate ratio, 1.13; 95% confidence interval [CI], 1.03 to 1.23). There were 247 deaths from lung cancer per 100,000 person-years in the low-dose CT group and 309 deaths per 100,000 person-years in the radiography group, representing a relative reduction in mortality from lung cancer with low-dose CT screening of 20.0% (95% CI, 6.8 to 26.7; P=0.004). The rate of death from any cause was reduced in the low-dose CT group, as compared with the radiography group, by 6.7% (95% CI, 1.2 to 13.6; P=0.02). Screening with the use of low-dose CT reduces mortality from lung cancer. (Funded by the National Cancer

  19. The effect of ultra-violet light curing on the molecular structure and fracture properties of an ultra low-k material

    NASA Astrophysics Data System (ADS)

    Smith, Ryan Scott

    As the gate density increases in microelectronic devices, the interconnect delay or RC response also increases and has become the limiting delay to faster devices. In order to decrease the RC time delay, a new metallization scheme has been chosen by the semiconductor industry. Copper has replaced aluminum as the metal lines and new low-k dielectric materials are being developed to replace silicon dioxide. A promising low-k material is porous organosilicate glass or p-OSG. The p-OSG film is a hybrid material where the silicon dioxide backbone is terminated with methyl or hydrogen, reducing the dielectric constant and creating mechanically weak films that are prone to fracture. A few methods of improving the mechanical properties of p-OSG films have been attempted-- exposing the film to hydrogen plasma, electron beam curing, and ultra-violet light curing. Hydrogen plasma and electron-beam curing suffer from a lack of specificity and can cause charging damage to the gates. Therefore, ultra-violet light curing (UV curing) is preferable. The effect of UV curing on an ultra-low-k, k~2.5, p-OSG film is studied in this dissertation. Changes in the molecular structure were measured with Fourier Transform Infrared Spectroscopy and X-ray Photoelectron Spectroscopy. The evolution of the molecular structure with UV curing was correlated with material and fracture properties. The material properties were film shrinkage, densification, and an increase in dielectric constant. From the changes in molecular structure and material properties, a set of condensation reactions with UV light are predicted. The connectivity of the film increases with the condensation reactions and, therefore, the fracture toughness should also increase. The effect of UV curing on the critical and sub-critical fracture toughness was also studied. The critical fracture toughness was measured at four different mode-mixes-- zero, 15°, 32°, and 42°. It was found that the critical fracture toughness

  20. a-SiNx:H-based ultra-low power resistive random access memory with tunable Si dangling bond conduction paths.

    PubMed

    Jiang, Xiaofan; Ma, Zhongyuan; Xu, Jun; Chen, Kunji; Xu, Ling; Li, Wei; Huang, Xinfan; Feng, Duan

    2015-10-28

    The realization of ultra-low power Si-based resistive switching memory technology will be a milestone in the development of next generation non-volatile memory. Here we show that a high performance and ultra-low power resistive random access memory (RRAM) based on an Al/a-SiNx:H/p(+)-Si structure can be achieved by tuning the Si dangling bond conduction paths. We reveal the intrinsic relationship between the Si dangling bonds and the N/Si ratio x for the a-SiNx:H films, which ensures that the programming current can be reduced to less than 1 μA by increasing the value of x. Theoretically calculated current-voltage (I-V) curves combined with the temperature dependence of the I-V characteristics confirm that, for the low-resistance state (LRS), the Si dangling bond conduction paths obey the trap-assisted tunneling model. In the high-resistance state (HRS), conduction is dominated by either hopping or Poole-Frenkel (P-F) processes. Our introduction of hydrogen in the a-SiNx:H layer provides a new way to control the Si dangling bond conduction paths, and thus opens up a research field for ultra-low power Si-based RRAM.

  1. Generative Adversarial Networks for Noise Reduction in Low-Dose CT.

    PubMed

    Wolterink, Jelmer M; Leiner, Tim; Viergever, Max A; Isgum, Ivana

    2017-12-01

    Noise is inherent to low-dose CT acquisition. We propose to train a convolutional neural network (CNN) jointly with an adversarial CNN to estimate routine-dose CT images from low-dose CT images and hence reduce noise. A generator CNN was trained to transform low-dose CT images into routine-dose CT images using voxelwise loss minimization. An adversarial discriminator CNN was simultaneously trained to distinguish the output of the generator from routine-dose CT images. The performance of this discriminator was used as an adversarial loss for the generator. Experiments were performed using CT images of an anthropomorphic phantom containing calcium inserts, as well as patient non-contrast-enhanced cardiac CT images. The phantom and patients were scanned at 20% and 100% routine clinical dose. Three training strategies were compared: the first used only voxelwise loss, the second combined voxelwise loss and adversarial loss, and the third used only adversarial loss. The results showed that training with only voxelwise loss resulted in the highest peak signal-to-noise ratio with respect to reference routine-dose images. However, CNNs trained with adversarial loss captured image statistics of routine-dose images better. Noise reduction improved quantification of low-density calcified inserts in phantom CT images and allowed coronary calcium scoring in low-dose patient CT images with high noise levels. Testing took less than 10 s per CT volume. CNN-based low-dose CT noise reduction in the image domain is feasible. Training with an adversarial network improves the CNNs ability to generate images with an appearance similar to that of reference routine-dose CT images.

  2. Remote Sensing Extraction of Stopes and Tailings Ponds in AN Ultra-Low Iron Mining Area

    NASA Astrophysics Data System (ADS)

    Ma, B.; Chen, Y.; Li, X.; Wu, L.

    2018-04-01

    With the development of economy, global demand for steel has accelerated since 2000, and thus mining activities of iron ore have become intensive accordingly. An ultra-low-grade iron has been extracted by open-pit mining and processed massively since 2001 in Kuancheng County, Hebei Province. There are large-scale stopes and tailings ponds in this area. It is important to extract their spatial distribution information for environmental protection and disaster prevention. A remote sensing method of extracting stopes and tailings ponds is studied based on spectral characteristics by use of Landsat 8 OLI imagery and ground spectral data. The overall accuracy of extraction is 95.06 %. In addition, tailings ponds are distinguished from stopes based on thermal characteristics by use of temperature image. The results could provide decision support for environmental protection, disaster prevention, and ecological restoration in the ultra-low-grade iron ore mining area.

  3. Acute antidepressant effects of right unilateral ultra-brief ECT: a double-blind randomised controlled trial.

    PubMed

    Mayur, Prashanth; Byth, Karen; Harris, Anthony

    2013-07-01

    Shortening the pulse width to 0.3 ms holds neurophysiological and clinical promise of making ECT safer by limiting cognitive side effects. However, the antidepressant effects of right ultra-brief unilateral ECT are under contention. In an acute ECT course, antidepressant equivalence of ultra-brief right unilateral ECT to the high-dose brief pulse right unilateral ECT was investigated. Severely depressed patients were randomised to 1 ms-brief pulse (n=18) or 0.3 ms ultra-brief pulse (n=17) right unilateral ECT, both at high-dose (6 times threshold stimulus dose) given thrice weekly. Depression severity was measured using the Montgomery Asberg Depression Rating Scale at baseline, after 8 treatments and after the acute course of ECT. Depression severity declined equally in both groups: F (1.27,41.97)=0.31, p=0.63. Median time in days to remission (95%CI) was in brief pulse ECT: 26 (18.6-33.4) and ultra-brief pulse ECT:28 (17.9-38.0). The small sample study in the study increases the likelihood of type 2 error. In severe depression, high-dose ultra-brief right unilateral ECT appears to show matching acute antidepressant response to an equally high-dose brief pulse right unilateral ECT. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Low-dose adenosine stress echocardiography: detection of myocardial viability.

    PubMed

    Djordjevic-Dikic, Ana; Ostojic, Miodrag; Beleslin, Branko; Nedeljkovic, Ivana; Stepanovic, Jelena; Stojkovic, Sinisa; Petrasinovic, Zorica; Nedeljkovic, Milan; Saponjski, Jovica; Giga, Vojislav

    2003-06-03

    The aim of this study was to evaluate the diagnostic potential of low-dose adenosine stress echocardiography in detection of myocardial viability. Vasodilation through low dose dipyridamole infusion may recruit contractile reserve by increasing coronary flow or by increasing levels of endogenous adenosine. Forty-three patients with resting dyssynergy, due to previous myocardial infarction, underwent low-dose adenosine (80, 100, 110 mcg/kg/min in 3 minutes intervals) echocardiography test. Gold standard for myocardial viability was improvement in systolic thickening of dyssinergic segments of >or= 1 grade at follow-up. Coronary angiography was done in 41 pts. Twenty-seven patients were revascularized and 16 were medically treated. Echocardiographic follow up data (12 +/- 2 months) were available in 24 revascularized patients. Wall motion score index improved from rest 1.55 +/- 0.30 to 1.33 +/- 0.26 at low-dose adenosine (p < 0.001). Of the 257 segments with baseline dyssynergy, adenosine echocardiography identified 122 segments as positive for viability, and 135 as necrotic since no improvement of systolic thickening was observed. Follow-up wall motion score index was 1.31 +/- 0.30 (p < 0.001 vs. rest). The sensitivity of adenosine echo test for identification of viable segments was 87%, while specificity was 95%, and diagnostic accuracy 90%. Positive and negative predictive values were 97% and 80%, respectively. Low-dose adenosine stress echocardiography test has high diagnostic potential for detection of myocardial viability in the group of patients with left ventricle dysfunction due to previous myocardial infarction. Low dose adenosine stress echocardiography may be adequate alternative to low-dose dobutamine test for evaluation of myocardial viability.

  5. Low-dose adenosine stress echocardiography: Detection of myocardial viability

    PubMed Central

    Djordjevic-Dikic, Ana; Ostojic, Miodrag; Beleslin, Branko; Nedeljkovic, Ivana; Stepanovic, Jelena; Stojkovic, Sinisa; Petrasinovic, Zorica; Nedeljkovic, Milan; Saponjski, Jovica; Giga, Vojislav

    2003-01-01

    Objective The aim of this study was to evaluate the diagnostic potential of low-dose adenosine stress echocardiography in detection of myocardial viability. Background Vasodilation through low dose dipyridamole infusion may recruit contractile reserve by increasing coronary flow or by increasing levels of endogenous adenosine. Methods Forty-three patients with resting dyssynergy, due to previous myocardial infarction, underwent low-dose adenosine (80, 100, 110 mcg/kg/min in 3 minutes intervals) echocardiography test. Gold standard for myocardial viability was improvement in systolic thickening of dyssinergic segments of ≥ 1 grade at follow-up. Coronary angiography was done in 41 pts. Twenty-seven patients were revascularized and 16 were medically treated. Echocardiographic follow up data (12 ± 2 months) were available in 24 revascularized patients. Results Wall motion score index improved from rest 1.55 ± 0.30 to 1.33 ± 0.26 at low-dose adenosine (p < 0.001). Of the 257 segments with baseline dyssynergy, adenosine echocardiography identified 122 segments as positive for viability, and 135 as necrotic since no improvement of systolic thickening was observed. Follow-up wall motion score index was 1.31 ± 0.30 (p < 0.001 vs. rest). The sensitivity of adenosine echo test for identification of viable segments was 87%, while specificity was 95%, and diagnostic accuracy 90%. Positive and negative predictive values were 97% and 80%, respectively. Conclusion Low-dose adenosine stress echocardiography test has high diagnostic potential for detection of myocardial viability in the group of patients with left ventricle dysfunction due to previous myocardial infarction. Low dose adenosine stress echocardiography may be adequate alternative to low-dose dobutamine test for evaluation of myocardial viability. PMID:12812523

  6. Single-mode optical fiber design with wide-band ultra low bending-loss for FTTH application.

    PubMed

    Watekar, Pramod R; Ju, Seongmin; Han, Won-Taek

    2008-01-21

    We propose a new design of a single-mode optical fiber (SMF) which exhibits ultra low bend sensitivity over a wide communication band (1.3 microm to 1.65 microm). A five-cladding fiber structure has been proposed to minimize the bending loss, estimated to be as low as 4.4x10(-10) dB/turn for the bend radius of 10 mm.

  7. High- to low-dose extrapolation: critical determinants involved in the dose response of carcinogenic substances.

    PubMed Central

    Swenberg, J A; Richardson, F C; Boucheron, J A; Deal, F H; Belinsky, S A; Charbonneau, M; Short, B G

    1987-01-01

    Recent investigations on mechanism of carcinogenesis have demonstrated important quantitative relationships between the induction of neoplasia, the molecular dose of promutagenic DNA adducts and their efficiency for causing base-pair mismatch, and the extent of cell proliferation in target organ. These factors are involved in the multistage process of carcinogenesis, including initiation, promotion, and progression. The molecular dose of DNA adducts can exhibit supralinear, linear, or sublinear relationships to external dose due to differences in absorption, biotransformation, and DNA repair at high versus low doses. In contrast, increased cell proliferation is a common phenomena that is associated with exposures to relatively high doses of toxic chemicals. As such, it enhances the carcinogenic response at high doses, but has little effect at low doses. Since data on cell proliferation can be obtained for any exposure scenario and molecular dosimetry studies are beginning to emerge on selected chemical carcinogens, methods are needed so that these critical factors can be utilized in extrapolation from high to low doses and across species. The use of such information may provide a scientific basis for quantitative risk assessment. PMID:3447904

  8. Fully Convolutional Architecture for Low-Dose CT Image Noise Reduction

    NASA Astrophysics Data System (ADS)

    Badretale, S.; Shaker, F.; Babyn, P.; Alirezaie, J.

    2017-10-01

    One of the critical topics in medical low-dose Computed Tomography (CT) imaging is how best to maintain image quality. As the quality of images decreases with lowering the X-ray radiation dose, improving image quality is extremely important and challenging. We have proposed a novel approach to denoise low-dose CT images. Our algorithm learns directly from an end-to-end mapping from the low-dose Computed Tomography images for denoising the normal-dose CT images. Our method is based on a deep convolutional neural network with rectified linear units. By learning various low-level to high-level features from a low-dose image the proposed algorithm is capable of creating a high-quality denoised image. We demonstrate the superiority of our technique by comparing the results with two other state-of-the-art methods in terms of the peak signal to noise ratio, root mean square error, and a structural similarity index.

  9. Low-dose dopamine or low-dose nesiritide in acute heart failure with renal dysfunction: the ROSE acute heart failure randomized trial.

    PubMed

    Chen, Horng H; Anstrom, Kevin J; Givertz, Michael M; Stevenson, Lynne W; Semigran, Marc J; Goldsmith, Steven R; Bart, Bradley A; Bull, David A; Stehlik, Josef; LeWinter, Martin M; Konstam, Marvin A; Huggins, Gordon S; Rouleau, Jean L; O'Meara, Eileen; Tang, W H Wilson; Starling, Randall C; Butler, Javed; Deswal, Anita; Felker, G Michael; O'Connor, Christopher M; Bonita, Raphael E; Margulies, Kenneth B; Cappola, Thomas P; Ofili, Elizabeth O; Mann, Douglas L; Dávila-Román, Víctor G; McNulty, Steven E; Borlaug, Barry A; Velazquez, Eric J; Lee, Kerry L; Shah, Monica R; Hernandez, Adrian F; Braunwald, Eugene; Redfield, Margaret M

    2013-12-18

    Small studies suggest that low-dose dopamine or low-dose nesiritide may enhance decongestion and preserve renal function in patients with acute heart failure and renal dysfunction; however, neither strategy has been rigorously tested. To test the 2 independent hypotheses that, compared with placebo, addition of low-dose dopamine (2 μg/kg/min) or low-dose nesiritide (0.005 μg/kg/min without bolus) to diuretic therapy will enhance decongestion and preserve renal function in patients with acute heart failure and renal dysfunction. Multicenter, double-blind, placebo-controlled clinical trial (Renal Optimization Strategies Evaluation [ROSE]) of 360 hospitalized patients with acute heart failure and renal dysfunction (estimated glomerular filtration rate of 15-60 mL/min/1.73 m2), randomized within 24 hours of admission. Enrollment occurred from September 2010 to March 2013 across 26 sites in North America. Participants were randomized in an open, 1:1 allocation ratio to the dopamine or nesiritide strategy. Within each strategy, participants were randomized in a double-blind, 2:1 ratio to active treatment or placebo. The dopamine (n = 122) and nesiritide (n = 119) groups were independently compared with the pooled placebo group (n = 119). Coprimary end points included 72-hour cumulative urine volume (decongestion end point) and the change in serum cystatin C from enrollment to 72 hours (renal function end point). Compared with placebo, low-dose dopamine had no significant effect on 72-hour cumulative urine volume (dopamine, 8524 mL; 95% CI, 7917-9131 vs placebo, 8296 mL; 95% CI, 7762-8830 ; difference, 229 mL; 95% CI, -714 to 1171 mL; P = .59) or on the change in cystatin C level (dopamine, 0.12 mg/L; 95% CI, 0.06-0.18 vs placebo, 0.11 mg/L; 95% CI, 0.06-0.16; difference, 0.01; 95% CI, -0.08 to 0.10; P = .72). Similarly, low-dose nesiritide had no significant effect on 72-hour cumulative urine volume (nesiritide, 8574 mL; 95% CI, 8014-9134 vs placebo

  10. Ultra-low density microcellular polymer foam and method

    DOEpatents

    Simandl, Ronald F.; Brown, John D.

    1996-01-01

    An ultra-low density, microcellular open-celled polymer foam and a method for making such foam. A polymer is dissolved in a heated solution consisting essentially of at least one solvent for the dissolution of the polymer in the heated solution and the phase inversion of the dissolved polymer to a liquid gel upon sufficient cooling of the heated solution. The heated solution is contained in a containment means provided with a nucleating promoting means having a relatively rough surface formed of fixed nucleating sites. The heated solution is cooled for a period of time sufficient to form a liquid gel of the polymer by phase inversion. From the gel, a porous foam having a density of less than about 12.0 mg/cm.sup.3 and open porosity provided by well interconnected strut morphology is formed.

  11. Ultra-low density microcellular polymer foam and method

    DOEpatents

    Simandl, R.F.; Brown, J.D.

    1996-03-19

    An ultra-low density, microcellular open-celled polymer foam and a method for making such foam are disclosed. A polymer is dissolved in a heated solution consisting essentially of at least one solvent for the dissolution of the polymer in the heated solution and the phase inversion of the dissolved polymer to a liquid gel upon sufficient cooling of the heated solution. The heated solution is contained in a containment means provided with a nucleating promoting means having a relatively rough surface formed of fixed nucleating sites. The heated solution is cooled for a period of time sufficient to form a liquid gel of the polymer by phase inversion. From the gel, a porous foam having a density of less than about 12.0 mg/cm{sup 3} and open porosity provided by well interconnected strut morphology is formed.

  12. Ultra-low power high temperature and radiation hard complementary metal-oxide-semiconductor (CMOS) silicon-on-insulator (SOI) voltage reference.

    PubMed

    Boufouss, El Hafed; Francis, Laurent A; Kilchytska, Valeriya; Gérard, Pierre; Simon, Pascal; Flandre, Denis

    2013-12-13

    This paper presents an ultra-low power CMOS voltage reference circuit which is robust under biomedical extreme conditions, such as high temperature and high total ionized dose (TID) radiation. To achieve such performances, the voltage reference is designed in a suitable 130 nm Silicon-on-Insulator (SOI) industrial technology and is optimized to work in the subthreshold regime of the transistors. The design simulations have been performed over the temperature range of -40-200 °C and for different process corners. Robustness to radiation was simulated using custom model parameters including TID effects, such as mobilities and threshold voltages degradation. The proposed circuit has been tested up to high total radiation dose, i.e., 1 Mrad (Si) performed at three different temperatures (room temperature, 100 °C and 200 °C). The maximum drift of the reference voltage V(REF) depends on the considered temperature and on radiation dose; however, it remains lower than 10% of the mean value of 1.5 V. The typical power dissipation at 2.5 V supply voltage is about 20 μW at room temperature and only 75 μW at a high temperature of 200 °C. To understand the effects caused by the combination of high total ionizing dose and temperature on such voltage reference, the threshold voltages of the used SOI MOSFETs were extracted under different conditions. The evolution of V(REF) and power consumption with temperature and radiation dose can then be explained in terms of the different balance between fixed oxide charge and interface states build-up. The total occupied area including pad-ring is less than 0.09 mm2.

  13. Ultra-low-noise transition edge sensors for the SAFARI L-band on SPICA

    NASA Astrophysics Data System (ADS)

    Goldie, D. J.; Gao, J. R.; Glowacka, D. M.; Griffin, D. K.; Hijmering, R.; Khosropanah, P.; Jackson, B. D.; Mauskopf, P. D.; Morozov, D.; Murphy, J. A.; Ridder, M.; Trappe, N.; O'Sullivan, C.; Withington, S.

    2012-09-01

    The Far-Infrared Fourier transform spectrometer instrument SAFARI-SPICA which will operate with cooled optics in a low-background space environment requires ultra-sensitive detector arrays with high optical coupling efficiencies over extremely wide bandwidths. In earlier papers we described the design, fabrication and performance of ultra-low-noise Transition Edge Sensors (TESs) operated close to 100mk having dark Noise Equivalent Powers (NEPs) of order 4 × 10-19W/√Hz close to the phonon noise limit and an improvement of two orders of magnitude over TESs for ground-based applications. Here we describe the design, fabrication and testing of 388-element arrays of MoAu TESs integrated with far-infrared absorbers and optical coupling structures in a geometry appropriate for the SAFARI L-band (110 - 210 μm). The measured performance shows intrinsic response time τ ~ 11ms and saturation powers of order 10 fW, and a dark noise equivalent powers of order 7 × 10-19W/√Hz. The 100 × 100μm2 MoAu TESs have transition temperatures of order 110mK and are coupled to 320×320μm2 thin-film β-phase Ta absorbers to provide impedance matching to the incoming fields. We describe results of dark tests (i.e without optical power) to determine intrinsic pixel characteristics and their uniformity, and measurements of the optical performance of representative pixels operated with flat back-shorts coupled to pyramidal horn arrays. The measured and modeled optical efficiency is dominated by the 95Ω sheet resistance of the Ta absorbers, indicating a clear route to achieve the required performance in these ultra-sensitive detectors.

  14. An ultra-low-power RF transceiver for WBANs in medical applications

    NASA Astrophysics Data System (ADS)

    Qi, Zhang; Xiaofei, Kuang; Nanjian, Wu

    2011-06-01

    A 2.4 GHz ultra-low-power RF transceiver with a 900 MHz auxiliary wake-up link for wireless body area networks (WBANs) in medical applications is presented. The RF transceiver with an asymmetric architecture is proposed to achieve high energy efficiency according to the asymmetric communication in WBANs. The transceiver consists of a main receiver (RX) with an ultra-low-power free-running ring oscillator and a high speed main transmitter (TX) with fast lock-in PLL. A passive wake-up receiver (WuRx) for wake-up function with a high power conversion efficiency (PCE) CMOS rectifier is designed to offer the sensor node the capability of work-on-demand with zero standby power. The chip is implemented in a 0.18 μm CMOS process. Its core area is 1.6 mm2. The main RX achieves a sensitivity of -55 dBm at a 100 kbps OOK data rate while consuming just 210 μA current from the 1 V power supply. The main TX achieves +3 dBm output power with a 4 Mbps/500 kbps/200 kbps data rate for OOK/4 FSK/2 FSK modulation and dissipates 3.25 mA/6.5 mA/6.5 mA current from a 1.8 V power supply. The minimum detectable RF input energy for the wake-up RX is -15 dBm and the PCE is more than 25%.

  15. Ultra Low Density and Highly Crosslinked Biocompatible Shape Memory Polyurethane Foams

    PubMed Central

    Singhal, Pooja; Rodriguez, Jennifer N.; Small, Ward; Eagleston, Scott; Van de Water, Judy; Maitland, Duncan J.; Wilson, Thomas S.

    2012-01-01

    We report the development of highly chemically crosslinked, ultra low density (~0.015 g/cc) polyurethane shape memory foams synthesized from symmetrical, low molecular weight and branched hydroxyl monomers. Sharp single glass transitions (Tg) customizable in the functional range of 45–70 °C were achieved. Thermomechanical testing confirmed shape memory behavior with 97–98% shape recovery over repeated cycles, a glassy storage modulus of 200–300 kPa and recovery stresses of 5–15 kPa. Shape holding tests under constrained storage above the Tg showed stable shape memory. A high volume expansion of up to 70 times was seen on actuation of these foams from a fully compressed state. Low in-vitro cell activation induced by the foam compared to controls demonstrates low acute bio-reactivity. We believe these porous polymeric scaffolds constitute an important class of novel smart biomaterials with multiple potential applications. PMID:22570509

  16. Automated coronary artery calcification detection on low-dose chest CT images

    NASA Astrophysics Data System (ADS)

    Xie, Yiting; Cham, Matthew D.; Henschke, Claudia; Yankelevitz, David; Reeves, Anthony P.

    2014-03-01

    Coronary artery calcification (CAC) measurement from low-dose CT images can be used to assess the risk of coronary artery disease. A fully automatic algorithm to detect and measure CAC from low-dose non-contrast, non-ECG-gated chest CT scans is presented. Based on the automatically detected CAC, the Agatston score (AS), mass score and volume score were computed. These were compared with scores obtained manually from standard-dose ECG-gated scans and low-dose un-gated scans of the same patient. The automatic algorithm segments the heart region based on other pre-segmented organs to provide a coronary region mask. The mitral valve and aortic valve calcification is identified and excluded. All remaining voxels greater than 180HU within the mask region are considered as CAC candidates. The heart segmentation algorithm was evaluated on 400 non-contrast cases with both low-dose and regular dose CT scans. By visual inspection, 371 (92.8%) of the segmentations were acceptable. The automated CAC detection algorithm was evaluated on 41 low-dose non-contrast CT scans. Manual markings were performed on both low-dose and standard-dose scans for these cases. Using linear regression, the correlation of the automatic AS with the standard-dose manual scores was 0.86; with the low-dose manual scores the correlation was 0.91. Standard risk categories were also computed. The automated method risk category agreed with manual markings of gated scans for 24 cases while 15 cases were 1 category off. For low-dose scans, the automatic method agreed with 33 cases while 7 cases were 1 category off.

  17. Different dose rate-dependent responses of human melanoma cells and fibroblasts to low dose fast neutrons.

    PubMed

    Dionet, Claude; Müller-Barthélémy, Melanie; Marceau, Geoffroy; Denis, Jean-Marc; Averbeck, Dietrich; Gueulette, John; Sapin, Vincent; Pereira, Bruno; Tchirkov, Andrei; Chautard, Emmanuel; Verrelle, Pierre

    2016-09-01

    To analyze the dose rate influence in hyper-radiosensitivity (HRS) of human melanoma cells to very low doses of fast neutrons and to compare to the behaviour of normal human skin fibroblasts. We explored different neutron dose rates as well as possible implication of DNA double-strand breaks (DSB), apoptosis, and energy-provider adenosine-triphosphate (ATP) levels during HRS. HRS in melanoma cells appears only at a very low dose rate (VLDR), while a high dose rate (HDR) induces an initial cell-radioresistance (ICRR). HRS does not seem to be due either to DSB or to apoptosis. Both phenomena (HRS and ICRR) appear to be related to ATP availability for triggering cell repair. Fibroblast survival after neutron irradiation is also dose rate-dependent but without HRS. Melanoma cells or fibroblasts exert their own survival behaviour at very low doses of neutrons, suggesting that in some cases there is a differential between cancer and normal cells radiation responses. Only the survival of fibroblasts at HDR fits the linear no-threshold model. This new insight into human cell responses to very low doses of neutrons, concerns natural radiations, surroundings of accelerators, proton-therapy devices, flights at high altitude. Furthermore, ATP inhibitors could increase HRS during high-linear energy transfer (high-LET) irradiation.

  18. Low temperature processing of ultra-pure cellulose fibers into nylon 6 and other thermoplastics

    Treesearch

    Rod Jacobson; Dan Caulfield; Karl Sears; John Underwood

    2002-01-01

    The objective of this research was to develop a stable process for compound ultra-pure cellulose fibers into polyamides. This has been a difficult procedure and has taken years of trial and error to understand the viscosity shear heating effects associated with compounding cellulose into high-melting point engineering thermoplastics. The evolution of the low...

  19. Molybdenum disulfide for ultra-low detection of free radicals: electrochemical response and molecular modeling

    NASA Astrophysics Data System (ADS)

    Gupta, Ankur; Rawal, Takat B.; Neal, Craig J.; Das, Soumen; Rahman, Talat S.; Seal, Sudipta

    2017-06-01

    Two-dimensional (2D) molybdenum disulfide (MoS2) offers attractive properties due to its band gap modulation and has led to significant research-oriented applications (i.e. DNA and protein detection, cell imaging (fluorescent label) etc.). In biology, detection of free radicals (i.e. reactive oxygen species and reactive nitrogen (NO*) species are very important for early discovery and treatment of diseases. Herein, for the first time, we demonstrate the ultra-low (pico-molar) detection of pharmaceutically relevant free radicals using MoS2 for electrochemical sensing. We present pico- to nano- molar level sensitivity in smaller MoS2 with S-deficiency as revealed by x-ray photoelectron spectroscopy. Furthermore, the detection mechanism and size-dependent sensitivity have been investigated by density functional theory (DFT) showing the change in electronic density of states of Mo atoms at edges which lead to the preferred adsorption of H2O2 on Mo edges. The DFT analysis signifies the role of size and S-deficiency in the higher catalytic activity of smaller MoS2 particles and, thus, ultra-low detection.

  20. Comparison of high-dose intermittent and low-dose continuous oral artemisinin in dogs with naturally occurring tumors.

    PubMed

    Hosoya, Kenji; Couto, C Guillermo; London, Cheryl A; Kisseberth, William C; Phelps, Mitchell A; Dalton, James T

    2014-01-01

    To evaluate the clinical toxicity and activity of orally administered artemisinin in dogs with spontaneous tumors, 24 client-owned dogs were randomly divided into two groups and received either low-continuous dose (3 mg/kg q 24 hr) or high-dose intermittent (three doses of 45 mg/kg q 6 hr repeated q 1 wk) of artemisinin per os. Treatment was continued for 21 days. Dogs were evaluated weekly for clinical effect and at the end of the treatment for hematologic and biochemical adverse events. Whole blood concentrations of artemisinin and dihydroartemisinin were measured by liquid chromatography/tandem mass spectrometry after the first dose of artemisinin in three dogs in each group. Blood concentrations of artemisinin and dihydroartemisinin were <0.1 μM at all time points, and there was no difference in blood concentration between the two dosing groups. The most frequent adverse event was anorexia, which was observed in 11% of the low-dose group and 29% of the high-dose group. Oral artemisinin, both in low-dose continuous and high-dose intermittent, is well tolerated in dogs but results in low bioavailability. Parenteral administration should be considered for future studies.