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Sample records for single oral dose

  1. Single oral dose safety of D-allulose in dogs

    PubMed Central

    NISHII, Naohito; NOMIZO, Toru; TAKASHIMA, Satoshi; MATSUBARA, Tatsuya; TOKUDA, Masaaki; KITAGAWA, Hitoshi

    2016-01-01

    Healthy dogs were administered acute oral doses of D-allulose (also called D-psicose) to evaluate its toxicity. Six dogs received oral doses of either a placebo or D-allulose solution (1 and 4 g/kg) on three different study days. One dog experienced vomiting, and five dogs showed transient diarrhea when 4 g/kg of D-allulose was administered. All dogs were active and had a good appetite throughout the study period. Blood glucose concentration slightly decreased without a rise in plasma insulin concentration 2 hr after D-allulose administration. Plasma alkaline phosphatase activities showed a mild increase between 12 and 48 hr after D-allulose administration. These data suggested that a single oral dose of D-allulose does not show severe toxicity in dogs. PMID:26972334

  2. Single-Dose Radiation-Induced Oral Mucositis Mouse Model

    PubMed Central

    Maria, Osama Muhammad; Syme, Alasdair; Eliopoulos, Nicoletta; Muanza, Thierry

    2016-01-01

    The generation of a self-resolved radiation-induced oral mucositis (RIOM) mouse model using the highest possibly tolerable single ionizing radiation (RT) dose was needed in order to study RIOM management solutions. We used 10-week-old male BALB/c mice with average weight of 23 g for model production. Mice were treated with an orthovoltage X-ray irradiator to induce the RIOM ulceration at the intermolar eminence of the animal tongue. General anesthesia was injected intraperitoneally for proper animal immobilization during the procedure. Ten days after irradiation, a single RT dose of 10, 15, 18, 20, and 25 Gy generated a RIOM ulcer at the intermolar eminence (posterior upper tongue surface) with mean ulcer floor (posterior epithelium) heights of 190, 150, 25, 10, and 10 μm, respectively, compared to 200 μm in non-irradiated animals. The mean RIOM ulcer size % of the total epithelialized upper surface of the animal tongue was RT dose dependent. At day 10, the ulcer size % was 2, 5, 27, and 31% for 15, 18, 20, and 25 Gy RT, respectively. The mean relative surface area of the total epithelialized upper surface of the tongue was RT dose dependent, since it was significantly decreased to 97, 95, 88, and 38% with 15, 18, 20, and 25 Gy doses, respectively, at day 10 after RT. Subcutaneous injection of 1 mL of 0.9% saline/6 h for 24 h yielded a 100% survival only with 18 Gy self-resolved RIOM, which had 5.6 ± 0.3 days ulcer duration. In conclusion, we have generated a 100% survival self-resolved single-dose RIOM male mouse model with long enough duration for application in RIOM management research. Oral mucositis ulceration was radiation dose dependent. Sufficient hydration of animals after radiation exposure significantly improved their survival. PMID:27446800

  3. Single-dose pharmacokinetics of oral fleroxacin in bacteremic patients.

    PubMed Central

    Schrenzel, J; Cerruti, F; Herrmann, M; Leemann, T; Weidekamm, E; Portmann, R; Hirschel, B; Lew, D P

    1994-01-01

    Fleroxacin is a new broad-spectrum quinolone which can be given by the oral route. The present study was designed to assess the influence of bacteremia on the pharmacokinetics of a single oral dose of fleroxacin. Thirteen patients with proven bacteremia (one or more pairs of positive blood cultures, no hypotension) were given a single 400-mg fleroxacin dose orally on two occasions while also receiving standard antibiotic therapy. The first dose was administered 12 to 36 h after the last positive blood culture was drawn (day 1), and a second dose was administered 7 days later (day 7 +/- 2) to compare the pharmacokinetics between the acute and the convalescent phases of the disease. Following each administration of fleroxacin, serial plasma samples were collected for up to 72 h and were analyzed for unchanged drug by a reversed phase high-pressure liquid chromatography technique. There were no significant changes in the following pharmacokinetic parameters (mean standard deviation) the maximum concentration of drug in serum (6.4 +/- 1.5 versus 6.7 +/- 1.9 mg/liter), the minimum concentration of drug in serum, defined as the concentration of drug in serum at 24 h postdose (3.0 +/- 1.7 versus 2.5 +/- 1.2 mg/liter), the time to the maximum concentration of drug in serum (2.3 +/- 1.4 versus 2.0 +/- 1.2 h), and the elimination half-life (19.7 +/- 8.0 versus 17.9 +/- 6.9 h). Fleroxacin clearances were compared for each individual patient. A positive correlation (R2 = 0.787) was found between the values measured on day 1 and day 7. Oral clearance of fleroxacin (CL = CL/F, where F is bioavailability was slightly, but not significantly, reduced during the bacteremic phase (oral clearance, 43.8+/- 23.5 versus 48.5 +/- 17.5 ml/min.). When compared with previous results obtained in healthy young subjects, longer times to the maximum concentration of drug in serum and elimination half-lives and higher areas under the curve were observed. This could be due to the bacteremic state

  4. Single dose oral paracetamol (acetaminophen) for postoperative pain in adults

    PubMed Central

    Toms, Laurence; McQuay, Henry J; Derry, Sheena; Moore, R Andrew

    2014-01-01

    Background This is an updated version of the original Cochrane review published in Issue 1, 2004 - this original review had been split from a previous title on ‘Single dose paracetamol (acetaminophen) with and without codeine for postoperative pain’. The last version of this review concluded that paracetamol is an effective analgesic for postoperative pain, but additional trials have since been published. This review sought to evaluate the efficacy and safety of paracetamol using current data, and to compare the findings with other analgesics evaluated in the same way. Objectives To assess the efficacy of single dose oral paracetamol for the treatment of acute postoperative pain. Search methods We searched The Cochrane Library, MEDLINE, EMBASE, the Oxford Pain Relief Database and reference lists of articles to update an existing version of the review in July 2008. Selection criteria Randomised, double-blind, placebo-controlled clinical trials of paracetamol for acute postoperative pain in adults. Data collection and analysis Two review authors independently assessed trial quality and extracted data. Area under the “pain relief versus time” curve was used to derive the proportion of participants with paracetamol or placebo experiencing at least 50% pain relief over four to six hours, using validated equations. Number-needed-to-treat-to-benefit (NNT) was calculated, with 95% confidence intervals (CI). The proportion of participants using rescue analgesia over a specified time period, and time to use, were sought as measures of duration of analgesia. Information on adverse events and withdrawals was also collected. Main results Fifty-one studies, with 5762 participants, were included: 3277 participants were treated with a single oral dose of paracetamol and 2425 with placebo. About half of participants treated with paracetamol at standard doses achieved at least 50% pain relief over four to six hours, compared with about 20% treated with placebo. NNTs for at

  5. Single dose oral flurbiprofen for acute postoperative pain in adults

    PubMed Central

    Sultan, Asquad; McQuay, Henry J; Moore, R Andrew; Derry, Sheena

    2014-01-01

    Background Flurbiprofen is a non-selective non-steroidal anti-inflammatory drug (NSAID), related to ibuprofen and naproxen, used to treat acute and chronic painful conditions. There is no systematic review of its use in acute postoperative pain. Objectives To assess efficacy, duration of action, and associated adverse events of single dose oral flurbiprofen in acute postoperative pain in adults. Search methods We searched Cochrane CENTRAL, MEDLINE, EMBASE and the Oxford Pain Relief Database for studies to January 2009. Selection criteria Randomised, double blind, placebo-controlled trials of single dose orally administered flurbiprofen in adults with moderate to severe acute postoperative pain. Data collection and analysis Two review authors independently assessed trial quality and extracted data. Pain relief or pain intensity data were extracted and converted into the dichotomous outcome of number of participants with at least 50% pain relief over 4 to 6 hours, from which relative risk (RR) and number needed to treat to benefit (NNT) were calculated. Numbers of participants using rescue medication over specified time periods, and time to use of rescue medication, were sought as additional measures of efficacy. Information on adverse events and withdrawals were collected. Main results Eleven studies compared flurbiprofen (699 participants) with placebo (362 participants) in studies lasting 6 to 12 hours. Studies were of adequate reporting quality, and most participants had pain following dental extractions. The dose of flurbiprofen used was 25 mg to 100 mg, with most information for 50 mg and 100 mg. The NNT for at least 50% pain relief over 4 to 6 hours for flurbiprofen 50 mg compared with placebo (692 participants) was 2.7 (2.3 to 3.3) and for 100 mg (416 participants) it was 2.5 (2.0 to 3.1). With flurbiprofen 50 mg and 100 mg 65% to 70% of participants experienced at least 50% pain relief, compared with 25% to 30% with placebo. Rescue medication was used by 25

  6. Single-dose oral guanidinoacetic acid exhibits dose-dependent pharmacokinetics in healthy volunteers.

    PubMed

    Ostojic, Sergej M; Vojvodic-Ostojic, Aleksandra

    2015-03-01

    Guanidinoacetic acid (GAA), the natural precursor of creatine, has potential as a dietary supplement for human nutrition, yet no data are available regarding its dose-dependent pharmacokinetic (PK) behavior. We hypothesized that a single dose of orally administered GAA exhibited dose-dependent PK behavior in healthy volunteers. Forty-eight young adults were enrolled in a randomized, placebo-controlled, double-blind, parallel-group trial to receive single oral doses of GAA (1.2, 2.4, and 4.8 g) or a placebo. Pharmacokinetic metrics for plasma GAA and creatine were assessed immediately before (0 hours) and at 1, 2, 4, 6, 8, 12, and 24 hours after GAA ingestion. The lag time appeared to be similar after the bolus ingestion of GAA (0.14 ± 0.17 hours for low-dose GAA, 0.31 ± 0.18 hours for medium-dose GAA, and 0.38 ± 0.32 hours for high-dose GAA; P = .05). An increase in the area under the concentration-time curve for plasma GAA was found for the dose range tested, with 2.4- and 9.3-fold increases in the area under the concentration-time curve for every 2-fold increase in the GAA dose (P < .0001). No differences were found for elimination half-time between the low-dose and medium-dose groups (<1.75 hours), whereas the elimination half-time was significantly longer (>2.1 hours) for the high-dose GAA regimen (P = .001). The volume of distribution was affected by the dosage of GAA applied (102.6 ± 17.3 L for low-dose GAA, 97.5 ± 15.7 L for medium-dose GAA, and 61.1 ± 12.7 L for high-dose GAA; P < .0001). Ingestion of GAA elevated plasma creatine by 80%, 116%, and 293% compared with the placebo for the 1.2, 2.4, and 4.8 g doses, respectively (P < .0001). Guanidinoacetic acid single-dose PK metrics were nonlinear with respect to dose size. Across the dose range of 1.2 to 4.8 g, systemic exposure to GAA increased in a greater than dose-proportional manner. PMID:25622538

  7. Biotransformation and pharmacokinetics of ethylmorphine after a single oral dose.

    PubMed Central

    Aasmundstad, T A; Xu, B Q; Johansson, I; Ripel, A; Bjørneboe, A; Christophersen, A S; Bodd, E; Mørland, J

    1995-01-01

    1. The pharmacokinetics of ethylmorphine after administration of a single dose of the cough mixture Cosylan were investigated in 10 healthy subjects. 2. The median urinary recovery of ethylmorphine and measured metabolites was 77% over 48 h. The median tmax of unchanged ethylmorphine was 45 min, and the terminal elimination t1/2 was 2 h. Ethylmorphine-6-glucuronide was found to be the major metabolite. 3. Two subjects had significantly lower urinary recovery (0.48 h) of morphine and morphine-glucuronides than the remainder. Furthermore, these two had urinary metabolic ratios (MRO) and partial metabolic clearances (CLmO) for O-deethylation of ethylmorphine tentatively classifying them phenotypically as poor metabolisers of the debrisoquine/sparteine type. 4. Genotyping for cytochrome P450 (CYP) 2D6 alleles revealed five homozygote (wt/wt) and five heterozygote subjects. Two subjects phenotypically classified as poor metabolisers were genotypically CYP2D6A/wt and CYP2D6D/wt, respectively. 5. Serum and urine samples taken more than 8 and 24 h after administration of ethyl-morphine respectively, contained morphine and morphine-glucuronides, but no ethylmorphine, ethylmorphine-6-glucuronide or (serum only) norethylmorphine. Norethylmorphine could be detected after hydrolysis of urine samples in all subjects. The urinary recovery of the active metabolites morphine and morphine-6-glucuronide after administration of ethylmorphine varied by a factor of 9 between individuals. 6. The wide variation in recovery of morphine and morphine-glucuronides after oral administration of ethylmorphine could not be explained simply by a difference in CYP2D6 genotype. Constitutional variation in other enzymatic pathways involved in ethylmorphine metabolism is probably crucial. Ratios of morphine to parent drug cannot be used to distinguish the source of morphine after administration of ethylmorphine. Norethylmorphine should be included in urine assays for opiates in forensic toxicology

  8. Pharmacokinetics of Memantine after a Single and Multiple Dose of Oral and Patch Administration in Rats.

    PubMed

    Lee, Soo-Han; Kim, Seung-Hyun; Noh, Yook-Hwan; Choi, Byung-Moon; Noh, Gyu-Jeong; Park, Woo-Dae; Kim, Eun-Jung; Cho, Ik-Hyun; Bae, Chun-Sik

    2016-02-01

    Memantine is a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist used to treat Alzheimer's disease. We investigated memantine pharmacokinetics after oral, IV and patch administration in rats, and compared memantine pharmacokinetics after multiple- or single-dose oral and transdermal administration. Venous blood was collected at preset intervals in single- and multiple-dose studies. Non-compartmental pharmacokinetics was analysed for all formulations. The oral, IV and patch memantine doses were 10 mg/kg, 2 mg/kg and 8.21 ± 0.89 mg/kg, respectively. The maximum plasma concentration was lower and the half-life longer after patch administration than oral and IV administration. Memantine bioavailability was 41 and 63% for oral and patch administration, respectively. Steady state was achieved around 24 hr for oral and patch administration. The mean AUC increased after oral or patch administration from single to multiple dose. The memantine patch formulation displayed a longer duration of action and lower peak plasma concentration. However, drug exposure was similar to the oral formulation at each dose. Additionally, the memantine patch formulation displayed a smaller interindividual variability and lower accumulation than the oral formulation.

  9. Pharmacokinetics of eltoprazine in healthy male subjects after single dose oral and intravenous administration.

    PubMed Central

    Raghoebar, M; Mak, M; Cournot, A; Pistorius, M C; Van Harten, J; Roseboom, H

    1990-01-01

    The kinetics, safety and tolerability of eltoprazine hydrochloride were studied in an open, cross-over, partially randomised design after single oral (8 mg) and intravenous (3 and 8 mg) doses to 12 healthy male subjects. After intravenous administration, the mean t1/2 ranged from 7 to 9 h, the MRT was 11 h, CL was 487 +/- 148 (3 mg dose) and 471 +/- 56 (8 mg dose) ml kg-1 h-1, while CLR was 226 +/- 124 (3 mg dose) and 189 +/- 38 (8 mg dose) ml kg-1 h-1. The Vss was 3.3 +/- 0.7 (3 mg dose) and 3.8 +/- 0.5 (8 mg dose) 1 kg-1. Cumulative renal excretion was 40%. The AUC and the cumulative urinary excretion were directly proportional to dose within the range of 3-8 mg. Values of tmax varied from 1 to 4 h after oral administration. The mean Cmax value was 24 ng ml-1 after an oral dose of 8 mg. The plasma elimination half-life after oral administration was 9.8 +/- 3.9 h. Absolute oral bioavailability was 110 +/- 32%. Dose-dependent somnolence was observed. PMID:2288834

  10. The treatment of pharyngeal gonorrhoea with a single oral dose of cefixime.

    PubMed

    McMillan, A; Young, H

    2007-04-01

    An audit of the efficacy treatment of pharyngeal gonorrhoea with a single oral dose of 400 mg of cefixime was undertaken; 83% of patients also received a single oral dose of azithromycin to treat possible concurrent anogenital chlamydial infection. Of the 54 patients studied, only one of 45 patients who attended for at least one test of cure had a positive culture seven days after treatment; the possibility of reinfection could not have been excluded. Two tests of cure were obtained from 18 patients. Cefixime, therefore, seems to be effective in the treatment of pharyngeal gonorrhoea.

  11. Prescription Opioids. IV: Disposition of Hydrocodone in Oral Fluid and Blood Following Single-Dose Administration.

    PubMed

    Cone, Edward J; DePriest, Anne Z; Heltsley, Rebecca; Black, David L; Mitchell, John M; LoDico, Charles; Flegel, Ron

    2015-09-01

    The Substance Abuse and Mental Health Services Administration (SAMHSA) is currently evaluating hydrocodone (HC) for inclusion in the Mandatory Guidelines for Federal Workplace Drug Testing Programs. This study evaluated the time course of HC, norhydrocodone (NHC), dihydrocodeine (DHC) and hydromorphone (HM) in paired oral fluid and whole blood specimens by liquid chromatography-tandem mass spectrometry (limit of quantitation = 1 ng/mL of oral fluid, 5 ng/mL of blood) over a 52-h period. A single dose of HC bitartrate, 20 mg, was administered to 12 subjects. Analyte prevalence was as follows: oral fluid, HC > NHC > DHC; and blood, HC > NHC. HM was not detected in any specimen. HC was frequently detected within 15 min in oral fluid and 30 min in blood. Mean oral fluid to blood (OF : BL) ratios and correlations were 3.2 for HC (r = 0.73) and 0.7 for NHC (r = 0.42). The period of detection for oral fluid exceeded blood at all evaluated thresholds. At a 1-ng/mL threshold for oral fluid, mean detection time was 30 h for HC and 18 h for NHC and DHC. This description of HC and metabolite disposition in oral fluid following single-dose administration provides valuable interpretive guidance of HC test results.

  12. Prescription Opioids. IV: Disposition of Hydrocodone in Oral Fluid and Blood Following Single-Dose Administration.

    PubMed

    Cone, Edward J; DePriest, Anne Z; Heltsley, Rebecca; Black, David L; Mitchell, John M; LoDico, Charles; Flegel, Ron

    2015-09-01

    The Substance Abuse and Mental Health Services Administration (SAMHSA) is currently evaluating hydrocodone (HC) for inclusion in the Mandatory Guidelines for Federal Workplace Drug Testing Programs. This study evaluated the time course of HC, norhydrocodone (NHC), dihydrocodeine (DHC) and hydromorphone (HM) in paired oral fluid and whole blood specimens by liquid chromatography-tandem mass spectrometry (limit of quantitation = 1 ng/mL of oral fluid, 5 ng/mL of blood) over a 52-h period. A single dose of HC bitartrate, 20 mg, was administered to 12 subjects. Analyte prevalence was as follows: oral fluid, HC > NHC > DHC; and blood, HC > NHC. HM was not detected in any specimen. HC was frequently detected within 15 min in oral fluid and 30 min in blood. Mean oral fluid to blood (OF : BL) ratios and correlations were 3.2 for HC (r = 0.73) and 0.7 for NHC (r = 0.42). The period of detection for oral fluid exceeded blood at all evaluated thresholds. At a 1-ng/mL threshold for oral fluid, mean detection time was 30 h for HC and 18 h for NHC and DHC. This description of HC and metabolite disposition in oral fluid following single-dose administration provides valuable interpretive guidance of HC test results. PMID:25962610

  13. Single intravenous and oral dose pharmacokinetics of florfenicol in the channel catfish Ictalurus punctatus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plasma distribution and elimination of florfenicol in channel catfish were investigated after a single dose (10mg/kg) of intravenous i.v.) or oral administration in freshwater at a mean water temperature of 25.4°C. Florfenicol concentrations in plasma were analyzed by means of liquid chromatography...

  14. The effect of a single oral dose of pergolide on intraocular pressure and pupil diameter.

    PubMed Central

    al-Sereiti, M R; Quik, R F; Turner, P

    1989-01-01

    1. The ocular hypotensive effect of a single oral dose of 25 micrograms pergolide, a dopamine 2-receptor agonist, was studied in 12 normal human volunteers, using a non-invasive method. 2. An oral dose of timolol 20 mg was used as a positive control. 3. The effects of both drugs on pupil diameter were also studied, using a photographic method. 4. Considering the first 6 h post-dosing measurements, using multiple linear regression analysis comparing drug with placebo and including the baseline values as continuous independent variables, both pergolide and timolol had a significant ocular hypotensive effect in both eyes (P less than 0.0001) with no significant effects on pupil diameter. 5. Further topical application studies in normal and glaucomatous eyes are needed to evaluate the usefulness of pergolide in the treatment of glaucoma. PMID:2789919

  15. Miltefosine Lipid Nanocapsules for Single Dose Oral Treatment of Schistosomiasis Mansoni: A Preclinical Study

    PubMed Central

    Eissa, Maha M.; El-Moslemany, Riham M.; Ramadan, Alyaa A.; Amer, Eglal I.; El-Azzouni, Mervat Z.; El-Khordagui, Labiba K.

    2015-01-01

    Miltefosine (MFS) is an alkylphosphocholine used for the local treatment of cutaneous metastases of breast cancer and oral therapy of visceral leishmaniasis. Recently, the drug was reported in in vitro and preclinical studies to exert significant activity against different developmental stages of schistosomiasis mansoni, a widespread chronic neglected tropical disease (NTD). This justified MFS repurposing as a potential antischistosomal drug. However, five consecutive daily 20 mg/kg doses were needed for the treatment of schistosomiasis mansoni in mice. The present study aims at enhancing MFS efficacy to allow for a single 20mg/kg oral dose therapy using a nanotechnological approach based on lipid nanocapsules (LNCs) as oral nanovectors. MFS was incorporated in LNCs both as membrane-active structural alkylphospholipid component and active antischistosomal agent. MFS-LNC formulations showed high entrapment efficiency (EE%), good colloidal properties, sustained release pattern and physical stability. Further, LNCs generally decreased MFS-induced erythrocyte hemolytic activity used as surrogate indicator of membrane activity. While MFS-free LNCs exerted no antischistosomal effect, statistically significant enhancement was observed with all MFS-LNC formulations. A maximum effect was achieved with MFS-LNCs incorporating CTAB as positive charge imparting agent or oleic acid as membrane permeabilizer. Reduction of worm load, ameliorated liver pathology and extensive damage of the worm tegument provided evidence for formulation-related efficacy enhancement. Non-compartmental analysis of pharmacokinetic data obtained in rats indicated independence of antischistosomal activity on systemic drug exposure, suggesting possible gut uptake of the stable LNCs and targeting of the fluke tegument which was verified by SEM. The study findings put forward MFS-LNCs as unique oral nanovectors combining the bioactivity of MFS and biopharmaceutical advantages of LNCs, allowing targeting

  16. PHARMACOKINETICS OF SINGLE-DOSE ORALLY ADMINISTERED CIPROFLOXACIN IN CALIFORNIA SEA LIONS (ZALOPHUS CALIFORNIANUS).

    PubMed

    Barbosa, Lorraine; Johnson, Shawn P; Papich, Mark G; Gulland, Frances

    2015-06-01

    Ciprofloxacin is commonly selected for clinical use due to its broad-spectrum efficacy and is a frequently administered antibiotic at The Marine Mammal Center, a marine mammal rehabilitation facility. Ciprofloxacin is used for treatment of California sea lions ( Zalophus californianus ) suffering from a variety of bacterial infections at doses extrapolated from other mammalian species. However, as oral absorption is variable both within and across species, a more accurate determination of appropriate dosage is needed to ensure effective treatment and avoid emergence of drug-resistant bacterial strains. A pharmacokinetic study was performed to assess plasma concentrations of ciprofloxacin in California sea lions after a single oral dose. Twenty healthy California sea lions received a single 10-mg/kg oral dose of ciprofloxacin administered in a herring fish. Blood was then collected at two of the following times from each individual: 0.5, 0.75, 1, 2, 4, 8, 10, 12, 18, and 24 hr postingestion. Plasma ciprofloxacin concentration was assessed via high-performance liquid chromatography. A population pharmacokinetics model demonstrated that an oral ciprofloxacin dose of 10 mg/kg achieved an area under the concentration vs. time curve of 6.01 μg hr/ml. Absorption was rapid, with ciprofloxacin detectable in plasma 0.54 hr after drug administration; absorption half-life was 0.09 hr. A maximum plasma concentration of 1.21 μg/ml was observed at 1.01 hr, with an elimination half-life of 3.09 hr. Ciprofloxacin administered orally at 10 mg/kg produced therapeutic antibacterial exposure for only some of the most susceptible bacterial organisms commonly isolated from California sea lions. PMID:26056878

  17. PHARMACOKINETICS OF SINGLE-DOSE ORALLY ADMINISTERED CIPROFLOXACIN IN CALIFORNIA SEA LIONS (ZALOPHUS CALIFORNIANUS).

    PubMed

    Barbosa, Lorraine; Johnson, Shawn P; Papich, Mark G; Gulland, Frances

    2015-06-01

    Ciprofloxacin is commonly selected for clinical use due to its broad-spectrum efficacy and is a frequently administered antibiotic at The Marine Mammal Center, a marine mammal rehabilitation facility. Ciprofloxacin is used for treatment of California sea lions ( Zalophus californianus ) suffering from a variety of bacterial infections at doses extrapolated from other mammalian species. However, as oral absorption is variable both within and across species, a more accurate determination of appropriate dosage is needed to ensure effective treatment and avoid emergence of drug-resistant bacterial strains. A pharmacokinetic study was performed to assess plasma concentrations of ciprofloxacin in California sea lions after a single oral dose. Twenty healthy California sea lions received a single 10-mg/kg oral dose of ciprofloxacin administered in a herring fish. Blood was then collected at two of the following times from each individual: 0.5, 0.75, 1, 2, 4, 8, 10, 12, 18, and 24 hr postingestion. Plasma ciprofloxacin concentration was assessed via high-performance liquid chromatography. A population pharmacokinetics model demonstrated that an oral ciprofloxacin dose of 10 mg/kg achieved an area under the concentration vs. time curve of 6.01 μg hr/ml. Absorption was rapid, with ciprofloxacin detectable in plasma 0.54 hr after drug administration; absorption half-life was 0.09 hr. A maximum plasma concentration of 1.21 μg/ml was observed at 1.01 hr, with an elimination half-life of 3.09 hr. Ciprofloxacin administered orally at 10 mg/kg produced therapeutic antibacterial exposure for only some of the most susceptible bacterial organisms commonly isolated from California sea lions.

  18. Guaifenesin Pharmacokinetics Following Single-Dose Oral Administration in Children Aged 2 to 17 Years.

    PubMed

    Thompson, Gary A; Solomon, Gail; Albrecht, Helmut H; Reitberg, Donald P; Guenin, Eric

    2016-07-01

    This study characterized guaifenesin pharmacokinetics in children aged 2 to 17 years (n = 40) who received a single oral dose of guaifenesin (age-based doses of 100-400 mg) 2 hours after breakfast. Plasma samples were obtained before and for 8 hours after dosing and analyzed for guaifenesin using liquid chromatography-tandem mass spectrometry. Pharmacokinetic parameters were estimated using noncompartmental methods, relationships with age were assessed using linear regression, and dose proportionality was assessed on 95% confidence intervals. Based on the upper dose recommended in the monograph (for both children and adolescents), area under the curve from time zero to infinity and maximum plasma concentration both increased with age. However, when comparing the upper dose for children aged 2 to 11 years with the lower dose for adolescents aged 12 to 17 years, similar systemic exposure was observed. As expected due to increasing body size, oral clearance (CLo ) and terminal volume of distribution (Vz /F) increased with age. Due to a larger increase in Vz /F than CLo , an increase in terminal exponential half-life was also observed. Allometric scaling indicated no maturation-related changes in CLo and Vz /F. PMID:26632082

  19. Single dose intravenous methyl prednisolone versus oral prednisolone in Bell's palsy: A randomized controlled trial

    PubMed Central

    Giri, Prithvi; Garg, Ravindra Kumar; Singh, Maneesh Kumar; Verma, Rajesh; Malhotra, Hardeep Singh; Sharma, Praveen Kumar

    2015-01-01

    Objectives: Corticosteroids have been used in the treatment of Bell's palsy and several other postinfectious neurological conditions. We hypothesized that administration of a single dose of intravenous (IV) methylprednisolone might be an effective alternative to oral prednisolone. Materials and Methods: In this open label, randomized trial, patients with acute Bell's palsy were randomized into two groups. One group received single dose (500 mg) of IV methylprednisolone while the other group received 10 days of oral prednisone. Outcome was assessed at 1 and 3 months with House–Brackmann scale. Results: At 3 months, 93 (79.48%) patients had completely recovered. IV methylprednisolone and oral prednisolone groups had similar recovery rates (80% vs. 78.33%, P > 0.05). Patients with Grade 2 and 3 recovered completely. In patients with Grade 6, the recovery rate was 20%. A better outcome was observed if corticosteroids were administered within 3 days of onset of palsy. Conclusion: Intravenous methylprednisolone and oral prednisolone showed equivalent benefit in patients with acute Bell's palsy. PMID:25878371

  20. Evidence for CVD 103-HgR as an effective single-dose oral cholera vaccine.

    PubMed

    Jackson, Sarah S; Chen, Wilbur H

    2015-01-01

    We propose the ideal oral cholera vaccine (OCV) should be an inexpensive, single, oral dose that rapidly confers immunity for a long duration, and is well tolerated by individuals vulnerable to cholera. Vaccine trials in industrialized countries of a single oral dose of 5 × 10(8) colony forming units (CFU) of the live, attenuated cholera strain CVD 103-HgR have shown 88-97% serum vibriocidal antibody seroconversion rates, a correlate of protection and documented vaccine efficacy of ≥80% using volunteer challenge studies with wild-type cholera. For individuals of developing countries, a 5 × 10(9) CFU dose of CVD 103-HgR is necessary to elicit similar antibody responses. Presently, a reformulation of CVD 103-HgR is in late-stage clinical development for prospective US FDA licensure; making a cholera vaccine for US travelers potentially accessible in 2016. The availability of CVD 103-HgR should be a welcome addition to the currently available OCVs.

  1. Evidence for CVD 103-HgR as an effective single-dose oral cholera vaccine.

    PubMed

    Jackson, Sarah S; Chen, Wilbur H

    2015-01-01

    We propose the ideal oral cholera vaccine (OCV) should be an inexpensive, single, oral dose that rapidly confers immunity for a long duration, and is well tolerated by individuals vulnerable to cholera. Vaccine trials in industrialized countries of a single oral dose of 5 × 10(8) colony forming units (CFU) of the live, attenuated cholera strain CVD 103-HgR have shown 88-97% serum vibriocidal antibody seroconversion rates, a correlate of protection and documented vaccine efficacy of ≥80% using volunteer challenge studies with wild-type cholera. For individuals of developing countries, a 5 × 10(9) CFU dose of CVD 103-HgR is necessary to elicit similar antibody responses. Presently, a reformulation of CVD 103-HgR is in late-stage clinical development for prospective US FDA licensure; making a cholera vaccine for US travelers potentially accessible in 2016. The availability of CVD 103-HgR should be a welcome addition to the currently available OCVs. PMID:26228388

  2. Effect of single oral dose of tramadol on gastric secretions pH

    PubMed Central

    Ullah, Khan Mueen; Aqil, Mansoor; Hussain, Altaf; Al Zahrani, Tariq; Hillis, Marwan

    2015-01-01

    Background: Tramadol is an atypical analgesic agent. It has been shown that intramuscular or intravenous injection tramadol is able to inhibit M3 muscarinic receptors. Tramadol is able to mediate smooth muscles contraction and glandular secretions. We have evaluated the effects of single oral dose of tramadol given preoperatively on gastric juices pH in patients electively scheduled for laparoscopic cholecystectomy. Materials and Methods: Sixty adult, American Society of Anesthesiologist I and II patients scheduled for laparoscopic cholecystectomy were included in the study. Patients were randomly assigned to receive either placebo (n = 30) or oral tramadol 50 mg (n = 30). General anesthesia was induced using propofol, fentanyl and cisatracurium. After induction of anesthesia 5 ml of gastric fluid was aspirated through orogastric tube. The gastric fluid pH was measured using pH meter. Result: There was no significant difference in the pH between the groups. Gastric pH of the placebo and tramadol groups was 1.97 versus 1.98 (P = 0.092) respectively. Conclusion: Preoperatively single oral dose of tramadol was unable to elevate the desired level of gastric acid secretions pH (>2.5). This may be due to pharmacokinetic disparity between the analgesic and pH elevating properties of tramadol. PMID:25558191

  3. Efficacy of a single oral dose of oxfendazole against Fasciola hepatica in naturally infected sheep.

    PubMed

    Gomez-Puerta, Luis A; Gavidia, Cesar; Lopez-Urbina, Maria T; Garcia, Hector H; Gonzalez, Armando E

    2012-03-01

    The efficacy of a single oral dose of 30 mg/kg of oxfendazole against Fasciola hepatica was evaluated in a controlled study in naturally infected sheep. Sheep were diagnosed by stool microscopy after sedimentation, and positive animals were randomized to oxfendazole (N = 20) or no treatment (N = 20). A new stool exam was performed 10 days after treatment. All stool microscopies were performed masked to the treatment group. No side effects were noticed. All sheep in the control group remained infected with similar counts of eggs per gram of stools. None of the animals in the treatment group showed Fasciola eggs in stools after 10 days of treatment. A single dose of oxfendazole is highly effective against F. hepatica, providing a new drug alternative for the control of fascioliasis or integrated zoonosis control.

  4. Efficacy of a Single Oral Dose of Oxfendazole against Fasciola hepatica in Naturally Infected Sheep

    PubMed Central

    Gomez-Puerta, Luis A.; Gavidia, Cesar; Lopez-Urbina, Maria T.; Garcia, Hector H.; Gonzalez, Armando E.

    2012-01-01

    The efficacy of a single oral dose of 30 mg/kg of oxfendazole against Fasciola hepatica was evaluated in a controlled study in naturally infected sheep. Sheep were diagnosed by stool microscopy after sedimentation, and positive animals were randomized to oxfendazole (N = 20) or no treatment (N = 20). A new stool exam was performed 10 days after treatment. All stool microscopies were performed masked to the treatment group. No side effects were noticed. All sheep in the control group remained infected with similar counts of eggs per gram of stools. None of the animals in the treatment group showed Fasciola eggs in stools after 10 days of treatment. A single dose of oxfendazole is highly effective against F. hepatica, providing a new drug alternative for the control of fascioliasis or integrated zoonosis control. PMID:22403323

  5. Pharmacokinetics of marbofloxacin after a single oral dose to loggerhead sea turtles (Caretta caretta).

    PubMed

    Marín, P; Lai, O R; Laricchiuta, P; Marzano, G; Di Bello, A; Cárceles, C M; Crescenzo, G

    2009-10-01

    The single-dose disposition kinetics of marbofloxacin (MBX) were determined in clinically healthy loggerhead sea turtles (n=5) after oral (PO) administration of 2 mg kg(-1) bodyweight. Marbofloxacin plasma concentrations were determined by DAD-HPLC (LOD/LOQ 0.015/0.05 microg ml(-1)). Data were subjected to non-compartmental analysis. Following PO administration, marbofloxacin achieved maximum plasma concentrations of 11.66+/-2.53 mg L(-1) at 15.00+/-3.00 h. The absence of general adverse reactions in the turtles of the study, and the favourable pharmacokinetic properties (long half-life and high maximum plasma concentration) of MBX administered PO at the single-dose of 2 mg kg(-1) suggest the possibility of its safe and effective clinical use in loggerhead sea turtles.

  6. Comparative disposition of codeine and pholcodine in man after single oral doses.

    PubMed Central

    Findlay, J W; Fowle, A S; Butz, R F; Jones, E C; Weatherley, B C; Welch, R M; Posner, J

    1986-01-01

    Four healthy male subjects received single oral doses of 15, 30 and 60 mg of codeine and pholcodine according to a balanced cross-over design with an interval of 7 days between the six treatments. Blood samples were collected for 8 h after each drug administration. In phase 2 of the study six different male volunteers received single oral doses of 60 mg of codeine and pholcodine with a 14 day interval between successive drug treatments. Blood was sampled for 12 h after codeine and 121 h after pholcodine administration. Plasma concentrations of free (unconjugated) and total (unconjugated plus conjugated) codeine, pholcodine and morphine were determined by radioimmunoassay and selected pharmacokinetic parameters were derived from these data. Pharmacokinetics of both drugs were independent of dose. Codeine was absorbed and eliminated relatively rapidly [elimination t1/2 = 2.3 +/- 0.4 h (mean +/- s.d.)]. While codeine kinetics were adequately described by a one-compartment open model with first-order absorption, a two-compartment model was required to describe pholcodine elimination from plasma (t1/2,z = 37.0 +/- 4.2 h). Plasma concentrations of conjugated codeine were much greater than those of the unconjugated alkaloid. By contrast, pholcodine appeared to undergo little conjugation. Biotransformation of codeine to morphine was evident in all subjects, although the extent of this metabolic conversion varied considerably between subjects. Morphine was not detectable in the plasma of any subject after pholcodine administration. PMID:3741728

  7. Oral testosterone-triglyceride conjugate in rabbits: single-dose pharmacokinetics and comparison with oral testosterone undecanoate.

    PubMed

    Amory, J K; Scriba, G K E; Amory, D W; Bremner, W J

    2003-01-01

    Development of a safe and effective oral form of testosterone has been inhibited by the rapid hepatic metabolism of nonalkylated androgens. Since triglycerides are absorbed via lymphatics and bypass the liver, we hypothesized that a testosterone-triglyceride conjugate (TTC) might allow for safe and effective oral testosterone therapy. Therefore, we studied the single-dose pharmacokinetics of oral administration of TTC in rabbits. Female New Zealand rabbits were administered 2, 4, or 8 mg/kg of TTC in sesame oil by gastric lavage. Testosterone undecanoate (TU) by gastric lavage was used as a positive control. Blood was sampled from a catheter in the auricular artery at 0, 15, 30, 60, 90, 120, 180, 240, 360, 480, and 600 minutes after drug administration. Samples were assayed for testosterone by a fluoroimmunoassay. Mean serum testosterone, area under the curve (AUC), and terminal half-life were calculated. Oral TTC administration resulted in rapid and marked increases in serum testosterone. Oral TTC resulted in higher maximum serum testosterone concentrations than oral TU at 8 mg/kg (TTC: 28.6 +/- 7.9 nmol/L vs TU: 11.9 +/- 2.1 nmol/L; P <.001) and 4 mg/kg (TTC: 11.5 +/- 4.2 nmol/L vs TU: 3.6 +/- 1.0 nmol/L; P <.001). In addition, the AUC was 1.8 to 2.6 times greater for TTC than TU at both doses (P <.05). The terminal half-life for both TU and TTC was between 3 and 5 hours and was not significantly different. We conclude that oral TTC is rapidly absorbed from the rabbit intestine and results in elevated concentrations of serum testosterone. The absorption of TTC appears to be superior to that of TU; however, the in vivo persistence of the 2 compounds is similar. TTC may offer an alternative to the use of TU for oral testosterone therapy. Further testing of this compound is warranted. PMID:12954663

  8. Ivermectin effect on microfilariae of Onchocerca volvulus after a single oral dose in humans.

    PubMed

    Soboslay, P T; Newland, H S; White, A T; Erttmann, K D; Albiez, E J; Taylor, H R; Williams, P N; Greene, B M

    1987-03-01

    Ivermectin is a broad spectrum anti-helminthic agent which is currently being tested for use in human onchocerciasis. Its activity is believed to result from its effect on GABA-mediated neurotransmission. We examined the effects of ivermectin on motility of microfilariae of O. volvulus following administration to humans. When ivermectin was given in dosages of 100, 150 and 200 mcg/kg on day 1 there was a clear reduction in motility of microfilariae obtained on day 3 when compared to microfilariae from the placebo group. The mean motility scores in microfilariae from ivermectin recipients were 3.1, 2.3, and 2.2 at 0, 12, and 24 hours of incubation compared to 3.3, 2.9, and 2.5, respectively, in microfilariae from placebo recipients (p less than 0.003, p less than 0.005, and p less than 0.012, respectively). Examination of the effect according to dose suggested a dose-response relationship. Microfilariae in the anterior chamber of the eye 2 days after a single oral dose of ivermectin showed abnormal and reduced winding and coiling. Microfilariae in 50% of ivermectin recipients showed abnormal motility compared to no such effects in subjects examined concurrently who received oral DEC, DEC lotion or placebo. These observations indicate that ivermectin has an effect on motility of microfilariae of O. volvulus following administration to humans.

  9. Single dose oral mefenamic acid for acute postoperative pain in adults

    PubMed Central

    Moll, Rachel; Derry, Sheena; Moore, R Andrew; McQuay, Henry J

    2014-01-01

    Background Mefenamic acid is a non-steroidal anti-inflammatory drug (NSAID). It is most often used for treating pain of dysmenorrhoea in the short term (seven days or less), as well as mild to moderate pain including headache, dental pain, postoperative and postpartum pain. It is widely available in many countries worldwide. Objectives To assess the efficacy of single dose oral mefenamic acid in acute postoperative pain, and any associated adverse events. Search methods We searched Cochrane CENTRAL, MEDLINE, EMBASE and the Oxford Pain Relief Database for studies to December 2010. Selection criteria Single oral dose, randomised, double-blind, placebo-controlled trials of mefenamic acid for relief of established moderate to severe postoperative pain in adults. Data collection and analysis Studies were assessed for methodological quality and the data extracted by two review authors independently. Summed total pain relief (TOTPAR) or pain intensity difference (SPID) over 4 to 6 hours was used to calculate the number of participants achieving at least 50% pain relief. These derived results were used to calculate, with 95% confidence intervals, the relative benefit compared to placebo, and the number needed to treat (NNT) for one participant to experience at least 50% pain relief over 4 to 6 hours. Numbers of participants using rescue medication over specified time periods, and time to use of rescue medication, were sought as additional measures of efficacy. Information on adverse events and withdrawals was collected. Main results Four studies with 842 participants met the inclusion criteria; 126 participants were treated with mefenamic acid 500 mg, 67 with mefenamic acid 250 mg, 197 with placebo, and 452 with lignocaine, aspirin, zomepirac or nimesulide. Participants had pain following third molar extraction, episiotomy and orthopaedic surgery. The NNT for at least 50% pain relief over 6 hours with a single dose of mefenamic acid 500 mg compared to placebo was 4.0 (2

  10. Successful comeback of the single-dose live oral cholera vaccine CVD 103-HgR.

    PubMed

    Herzog, Christian

    2016-01-01

    Effective and easy to administer cholera vaccines are in need more than ever, for at risk populations and travellers alike. In many parts of the world cholera is still endemic, causing outbreaks and constituting repeatedly serious public health problems. The oral live cholera vaccine CVD 103-HgR (Orochol, Mutachol), the first genetically modified organism (GMO) used as vaccine, was in its time (launched 1993, Switzerland) the ideal cholera vaccine: single-dose, protective efficacy of 80-100% against moderate to severe cholera, acting within 8 days and exhibiting excellent safety, indiscernible from placebo. However, there were strong headwinds: In the 1990s the indication for cholera vaccines was generally downplayed by experts and in 1997 the European Commission called for a moratorium of GMOs which blocked the registration in the European Union. Thus, demand for this vaccine remained low and in 2003 it was taken off the market for economic reasons. After a decade in obscurity it (Vaxchora) has resurfaced again, now produced in the U.S. and equipped with a U.S. FDA license (June 10, 2016). What had happened? This commentary gives a critical account of an almost unbelievable string of misadventures, emerging adverse circumstances and man-made failures which nearly killed this single-dose live oral cholera vaccine. The good news is that patience and persistence lead to success in the end, allowing good science to prevail for the benefit of those in need. PMID:27425792

  11. Successful comeback of the single-dose live oral cholera vaccine CVD 103-HgR.

    PubMed

    Herzog, Christian

    2016-01-01

    Effective and easy to administer cholera vaccines are in need more than ever, for at risk populations and travellers alike. In many parts of the world cholera is still endemic, causing outbreaks and constituting repeatedly serious public health problems. The oral live cholera vaccine CVD 103-HgR (Orochol, Mutachol), the first genetically modified organism (GMO) used as vaccine, was in its time (launched 1993, Switzerland) the ideal cholera vaccine: single-dose, protective efficacy of 80-100% against moderate to severe cholera, acting within 8 days and exhibiting excellent safety, indiscernible from placebo. However, there were strong headwinds: In the 1990s the indication for cholera vaccines was generally downplayed by experts and in 1997 the European Commission called for a moratorium of GMOs which blocked the registration in the European Union. Thus, demand for this vaccine remained low and in 2003 it was taken off the market for economic reasons. After a decade in obscurity it (Vaxchora) has resurfaced again, now produced in the U.S. and equipped with a U.S. FDA license (June 10, 2016). What had happened? This commentary gives a critical account of an almost unbelievable string of misadventures, emerging adverse circumstances and man-made failures which nearly killed this single-dose live oral cholera vaccine. The good news is that patience and persistence lead to success in the end, allowing good science to prevail for the benefit of those in need.

  12. Significant Increase in Salivary Substance P Level after a Single Oral Dose of Cevimeline in Humans

    PubMed Central

    Suzuki, Yosuke; Itoh, Hiroki; Amada, Kohei; Yamamura, Ryota; Sato, Yuhki; Takeyama, Masaharu

    2013-01-01

    Cevimeline is a novel muscarinic acetylcholine receptor agonist currently being developed as a therapeutic agent for xerostomia. We examined the effects of cevimeline on salivary and plasma levels of substance-P- (SP-), calcitonin-gene-related-peptide- (CGRP-), and vasoactive-intestinal-polypeptide- (VIP-) like immunoreactive substances (ISs) in humans. An open-labeled crossover study was conducted on seven healthy volunteers. Saliva volume was measured, and saliva and venous blood samples were collected before and 30–240 min after a single oral dose of cevimeline or placebo. Salivary and plasma levels of SP-, CGRP-, and VIP-IS were measured using a highly sensitive enzyme immunoassay. A single oral dose of cevimeline resulted in significant increases in salivary but not plasma SP-IS level compared to placebo. Cevimeline administration did not alter the salivary or plasma levels of CGRP-IS or VIP-IS compared to placebo. Significant increases in salivary volume were observed after cevimeline administration compared to placebo. A significant correlation was observed between the total release of SP-IS and that of salivary volume. These findings suggest an association of SP with the enhancement of salivary secretion by cevimeline. PMID:23589717

  13. Toxicokinetics of acrylamide in rats and humans following single oral administration of low doses

    SciTech Connect

    Kopp, Eva Katharina; Dekant, Wolfgang

    2009-03-01

    The rodent carcinogen acrylamide (AA) is formed during preparation of starch-containing foods. AA is partly metabolized to the genotoxic epoxide glycidamide (GA). After metabolic processing, the mercapturic acids N-acetyl-S-(2-carbamoylethyl)-L-cysteine (AAMA), rac-N-acetyl-S-(2-carbamoyl-2-hydroxyethyl)-L-cysteine (GAMA) and rac-N-acetyl-S-(1-carbamoyl-moyl-2-hydroxyethyl)-L-cysteine (iso-GAMA) are excreted with urine. In humans, AAMA can be sulfoxidized to AAMA-sulfoxide. The aim of this study was to assess potential species-differences in AA-toxicokinetics in rats and humans after single oral administration of doses similar to the daily human dietary exposure. Male Fischer 344 rats (n = 5/dose group) were administered 20 and 100 {mu}g/kg b.w. {sup 13}C{sub 3}-AA in deionized water via oral gavage. Human subjects (n = 3/gender) were orally administered 0.5 and 20 {mu}g/kg b.w. {sup 13}C{sub 3}-AA with drinking water. Urine samples were collected in intervals for 96 and 94 h, respectively. Urinary concentrations of {sup 13}C{sub 3}-AAMA, {sup 13}C{sub 3}-GAMA and {sup 13}C{sub 3}-AAMA-sulfoxide were monitored by liquid chromatography-tandem mass spectrometry. The recovered urinary metabolites accounted for 66.3% and 70.5% of the 20 and 100 {mu}g/kg b.w. doses in rats and for 71.3% and 70.0% of the 0.5 and 20 {mu}g/kg b.w. doses in humans. In rats, {sup 13}C{sub 3}-AAMA accounted for 33.6% and 38.8% of dose and 32.7% and 31.7% of dose was recovered as {sup 13}C{sub 3}-GAMA; {sup 13}C{sub 3}-AAMA-sulfoxide was not detected in rat urine. In humans, {sup 13}C{sub 3}-AAMA, {sup 13}C{sub 3}-GAMA and {sup 13}C{sub 3}-AAMA-sulfoxide accounted for 51.7% and 49.2%, 6.3% and 6.4% and 13.2% and 14.5% of the applied dose, respectively. The obtained results suggest that the extent of AA bioactivation to GA in humans is lower than in rodents.

  14. Pharmacokinetics of Single- and Multiple-Dose Oral Clarithromycin in Soft Tissues Determined by Microdialysis▿

    PubMed Central

    Traunmüller, Friederike; Zeitlinger, Markus; Zeleny, Petra; Müller, Markus; Joukhadar, Christian

    2007-01-01

    The antimicrobial spectrum of clarithromycin renders this antibiotic a frequently used option in the treatment of skin and soft-tissue infections. In most cases, these infections are caused by extracellularly proliferating microorganisms. Thus, clarithromycin concentrations achieved in the interstitial space are considered particularly important for clinical efficacy. In the present study, clarithromycin concentrations in plasma and interstitial-space fluid of subcutaneous adipose tissue and skeletal muscle of six healthy male volunteers were assessed by means of the microdialysis technique after oral single-dose administration of 250 mg and multiple doses of 500 mg of clarithromycin twice a day (b.i.d.). The ratios of the area under the concentration-time curve of free clarithromycin from 0 to 24 h calculated for a single dose of 250 mg (fAUC0-24) in interstitial-space fluid to the fAUC0-24 in plasma were 0.29 ± 0.17 and 0.42 ± 0.18 for subcutis and skeletal muscle, respectively. For 500 mg of clarithromycin at the steady state (3 to 5 days of intake twice daily), the fAUC0-24(b.i.d.) ratios at the steady state were 0.39 ± 0.04 and 0.41 ± 0.19 for subcutis and skeletal muscle, respectively. The half-life was around 2 h after a single dose but increased to approximately 4 h in plasma and tissues after repetitive clarithromycin administration. Based on subsequently performed pharmacokinetic-pharmacodynamic calculations, a dosing regimen of 500 mg b.i.d. may be ineffective in the treatment of soft-tissue infections caused by pathogens with a drug MIC higher than 0.125 mg/liter. PMID:17606673

  15. Pharmacokinetics of single- and multiple-dose oral clarithromycin in soft tissues determined by microdialysis.

    PubMed

    Traunmüller, Friederike; Zeitlinger, Markus; Zeleny, Petra; Müller, Markus; Joukhadar, Christian

    2007-09-01

    The antimicrobial spectrum of clarithromycin renders this antibiotic a frequently used option in the treatment of skin and soft-tissue infections. In most cases, these infections are caused by extracellularly proliferating microorganisms. Thus, clarithromycin concentrations achieved in the interstitial space are considered particularly important for clinical efficacy. In the present study, clarithromycin concentrations in plasma and interstitial-space fluid of subcutaneous adipose tissue and skeletal muscle of six healthy male volunteers were assessed by means of the microdialysis technique after oral single-dose administration of 250 mg and multiple doses of 500 mg of clarithromycin twice a day (b.i.d.). The ratios of the area under the concentration-time curve of free clarithromycin from 0 to 24 h calculated for a single dose of 250 mg (fAUC(0-24)) in interstitial-space fluid to the fAUC(0-24) in plasma were 0.29 +/- 0.17 and 0.42 +/- 0.18 for subcutis and skeletal muscle, respectively. For 500 mg of clarithromycin at the steady state (3 to 5 days of intake twice daily), the fAUC(0-24(b.i.d.)) ratios at the steady state were 0.39 +/- 0.04 and 0.41 +/- 0.19 for subcutis and skeletal muscle, respectively. The half-life was around 2 h after a single dose but increased to approximately 4 h in plasma and tissues after repetitive clarithromycin administration. Based on subsequently performed pharmacokinetic-pharmacodynamic calculations, a dosing regimen of 500 mg b.i.d. may be ineffective in the treatment of soft-tissue infections caused by pathogens with a drug MIC higher than 0.125 mg/liter. PMID:17606673

  16. Disposition of chloroquine in man after single intravenous and oral doses.

    PubMed

    Gustafsson, L L; Walker, O; Alván, G; Beermann, B; Estevez, F; Gleisner, L; Lindström, B; Sjöqvist, F

    1983-04-01

    1 Chloroquine was given in 300 mg single doses as an i.v. infusion, an oral solution and as tablets at intervals of at least 56 days to 11 healthy volunteers. Concentrations of chloroquine and its metabolite desethylchloroquine were measured in plasma, erythrocytes and urine using h.p.l.c. 2 Chloroquine was detectable in all plasma samples up to 23 days and occasionally up to 52 days after dosage. Urinary concentrations were monitored up to 119 days. The disposition pattern was multiexponential reflecting extensive tissue binding of the drug. 3 After i.v. dosing the volume of distribution ranged from 116 to 285 l/kg and the apparent terminal half-life from 146 to 333 h. Total plasma clearance +/- s.d. was 712 +/- 166 ml/min and renal clearance 412 +/- 139 ml/min. The mean estimated urinary recovery of chloroquine was 47%, 42% and 46% after i.v., oral solution and tablets indicating nearly complete bioavailability. The corresponding figures for the metabolite were 7%, 10% and 12%. 4 The disposition of chloroquine in erythrocytes was parallel to that in plasma. The concentrations in erythrocytes were consistently 2 to 5 times higher than in plasma. 5 Subjective side effects like difficulties with swallowing and accommodation, diplopia and fatigue occurred during intravenous infusion and were closely related to plasma concentrations. No effect was seen on the electrocardiogram, mean arterial blood pressure and pulse rate. No adverse reactions were observed after the oral doses. High frequency audiometry did not reveal any significant hearing impairment for the group as a whole.

  17. Pharmacokinetics of enrofloxacin after single dose oral and intravenous administration in the African penguin (Spheniscus demersus).

    PubMed

    Wack, Allison N; KuKanich, Butch; Bronson, Ellen; Denver, Mary

    2012-06-01

    The pharmacokinetics of a single dose of enrofloxacin administered orally, both pilled and in fish, and i.v. to African penguins (Spheniscus demersus) at 15 mg/kg were determined. Plasma concentrations of enrofloxacin and its metabolite ciprofloxacin were measured via high-pressure liquid chromatography with mass spectrometry. An i.v. administration of enrofloxacin resulted in an extrapolated mean plasma concentration of 7.86 microg/ml at time zero. Plasma volume of distribution for i.v. administration was 3.00 L/kg, with a mean elimination half-life of 13.67 hr and a mean total body clearance rate of 3.03 ml/min/kg. Oral administration of enrofloxacin achieved a mean maximum plasma concentration of4.38 microg/ml at 4.8 hr after administration when pilled, whereas mean maximum plasma concentration was 4.77 microg/ml at 1.59 hr after administration when given in fish. Mean terminal elimination half-life was 13.79 hr pilled and 11.93 hr when given in fish. Low concentrations of ciprofloxacin were detected after both oral and i.v. enrofloxacin administration. Enrofloxacin administered to African penguins at 15 mg/kg p.o.q. 24 hr, whether in fish or pilled, is expected to achieve the surrogate markers of efficacy for bacteria with a minimum inhibitory concentration of 0.5 microg/ml or less; however, clinical studies are needed to determine efficacy.

  18. Single dose oral indometacin for the treatment of acute postoperative pain

    PubMed Central

    Moore, R Andrew; Derry, Sheena; Mason, Lorna; McQuay, Henry J; Edwards, Jayne

    2014-01-01

    Background This is an updated version of the original Cochrane review published in Issue 4, 2004. Indometacin is a non-steroidal anti-inflammatory drug (NSAID) used most commonly for the treatment of inflammation and pain resulting from rheumatic disease (arthritis), and less commonly in postoperative pain management. When taken for chronic pain conditions, indometacin has been associated with a high incidence of adverse events. The benefits and harms of orally-administered indometacin for postoperative pain are not clear. Objectives To determine the efficacy of a single dose of oral indometacin compared with placebo in treating acute postoperative pain in adults, and to analyse information relating to adverse events. Search methods We searched the Cochrane CENTRAL Register of Controlled Trials in The Cochrane Library, MEDLINE, EMBASE and the Oxford Pain Relief Database for relevant studies in January 2002 and for the updated search in December 2007. Additional studies were sought from the reference lists of retrieved studies. Selection criteria Studies were included in the review if they were randomised, double blind, placebo-controlled clinical trials using a single oral dose of indometacin in adults with acute postoperative pain. Data collection and analysis Studies were assessed independently by two review authors. Pain relief or pain intensity data were extracted and converted into dichotomous information to give the number of participants with at least 50% pain relief over four to six hours. The relative benefit for at least 50% pain relief was calculated. Main results In the original review one study of 59 women with post-episiotomy pain met the inclusion criteria. The dose of indometacin assessed against placebo was 50 mg, and the results concluded that indometacin was not significantly better than placebo for relieving postoperative pain at four to six hours. There was insufficient information to conduct further efficacy analyses or assess adverse events

  19. Comparative metabolism studies of hexabromocyclododecane (HBCD) diastereomers in male rats following a single oral dose

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Male Sprague-Dawley rats were dosed orally with 3 mg/kg of one of three hexabromocyclododecane (HBCD) diastereomers. Each diastereomer was well absorbed (73-83%), and distributed preferentially to lipophilic tissues. Feces were the major route of excretion; cumulatively 42% of dose for alpha-HBCD,...

  20. Single dose oral naproxen and naproxen sodium for acute postoperative pain (Review)

    PubMed Central

    Mason, L; Edwards, JE; Moore, RA; McQuay, HJ

    2014-01-01

    Background Postoperative pain is often poorly managed. Treatment options include a range of drug therapies such as non-steroidal anti-inflammatory drugs (NSAIDs) of which naproxen is one. Naproxen is used to treat a variety of painful conditions including acute postoperative pain, and is often combined with sodium to improve its solubility for oral administration. Naproxen sodium 550 mg (equivalent to 500 mg of naproxen) is considered to be an effective dose for treating postoperative pain but to date no systematic review of the effectiveness of naproxen/naproxen sodium at different doses has been published. Objectives To assess the efficacy, safety and duration of action of a single oral dose of naproxen or naproxen sodium for acute postoperative pain in adults. Search strategy We searched The Cochrane Library, MEDLINE, EMBASE and the Oxford Pain Relief Database for relevant studies. Additional studies were identified from the reference list of retrieved reports. The most recent search was undertaken in July 2004. Selection criteria Included studies were randomised, double blind, placebo-controlled trials of a single dose of orally administered naproxen or naproxen sodium in adults with moderate to severe acute postoperative pain. Data collection and analysis Pain relief or pain intensity data were extracted and converted into dichotomous information to give the number of patients with at least 50% pain relief over four to six hours. Relative risk estimates (RR) and the number-needed-to-treat (NNT) for at least 50% pain relief were then calculated. Information was sought on the percentage of patients experiencing any adverse event, and the number-needed-to-harm was derived. Time to remedication was also estimated. Main results Ten trials (996 patients) met the inclusion criteria: nine assessed naproxen sodium; one combined the results from two small trials of naproxen alone. Included studies scored well for methodological quality. Meta-analysis of six trials (500

  1. Pharmacokinetics of enrofloxacin after single dose oral and intravenous administration in the African penguin (Spheniscus demersus).

    PubMed

    Wack, Allison N; KuKanich, Butch; Bronson, Ellen; Denver, Mary

    2012-06-01

    The pharmacokinetics of a single dose of enrofloxacin administered orally, both pilled and in fish, and i.v. to African penguins (Spheniscus demersus) at 15 mg/kg were determined. Plasma concentrations of enrofloxacin and its metabolite ciprofloxacin were measured via high-pressure liquid chromatography with mass spectrometry. An i.v. administration of enrofloxacin resulted in an extrapolated mean plasma concentration of 7.86 microg/ml at time zero. Plasma volume of distribution for i.v. administration was 3.00 L/kg, with a mean elimination half-life of 13.67 hr and a mean total body clearance rate of 3.03 ml/min/kg. Oral administration of enrofloxacin achieved a mean maximum plasma concentration of4.38 microg/ml at 4.8 hr after administration when pilled, whereas mean maximum plasma concentration was 4.77 microg/ml at 1.59 hr after administration when given in fish. Mean terminal elimination half-life was 13.79 hr pilled and 11.93 hr when given in fish. Low concentrations of ciprofloxacin were detected after both oral and i.v. enrofloxacin administration. Enrofloxacin administered to African penguins at 15 mg/kg p.o.q. 24 hr, whether in fish or pilled, is expected to achieve the surrogate markers of efficacy for bacteria with a minimum inhibitory concentration of 0.5 microg/ml or less; however, clinical studies are needed to determine efficacy. PMID:22779234

  2. The pharmacokinetics of methocarbamol and guaifenesin after single intravenous and multiple-dose oral administration of methocarbamol in the horse.

    PubMed

    Rumpler, M J; Colahan, P; Sams, R A

    2014-02-01

    A simple LC/MSMS method has been developed and fully validated to determine concentrations and characterize the concentration vs. time course of methocarbamol (MCBL) and guaifenesin (GGE) in plasma after a single intravenous dose and multiple oral dose administrations of MCBL to conditioned Thoroughbred horses. The plasma concentration-time profiles for MCBL after a single intravenous dose of 15 mg/kg of MCBL were best described by a three-compartment model. Mean extrapolated peak (C0 ) plasma concentrations were 23.2 (± 5.93) μg/mL. Terminal half-life, volume of distribution at steady-state, mean residence time, and systemic clearance were characterized by a median (range) of 2.96 (2.46-4.71) h, 1.05 (0.943-1.21) L/kg, 1.98 (1.45-2.51) h, and 8.99 (6.68-10.8) mL/min/kg, respectively. Oral dose of MCBL was characterized by a median (range) terminal half-life, mean transit time, mean absorption time, and apparent oral clearance of 2.89 (2.21-4.88) h, 2.67 (1.80-2.87) h, 0.410 (0.350-0.770) h, and 16.5 (13.0-20) mL/min/kg. Bioavailability of orally administered MCBL was characterized by a median (range) of 54.4 (43.2-72.8)%. Guaifenesin plasma concentrations were below the limit of detection in all samples collected after the single intravenous dose of MCBL whereas they were detected for up to 24 h after the last dose of the multiple-dose oral regimen. This difference may be attributed to first-pass metabolism of MCBL to GGE after oral administration and may provide a means of differentiating the two routes of administration. PMID:23859819

  3. Oral contraception does not alter single dose saquinavir pharmacokinetics in women

    PubMed Central

    Fröhlich, Margit; Burhenne, Jürgen; Martin-Facklam, Meret; Weiss, Johanna; von Wolff, Michael; Strowitzki, Thomas; Walter-Sack, Ingeborg; Haefeli, Walter E

    2004-01-01

    Aims Women experience more adverse drug reactions (ADR) to antiretroviral therapy than men. This may be attributed to higher plasma concentrations of protease inhibitors due to pharmacokinetic interactions with hormonal preparations. Thus, in the present study we aimed to investigate the influence of oral contraceptives (OC) on the pharmacokinetics of the protease inhibitor saquinavir. Methods Saquinavir was administered in a hard gelatin capsule formulation (Invirase®) to rule out confounding by pharmaceutical aids of the more frequently used soft gelatin capsule. After an overnight fast, eight healthy female participants ingested a single oral dose of 600 mg saquinavir immediately before and after the 19th dose of a combined, low dose OC (0.03 mg ethinylestradiol, 0.075 mg gestodene) in a prospective, fixed sequence study design. The first saquinavir application was scheduled on day 1, 2, or 3 of the individual menstrual cycle. Plasma concentrations of saquinavir and relative concentrations of its M2&M3-hydroxy metabolites were determined by LC/MS/MS for 48 h. Results Intake of OC resulted in a significant decrease in morning serum concentrations (before intake of OC, compared to day 19 of OC therapy) of 17β-estradiol by −23.4 pg ml−1 (57%, 95%CI: −76% to −37.4%); progesterone by −0.25 ng ml−1 (33%, 95%CI: −45.3% to −21.5%); follicle-stimulating hormone by −4.06 U l−1 (82%, 95%CI: −96.5% to −67.7%); and luteinizing hormone by −3.49 U l−1 (74%, 95%CI: −93 to −54.6%). Conversely, sexual hormone binding globulin serum concentrations increased by 83.6 nmol l−1 (205%, 95%CI: 32.2% to 377%). Pharmacokinetic parameters of saquinavir (AUC, Cmax, tmax, t1/2, CLR) were not affected by OC, nor was the relative metabolic ratio of saquinavir/M2&M3-hydroxy saquinavir. Furthermore, there was no association of serum hormone concentrations or MDR1-polymorphisms (C3435T and G2677T) with pharmacokinetic parameters of saquinavir. Conclusions There

  4. Single, Escalating Dose Pharmacokinetics, Safety and Food Effects of a New Oral Androgen Dimethandrolone Undecanoate in Man: A prototype oral male hormonal contraceptive

    PubMed Central

    Swerdloff, Ronald S.; Nya-Ngatchou, Jean Jacques; Liu, Peter Y.; Amory, John K.; Leung, Andrew; Hull, Laura; Blithe, Diana L.; Woo, Jason; Bremner, William J.; Wang, Christina

    2014-01-01

    The novel androgen, dimethandrolone (DMA) has both androgenic and progestational activities, properties that may maximize gonadotropin suppression. We assessed the pharmacokinetics of dimethandrolone undecanoate (DMAU), an orally bioavailable, longer-acting ester of DMA, for male contraceptive development. Our objective was to examine the safety and pharmacokinetics of single, escalating doses of DMAU (powder in capsule formulation) administered orally with or without food in healthy men. We conducted a randomized, double-blind Phase 1 study. For each dose of DMAU (25 to 800 mg), ten male volunteers received DMAU and two received placebo at two academic medical centers. DMAU was administered both fasting and after a high fat meal (200–800 mg doses). Serial serum samples were collected over 24h following each dose. DMAU was well tolerated without significant effects on vital signs, safety laboratory tests or electrocardiograms. When administered while fasting, serum DMA (active compound) was detectable in only 4/10 participants after the 800mg dose. When administered with a 50% fat meal, serum DMA was detectable in all participants given 200mg DMAU and showed a dose-incremental increase up to 800mg, with peak levels 4 to 8h after taking the dose. Serum gonadotropins and sex hormone concentrations were significantly suppressed 12h after DMAU administration with food at doses above 200mg. This first-in-man study demonstrated that a single, oral dose of DMAU up to 800 mg is safe. A high-fat meal markedly improved DMAU/DMA pharmacokinetics. PMID:24789057

  5. Concentrations of gemifloxacin at the target site in healthy volunteers after a single oral dose.

    PubMed

    Islinger, Florian; Bouw, Rene; Stahl, Mathias; Lackner, Edith; Zeleny, Petra; Brunner, Martin; Müller, Markus; Eichler, Hans Georg; Joukhadar, Christian

    2004-11-01

    Free gemifloxacin concentrations in the interstitial space fluid of skeletal muscle and subcutaneous adipose tissue were measured by means of in vivo microdialysis to characterize the ability of gemifloxacin to penetrate human soft tissues. Twelve healthy volunteers received a single oral dose of 320 mg of gemifloxacin. The mean areas under the concentration-time curves from 0 to 10 h (AUC(0-10)) were significantly higher for soft tissue than for unbound gemifloxacin in plasma (P < 0.05). The ratios of the mean AUC(0-10) for tissue to the AUC(0-10) for free gemifloxacin in plasma were 1.7 +/- 0.7 (mean +/- standard deviation) for skeletal muscle and 2.4 +/- 1.0 for adipose tissue. The AUC(0-24) ratios for free gemifloxacin in tissues to the MIC at which 90% of frequently isolated bacteria are inhibited were close to or higher than 100 h. Therefore, based on pharmacokinetic and pharmacodynamic calculations, we conclude that gemifloxacin might be a useful therapeutic option for the treatment of soft tissue infections. PMID:15504848

  6. Concentrations of Gemifloxacin at the Target Site in Healthy Volunteers after a Single Oral Dose

    PubMed Central

    Islinger, Florian; Bouw, Rene; Stahl, Mathias; Lackner, Edith; Zeleny, Petra; Brunner, Martin; Müller, Markus; Eichler, Hans Georg; Joukhadar, Christian

    2004-01-01

    Free gemifloxacin concentrations in the interstitial space fluid of skeletal muscle and subcutaneous adipose tissue were measured by means of in vivo microdialysis to characterize the ability of gemifloxacin to penetrate human soft tissues. Twelve healthy volunteers received a single oral dose of 320 mg of gemifloxacin. The mean areas under the concentration-time curves from 0 to 10 h (AUC0-10) were significantly higher for soft tissue than for unbound gemifloxacin in plasma (P < 0.05). The ratios of the mean AUC0-10 for tissue to the AUC0-10 for free gemifloxacin in plasma were 1.7 ± 0.7 (mean ± standard deviation) for skeletal muscle and 2.4 ± 1.0 for adipose tissue. The AUC0-24 ratios for free gemifloxacin in tissues to the MIC at which 90% of frequently isolated bacteria are inhibited were close to or higher than 100 h. Therefore, based on pharmacokinetic and pharmacodynamic calculations, we conclude that gemifloxacin might be a useful therapeutic option for the treatment of soft tissue infections. PMID:15504848

  7. A comparative study of oral single dose of metronidazole, tinidazole, secnidazole and ornidazole in bacterial vaginosis

    PubMed Central

    Thulkar, Jyoti; Kriplani, Alka; Agarwal, Nutan

    2012-01-01

    Objective: To compare the cure rates of oral single dose of metronidazole (2 g), tinidazole (2 g), secnidazole (2 g), and ornidazole (1.5 g) in cases of bacterial vaginosis. Materials and Methods: This was a prospective, comparative, randomized clinical trial on 344 Indian women (86 women in each group) who attended a gynecology outpatient department with complaint of abnormal vaginal discharge or who had abnormal vaginal discharge on Gynecological examination but they did not complaint of it. For diagnosis and cure rate of bacterial vaginosis, Amsel's criteria were used. Statistical analysis was done by Chi-square test of proportions. The cure rate was compared considering metronidazole cure rate as gold standard. Results: At 1 week, the cure rate of tinidazole and ornidazole was 100% and at 4 weeks, it was 97.7% for both drugs (P<0.001). Secnidazole had cure rate of 80.2% at 4 weeks (P=NS). Metronidazole showed a cure rate of 77.9% at 4 weeks, which is the lowest of all four drugs. Conclusion: Tinidazole and ornidazole have better cure rate as compared to metronidazole in cases of bacterial vaginosis. PMID:22529484

  8. Single dose oral paracetamol (acetaminophen) with codeine for postoperative pain in adults

    PubMed Central

    Toms, Laurence; Derry, Sheena; Moore, R Andrew; McQuay, Henry J

    2014-01-01

    Background This is an updated version of the Cochrane review published in Issue 4, 1998. Combining drugs from different classes with different modes of action may offer opportunity to optimise efficacy and tolerability, using lower doses of each drug to achieve the same degree of pain relief. Previously we concluded that addition of codeine to paracetamol provided additional pain relief, but at expense of additional adverse events. New studies have been published since. This review sought to evaluate efficacy and safety of paracetamol plus codeine using current data, and compare findings with other analgesics evaluated similarly. Objectives Assess efficacy of single dose oral paracetamol plus codeine in acute postoperative pain, increase in efficacy due to the codeine component, and associated adverse events. Search methods We searched CENTRAL, MEDLINE, EMBASE, the Oxford Pain Relief Database in October 2008 for this update. Selection criteria Randomised, double-blind, placebo-controlled trials of paracetamol plus codeine, compared with placebo or the same dose of paracetamol alone, for relief of acute postoperative pain in adults. Data collection and analysis Two authors assessed trial quality and extracted data. The area under the “pain relief versus time” curve was used to derive proportion of participants with paracetamol plus codeine and placebo or paracetamol alone experiencing least 50% pain relief over four-to-six hours, using validated equations. Number-needed-to-treat-to-benefit (NNT) was calculated using 95% confidence intervals (CIs). Proportion of participants using rescue analgesia over a specified time period, and time to use of rescue analgesia, were sought as additional measures of efficacy. Information on adverse events and withdrawals were collected. Main results Twenty-six studies, with 2295 participants, were included comparing paracetamol plus codeine with placebo. Significant dose response was seen for the outcome of at least 50% pain

  9. Pharmacokinetics, pharmacodynamics and food effect of LB30870, a novel direct thrombin inhibitor, after single oral doses in healthy men.

    PubMed

    Kim, John; Lee, Sung-Hack; Boyce, Malcolm; Warrington, Steve; Cho, Kwan Hyung; Yoon, Suk Kyoon; Park, Hee Dong; Kim, Aeri

    2015-01-01

    1. The safety, tolerability, pharmacokinetics, pharmacodynamics, and food effect of LB30870, a new selective thrombin inhibitor, were studied in 16 healthy men. 2. A double-blind, placebo-controlled single ascending dose study was done at oral doses of 5, 15, 30, 60, 120, and 240 mg under fasting conditions. An open, randomized, balanced cross-over food effect study was done at 60 mg dose. Plasma and urinary concentrations were measured up to 48 h post-dose. Coagulation and thrombin activity markers were measured at selected time points. 3. Cmax of LB30870 was at 1.3-3.0 h post-dose with a mean apparent terminal half-life (t1/2) of 2.8-4.1 h. AUC after doses above 15 mg appeared greater than dose-proportional. In fed state, AUC showed 80% reduction relative to fasting condition. 4. At doses 60 and 120 mg, peak activated partial thromboplastin time (aPTT) increased by 1.5- and 2-fold, respectively, from baseline. The aPTT and international normalized ratio (INR) were concentration-dependent, with less within-individual variability than ecarin clotting time (ECT), prothrombin time (PT), or thrombin time (TT). 5. Single oral doses of LB30870 up to 240 mg were well tolerated. The food effect must be overcome if LB30870 is to be used as an oral anti-coagulant. PMID:25673087

  10. Pharmacokinetics of a Single Dose of Oral and Subcutaneous Meloxicam in Caribbean Flamingos ( Phoenicopterus ruber ruber).

    PubMed

    Lindemann, Dana M; Carpenter, James W; KuKanich, Butch

    2016-03-01

    To determine the pharmacokinetics of meloxicam in Caribbean flamingos ( Phoenicopterus ruber ruber), a pilot study was performed first, followed by a complete pharmacokinetic study. Four healthy birds were divided into 2 groups and administered 1 mg/kg of either oral (n = 2) or subcutaneous (n = 2) meloxicam. Plasma meloxicam concentrations were determined with liquid chromatography-mass spectrometry. Based on the pilot study results, 12 healthy birds were assigned into 2 groups and administered either 3 mg/kg PO (n = 6) or 1.5 mg/kg SC (n = 6) of meloxicam. Blood samples were collected at baseline and at 9 time intervals per group after administration of meloxicam in all flamingos. Plasma concentrations after administration of 3 mg/kg PO meloxicam reached a mean maximum plasma concentration of 1.449 μg/mL at 2.35 hours with a terminal half-life of 1.832 hours. After administration of 1.5 mg/kg SC meloxicam, maximum plasma concentration was 4.059 μg/mL at 0.91 hour with a terminal half-life of 1.104 hours. The plasma profile from the main oral study (3 mg/kg PO) differed markedly from the pilot study (1 mg/kg PO), suggesting a delayed absorption with the higher dose and lack of dose proportionality. The different doses for subcutaneous administration resulted in a proportional change in plasma concentrations. Further studies are needed to evaluate the effects of the drug volume administered and fasting status when oral dosing is used. Future studies are also needed to investigate multiple-dose pharmacokinetics of meloxicam and to determine the therapeutic meloxicam plasma concentration in Caribbean flamingos.

  11. Human metabolism and excretion kinetics of aniline after a single oral dose.

    PubMed

    Modick, Hendrik; Weiss, Tobias; Dierkes, Georg; Koslitz, Stephan; Käfferlein, Heiko Udo; Brüning, Thomas; Koch, Holger Martin

    2016-06-01

    Aniline is an important source material in the chemical industry (e.g., rubber, pesticides, and pharmaceuticals). The general population is known to be ubiquitously exposed to aniline. Thus, assessment of aniline exposure is of both occupational and environmental relevance. Knowledge on human metabolism of aniline is scarce. We orally dosed four healthy male volunteers (two fast and two slow acetylators) with 5 mg isotope-labeled aniline, consecutively collected all urine samples over a period of 2 days, and investigated the renal excretion of aniline and its metabolites by LS-MS/MS and GC-MS. After enzymatic hydrolysis of glucuronide and sulfate conjugates, N-acetyl-4-aminophenol was the predominant urinary aniline metabolite representing 55.7-68.9 % of the oral dose, followed by the mercapturic acid conjugate of N-acetyl-4-aminophenol accounting for 2.5-6.1 %. Acetanilide and free aniline were found only in minor amounts accounting for 0.14-0.36 % of the dose. Overall, these four biomarkers excreted in urine over 48 h post-dose represented 62.4-72.1 % of the oral aniline dose. Elimination half-times were 3.4-4.3 h for N-acetyl-4-aminophenol, 4.1-5.5 h for the mercapturic acid conjugate, and 1.3-1.6 and 0.6-1.2 h for acetanilide and free aniline, respectively. Urinary maximum concentrations of N-acetyl-4-aminophenol were reached after about 4 h and maximum concentrations of the mercapturic acid conjugate after about 6 h, whereas concentrations of acetanilide and free aniline peaked after about 1 h. The present study is one of the first to provide reliable urinary excretion factors for aniline and its metabolites in humans after oral dosage, including data on the predominant urinary metabolite N-acetyl-4-aminophenol, also known as an analgesic under the name paracetamol/acetaminophen.

  12. Human metabolism and excretion kinetics of aniline after a single oral dose.

    PubMed

    Modick, Hendrik; Weiss, Tobias; Dierkes, Georg; Koslitz, Stephan; Käfferlein, Heiko Udo; Brüning, Thomas; Koch, Holger Martin

    2016-06-01

    Aniline is an important source material in the chemical industry (e.g., rubber, pesticides, and pharmaceuticals). The general population is known to be ubiquitously exposed to aniline. Thus, assessment of aniline exposure is of both occupational and environmental relevance. Knowledge on human metabolism of aniline is scarce. We orally dosed four healthy male volunteers (two fast and two slow acetylators) with 5 mg isotope-labeled aniline, consecutively collected all urine samples over a period of 2 days, and investigated the renal excretion of aniline and its metabolites by LS-MS/MS and GC-MS. After enzymatic hydrolysis of glucuronide and sulfate conjugates, N-acetyl-4-aminophenol was the predominant urinary aniline metabolite representing 55.7-68.9 % of the oral dose, followed by the mercapturic acid conjugate of N-acetyl-4-aminophenol accounting for 2.5-6.1 %. Acetanilide and free aniline were found only in minor amounts accounting for 0.14-0.36 % of the dose. Overall, these four biomarkers excreted in urine over 48 h post-dose represented 62.4-72.1 % of the oral aniline dose. Elimination half-times were 3.4-4.3 h for N-acetyl-4-aminophenol, 4.1-5.5 h for the mercapturic acid conjugate, and 1.3-1.6 and 0.6-1.2 h for acetanilide and free aniline, respectively. Urinary maximum concentrations of N-acetyl-4-aminophenol were reached after about 4 h and maximum concentrations of the mercapturic acid conjugate after about 6 h, whereas concentrations of acetanilide and free aniline peaked after about 1 h. The present study is one of the first to provide reliable urinary excretion factors for aniline and its metabolites in humans after oral dosage, including data on the predominant urinary metabolite N-acetyl-4-aminophenol, also known as an analgesic under the name paracetamol/acetaminophen. PMID:26233686

  13. Comparative effects of single intraperitoneal or oral doses of sodium arsenate or arsenic trioxide during in utero development.

    PubMed

    Stump, D G; Holson, J F; Fleeman, T L; Nemec, M D; Farr, C H

    1999-11-01

    Numerous studies have suggested that single-day intraperitoneal (IP) injection of inorganic arsenic results in failure of neural tube closure and other malformations in rats, hamsters, and mice. Most of these studies involved treatment of limited numbers of animals with maternally toxic doses of arsenic (generally As(V)), without defining a dose-response relationship. In the present Good Laboratory Practice-compliant study, sodium arsenate (As(V)) was administered IP and arsenic trioxide (As(III)) was administered either IP or orally (by gavage) on gestational day 9 to groups of 25 mated Crl:CD(R)(SD)BR rats. Only at dose levels that caused severe maternal toxicity, including lethality, did IP injection of arsenic trioxide produce neural tube and ocular defects; oral administration of higher doses of arsenic trioxide caused some maternal deaths but no treatment-related fetal malformations. In contrast, IP injection of similar amounts of sodium arsenate (based on the molar amount of arsenic) caused mild maternal toxicity but a large increase in malformations, including neural tube, eye, and jaw defects. In summary, neural tube and craniofacial defects were observed after IP injection of both As(V) and As(III); however, no increase in malformations was seen following oral administration of As(III), even at maternally lethal doses. These results demonstrate that the frequently cited association between prenatal exposure to inorganic arsenic and malformations in laboratory animals is dependent on a route of administration that is not appropriate for human risk assessment.

  14. Single Oral Dose Pharmacokinetics of Decursin and Decursinol Angelate in Healthy Adult Men and Women

    PubMed Central

    Zhang, Jinhui; Li, Li; Hale, Thomas W.; Chee, Wayne; Xing, Chengguo; Jiang, Cheng; Lü, Junxuan

    2015-01-01

    The ethanol extract of Angelica gigas Nakai (AGN) root has promising anti-cancer and other bioactivities in rodent models. It is currently believed that the pyranocoumarin isomers decursin (D) and decursinol angelate (DA) contribute to these activities. We and others have documented that D and DA were rapidly converted to decursinol (DOH) in rodents. However, our in vitro metabolism studies suggested that D and DA might be metabolized differently in humans. To test this hypothesis and address a key question for human translatability of animal model studies of D and DA or AGN extract, we conducted a single oral dose human pharmacokinetic study of D and DA delivered through an AGN-based dietary supplement Cogni.Q (purchased from Quality of Life Labs, Purchase, NY) in twenty healthy subjects, i.e., 10 men and 10 women, each consuming 119 mg D and 77 mg DA from 4 vegicaps. Analyses of plasma samples using UHPLC-MS/MS showed mean time to peak concentration (Tmax) of 2.1, 2.4 and 3.3 h and mean peak concentration (Cmax) of 5.3, 48.1 and 2,480 nmol/L for D, DA and DOH, respectively. The terminal elimination half-life (t1/2) for D and DA was similar (17.4 and 19.3 h) and each was much longer than that of DOH (7.4 h). The mean area under the curve (AUC0-48h) for D, DA and DOH was estimated as 37, 335 and 27,579 h∙nmol/L, respectively. Gender-wise, men absorbed the parent compounds faster and took shorter time to reach DOH peak concentration. The human data supported an extensive conversion of D and DA to DOH, even though they metabolized DA slightly slower than rodents. Therefore, the data generated in rodent models concerning anti-cancer efficacy, safety, tissue distribution and pharmacodynamic biomarkers will likely be relevant for human translation. Trial Registration ClinicalTrials.gov NCT02114957 PMID:25695490

  15. Immunization with Single Oral Dose of Alginate-Encapsulated BCG Elicits Effective and Long-Lasting Mucosal Immune Responses.

    PubMed

    Hosseini, M; Dobakhti, F; Pakzad, S R; Ajdary, S

    2015-12-01

    Effective vaccination against pathogens, which enter the body through mucosal surfaces, requires the induction of both mucosal and systemic immune responses. Here, mucosal as well as systemic immune responses in the lung and spleen of BALB/c mice which were orally vaccinated with a single dose of alginate-encapsulated bacille Calmette-Guerin (BCG) were evaluated. Twenty weeks after immunization, the vaccinated mice were challenged intranasally with BCG. Twelve weeks after immunization and 5 weeks after challenge, the immune responses were evaluated. Moreover, immune responses were compared with those of mice that were vaccinated with free BCG by subcutaneous (sc) and oral routes. Twelve weeks after the immunization, serum IgG level was higher in the sc-immunized mice, while serum IgA level was higher in the orally immunized mice with encapsulated BCG. Significant productions of both IgG and IgA were only detected in lungs of mice orally immunized with encapsulated BCG. Proliferative and delayed-type hypersensitivity responses and IFN-γ production were significantly higher in mice immunized orally with encapsulated BCG, compared to mice immunized orally with free BCG. After challenge, the levels of IFN-γ were comparable between sc-immunized mice with free BCG and orally immunized with encapsulated BCG; however, significantly less IL-4 was detected in mice which had received encapsulated BCG via oral route. Moreover, significant control of the bacilli growth in the lung of the immunized mice after intranasal challenge with BCG was documented in mice vaccinated with encapsulated BCG. These results suggest that oral immunization with alginate-encapsulated BCG is an effective mean of inducing mucosal and systemic specific immune responses.

  16. Toxico-kinetics, recovery, and metabolism of napropamide in goats following a single high-dose oral administration.

    PubMed

    Pahari, A K; Majumdar, S; Mandal, T K; Chakraborty, A K; Bhattacharyya, A; Chowdhury, A

    2001-04-01

    Toxicokinetic behavior, recovery and metabolism of napropamide (a pre-emergent herbicide) and its effect on Cytochrome P(450) of liver microsomal pellet were studied following a single high-dose oral administration of 2.5 g kg(-1) and continuous (7 days) oral administration of 500 mg kg(-1) in black Bengal goat. Napropamide was detected in blood at 15 min and the maximum quantity was recovered at 3 h after administration. The absorption rate constant (Ka) value was low indicating poor absorption from the gastrointestinal tract. High elimination half-life (t(1/2) beta) and low body clearance (Cl(B)) values coupled with higher transfer of compound from tissue to central compartment (K(21)) suggest that napropamide persisted in the blood for a long time, i.e., after 72 h of oral administration. The recovery percentage of napropamide, including metabolites, from goats varied from 75.94 to 80.08 and excretion of the parent compound through feces varied from 18.86 to 21.59%, indicating that a major portion of the orally administered napropamide was absorbed from the gastrointestinal tract of goat. Napropamide significantly increased the Cytochrome P(450) content of liver microsomal pellet. The recovery of metabolites from feces, urine, and tissues ranged from 4.2--6.2, 40.81--49.42, and 2.7--11.6%, respectively, during a 4--7 day period. The material balance of napropamide (including metabolites) following a single high-dose oral administration at 2.5 g kg(-1) during 4--7 days after dosing was found to be in the range of 75--80%. PMID:11308331

  17. Albendazole and its metabolites in the breast milk of lactating women following a single oral dose of albendazole

    PubMed Central

    Abdel-tawab, Ahmed M; Bradley, Mark; Ghazaly, Essam A; Horton, John; El-Setouhy, Maged

    2009-01-01

    AIMS Albendazole (ABZ) is used in several anthelminthic drug programmws. ABZ side-effects are generally mild, but ABZ-induced pancytopenia may be serious. In filariasis programmes, it may be necessary to administer ABZ to breastfeeding women. Few data are available on safety of ABZ for breastfed infants. In addition, the pharmacokinetics of ABZ and its metabolites in human milk is insufficiently investigated. The aim was to study pharmacokinetics of ABZ and its metabolites [ABZ sulphoxide (ABSX) and ABZ sulphone] in the breast milk lactating women after one single oral dose of ABZ. METHODS Thirty-three lactating women (age 18–40 years) participated in the study. They received a single oral 400-mg dose of ABZ. Five milk samples were taken at 0, 6, 12, 24 and 36 h. One serum sample was taken after 6 h. Samples were analysed using high-performance liquid chromatography and pharmacokinetic analysis was performed. RESULTS ABZ was detectable in milk samples 6 h after the oral dose. The mean concentration of serum ABZ was 63.7 ± 11.9 ng ml−1. The pharmacokinetic parameters for ABSX were calculated as follows: 351.9 ± 32.4 ng ml−1, 6.9 ± 0.5 h, 12.4 ± 2.2 h and 5190.3 ± 482.8 ng*h ml−1 for Cmax, Tmax, t½ and AUC0–36, respectively. The milk-to-serum ratios (range) for ABZ and ABSX were 0.9 (0.2–6.5) and 0.6 (0.1–1.5), respectively. CONCLUSIONS After an oral dose of 400 mg, ABZ and ABSX attain low concentrations in breast milk that are unlikely to be considered harmful for the breastfed infant. PMID:19916998

  18. Comparative Metabolism Studies of Hexabromocyclododecane (HBCD) Diastereomers in Male Rats Following a Single Oral Dose.

    PubMed

    Hakk, Heldur

    2016-01-01

    Male Sprague-Dawley rats were dosed orally with 3 mg/kg of one of three hexabromocyclododecane (HBCD) diastereomers. Each diastereomer was well absorbed (73-83%), and distributed preferentially to lipophilic tissues. Feces were the major route of excretion; cumulatively accounting for 42% of dose for α-HBCD, 59% for ß-HBCD, and 53% for γ-HBCD. Urine was also an important route of HBCD excretion, accounting for 13% of dose for α-HBCD, 30% for ß-HBCD, and 21% for γ-HBCD. Total metabolism of HBCD diastereomers followed the rank order ß > γ > α, and was >65% of that administered. The metabolites formed were distinct in male rats: α-HBCD did not debrominate or stereoisomerize, but formed two hydroxylated metabolites; ß- and γ-HBCD were both extensively metabolized via pathways of stereoisomerization, oxidation, dehydrogenation, reductive debromination, and ring opening. ß-HBCD was biotransformed to two mercapturic acid pathway metabolites. The metabolites of ß- and γ-HBCD were largely distinct, and could possibly be used as markers of exposure. These isomer-specific data suggest that α-HBCD would be the most dominant HBCD diastereomer in biological tissues because it was metabolized to the lowest degree and also accumulated from the stereoisomerization of the β- and γ- diastereomers. PMID:26629593

  19. Voriconazole Disposition After Single and Multiple, Oral Doses in Healthy, Adult Red-tailed Hawks ( Buteo jamaicensis ).

    PubMed

    Gentry, Jordan; Montgerard, Christy; Crandall, Elizabeth; Cruz-Espindola, Crisanta; Boothe, Dawn; Bellah, Jamie

    2014-09-01

    Voriconazole is effective for treatment of aspergillosis, a common disease in captive red-tailed hawks ( Buteo jamaicensis ). To determine the disposition and safety of voriconazole after single and multiple, oral doses, 12 adult red-tailed hawks were studied in 2 phases. In phase 1, each bird received a single dose of voriconazole solution (10 mg/kg) by gavage. Blood samples were collected at 0, 0.5, 1, 3, 6, 9, 12, 16, 24, and 36 hours after treatment. In phase 2, each of 8 birds received voriconazole oral solution at 10 mg/kg PO q12h for 14 days. Plasma samples were collected on days 0, 5, and 10 and after the final dose and were processed as in phase 1. Plasma samples were submitted for analysis of voriconazole levels by high-performance liquid chromatography and ultraviolet spectrophotometry and for measurement of selected plasma biochemical parameters. After single dosing, voriconazole concentrations reached a (mean ± SD) peak (Cmax) of 4.7 ± 1.3 μg/mL at 2.0 ± 1.2 hours. The disappearance half-life (t1/2) was 2.8 ± 0.7 hours, and the mean residence time (MRT) was 4.6 ± 0.9 hours. After the last dose at 14 days, the mean Cmax of voriconazole was 4.5 ± 2.7 μg/mL at 2.4 ± 1.1 hours. The t1/2 was 2.1 ± 0.8 hours, and the MRT was 3.5 ± 1.1 hours. Although concentrations of several plasma biochemical parameters were significantly different at study end compared with prestudy concentrations, only plasma creatine kinase activity was outside the reference range. No adverse reactions were observed in any of the birds. After both single and multiple dosing at 10 mg/kg, voriconazole concentrations exceeded the minimum inhibitory concentration to inhibit 90% (MIC90) of Aspergillus species (1 μg/mL) by at least fourfold and remained above the MIC90 for 8.8 ± 1.1 hours after single dosing versus 6.5 ± 1.5 hours after multiple dosing (P = .003). This difference suggests that more frequent dosing (eg, up to q8h) may be necessary to maintain target

  20. A single-dose of oral nattokinase potentiates thrombolysis and anti-coagulation profiles

    PubMed Central

    Kurosawa, Yuko; Nirengi, Shinsuke; Homma, Toshiyuki; Esaki, Kazuki; Ohta, Mitsuhiro; Clark, Joseph F.; Hamaoka, Takafumi

    2015-01-01

    Our aim was to determine the quantitative effects of a single-dose of Nattokinase (NK) administration on coagulation/fibrinolysis parameters comprehensively in healthy male subjects. A double-blind, placebo-controlled cross-over NK intervention study was carried out in 12 healthy young males. Following the baseline blood draw, each subject was randomized to receive either a single-dose of 2,000 FU NK (NSK-SD, Japan Bio Science Laboratory Co., Ltd) or placebo with subsequent cross-over of the groups. Subjects donated blood samples at 2, 4, 6 and 8 hours following administration for analysis of coagulation/fibrinolysis parameters. As a result, D-dimer concentrations at 6, and 8 hours, and blood fibrin/fibrinogen degradation products at 4 hours after NK administration elevated significantly (p < 0.05, respectively). Factor VIII activity declined at 4 and 6 hours (p < 0.05, respectively), blood antithrombin concentration was higher at 2 and 4 hours (p < 0.05, respectively), and the activated partial thromboplastin time prolonged significantly at 2 and 4 hours following NK administration (p < 0.05 and p < 0.01, respectively). All the changes, however, were within the normal range. In conclusion, thus, a single-dose of NK administration appears enhancing fibrinolysis and anti-coagulation via several different pathways simultaneously. PMID:26109079

  1. A single-dose of oral nattokinase potentiates thrombolysis and anti-coagulation profiles.

    PubMed

    Kurosawa, Yuko; Nirengi, Shinsuke; Homma, Toshiyuki; Esaki, Kazuki; Ohta, Mitsuhiro; Clark, Joseph F; Hamaoka, Takafumi

    2015-06-25

    Our aim was to determine the quantitative effects of a single-dose of Nattokinase (NK) administration on coagulation/fibrinolysis parameters comprehensively in healthy male subjects. A double-blind, placebo-controlled cross-over NK intervention study was carried out in 12 healthy young males. Following the baseline blood draw, each subject was randomized to receive either a single-dose of 2,000 FU NK (NSK-SD, Japan Bio Science Laboratory Co., Ltd) or placebo with subsequent cross-over of the groups. Subjects donated blood samples at 2, 4, 6 and 8 hours following administration for analysis of coagulation/fibrinolysis parameters. As a result, D-dimer concentrations at 6, and 8 hours, and blood fibrin/fibrinogen degradation products at 4 hours after NK administration elevated significantly (p < 0.05, respectively). Factor VIII activity declined at 4 and 6 hours (p < 0.05, respectively), blood antithrombin concentration was higher at 2 and 4 hours (p < 0.05, respectively), and the activated partial thromboplastin time prolonged significantly at 2 and 4 hours following NK administration (p < 0.05 and p < 0.01, respectively). All the changes, however, were within the normal range. In conclusion, thus, a single-dose of NK administration appears enhancing fibrinolysis and anti-coagulation via several different pathways simultaneously.

  2. Pharmacokinetics and systemic endocrine effects of the phyto-oestrogen 8-prenylnaringenin after single oral doses to postmenopausal women

    PubMed Central

    Rad, M; Hümpel, M; Schaefer, O; Schoemaker, R C; Schleuning, W-D; Cohen, A F; Burggraaf, J

    2006-01-01

    Aims Pre-clinical data suggest that the racemic phyto-oestrogen 8-prenylnaringenin (8-PN) may have beneficial effects in postmenopausal women and may become an alternative to classical hormone replacement therapy (HRT) treatment regimes. The aim of this study was to investigate the pharmacokinetics, endocrine effects and tolerability of chemically synthesized 8-PN in postmenopausal women. Methods The study was performed using a randomized, double-blind, placebo-controlled, dose-escalation design with three groups of eight healthy postmenopausal women. In each group six subjects received 8-PN and two subjects placebo. 8-PN was given orally in doses of 50, 250 or 750 mg. Drug concentrations in serum, urine and faeces were measured up to 48 h and follicle-stimulating hormone/luteinizing hormone (LH) concentrations up to 24 h. Results All treatments were well tolerated and associated with a low incidence of (drug unrelated) adverse events. Serum concentrations of free 8-PN showed rapid drug absorption and secondary peaks suggestive of marked enterohepatic recirculation. Independent of the treatment group, approximately 30% of the dose was recovered in excreta as free compound or conjugates over the 48-h observation period. The first Cmax and AUC0–48 h showed dose linearity with ratios of 1 : 4.5 : 13.6 (Cmax) and 1 : 5.2 : 17.1 (AUC). The 750- mg dose decreased LH concentrations by 16.7% (95% confidence interval 0.5, 30.2). Conclusion Single oral doses of up to 750 mg 8-PN were well tolerated by postmenopausal women. The pharmacokinetic profile of 8-PN was characterized by rapid and probably complete enteral absorption, high metabolic stability, pronounced enterohepatic recirculation and tight dose linearity. The decrease in LH serum concentrations found after the highest dose demonstrates the ability of 8-PN to exert systemic endocrine effects in postmenopausal women. PMID:16934044

  3. Comparison of single-dose oral grepafloxacin with cefixime for treatment of uncomplicated gonorrhea in men. The STD Study Group.

    PubMed Central

    Hook, E W; McCormack, W M; Martin, D; Jones, R B; Bean, K; Maroli, A N

    1997-01-01

    In a randomized open study, 351 male patients with uncomplicated gonorrhea were given single oral doses of grepafloxacin (400 mg) or cefixime (400 mg). In the 299 microbiologically evaluable patients, urethral infections were cured in 99% (147 of 149) of those receiving grepafloxacin and 97% (145 of 150) of those given cefixime. Eradication rates for both regimens were 100% in the 16% (47 of 299) of participants who were infected with penicillin-resistant Neisseria gonorrhoeae and 97% in the 21% (62 of 299) of participants infected with tetracycline-resistant strains. Grepafloxacin is a well-tolerated alternative to cefixime for treatment of uncomplicated gonorrhea in males. PMID:9257777

  4. Pharmacokinetics of CGP 6140 (amocarzine) after oral administration of single 100-1600 mg doses to patients with onchocerciasis.

    PubMed Central

    Lecaillon, J B; Dubois, J P; Awadzi, K; Poltera, A A; Ginger, C D

    1990-01-01

    The concentrations of CGP 6140 [4-nitro-4'-(N-methyl-piperazinylthiocarbonylamido)-diphenylamine] and of its N-oxide metabolite, CGP 13,231, were measured in plasma and urine after single oral dose of 100-1600 mg of CGP 6140 to 41 fasted Ghanaian patients with Onchocerca volvulus infections. The absorption of CGP 6140 was rapid and its terminal elimination half-life was about 3 h. The plasma concentrations of CGP 6140 were essentially proportional to the dose. A greater variability in plasma concentrations was apparent after the 800 and 1600 mg doses indicating a poor bioavailability of the drug administered in fasting conditions to several patients. In plasma, the concentrations of CGP 13,231 were similar to those of CGP 6140. The amount of CGP 13,231 excreted in urine was 25-40% of the dose of CGP 6140 whereas only 1.5% was excreted as unchanged drug. If a single dose of drug is used for the treatment, the plasma concentration would be maintained for 3-4 h at a high level. At 8 h, the concentration falls to about 10% of the Cmax. If sustained plasma concentrations of the drug are needed for efficacy, twice daily administration would maintain the minimum concentration at about 10% of the Cmax. PMID:2291876

  5. Long-term follow-up analysis of zolpidem in fingernails after a single oral dose.

    PubMed

    Hang, Chen; Ping, Xiang; Min, Shen

    2013-09-01

    The determination of xenobiotics in keratinized matrices, such as nails and hair, has received considerable attention because of the relatively long detection window for compounds. The distribution of xenobiotics in fingernails, unlike hair, was equivocal. The main aim of this study was to use follow-up surveys to measure zolpidem profiles in nails after subjects consumed a single dose of the drug. In addition, the zolpidem concentrations in nails were compared with data for different biosamples, such as hair and blood from previous work. With these preconditions, a high-performance liquid chromatography-tandem mass spectrometry method was developed and validated for the determination of zolpidem in nails. Nails underwent alkaline hydrolysis and were extracted with diethyl ether. A Capcell Pak C18 MGII column was used to separate the target compound, and an API 4000 Qtrap mass spectrometer was used as a detector. The results for nail samples from seven subjects who had taken a single 10 mg zolpidem dose were significant: two relatively high zolpidem concentrations were observed in the long-term follow-up analysis of nails. The zolpidem concentration was less than 1.74 pg/mg and less than 3.29 pg/mg in fingernails and toenails, respectively. The subsequent peak concentration of zolpidem was observed between 10 and 15 weeks after each subject took a single dose of the drug. This result suggested that the germinal matrix area was a primary in vivo pathway for zolpidem secretion into the nail. The analysis of biosamples, such as nails, may be a useful adjunct to conventional methods of drug testing and hair analysis. Further research is needed concerning the contamination risk in analysis of nail biosamples.

  6. Single dose pharmacokinetics of atorvastatin oral formulations using a simple HPLC-UV method.

    PubMed

    Sohail, Muhammad; Ahmad, Mahmood; Minhas, Muhammad Usman

    2016-07-01

    The study was aimed to assess pharmacokinetics of atorvastatin (40 mg) in healthy fasted human subjects by a simple and inexpensive high performance liquid chromatography. Experimental design of the study was a randomized, two way, two periods, crossover study (single dose in fasted conditions). Eighteen (18) healthy male volunteers were enrolled according to FDA guidelines. The plasma samples were assayed using an isocratic High Performance Liquid Chromatography (HPLC) system of Agilent technologies USA consisted of an isocratic pump with column of Thermo Electron Corporation USA (ODS hypersil C(18) 4.6 mm x 250 mm), a UV-visible detector set at λ(max) 237 nm. Maximum plasma concentrations (C(max)) of atorvastatin (Mean ± SEM) for the reference product (A) found to be 13.739±0.210ng/ml & 13.374±0.145ng/ml for test product (B). T(max) values (Mean±SEM) of atorvastatin were 1.222 ±0.060 hours and 1.167±0.057 hours for reference and test products, respectively. The values of AUC(0-oo) (Mean ± SEM) for the reference (A) and test product (B) were 73.955 ± 1.715ng.h/ml and 77.773 ± 1.858ng. h/ml, respectively. Other pharmacokinetic parameters of both products were also determined. A statistical non-significant difference between pharmacokinetic parameters has been found and both brands of atorvastatin showed the same rate and extent of absorption in healthy fasted human volunteers after single dose. A simple and cost effective HPLC method was developed and applied. PMID:27393428

  7. Sensitive and specific radioimmunoassay for fialuridine: initial assessment of pharmacokinetics after single oral doses to healthy volunteers.

    PubMed Central

    Bowsher, R R; Compton, J A; Kirkwood, J A; Place, G D; Jones, C D; Mabry, T E; Hyslop, D L; Hatcher, B L; DeSante, K A

    1994-01-01

    Fialuridine (FIAU) is a halogen-substituted analog of thymidine that was undergoing clinical investigation as a drug for the treatment of chronic hepatitis B viral infection. However, clinical trials of FIAU were terminated after adverse events occurred following chronic oral administration. Prior to the termination of clinical trials, a sensitive assay was needed for the measurement of FIAU because of the anticipated low dose administered to patients. We therefore undertook the development of a radioimmunoassay (RIA). A specific antiserum was raised in rabbits following immunization with a 5'-O-hemisuccinate analog of FIAU coupled to keyhole limpet hemocyanin. Radiolabeled FIAU was synthesized by a destannylation procedure by using sodium [125I]iodide. We developed a competitive-binding procedure and used precipitation with polyethylene glycol as the method for separating the bound and free forms of FIAU. The RIA is sensitive (0.2 ng/ml), specific (negligible interference from known metabolites and endogenous nucleosides), and reproducible (interassay coefficients of variation range from 5 to 19.7% for serum controls). We used the RIA to assess the pharmacokinetics of FIAU in healthy adult volunteers following administration of a single 5-mg oral dose. The sensitivity of the RIA permitted the detection of a prolonged elimination phase for FIAU in healthy volunteers and dogs, with mean elimination half-lives of 29.3 and 35.3 h, respectively. We conclude the RIA is a valid method for the quantification of FIAU in biological fluids. PMID:7811032

  8. Population pharmacokinetics of artesunate and dihydroartemisinin following single- and multiple-dosing of oral artesunate in healthy subjects

    PubMed Central

    2009-01-01

    Background The population pharmacokinetics of artesunate (AS) and its active metabolite dihydroartemisinin (DHA) were studied in healthy subjects receiving single- or multiple-dosing of AS orally either in combination with pyronaridine (PYR) or as a monotherapy with or without food. Methods Data from 118 concentration-time profiles arising from 91 healthy Korean subjects were pooled from four Phase I clinical studies. Subjects received 2-5 mg/kg of single- and multiple-dosing of oral AS either in combination with PYR or as a monotherapy with or without food. Plasma AS and DHA were measured simultaneously using a validated liquid chromatography- mass spectrometric method with a lower limit of quantification of 1 ng/mL for both AS and DHA. Nonlinear mixed-effect modelling was used to obtain the pharmacokinetic and variability (inter-individual and residual variability) parameter estimates. Results A novel parent-metabolite pharmacokinetic model consisting of a dosing compartment, a central compartment for AS, a central compartment and a peripheral compartment for DHA was developed. AS and DHA data were modelled simultaneously assuming stoichiometric conversion to DHA. AS was rapidly absorbed with a population estimate of absorption rate constant (Ka) of 3.85 h-1. The population estimates of apparent clearance (CL/F) and volume of distribution (V2/F) for AS were 1190 L/h with 36.2% inter-individual variability (IIV) and 1210 L with 57.4% IIV, respectively. For DHA, the population estimates of apparent clearance (CLM/F) and central volume of distribution (V3/F) were 93.7 L/h with 28% IIV and 97.1 L with 30% IIV, respectively. The population estimates of apparent inter-compartmental clearance (Q/F) and peripheral volume of distribution (V4/F) for DHA were 5.74 L/h and 18.5 L, respectively. Intake of high-fat and high-caloric meal prior to the drug administration resulted in 84% reduction in Ka. Body weight impacted CLM/F, such that a unit change in weight resulted in 1

  9. Effects of a single, high oral dose of 25-hydroxycholecalciferol on the mineral metabolism markers in hemodialysis patients.

    PubMed

    Merino, Jose Luis; Teruel, Jose Luis; Fernández-Lucas, Milagros; Villafruela, Juan José; Bueno, Blanca; Gomis, Antonio; Paraíso, Vicente; Quereda, Carlos

    2015-06-01

    Vitamin D deficiency is common in dialysis patients with chronic kidney disease. Low levels have been associated with increased cardiovascular risk and mortality. We evaluated the administration of a high, single oral dose of 25-OH cholecalciferol (3 mg of Hidroferol, 180 000 IU) in patients on chronic hemodialysis. The 94 chronic hemodialysis patients with vitamin D deficiency 25 (OH)D <30 ng/mL included in the study were randomized into two groups. Follow-up time was 16 weeks. Neither the usual treatment for controlling Ca/P levels nor the dialysis bath (calcium of 2.5 mEq/L) were modified. Of the 86 patients who finished the study, 42 were in the treated group and 44 in the control group. An increase in 25(OH)D levels was observed in the treated group that persisted after 16 weeks and was associated with a significant decrease in parathyroid hormone (PTH) levels during the 8 weeks post-treatment. Baseline 1,25(OH)2 D levels of the treated group increased two weeks after treatment (5.9 vs. 21.9 pg/mL, P<0.001) but gradually reduced to 8.4 at week 16. The administration of a single 3 mg dose of 25-OH cholecalciferol seems safe in patients on hemodialysis and maintains sufficient levels of 25(OH)D with a decrease in PTH for 3 months.

  10. Single- and multiple-dose pharmacokinetics of marbofloxacin after oral administration to rabbits.

    PubMed

    Carpenter, James W; Pollock, Christal G; Koch, David E; Hunter, Robert P

    2009-04-01

    OBJECTIVE-To determine the pharmacokinetics of marbofloxacin after oral administration every 24 hours to rabbits during a 10-day period. ANIMALS-8 healthy 9-month-old female New Zealand White rabbits. PROCEDURES-Marbofloxacin (5 mg/kg) was administered orally every 24 hours to 8 rabbits for 10 days. The first day of administration was designated as day 1. Blood samples were obtained at 0, 0.17, 0.33, 0.5, 0.75, 1, 1.5, 2, 3, 4, 5, 6, 8, 12, and 24 hours on days 1 and 10 of marbofloxacin administration. Plasma marbofloxacin concentrations were quantitated by use of a validated liquid chromatography-mass spectrometry assay. Pharmacokinetic analysis of marbofloxacin was analyzed via noncompartmental methods. RESULTS-After oral administration, mean +/- SD area under the curve was 10.50 +/- 2.00 microg.h/mL and 10.90 +/- 2.45 microg.h/mL, maximum plasma concentration was 1.73 +/- 0.35 microg/mL and 2.56 +/- 0.71 microg/mL, and harmonic mean terminal half-life was 8.0 hours and 3.9 hours for days 0 and 10, respectively. CONCLUSIONS AND CLINICAL RELEVANCE-Marbofloxacin administered orally every 24 hours for 10 days appeared to be absorbed well and tolerated by rabbits. Administration of marbofloxacin at a dosage of 5 mg/kg, PO, every 24 hours is recommended for rabbits to control infections attributable to susceptible bacteria.

  11. Preclinical Study of Single-Dose Moxidectin, a New Oral Treatment for Scabies: Efficacy, Safety, and Pharmacokinetics Compared to Two-Dose Ivermectin in a Porcine Model

    PubMed Central

    Bernigaud, Charlotte; Aho, Ludwig Serge; Dreau, Dominique; Kelly, Andrew; Sutra, Jean-François; Moreau, Francis; Lilin, Thomas; Botterel, Françoise; Guillot, Jacques; Chosidow, Olivier

    2016-01-01

    Background Scabies is one of the commonest dermatological conditions globally; however it is a largely underexplored and truly neglected infectious disease. Foremost, improvement in the management of this public health burden is imperative. Current treatments with topical agents and/or oral ivermectin (IVM) are insufficient and drug resistance is emerging. Moxidectin (MOX), with more advantageous pharmacological profiles may be a promising alternative. Methodology/Principal Findings Using a porcine scabies model, 12 pigs were randomly assigned to receive orally either MOX (0.3 mg/kg once), IVM (0.2 mg/kg twice) or no treatment. We evaluated treatment efficacies by assessing mite count, clinical lesions, pruritus and ELISA-determined anti-S. scabiei IgG antibodies reductions. Plasma and skin pharmacokinetic profiles were determined. At day 14 post-treatment, all four MOX-treated but only two IVM-treated pigs were mite-free. MOX efficacy was 100% and remained unchanged until study-end (D47), compared to 62% (range 26–100%) for IVM, with one IVM-treated pig remaining infected until D47. Clinical scabies lesions, pruritus and anti-S. scabiei IgG antibodies had completely disappeared in all MOX-treated but only 75% of IVM-treated pigs. MOX persisted ~9 times longer than IVM in plasma and skin, thereby covering the mite’s entire life cycle and enabling long-lasting efficacy. Conclusions/Significance Our data demonstrate that oral single-dose MOX was more effective than two consecutive IVM-doses, supporting MOX as potential therapeutic approach for scabies. PMID:27732588

  12. Prescription opioids. III. Disposition of oxycodone in oral fluid and blood following controlled single-dose administration.

    PubMed

    Cone, Edward J; DePriest, Anne Z; Heltsley, Rebecca; Black, David L; Mitchell, John M; LoDico, Charles; Flegel, Ron

    2015-04-01

    Oxycodone (OC) is recommended to be included as an analyte tested in the proposed Substance Abuse and Mental Health Services Administration (SAMHSA's) Mandatory Guidelines for Federal Workplace Drug Testing Programs using Oral Fluid (OF) Specimens. This study demonstrates the time course of OC and metabolites, noroxycodone (NOC), oxymorphone (OM) and noroxymorphone (NOM), in near-simultaneous paired OF and whole blood (BL) specimens by liquid chromatography-tandem mass spectrometry (LC-MS-MS) (limit of detection = 1 ng/mL OF, 5 ng/mL BL). A single dose of OC 20 mg controlled-release was administered to 12 healthy subjects followed by specimen collections for 52 h. Analyte prevalence was as follows: OF, OC > NOC > OM; and BL, OC > NOC > NOM. OC and NOC were frequently detected within 15-30 min in OF and 30 min to 2 h in BL. NOM and OM appeared between 1.5-5 h post-dose. The mean OF-to-BL (OF:BL) ratios and correlations were 5.4 for OC (r = 0.719) and 1.0 for NOC (r = 0.651). The period of detection for OF exceeded BL by ∼2-fold at similar cutoff concentrations. At a 1 ng/mL cutoff for OF, the mean detection time was 34 h for OC and NOC. These data provide new information that should facilitate interpretation of OC test results.

  13. Single oral dose pharmacokinetics of decursin, decursinol angelate, and decursinol in rats.

    PubMed

    Li, Li; Zhang, Jinhui; Xing, Chengguo; Kim, Sung-Hoon; Lü, Junxuan

    2013-03-01

    Decursin and decursinol angelate are the major components in the alcoholic extract of the root of Angelica gigas Nakai. Our previous work convincingly demonstrated that both decursin and decursinol angelate were rapidly converted to decursinol in mice after administration by either oral gavage or i. p. injection. In the current study, we compared for the first time the plasma profiles of decursinol, when equal moles of decursin/decursinol angelate or decursinol were given to rats by oral gavage, and investigated the effect of different formulas and other chemicals in Angelica gigas extract on the bioavailability of decursinol. Our results show that gavage of decursinol led to a faster attainment of plasma decursinol peak (Tmax ~ 0.7 h) and much higher peak levels than an equal molar amount administered as decursin/decursinol angelate mixture or as Angelica gigas ethanol extract, resulting in 2-3 fold higher bioavailability as estimated by the area under the curve of the respective regimens (65 012 vs. 27 033 h · ng/mL for decursinol and decursin/decursinol angelate treatment groups, respectively). Compared to a formula based on ethanol-PEG400-Tween80, carboxyl methyl cellulose was a less optimized vehicle. In addition, we detected peak levels of decursin and decursinol angelate in the plasma of rats administered with decursin/decursinol angelate or Angelica gigas extract in the nM range (Tmax ~ 0.5 h) with a newly established sensitive UHPLC-MS/MS method. Furthermore, our data support the liver, instead of intestine, as a major organ site where decursin and decursinol angelate were hydrolyzed to decursinol with a S9 microsomal in vitro metabolism assay. Taken together, our study provided important PK, LC-MS/MS methodology, formulation and metabolism insights in a rodent model for the rational design of in vivo efficacy studies of the corresponding chemicals in the future.

  14. Estimates of dose to systematic organs and GI tract based on data from miniature swine orally intubated with a single dose of Am-241 citrate

    SciTech Connect

    Bernard, S.R.; Nestor, C.W. Jr.; Eisele, G.R.; Eckerman, K.F.

    1982-01-01

    A model is presented for the internal radiation dose to the small intestine wall of miniature swine given Americium 241 citrate by oral intubation. The model incorporates the uptake of the Am-241 by the intestinal wall. About equal contributions of dose to the small intestine were observed from the intestinal contents and the wall itself. (ACR)

  15. Urinary bactericidal activity and pharmacokinetics of enoxacin versus norfloxacin and ciprofloxacin in healthy volunteers after a single oral dose.

    PubMed

    Well, M; Naber, K G; Kinzig-Schippers, M; Sörgel, F

    1998-04-01

    In an open, randomised monocentric crossover study in six male and six female healthy volunteers, the urinary antibacterial activity and pharmacokinetics of enoxacin, norfloxacin and ciprofloxacin were assessed. Urine was collected up to 6 days, and venous blood samples up to 12 h, after a single oral dose of 400 mg enoxacin, 400 mg norfloxacin and 500 mg ciprofloxacin. Enoxacin (250 mg/l) demonstrated the highest peak concentration (median) in the urine (0-6 h), followed by ciprofloxacin (237 mg/l) and norfloxacin (157 mg/l) as determined by the HPLC assay. The total amount (mean) excreted by the kidneys as parent drugs were as follows: enoxacin 54% of dose, ciprofloxacin 33% of dose, and norfloxacin 22% of dose. The mean plasma concentrations decreased from 1 to 4 h after administration for enoxacin from 1.9 to 1.4 mg/l, for ciprofloxacin from 2.0 to 0.8 mg/l and for norfloxacin from 1.3 to 0.5 mg/l. The antibacterial activity in urine was determined as urinary bactericidal titers (UBT), i.e. the highest 2-fold dilution of urine still bactericidal for the reference organism (E. coli ATCC 25,922) and for five uropathogens with minimal inhibitory (MIC) and bactericidal (MBC) concentrations ranging from highly susceptible to resistant cultured from the urine of patients with complicated urinary tract infections (UTI). For the E. coli ATCC 25,922, the organism with the lowest MIC, median UBTs of ciprofloxacin were present for 4 days, decreasing from 1:512 to 1:2, that of enoxacin for 2 days, decreasing from 1:256 to 1:4, and that of norfloxacin for 2 days, decreasing from 1:128 to 1:2. For the five uropathogens (with increasing MICs: K. pneumoniae, P. mirabilis, E. coli (resistant to nalidixic acid), P. aeruginosa and E. faecalis), the UBTs decreased in general, according to MICs, demonstrating the same relations of UBTs for ciprofloxacin (highest) versus enoxacin (medium) versus norfloxacin (lowest) with one exception (P. mirabilis) for which norfloxacin showed

  16. Pharmacokinetics of single oral dose of pimobendan in Hispaniolan Amazon parrots (Amazona ventralis).

    PubMed

    Guzman, David Sanchez-Migallon; Beaufrère, Hugues; KuKanich, Butch; Barker, Steven A; Brandão, João; Paul-Murphy, Joanne; Tully, Thomas N

    2014-06-01

    Pimobendan is a phosphodiesterase (PDE) inhibitor and calcium sensitizer with inotropic, lusitropic, and rasodilator properties used in the treatment of congestive heart failure. The mechanism of action is by inhibition of PDE III and V and by increasing intracellular calcium sensitivity in the cardiac myocardium. Pharmacokinetic and pharmacodynamic studies have been published in humans, dogs, and cats, but there are no studies in avian species. Pimobendan has been used in birds at the empirical dosage of 0.25 mg/kg q12h. To determine the pharmacokinetic parameters of pimobendan in Hispaniolan Amazon parrots (Amazona ventralis), 3 pilot studies with 2 birds, each receiving 1, 3, and 10 mg/kg PO, provided the basis for the pivotal trials with 6 birds, each receiving 10 mg/kg PO using 2 different suspensions. Blood samples were obtained at 0, 0.5, 1, 1.5, 2, 3, 4, 8, 12, and 18 hours after drug administration. Plasma concentrations were determined by liquid chromatography-tandem mass spectrometry (HPLC/MS) by use of electrospray ionization. Because of the erratic and low concentrations of pimobendan, pharmacokinetic parameters were calculated using naive averaged analysis. Plasma concentrations after commercial pimobendan tablet suspension at 10 mg/kg reached a Cmax of 8.26 ng/mL at 3 hours with a terminal half-life of 2.1 hours, while concentrations after the bulk chemical suspension reached a Cmax of 1.28 ng/mL at 12 hours and had a terminal half-life of 2.3 hours. Further studies evaluating the effect of oral pimobendan in parrots are needed.

  17. Antimalarial Preclinical Drug Development: A Single Oral Dose of A 5-Carbon-linked Trioxane Dimer Plus Mefloquine Cures Malaria-Infected Mice.

    PubMed

    Moon, Deuk Kyu; Singhal, Vandana; Kumar, Nirbhay; Shapiro, Theresa A; Posner, Gary H

    2009-01-01

    Three new 5-carbon-linked trioxane dimer carboxylate esters have been prepared from the natural trioxane, artemisinin in only 3-steps and 40-50% overall yields. Each one of these new chemical entities is at least as efficacious as the clinically used trioxane antimalarial drug artemether when combined with mefloquine hydrochloride in a low single oral dose cure. PMID:20686674

  18. Single oral doses of (±) 3,4-methylenedioxymethamphetamine ('Ecstasy') produce lasting serotonergic deficits in non-human primates: relationship to plasma drug and metabolite concentrations.

    PubMed

    Mueller, Melanie; Yuan, Jie; McCann, Una D; Hatzidimitriou, George; Ricaurte, George A

    2013-05-01

    Repeated doses of the popular recreational drug methylenedioxymethamphetamine (MDMA, 'Ecstasy') are known to produce neurotoxic effects on brain serotonin (5-HT) neurons but it is widely believed that typical single oral doses of MDMA are free of neurotoxic risk. Experimental and therapeutic trials with MDMA in humans are underway. The mechanisms by which MDMA produces neurotoxic effects are not understood but drug metabolites have been implicated. The aim of the present study was to assess the neurotoxic potential of a range of clinically relevant single oral doses of MDMA in a non-human primate species that metabolizes MDMA in a manner similar to humans, the squirrel monkey. A secondary objective was to explore the relationship between plasma MDMA and metabolite concentrations and lasting serotonergic deficits. Single oral doses of MDMA produced lasting dose-related serotonergic neurochemical deficits in the brains of squirrel monkeys. Notably, even the lowest dose of MDMA tested (5.7 mg/kg, estimated to be equivalent to 1.6 mg/kg in humans) produced significant effects in some brain regions. Plasma levels of MDMA engendered by neurotoxic doses of MDMA were on the order of those found in humans. Serotonergic neurochemical markers were inversely correlated with plasma concentrations of MDMA, but not with those of its major metabolites, 3,4-dihydroxymethamphetamine and 4-hydroxy-3-methoxymethamphetamine. These results suggest that single oral doses of MDMA in the range of those used by humans pose a neurotoxic risk and implicate the parent compound (MDMA), rather than one of its metabolites, in MDMA-induced 5-HT neural injury.

  19. Novel and Distinct Metabolites Identified Following a Single Oral Dose of Alpha- or Gamma-Hexabromocyclododecane in Mice

    EPA Science Inventory

    The metabolism of alpha- and gamma-hexabromocyclododecane (HBCD) was investigated in adult C57BL/6 female mice. Alpha- or gamma-[14C]HBCD (3 mg/kg bw) was orally administered with subsequent urine and feces collection for 4 consecutive days; a separate group of mice were dosed a...

  20. An alternative single dose parameter to avoid the need for steady-state studies on oral extended-release drug products.

    PubMed

    Paixão, Paulo; Gouveia, Luís F; Morais, José A G

    2012-02-01

    Use of single and multiple-dose studies is required to establish the bioequivalence between two extended-release oral dosage forms under the current European Guidelines. However, FDA is less strict in this regard and only requires a single-dose study. The objective of this work is to use a computer simulation in order to test the two approaches. Three pharmacokinetic models, representing different release mechanisms, were considered, and Monte Carlo simulations with intra- and inter-individual variabilities were performed. Five different bioequivalence protocols were used and a new pharmacokinetic metric -C(τ), the concentration at the end of the intended dosing interval obtained in the single-dose study - is proposed in order to avoid the need for steady-state studies while keeping the ability to detect differences between formulations. Results have shown that the European requirements are more capable to discriminate between two potentially different formulations but at the cost of the multiple-dose study and with an increased number of subjects when compared to the FDA requirements. However, the use of C(max) and AUC(0-)(t) obtained on a single-dose study with the added C(τ) metric equals the discriminatory ability of the current EMA requirements, without the need of a multiple-dose study. This proposed approach results in the reduction in the number of studies and volunteers enrolled in clinical bioequivalence trials, without compromising the quality assurance of a new extended-release oral formulation.

  1. Novel and Distinct Metabolites Identified Following a Single Oral Dose of α- or γ-Hexabromocyclododecane in Mice

    PubMed Central

    Szabo, David T.; Huwe, Janice; Diliberto, Janet; Birnbaum, Linda S.

    2013-01-01

    The metabolism of α- and γ-hexabromocyclododecane (HBCD) was investigated in adult C57BL/6 female mice. α- or γ-[14C]HBCD (3 mg/kg bw) was orally administered with subsequent urine and feces collection for 4 consecutive days; a separate group of mice were dosed and sacrificed 3 hours post-exposure to investigate tissue metabolite levels. Extractable and non-extractable HBCD metabolites were quantitated in liver, blood, fat, brain, bile, urine and feces and characterized by LC/MS (ESI-). Metabolites identified were distinct between the two stereoisomers. In mice exposed to α-HBCD, four hydroxylated metabolites were detected in fecal extracts, and one of these metabolite isomers was consistently characterized in liver, brain, and adipose tissue extracts. In contrast, mice exposed to γ-HBCD contained multiple isomers of monohydroxy-pentabromocyclododecene, dihydroxy-pentabromocyclododecene, and dihydroxy-pentabromocyclododecadiene in the feces while only a single monohydroxy-pentabromocyclododecane metabolite was measured in liver and adipose tissue. Both stereoisomers were transformed to metabolites which formed covalent bonds to proteins and/or lipids in the gut as evidenced by high fecal non-extractables. Although the potential toxicity of these free and bound metabolites remains to be determined, the presence of distinct metabolic products from the two main HBCD stereoisomers should allow biomarkers to be selected that may aid in characterizing sources of HBCD exposure. PMID:23171393

  2. Single-dose oral fluconazole versus topical clotrimazole in patients with pityriasis versicolor: A double-blind randomized controlled trial.

    PubMed

    Dehghan, Mohammad; Akbari, Negin; Alborzi, Nazila; Sadani, Somayeh; Keshtkar, Abas A

    2010-08-01

    This study was designed to compare the therapeutic effects of topical clotrimazole and systemic fluconazole in pityriasis versicolor. A double-blind randomized controlled trial was carried out in the dermatological clinic of Gorgan, northern Iran, between April 2006 and May 2007. All consecutive patients with pityriasis versicolor were included and randomly divided into two groups. In the first group (G1), patients underwent treatment with a single dose of fluconazole capsule (400 mg) and placebo cream. In the second group (G2), patients underwent treatment with clotrimazole cream (twice daily) and placebo capsule. The course of treatment was 2 weeks. All subjects were re-evaluated 2, 4 and 12 weeks after the end of the therapeutic course. After 2 weeks, the rate of complete resolution of disease was significantly higher in G2 than G1 (49.1% vs 30%). After 4 weeks, 41 patients (81.2%) of G1 and 52 patients (94.9%) of G2 showed complete resolution. After 12 weeks, 46 patients (92%) in G1 and 45 patients (81.8%) in G2 showed complete resolution. Recurrence rate in G1 and G2 were 6% and 18.2%, respectively. No complications were seen in either group. In this study, clinical response at week 4 was greater in the clotrimazole group than the fluconazole group. Recurrence at week 12 after treatment was less with oral fluconazole than clotrimazole cream. So, for better evaluation, more studies need to be done.

  3. A high performance liquid chromatographic assay of Mefloquine in saliva after a single oral dose in healthy adult Africans

    PubMed Central

    2012-01-01

    Background Mefloquine-artesunate is a formulation of artemisinin based combination therapy (ACT) recommended by the World Health Organization and historically the first ACT used clinically. The use of ACT demands constant monitoring of therapeutic efficacies and drug levels, in order to ensure that optimum drug exposure is achieved and detect reduced susceptibility to these drugs. Quantification of anti-malarial drugs in biological fluids other than blood would provide a more readily applicable method of therapeutic drug monitoring in developing endemic countries. Efforts in this study were devoted to the development of a simple, field applicable, non-invasive method for assay of mefloquine in saliva. Methods A high performance liquid chromatographic method with UV detection at 220 nm for assaying mefloquine in saliva was developed and validated by comparing mefloquine concentrations in saliva and plasma samples from four healthy volunteers who received single oral dose of mefloquine. Verapamil was used as internal standard. Chromatographic separation was achieved using a Hypersil ODS column. Results Extraction recoveries of mefloquine in plasma or saliva were 76-86% or 83-93% respectively. Limit of quantification of mefloquine was 20 ng/ml. Agreement between salivary and plasma mefloquine concentrations was satisfactory (r = 0.88, p < 0.001). Saliva:plasma concentrations ratio was 0.42. Conclusion Disposition of mefloquine in saliva paralleled that in plasma, making salivary quantification of mefloquine potentially useful in therapeutic drug monitoring. PMID:22369125

  4. Single dose oral amoxycillin 3 g with either 125 mg or 250 mg clavulanic acid to treat uncomplicated anogenital gonorrhoea.

    PubMed Central

    Lawrence, A G; Shanson, D C

    1985-01-01

    A single supervised oral dose of amoxycillin 3 g combined with clavulanic acid 125 mg as a suspension (Augmentin 3.125G) plus probenecid 1 g, cured 97 of 100 assessable patients who had uncomplicated anogenital gonorrhoea. Thirteen of the 100 patients were infected with penicillinase producing strains of Neisseria gonorrhoeae (PPNG) and 11 (85%) of these patients were cured, including one infected with a PPNG strain that was also resistant to spectinomycin. Another group of 93 assessable patients was treated with ampicillin 3 g plus probenecid 1 g, and only 85 (91%) patients were cured. Of the eight treatment failures in this group, five were found to be infected with PPNG strains. In a second study 144 assessable patients were treated with amoxycillin 3 g combined with clavulanic acid 250 mg, (Augmentin 3.250G) plus probenecid 1 g, and a 97% cure rate was again obtained. Five of seven (71%) patients infected with PPNG strains were cured. Although both Augmentin regimens were effective for treating gonorrhoea caused by PPNG and non-PPNG strains, side effects were noted in more patients treated with 250 mg clavulanic acid (24%) than with 125 mg clavulanic acid (5%). In addition, a similar cure rate was obtained in the three primary sites of infection, the urethra, cervix, and rectum. PMID:4007860

  5. Nutrition Composition and Single, 14-Day and 13-Week Repeated Oral Dose Toxicity Studies of the Leaves and Stems of Rubus coreanus Miquel.

    PubMed

    Om, Ae-Son; Song, Yu-Na; Noh, GeonMin; Kim, HaengRan; Choe, JeongSook

    2016-01-08

    The leaves and stems of the plant Rubus coreanus Miquel (RCMLS) are rich in vitamins, minerals and phytochemicals which have antioxidant, anti-hemolytic, anti-inflammatory, anti-fatigue and anti-cancer effects. However, RCMLS is not included in the Korean Food Standards Codex due to the lack of safety assurance concerning RCMLS. We evaluated single and repeated oral dose toxicity of RCMLS in Sprague-Dawley rats. RCMLS did not induce any significant toxicological changes in both male and female rats at a single doses of 2500 mg/kg/day. Repeated oral dose toxicity studies showed no adverse effects in clinical signs, body weight, food consumption, ophthalmic examination, urinalysis, hematology, serum biochemistry, necropsy findings, organ weight, and histopathology at doses of 625, 1250, and 2500 mg/kg/day. The LD50 and LOAEL of RCMLS might be over 2500 mg/kg body weight/day and no target organs were identified. Therefore, this study revealed that single and repeated oral doses of RCMLS are safe.

  6. Nutrition Composition and Single, 14-Day and 13-Week Repeated Oral Dose Toxicity Studies of the Leaves and Stems of Rubus coreanus Miquel.

    PubMed

    Om, Ae-Son; Song, Yu-Na; Noh, GeonMin; Kim, HaengRan; Choe, JeongSook

    2016-01-01

    The leaves and stems of the plant Rubus coreanus Miquel (RCMLS) are rich in vitamins, minerals and phytochemicals which have antioxidant, anti-hemolytic, anti-inflammatory, anti-fatigue and anti-cancer effects. However, RCMLS is not included in the Korean Food Standards Codex due to the lack of safety assurance concerning RCMLS. We evaluated single and repeated oral dose toxicity of RCMLS in Sprague-Dawley rats. RCMLS did not induce any significant toxicological changes in both male and female rats at a single doses of 2500 mg/kg/day. Repeated oral dose toxicity studies showed no adverse effects in clinical signs, body weight, food consumption, ophthalmic examination, urinalysis, hematology, serum biochemistry, necropsy findings, organ weight, and histopathology at doses of 625, 1250, and 2500 mg/kg/day. The LD50 and LOAEL of RCMLS might be over 2500 mg/kg body weight/day and no target organs were identified. Therefore, this study revealed that single and repeated oral doses of RCMLS are safe. PMID:26760987

  7. Single-dose oral quercetin improves redox status but does not affect heat shock response in mice.

    PubMed

    Chen, Yifan; Islam, Aminul; Abraham, Preetha; Deuster, Patricia

    2014-07-01

    Inflammation and oxidative stress are considered as likely contributors to heat injury. However, their roles in regulating the heat shock response in vivo remain unclear. We tested the hypothesis that acute quercetin treatment would improve redox status and reduce heat shock responses in mice. Mice underwent two heat tests before and after single oral administration of either quercetin (15 mg/kg) or vehicle. We measured physiologic and biochemical responses in mice during and 18 to 22 hours after heat tests, respectively. There were no significant differences in core temperature, heart rate, or blood pressure between quercetin and vehicle groups during heat exposure. Mice with relatively severe hyperthermia during the pretreatment heat test showed a significant trend toward a lower peak core temperature during the heat test after quercetin treatment. Compared with mice not exposed to heat, quercetin-treated mice had significantly lower interleukin 6 (P < .01) and higher superoxide dismutase levels (P < .01), whereas vehicle-treated mice had significantly lower total glutathione and higher 8-isoprostane levels in the circulation after heat exposure. Heat exposure significantly elevated heat shock proteins (HSPs) 72 and 90 and heat shock factor 1 levels in mouse liver, heart, and skeletal muscles, but no significant differences in tissue HSPs and heat shock factor 1 were found between quercetin- and vehicle-treated mice. These results suggest that a single moderate dose of quercetin is sufficient to alter redox status but not heat stress response in mice. Acute adaptations of peripheral tissues to heat stress may not be mediated by systemic inflammatory and redox state in vivo.

  8. The pharmacokinetics of a single oral or rectal dose of concurrently administered isoniazid, rifampin, pyrazinamide, and ethambutol in Asian elephants (Elephas maximus).

    PubMed

    P Brock, A; Isaza, R; Egelund, E F; Hunter, R P; Peloquin, C A

    2014-10-01

    Tuberculosis, caused by Mycobacterium tuberculosis, is a disease of concern in captive Asian elephants (Elephas maximus). Treatment for tuberculosis in elephants utilizes multidrug protocols combining isoniazid, rifampin, pyrazinamide, and/or ethambutol. In this study, a single, coformulated dose of isoniazid 5 mg/kg, rifampin 10 mg/kg, pyrazinamide 30 mg/kg, and ethambutol 30 mg/kg was administered orally to six Asian elephants, and rectally to five elephants using a cross-over design. Blood samples were collected serially over 24 h. Pyrazinamide and ethambutol concentrations were determined using validated gas chromatography assays. Isoniazid and rifampin concentrations were determined using validated high-performance liquid chromatography assays. Rectal isoniazid produced an earlier Tmax compared with oral administration. Oral isoniazid resulted in a comparatively lower Cmax , but higher AUC values compared with rectal isoniazid. Oral rifampin and oral ethambutol were well absorbed while rectal rifampin was not. Oral pyrazinamide produced comparatively higher Cmax and AUC values compared with rectal pyrazinamide. Results of this study indicate that currently recommended therapeutic monitoring sample collection times for rectal isoniazid and oral rifampin do not provide an accurate assessment of exposure for these drugs. This study demonstrates notable individual variability, indicating that dosing of these medications requires individual monitoring and provides additional information to guide the clinician when treating elephants.

  9. The pharmacokinetics of a single oral or rectal dose of concurrently administered isoniazid, rifampin, pyrazinamide, and ethambutol in Asian elephants (Elephas maximus).

    PubMed

    P Brock, A; Isaza, R; Egelund, E F; Hunter, R P; Peloquin, C A

    2014-10-01

    Tuberculosis, caused by Mycobacterium tuberculosis, is a disease of concern in captive Asian elephants (Elephas maximus). Treatment for tuberculosis in elephants utilizes multidrug protocols combining isoniazid, rifampin, pyrazinamide, and/or ethambutol. In this study, a single, coformulated dose of isoniazid 5 mg/kg, rifampin 10 mg/kg, pyrazinamide 30 mg/kg, and ethambutol 30 mg/kg was administered orally to six Asian elephants, and rectally to five elephants using a cross-over design. Blood samples were collected serially over 24 h. Pyrazinamide and ethambutol concentrations were determined using validated gas chromatography assays. Isoniazid and rifampin concentrations were determined using validated high-performance liquid chromatography assays. Rectal isoniazid produced an earlier Tmax compared with oral administration. Oral isoniazid resulted in a comparatively lower Cmax , but higher AUC values compared with rectal isoniazid. Oral rifampin and oral ethambutol were well absorbed while rectal rifampin was not. Oral pyrazinamide produced comparatively higher Cmax and AUC values compared with rectal pyrazinamide. Results of this study indicate that currently recommended therapeutic monitoring sample collection times for rectal isoniazid and oral rifampin do not provide an accurate assessment of exposure for these drugs. This study demonstrates notable individual variability, indicating that dosing of these medications requires individual monitoring and provides additional information to guide the clinician when treating elephants. PMID:24684601

  10. Single dose of diclofenac or meloxicam for control of pain, facial swelling, and trismus in oral surgery

    PubMed Central

    Orozco-Solís, Mariana; García-Ávalos, Yazmín; Pichardo-Ramírez, Celeste; Tobías-Azúa, Francisco; Zapata-Morales, Juan-Ramón; Aragon-Martínez, Othoniel-Hugo

    2016-01-01

    Background Postoperative pain associated with removal of mandibular third molars has been documented from moderate to severe during the first 24 hours after surgery, with pain peaking between 6 and 8 hours when a conventional local anesthetic is used. Dental pain is largely inflammatory, and evidence-based medicine has shown that nonsteroidal anti-inflammatory drugs are the best analgesics for dental pain. The aim of this study was to compare the analgesic, anti-inflammatory and anti-trismus effect of a single dose of diclofenac and meloxicam after mandibular third molar extraction. Material and Methods A total of 36 patients were randomized into two treatment groups, each with 18 patients, using a series of random numbers: Group A, was administered 100 mg of diclofenac; and Group B, 15 mg of meloxicam. Drugs were administered orally 1 hour prior to surgery. We evaluated pain intensity, analgesic consumption, swelling, as well as trismus. Results The results of this study showed that patients receiving 15 mg of meloxicam had less postoperative pain (P=0.04) and better aperture than those receiving 100 mg of diclofenac (P=0.03). The meloxicam group presented less swelling than diclofenac group; however, significant statistical differences were not observed. Conclusions Data of this double-blind, randomized, parallel-group clinical trial demonstrated that patients receiving 15 mg of preoperative meloxicam had a better postoperative analgesia and anti-trismus effect compared with who were given 100 mg of diclofenac after third molar extractions. Key words:Diclofenac, meloxicam, dental pain, trismus, third molar surgery. PMID:26615509

  11. Analysis of clinical efficacy, side effects, and laboratory changes among patients with acne vulgaris receiving single versus twice daily dose of oral isotretinoin.

    PubMed

    Ahmad, Hesham M

    2015-01-01

    Acne vulgaris is a debilitating disorder and requires proper treatment. This work evaluates the clinical efficacy, side effects, and laboratory changes of serum lipids and liver function during oral isotretinoin therapy for acne vulgaris, comparing single versus twice daily dose. Fifty-eight patients with acne vulgaris were included and randomized into group I (26 patients), who received once daily dose, and group II (32 patients), who received twice daily dose of oral isotretinoin. Global acne scoring system was used to evaluate acne severity and post-treatment improvement. Both regimens resulted in highly significant clinical improvement of acne with no significant difference. However, side effects were significantly more common among patients of group I. Both regimens caused mild rise of serum cholesterol, alanine transaminase (ALT), and aspartate aminotransferase (AST) with more prominent rise of triglycerides especially with twice daily dose. Oral isotretinoin is a very effective treatment for acne vulgaris with no statistically significant difference in clinical efficacy between once and twice daily doses. However, dividing dose to twice per day might cause fewer incidence of side effects without reducing clinical efficacy. The drug causes mild clinically insignificant rise of serum cholesterol, triglycerides, AST, and ALT.

  12. Evaluation of Sphingolipids in Wistar Rats Treated to Prolonged and Single Oral Doses of Fumonisin B1

    PubMed Central

    Direito, Glória M.; Almeida, Adriana P.; Aquino, Simone; dos Reis, Tatiana Alves; Pozzi, Claudia Rodrigues; Corrêa, Benedito

    2009-01-01

    The objective of the present study was to evaluate sphingolipid levels (sphingosine-So and sphinganine-Sa) and to compare the Sa/So ratio in liver, serum and urine of Wistar rats after prolonged administration (21 days) of fumonisin B1 (FB1). In parallel, the kinetics of sphingolipid elimination in urine was studied in animals receiving a single dose of FB1. Prolonged exposure to FB1 caused an increase in Sa levels in urine, serum and liver. The most marked effect on sphingolipid biosynthesis was observed in animals treated with the highest dose of FB1. Animals receiving a single dose of FB1 presented variations in Sa and So levels and in the Sa/So ratio. PMID:19333435

  13. Pharmacokinetics of Levetiracetam in Healthy Hispaniolan Amazon Parrots ( Amazona ventralis ) After Oral Administration of a Single Dose.

    PubMed

    Schnellbacher, Rodney; Beaufrère, Hugues; Vet, Dr Med; Arnold, Robert D; Tully, Thomas N; Mayer, Joerg; Divers, Stephen J

    2014-09-01

    Long-term anticonvulsive treatments have been poorly described in birds, and few pharmacokinetic studies have been performed, with mixed results. Levetiracetam, a new anticonvulsive drug, has shown good efficacy for monotherapy or adjunctive treatment of seizures in both human and veterinary medicine. To determine pharmacokinetics of levetiracetam in Hispaniolan Amazon parrots ( Amazona ventralis ), 20 healthy birds were randomly divided into 2 groups and administered either a 50 mg/kg (n = 10) or a 100 mg/kg (n = 10) oral dose of levetiracetam with no observable adverse effects. Blood samples were collected at baseline and at 12 time intervals (6 per group) for 16 hours. The concentration-time profiles resembled characteristic absorption, with maximum plasma concentrations of 61.0 μg/mL and 95.1 μg/mL at 60 minutes; terminal half-lives at 2.38 and 2.37 hours; volumes of distribution of 0.807 and 0.773 L/kg, with an area under the curve at 14 100 and 28 820 mg × min/L; and clearance rates of 3.65 and 3.60 mL/min per kg, respectively. Plasma concentrations were greater than 5.5 mg/L for up to 9.4 and 12 hours, suggesting an 8- and 12-hour oral dosing at 50 and 100 mg/kg, respectively, would be sufficient to maintain targeted values. Clinically, doses and frequencies may need escalation based on differences in species and individuals, and drug levels should be monitored.

  14. [Safety Evaluation of Rare Sugar Syrup: Single-dose Oral Toxicity in Rats, Reverse Mutation Assay, Chromosome Aberration Assay, and Acute Non-Effect Level for Diarrhea of a Single Dose in Humans].

    PubMed

    Yamada, Takako; Iida, Tetsuo; Takamine, Satoshi; Hayashi, Noriko; Okuma, Kazuhiro

    2015-01-01

    The safety of rare sugar syrup obtained from high-fructose corn syrup under slightly alkaline conditions was studied. Mutagenicity of rare sugar syrup was assessed by a reverse mutation assay using Salmonella typhimurium and Escherichia coli, and an in vitro chromosomal aberration assay using Chinese hamster lung cell line (CHL/IU). No mutagenicity of rare sugar syrup was detected under these experimental conditions. Oral administration of single dose (15,000 mg/kg) of rare sugar syrup to rats caused no abnormalities, suggesting no adverse effect of rare sugar syrup. In humans, the acute non-effect level of rare sugar syrup for causing diarrhea was estimated as 0.9 g/kg body weight as dry solid base in both males and females. PMID:26537651

  15. Pharmacokinetics of a single dose of intravenous and oral meloxicam in red-tailed hawks (Buteo jamaicensis) and great horned owls (Bubo virginianus).

    PubMed

    Lacasse, Claude; Gamble, Kathryn C; Boothe, Dawn M

    2013-09-01

    Pharmacokinetic data were determined after a single dose of meloxicam in red-tailed hawks (RTH; Buteo jamaicensis) and great horned owls (GHO; Bubo virginianus). In a nonrandomized crossover design, individual birds of each species received 1 dose of intravenous meloxicam (0.5 mg/kg i.v.; n = 7 for each species) followed by a 2-week washout period, and then each received 1 dose of oral meloxicam (0.5 mg/kg PO; n = 5 for each species). Blood samples were collected intermittently after administration, and meloxicam was detected in plasma by high-performance liquid chromatography. Time versus plasma concentration data were subjected to noncompartmental analysis. Red-tailed hawks were determined to have the shortest elimination half-life for meloxicam (0.49 +/- 0.5 hours) of any species documented. Great horned owls also eliminated meloxicam very rapidly (0.78 +/- 0.52 hours). Great horned owls achieved higher plasma concentrations (368 +/- 87 ng/mL) of meloxicam than RTH (182 +/- 167 ng/mL) after oral administration, although RTH had a markedly higher volume of distribution (832 +/- 711 mL/kg) than GHO (137.6 +/- 62.7 mL/kg). The differences in meloxicam pharmacokinetics between these 2 raptor species supports the need for species-dependent studies and underlines the challenges of extrapolating drug dosages between species. Results of this study suggest that the current recommended once-daily dosing interval of oral meloxicam is unlikely to maintain plasma concentrations anticipated to be therapeutic in either RTH or GHO, and practical dosing options are questionable for this nonsteriodal anti-inflammatory drug in these raptor species.

  16. Pharmacokinetics of a single dose of intravenous and oral meloxicam in red-tailed hawks (Buteo jamaicensis) and great horned owls (Bubo virginianus).

    PubMed

    Lacasse, Claude; Gamble, Kathryn C; Boothe, Dawn M

    2013-09-01

    Pharmacokinetic data were determined after a single dose of meloxicam in red-tailed hawks (RTH; Buteo jamaicensis) and great horned owls (GHO; Bubo virginianus). In a nonrandomized crossover design, individual birds of each species received 1 dose of intravenous meloxicam (0.5 mg/kg i.v.; n = 7 for each species) followed by a 2-week washout period, and then each received 1 dose of oral meloxicam (0.5 mg/kg PO; n = 5 for each species). Blood samples were collected intermittently after administration, and meloxicam was detected in plasma by high-performance liquid chromatography. Time versus plasma concentration data were subjected to noncompartmental analysis. Red-tailed hawks were determined to have the shortest elimination half-life for meloxicam (0.49 +/- 0.5 hours) of any species documented. Great horned owls also eliminated meloxicam very rapidly (0.78 +/- 0.52 hours). Great horned owls achieved higher plasma concentrations (368 +/- 87 ng/mL) of meloxicam than RTH (182 +/- 167 ng/mL) after oral administration, although RTH had a markedly higher volume of distribution (832 +/- 711 mL/kg) than GHO (137.6 +/- 62.7 mL/kg). The differences in meloxicam pharmacokinetics between these 2 raptor species supports the need for species-dependent studies and underlines the challenges of extrapolating drug dosages between species. Results of this study suggest that the current recommended once-daily dosing interval of oral meloxicam is unlikely to maintain plasma concentrations anticipated to be therapeutic in either RTH or GHO, and practical dosing options are questionable for this nonsteriodal anti-inflammatory drug in these raptor species. PMID:24344511

  17. A single, low, oral dose of a 5-carbon-linked trioxane dimer orthoester plus mefloquine cures malaria-infected mice.

    PubMed

    Moon, Deuk Kyu; Tripathi, Abhai; Sullivan, David; Siegler, Maxime A; Parkin, Sean; Posner, Gary H

    2011-05-01

    Four 5-carbon-linked trioxane dimer orthoesters (6a-6d) have been prepared in 4 or 5 chemical steps from the natural trioxane artemisinin (1). When administered orally to malaria-infected mice using a single dose of only 6 mg/kg body weight along with 18 mg/kg of mefloquine hydrochloride, trioxane dimer orthoester sulfone 6d completely and safely cured the mice; after 30 days, the cured mice showed no detectable parasitemia, gained at least as much weight as the control mice (no infection), and behaved normally. PMID:20952197

  18. [Pharmacokinetics and relative bioavailability of THC and THC-solid dispersion orally to mice at single dose].

    PubMed

    Liao, Li; Hua, Hua; Zhao, Jun-Ning; Luo, Heng; Yang, An-Dong

    2014-03-01

    To establish a fast sensitive, reproducible LC-MS/MS method to study pharmacokinetic properties of THC, and compare relative bioavailability of THC and its solid dispersion in mice. 200 mice were divided randomly into two groups, and administered orally with THC and THC-solid dispersion after fasting (calculate on THC:400 mg x kg(-1)), used HPLC-MS/MS method to determine the THC concentration of each period at the following times: baseline ( predose ), 15, 30, 45 min, 1, 1.5, 2, 3, 4, 6, 24 h after dosing. Calculating the pharmacokinetic parameters according to the C-t curv, and then use the Phoenix WinNonlin software for data analysis. The calibration curves were linear over the range 9.06-972 microg x L(-1) for THC (R2 = 0.999). The limit of detection (LOD) was 0.7 microg x L(-1), respectively. The average extraction recoveries for THC was above 75%, The methodology recoveries were between 79% and 108%. The intra-day and inter-day RSD were less than 13%, the stability test showed that the plasma samples was stable under different conditions (RSD < 15%). The precision, accuracy, recovery and applicability were found to be adequate for pharmacokinetic studies. Pharmacokinetic parameters of THC and THC-solid dispersion orally to mice shows as fllows: T(max), were 60 and 15 min, AUC(0-t) were 44 500.43 and 57 497.81 mg x L(-1) x min, AUC(0-infinity) were 51 226.00 and 68 031.48 mg x L(-1) x min, MRT(0-infinity) were 596.915 6, 661.747 7 min, CL(z)/F were 0.007 809 and 0.005 88 L x min(-1) x kg(-1). Compared with THC, the MRT and t1/2 of the THC-solid dispersion were all slightly extended, the t(max) was significantly reduced, AUC(0-24 h), AUC(0-infinity) and C(max) were all significantly higher, the relative bioavailability of THC-solid dispersion is 1.34 times of THC. The results of the experiment shows that the precision, accuracy, recovery and applicability were found to be adequate for the pharmacokinetic studies. After oral administration to mice, the relative

  19. [Pharmacokinetics and relative bioavailability of THC and THC-solid dispersion orally to mice at single dose].

    PubMed

    Liao, Li; Hua, Hua; Zhao, Jun-Ning; Luo, Heng; Yang, An-Dong

    2014-03-01

    To establish a fast sensitive, reproducible LC-MS/MS method to study pharmacokinetic properties of THC, and compare relative bioavailability of THC and its solid dispersion in mice. 200 mice were divided randomly into two groups, and administered orally with THC and THC-solid dispersion after fasting (calculate on THC:400 mg x kg(-1)), used HPLC-MS/MS method to determine the THC concentration of each period at the following times: baseline ( predose ), 15, 30, 45 min, 1, 1.5, 2, 3, 4, 6, 24 h after dosing. Calculating the pharmacokinetic parameters according to the C-t curv, and then use the Phoenix WinNonlin software for data analysis. The calibration curves were linear over the range 9.06-972 microg x L(-1) for THC (R2 = 0.999). The limit of detection (LOD) was 0.7 microg x L(-1), respectively. The average extraction recoveries for THC was above 75%, The methodology recoveries were between 79% and 108%. The intra-day and inter-day RSD were less than 13%, the stability test showed that the plasma samples was stable under different conditions (RSD < 15%). The precision, accuracy, recovery and applicability were found to be adequate for pharmacokinetic studies. Pharmacokinetic parameters of THC and THC-solid dispersion orally to mice shows as fllows: T(max), were 60 and 15 min, AUC(0-t) were 44 500.43 and 57 497.81 mg x L(-1) x min, AUC(0-infinity) were 51 226.00 and 68 031.48 mg x L(-1) x min, MRT(0-infinity) were 596.915 6, 661.747 7 min, CL(z)/F were 0.007 809 and 0.005 88 L x min(-1) x kg(-1). Compared with THC, the MRT and t1/2 of the THC-solid dispersion were all slightly extended, the t(max) was significantly reduced, AUC(0-24 h), AUC(0-infinity) and C(max) were all significantly higher, the relative bioavailability of THC-solid dispersion is 1.34 times of THC. The results of the experiment shows that the precision, accuracy, recovery and applicability were found to be adequate for the pharmacokinetic studies. After oral administration to mice, the relative

  20. Significance of higher drug concentration in erythrocytes of mice infected with Schistosoma japonicum and treated orally with mefloquine at single doses.

    PubMed

    Tao, Yi; Xue, Jian; Jiang, Bin; Zhang, Hao-Bing; Xiao, Shu-Hua

    2015-12-01

    The purpose of the present study is to understand the pharmacokinetic feature of mefloquine measured by erythrocytes and plasma in Schistosoma japonicum (S. j.)-infected mice and non-infected mice after oral administration of the drug at single doses. A high-performance liquid chromatography (HPLC) method was used to measure the plasma and erythrocyte concentrations of mefloquine at varying intervals posttreatment. Our results demonstrated that in non-infected mice treated orally with mefloquine at an ineffective dose of 50 mg/kg or effective dose of 200 mg/kg for 2-72 h, the erythrocyte-to-plasma ratios of mefloquine were 5.8-11.2 or 2-14.2. On the other hand, in S. j.-infected mice treated with the same single doses of the drug, the erythrocyte and plasma drug concentration ratios were 3.1-4.6 or 2.9-8.5, manifesting that either in infected mice or in non-infected mice that received oral mefloquine resulted in higher concentration of mefloquine in erythrocytes than that in plasma. Unexpectedly, under oral administration of mefloquine at a higher single dose of 200 mg/kg, the pharmacokinetic parameter C max values for plasma from S. j.-infected and non-infected mice were 1.6 ± 0.3 and 2.0 ± 0.4 μg/mL, respectively, which were below the determined in vitro LC50 (50 % lethal concentration) value of 4.93 μg/mL. Therefore, the plasma concentration of mefloquine may display a little effect against schistosomes during the treatment. Although the values of T 1/2 and AUC0-∞ for erythrocytes were significantly longer and higher in infected mice than those of corresponding non-infect mice that received the same single mefloqine dose of 50 mg/kg, the C max value was only 2.6 ± 0.4 μg/mL lower than the determined in vitro LC50, which may explain why this low single dose is ineffective against schistosomes in vivo. After administration of higher mefloquine dose of 200 mg/kg, the C max value for erythrocytes in infected mice was 30 % (7.4 ± 0

  1. Inter- and intra-individual variation in the metabolism of methaqualone in man after a single oral dose.

    PubMed

    Wilson, K; Reynolds, C N; Burnett, D

    1978-06-19

    The urinary excretion of five C-monohydroxy metabolites and the N-oxide metabolite of methaqualone in the 24 h period immediately after oral dosing with 250 mg methaqualone (Melsed) has been measured in ninteen healthy adults (13 male, 6 female) to assess interindividual variations and in five adults (3 male, 2 female) on five separate occasions to assess intraindividual variation. The overall importance of the six metabolites was 4'-hydroxy greater than N-oxide greater than 2'-hydroxymethyl greater than 3'-hydroxy greater than 6-hydroxy = 2-hydroxymethyl. Variations in this order both within the 24 h period and within each of the three eight-hour periods constituting the 24 hours were minor and variations in the absolute amount of each metabolie excreted ranged from two to three-fold. Intraindividual variations were generally smaller than interindividual variations and for each individual the pattern of metabolism was similar on the five occasions. There is evidence that the C-oxidation of methaqualone may be more sensitive to cyclical variations in hormone levels than is N-oxidation.

  2. Concurrent administration of donepezil HCl and sertraline HCl in healthy volunteers: assessment of pharmacokinetic changes and safety following single and multiple oral doses

    PubMed Central

    Nagy, Christa F; Kumar, Dinesh; Perdomo, Carlos A; Wason, Suman; Cullen, Edward I; Pratt, Raymond D

    2004-01-01

    Aim This study evaluated the safety and pharmacokinetics (PK) of donepezil HCl and sertraline HCl when administered separately and in combination. Methods This was a randomized, open-label, three-period crossover study. In consecutive dosing periods separated by washout periods of ≥3 weeks, healthy volunteers received either oral donepezil HCI 5 mg once daily for 15 days, oral sertraline HCl 50 mg once daily for 5 days followed by 10 days of once-daily sertraline HCl 100 mg, or the simultaneous administration of oral donepezil HCl and sertraline HCl. Plasma donepezil and sertraline concentrations were determined by high performance liquid chromatography/mass spectrometry. Safety was evaluated by physical and laboratory evaluations and the monitoring of adverse events (AEs). Results A total of 19 volunteers (16 male and three female) were enrolled. Three male subjects withdrew from the study prematurely due to AEs (one case of nausea/stomach cramps and one case of eosinophilia during combination treatment, and one upper respiratory tract infection during treatment with sertraline HCl alone). In subjects who completed all three treatment periods (n = 16), the concurrent administration of donepezil HCl and sertraline HCl did not alter the steady-state (day 15) PK parameters of donepezil HCl. A small (<12%) but statistically significant (P = 0.02) increase in donepezil Cmax was seen after single doses of sertraline HCl and donepezil HCl on day 1 but this was not thought to be clinically meaningful. No significant differences in the tmax or AUC0–24 h of donepezil were observed between the donepezil HCl only or donepezil HCl plus sertraline HCl groups on day 1. No significant changes in sertraline PK parameters were observed either on day 1 (single dose) or on day 15 (steady state) when sertraline HCl was co-administered with donepezil HCl. Generally, the concurrent administration of donepezil HCl and sertraline HCl was well tolerated, with no serious AEs reported

  3. Pharmacokinetics, pharmacodynamics and safety of single, oral doses of GSK1278863, a novel HIF-prolyl hydroxylase inhibitor, in healthy Japanese and Caucasian subjects.

    PubMed

    Hara, Katsutoshi; Takahashi, Naoki; Wakamatsu, Akira; Caltabiano, Stephen

    2015-12-01

    This study was performed to evaluate the pharmacokinetics (PK), pharmacodynamics (PD) and safety of GSK1278863, a novel prolyl hydroxylase inhibitor, following a single oral administration of GSK1278863 from 10 to 100 mg or placebo in Japanese (n = 19), and 10, 25 and 100 mg in Caucasians (n = 14). Dose-proportional increases were observed in AUCinf of GSK1278863 in both ethnic groups, with a 1.3-1.5-fold higher exposure seen in Japanese relative to Caucasians for all doses. This difference in exposure can be mainly explained by the observed differences in body weights between the two groups. Statistically significant increases in erythropoietin (EPO), vascular endothelial growth factor (VEGF) and reticulocyte counts were observed in Japanese subjects after the 50 and 100 mg dose as compared to placebo. In Caucasians, similar to Japanese, EPO and VEGF levels were observed to be increased in response to the 100 mg dose. Drug-related adverse events, including headache and abdominal pain were reported in 3 Japanese subjects, while headache was reported in 3 Caucasians. In conclusion, GSK1278863 was well tolerated, with dose-proportional increases in exposure observed in both groups. There was no evidence of ethnic differences between Japanese and Caucasian with regard to PK or PD.

  4. A single dose of oral DNA immunization delivered by attenuated Salmonella typhimurium down-regulates transgene expression in HBsAg transgenic mice.

    PubMed

    Zheng, Bo Jian; Ng, Mun Hon; Chan, Kwok Wah; Tam, Sidney; Woo, Patrick C Y; Ng, Sze Park; Yuen, Kwok Yung

    2002-11-01

    The efficacy of immunization with Salmonella typhimurium aroA to deliver the plasmid pRc/CMV-HBsAg (i.e. an oral DNA vaccine) was compared with that of intramuscular immunization with the same plasmid DNA, and with recombinant HBsAg protein, in a HBsAg transgenic mouse model. A single dose of oral DNA vaccine evoked vigorous Th1 cell and CTL responses and production of IgG2 subclass of anti-HBs after 2 weeks, and this was accompanied by a transient hepatitic flare with elevated alanine aminotransferase in the first 3 weeks. Concomitantly, the level of HBsAg-mRNA in liver tissues decreased by more than fourfold and viral-antigen expression was curtailed markedly in hepatocytes compared with controls. Hepatitic flare subsided after 3 weeks, but suppression of the transgene expression was continued in the absence of overt liver pathology for the remaining duration of the experiment (i.e. 12 weeks), and possibly beyond. The other vaccines could also break immune tolerance, but this was achieved only after repeated booster doses of the respective vaccines, and they did not affect transgene expression, or induce hepatic flare. We previously showed in non-transgenic mice that immunization by the oral DNA vaccine is achieved by an active intestinal infection with a bacterial carrier that is an adept intracellular parasite, and the immune response to the vaccination is orchestrated by phagocytic APC. Our present findings further implicated that the combined effects of an innate and a specific immune response induced by oral DNA vaccination are crucial in down-regulating HBsAg-transgene expression in hepatocytes.

  5. A pharmacokinetic and residual study of sulfadiazine/trimethoprim in mandarin fish (Siniperca chuatsi) with single- and multiple-dose oral administrations.

    PubMed

    Wang, W; Luo, L; Xiao, H; Zhang, R; Deng, Y; Tan, A; Jiang, L

    2016-06-01

    A pharmacokinetic and tissue residue study of sulfadiazine combined with trimethoprim (SDZ/TMP = 5/1) was conducted in Siniperca chuatsi after single- (120 mg/kg) or multiple-dose (an initial dose of 120 mg/kg followed by a 5-day consecutive dose of 60 mg/kg) oral administrations at 28 °C. The absorption half-life (t1/2α ), elimination half-life (t1/2β ), volume of distribution (Vd /F), and the total body clearance (ClB /F) for SDZ and TMP were 4.3 ± 1.7 to 6.3 ± 1.8 h and 2.4 ± 1.0 to 3.9 ± 0.9 h, 25.9 ± 4.5 to 53.0 ± 5.6 h and 11.8 ± 3.5 to 17.1 ± 3.4 h, 2.34 ± 0.78 to 3.67 ± 0.99 L/kg and 0.39 ± 0.01 to 1.33 ± 0.57 L/kg, and 0.03 ± 0.01 to 0.06 ± 0.01 L/kg·h and 0.02 ± 0.01 to 0.05 ± 0.01 L/kg·h, respectively, after the single dose. The elimination half-life (t1/2β ) and mean residue time (MRT) for SDZ and TMP were 68.8 ± 7.8 to 139.8 ± 12.3 h and 34.0 ± 5.5 to 56.1 ± 6.8 h, and 99.3 ± 6.1 to 201.7 ± 11.5 h and 49.1 ± 3.5 to 81.0 ± 5.1 h, respectively, after the multiple-dose administration. The daily oral SDZ/TMP administration might cause a high tissue concentration and long t1/2β , thereby affecting antibacterial activity. The withdrawal time for this oral SDZ/TMP formulation (according to the accepted guidelines in Europe for maximum residue limits, <0.1 mg/kg of tissues for sulfonamides, and <0.05 mg/kg for TMP) should not be <36 days for fish. PMID:26669806

  6. Safety and pharmacokinetics of single and multiple intravenous bolus doses of diclofenac sodium compared with oral diclofenac potassium 50 mg: A randomized, parallel-group, single-center study in healthy subjects.

    PubMed

    Munjal, Sagar; Gautam, Anirudh; Okumu, Franklin; McDowell, James; Allenby, Kent

    2016-01-01

    In a randomized, parallel-group, single-center study in 42 healthy adults, the safety and pharmacokinetic parameters of an intravenous formulation of 18.75 and 37.5 mg diclofenac sodium (DFP-08) following single- and multiple-dose bolus administration were compared with diclofenac potassium 50 mg oral tablets. Mean AUC0-inf values for a 50-mg oral tablet and an 18.75-mg intravenous formulation were similar (1308.9 [393.0]) vs 1232.4 [147.6]). As measured by the AUC, DFP-08 18.75 mg and 37.5 mg demonstrated dose proportionality for extent of exposure. One subject in each of the placebo and DFP-08 18.75-mg groups and 2 subjects in the DFP-08 37.5-mg group reported adverse events that were considered by the investigator to be related to the study drug. All were mild in intensity and did not require treatment. Two subjects in the placebo group and 1 subject in the DFP-08 18.75-mg group reported grade 1 thrombophlebitis; no subjects reported higher than grade 1 thrombophlebitis after receiving a single intravenous dose. The 18.75- and 37.5-mg doses of intravenous diclofenac (single and multiple) were well tolerated for 7 days. Additional efficacy and safety studies are required to fully characterize the product.

  7. Serum and urine concentrations of flunitrazepam and metabolites, after a single oral dose, by immunoassay and GC-MS.

    PubMed

    Snyder, H; Schwenzer, K S; Pearlman, R; McNally, A J; Tsilimidos, M; Salamone, S J; Brenneisen, R; ElSohly, M A; Feng, S

    2001-01-01

    A clinical study was conducted to assess the ability of commercially available immunoassays to detect flunitrazepam (FNP) in plasma and urine samples and to compare the results with those obtained by gas chromatography-mass spectrometry (GC-MS). The clinical study consisted of four individuals (two male and two female) who had taken a single 2-mg dose of FNP. Serum was collected over a 48-h period and urine was collected over a 72-h period. The serum and urine samples were analyzed by the COBAS INTEGRA Serum Benzodiazepines assay (SBENZ), the TDx serum and urine Benzodiazepines assay, and GC-MS. The GC-MS procedure was developed for analysis of FNP and metabolites in plasma and urine using an acid hydrolysis step resulting in the formation of specific benzophenones corresponding to FNP and its metabolites. The relative sensitivities of the assays for the detection of FNP and metabolites in serum and urine were GC-MS > SBENZ > TDx. The immunoassay results for serum samples showed peak concentrations of FNP metabolites at 8 h after FNP ingestion for three individuals and at about 1 h for the fourth individual. The GC-MS, SBENZ, and TDx urine immunoassays detected drug above the stated limit of detection (LOD) in 44, 41, and 35 serial FNP urine samples, respectively. FNP metabolites were detected in urine samples with all three assays for up to 72 h after a 2-mg dose. The improved detection rate with the SBENZ assay as compared to the TDx assay is likely explained by its higher cross-reactivity with the major metabolite, 7-amino-flunitrazepam (7-amino-FNP), and its lower LOD.

  8. Pharmacokinetics of a single oral dose of vitamin D3 (70,000 IU) in pregnant and non-pregnant women

    PubMed Central

    2012-01-01

    Background Improvements in antenatal vitamin D status may have maternal-infant health benefits. To inform the design of prenatal vitamin D3 trials, we conducted a pharmacokinetic study of single-dose vitamin D3 supplementation in women of reproductive age. Methods A single oral vitamin D3 dose (70,000 IU) was administered to 34 non-pregnant and 27 pregnant women (27 to 30 weeks gestation) enrolled in Dhaka, Bangladesh (23°N). The primary pharmacokinetic outcome measure was the change in serum 25-hydroxyvitamin D concentration over time, estimated using model-independent pharmacokinetic parameters. Results Baseline mean serum 25-hydroxyvitamin D concentration was 54 nmol/L (95% CI 47, 62) in non-pregnant participants and 39 nmol/L (95% CI 34, 45) in pregnant women. Mean peak rise in serum 25-hydroxyvitamin D concentration above baseline was similar in non-pregnant and pregnant women (28 nmol/L and 32 nmol/L, respectively). However, the rate of rise was slightly slower in pregnant women (i.e., lower 25-hydroxyvitamin D on day 2 and higher 25-hydroxyvitamin D on day 21 versus non-pregnant participants). Overall, average 25-hydroxyvitamin D concentration was 19 nmol/L above baseline during the first month. Supplementation did not induce hypercalcemia, and there were no supplement-related adverse events. Conclusions The response to a single 70,000 IU dose of vitamin D3 was similar in pregnant and non-pregnant women in Dhaka and consistent with previous studies in non-pregnant adults. These preliminary data support the further investigation of antenatal vitamin D3 regimens involving doses of ≤70,000 IU in regions where maternal-infant vitamin D deficiency is common. Trial registration ClinicalTrials.gov (NCT00938600) PMID:23268736

  9. Effect of feeding rate on biochemical measures and fate of a single oral dose of PCB in Arctic char

    SciTech Connect

    Delorme, P.D.; Brown, S.B.; Lockhart, W.L.; Metner, D.A.; Vandenbyllaardt, L.

    1995-12-31

    This study was done to determine the effects of reducing lipid stores and the resulting mobilization of associated contaminants. Individually tagged Arctic char (Saivelinus alpinus) were treated with single gavage doses of 6.1 ng/g {sup 14}C-3,3{prime}4,4{prime},5-pentachlorobiphenyl (PCB 126) in gelatin or vehicle (controls). Following treatment, the PCB was allowed 3 weeks to reach equilibrium distribution within the fish. After this 3 week period, treated and control groups of fish were fed one of three rations, (1.5%, 0.75% or 0.25% body wt/d). Fish were sampled at 0, 8, 24 and 48 weeks following the initiation of the different rations. PCB concentrations and lipid levels were measured in 5 tissues (muscle, liver, intestine, spleen and kidney). Biochemical response measured included hepatic EROD, retinoids and tocopherol. Growth was reduced in both treated and control groups fed the lowest ration. EROD activity was negatively correlated with growth and positively correlated with liver concentrations of PCB 126. Declines in mean lipid content were ration dependent. Changes in hepatic retinoids were related to both ration and treatment. The results indicate that a low ration resulted in greater utilization of stored lipids and higher tissue concentrations of contaminants compared to the other rations. These changes altered biochemical measures which are responsive to planar chlorinated aromatic hydrocarbons.

  10. PHARMACOKINETICS OF TRAMADOL HYDROCHLORIDE AND ITS METABOLITE O-DESMETHYLTRAMADOL FOLLOWING A SINGLE, ORALLY ADMINISTERED DOSE IN CALIFORNIA SEA LIONS (ZALOPHUS CALIFORNIANUS).

    PubMed

    Boonstra, Jennifer L; Barbosa, Lorraine; Van Bonn, William G; Johnson, Shawn P; Gulland, Frances M D; Cox, Sherry K; Martin-Jimenez, Tomas

    2015-09-01

    Tramadol is a synthetic, centrally acting, opiate-like analgesic that is structurally related to codeine and morphine. The objective of this study was to determine the pharmacokinetics of tramadol hydrochloride and its major active metabolite O-desmethyltramadol (M1) in the California sea lion (Zalophus californianus). A single dose of tramadol was administered orally in fish at 2 mg/kg to a total of 15 wild California sea lions admitted for rehabilitation. Twenty-four total blood samples were collected post drug administration at 10, 20, 30, and 45 min and at 1, 3, 5, 6, 8, 12, and 24 hr. Blood plasma was separated and stored at -80°C until analysis with high-performance liquid chromatography was performed to determine levels of tramadol and M1, the major active metabolite. The results indicate that the plasma levels of parent tramadol are low or negligible during the first 30-45 min and then reach the predicted mean maximum plasma concentration of 358 ng/ml at 1.52 hr. The M1 metabolite was not detectable in 21 of 24 plasma samples, below the level of quantification of 5 ng/ml in one sample, and detectable at 11 and 17 ng/ml in two of the samples. This study suggests that a 2 mg/kg dose would need to be administered every 6-8 hr to maintain concentrations of tramadol above the minimum human analgesic level for mild to moderate pain. Based on dosing simulations, a dose of 4 mg/kg q8 hr or q12 hr, on average, may represent an adequate compromise, but further studies are needed using a larger sample size. Pharmacodynamic studies are warranted to determine if tramadol provides analgesic effects in this species. The potential for tramadol toxicosis at any dose also has not been determined in this species. PMID:26352950

  11. PHARMACOKINETICS OF TRAMADOL HYDROCHLORIDE AND ITS METABOLITE O-DESMETHYLTRAMADOL FOLLOWING A SINGLE, ORALLY ADMINISTERED DOSE IN CALIFORNIA SEA LIONS (ZALOPHUS CALIFORNIANUS).

    PubMed

    Boonstra, Jennifer L; Barbosa, Lorraine; Van Bonn, William G; Johnson, Shawn P; Gulland, Frances M D; Cox, Sherry K; Martin-Jimenez, Tomas

    2015-09-01

    Tramadol is a synthetic, centrally acting, opiate-like analgesic that is structurally related to codeine and morphine. The objective of this study was to determine the pharmacokinetics of tramadol hydrochloride and its major active metabolite O-desmethyltramadol (M1) in the California sea lion (Zalophus californianus). A single dose of tramadol was administered orally in fish at 2 mg/kg to a total of 15 wild California sea lions admitted for rehabilitation. Twenty-four total blood samples were collected post drug administration at 10, 20, 30, and 45 min and at 1, 3, 5, 6, 8, 12, and 24 hr. Blood plasma was separated and stored at -80°C until analysis with high-performance liquid chromatography was performed to determine levels of tramadol and M1, the major active metabolite. The results indicate that the plasma levels of parent tramadol are low or negligible during the first 30-45 min and then reach the predicted mean maximum plasma concentration of 358 ng/ml at 1.52 hr. The M1 metabolite was not detectable in 21 of 24 plasma samples, below the level of quantification of 5 ng/ml in one sample, and detectable at 11 and 17 ng/ml in two of the samples. This study suggests that a 2 mg/kg dose would need to be administered every 6-8 hr to maintain concentrations of tramadol above the minimum human analgesic level for mild to moderate pain. Based on dosing simulations, a dose of 4 mg/kg q8 hr or q12 hr, on average, may represent an adequate compromise, but further studies are needed using a larger sample size. Pharmacodynamic studies are warranted to determine if tramadol provides analgesic effects in this species. The potential for tramadol toxicosis at any dose also has not been determined in this species.

  12. Kinetics and disposition of orally dosed sodium chlorate in sheep

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Experiments were conducted in sheep to determine excretory characteristics of sodium chlorate after a single oral dose. In Exp. 1 lambs (n = 16; age = 8.1 ± 1.7 d; BW = 8.2 ± 1.1 kg; mean ± SD) were dosed orally with 0, 30, 60, or 90 mg/kg BW of sodium chlorate. Twenty-four h after exposure chlorate...

  13. Effect of a single oral dose of milrinone on left ventricular diastolic performance in the failing human heart.

    PubMed

    Piscione, F; Jaski, B E; Wenting, G J; Serruys, P W

    1987-12-01

    In 14 patients with severe congestive heart failure, left ventricular pressure (measured by tip manometer) and derived variables were measured before and every 10 minutes after administration of oral milrinone (10 mg) for 50 minutes along with measurements of coronary sinus blood flow and drug plasma levels. Arterial and coronary sinus catecholamines were measured only before and 50 minutes after milrinone. Left ventricular pressure, volume (as determined by angiography) and derived indexes were simultaneously assessed at matched atrial paced heart rate before and 60 minutes after milrinone. Three patients who did not achieve a therapeutic plasma level (less than 150 ng/ml) were excluded. Peak negative first derivative of left ventricular pressure (-dP/dt) progressively and significantly increased (10%) together with a decrease in the two exponential time constants of relaxation, namely, Tau 1 (19%) and Tau 2 (22%), which represent the fit for and after the first 40 ms, respectively. Coronary flow significantly increased by 43% within 30 minutes, whereas the decrease (-13%) in coronary vascular resistance failed to be statistically significant. No change occurred in catecholamine concentrations after milrinone. Peak filling rate significantly increased by 15%. Pressure-volume curves showed a leftward and, in four patients, a downward shift; a significant decrease in minimal left ventricular diastolic and end-diastolic pressures (by 55 and 38%, respectively) and in end-diastolic volume (18%) occurred. The constant of elastic chamber stiffness measured by the simple elastic model tended to decrease, but failed to achieve a statistically significant level. Thus, oral milrinone improved left ventricular early relaxation and filling as well as chamber distensibility. This global improvement of diastolic function makes milrinone a potentially useful drug in the oral treatment of heart failure.

  14. Kinetics of the phthalate metabolites mono-2-ethylhexyl phthalate (MEHP) and mono-n-butyl phthalate (MnBP) in male subjects after a single oral dose.

    PubMed

    Mittermeier, Astrid; Völkel, Wolfgang; Fromme, Hermann

    2016-06-11

    Humans have been exposed to dialkyl ortho-phthalates for decades. Due to degradation the phthalate monoesters, responsible for the toxic effects, are additionally found in environmental media as well as food samples. Nevertheless, the toxicokinetic properties of the monoesters are not known. Therefore, metabolism of the phthalate monoesters mono-2-ethylhexyl phthalate (MEHP) and mono-n-butyl phthalate (MnBP) was studied in four male volunteers (23-58 years of age) after ingestion of a single dose of 50μg/kg bw D4-MEHP or 10μg/kg bw D4-MnBP. The main metabolites in urine were determined up to 46h after administration. In the MEHP-study, more than 90% of each metabolite appeared in the urine within the first 22h, and the average excreted amount of D4-MEHP and its four secondary metabolites was 62% of the administered dose. The highest value of 15% was observed for mono-2-ethyl-5-carboxy-pentyl phthalate (D4-5cx-MEPP). The mean elimination half-life of D4-MEHP was estimated to be 3.5±1.4h. In the MnBP-study, the total recovered values of D4-MnBP and its secondary metabolites ranged from 52% to 130%. The monoester itself, with a half-life of 1.9±0.5h, accounted for the majority of the ingested dose (92%), while the secondary metabolites D4-mono-3-hydroxy-n-butyl phthalate (D4-3OH-MnBP) and D4-3-carboxy-mono-propyl phthalate (D4-3cx-MPP) represented only 7.1% and 1.0% of the ingested dose, respectively. Overall, this study determined that the kinetics of the phthalate monoesters MEHP and MnBP after oral dosage are comparable to the properties of their diesters.

  15. Kinetics of the phthalate metabolites mono-2-ethylhexyl phthalate (MEHP) and mono-n-butyl phthalate (MnBP) in male subjects after a single oral dose.

    PubMed

    Mittermeier, Astrid; Völkel, Wolfgang; Fromme, Hermann

    2016-06-11

    Humans have been exposed to dialkyl ortho-phthalates for decades. Due to degradation the phthalate monoesters, responsible for the toxic effects, are additionally found in environmental media as well as food samples. Nevertheless, the toxicokinetic properties of the monoesters are not known. Therefore, metabolism of the phthalate monoesters mono-2-ethylhexyl phthalate (MEHP) and mono-n-butyl phthalate (MnBP) was studied in four male volunteers (23-58 years of age) after ingestion of a single dose of 50μg/kg bw D4-MEHP or 10μg/kg bw D4-MnBP. The main metabolites in urine were determined up to 46h after administration. In the MEHP-study, more than 90% of each metabolite appeared in the urine within the first 22h, and the average excreted amount of D4-MEHP and its four secondary metabolites was 62% of the administered dose. The highest value of 15% was observed for mono-2-ethyl-5-carboxy-pentyl phthalate (D4-5cx-MEPP). The mean elimination half-life of D4-MEHP was estimated to be 3.5±1.4h. In the MnBP-study, the total recovered values of D4-MnBP and its secondary metabolites ranged from 52% to 130%. The monoester itself, with a half-life of 1.9±0.5h, accounted for the majority of the ingested dose (92%), while the secondary metabolites D4-mono-3-hydroxy-n-butyl phthalate (D4-3OH-MnBP) and D4-3-carboxy-mono-propyl phthalate (D4-3cx-MPP) represented only 7.1% and 1.0% of the ingested dose, respectively. Overall, this study determined that the kinetics of the phthalate monoesters MEHP and MnBP after oral dosage are comparable to the properties of their diesters. PMID:27091076

  16. Comparison of intake and systemic relative effect potencies of dioxin-like compounds in female rats after a single oral dose.

    PubMed

    van Ede, Karin I; Andersson, Patrik L; Gaisch, Konrad P J; van den Berg, Martin; van Duursen, Majorie B M

    2014-03-01

    Risk assessment for mixtures of dioxin-like compounds uses the toxic equivalency factor (TEF) approach. Although current WHO-TEFs are mostly based on oral administration, they are commonly used to determine toxicity equivalencies (TEQs) in human blood or tissues. However, the use of "intake" TEFs to calculate systemic TEQs in for example human blood, has never been validated. In this study, intake and systemic relative effect potencies (REPs) for 1,2,3,7,8-pentachlorodibenzo-p-dioxin (PeCDD), 2,3,4,7,8-pentachlorodibenzofuran (4-PeCDF), 3,3',4,4',5-pentachlorobiphenyl (PCB-126), 2,3',4,4',5-pentachlorobiphenyl (PCB-118) and 2,3,3',4,4',5-hexachlorobiphenyl (PCB-156) were compared in rats. The effect potencies were calculated based on administered dose and liver, adipose or plasma concentrations in female Sprague-Dawley rats 3 days after a single oral dose, relative to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Hepatic ethoxyresorufin-O-deethylase activity and gene expression of Cyp1a1, 1a2, 1b1 and aryl hydrocarbon receptor repressor in liver and peripheral blood lymphocytes were used as endpoints. Results show that plasma-based systemic REPs were generally within a half log range around the intake REPs for all congeners tested, except for 4-PeCDF. Together with our previously reported systemic REPs from a mouse study, these data do not warrant the use of systemic REPs as systemic TEFs for human risk assessment. However, further investigation for plasma-based systemic REPs for 4-PeCDF is desirable.

  17. Odanacatib, a selective cathepsin K inhibitor to treat osteoporosis: safety, tolerability, pharmacokinetics and pharmacodynamics – results from single oral dose studies in healthy volunteers

    PubMed Central

    Stoch, S Aubrey; Zajic, Stefan; Stone, Julie A; Miller, Deborah L; Bortel, Lucas; Lasseter, Kenneth C; Pramanik, Barnali; Cilissen, Caroline; Liu, Qi; Liu, Lida; Scott, Boyd B; Panebianco, Deborah; Ding, Yu; Gottesdiener, Keith; Wagner, John A

    2013-01-01

    Aims To evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of odanacatib (ODN), a cathepsin K inhibitor, in humans. Methods Two double-blind, randomized, placebo-controlled, single oral dose studies were performed with ODN (2–600 mg) in 44 healthy volunteers (36 men and eight postmenopausal women). Results Adverse experiences (AEs) with single doses of ODN were transient and mild to moderate, with the exception of one severe AE of gastroenteritis. Headache was the most frequent AE. After absorption of ODN (initial peak concentrations 4–6 h postdose), plasma concentrations exhibited a monophasic decline, with an apparent terminal half-life of ∼40–80 h. The area under the curve0-24 hours (AUC0–24 h), concentration at 24 hours (C24 h) and maximum concentration (Cmax,overal) increased in a less than dose-proportional manner from 2 to 600 mg. Administration of ODN with a high-fat meal led to ∼100% increases in AUC0–24 h, Cmax,day1, Cmax,overall and C24 h relative to the fasted state, while administration with a low-fat meal led to a ∼30% increase in those parameters. Reduction of biomarkers of bone resorption, the C- and N-telopeptides of cross-links of type I collagen, (CTx and NTx, respectively), was noted at 24 h for doses ≥5 mg and at 168 h postdose for ≥10 mg. In postmenopausal women administered 50 mg ODN, reductions in serum CTx of −66% and urine NTx/creatinine (uNTx/Cr) of −51% relative to placebo were observed at 24 h. At 168 h, reductions in serum CTx (−70%) and uNTx/Cr (−78%) were observed relative to baseline. Pharmacokinetic/pharmacodynamic modeling characterized the ODN concentration/uNTx/Cr relation, with a modeled EC50 value of 43.8 nM and ∼80% maximal reduction. Conclusions Odanacatib was well tolerated and has a pharmacokinetic and pharmacodynamic profile suitable for once weekly dosing. PMID:23013236

  18. Comparison of Intake and Systemic Relative Effect Potencies of Dioxin-like Compounds in Female Mice after a Single Oral Dose

    PubMed Central

    Andersson, Patrik L.; Gaisch, Konrad P.J.; van den Berg, Martin; van Duursen, Majorie B.M.

    2013-01-01

    Background: Risk assessment for mixtures of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) is performed using the toxic equivalency factor (TEF) approach. These TEF values are derived mainly from relative effect potencies (REPs) linking an administered dose to an in vivo toxic or biological effect, resulting in “intake” TEFs. At present, there is insufficient data available to conclude that intake TEFs are also applicable for systemic concentrations (e.g., blood and tissues). Objective: We compared intake and systemic REPs of 1,2,3,7,8-pentachlorodibenzodioxin (PeCDD), 2,3,4,7,8-pentachlorodibenzofuran (4-PeCDF), 3,3´,4,4´,5-pentachlorobiphenyl (PCB-126), 2,3´,4,4´,5-pentachlorobiphenyl (PCB-118), and 2,3,3´,4,4´,5-hexachlorobiphenyl (PCB-156) in female C57BL/6 mice 3 days after a single oral dose. Methods: We calculated intake REPs and systemic REPs based on administered dose and liver, adipose, or plasma concentrations relative to TCDD. Hepatic cytochrome P450 1A1–associated ethoxyresorufin-O-deethylase (EROD) activity and gene expression of Cyp1a1, 1a2 and 1b1 in the liver and peripheral blood lymphocytes (PBLs) were used as biological end points. Results: We observed up to one order of magnitude difference between intake REPs and systemic REPs. Two different patterns were discerned. Compared with intake REPs, systemic REPs based on plasma or adipose levels were higher for PeCDD, 4-PeCDF, and PCB-126 but lower for the mono-ortho PCBs 118 and 156. Conclusions: Based on these mouse data, the comparison between intake REPs and systemic REPs reveals significant congener-specific differences that warrants the development of systemic TEFs to calculate toxic equivalents (TEQs) in blood and body tissues. PMID:23674508

  19. Investigation of the bioavailability of hypericin, pseudohypericin, hyperforin and the flavonoids quercetin and isorhamnetin following single and multiple oral dosing of a hypericum extract containing tablet.

    PubMed

    Schulz, Hans-Ulrich; Schürer, Michael; Bässler, Dagmar; Weiser, Dieter

    2005-01-01

    The objective of these two open phase I clinical trials was the investigation of the bioavailability of five constituents from a hypericum extract containing tablet, which are discussed as the components contributing to the antidepressant action. Each trial included 18 healthy male volunteers who received the test preparation, containing 612 mg dry extract of St John's wort (STW-3, Laif 600), either as a single oral dose or as a multiple once daily dose over a period of 14 days. Concentration/time curves were determined for hypericin, pseudohypericin, hyperforin, the flavonoid aglycone quercetin, and its methylated form isorhamnetin for 48 h after single dosing and for 24 h on day 14 at the end of 2 weeks of continuous daily dosing. After single dose intake, the key pharmacokinetic parameters were determined as follows: hypericin: area under the curve (AUC(0-infinity)) = 75.96 h x ng/ml, maximum plasma concentration (Cmax) = 3.14 ng/ml, time to reach Cmax (t(max)) = 8.1 h, and elimination half-life (t1/2) = 23.76 h; pseudohypericin: AUC(0-infinity) = 93.03 h x ng/ml, Cmax = 8.50 ng/ml, t(max) = 3.0 h, t1/2 = 25.39 h; hyperforin: AUC(0-max) = 1009.0 h x ng/ml, Cmax = 83.5 nglml, t(max) = 4.4 h, t1/2 = 19.64 h. Quercetin and isohamnetin showed two peaks of maximum plasma concentration separated by about 4 h. Quercetin: AUC(0-infinity) = 318,7 h x ng/ml, Cmax (1) = 47.7 ng/ml, t(max) (1) = 1.17 h, Cmax (2) = 43.8 ng/ml, t(max) (2) = 5.47 h, t1/2 = 4.16 h; isorhamnetin: AUC(0-infinity) = 98.0 h x ng/ml, Cmax (1) = 7.6 ng/ml, t(max) (1) = 1.53 h, Cmax (2) = 9.0 ng/ml, t(max), (2) = 6.42 h, t1/2 = 4.45 h. Under steady state conditions reached during multiple dose administration similar results were obtained. Further pharmacokinetic characteristics calculated from the obtained data were the mean residence time (MRT), the lag-time, the peak-trough fluctuation (PTF), the lowest observed plasma concentration (Cmin), and the average plasma concentration (Cav). The data

  20. Pharmacokinetic Comparison of a Single Oral Dose of Polymorph Form I versus Form V Capsules of the Antiorthopoxvirus Compound ST-246 in Human Volunteers

    PubMed Central

    Chinsangaram, Jarasvech; Honeychurch, Kady M.; Tyavanagimatt, Shanthakumar R.; Bolken, Tove' C.; Jordan, Robert; Jones, Kevin F.; Marbury, Thomas; Lichtenstein, Israel; Pickens, Margaret; Corrado, Michael; Landis, Patrick; Clarke, Jean M.; Frimm, Annie M.

    2012-01-01

    ST-246, a novel compound that inhibits egress of orthopoxvirus from mammalian cells, is being tested as a treatment for pathogenic orthopoxvirus infections in humans. This phase I, double-blind, randomized, crossover, exploratory study was conducted to compare the pharmacokinetics (PK) of a single daily 400-mg oral dose of ST-246 polymorph form I versus polymorph form V administered to fed, healthy human volunteers. Both forms appeared to be well tolerated, with no serious adverse events. The order of administration of the two forms had no effect on the results of the PK analyses. Form I and form V both exhibited comparable plasma concentration versus time profiles, but complete bioequivalence between the two forms was not found. Maximum drug concentration (Cmax) met the bioequivalence criteria, as the 90% confidence interval (CI) was 80.6 to 96.9%. However, the area under the concentration-time curve from time zero to time t (AUC0-t) and AUC0-∞ did not meet the bioequivalence criteria (CIs of 67.8 to 91.0% and 73.9 to 104.7%, respectively). The extent of absorption of form I, as defined by AUC0-∞, was 11.7% lower than that of form V. Since ST-246 form I is more thermostable than form V, form I was selected for further development and use in all future studies. PMID:22526314

  1. Randomized, Controlled Human Challenge Study of the Safety, Immunogenicity, and Protective Efficacy of a Single Dose of Peru-15, a Live Attenuated Oral Cholera Vaccine

    PubMed Central

    Cohen, Mitchell B.; Giannella, Ralph A.; Bean, Judy; Taylor, David N.; Parker, Susan; Hoeper, Amy; Wowk, Stephen; Hawkins, Jennifer; Kochi, Sims K.; Schiff, Gilbert; Killeen, Kevin P.

    2002-01-01

    Peru-15 is a live attenuated oral vaccine derived from a Vibrio cholerae O1 El Tor Inaba strain by a series of deletions and modifications, including deletion of the entire CT genetic element. Peru-15 is also a stable, motility-defective strain and is unable to recombine with homologous DNA. We wished to determine whether a single oral dose of Peru-15 was safe and immunogenic and whether it would provide significant protection against moderate and severe diarrhea in a randomized, double-blind, placebo-controlled human volunteer cholera challenge model. A total of 59 volunteers were randomly allocated to groups to receive either 2 × 108 CFU of reconstituted, lyophilized Peru-15 vaccine diluted in CeraVacx buffer or placebo (CeraVacx buffer alone). Approximately 3 months after vaccination, 36 of these volunteers were challenged with approximately 105 CFU of virulent V. cholerae O1 El Tor Inaba strain N16961, prepared from a standardized frozen inoculum. Among vaccinees, 98% showed at least a fourfold increase in vibriocidal antibody titers. After challenge, 5 (42%) of the 12 placebo recipients and none (0%) of the 24 vaccinees had moderate or severe diarrhea (≥3,000 g of diarrheal stool) (P = 0.002; protective efficacy, 100%; lower one-sided 95% confidence limit, 75%). A total of 7 (58%) of the 12 placebo recipients and 1 (4%) of the 24 vaccinees had any diarrhea (P < 0.001; protective efficacy, 93%; lower one-sided 95% confidence limit, 62%). The total number of diarrheal stools, weight of diarrheal stools, incidence of fever, and peak stool V. cholerae excretion among vaccinees were all significantly lower than in placebo recipients. Peru-15 is a well-tolerated and immunogenic oral cholera vaccine that affords protective efficacy against life-threatening cholera diarrhea in a human volunteer challenge model. This vaccine may therefore be a safe and effective tool to prevent cholera in travelers and is a strong candidate for further evaluation to prevent cholera

  2. Assessment of the effects of hepatic impairment and smoking on the pharmacokinetics of a single oral dose of the soluble guanylate cyclase stimulator riociguat (BAY 63-2521)

    PubMed Central

    Becker, Corina; Unger, Sigrun; Schmidt, Anja; Wensing, Georg; Mück, Wolfgang

    2016-01-01

    Abstract Riociguat, a soluble guanylate cyclase stimulator developed for the treatment of pulmonary hypertension, is metabolized in part by the liver. Expression of one of the metabolizing enzymes, CYP1A1, is induced by aromatic hydrocarbons in tobacco smoke. Two nonrandomized, nonblinded studies were conducted to investigate the pharmacokinetics of riociguat in individuals with mild (Child-Pugh A) or moderate (Child-Pugh B) hepatic impairment associated with liver cirrhosis compared with that in age-, weight-, and sex-matched healthy controls: study 1 included smokers and nonsmokers, and study 2 included nonsmokers only. Data from these studies were integrated for analysis. All participants (N = 64) received a single oral dose of riociguat 1.0 mg. Riociguat exposure was significantly higher in individuals with Child-Pugh B hepatic impairment than in healthy controls (ratio: 153% [90% confidence interval: 103%–228%]) but was similar in those with Child-Pugh A hepatic impairment and controls. The half-life of the riociguat metabolite M1 was prolonged in patients with Child-Pugh B or A hepatic impairment compared with that in controls by approximately 43% and 24%, respectively. Impaired hepatic function was associated with higher riociguat exposure in nonsmokers compared with the population of smokers and nonsmokers combined. Riociguat’s safety profile was similar in individuals with impaired or normal liver function. In conclusion, moderate hepatic impairment was associated with increased riociguat exposure compared with that in controls, probably as a result of reduced clearance of the metabolite M1. This suggests that dose titration of riociguat should be administered with particular care in patients with moderate hepatic impairment. PMID:27162628

  3. A Single-Dose, Single-Period Pharmacokinetic Assessment of an Extended-Release Orally Disintegrating Tablet of Methylphenidate in Children and Adolescents with Attention-Deficit/Hyperactivity Disorder

    PubMed Central

    Childress, Ann; Newcorn, Jeffrey; Stark, Jeffrey G.; McMahen, Russ; Tengler, Mark

    2016-01-01

    Abstract Objective: To determine the pharmacokinetic (PK) profile of a proprietary formulation of methylphenidate (MPH) in children and adolescents with attention-deficit/hyperactivity disorder (ADHD) in a phase 1 study. Methylphenidate extended-release orally disintegrating tablets (MPH XR-ODTs) combine two technologies in a single-tablet formulation—an extended-release profile that was designed for once-daily dosing in an ODT that does not require water or chewing for ingestion. Methods: This was a single-dose, open-label, single-period, single-treatment study, in which 32 children with ADHD who were receiving MPH in doses of 40 or 60 mg before beginning the study each received a 60-mg dose (2 × 30 mg) of MPH XR-ODT. The following plasma PK parameters of MPH were determined for participants grouped by age (6–7, 8–9, 10–12, and 13–17 years old): maximum concentration (Cmax), time to maximum concentration (Tmax), elimination half-life (T½), area under the curve from 0 hours to infinity (AUCinf), oral clearance (CL/F), and volume of distribution in the terminal phase (Vz/F). Safety and tolerability were also assessed. Results: A total of 32 participants received the study drug. For all participants, plasma concentration–time profiles of MPH exhibited a broad peak after administration of MPH XR-ODT through ∼8 hours, indicating extended release from the formulation, followed by an apparent first-order elimination phase. As age increased, MPH exposure decreased and mean estimates of CL/F increased; however, weight-normalized CL/F values were comparable across age groups. Similarly, mean estimates of Vz/F increased with age, but weight-normalization decreased differences across age groups, with the exception of the youngest age group, which had higher values. All adverse events (AEs) were mild. Conclusion: This XR-ODT formulation of MPH demonstrated weight-normalized clearance rates that were consistent across all age groups, a PK profile

  4. N,N-dimethyl-2-phenylpropan-1-amine quantification in urine: application to excretion study following single oral dietary supplement dose.

    PubMed

    Wójtowicz, Marzena; Jarek, Anna; Chajewska, Katarzyna; Kwiatkowska, Dorota

    2016-07-01

    N,N-dimethyl-2-phenylpropan-1-amine (NN-DMPPA) is a new designer stimulant prohibited in sport in-competition according to the List of Prohibited Substances and Methods published by the World Anti-Doping Agency (WADA). The first published data on the excretion study of NN-DMPPA to support the knowledge of NN-DMPPA in routine anti-doping control have been presented. The reliable gas chromatography-mass spectrometry quantitative method (GC-MS) has been validated and applied to the excretion study of NN-DMPPA. The validation parameters of the GC-MS method for determination of NN-DMPPA in human urine were the linear calibration range of 100 to 7500 ng/mL, the LOD of 13.9 ng/mL and the LOQ of 42.2 ng/mL. According to the obtained repeatability, intermediate precision, and trueness, the applied GC-MS method was precise and accurate. Urine samples from three volunteers in the excretion study were collected for 5 days after single oral administration of the supplement NOXPUMP containing NN-DMPPA. The obtained results showed the maximum concentration of NN-DMPPA (189-303 ng/mL) in urine samples at a time of 2-3 h post-administration. The NN-DMPPA concentration in urine samples was higher than 50 ng/mL until 22-23 h after the dietary supplement ingestion. This means that according to the WADA rules the use of a supplement containing NN-DMPPA may be related to a positive case when athletes took this supplement in-competition. Moreover, excretion results demonstrate also that NN-DMPPA may be detected in urine samples by the applied GC-MS method till 46 h after supplement administration. Additionally, the excretion study of β-methylphenethylamine as the second prohibited substance present in the supplement NOXPUMP has been investigated. Graphical Abstract Excretion study of new designer stimulant, N,N-dimethyl-2-phenylpropan-1-amine, and β-methylphenethylamine following single oral NOXPUMP supplement dose. PMID:27178556

  5. A Double-Blind, Placebo-Controlled Trial to Evaluate the Safety, Tolerability, and Pharmacokinetics of Single, Escalating Oral Doses of JDTic

    PubMed Central

    Buda, Jeffrey J; Carroll, F I; Kosten, Thomas R; Swearingen, Dennis; Walters, Bradford B

    2015-01-01

    Animal studies suggest that kappa opioid receptor antagonists (KORAn) potentially could treat a wide variety of addictive and depressive disorders. We assessed the KORAn JDTic for safety, tolerability, and pharmacokinetics in a double-blind, placebo-controlled, randomized trial evaluating single oral doses in healthy adult males. Predose and postdose safety assessments included orthostatic vital signs; 6-lead continuous telemetry monitoring (approximately 16 h predose to 24 h postdose); 12-lead electrocardiograms (ECGs); clinical chemistry, hematology, coagulation, and urinalysis; psychomotor functioning (using the Wayne Saccadic Fixator (WSF)); and adverse events. As a potential indicator of JDTic effects on affect, the POMS Standard instrument was administered predose and daily postdose Days 1–6. At 1 mg, 2 of the 6 JDTic (and 0/6 placebo) subjects experienced a single, asymptomatic event of multiple beats of nonsustained ventricular tachycardia (NSVT). Their events were temporally similar with respect to time postdose (and the postdose timing of an NSVT event in a monkey). These events triggered a study stopping rule. No differences were observed between the placebo and JDTic subjects with respect to clinical chemistry, hematology, coagulation, urinalysis, orthostatic vital signs, WSF, or 12-lead ECG parameters. Plasma JDTic levels were below the lower limit of quantitation (0.1 nM) in all subjects. There were no significant differences in POMS scores between the placebo and JDTic groups. Although the evidence is circumstantial, it suggests that NSVT is a potential JDTic toxicity in humans. Given the therapeutic potential of KORAn, further investigation is needed to determine whether a significant JDTic human cardiac effect indeed exists, and if so, whether it is specific to JDTic or represents a KORAn class effect. PMID:25628006

  6. The absorption, distribution, excretion, and metabolism of a single oral dose of O-ethyl O-4-nitrophenyl phenylphosphonothioate in hens

    SciTech Connect

    Abou-Donia, M.B.; Reichert, B.L.; Ashry, M.A.

    1983-08-01

    The disposition and metabolism of a single oral 10 mg/kg (LD50) of uniformly phenyl-labeled (/sup 14/C)EPN (O-ethyl O-4-nitrophenyl (/sup 14/C)phenylphosphonothioate) were studied in adult hens. The birds were protected from acute toxicity with atropine sulfate. Three treated hens were killed at each time interval (days): 0.5, 2, 4, 8, 12. Radioactivity was adsorbed from the gastrointestinal tract and distributed in all tissues. Most of the dose was excreted in the combined urinary-fecal excreta (74%). Only traces of the radioactivity (0.2%) were detected in expired CO/sub 2/. Most of the excreted radioactive materials were identified as phenylphosphonic acid (PPA), O-ethyl phenylphosphonic acid (EPPA), and O-ethyl phenylphosphonothioc acid (EPPTA). Radioactivity in tissues reached a peak of 11.8% in 12 days. The highest concentration of radioactivity was present in the liver followed by bile, kidney, adipose tissue, and muscle. EPN was the major compound identified in brain, spinal cord, sciatic nerve, kidney, and plasma. Most of the radioactivity in the liver was identified as EPPA followed by EPPTA and PPA. Kinetic studies showed that EPN disappeared exponentially from tissues. The half-life of the elimination of EPN from plasma was 16.5 days corresponding to a constant rate value of 0.04 day-1. Relative residence (RR) of EPN relative to plasma was shortest in liver and longest in adipose tissue followed by sciatic nerve and spinal cord.

  7. Pooled post hoc analysis of population pharmacokinetics of oxycodone and acetaminophen following a single oral dose of biphasic immediate-release/extended-release oxycodone/acetaminophen tablets.

    PubMed

    Franke, Ryan M; Morton, Terri; Devarakonda, Krishna

    2015-01-01

    This analysis evaluated the single-dose population pharmacokinetics (PK) of biphasic immediate-release (IR)/extended-release (ER) oxycodone (OC)/acetaminophen (APAP) 7.5/325 mg tablets administered under fasted conditions and the effects of a meal on their single-dose population PK. Data were pooled from four randomized, single-dose crossover trials enrolling healthy adult (18-55 years old) participants (three trials) and nondependent recreational users of prescription opioids (one trial) with a body weight of ≥59 kg. Participants received IR/ER OC/APAP 7.5/325 mg tablets in single doses of 7.5/325 mg (one tablet), 15/650 mg (two tablets), or 30/1,300 mg (four tablets) under fasted or fed conditions. Six variables were examined: sex, race, age, weight, height, and body mass index. Single-dose population PK was analyzed using first-order conditional estimation methods. A total of 151 participants were included in the analysis under fasted conditions, and 31 participants were included in the fed analysis. Under fasted conditions, a 10% change in body weight was accompanied by ~7.5% change in total body clearance (CL/F) and volume of distribution (V/F) of OC and APAP. Black participants had 17.3% lower CL/F and a 16.9% lower V/F of OC compared with white participants. Under fed conditions, the absorption rate constant of OC and APAP decreased significantly, although there was no effect on CL/F and V/F. Considering that the recommended dose for IR/ER OC/APAP 7.5/325 mg tablets is two tablets every 12 hours, adjustments of <50% are not clinically relevant. Dose adjustment may be necessary for large deviations from average body weight, but the small PK effects associated with race and consumption of a meal are not clinically relevant.

  8. Bioequivalence of acenocoumarol in chilean volunteers: an open, randomized, double-blind, single-dose, 2-period, and 2-sequence crossover study for 2 oral formulations.

    PubMed

    Sasso, J; Carmona, P; Quiñones, L; Ortiz, M; Tamayo, E; Varela, N; Cáceres, D; Saavedra, I

    2012-08-01

    The aim of this study was to compare the bioavailability of an oral formulation of the coumarin derivative-vitamine K antagonist acenocoumarol (Acebron™ 4 mg, Test) with the reference formulation (Neo-Sintrom™ 4 mg). We performed a single-dose, double-blind, fasting, 2-period, 2-sequence, crossover study design. Plasma concentrations of acenocoumarol were determined using a validated UPLC-MS/MS method. 24 healthy Chilean volunteers (11 male, 13 female) were enrolled and all of them completed the study. Adverse events were monitored throughout the study. The values of the pharmacokinetic parameters were (mean ± SD): AUC0-24 =1 364.38±499.26 ngxh/mL for the test and 1 328.39±429.20 ngxh/mL for the reference; AUC0-∞ =1 786.00±732.85 ngxh/mL for the test and 1 706.71±599.66 ngxh/mL for the reference; Cmax =180.69±35.11 ng/mL with a Tmax of 1.83±0.95 h for the test and 186.97±38.21 ng/mL with a Tmax of 2.19±0.83 h for the reference. Regarding half life measurements, the mean ± SD of t1/2 were 11.84±4.54 h for the test and 11.08±3.28 h for the reference. The 90% confidence intervals for the test/reference ratio using logarithmic transformed data were 97.89-100.87%, 98.62-101.99% and 98.64-102.38% for Cmax, AUC0-t(24) and AUC0-∞. There were no significant differences in pharmacokinetic parameters between groups.The results obtained in this study lead us to conclude, based on FDA criteria, that the test acenocoumarol formulation (Acebron™, 4 mg tablets) is bioequivalent to the reference product (Neo-Sintrom™, 4 mg tablets). PMID:22773430

  9. Persistent increase of blood lead level and suppression of δ-ALAD activity in northern bobwhite quail orally dosed with even a single 2-mm spent lead shot.

    PubMed

    Holladay, S D; Kerr, R; Holladay, J P; Meldrum, B; Williams, S M; Gogal, R M

    2012-10-01

    Birds that display grit ingestion behavior are potentially at risk of lead (Pb) poisoning from mistaken ingestion of spent Pb shot pellets. The majority of available studies designed to assess such risk have used unspent shot pellets rather than field-obtained spent shot, which is oxidized and otherwise changed by weathering. Available studies also often administered more or heavier shot pellets to a bird than it might be expected to ingest. The current study dosed northern bobwhite quail (Colinus virginianus) weighing 194.6 ± 23.1 g (female birds) and 199.3 ± 12.2 g (male birds) with one to three spent no. 9 Pb shot collected from a skeet range, with particular interest in the toxicity that may occur from ingestion of a single 2-mm, 50 mg shot. An 8 week post-dosing clinical observation period was employed, over which feed consumption, body weight, blood Pb levels, and a battery of blood physiological parameters were made. Weight loss occurred in the birds, including male birds dosed with one Pb pellet. Erythrocyte delta aminolevulinic acid dehydratase (δ-ALAD) levels were decreased for the duration of the study across exposures and to levels associated with injury in wild bird populations. Decreased ALAD was particularly severe in female birds dosed with one Pb pellet and was still 92 % decreased at 8 weeks after dosing. Together, these results suggest that inadvertent ingestion of a single no. 9 Pb shot pellet can adversely affect the health of northern bobwhite quail.

  10. Exposure-safety-efficacy analysis of single-agent ixazomib, an oral proteasome inhibitor, in relapsed/refractory multiple myeloma: dose selection for a phase 3 maintenance study.

    PubMed

    Gupta, Neeraj; Labotka, Richard; Liu, Guohui; Hui, Ai-Min; Venkatakrishnan, Karthik

    2016-06-01

    Background Ixazomib is the first oral, small molecule proteasome inhibitor to reach phase 3 trials. The current analysis characterized the exposure-safety and exposure-efficacy relationships of ixazomib in patients with relapsed/refractory multiple myeloma (MM) with a purpose of recommending an approach to ixazomib dosing for maintenance therapy. Methods Logistic regression was used to investigate relationships between ixazomib plasma exposure (area under the curve/day; derived from individual apparent clearance values from a published population pharmacokinetic analysis) and safety/efficacy outcomes (hematologic [grade ≥ 3 vs ≤ 2] or non-hematologic [grade ≥ 2 vs ≤ 1] adverse events [AEs], and clinical benefit [≥stable disease vs progressive disease]) using phase 1 data in relapsed/refractory MM (NCT00963820; N = 44). Results Significant relationships to ixazomib exposure were observed for five AEs (neutropenia, thrombocytopenia, rash, fatigue, and diarrhea) and clinical benefit (p < 0.05). Dose-response relationships indicated a favorable benefit/risk ratio at 3 mg and 4 mg weekly, which are below the maximum tolerated dose of 5.5 mg. At 3 mg, the model predicted that: 37 % of patients will achieve clinical benefit; incidence of grade ≥ 3 neutropenia and thrombocytopenia will be 10 % and 23 %, respectively; and incidence of grade ≥ 2 rash, fatigue, and diarrhea will be 8 %, 19 %, and 19 %, respectively. Conclusions Based on the findings, patients in the phase 3 maintenance trial will initiate ixazomib at a once-weekly dose of 3 mg, increasing to 4 mg if acceptable tolerability after 4 cycles, to provide maximum clinical benefit balanced with adequate tolerability. PMID:27039387

  11. SODIUM BICARBONATE FACILITATES LOW-DOSE ORAL TOLERANCE TO PEANUT IN MICE

    EPA Science Inventory

    Rationale: Oral tolerance specifically inhibits production of allergic IgE antibody and is therefore a potential method for suppressing food allergy. We have previously demonstrated that a single oral dose of one mg is sufficient to induce oral tolerance to egg white but not pean...

  12. Prevention of surgical site infection in lower limb skin lesion excisions with single dose oral antibiotic prophylaxis: a prospective randomised placebo-controlled double-blind trial

    PubMed Central

    Smith, Samuel C; Heal, Clare F; Buttner, Petra G

    2014-01-01

    Objectives To determine the effectiveness of a single perioperative prophylactic 2 g dose of cephalexin in preventing surgical site infection (SSI) following excision of skin lesions from the lower limb. Design Prospective double-blinded placebo-controlled trial testing for difference in infection rates. Setting Primary care in regional North Queensland, Australia. Participants 52 patients undergoing lower limb skin lesion excision. Interventions 2 g dose of cephalexin 30–60 min before excision. Main outcome measures Incidence of SSI. Results Incidence of SSI was 12.5% (95% CI 2.7% to 32.4%) in the cephalexin group compared with 35.7% (95% CI 18.6% to 55.9%) in the placebo group (p=0.064). This represented an absolute reduction of 23.21% (95% CI −0.39% to 46.82%), relative reduction of 65.00% (95% CI −12.70% to 89.13%) and number-needed-to-treat of 4.3. Conclusions Administration of a single 2 g dose of cephalexin 30–60 min before skin lesion excision from the lower limb may produce a reduction in the incidence of infection; however, this study was underpowered to statistically determine this. Trial registration number ACTRN12611000595910. PMID:25079934

  13. High dose rate brachytherapy for oral cancer

    PubMed Central

    YamazakI, Hideya; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Furukawa, Souhei; Koizumi, Masahiko; Ogawa, Kazuhiko

    2013-01-01

    Brachytherapy results in better dose distribution compared with other treatments because of steep dose reduction in the surrounding normal tissues. Excellent local control rates and acceptable side effects have been demonstrated with brachytherapy as a sole treatment modality, a postoperative method, and a method of reirradiation. Low-dose-rate (LDR) brachytherapy has been employed worldwide for its superior outcome. With the advent of technology, high-dose-rate (HDR) brachytherapy has enabled health care providers to avoid radiation exposure. This therapy has been used for treating many types of cancer such as gynecological cancer, breast cancer, and prostate cancer. However, LDR and pulsed-dose-rate interstitial brachytherapies have been mainstays for head and neck cancer. HDR brachytherapy has not become widely used in the radiotherapy community for treating head and neck cancer because of lack of experience and biological concerns. On the other hand, because HDR brachytherapy is less time-consuming, treatment can occasionally be administered on an outpatient basis. For the convenience and safety of patients and medical staff, HDR brachytherapy should be explored. To enhance the role of this therapy in treatment of head and neck lesions, we have reviewed its outcomes with oral cancer, including Phase I/II to Phase III studies, evaluating this technique in terms of safety and efficacy. In particular, our studies have shown that superficial tumors can be treated using a non-invasive mold technique on an outpatient basis without adverse reactions. The next generation of image-guided brachytherapy using HDR has been discussed. In conclusion, although concrete evidence is yet to be produced with a sophisticated study in a reproducible manner, HDR brachytherapy remains an important option for treatment of oral cancer. PMID:23179377

  14. Pharmacokinetics and Safety of FV-100, a Novel Oral Anti-Herpes Zoster Nucleoside Analogue, Administered in Single and Multiple Doses to Healthy Young Adult and Elderly Adult Volunteers▿

    PubMed Central

    Pentikis, Helen S.; Matson, Mark; Atiee, George; Boehlecke, Brian; Hutchins, Jeff T.; Patti, Joseph M.; Henson, Geoffrey W.; Morris, Amy

    2011-01-01

    FV-100 is the prodrug of the highly potent anti-varicella zoster virus bicyclic nucleoside analogue CF-1743. To characterize the pharmacokinetics and safety of oral FV-100, 3 randomized, double-blind, placebo-controlled clinical trials were conducted: (i) a single-ascending-dose study in 32 healthy subjects aged 18 to 55 years (100-, 200-, 400-, and 800-mg doses) with an evaluation of the food effect in the 400-mg group; (ii) a multiple-ascending-dose study in 48 subjects aged 18 to 55 years (100 mg once daily [QD], 200 mg QD, 400 mg QD, 400 mg twice a day, and 800 mg QD for 7 days); and (iii) a 2-part study in subjects aged 65 years and older with a single 400-mg dose in 15 subjects and a 400-mg QD dosing regimen for 7 days in 12 subjects. FV-100 was rapidly and extensively converted to CF-1743, the concentration of which remained above that required to reduce viral activity by 50% for the 24-hour dosing period. Renal excretion of CF-1743 was very low. A high-fat meal reduced exposure to CF-1743; a low-fat meal did not. Pharmacokinetic parameters for the elderly subjects were comparable to those for the younger subjects. FV-100 was well tolerated by all subjects. The pharmacokinetic and safety profiles of FV-100 support its continued investigation for the treatment of herpes zoster and prevention of postherpetic neuralgia with once-daily dosing and without dose modifications for elderly or renally impaired patients. PMID:21444712

  15. Distribution of radio-labeled N-Acetyl-L-Cysteine in Sprague-Dawley rats and its effect on glutathione metabolism following single and repeat dosing by oral gavage.

    PubMed

    Arfsten, Darryl P; Johnson, Eric W; Wilfong, Erin R; Jung, Anne E; Bobb, Andrew J

    2007-01-01

    The distribution of radio-labeled N-Acetyl-L-Cysteine (NAC) and its impact on glutathione (GSH) metabolism was studied in Sprague-Dawley rats following single and multiple dosing with NAC by oral gavage. Radioactivity associated with administration of (14)C-NAC distributed to most tissues examined within 1 hour of administration with peak radioactivity levels occurring within 1 hour to 4 hours and for a majority of the tissues examined, radioactivity remained elevated for up to 12 hours or more. Administration of a second dose of 1,200 mg/kg NAC + (14)C-NAC 4 hours after the first increased liver, kidney, skin, thymus, spleen, eye, and serum radioactivity significantly beyond levels achieved following 1 dose. Administration of a third dose of 1,200 mg/kg NAC + (14)C-NAC 4 hours after the second dose did not significantly increase tissue radioactivity further except in the skin. GSH concentrations were increased 20% in the skin and 50% in the liver after one dose of 1,200 mg/kg NAC whereas lung and kidney GSH were unaffected. Administration of a second and third dose of 1,200 mg/kg NAC at 4 hours and 8 hours after the first did not increase tissue GSH concentrations above background with the exception that skin GSH levels were elevated to levels similar to those obtained after a single dose of NAC. Glutathione-S-transferase (GST) activity was increased 150% in the kidney and 10% in the liver, decreased 60% in the skin, and had no effect on lung GST activity following a single dose of 1,200 mg/kg NAC. Administration of a second dose of 1,200 mg/kg NAC 4 hours after the first decreased skin GST activity a further 20% whereas kidney GST activity remained elevated at levels similar to those obtained after 1 dose of NAC. Administration of a third dose of NAC 4 hours after the second dose increased liver GST activity significantly as compared to background but did not affect skin, kidney, or lung GST activity. Transient decreases in glutathione reductase (GR) activity

  16. Blood phenylalanine concentrations in patients with PAH-deficient hyperphenylalaninaemia off diet without and with three different single oral doses of tetrahydrobiopterin: assessing responsiveness in a model of statistical process control.

    PubMed

    Lindner, M; Gramer, G; Garbade, S F; Burgard, P

    2009-08-01

    Tetrahydrobiopterin (BH(4)) cofactor loading is a standard procedure to differentiate defects of BH(4) metabolism from phenylalanine hydroxylase (PAH) deficiency. BH(4) responsiveness also exists in PAH-deficient patients with high residual PAH activity. Unexpectedly, single cases with presumed nil residual PAH activity have been reported to be BH(4) responsive, too. BH(4) responsiveness has been defined either by a >or=30% reduction of blood Phe concentration after a single BH(4) dose or by a decline greater than the individual circadian Phe level variation. Since both methods have methodological disadvantages, we present a model of statistical process control (SPC) to assess BH(4) responsiveness. Phe levels in 17 adult PKU patients of three phenotypic groups off diet were compared without and with three different single oral dosages of BH(4) applied in a double-blind randomized cross-over design. Results are compared for >or=30% reduction and SPC. The effect of BH(4) by >or=30% reduction was significant for groups (p < 0.01) but not for dose (p = 0.064), with no interaction of group with dose (p = 0.24). SPC revealed significant effects for group (p < 0.01) and the interaction for group with dose (p < 0.05) but not for dose alone (p = 0.87). After one or more loadings, seven patients would be judged to be BH(4) responsive either by the 30% criterion or by the SPC model, but only three by both. Results for patients with identical PAH genotype were not very consistent within (for different BH(4) doses) and between the two models. We conclude that a comparison of protein loadings without and with BH(4) combined with a standardized procedure for data analysis and decision would increase the reliability of diagnostic results. PMID:19513811

  17. Single dose dipyrone for acute postoperative pain

    PubMed Central

    Derry, Sheena; Faura, Clara; Edwards, Jayne; McQuay, Henry J; Moore, R Andrew

    2014-01-01

    Background Dipyrone (metamizole) is a non-steroidal anti-inflammatory drug used in some countries to treat pain (postoperative, colic, cancer, and migraine); it is banned in others because of an association with life-threatening blood agranulocytosis. This review updates a 2001 Cochrane review, and no relevant new studies were identified, but additional outcomes were sought. Objectives To assess the efficacy and adverse events of single dose dipyrone in acute postoperative pain. Search methods The earlier review searched CENTRAL, MEDLINE, EMBASE, LILACS and the Oxford Pain Relief Database to December 1999. For the update we searched CENTRAL, MEDLINE,EMBASE and LILACS to February 2010. Selection criteria Single dose, randomised, double-blind, placebo or active controlled trials of dipyrone for relief of established moderate to severe postoperative pain in adults. We included oral, rectal, intramuscular or intravenous administration of study drugs. Data collection and analysis Studies were assessed for methodological quality and data extracted by two review authors independently. Summed total pain relief over six hours (TOTPAR) was used to calculate the number of participants achieving at least 50% pain relief. Derived results were used to calculate, with 95% confidence intervals, relative benefit compared to placebo, and the number needed to treat (NNT) for one participant to experience at least 50% pain relief over six hours. Use and time to use of rescue medication were additional measures of efficacy. Information on adverse events and withdrawals was collected. Main results Fifteen studies tested mainly 500 mg oral dipyrone (173 participants), 2.5 g intravenous dipyrone (101), 2.5 g intramuscular dipyrone (99); fewer than 60 participants received any other dose. All studies used active controls (ibuprofen, paracetamol, aspirin, flurbiprofen, ketoprofen, dexketoprofen, ketorolac, pethidine, tramadol, suprofen); eight used placebo controls. Over 70% of participants

  18. Efficacy and safety of premedication with single dose of oral pregabalin in children with dental anxiety: A randomized double-blind placebo-controlled crossover clinical trial

    PubMed Central

    Eskandarian, Tahereh; Eftekharian, Hamidreza; Soleymanzade, Rojin

    2015-01-01

    Background: Dental anxiety is a relatively frequent problem that can lead to more serious problems such as a child entering a vicious cycle as he/she becomes reluctant to accept the required dental treatments. The aim of this randomized double-blind clinical trial study was to evaluate the anxiolytic and sedative effect of pregabalin in children. Materials and Methods: Twenty-five children were randomized to a double-blind placebo-controlled crossover clinical trial. Two visits were scheduled for each patient. At the first visit, 75 mg pregabalin or placebo was given randomly, and the alternative was administered at the next visit. Anxiolytic and sedative effects were measured using the visual analogue scale. The child's behavior was rated with the Frankl behavioral rating scale and the sedation level during the dental procedure was scored using the Ramsay sedation scale. The unpaired, two-tailed Student's t-test was used to compare the mean changes of visual analog scale (VAS) for anxiety in the pregabalin group with that of the placebo group. A repeated measures MANOVA model was used to detect differences in sedation level in the pregabalin and placebo groups regarding the interaction of 3-time measurements; sub-group analysis was performed using Student's t-test. The Mann–Whitney U-test was used to analyze the nonparametric data of the Frankl and Ramsay scales. A P < 0.05 was considered significant. Results: The reduction of the VAS-anxiety score from 2 h post-dose was statistically significant in the pregabalin group. From 2 h to 4 h post-dose, the VAS-sedation score increased significantly in the pregabalin group. The child's behavior rating was not significantly different between the groups. The number of “successful” treatment visits was higher in the pregabalin group compared to the placebo group. Conclusion: Significant anxiolytic and sedative effects can be anticipated 2 h after oral administration of pregabalin without serious side effects. PMID

  19. A Single Dose of Oral BCG Moreau Fails to Boost Systemic IFN-γ Responses to Tuberculin in Children in the Rural Tropics: Evidence for a Barrier to Mucosal Immunization

    PubMed Central

    Vaca, Maritza; Moncayo, Ana-Lucia; Cosgrove, Catherine A.; Chico, Martha E.; Castello-Branco, Luiz R.; Lewis, David J.; Cooper, Philip J.

    2012-01-01

    Immune responses to oral vaccines are impaired in populations living in conditions of poverty in developing countries, and there is evidence that concurrent geohelminth infections may contribute to this effect. We vaccinated 48 children living in rural communities in Ecuador with a single oral dose of 100 mg of BCG Moreau RDJ and measured the frequencies of tuberculin-stimulated peripheral blood mononuclear cells expressing IFN-γ before and after vaccination. Vaccinated children had active ascariasis (n = 20) or had been infected but received short- (n = 13) or long-term (n = 15) repeated treatments with albendazole prior to vaccination to treat ascariasis. All children had a BCG scar from neonatal vaccination. There was no evidence of a boosting of postvaccination IFN-γ responses in any of the 3 study groups. Our data provide support for the presence of a barrier to oral vaccination among children from the rural tropics that appeared to be independent of concurrent ascariasis. PMID:22287972

  20. Comparative bioavailability and pharmacokinetics of two oral formulations of flurbiprofen: a single-dose, randomized, open-label, two-period, crossover study in Pakistani subjects.

    PubMed

    Qayyum, Aisha; Najmi, Muzammil Hasan; Abbas, Mateen

    2013-11-01

    Comparative bioavailability studies are conducted to establish the bioequivalence of generic formulation with that of branded reference formulation, providing confidence to clinicians to use these products interchangeably. This study was carried out to compare a locally manufactured formulation of flurbiprofen with that of a branded product. Twenty two healthy male adults received a single dose of flurbiprofen (100mg) either generic or branded product according to randomization scheme on each of 2 periods. Blood samples were collected and plasma flurbiprofen concentration was determined by a validated HPLC method. Pharmacokinetic parameters like AUC(0-t), AUC(0-oo), Cmax, Tmax, t½, Vd and clearance were determined. The 90% CI for the ratio of geometric means of test to reference product's pharmacokinetic variables was calculated. Pharmacokinetic parameters for two formulations were comparable. Ratio of means of AUC(0-24), AUC(0-oo) and Cmax for test to reference products and 90% CI for these ratios were within the acceptable range. The p-values calculated by TOST were much less than the specified value (p-0.05). ANOVA gave p-values which were more than the specified value (p-0.05) for sequence, subject, period and formulation. Test formulation of flurbiprofen (tablet Flurso) was found to meet the criteria for bioequivalence to branded product (tablet Ansaid) based on pharmacokinetic parameters.

  1. Determination of designer doping agent--2-ethylamino-1-phenylbutane--in dietary supplements and excretion study following single oral supplement dose.

    PubMed

    Wójtowicz, Marzena; Jarek, Anna; Chajewska, Katarzyna; Turek-Lepa, Ewa; Kwiatkowska, Dorota

    2015-11-10

    The quantitative analysis of a new designer doping agent, 2-ethylamino-1-phenylbutane (EAPB) and its metabolite, 2-amino-1-phenylbutane (APB) in urine samples, and the determination of EAPB in dietary supplement samples, have been presented. The main purpose of the present study was to develop simple and reliable gas chromatography-mass spectrometry method (GC-MS) for excretion study following a single oral administration of dietary supplements containing EAPB. Three analytical methods for the determination of EAPB in urine and supplement samples, and APB in urine samples using the GC-MS system, have been validated. The method of the determination of EAPB in supplement samples was applied to analyze seventeen dietary supplements, CRAZE and DETONATE. Two other methods were used to determine the urinary excretion profile of EAPB and APB in the case of three healthy volunteers and, on further investigation, it was applied to the anti-doping control in sport. Quantification was obtained on the basis of the ions at m/z 86, 58 and 169, monitored for EAPB, APB and diphenylamine (used as an internal standard), respectively. The limits of detection and quantification were 2.4 and 7.3μg/g for EAPB in the case of supplement analysis, 2.9 and 8.8ng/mL for EAPB in the case of urine analysis, and 3.2 and 9.7ng/mL for APB. The other validation parameters as linearity, precision and trueness have been also investigated with the acceptable results. The extraction yield of all presented methods was above 69%. EAPB was detected in fourteen analyzed supplements (not included EAPB in their labels) and its content varied between 1.8 and 16.1mg/g. Following oral administration of three supplements with EAPB to one male and two female volunteers, the parent compound of EAPB and its metabolite were monitored and the excretion parameters as the maximum concentration of the analyte in urine (2.2-4.2μg/mL for EAPB; 1.1-5.1μg/mL for APB) and the time for the maximum height of the excretion

  2. Malaria-Infected Mice Live Until At Least Day 30 After A New Artemisinin-Derived Thioacetal Thiocarbonate Combined with Mefloquine Are Administered Together In A Single, Low, Oral Dose

    PubMed Central

    Jacobine, Alexander M.; Mazzone, Jennifer R.; Slack, Rachel D.; Tripathi, Abhai K.; Sullivan, David J.; Posner, Gary H.

    2012-01-01

    In only three steps and in 21–67% overall yields from the natural trioxane artemisinin, a series of 21 new trioxane C-10 thioacetals was prepared. Upon receiving a single oral dose of only 6 mg/kg of the monomeric trioxane 12c combined with 18 mg/kg of mefloquine hydrochloride, Plasmodium berghei-infected mice survived on average 29.8 days after infection. Two of the four mice in this group had no parasites detectable in their blood on day 30 after infection and they behaved normally and appeared healthy. One of the mice had 11% blood parasitemia on day 30, and one mouse in this group died on day 29. Of high medicinal importance, the efficacy of this ACT chemotherapy is much better than (almost double) the efficacy under the same conditions using as a positive control the popular trioxane drug artemether plus mefloquine hydrochloride (average survival time of only 16.5 days). PMID:22891714

  3. Investigation of pharmacokinetic data of hypericin, pseudohypericin, hyperforin and the flavonoids quercetin and isorhamnetin revealed from single and multiple oral dose studies with a hypericum extract containing tablet in healthy male volunteers.

    PubMed

    Schulz, Hans-Ulrich; Schürer, Michael; Bässler, Dagmar; Weiser, Dieter

    2005-01-01

    Hypericins, hyperforin and flavonoids are discussed as the main components contributing to the antidepressant action of St. John's wort (Hypericum perforatum). Therefore, the objective of the two open phase I clinical trials was to obtain pharmacokinetic data of these constituents from a hypericum extract containing tablet: hypericin, pseudohypericin, hyperforin, the flavonoid aglycone quercetin, and its methylated form isorhamnetin. Each trial included 18 healthy male volunteers who received the test preparation, containing 900 mg dry extract of St John's wort (STW 3-VI, Laif 900), either as a single oral dose or as a multiple once daily dose over a period of 14 days. Concentration/time curves were determined for the five constituents, for 48 h after single dosing and for 24 h on day 14 at the end of 2 weeks of continuous daily dosing. After single dose intake, the key pharmacokinetic parameters were determined as follows: Hypericin: Area under the curve (AUC(0-infinity)) = 78.33 h x ng/ml, maximum plasma concentration (Cmax) = 3.8 ng/ml, time to reach Cmax (tmax) = 7.9 h, and elimination half-life (t1/2) = 18.71 h; pseudohypericin: AUC(0-infinity) = 97.28 h x ng/ml, Cmax = 10.2 ng/ml, tmax = 2.7 h, t1/2 = 17.19 h; hyperforin: AUC(0-infinity) = 1550.4 h x ng/ml, Cmax = 122.0 ng/ml, tmax = 4.5 h, t1/2 = 17.47 h. Quercetin and isorhamnetin showed two peaks of maximum plasma concentration separated by about 3-3.5 h. Quercetin: AUC(0-infinity) = 417.38 h x ng/ml, Cmax (1) = 89.5 ng/ml, tmax (1) = 1.0 h, Cma (2) = 79.1 ng/ml, tmax (2) = 4.4 h, t1/2 = 2.6 h; isorhamnetin: AUC(0-infinity) = 155.72 h x ng/ml, Cmax (1) = 12.5 ng/ml, tmax (1) = 1.4 h, Cmax (2) = 14.6 ng/ml, tmax (2) = 4.5 h, t1/2 = 5.61 h. Under steady state conditions reached during multiple dose administration similar results were obtained. Further pharmacokinetic characteristics calculated from the obtained data were the mean residence time (MRT), the lag-time, the peak-trough fluctuation (PTF), the

  4. Di-n-butyl Phthalate (DNBP) and Diisobutyl Phthalate (DiBP) Metabolism in a Human Volunteer after Single Oral Doses [Journal Article

    EPA Science Inventory

    An individual (male, 36 years, 87 kg) ingested two separate doses of di-n-butyl phthalate (DnBP) and diisobutyl phthalate (DiBP) at a rate of ~60 µg/kg. Key monoester and oxidized metabolites were identified and quantified in urine continuously collected until 48 hours post dos...

  5. Pharmacokinetic profile of rizatriptan 10-mg tablet and 10-mg orally disintegrating tablet administered with or without water in healthy subjects: an open-label, randomized, single-dose, 3-period crossover study.

    PubMed

    Swan, Suzanne K; Alcorn, Harry; Rodgers, Anthony; Hustad, Carolyn M; Ramsey, Karen E; Woll, Susan; Skobieranda, Franck

    2006-02-01

    This open-label, 3-period crossover study compared the plasma concentration profiles of rizatriptan tablet, orally disintegrating tablet with water (ODTc), and ODT without water (ODTs) in 24 healthy volunteers aged 18 to 45 years. At each period, subjects received a single dose of either 10-mg rizatriptan tablet, 10-mg rizatriptan ODTs, or 10-mg rizatriptan ODTc. The authors hypothesized that ODTc has a greater geometric mean AUC(0-2h) than ODTs and that ODTc has a greater geometric mean AUC(0-1h) than tablet. A secondary end point was to compare the time of occurrence of the maximum rizatriptan plasma concentration (t(max)) of each dosing method. ODTc had a statistically significantly greater geometric mean AUC(0-2h) compared with ODTs (33.84 h x ng/mL vs 18.83 h x ng/mL; P < .001). ODTc had a slightly, but not statistically significantly, greater geometric mean AUC(0-1h) compared with rizatriptan tablet (17.07 h x ng/mL vs 13.32 h x ng/mL). The median t(max) was 0.67 hours for ODTc and tablet and 1.33 hours for ODTs. ODTc showed a slightly, but not significantly, faster rate of absorption compared with tablet. ODTs with water had a faster rate of absorption than ODTc. Future studies are needed to determine whether this pharmacokinetic difference produces differential efficacy in a clinical setting. PMID:16432269

  6. Developmental toxicity of clarified slurry oil, syntower bottoms, and distillate aromatic extract administered as a single oral dose to pregnant rats

    SciTech Connect

    Feuston, M.H.; Mackerer, C.R.

    1996-09-01

    Clarified slurry oil (CSO), syntower bottoms (STB), and distillate aromatic extract (DAE) are refinery streams produced by processing crude oil. Available data indicate that some refinery streams are developmentally toxic by the dermal route of exposure. However, there is no conclusive evidence for their being teratogenic. The present studies were designed to further explore the suspected teratogenic potency of refinery streams while at the same time limiting embryolethality. In general, evidence of maternal toxicity (i.e., decreased body weight gain, decreased thymus weight) was observed at doses greater than or equal to 500 mg/kg. For each refinery stream tested, the incidence of resorption was greatest on GD 11. A common pattern of fetal malformations was observed for all of the refinery streams tested and included cleft palate, diaphragmatic hernia, and paw and tail defects. The incidence and type of malformation observed were influenced by the gestation day of exposure. The incidence and type of malformation observed were influenced by the gestation day of exposure. The incidences of external and skeletal malformations were greatest on GD 11 and 12 for fetuses exposed to CSO; on GD 13 and 14, the incidence of malformation was comparable for CSO- and STB-exposed fetuses. The incidence of visceral anomalies was greatest on GD 11-13 for fetuses exposed to CSO and STB; on Gestation D 14, the incidence was comparable for each of the refinery streams tested. In general, the ability to produce adverse effects on development was greatest for CSO and least for DAE. Effects produced by STB were comparable to or less severe than those observed for CSO. 24 refs., 11 tabs.

  7. Comparative oral dose toxicokinetics of sodium selenite and selenomethionine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The toxicokinetics of selenium (Se) absorption, distribution, and elimination were determined in serum and whole blood of lambs that were orally dosed with various doses of Se as sodium selenite (inorganic Se) or selenomethionine (organic Se). Thirty-two lambs were randomly assigned to eight treatm...

  8. [Sudden death following a single oral administration of haloperidol].

    PubMed

    Remijnse, P L; Eeckhout, A M; van Guldener, C

    2002-04-20

    A 39-year-old man was admitted with myasthenia, alcoholic hepatitis and electrolyte abnormalities due to an inadequate nutritional state. On admission the ECG showed a prolonged QTc interval (0.46 s). The patient was treated with intravenous fluid and supplementary vitamins and minerals. On the third day of admission the patient developed a delirium, partly due to alcohol withdrawal, and was therefore treated with oxazepam 50 mg 3 times daily and a single dose of haloperidol 5 mg. One hour after ingesting haloperidol, the patient suddenly succumbed and resuscitation was not successful. The autopsy revealed a cardiomyopathy but no explanation for the sudden death. Due to the temporal relationship between the ingestion of haloperidol and this sudden death, we assume that haloperidol induced a fatal arrhythmia in the presence of a preexisting prolonged repolarisation time. To the best of our knowledge, sudden death after a single oral therapeutic dose of haloperidol has not previously been described. PMID:11998355

  9. A Single-Dose Bioequivalence and Food Effect Study With Aprepitant and Fosaprepitant Dimeglumine in Healthy Young Adult Subjects.

    PubMed

    Shadle, Craig R; Murphy, M Gail; Liu, Yang; Ho, Maureen; Tatosian, Daniel; Li, Susie Xiujiang; Blum, Robert A

    2012-07-01

    Fosaprepitant dimeglumine, a lyophilized prodrug, is rapidly converted to aprepitant, a substance P/neurokinin 1 (NK1 ) receptor antagonist. Intravenous (IV) fosaprepitant and oral aprepitant are used in combination with other antiemetics to prevent chemotherapy-induced nausea and vomiting. This randomized, phase 1 study was designed to assess the aprepitant area under the curve (AUC0-∞ ) equivalence of a single, oral 165-mg or 185-mg dose of aprepitant to a single 150-mg fosaprepitant IV dose infused over 20 minutes, and to evaluate the effect of food on the bioavailability of the oral 165-mg and 185-mg aprepitant doses. Plasma samples were analyzed for aprepitant, and linear mixed-effects models were applied to natural log-transformed aprepitant AUC data. A 2 one-sided tests procedure was used to evaluate bioequivalence; the adjusted P values for the AUC0-∞ of both oral doses versus the IV dose were < .05, supporting the hypothesis that each single, oral dose of aprepitant is equivalent to the AUC0-∞ of a single IV infusion of fosaprepitant. Food effect results suggest that dose adjustment would not be necessary with a single oral dose of aprepitant. Single-dose administration of oral 165 mg and 185 mg aprepitant and IV 150 mg fosaprepitant was generally well tolerated. PMID:27121336

  10. Multiple dose pharmacokinetics of oral artemisinin and comparison of its efficacy with that of oral artesunate in falciparum malaria patients.

    PubMed

    Hassan Alin, M; Ashton, M; Kihamia, C M; Mtey, G J; Björkman, A

    1996-01-01

    The study compared the clinical efficacy and safety of oral artemisinin and oral artesunate as well as artemisinin pharmacokinetics during and after resolution of falciparum malaria. Forty adults with symptomatic falciparum malaria were allocated at random to treatment with either oral artemisinin (500 mg single dose on day 1 followed by 250 mg twice daily for 4 d and then another 500 mg single dose on day 6) or with oral artesunate (100 mg single dose on day 1 followed by 50 mg twice daily for 5 d). Patients were admitted to hospital at the Kibaha Designated District Hospital, Kibaha, Tanzania for the duration of treatment. The patients were seen once weekly for 3 more weeks. The time to parasite clearance (PCT) after oral artesunate (26.4 +/- 3.6 h) was shorter (P = 0.002) than after artemisinin (31 +/- 3.6 h). The fever subsidence time (FST) after oral artesunate (18.9 +/- 4.0 h) was also shorter (P = 0.04) than after artemisinin (21.8 +/- 4.6 h). Parasites were detected in 4 (20%) and 7 (35%) patients after completing treatment with artesunate and artemisinin respectively. In these patients the parasitaemia reappeared at the 3rd or 4th week of follow-up. Standard haematology, blood biochemistry and urinalysis, performed before drug intake and again on days 6 and 14, were normal. No clinical abnormality was observed during the study period. Artemisinin plasma concentrations, determined by high performance liquid chromatography with post-column derivatization and detection by ultraviolet light, were followed up to 8 h after drug administration on days 1 and 6. Artemisinin absorption was rapid, the maximum plasma concentrations (Cmax) being attained at about 3 h. Artemisinin areas under the plasma concentration-time curve (AUC) and the Cmax values were about 6 times higher after the first dose on day 1 than on day 6. This decrease in artemisinin plasma concentration is suggestive of an increase in metabolic capacity due to pronounced autoinduction.

  11. Treating acne with oral contraceptives: use of lower doses.

    PubMed

    Huber, Johannes; Walch, Katharina

    2006-01-01

    Oral contraceptives (OCs) have been shown to effectively treat acne. Clinical trials of various doses of ethinyl estradiol (EE) combined with progestins such as levonorgestrel, desogestrel, norgestimate, gestodene, cyproterone acetate and drospirenone in monophasic, triphasic and combiphasic formulations used to treat acne in women are reviewed here. Open-label and comparative studies beginning in the 1980s were the first to demonstrate objective and subjective reductions in the incidence of acne, severity of existing acne and seborrhea. Placebo-controlled trials have corroborated these findings with a trend toward effective acne treatment with declining doses of EE. Significant reductions in total, inflammatory and noninflammatory lesions compared with placebo have been demonstrated with an OC containing the low dose of 20 microg of EE. Collectively, these findings support the use of low-dose OCs for the treatment of acne. PMID:16371290

  12. Derivation of a chronic oral reference dose for cobalt.

    PubMed

    Finley, Brent L; Monnot, Andrew D; Paustenbach, Dennis J; Gaffney, Shannon H

    2012-12-01

    Cobalt (Co) is an essential element in humans as a component of vitamin B12. However, at high levels Co exposure has been shown to have detrimental effects. This study was designed to identify a chronic oral reference dose (RfD) for Co. Currently available data indicate that non-cancer health effects associated with Co exposure may include hematological, neurological, immunological, reproductive, cardiovascular, and endocrine responses. This analysis employs the standard US EPA risk assessment methodology for establishing a chronic RfD. In this analysis, the Jaimet and Thode (1955) 10-week, multiple dose human study of thyroid effects (decreased iodine uptake) in children was determined to be the most robust and sensitive study for identifying a potential point of departure dose (POD). A dose of 0.9 mgCo/kg-day was chosen as the POD. Consistent with the US EPA's previous derivation of the perchlorate RfD, which is also based on decreased iodine uptake in humans, we considered several uncertainly factors (UFs), and determined that a factor of 10 for human variability was appropriate, as well as a factor of three for database adequacy. Applying an aggregate uncertainty factor of 30 to the POD yields a chronic oral RfD of 0.03 mg/kg-day. We believe this value would be protective of non-cancer health effects in the general population for a lifetime of daily exposure to Co.

  13. Guaifenesin Pharmacokinetics Following Single‐Dose Oral Administration in Children Aged 2 to 17 Years

    PubMed Central

    Thompson, Gary A.; Solomon, Gail; Albrecht, Helmut H.; Reitberg, Donald P.

    2016-01-01

    Abstract This study characterized guaifenesin pharmacokinetics in children aged 2 to 17 years (n = 40) who received a single oral dose of guaifenesin (age‐based doses of 100‐400 mg) 2 hours after breakfast. Plasma samples were obtained before and for 8 hours after dosing and analyzed for guaifenesin using liquid chromatography‐tandem mass spectrometry. Pharmacokinetic parameters were estimated using noncompartmental methods, relationships with age were assessed using linear regression, and dose proportionality was assessed on 95% confidence intervals. Based on the upper dose recommended in the monograph (for both children and adolescents), area under the curve from time zero to infinity and maximum plasma concentration both increased with age. However, when comparing the upper dose for children aged 2 to 11 years with the lower dose for adolescents aged 12 to 17 years, similar systemic exposure was observed. As expected due to increasing body size, oral clearance (CLo) and terminal volume of distribution (Vz/F) increased with age. Due to a larger increase in Vz/F than CLo, an increase in terminal exponential half‐life was also observed. Allometric scaling indicated no maturation‐related changes in CLo and Vz/F. PMID:26632082

  14. Single dose regorafenib-induced hypertensive crisis.

    PubMed

    Yilmaz, B; Kemal, Y; Teker, F; Kut, E; Demirag, G; Yucel, I

    2014-06-01

    Gastrointestinal stromal tumors (GISTs) are uncommon tumors of the gastrointestinal (GI) tract. Regorafenib is a new multikinase inhibitor and is approved for the treatment of GISTs in patients who develop resistance to imatinib and sunitinib. The most common drug-related adverse events with regorafenib are hypertension, hand-foot skin reactions, and diarrhea. Grade IV hypertensive side effect has never been reported after a single dose. In this report, we present a case of Grade IV hypertensive side effect (hypertensive crisis and seizure) after a single dose of regorafenib. A 54-year-old male normotensive GIST patient was admitted to the emergency department with seizure and encephalopathy after the first dosage of regorafenib. His blood pressure was 240/140 mmHg upon admission. After intensive treatment with nitrate and nitroprusside, his blood pressure returned to normal levels in five days. Regorafenib was discontinued, and he did not experience hypertension again. This paper reports the first case of Grade IV hypertension after the first dosage of regorafenib. We can suggest that hypertension is an idiosyncratic side effect unrelated to the dosage.

  15. A comparative study on the anti-inflammatory effects of single oral doses of naproxen and its hydrogen sulfide (H2S)-releasing derivative ATB-346 in rats with carrageenan-induced synovitis

    PubMed Central

    2013-01-01

    Background Non-steroidal antiinflammatory drugs (NSAIDs) are the most commonly prescribed agents for arthritic patients, although gastric effects limit their long-term use. Considering the reported gastric safety of hydrogen sulfide (H2S)-releasing NSAIDs, in addition to the anti-inflammatory effects of H2S administration to rats with synovitis, we decided to evaluate the effects of the H2S-releasing naproxen derivative ATB-346 in this animal model. Methods Male Wistar rats were anesthetized with inhalatory halothane and pre-treated with equimolar oral doses of either naproxen (0.3, 1, 3 or 10 mg/kg) or ATB-346 (0.48, 1.6, 4.8, or 16 mg/kg) 30 min before the i.art. injection of 7.5 mg of carrageenan (CGN) into the right knee joint cavity. Joint swelling and pain score were assessed after 1, 3 and 5 h, and tactile allodynia after 2 and 4 h. After the last measurement, the joint cavity lavages were performed for counting of the recruited leukocytes. The drugs (at the highest doses) were also tested for their gastric effects by evaluating macroscopical damage score and neutrophil recruitment (measured as myeloperoxidase – MPO activity) in the stomachs 5 h after administration of the drugs. In addition, the serum naproxen pharmacokinetic profiles of both compounds, administered at the highest equimolar doses, were obtained during the first 6 h after dosing. Results At the two highest tested doses, both naproxen and ATB-346 reduced edema and pain score (measured 3 and 5 h after CGN; P < 0.001). Tactile allodynia was similarly inhibited by ~45% 4 h after CGN by both naproxen (at 1, 3 and 10 mg/kg) and ATB-346 (at 1.6 and 4.8 mg/kg; P < 0.001), as well as leukocyte infiltration. Naproxen (but not ATB-346) induced significant gastric damage and, despite the increased gastric MPO activity by ~130% in the naproxen-, but not in the ATB-346-treated rats, this effect was of no statistical significance. Conclusion The presence of a H2S-releasing moiety in

  16. Brachytherapy for early oral tongue cancer: low dose rate to high dose rate.

    PubMed

    Yamazaki, Hideya; Inoue, Takehiro; Yoshida, Ken; Yoshioka, Yasuo; Furukawa, Souhei; Kakimoto, Naoya; Shimizutani, Kimishige; Inoue, Toshihiko

    2003-03-01

    To examine the compatibility of low dose rate (LDR) with high dose rate (HDR) brachytherapy, we reviewed 399 patients with early oral tongue cancer (T1-2N0M0) treated solely by brachytherapy at Osaka University Hospital between 1967 and 1999. For patients in the LDR group (n = 341), the treatment sources consisted of Ir-192 pin for 227 patients (1973-1996; irradiated dose, 61-85 Gy; median, 70 Gy), Ra-226 needle for 113 patients (1967-1986; 55-93 Gy; median, 70 Gy). Ra-226 and Ir-192 were combined for one patient. Ir-192 HDR (microSelectron-HDR) was used for 58 patients in the HDR group (1991-present; 48-60 Gy; median, 60 Gy). LDR implantations were performed via oral and HDR via a submental/submandibular approach. The dose rates at the reference point for the LDR group were 0.30 to 0.8 Gy/h, and for the HDR group 1.0 to 3.4 Gy/min. The patients in the HDR group received a total dose of 48-60 Gy (8-10 fractions) during one week. Two fractions were administered per day (at least a 6-h interval). The 3- and 5-year local control rates for patients in the LDR group were 85% and 80%, respectively, and those in the HDR group were both 84%. HDR brachytherapy showed the same lymph-node control rate as did LDR brachytherapy (67% at 5 years). HDR brachytherapy achieved the same locoregional result as did LDR brachytherapy. A converting factor of 0.86 is applicable for HDR in the treatment of early oral tongue cancer.

  17. Hepatotoxicity of High Oral Dose (-)-Epigallocatechin-3-Gallate in Mice

    PubMed Central

    Lambert, Joshua D.; Kennett, Mary J.; Sang, Shengmin; Reuhl, Kenneth R.; Ju, Jihyeung; Yang, Chung S.

    2009-01-01

    The tea polyphenol (-)-epigallocatechin-3-gallate (EGCG) has been studied for chronic disease preventive effects, and is marketed as part of many dietary supplements. However, case reports have associated the use of green tea-based supplements with liver toxicity. We studied the hepatotoxic effects of high dose EGCG in male CF-1 mice. A single dose of EGCG (1500 mg/kg, i.g.) increased plasma alanine aminotransferase (ALT) by 138-fold and reduced survival by 85%. Once-daily dosing with EGCG increased hepatotoxic response. Plasma ALT levels were increased 184-fold following two once-daily doses of 750 mg/kg, i.g. EGCG. Moderate to severe hepatic necrosis was observed following treatment with EGCG. EGCG hepatotoxicity was associated with oxidative stress including increased hepatic lipid peroxidation (5-fold increase), plasma 8-isoprostane (9.5-fold increase) and increased hepatic metallothionein and γ-histone 2AX protein expression. EGCG also increased plasma interleukin-6 and monocyte chemoattractant protein 1. Our results indicate that higher bolus doses of EGCG are hepatotoxic to mice. Further studies on the dose-dependent hepatotoxic effects of EGCG and the underlying mechanisms are important given the increasing use of green tea dietary supplements, which may deliver much higher plasma and tissue concentrations of EGCG than tea beverages. PMID:19883714

  18. Thalidomide is distributed into human semen after oral dosing.

    PubMed

    Teo, S K; Harden, J L; Burke, A B; Noormohamed, F H; Youle, M; Johnson, M A; Peters, B S; Stirling, D I; Thomas, S D

    2001-10-01

    As part of a double-blind placebo-controlled study of the effect of thalidomide on body weight and the viral load of human immunodeficiency virus-seropositive patients, plasma and semen samples were analyzed for the presence of thalidomide. Patients were orally dosed with 100 mg of thalidomide/day for 8 weeks. Blood samples were obtained at baseline and weeks 4, 8, and 12, and semen was obtained at baseline and weeks 4 and 8. Samples were extracted with solid-phase cartridges and analyzed by liquid chromatography/tandem mass spectrometry using atmospheric pressure chemical ionization in the negative ion mode. Two of four patients taking thalidomide were able to provide semen samples. Both had detectable levels of thalidomide in their plasma (10-350 ng/ml) and semen (10-250 ng/g) at weeks 4 and 8. There was an apparent correlation between plasma and semen levels. Semen levels could be significantly greater for therapeutic doses of more than 100 mg/day. Since the threshold dose for birth defects and thalidomide exposure is not known, male patients are advised to use barrier contraception.

  19. Single- and Multiple-Dose Pharmacokinetics and Absolute Bioavailability of Tedizolid

    PubMed Central

    Flanagan, Shawn; Fang, Edward; Muñoz, Kelly A; Minassian, Sonia L; Prokocimer, Philippe G

    2014-01-01

    Objectives Tedizolid phosphate is a novel antibacterial under investigation for the treatment of gram-positive infections. This study was conducted to assess the pharmacokinetics, safety, and tolerability of intravenous tedizolid phosphate as well as the oral bioavailability of tedizolid phosphate. Design Double-blind, single-ascending dose, multiple-dose pharmacokinetics study, as well as tolerability and open-label crossover studies. Setting Single center in the United States (Covance Clinical Research Unit, Madison, WI) between September 2009 and January 2010. Participants Ninety healthy volunteers. Intervention Single intravenous (IV) doses of tedizolid phosphate 50 mg (lead-in) and 100–400 mg. Single oral and IV dose of tedizolid phosphate 200 mg in crossover fashion. Multiple IV doses of tedizolid phosphate 200 and 300 mg for up to 7 days. Measurements and Main Results A dose-dependent increase was observed in the maximum plasma concentration (1.2–5.1 μg/ml) and the area under the concentration-time curve (17.4–58.7 μg × hr/ml) of tedizolid (the microbiologically active moiety of tedizolid phosphate) after single IV doses of tedizolid phosphate 100–400 mg. Administration of IV tedizolid phosphate 200 mg once/day for 7 days resulted in minimal (28%) tedizolid accumulation. The absolute oral bioavailability of tedizolid after a single 200-mg dose of tedizolid phosphate was 91%; pharmacokinetic parameters of tedizolid were similar with oral and IV administration. Treatment-related adverse events occurred in 41% of subjects. Most adverse events were related to infusion site and became more frequent with multiple dosing. In an additional 3-day tolerability study, IV tedizolid phosphate 200 mg and placebo were similarly tolerated, based on visual infusion phlebitis scores. Conclusion These results from a population of healthy volunteers support once/day dosing of tedizolid phosphate 200 mg with both the oral and IV formulations, without the

  20. Pharmacokinetics of temafloxacin in humans after multiple oral doses.

    PubMed Central

    Granneman, G R; Carpentier, P; Morrison, P J; Pernet, A G

    1992-01-01

    The multiple-dose pharmacokinetics and tolerance of temafloxacin, a new fluoroquinolone antibacterial agent, were evaluated in healthy volunteers. Temafloxacin was found to be well tolerated when administered orally every 12 h for 7 days at doses of 100, 200, 300, 400, 600, and 800 mg. Steady-state maximum and minimum concentrations in plasma were proportional to dose, averaging slightly over 1.0 and 0.5 microgram/ml/100 mg administered. Analyses of variance found no significant differences among the dosage groups in total apparent clearances (CLT/F), renal clearances (CLR), or nonrenal clearances, which averaged 197, 119, and 78 ml/min, respectively. The half-life increased slightly with dose, averaging 8.4 h overall. The extent of absorption of temafloxacin was quite reproducible, with day-to-day intrasubject variability in minima averaging under 10%. Renal glomerular filtration of unbound drug was the dominant elimination process; however, tubular secretion and reabsorption also appear to occur. Secretion was estimated to account for about 12% of CLT/F during a regimen of 600 mg every 12 h. CLR was relatively constant for urine flow rates above 1 ml/min, but reabsorption appeared to occur under low-flow conditions, resulting in day-versus-night differences in CLR. Intersubject variability in CLT/F over the eightfold range in dosage was only 20%, and 60% of this variance was accounted for by differences in body surface area (or lean body mass), concentration in plasma, and urine flow rate. Overall, it appears that the pharmacokinetics of temafloxacin are essentially linear, reproducible within a subject, and predictable among subjects. PMID:1318680

  1. [Individualization of low-dose oral contraceptives. Pharmacological principles and practical indications for oral contraceptives].

    PubMed

    Cianci, A; De Leo, V

    2007-08-01

    The contraceptive pill has been a revolution of the last 40 years. In Italy, however, it is much less widely used than in other countries. Explanations for this phenomenon range from religious implications and customs to misinformation and word-of-mouth communication of negative experiences. The oral contraceptive pill is often used to correct menstrual disorders, leading to poor results and side-effects. Recent advances in oral contraception have led to a substantial reduction in doses and side-effects. Low-dose pills contain minimal doses of progesterones and estrogens and ensure good control of the menstrual cycle. Although reduction of ethinyl estradiol (EE) concentrations has reduced the incidence of negative systemic side effects such as water retention, edema and swollen breasts, the low estrogen dose may be associated with spotting and hypomenorrhea or amenorrhea in the long term, as well as dyspareunia due to reduced vaginal trophism, which may induce women to suspend use of the drug. It is also true that only one type of estrogen is used in the pill, albeit at different doses, whereas the progesterone may differ and in many cases is the cause of common side-effects. The choice of progesterone therefore involves not only its effect on the endometrium in synergy with estrogen, but also possible residual androgenic activity which may have negative metabolic repercussions. Indeed, addition of a progesterone, especially androgen-derived, attenuates the positive metabolic effects of estrogen. Two new monophasic oral contraceptives were recently released. They contain 30 microg (Yasmin) or 20 muicrog (Yasminelle) EE and a new progesterone, drospirenone, derived from spirolactone, which has antiandrogenic and antimineralcorticoid activity similar to endogenous progesterone. Like progesterone, the drospirenone molecule is an aldosterone antagonist and has a natriuretic effect that opposes the sodium retention effect of EE. It may, therefore, help to prevent the

  2. Single oral paracoccidioidomycosis mimicking other lesions: report of eight cases.

    PubMed

    de Oliveira Gondak, Rogério; Mariano, Fernanda Viviane; dos Santos Silva, Alan Roger; Vargas, Pablo Agustin; Lopes, Márcio Ajudarte

    2012-01-01

    Paracoccidioidomycosis is a fungal infection caused by Paracoccidioides brasiliensis. It is an endemic disease, representing a serious health problem in Latin American countries. This infection primarily affects the lungs and is acquired by inhalation of the fungus. It can spread to other organs and tissues, mainly the oral cavity affecting more adult men from 30 to 50 years of age. On clinical presentation, several signs associated with impaired general and nutritional conditions can be noted. Oral manifestation is more common in the soft palate, gingiva, lower lip, buccal mucosa, and tongue. The classical clinical presentation is a superficial ulcer with granular appearance and hemorrhagic points. Usually, the oral lesion is extensive and generalized. Although uncommon, when the oral manifestation is single, others lesions, particularly squamous cell carcinoma, must be included in the differential diagnosis. In this article, the authors discuss the unusual presentation of eight cases of single oral paracoccidioidomycosis and its diagnostic importance. PMID:21837507

  3. Pharmacokinetics and cell trafficking dynamics of 2-amino-2-[2-(4-octylphenyl)ethyl]propane-1,3-diol hydrochloride (FTY720) in cynomolgus monkeys after single oral and intravenous doses.

    PubMed

    Li, Hongshan; Meno-Tetang, Guy M L; Chiba, Kenji; Arima, Noriyuki; Heining, Peter; Jusko, William J

    2002-05-01

    The pharmacokinetics and cell trafficking dynamics of 2-amino-2-[2-(4-octylphenyl)ethyl]propane-1,3-diol hydrochloride (FTY720), a novel immunosuppressive agent, were examined in cynomolgus monkeys (three males and three females). After single doses of 0.1 mg/kg p.o. or i.v. bolus and 1 mg/kg p.o. were administered to the animals, the concentrations of FTY720, and the numbers of lymphocytes, CD20+CD2-B cells, and CD2+CD20-T cells in blood were measured over 23 days. A linear three-compartment model characterized the time course of FTY720 concentrations with a terminal half-life of about 31 h, clearance of about 0.53 l/h/kg, and bioavailability of about 38%. The dynamic responses were not area under the curve (or dose) proportional for either males or females. An indirect response model with a distribution pool captured the cell trafficking data for all doses for each cell type, where initial blood counts (R(0)) were about 7650, 2100, and 5250 cells/microl; maximum fractional inhibition (I(max)) about 0.88, 0.85, and 0.91; influx (k(in)) about 6014, 1312, and 5662 cells/microl/h; efflux (k(out)) about 0.798, 0.555, and 1.08 h(-1); intercompartmental k(cp) about 0.134, 0.192, and 0.082 h(-1); and intercompartmental k(pc) rate constants about 3.9 x 10(-4), and 0.016 and 8.9 x 10(-6) h(-1) for lymphocytes, B cells, and T cells, respectively. The inhibition concentration IC(50) was about 0.48 microg/l for all cells, which was remarkably low. The apparent distribution volumes of peripheral pool (V(p)) were markedly larger than blood volume (V(b)) for all cells. The I(max) for cell trafficking was achieved at doses smaller than that producing graft protection, indicating stronger central than peripheral effects of this drug. The profound cell trafficking effects of FTY720 can be readily captured and interpreted with an extended indirect response model. PMID:11961052

  4. Efficacy of a single high oxfendazole dose against gastrointestinal nematodes in naturally infected pigs.

    PubMed

    Alvarez, Luis; Saumell, Carlos; Fusé, Luis; Moreno, Laura; Ceballos, Laura; Domingue, Gilbert; Donadeu, Meritxell; Dungu, Baptiste; Lanusse, Carlos

    2013-05-01

    The goal of the current experiment was to assess the clinical efficacy of oxfendazole (OFZ) administered as a single oral dose (30 mg/kg) to pigs naturally parasitized with Ascaris suum, Oesophagostomum spp., Metastrongylus spp. and Trichuris suis. Thirty-six local ecotype piglets were divided into three independent experiments, named I, II and III (n=12 each), respectively. Each experiment involved two different groups (n=6): Untreated Control and OFZ treated. Animals were naturally parasitized with A. suum (Experiments I, II and III), Oesophagostomum spp. (Experiments I and II), T. suis (Experiments II and III) and Metastrongylus spp. (Experiment I). Pigs in the treated group received OFZ (Synanthic(®), Merial Ltd., 9.06% suspension) orally at 30 mg/kg dose. At five (5) days post-treatment, animals were sacrificed and the clinical efficacy of the OFZ treatment was established following the currently available WAAVP guidelines for a controlled efficacy test. None of the animals involved in this experiment showed any adverse events during the study. OFZ treatment given as a single 30 mg/kg oral dose showed a 100% efficacy against all the nematode parasites present in the three experiments. In conclusion, under the current experimental conditions, OFZ orally administered to naturally parasitized piglets at a single dose of 30 mg/kg was safe and highly efficacious (100%) against adult stages of A. suum, Oesophagostomum spp., T. suis and Metastrongylus spp. PMID:23357598

  5. Efficacy of a single high oxfendazole dose against gastrointestinal nematodes in naturally infected pigs.

    PubMed

    Alvarez, Luis; Saumell, Carlos; Fusé, Luis; Moreno, Laura; Ceballos, Laura; Domingue, Gilbert; Donadeu, Meritxell; Dungu, Baptiste; Lanusse, Carlos

    2013-05-01

    The goal of the current experiment was to assess the clinical efficacy of oxfendazole (OFZ) administered as a single oral dose (30 mg/kg) to pigs naturally parasitized with Ascaris suum, Oesophagostomum spp., Metastrongylus spp. and Trichuris suis. Thirty-six local ecotype piglets were divided into three independent experiments, named I, II and III (n=12 each), respectively. Each experiment involved two different groups (n=6): Untreated Control and OFZ treated. Animals were naturally parasitized with A. suum (Experiments I, II and III), Oesophagostomum spp. (Experiments I and II), T. suis (Experiments II and III) and Metastrongylus spp. (Experiment I). Pigs in the treated group received OFZ (Synanthic(®), Merial Ltd., 9.06% suspension) orally at 30 mg/kg dose. At five (5) days post-treatment, animals were sacrificed and the clinical efficacy of the OFZ treatment was established following the currently available WAAVP guidelines for a controlled efficacy test. None of the animals involved in this experiment showed any adverse events during the study. OFZ treatment given as a single 30 mg/kg oral dose showed a 100% efficacy against all the nematode parasites present in the three experiments. In conclusion, under the current experimental conditions, OFZ orally administered to naturally parasitized piglets at a single dose of 30 mg/kg was safe and highly efficacious (100%) against adult stages of A. suum, Oesophagostomum spp., T. suis and Metastrongylus spp.

  6. Single dose NTBC-treatment of hereditary tyrosinemia type I.

    PubMed

    Schlune, A; Thimm, E; Herebian, D; Spiekerkoetter, U

    2012-09-01

    NTBC (2-(2-nitro-4-trifluoromethylbenzoyl)-1,3cyclohexanedione) is the mainstay of treatment in tyrosinemia type 1 (HT 1). The current recommendation is to divide the total daily dose of NTBC into two doses. We monitored the plasma NTBC concentrations in a series of seven patients who were changed from multiple divided doses to a single daily dose of NTBC. Two additional patients were started on a single daily dose of NTBC after the diagnosis of HT 1 was established. In three patients, NTBC kinetics were performed over 6 and 24 hours, respectively. The use of multiple divided doses or a single daily dose did not significantly affect plasma NTBC concentrations or the mean daily dose needed to attain therapeutic plasma NTBC concentrations. Moreover, kinetic studies demonstrated that plasma NTBC concentrations were completely stable over a period of 24 hours with a single dose regimen, as expected given the known NTBC plasma half life of 54 hours. Although these preliminary results need to be confirmed in more patients, our findings show that administration of NTBC in a single daily dose may be as effective as a multiple-dose regimen in reaching therapeutic plasma NTBC concentrations and suppressing succinylacetone formation in patients with HT 1. In fact, single dose treatment may increase patients' compliance with the drug treatment and improve metabolic control.

  7. Oral dose of citrus peel extracts promotes wound repair in diabetic rats.

    PubMed

    Ahmad, M; Ansari, M N; Alam, A; Khan, T H

    2013-10-15

    Diabetic patients wound healing is slower than the healthy individuals. Three citrus peel extracts; Lemon (Citrus limon), Grapes fruits (Citrus paradise) and Orange (Citrus sinensis) promote wound healing in experimental animals. This study investigated the effect of oral treatment with citrus peel extracts on wound repair of the skin of diabetic rats. The extracts were estimated for vitamin C and total carotenoid contents prior to animal study. Diabetes mellitus was induced in rats by intraperitoneal injection of a single dose of streptozotocin (STZ, 75 mg kg(-1) b.wt.). One week after diabetes induction, full thickness excision wounds were made in hyperglycemic rats and were divided groups, each containing 6 rats. The different test group animals were treated with different citrus peel extract orally at the dose of 400 mg kg(-1) body weight daily for 12 days. The blood glucose, body weight and rate of wound closure of each rat were measured every 3rd day during the experimental period. At the end of experiment, granular tissues of wounds were removed and estimated for hydroxylproline and total protein content. The results showed significant reduction in blood glucose and time to wound closure. Tissue growth and collagen synthesis were significantly higher as determined by total protein and hydroxyl proline content. From our experimental data, we propose that oral administration of citrus peel extracts has a therapeutic potential in the treatment of chronic wounds in diabetes.

  8. Peanut Allergen Threshold Study (PATS): validation of eliciting doses using a novel single-dose challenge protocol

    PubMed Central

    2013-01-01

    Background The eliciting dose (ED) for a peanut allergic reaction in 5% of the peanut allergic population, the ED05, is 1.5 mg of peanut protein. This ED05 was derived from oral food challenges (OFC) that use graded, incremental doses administered at fixed time intervals. Individual patients’ threshold doses were used to generate population dose-distribution curves using probability distributions from which the ED05 was then determined. It is important to clinically validate that this dose is predictive of the allergenic response in a further unselected group of peanut-allergic individuals. Methods/Aims This is a multi-centre study involving three national level referral and teaching centres. (Cork University Hospital, Ireland, Royal Children’s Hospital Melbourne, Australia and Massachusetts General Hospital, Boston, U.S.A.) The study is now in process and will continue to run until all centres have recruited 125 participates in each respective centre. A total of 375 participants, aged 1–18 years will be recruited during routine Allergy appointments in the centres. The aim is to assess the precision of the predicted ED05 using a single dose (6 mg peanut = 1.5 mg of peanut protein) in the form of a cookie. Validated Food Allergy related Quality of Life Questionnaires-(FAQLQ) will be self-administered prior to OFC and 1 month after challenge to assess the impact of a single dose OFC on FAQL. Serological and cell based in vitro studies will be performed. Conclusion The validation of the ED05 threshold for allergic reactions in peanut allergic subjects has potential value for public health measures. The single dose OFC, based upon the statistical dose-distribution analysis of past challenge trials, promises an efficient approach to identify the most highly sensitive patients within any given food-allergic population. PMID:24028324

  9. Pharmacokinetics of fluralaner in dogs following a single oral or intravenous administration

    PubMed Central

    2014-01-01

    Background Fluralaner is a novel systemic insecticide and acaricide. The purpose of these studies was to investigate the pharmacokinetic properties of fluralaner in Beagle dogs following single oral or intravenous (i.v.) administration. Methods Following the oral administration of 12.5, 25 or 50 mg fluralaner/kg body weight (BW), formulated as chewable tablets or i.v. administration of 12.5 mg fluralaner/kg BW, formulated as i.v. solution to 24 Beagles, plasma samples were collected until 112 days after treatment. Plasma concentrations of fluralaner were measured using HPLC-MS/MS. Pharmacokinetic parameters were calculated by non-compartmental methods. Results After oral administration, maximum plasma concentrations (Cmax) were reached within 1 day on average. Fluralaner was quantifiable in plasma for up to 112 days after single oral and i.v. treatment. The apparent half-life of fluralaner was 12–15 days and the mean residence time was 15–20 days. The apparent volume of distribution of fluralaner was 3.1 L/kg, and clearance was 0.14 L/kg/day. Conclusions Fluralaner is readily absorbed after single-dose oral administration, and has a long elimination half-life, long mean residence time, relatively high apparent volume of distribution, and low clearance. These pharmacokinetic characteristics help to explain the prolonged activity of fluralaner against fleas and ticks on dogs after a single oral dose. PMID:24606874

  10. Single-dose versus multi-dose vaccine vials for immunization programmes in developing countries.

    PubMed Central

    Drain, Paul K.; Nelson, Carib M.; Lloyd, John S.

    2003-01-01

    Excessive vaccine wastage and safety concerns have prompted the international health community to develop and supply vaccines in formats other than the standard multi-dose vial. This article presents a programmatic and economic comparison of the major differences between the multi-dose vials and single-dose formats used for immunization services in developing countries. Multi-dose vials, in general, sell at a lower per-dose price and occupy less cold-chain capacity than single-dose formats. However, higher wastage rates may offset these benefits, especially for more expensive vaccines. Single-dose formats offer several important programmatic benefits, such as increased vaccination opportunities and improved vaccine safety. One single-dose format, the prefilled auto-disable (AD) device, provides additional injection safety and convenience features because it physically combines the vaccine and AD syringe. Selecting the appropriate vaccine presentation will depend on many factors. However, multi-dose vials are likely to be most appropriate for cheaper vaccines and in settings where cold-chain storage capacity is restricted. Single-dose formats will be most appropriate for more expensive vaccines and where there are problems with unsafe injection practices. Prefilled AD injection devices will be particularly useful in expanding outreach services while eliminating the possibility of needle reuse. PMID:14758432

  11. Pharmacokinetics of pholcodine in healthy volunteers: single and chronic dosing studies.

    PubMed Central

    Chen, Z R; Bochner, F; Somogyi, A

    1988-01-01

    1. The pharmacokinetics of pholcodine after two single doses and after chronic administration were studied in healthy human volunteers. 2. Six subjects received single oral doses of 20 and 60 mg of pholcodine according to a balanced cross-over design with an interval of 3 weeks between the two treatments. Blood and saliva samples and all urine were collected over 168 h after each dosage administration. Subsequently, the same subjects received 20 mg pholcodine 8 hourly orally for 10 days. Blood and saliva samples and all urine were collected during an 8 h dosing interval after the last dose on day 11. 3. Plasma, saliva and urine concentrations of pholcodine were determined by a high performance liquid chromatographic assay. 4. After the single doses, pholcodine was absorbed rapidly (tmax = 1.6 +/- 1.2 h) and eliminated slowly with a mean half-life of 50.1 +/- 4.1 h. The renal clearance of pholcodine was 137 +/- 34 ml min-1 and was inversely correlated with urine pH (r = 0.60) but not with urine flow rate. 26.2 +/- 3.3% of the dose was excreted as unchanged pholcodine after both doses. The concentration of pholcodine in saliva was 3.6 times higher than in plasma. 5. After chronic administration, the pharmacokinetics of pholcodine were not statistically different from the single dose parameters. 6. Pholcodine did not appear to undergo conjugation. The plasma protein binding was 23.5%. Morphine, in unconjugated or conjugated form, was not detected in the urine of any subject after pholcodine administration. PMID:3190994

  12. [Measuring reaction times in healthy probands before and following a single dose of psychotropic drugs].

    PubMed

    Fischer, W; Streubel, F R; Herzer, H; Rabending, G

    1986-10-01

    A single dose of Clomipramin, 50 mg; Amitriptylin, 50 mg; Desipramin, 50 mg; Imipramin, 50 mg; Diazepam, 10 mg; Carbamazepin, 200 mg; Haloperidol, 3 mg; were each administered orally, and Clomipramin, 25 mg was administered intravenously, and reaction times were measured and compared with those obtained after administering a placebo. The statistical examination was conducted using Wilcoxon's test. In the case of Amitriptylin, Diazepam, and Haloperidol, there was a statistically significant reduction in the reaction times.

  13. Seroconversion status after single dose and double doses of varicella vaccination in children with leukemia.

    PubMed

    Cakir, F Betul; Timur, Cetin; Yoruk, Asim; Cakir, Erkan; Ayhan, Aylin Canbolat

    2012-03-01

    Although varicella is a benign self-limiting disease in healthy children, it can be fatal when it occurs in immunocompromised hosts. Despite that immunosuppressed children are suggested to require 2 doses of vaccine to achieve seroconversion, conflicting results are reported in the literature. The aim of this study was to investigate the seroconversion status and mean antibody titers at first year after single dose and double doses of varicella vaccination in acute lymphoblastic leukemia patients. Patients with leukemia in remission for at least 1 year who were seronegative for varicella-zoster virus immunoglobulin G (IgG) were vaccinated. Titers above the cutoff level (0.65) were accepted as seroconversion. Seventeen patients were vaccinated with single dose whereas 24 patients were vaccinated with double doses. Mean prevaccination antibody titers were 0.56 ± 0.05 in patients with single dose and 0.51 ± 0.08 in patients with double doses (P > .05, Student t test). The mean antibody titers at first year were 0.61 ± 0.05 in patients with single-dose vaccination (P > .05, Wilcoxon signed-rank test) and 1.48 ± 0.04 in patients with double doses (P < .001, Wilcoxon signed-rank test). Seroconversion after single-dose vaccination was achieved in 29% of patients (n = 5/17) and in 75% of patients with double doses (n = 18/24) at first year (P = .004, chi-square test). These results suggest that seroconversion after single-dose vaccination might not persist at first year in malignancy patients. Double doses should be applied in order to provide long-term seroconversion.

  14. Pharmacokinetic and pharmacodynamic profile of supratherapeutic oral doses of Δ(9) -THC in cannabis users.

    PubMed

    Lile, Joshua A; Kelly, Thomas H; Charnigo, Richard J; Stinchcomb, Audra L; Hays, Lon R

    2013-07-01

    Oral Δ(9) -tetrahydrocannabinol (Δ(9) -THC) has been evaluated as a medication for cannabis dependence, but repeated administration of acute oral doses up to 40 mg has not been effective at reducing drug-taking behavior. Larger doses might be necessary to affect cannabis use. The purpose of the present study was therefore to determine the physiological and behavioural effects of oral Δ(9) -THC at acute doses higher than those tested previously. The pharmacokinetic and pharmacodynamic profile of oral Δ(9) -THC, administered in ascending order in 15 mg increments across separate sessions, up to a maximum of 90 mg, was determined in seven cannabis users. Five subjects received all doses and two experienced untoward side effects at lower doses. Δ(9) -THC produced a constellation of effects consistent with previous clinical studies. Low cannabinoid concentrations were associated with significant effects on drug-sensitive measures, although progressively greater levels did not lead to proportionately larger drug effects. Considerable variability in Cmax and tmax was observed. Doses of oral Δ(9) -THC larger than those tested previously can be administered to individuals with a history of cannabis use, although given the pharmacokinetic variability of oral Δ(9) -THC and individual differences in sensitivity, individualized dose adjustment is needed to avoid side effects and maximize therapeutic response.

  15. Flurbiprofen interaction with single doses of atenolol and propranolol.

    PubMed Central

    Webster, J; Petrie, J C; McLean, I; Hawksworth, G M

    1984-01-01

    In patients with mild hypertension, flurbiprofen in a dose of 100 mg daily for 7 days attenuated the hypotensive effect of a single dose of propranolol 80 mg but not of atenolol 100 mg. The attenuation was not due to an effect on the pharmacokinetic profile of either propranolol or atenolol. An alternative explanation is required. PMID:6529525

  16. In Vivo Human Time-Exposure Study of Orally Dosed Commercial Silver Nanoparticles

    PubMed Central

    Munger, Mark A.; Radwanski, Przemyslaw; Hadlock, Greg C.; Stoddard, Greg; Shaaban, Akram; Falconer, Jonathan; Grainger, David W.; Deering-Rice, Cassandra E.

    2013-01-01

    Background Human biodistribution, bioprocessing and possible toxicity of nanoscale silver receives increasing health assessment. Methods We prospectively studied commercial 10- and 32-ppm nanoscale silver particle solutions in a single-blind, controlled, cross-over, intent-to-treat, design. Healthy subjects (n=60) underwent metabolic, blood counts, urinalysis, sputum induction, and chest and abdomen magnetic resonance imaging. Silver serum and urine content was determined. Results No clinically important changes in metabolic, hematologic, or urinalysis measures were identified. No morphological changes were detected in the lungs, heart or abdominal organs. No significant changes were noted in pulmonary reactive oxygen species or pro-inflammatory cytokine generation. Conclusion In vivo oral exposure to these commercial nanoscale silver particle solutions does not prompt clinically important changes in human metabolic, hematologic, urine, physical findings or imaging morphology. Further study of increasing time exposure and dosing of silver nanoparticulate silver, and observation of additional organ systems is warranted to assert human toxicity thresholds. PMID:23811290

  17. Artemether-lumefantrine nanostructured lipid carriers for oral malaria therapy: Enhanced efficacy at reduced dose and dosing frequency.

    PubMed

    Prabhu, Priyanka; Suryavanshi, Shital; Pathak, Sulabha; Sharma, Shobhona; Patravale, Vandana

    2016-09-10

    Artemether-lumefantrine (ARM-LFN) is a World Health Organization (WHO) approved fixed-dose combination having low solubility and poor oral bioavailability. Nanostructured lipid carriers (NLC) were developed to enhance the oral efficacy of this combination using the microemulsion template technique. They were characterized for drug content, entrapment efficiency, size distribution, in vitro release, antimalarial efficacy, and toxicity. The NLC showed sustained drug release. The recommended adult therapeutic dose is 80mg ARM and 480mg LFN (4 tablets) twice a day, which amounts to 160mg ARM and 960mg LFN daily. ARM-LFN NLC given once a day at 1/5 of therapeutic dose (16mg ARM and 96mg LFN) showed complete parasite clearance and 100% survival in Plasmodium berghei-infected mice. 33% of the mice treated with marketed tablets twice a day at the therapeutic dose showed late-stage recrudescence. Thus, NLC showed enhanced efficacy at 1/10 of the daily dose of ARM-LFN. The 10-fold reduced daily dose was formulated in two soft gelatin capsules thus reducing the number of units to be taken at a time by the patient. The capsules showed good stability at room temperature for a year. The NLC were found to be safe in rats. The biocompatible NLC developed using an industrially feasible technique offer a promising solution for oral malaria therapy. PMID:27421912

  18. Interdisciplinary science and the design of a single-dose antibiotic therapy.

    PubMed

    Curatolo, William

    2011-09-01

    Azithromycin is a unique antibiotic due to its serum half-life of 69 h. This half-life is long enough to permit administration of an entire course of therapy in a single dose, if the gastrointestinal (GI) side effects of such a high dose can be minimized. A series of exploratory clinical pharmacology studies were carried out to understand the site-specific absorption and toleration constraints involved in delivering a 2 g oral single-dose regimen. These studies demonstrated that (a) GI side effects were locally mediated in the GI tract, (b) the duodenum was more sensitive than the ileocecal region, and (c) colonic absorption was limited. A novel controlled release suspension dosage form was designed to meet these constraints, and was shown to deliver the desired systemic dose with acceptable toleration. This dosage form, Zmax®, is an oral powder-for-constitution which possesses two major features: (a) 200 μm controlled release microspheres which release the drug as they transit down the small intestine, and (b) alkalizing agents which raise the pH of the gastric milieu for ~20 min to minimize gastric release of the drug (which has high solubility at low pH), in order to minimize exposure of the drug to the sensitive duodenal region. The ability to provide a high single dose of azithromycin results in "front-loading" the mononuclear and polymorphonuclear leukocytes which concentrate the drug and carry it to sites of infection. This provides high drug concentrations early on at infection sites, when the bacterial burden is greatest, potentially improving efficacy and potentially overcoming resistant bacterial strains. Finally, this revolutionary single dose formulation gives 100% compliance, which maximizes the likelihood of therapeutic success.

  19. Chemotherapy of onchocerciasis with high doses of diethylcarbamazine or a single dose of ivermectin: microfilaria levels and side effects.

    PubMed

    Albiez, E J; Newland, H S; White, A T; Kaiser, A; Greene, B M; Taylor, H R; Büttner, D W

    1988-03-01

    Fifty adult male subjects with moderate to heavy onchocerciasis from the Liberian rain forest were selected for a double-blind placebo-controlled chemotherapy study. The effects of high doses of diethylcarbamazine (DEC) - 30 mg/kg/d - over one week preceded by a one week initial treatment with normal oral doses of DEC or DEC lotion were compared with a single dose of ivermectin (150 micrograms/kg) and placebo. During the initial treatment DEC tablets or lotion caused distinctly more frequent and severe reactions than did invermectin. The reactions to ivermectin did not differ from those of the placebo patients. High doses of DEC caused, in about half of the patients, headache, dizziness, nausea or vomiting. DEC markedly increased the number of corneal microfilariae and of corneal opacities compared to ivermectin. All changes resolved with a return to pretreatment findings two months after treatment. The three treatment groups showed no differences at the ten months follow-up. In all treated patients skin microfilaria counts fell almost to zero by the end of the two week therapy. In the ivermectin group microfilaria counts remained significantly lower than in the DEC patients at the two and ten months examinations. In summary, ivermectin was much better tolerated than DEC and had a longer lasting effect on the microfilariae in the skin. Since high doses of DEC were less effective and caused more frequent and severe side effects, this approach cannot be recommended for treatment of onchocerciasis.

  20. Acute effects of oral low doses of pyridostigmine on simple visual discrimination and unconditioned consummatory acts in rats.

    PubMed

    Liu, W F

    1992-01-01

    Pyridostigmine bromide (Pyr), a reversible cholinesterase inhibitor, is currently suggested to be the most effective pretreatment drug against intoxication with potent organophosphates (OP). This investigation was conducted to determine if oral low doses of Pyr would affect performance of a simple visual discrimination task, and further to assess the alterations of motor or motivational function that might underlie the performance deficits in the water-deprived rats. Rats were trained extensively on a successive light-intensity discrimination implemented with the use of a multiple schedule. The multiple schedule consisted of one fixed-ratio (FR-10) and one differential reinforcement of low rates (DRL-10 s) component, which were signalled by the 10-s discriminative stimuli of bright (S+) and dim (S-) houselights, respectively, in simple alternation. The light intensity difference (S-/S+) was about 0.6. Pyr, at doses (3-12 mg/kg), which did not cause overt symptoms, moderately decreased S+ respondings but did not affect S- respondings. The ratio of S+/S- respondings, an index of discrimination performance, was moderately decreased. Over the range of doses evaluated, Pyr also attenuated the corresponding water intake in a dose-dependent manner, but it did not significantly affect locomotor activity. The lowest effective doses of the above affected behaviors were virtually identical (6 mg/kg). These results suggest that the disruptive effects of a single oral low dose of Pyr on the rat operant performance involve motivational dysfunction rather than motor impairment.

  1. Effect of beam arrangement on oral cavity dose in external beam radiotherapy of nasopharyngeal carcinoma

    SciTech Connect

    Wu, Vincent W.C.; Yang Zhining; Zhang Wuzhe; Wu Lili; Lin Zhixiong

    2012-07-01

    This study compared the oral cavity dose between the routine 7-beam intensity-modulated radiotherapy (IMRT) beam arrangement and 2 other 7-beam IMRT with the conventional radiotherapy beam arrangements in the treatment of nasopharyngeal carcinoma (NPC). Ten NPC patients treated by the 7-beam routine IMRT technique (IMRT-7R) between April 2009 and June 2009 were recruited. Using the same computed tomography data, target information, and dose constraints for all the contoured structures, 2 IMRT plans with alternative beam arrangements (IMRT-7M and IMRT-7P) by avoiding the anterior facial beam and 1 conventional radiotherapy plan (CONRT) were computed using the Pinnacle treatment planning system. Dose-volume histograms were generated for the planning target volumes (PTVs) and oral cavity from which the dose parameters and the conformity index of the PTV were recorded for dosimetric comparisons among the plans with different beam arrangements. The dose distributions to the PTVs were similar among the 3 IMRT beam arrangements, whereas the differences were significant between IMRT-7R and CONRT plans. For the oral cavity dose, the 3 IMRT beam arrangements did not show significant difference. Compared with IMRT-7R, CONRT plan showed a significantly lower mean dose, V30 and V-40, whereas the V-60 was significantly higher. The 2 suggested alternative beam arrangements did not significantly reduce the oral cavity dose. The impact of varying the beam angles in IMRT of NPC did not give noticeable effect on the target and oral cavity. Compared with IMRT, the 2-D conventional radiotherapy irradiated a greater high-dose volume in the oral cavity.

  2. Pharmacokinetics of marbofloxacin after single intravenous and repeat oral administration to cats.

    PubMed

    Albarellos, G A; Montoya, L; Landoni, M F

    2005-09-01

    The pharmacokinetic properties of marbofloxacin, a third generation fluoroquinolone, were investigated in six cats after single intravenous (IV) and repeat oral (PO) administration at a daily dose of 2 mg/kg. Marbofloxacin serum concentration was analysed by microbiological assay using Klebsiella pneumoniae ATCC 10031 as micro-organism test. Serum marbofloxacin disposition was best described by bicompartmental and mono-compartmental open models with first-order elimination after IV and oral dosing respectively. After IV administration, distribution was rapid (T(1/2(d)) 0.23+/-0.24 h) and wide, as reflected by the steady-state volume of distribution of 1.01+/-0.15 L/kg. Elimination from the body was slow with a body clearance of 0.09+/-0.02 L/h kg and a T(1/2) of 7.98+/-0.57 h. After repeat oral administration, absorption half-life was 0.86+/-1.59 h and T(max) of 1.94+/-2.11 h. Bioavailability was almost complete (99+/-29%) with a peak plasma concentration at the steady-state of 1.97+/-0.61 mug/mL. Drug accumulation was not significant after six oral administrations. Calculation of efficacy predictors showed that marbofloxacin has good therapeutic profile against Gram-negative and Gram-positive bacteria with a MIC(50) value <0.25 microg/mL.

  3. Reproductive toxicity of a single dose of 1,3-dinitrobenzene in two ages of young adult male rats

    EPA Science Inventory

    These studies evaluated the reproductive response and the possible influence of testicular maturation on the reproductive parameters, in male rats treated with 1,3-dinitrobenzene (m-DNB). Young adult male rats (75 or 105 days of age) were given a single oral dose of 0, 8, 16, 24,...

  4. Prolonged and symptomatic bradycardia following a single dose of fingolimod.

    PubMed

    Faber, Hans; Fischer, Hans-Jörg; Weber, Frank

    2013-01-01

    Fingolimod-related bradycardia is usually asymptomatic, reaches its nadir within 6 hours post-dose and recovers spontaneously. Here we report the case of a 30-year-old MS patient with vagotonia who developed symptomatic bradycardia with 33 beats per minute at nadir 39 hours after a single dose of fingolimod. Bradycardia was responsive to atropine, but returned within 2 hours. Overall, it took a week until the patient recovered. Extended monitoring is advised in patients with symptomatic bradycardia.

  5. Toxicity of zinc oxide nanoparticles in rats treated by two different routes: single intravenous injection and single oral administration.

    PubMed

    Choi, Jonghye; Kim, Heyjin; Kim, Pilje; Jo, Eunhye; Kim, Hyun-Mi; Lee, Moo-Yeol; Jin, Seon Mi; Park, Kwangsik

    2015-01-01

    Toxicokinetics of zinc oxide nanoparticles (ZnONP) was studied in rats via a single intravenous (iv) injection and a single oral administration (3 mg/kg or 30 mg/kg), respectively. Blood concentrations of zinc (Zn) were monitored for 7 d and tissue distribution were determined in liver, kidneys, lung, spleen, thymus, brain, and testes. To ascertain the excretion of ZnONP, Zn levels in urine and feces were measured for 7 d. ZnONP were not readily absorbed from the gastrointestinal tract (GIT) after oral administration and were excreted mostly in feces. When the nanoparticles were injected iv to rats at a dose of 30 mg/kg, peak concentration appeared at 5 min but returned to normal range by d 2 (48 h after injection). ZnONP were distributed mainly to liver, kidneys, lung, and spleen, but not to thymus, brain, and testes. The distribution level was significantly decreased to normal by d 7. Feces excretion levels after iv injection supported biliary excretion of ZnONP. In rats injected iv with 30 mg/kg, mitotic figures in hepatocytes were significantly increased and multifocal acute injuries with dark brown pigment were noted in lungs, while no significant damage was observed in rats treated orally with the same dosage.

  6. Reproductive toxicity in rats with crystal nephropathy following high doses of oral melamine or cyanuric acid.

    PubMed

    Stine, Cynthia B; Reimschuessel, Renate; Keltner, Zachary; Nochetto, Cristina B; Black, Thomas; Olejnik, Nicholas; Scott, Michael; Bandele, Omari; Nemser, Sarah M; Tkachenko, Andriy; Evans, Eric R; Crosby, Tina C; Ceric, Olgica; Ferguson, Martine; Yakes, Betsy J; Sprando, Robert

    2014-06-01

    The industrial chemical melamine was used in 2007 and 2008 to raise the apparent protein content in pet feed and watered down milk, respectively. Because humans may be exposed to melamine via several different routes into the human diet as well as deliberate contamination, this study was designed to characterize the effect of high dose melamine or cyanuric acid oral exposure on the pregnant animal and developing fetus, including placental transfer. Clear rectangular crystals formed following a single triazine exposure which is a different morphology from the golden spherulites caused by combined exposure or the calculi formed when melamine combines with endogenous uric acid. Crystal nephropathy, regardless of cause, induces renal failure which in turn has reproductive sequelae. Specifically, melamine alone-treated dams had increased numbers of early and late fetal deaths compared to controls or cyanuric acid-treated dams. As melamine was found in the amniotic fluid, this study confirms transfer of melamine from mammalian mother to fetus and our study provides evidence that cyanuric acid also appears in the amniotic fluid if mothers are exposed to high doses.

  7. A single dose of citalopram increases fear recognition in healthy subjects.

    PubMed

    Browning, M; Reid, C; Cowen, P J; Goodwin, G M; Harmer, C J

    2007-09-01

    We have previously shown that a single dose of intravenous citalopram in healthy volunteers enhances the detection of fearful facial expressions, suggesting an effect of acute selective serotonin re-uptake inhibitor (SSRI) treatment on the processing of anxiety-related stimuli. The aim of the present study was to confirm and extend this finding by studying the effects of a single dose of oral citalopram on a range of tasks designed to assess different aspects of emotional processing. A total of 32 healthy volunteers were randomly allocated to double-blind treatment with either citalopram 20 mg orally or placebo. Participants then completed a series of tasks assessing emotional aspects of attention (visual-probe task), perception (categorization of facial affect), memory (emotional memory task) and reactivity to threat (emotion potentiated startle). Relative to placebo-treated subjects, participants treated with citalopram demonstrated improved recognition of fearful faces and increased baseline startle response. However, the citalopram group also showed an attentional bias towards positive words. Our data suggest that acute oral citalopram increases the processing of anxiety-related stimuli in healthy volunteers. This mechanism could underlie the known tendency of SSRIs to increase anxiety in patients early in treatment. Our data also suggests that some of the positive biases in emotional processing produced by SSRI treatment might be detectable at the beginning of treatment.

  8. A double-blind, placebo-controlled evaluation of the effect of oral doses of rizatriptan 10 mg on oral contraceptive pharmacokinetics in healthy female volunteers.

    PubMed

    Shadle, C R; Liu, G; Goldberg, M R

    2000-03-01

    Rizatriptan (MAXALT), a potent, oral 5-HT1B/1D agonist with a rapid onset of action, is available now for the acute treatment of migraine. This study examined the pharmacokinetic and clinical interaction between rizatriptan 10 mg and the components (ethinyl estradiol [EE] 35 micrograms and norethindrone [NET] 1.0 mg) of a well-established oral contraceptive combination product, ORTHO-NOVUM 1/35. Levels of sex hormone binding globulin (SHBG), a protein increased by EE to which NET binds, were also examined. In this two-period crossover study, 20 healthy young female subjects received a coadministration of 8 days of rizatriptan treatment (6 days of single-dose 10 mg rizatriptan and 2 days of multiple-dose rizatriptan, 10 mg q 4 hours for three doses, giving a total daily dose of 30 mg on Days 7 and 8) or matching placebo along with their daily dose (one tablet) of ORTHO-NOVUM 1/35 within their oral contraceptive cycle. Plasma was sampled for EE, NET, and SHBG concentrations. Safety evaluations included routine laboratory safety studies, physical examinations, and monitoring for ECG, vital signs, and adverse events. There were no statistically significant differences in any of the pharmacokinetic parameters of EE or NET between the rizatriptan and placebo treatment periods, thus indicating that rizatriptan had no meaningful effect on the disposition of either the EE or the NET component of ORTHO-NOVUM 1/35. The SHBG concentration did not change throughout the entire study. Clinically, coadministration of rizatriptan with ORTHO-NOVUM 1/35 was well tolerated. Blood pressure, heart rate, and temperature showed no consistent trend or clinically important changes. Adverse events following coadministration of rizatriptan with ORTHO-NOVUM 1/35 were similar to those reported when placebo was given with ORTHO-NOVUM 1/35. The findings of this study indicate that there is little potential for dosages as high as 30 mg/day, the maximum recommended dosing schedule, of rizatriptan

  9. Prolonged central mu-opioid receptor occupancy after single and repeated nalmefene dosing.

    PubMed

    Ingman, Kimmo; Hagelberg, Nora; Aalto, Sargo; Någren, Kjell; Juhakoski, Auni; Karhuvaara, Sakari; Kallio, Antero; Oikonen, Vesa; Hietala, Jarmo; Scheinin, Harry

    2005-12-01

    The opioid antagonist nalmefene offers an alternative to traditional pharmacological treatments for alcoholism. The present study was designed to investigate the relationship between nalmefene plasma concentration and central mu-opioid receptor occupancy after a clinically effective dose (20 mg, orally). Pharmacokinetics and mu-opioid receptor occupancy of nalmefene after single and repeated dosing over 7 days was studied in 12 healthy subjects. Serial blood samples were obtained after both dosings, and pharmacokinetic parameters for nalmefene and main metabolites were determined. Central mu-opioid receptor occupancy of nalmefene was measured with positron emission tomography (PET) and [(11)C]carfentanil at four time points (3, 26, 50, 74 h) after both dosings. Nalmefene was rapidly absorbed in all subjects. The mean t(1/2) of nalmefene was 13.4 h after single and repeated dosing. The accumulation of nalmefene and its main metabolites in plasma during the repeated dosing period was as expected for a drug with linear pharmacokinetics, and steady-state was reached for all analytes. Both nalmefene dosings resulted in a very high occupancy at mu-opioid receptors (87-100%), and the decline in the occupancy was similar after both dosings but clearly slower than the decline in the plasma concentration of nalmefene or metabolites. High nalmefene occupancy (83-100%) persisted at 26 h after the dosings. The prolonged mu-opioid receptor occupancy by nalmefene indicates slow dissociation of the drug from mu-opioid receptors. These results support the rational of administering nalmefene when needed before alcohol drinking, and they additionally suggest that a high mu-opioid receptor occupancy can be maintained when nalmefene is taken once daily.

  10. Replacing the measles ten-dose vaccine presentation with the single-dose presentation in Thailand.

    PubMed

    Lee, Bruce Y; Assi, Tina-Marie; Rookkapan, Korngamon; Connor, Diana L; Rajgopal, Jayant; Sornsrivichai, Vorasith; Brown, Shawn T; Welling, Joel S; Norman, Bryan A; Chen, Sheng-I; Bailey, Rachel R; Wiringa, Ann E; Wateska, Angela R; Jana, Anirban; Van Panhuis, Willem G; Burke, Donald S

    2011-05-12

    Introduced to minimize open vial wastage, single-dose vaccine vials require more storage space and therefore may affect vaccine supply chains (i.e., the series of steps and processes involved in distributing vaccines from manufacturers to patients). We developed a computational model of Thailand's Trang province vaccine supply chain to analyze the effects of switching from a ten-dose measles vaccine presentation to each of the following: a single-dose measles-mumps-rubella vaccine (which Thailand is currently considering) or a single-dose measles vaccine. While the Trang province vaccine supply chain would generally have enough storage and transport capacity to accommodate the switches, the added volume could push some locations' storage and transport space utilization close to their limits. Single-dose vaccines would allow for more precise ordering and decrease open vial waste, but decrease reserves for unanticipated demand. Moreover, the added disposal and administration costs could far outweigh the costs saved from preventing open vial wastage. PMID:21439313

  11. Evaluation of fipronil oral dosing to cattle for control of adult and larval sand flies under controlled conditions.

    PubMed

    Poché, Richard M; Garlapati, Rajesh; Singh, Mutum I; Poché, David M

    2013-07-01

    Visceral Leishmaniasis (VL) is a vector-borne disease endemic to the Indian subcontinent. The Phlebotomus genus of sand flies is the vector for VL in the Old World, with the vector on the Indian Subcontinent being Phlebotomus argentipes. Cattle are a commodity in this region and a frequent host source of P. argentipes bloodmeals. The purpose of this study was to determine the efficacy of a single oral dose fipronil against adult and larval P. argentipes. Ten Bos indicus cattle were used during the study in a controlled environment. The study was conducted in Bihar, India, and involved adult and larval bioassays using laboratory-reared P. argentipes. The results were positive in that they led to up to 100% mortality in both adult and larval sand flies over a 21-d period after a single dose of fipronil.

  12. Antiretroviral Therapies in Women after Single-Dose Nevirapine Exposure

    PubMed Central

    Lockman, S.; Hughes, M.D.; McIntyre, J.; Zheng, Y.; Chipato, T.; Conradie, F.; Sawe, F.; Asmelash, A.; Hosseinipour, M.C.; Mohapi, L.; Stringer, E.; Mngqibisa, R.; Siika, A.; Atwine, D.; Hakim, J.; Shaffer, D.; Kanyama, C.; Wools-Kaloustian, K.; Salata, R.A.; Hogg, E.; Alston-Smith, B.; Walawander, A.; Purcelle-Smith, E.; Eshleman, S.; Rooney, J.; Rahim, S.; Mellors, J.W.; Schooley, R.T.; Currier, J.S.

    2010-01-01

    BACKGROUND Peripartum administration of single-dose nevirapine reduces mother-to-child transmission of human immunodeficiency virus type 1 (HIV-1) but selects for nevirapine-resistant virus. METHODS In seven African countries, women infected with HIV-1 whose CD4+ T-cell counts were below 200 per cubic millimeter and who either had or had not taken single-dose nevirapine at least 6 months before enrollment were randomly assigned to receive antiretroviral therapy with tenofovir–emtricitabine plus nevirapine or tenofovir-emtricitabine plus lopinavir boosted by a low dose of ritonavir. The primary end point was the time to confirmed virologic failure or death. RESULTS A total of 241 women who had been exposed to single-dose nevirapine began the study treatments (121 received nevirapine and 120 received ritonavir-boosted lopinavir). Significantly more women in the nevirapine group reached the primary end point than in the ritonavir-boosted lopinavir group (26% vs. 8%) (adjusted P = 0.001). Virologic failure occurred in 37 (28 in the nevirapine group and 9 in the ritonavir-boosted lopinavir group), and 5 died without prior virologic failure (4 in the nevirapine group and 1 in the ritonavir-boosted lopinavir group). The group differences appeared to decrease as the interval between single-dose nevirapine exposure and the start of antiretroviral therapy increased. Retrospective bulk sequencing of baseline plasma samples showed nevirapine resistance in 33 of 239 women tested (14%). Among 500 women without prior exposure to single-dose nevirapine, 34 of 249 in the nevirapine group (14%) and 36 of 251 in the ritonavir-boosted lopinavir group (14%) had virologic failure or died. CONCLUSIONS In women with prior exposure to peripartum single-dose nevirapine (but not in those without prior exposure), ritonavir-boosted lopinavir plus tenofovir–emtricitabine was superior to nevirapine plus tenofovir–emtricitabine for initial antiretroviral therapy. (Funded by the National

  13. Single-dose intrathecal analgesia to control labour pain

    PubMed Central

    Minty, R.G.; Kelly, Len; Minty, Alana; Hammett, D.C.

    2007-01-01

    OBJECTIVE To examine the safety and efficacy of single-dose spinal analgesia (intrathecal narcotics [ITN]) during labour. QUALITY OF EVIDENCE MEDLINE was searched and the references of 2 systematic reviews and a meta-analysis were reviewed to find articles on obstetric analgesia and pain measurement. The 33 articles selected included 14 studies, 1 meta-analysis, and 2 systematic reviews, all providing level I evidence. MAIN MESSAGE The literature supports use of ITN as a safe and effective alternative to epidural anesthesia. The recent decrease in rates of episiotomies and use of forceps during deliveries means patients require less dense perineal anesthesia. The advantageof single-dose ITN is that fewer physicians and nurses are needed to administer it even though its safety and effectiveness are comparable with other analgesics. Use of ITN is associated with a shorter first stage of labour and more rapid cervical dilation. A combination of 2.5 mg of bupivacaine, 25 μg of fentanyl, and 250 μg of morphine intrathecally usually provides a 4-hour window of acceptable analgesia for patients without complications not anticipating protracted labour. The evolution in dosing of ITN warrants a re-examination of its usefulness in modern obstetric practice. CONCLUSION Physicians practising modern obstetrics in rural and small urban centres might find single-dose ITN a useful alternative to parenteral or epidural analgesia for appropriately selected patients. PMID:17872679

  14. A pilot open label, single dose trial of fenobam in adults with fragile X syndrome

    PubMed Central

    Berry-Kravis, E; Hessl, D; Coffey, S; Hervey, C; Schneider, A; Yuhas, J; Hutchison, J; Snape, M; Tranfaglia, M; Nguyen, D V; Hagerman, R

    2009-01-01

    Objective: A pilot open label, single dose trial of fenobam, an mGluR5 antagonist, was conducted to provide an initial evaluation of safety and pharmacokinetics in adult males and females with fragile X syndrome (FXS). Methods: Twelve subjects, recruited from two fragile X clinics, received a single oral dose of 50–150 mg of fenobam. Blood for pharmacokinetic testing, vital signs and side effect screening was obtained at baseline and numerous time points for 6 h after dosing. Outcome measures included prepulse inhibition (PPI) and a continuous performance test (CPT) obtained before and after dosing to explore the effects of fenobam on core phenotypic measures of sensory gating, attention and inhibition. Results: There were no significant adverse reactions to fenobam administration. Pharmacokinetic analysis showed that fenobam concentrations were dose dependent but variable, with mean (SEM) peak values of 39.7 (18.4) ng/ml at 180 min after the 150 mg dose. PPI met a response criterion of an improvement of at least 20% over baseline in 6 of 12 individuals (4/6 males and 2/6 females). The CPT did not display improvement with treatment due to ceiling effects. Conclusions: Clinically significant adverse effects were not identified in this study of single dose fenobam across the range of dosages utilised. The positive effects seen in animal models of FXS treated with fenobam or other mGluR5 antagonists, the apparent lack of clinically significant adverse effects, and the potential beneficial clinical effects seen in this pilot trial support further study of the compound in adults with FXS. PMID:19126569

  15. Cholinolytic antagonism to the disruptive effects of oral low doses of pyridostigmine on simple discrimination performance in rats.

    PubMed

    Liu, W F

    1991-12-01

    We have previously reported that acute oral administration of low doses (less than or equal to 12 mg/kg) of pyridostigmine bromide (PYR) to rats resulted in a dose-dependent decrement in reinforcement rate under two different multiple schedules of response-produced water presentation, which involved motivational dysfunction rather than motor impairment and alterations in visual perception. The purpose of the present investigation was to examine further if the anticipated operant behavioral deficits of PYR are mediated by central and/or peripheral cholinergic mechanisms. Lever-press responses of male Sprague-Dawley rats were maintained under a multiple fixed-ratio GO/differential-reinforcement-of-low-rate NO GO, brightness discrimination, schedule of water reinforcement. The effects of the muscarinic antagonists atropine (ATR) and methylatropine (MAT), both at doses of 0.25, 0.5 and 1.0 mg/kg (SC), against a single oral low dose of PYR (12 mg/kg)-induced behavioral disruption were compared. ATR partially antagonized the reinforcement loss of PYR with concomitant dose-related increases in nonreinforced responses, whereas MAT completely antagonized the reinforcement loss without affecting the frequency of nonreinforced responses. These results suggest that in rats, the debilitating effects of oral PYR on operant behavior are primarily due to the stimulation of peripheral muscarinic receptors via its anticholinesterase activity. The increments of nonreinforced responses observed after coadministration of PYR with ATR may reflect a central, excitatory action of ATR which could affect the discrimination performance. The present results have practical implications for the clinical utilization of PYR in combination with the peripherally active muscarinic antagonist in situations where optimal performance is required.

  16. Combined administration of low-dose gossypol acetic acid with desogestrel/mini-dose ethinylestradiol/testosterone undecanoate as an oral contraceptive for men.

    PubMed

    Yang, Zhan-Jun; Ye, Wei-San; Cui, Guang-Hui; Guo, Yan; Xue, She-Pu

    2004-09-01

    To evaluate the efficacy and feasibility of a new regimen of low-dose gossypol acetic acid (GA) combined with desogestrel/ethinylestradiol and testosterone undecanoate (DSG/E/TU) as a male contraceptive, adult male rats were fed orally with GA (12.5 mg/kg/day) and DSG (0.125 mg/kg)/E (0.025 mg/kg)/TU (100 mg/kg) daily for 8 weeks as loading dose until infertility, and a similar low dose of GA alone for infertility maintenance. Control animals were administered a single low dose of GA (12.5 mg/kg/day) or DSG (0.125 mg/kg)/E (0.025 mg/kg)/TU (100 mg/kg), and vehicle, respectively. Results demonstrated that the combined dosage regimen could damage epididymal sperm motility and density, and induce infertility within 8 weeks in rats; the infertility could be consistently sustained by giving single GA (12.5 mg/kg/day), and was reversible in about 8 weeks following withdrawal of gossypol. The regimen rendered treated male rats with spermiation failure within a period of 6-20 weeks of treatment. Also, the serum luteinizing hormone, follicle-stimulating hormone and testicular interstitial fluid testosterone levels showed a transient decrease at the end of 6 or 8 weeks, which returned to control levels after 8 weeks of recovery phase. No hypokalemia or other adverse effects in viscera were observed. These results provide a promising approach to using the new regimen for the development of an effective and reversible oral male contraceptive. PMID:15325889

  17. Pharmacokinetics of eight anticoagulant rodenticides in mice after single oral administration.

    PubMed

    Vandenbroucke, V; Bousquet-Melou, A; De Backer, P; Croubels, S

    2008-10-01

    The first aim of the study was to investigate the pharmacokinetics of eight anticoagulant rodenticides (brodifacoum, bromadiolone, chlorophacinone, coumatetralyl, difenacoum, difethialone, flocoumafen and warfarin) in plasma and liver of the mouse after single oral administration. Eight groups of mice dosed orally with a different anticoagulant rodenticide in a dose equal to one-half the lethal dose 50 (LD(50)), were killed at various times up to 21 days after administration. The eight anticoagulant rodenticides were assayed in plasma and liver by an LC-ESI-MS/MS method. Depending on the compound, the limit of quantification was set at 1 or 5 ng/mL in plasma. In liver, the limit of quantification was set at 250 ng/g for coumatetralyl and warfarin and at 100 ng/g for the other compounds. The elimination half-lives in plasma for first-generation rodenticides were shorter than those for second-generation rodenticides. Coumatetralyl, a first-generation product, had a plasma elimination half-life of 0.52 days. Brodifacoum, a second-generation product, showed a plasma elimination half-life of 91.7 days. The elimination half-lives in liver varied from 15.8 days for coumatetralyl to 307.4 days for brodifacoum. The second aim of the study was to illustrate the applicability of the developed method in a clinical case of a dog suspected of rodenticide poisoning. PMID:19000263

  18. Disposition of 2-hydroxy-4-methoxybenzophenone in rats dosed orally, intravenously, or topically.

    PubMed

    el Dareer, S M; Kalin, J R; Tillery, K F; Hill, D L

    1986-01-01

    Administration to rats of oral doses of [14C]-2-hydroxy-4-methoxybenzophenone (HMB) in the range of 3.01-2570 mg/kg revealed that a dose-dependent elimination process was operative at the highest dose. Urinary excretion (63.9-72.9% of the dose in 72 h) was the major route for elimination of radioactivity. An intravenous dose (4.63 mg/kg) distributed rapidly throughout the body of rats and appeared in the urine in an amount (67.4%) similar to those for the oral doses. Rats absorbed large portions of doses of [14C]HMB administered topically, either as an ethanolic solution (50, 200, or 800 micrograms/rat) or formulated in a lotion (50 micrograms/rat). For rats with biliary cannulas, 36.6% of the radioactivity of an intravenous dose (4.46 mg/kg) appeared in the bile in 4 h; the initial half-life for biliary elimination was 40 min. In the bile, at least five radioactive components, none of which was intact HMB, were present. The two major components were glucuronides of HMB and demethylated HMB, and a third was probably a sulfate ester of hydroxylated HMB. In urine, there were nine radioactive components, two of which were unchanged HMB and its glucuronide.

  19. Clinical trial with Secnidazole in a single dose in Venezuelan children infected by Giardia intestinalis.

    PubMed

    Di Prisco, M C; Jiménez, J C; Rodríguez, N; Costa, V; Villamizar, J; Silvera, A; Carrillo, M; Lira, C; Zerpa, E; López, Y

    2000-09-01

    The aim of this work was to evaluate in an open, noncomparative study the use of secnidazole in oral suspension given to Venezuelan children infected with Giardia intestinalis, from a community in Carapita, a slum area in Caracas. Seventy children from 2 to 11 years old (38 males and 32 females) were treated with a single oral dose of secnidazole (30 mg/Kg of body weight), after clinical and parasitological evaluation to make the diagnosis of active giardiasis. The effectiveness of treatment was determined by clinical examination and parasitological evaluation of feces samples 15 days after treatment. The results showed 95% of clinical cure with a significant decrease of the frequency of gastrointestinal symptoms. The parasitological cure was 98%, there were 4 failures at the end of treatment. Side effects observed after treatment were of mild intensity, lasting only few hours. These results show that a simple dose of secnidazole in an oral suspension is an effective, safe and well tolerated treatment for giardiasis in children and that this drug may be used as a mass treatment in risk populations. PMID:11029834

  20. Neutral red uptake cytotoxicity tests for estimating starting doses for acute oral toxicity tests.

    PubMed

    Stokes, William S; Casati, Silvia; Strickland, Judy; Paris, Michael

    2008-05-01

    In vitro cytotoxicity assays can be used as alternative toxicity tests to reduce the total number of animals needed for acute oral toxicity tests. This unit describes two methods for determining the in vitro cytotoxicity of test substances using neutral red uptake (NRU) and using the in vitro data to determine starting doses for in vivo acute oral systemic toxicity tests, e.g., the up-and-down procedure or the acute toxic class method. The use of the NRU methods to determine starting doses for acute oral toxicity tests may reduce the number of animals required, and for relatively toxic substances, this approach may also reduce the number of animals that die or require humane euthanasia due to severe toxicity. An interlaboratory validation study has demonstrated that the methods are useful and reproducible for these purposes. Two standardized protocols provide details for performing NRU tests with rodent and human cells.

  1. Complete Protection against Pneumonic and Bubonic Plague after a Single Oral Vaccination

    PubMed Central

    Derbise, Anne; Hanada, Yuri; Khalifé, Manal; Carniel, Elisabeth; Demeure, Christian E.

    2015-01-01

    Background No efficient vaccine against plague is currently available. We previously showed that a genetically attenuated Yersinia pseudotuberculosis producing the Yersinia pestis F1 antigen was an efficient live oral vaccine against pneumonic plague. This candidate vaccine however failed to confer full protection against bubonic plague and did not produce F1 stably. Methodology/Principal Findings The caf operon encoding F1 was inserted into the chromosome of a genetically attenuated Y. pseudotuberculosis, yielding the VTnF1 strain, which stably produced the F1 capsule. Given orally to mice, VTnF1 persisted two weeks in the mouse gut and induced a high humoral response targeting both F1 and other Y. pestis antigens. The strong cellular response elicited was directed mostly against targets other than F1, but also against F1. It involved cells with a Th1—Th17 effector profile, producing IFNγ, IL-17, and IL-10. A single oral dose (108 CFU) of VTnF1 conferred 100% protection against pneumonic plague using a high-dose challenge (3,300 LD50) caused by the fully virulent Y. pestis CO92. Moreover, vaccination protected 100% of mice from bubonic plague caused by a challenge with 100 LD50 Y. pestis and 93% against a high-dose infection (10,000 LD50). Protection involved fast-acting mechanisms controlling Y. pestis spread out of the injection site, and the protection provided was long-lasting, with 93% and 50% of mice surviving bubonic and pneumonic plague respectively, six months after vaccination. Vaccinated mice also survived bubonic and pneumonic plague caused by a high-dose of non-encapsulated (F1-) Y. pestis. Significance VTnF1 is an easy-to-produce, genetically stable plague vaccine candidate, providing a highly efficient and long-lasting protection against both bubonic and pneumonic plague caused by wild type or un-encapsulated (F1-negative) Y. pestis. To our knowledge, VTnF1 is the only plague vaccine ever reported that could provide high and durable protection

  2. Single dose mebendazole therapy for soil-transmitted nematodes.

    PubMed

    Abadi, K

    1985-01-01

    Four hundred and fifty subjects were included in a study of the prevalence of soil-transmitted nematodes in Ujung Pandang, South-Sulawesi, Indonesia. Trichuriasis was the most prevalent infection (93.3%), followed by ascariasis (80.2%) and hookworm infection (19.5%). Among 156 subjects who were given 500 mg of mebendazole in a single dose, treatment resulted in cure rates of 93.4%, 77.6%, and 91.1%, and average egg-count reduction rates of 99.0%, 92.8%, and 98.3%, for ascariasis, trichuriasis, and hookworm infections, respectively. Mebendazole appeared to be equally effective against necatoriasis and ancylostomiasis. The drug was well tolerated and almost no side effects were observed. Single dose mebendazole treatment appears to be relatively inexpensive, convenient, and effective in mass treatment for the control of intestinal nematode infections, especially in highly infected communities.

  3. Oral and Conjunctival Exposure of Nonhuman Primates to Low Doses of Ebola Makona Virus

    PubMed Central

    Mire, Chad E.; Geisbert, Joan B.; Agans, Krystle N.; Deer, Daniel J.; Fenton, Karla A.; Geisbert, Thomas W.

    2016-01-01

    Nonhuman primate (NHP) models of Ebola virus (EBOV) infection primarily use parenteral or aerosol routes of exposure. Uniform lethality can be achieved in these models at low doses of EBOV (≤100 plaque-forming units [PFU]). Here, we exposed NHPs to low doses of EBOV (Makona strain) by the oral or conjunctival routes. Surprisingly, animals exposed to 10 PFU by either route showed no signs of disease. Exposure to 100 PFU resulted in illness and/or lethal infection. These results suggest that these more natural routes require higher doses of EBOV to produce disease or that there may be differences between Makona and historical strains. PMID:27284090

  4. Single-dose fentanyl sublingual spray for breakthrough cancer pain.

    PubMed

    Taylor, Donald R

    2013-01-01

    Breakthrough cancer pain (BTCP) is defined as a transient exacerbation of pain that arises in patients with otherwise controlled persistent pain. BTCP typically has a rapid onset and relatively short duration, but it causes a significant amount of physical and psychological distress for patients. Several rapid-onset fentanyl formulations have been introduced in the USA to replace traditional oral opioids for the treatment of BTCP: a transmucosal lozenge, a sublingual orally disintegrating tablet, a buccal tablet, a buccal soluble film, a pectin nasal spray and, the newest formulation to enter the market, a sublingual spray. This article reviews the six rapid-onset formulations of fentanyl approved in the USA for the management of BTCP with emphasis on describing the published literature on fentanyl sublingual spray. The different fentanyl formulations vary in pharmacokinetic properties and ease of use, but all have a rapid onset and a relatively short duration of analgesia. Fentanyl sublingual spray has demonstrated absorption within 5 minutes of administration, with fentanyl plasma concentrations increasing over the first 30 minutes and remaining elevated for 60-90 minutes in pharmacokinetic studies in healthy subjects. Fentanyl sublingual spray shows linear dose proportionality, and changes in the temperature or acidity of the oral cavity do not alter its pharmacokinetic properties. In patients with BTCP, statistically significant pain relief is measurable at 5 minutes after administration of fentanyl sublingual spray, when compared with placebo, with significant pain relief lasting at least 60 minutes after administration. Adverse events are typical of opioid treatment and are considered mild to moderate in intensity. In summary, fentanyl sublingual spray provides rapid onset of analgesia and is a tolerable and effective treatment for BTCP. PMID:23901300

  5. Single-dose fentanyl sublingual spray for breakthrough cancer pain

    PubMed Central

    Taylor, Donald R

    2013-01-01

    Breakthrough cancer pain (BTCP) is defined as a transient exacerbation of pain that arises in patients with otherwise controlled persistent pain. BTCP typically has a rapid onset and relatively short duration, but it causes a significant amount of physical and psychological distress for patients. Several rapid-onset fentanyl formulations have been introduced in the USA to replace traditional oral opioids for the treatment of BTCP: a transmucosal lozenge, a sublingual orally disintegrating tablet, a buccal tablet, a buccal soluble film, a pectin nasal spray and, the newest formulation to enter the market, a sublingual spray. This article reviews the six rapid-onset formulations of fentanyl approved in the USA for the management of BTCP with emphasis on describing the published literature on fentanyl sublingual spray. The different fentanyl formulations vary in pharmacokinetic properties and ease of use, but all have a rapid onset and a relatively short duration of analgesia. Fentanyl sublingual spray has demonstrated absorption within 5 minutes of administration, with fentanyl plasma concentrations increasing over the first 30 minutes and remaining elevated for 60–90 minutes in pharmacokinetic studies in healthy subjects. Fentanyl sublingual spray shows linear dose proportionality, and changes in the temperature or acidity of the oral cavity do not alter its pharmacokinetic properties. In patients with BTCP, statistically significant pain relief is measurable at 5 minutes after administration of fentanyl sublingual spray, when compared with placebo, with significant pain relief lasting at least 60 minutes after administration. Adverse events are typical of opioid treatment and are considered mild to moderate in intensity. In summary, fentanyl sublingual spray provides rapid onset of analgesia and is a tolerable and effective treatment for BTCP. PMID:23901300

  6. Radiation damage in single-particle cryo-electron microscopy: effects of dose and dose rate

    PubMed Central

    Karuppasamy, Manikandan; Karimi Nejadasl, Fatemeh; Vulovic, Milos; Koster, Abraham J.; Ravelli, Raimond B. G.

    2011-01-01

    combined with an improved understanding of the effects of dose and dose rate will aid single-particle cryo-electron microscopists to have better control of the outcome of their experiments. PMID:21525648

  7. Radiation damage in single-particle cryo-electron microscopy: effects of dose and dose rate.

    PubMed

    Karuppasamy, Manikandan; Karimi Nejadasl, Fatemeh; Vulovic, Milos; Koster, Abraham J; Ravelli, Raimond B G

    2011-05-01

    an improved understanding of the effects of dose and dose rate will aid single-particle cryo-electron microscopists to have better control of the outcome of their experiments. PMID:21525648

  8. Failure of antimony trioxide to induce micronuclei or chromosomal aberrations in rat bone-marrow after sub-chronic oral dosing.

    PubMed

    Kirkland, David; Whitwell, James; Deyo, James; Serex, Tessa

    2007-03-01

    Antimony trioxide (Sb2O3, CAS 1309-64-4) is widely used as a flame retardant synergist in a number of household products, as a fining agent in glass manufacture, and as a catalyst in the manufacture of various types of polyester plastics. It does not induce point mutations in bacteria or mammalian cells, but is able to induce chromosomal aberrations (CA) in cultured cells in vitro. Although no CA or micronuclei (MN) have been induced after acute oral dosing of mice, repeated oral dosing for 14 or 21 days resulted in increased CA in one report, but did not result in increased MN in another. In order to further investigate its in vivo genotoxicity, Sb2O3 was dosed orally to groups of rats for 21 days at 250, 500 and 1000 mg/kg day. There were no clinical signs of toxicity in the Sb2O3-exposed animals except for some reductions in body-weight gain in the top dose group. Toxicokinetic measurements in a separate study confirmed bone-marrow exposure, and at higher levels than would have been achieved by single oral dosing. Large numbers of cells were scored for CA (600 metaphases/sex group) and MN (12,000 PCE/sex group) but frequencies of CA or MN in Sb2O3-treated rats were very similar to controls, and not biologically or statistically different, at all doses. These results provide further indication that Sb2O3 is not genotoxic to the bone marrow of rodents after 21 days of oral administration at high doses close to the maximum tolerated dose. PMID:17174592

  9. Salbutamol Residues in Plasma, Urine and Hair of Heifers After a Single Dose and Throughout.

    PubMed

    Zhang, Kai; Liang, Xiaowei; Su, Chuanyou; Tang, Chaohua; Zhao, Qingyu; Zhang, Junmin; Meng, Qingshi

    2016-07-01

    The objective of this study was to evaluate the salbutamol residues in the plasma, urine and hair of heifers after a single dose. Three heifers were given a single oral dose of salbutamol hydrochloride (150 μg/kg bodyweight). The salbutamol concentrations were measured in the plasma, urine (before and after hydrolysis with β-glucuronidase/arylsulfatase) and hair samples with ultra-performance liquid chromatography-tandem mass spectrometry. In the unhydrolyzed samples, the peak concentrations of salbutamol occurred in the plasma and urine at 12 and 8 h after drug administration, respectively, but were below the limit of quantification (LOQ = 0.2 ng/mL) at 48 and 120 h after administration, respectively. However, in the hydrolyzed samples, the salbutamol concentration was 1.1 ng/mL in the plasma 72 h after its administration and 0.7 ng/mL in the urine 168 h after its administration. Thus, the concentrations of salbutamol were significantly higher in the hydrolyzed samples than that in the unhydrolyzed samples (P < 0.01). The concentrations of salbutamol in the black and white hair 24 h after its administration were 1.7 and 1.0 ng/g, respectively. These results indicate that hair may be a target tissue for detecting the misuse of salbutamol after a single dose and that the primary forms of salbutamol in the plasma and urine samples from heifers are its sulfate and glucuronide conjugates. PMID:27165803

  10. Penetration of Linezolid into Soft Tissues of Healthy Volunteers after Single and Multiple Doses

    PubMed Central

    Dehghanyar, Pejman; Bürger, Cornelia; Zeitlinger, Markus; Islinger, Florian; Kovar, Florian; Müller, Markus; Kloft, Charlotte; Joukhadar, Christian

    2005-01-01

    The present study tested the ability of linezolid to penetrate soft tissues in healthy volunteers. Ten healthy volunteers were subjected to linezolid drug intake at a dose of 600 mg twice a day for 3 to 5 days. The first dose was administered intravenously. All following doses were self-administered orally. The tissue penetration of linezolid was assessed by use of in vivo microdialysis. In the single-dose experiments the ratios of the area under the concentration-time curve from 0 to 8 h (AUC0-8) for tissue to the AUC0-8 for free plasma were 1.4 ± 0.3 (mean ± standard deviation) and 1.3 ± 0.4 for subcutaneous adipose and muscle tissue, respectively. After multiple doses, the corresponding mean ratios were 0.9 ± 0.2 and 1.0 ± 0.5, respectively. The ratios of the AUC from 0 to 24 h (AUC0-24) for free linezolid in tissues to the MIC were between 50 and 100 for target pathogens with MICs between 2 and 4 mg/liter. In conclusion, the present study showed that linezolid penetrates rapidly into the interstitial space fluid of subcutaneous adipose and skeletal muscle tissues in healthy volunteers. On the basis of pharmacokinetic-pharmacodynamic calculations, we suggest that linezolid concentrations in soft tissues can be considered sufficient to inhibit the growth of many clinically relevant bacteria. PMID:15917535

  11. Metabolite profiles of rats in repeated dose toxicological studies after oral and inhalative exposure.

    PubMed

    Fabian, E; Bordag, N; Herold, M; Kamp, H; Krennrich, G; Looser, R; Ma-Hock, L; Mellert, W; Montoya, G; Peter, E; Prokudin, A; Spitzer, M; Strauss, V; Walk, T; Zbranek, R; van Ravenzwaay, B

    2016-07-25

    The MetaMap(®)-Tox database contains plasma-metabolome and toxicity data of rats obtained from oral administration of 550 reference compounds following a standardized adapted OECD 407 protocol. Here, metabolic profiles for aniline (A), chloroform (CL), ethylbenzene (EB), 2-methoxyethanol (ME), N,N-dimethylformamide (DMF) and tetrahydrofurane (THF), dosed inhalatively for six hours/day, five days a week for 4 weeks were compared to oral dosing performed daily for 4 weeks. To investigate if the oral and inhalative metabolome would be comparable statistical analyses were performed. Best correlations for metabolome changes via both routes of exposure were observed for toxicants that induced profound metabolome changes. e.g. CL and ME. Liver and testes were correctly identified as target organs. In contrast, route of exposure dependent differences in metabolic profiles were noted for low profile strength e.g. female rats dosed inhalatively with A or THF. Taken together, the current investigations demonstrate that plasma metabolome changes are generally comparable for systemic effects after oral and inhalation exposure. Differences may result from kinetics and first pass effects. For compounds inducing only weak changes, the differences between both routes of exposure are visible in the metabolome.

  12. Disposition of 2-mercaptobenzothiazole and 2-mercaptobenzothiazole disulfide in rats dosed intravenously, orally, and topically and in guinea pigs dosed topically

    SciTech Connect

    el Dareer, S.M.; Kalin, J.R.; Tillery, K.F.; Hill, D.L.; Barnett, J.W. Jr. )

    1989-01-01

    To determine the metabolic disposition of (14C)-2-mercaptobenzothiazole (MBT) and (14C)-2-mercaptobenzothiazole disulfide (MBTS), male and female rats were dosed topically. Topical doses were 36.1 micrograms/animal for (14C)MBT and 33.6 micrograms/animal for (14C)MBTS. Although more MBT passed through the skin than MBTS and although, relative to rats, guinea pigs absorbed a greater percentage of the dose (33.4% compared to 16.1-17.5% of the MBT and 12.2% compared to 5.94-7.87% for MBTS), the disposition of radioactivity derived from the two compounds was similar. Washing of the skin removed more of the radioactivity from guinea pigs than from rats. For both sexes of rats dosed intravenously with (14C)MBT or (14C)MBTS, disposition of the compounds was similar. In 72 h, 90.9-101% of the dose appeared in the urine and 3.79-15.1% in the feces. At this time, a small portion of the administered radioactivity remained associated with erythrocytes. Oral dosing of rats for 14 d with unlabeled MBT prior to a single dose of (14C)MBT or with unlabeled MBTS prior to a single dose of (14C)MBTS (0.730 mg/kg). For both sexes, disposition of the compounds was similar. At 96 h after dosing, a small portion of the administered radioactivity remained associated with erythrocytes, most of which was bound to the membranes. For both compounds and sexes, 60.8-101% of the radioactivity administered appeared in the urine and 3.46-9.99% in the feces in 96 h. At the time, only trace amounts of radioactivity remained in tissues other than blood. Of these tissues, thyroid contained the highest concentration. In the urine, there was a detectable MBT or MBTS, but there were two metabolites, one of which was identified as a thioglucuronide derivative of MBT. The other was possibly a sulfonic acid derivative of MBT.

  13. Minimum Effective Dose of Cattle and Sheep BSE for Oral Sheep Infection

    PubMed Central

    McGovern, Gillian; Martin, Stuart; Jeffrey, Martin; Dexter, Glenda; Hawkins, Steve A. C.; Bellworthy, Sue J.; Thurston, Lisa; Algar, Lynne; González, Lorenzo

    2016-01-01

    The minimum dose required to cause infection of Romney and Suffolk sheep of the ARQ/ARQ or ARQ/ARR prion protein gene genotypes following oral inoculation with Romney or Suffolk a sheep Bovine spongiform encephalopathy (BSE)-derived or cattle BSE-derived agent was investigated using doses ranging from 0.0005g to 5g. ARQ/ARQ sheep which were methionine (M) / threonine (T) heterozygous or T/T homozygous at codon 112 of the Prnp gene, dosed ARQ/ARR sheep and undosed controls did not show any evidence of infection. Within groups of susceptible sheep, the minimum effective oral dose of BSE was found to be 0.05g, with higher attack rates following inoculation with the 5g dose. Surprisingly, this study found no effect of dose on survival time suggesting a possible lack of homogeneity within the inoculum. All clinical BSE cases showed PrPd accumulation in brain; however, following cattle BSE inoculation, LRS involvement within Romney recipients was found to be significantly lower than within the Suffolk sheep inoculated group which is in agreement with previous reports. PMID:26968011

  14. Minimum Effective Dose of Cattle and Sheep BSE for Oral Sheep Infection.

    PubMed

    McGovern, Gillian; Martin, Stuart; Jeffrey, Martin; Dexter, Glenda; Hawkins, Steve A C; Bellworthy, Sue J; Thurston, Lisa; Algar, Lynne; González, Lorenzo

    2016-01-01

    The minimum dose required to cause infection of Romney and Suffolk sheep of the ARQ/ARQ or ARQ/ARR prion protein gene genotypes following oral inoculation with Romney or Suffolk a sheep Bovine spongiform encephalopathy (BSE)-derived or cattle BSE-derived agent was investigated using doses ranging from 0.0005g to 5g. ARQ/ARQ sheep which were methionine (M) / threonine (T) heterozygous or T/T homozygous at codon 112 of the Prnp gene, dosed ARQ/ARR sheep and undosed controls did not show any evidence of infection. Within groups of susceptible sheep, the minimum effective oral dose of BSE was found to be 0.05g, with higher attack rates following inoculation with the 5g dose. Surprisingly, this study found no effect of dose on survival time suggesting a possible lack of homogeneity within the inoculum. All clinical BSE cases showed PrPd accumulation in brain; however, following cattle BSE inoculation, LRS involvement within Romney recipients was found to be significantly lower than within the Suffolk sheep inoculated group which is in agreement with previous reports. PMID:26968011

  15. Low dose oral iodized oil for control of iodine deficiency in children.

    PubMed

    Zimmermann, M; Adou, P; Torresani, T; Zeder, C; Hurrell, R

    2000-08-01

    In areas where iodized salt is not available, oral iodized oil is often used to correct I deficiency despite a lack of consensus on the optimal dose or duration of effect, particularly in children, a main target group. Annual doses ranging from 400 to 1000 mg have been advocated for school-age children. Because lower doses of iodized oil have been shown to be effective in treating I deficiency in adults, the aim of this study was to evaluate the efficacy and safety of a low dose of oral iodized oil in goitrous I-deficient children. Goitrous children (n 104, mean age 8.4 years, range 6-12 years, 47% female) received 0.4 ml oral iodized poppyseed-oil containing 200 mg I. Baseline measurements included I in spot urines (UI), serum thyroxine (T4), whole blood thyroid-stimulating hormone (TSH), and thyroid-gland volume using ultrasound. At 1, 5, 10, 15, 30 and 50 weeks post-intervention, UI, TSH and T4 were measured. At 10, 15, 30 and 50 weeks, thyroid-gland volume was remeasured. At 30 and 50 weeks the mean percentage change in thyroid volume from baseline was -35% and -41% respectively. The goitre rate fell to 38% at 30 weeks and 17% at 50 weeks. No child showed signs of I-induced hypo- or hyperthyroidism. UI remained significantly increased above baseline for the entire year (P < 0.001); the median UI at 50 weeks was 97 micrograms/l, at the World Health Organization cut-off value (100 micrograms/l) for I-deficiency disorders risk. In this group of goitrous children, an oral dose of 200 mg I as Lipiodol (Guerbert, Roissy CdG Cedex, France) was safe and effective for treating goitre and maintaining normal I status for at least 1 year.

  16. Low-dose oral interferon modulates expression of inflammatory and autoimmune genes in cattle.

    PubMed

    Mamber, Stephen W; Lins, Jeremy; Gurel, Volkan; Hutcheson, David P; Pinedo, Pablo; Bechtol, David; Krakowka, Steven; Fields-Henderson, Rachel; Cummins, Joseph M

    2016-04-01

    While the safety and efficacy profiles of orally administered bovine interferon (IFN) alpha have been documented, the mechanism(s) that result in clinical benefits remain elusive. One approach to delineating the molecular pathways of IFN efficacy is through the use of gene expression profiling technologies. In this proof-of-concept study, different (0, 50, 200 and 800 units) oral doses of natural bovine IFN (type I) were tested in cattle to determine if oral IFN altered the expression of genes that may be pivotal to the development of systemic resistance to viral infections such as foot-and-mouth disease (FMD). Oral IFN was administered twice: Time 0 and 8h later. Blood was collected at 0, 8 and 24h after the first IFN administration, and DNA isolated from peripheral blood mononuclear cells (PBMCs) was employed in quantitative polymerase chain reaction (qPCR) microarray assays. Within 8h, 50 and 200 units of oral IFN induced significant (P<0.05) changes in expression of 41 of 92 tested autoimmune and inflammatory response-associated genes. These data suggest that orally administered IFN is a viable approach for providing short-term antiviral immunity to livestock exposed to viruses such as FMD virus (FMDV) until such a time that an effective vaccine can be produced and distributed to producers. PMID:27032505

  17. Plasma bupivacaine levels following single dose intraarticular instillation for arthroscopy.

    PubMed

    Meinig, R P; Holtgrewe, J L; Wiedel, J D; Christie, D B; Kestin, K J

    1988-01-01

    Arthroscopy of the knee was performed using 30 ml single dose intraarticular instillations of 0.5% or 0.25% solutions of bupivacaine (Marcaine). A total of 18 patients (mean age, 34 years), divided into two groups, participated in this study. Venous plasma levels were measured at 0, 10, 20, 30, 45, 60, 90, 120, and 240 minute intervals following a single instillation into the knee joint. All patients had suspected traumatic internal derangement of the knee. Electrocardiogram tracings, blood pressure, and neurologic assessment were monitored at each venous sampling interval or more often if clinically indicated. The type and amount of supplemental anesthesia were also recorded. None of our 18 patients required a general anesthetic because of pain although the following procedures were performed: meniscectomy, plica release, abrasion chondroplasty, loose body retrieval, and limited meniscal repair. A new methodology for the measurement of plasma bupivacaine using the gas chromatograph mass spectrometer is described. Monitoring specific molecular mass fragments allows the measurement of picogram per milliliter levels of bupivacaine. The highest peak plasma concentration occurred 20 minutes after instillation of 30 ml of 0.5% bupivacaine. The 625 +/- 225 ng/ml level was well below the 2,500 to 4,000 ng/ml reported to elicit early subjective CNS symptoms of bupivacaine toxicity. Thus, a single dose intraarticular instillation of 30 ml 0.5% or 0.25% bupivacaine is convenient, efficacious, and pharmacologically safe for routine clinical arthroscopy.

  18. Clinical evaluation of a single daily dose of phenylpropanolamine in the treatment of urethral sphincter mechanism incompetence in the bitch

    PubMed Central

    Claeys, Stéphanie; Rustichelli, Frederico; Noël, Stéphanie; Hamaide, Annick

    2011-01-01

    The objective of this retrospective study was to determine the efficacy of a single daily oral dose of phenylpropanolamine (PPA) in the treatment of urethral sphincter mechanism incompetence (USMI) in bitches. Nine bitches diagnosed with USMI were treated with a single daily dose [1.5 mg/kg body weight (BW)] of PPA for at least 1 month. Urethral pressure profiles (UPP) were performed in 7 dogs before treatment and repeated in 4 of them after treatment. Treatment with PPA resulted in long-term continence in 8/9 bitches. One dog did not respond to PPA and was treated surgically later. Recheck UPPs showed a significant increase in maximal urethral closure pressure in the 4 bitches after treatment with PPA compared to before treatment. In conclusion, long-term continence can be achieved in bitches affected with USMI after administration of a single daily dose of PPA (1.5 mg/kg BW). PMID:22043069

  19. Risk Factors and Dose-Effect Relationship for Mandibular Osteoradionecrosis in Oral and Oropharyngeal Cancer Patients

    SciTech Connect

    Lee, Ik Jae; Koom, Woong Sub; Lee, Chang Geol; Kim, Yong Bae; Yoo, Sei Whan; Keum, Ki Chang; Kim, Gwi Eon; Choi, Eun Chang; Cha, In Ho

    2009-11-15

    Purpose: To analyze risk factors and the dose-effect relationship for osteoradionecrosis (ORN) of the mandible after radiotherapy of oral and oropharyngeal cancers. Materials and Methods: One-hundred ninety-eight patients with oral (45%) and oropharyngeal cancer (55%) who had received external radiotherapy between 1990 and 2000 were retrospectively reviewed. All patients had a dental evaluation before radiotherapy. The median radiation dose was 60 Gy (range, 16-75 Gy), and the median biologically effective dose for late effects (BED{sub late}) in bone was 114 Gy{sub 2} (range, 30-167 Gy{sub 2}). Results: The frequency of ORN was 13 patients (6.6%). Among patients with mandibular surgery, eight had ORN at the surgical site. Among patients without mandibular surgery, five patients had ORN on the molar area of the mandible. The median time to ORN was 22 months (range, 1-69 months). Univariate analysis revealed that mandibular surgery and Co-60 were significant risk factors for ORN (p = 0.01 and 0.04, respectively). In multivariate analysis, mandibular surgery was the most important factor (p = 0.001). High radiation doses over BED 102.6 Gy{sub 2} (conventional dose of 54 Gy at 1.8 Gy/fraction) were also a significant factor for ORN (p = 0.008) and showed a positive dose-effect relationship in logistic regression (p = 0.04) for patients who had undergone mandibular surgery. Conclusions: Mandibular surgery was the most significant risk factor for ORN of mandible in oral and oropharyngeal cancers patients. A BED of 102.6 Gy{sub 2} or higher to the mandible also significantly increases the risk of ORN.

  20. Effect of dose size on the pharmacokinetics of oral hydrocortisone suspension.

    PubMed

    Toothaker, R D; Craig, W A; Welling, P G

    1982-10-01

    The pharmacokinetics of hydrocortisone were examined following single doses of 5-, 10-, 20-, and 40-mg hydrocortisone suspensions to healthy male volunteers. Endogenous hydrocortisone was suppressed by giving 2 mg of dexamethasone the night before hydrocortisone administration. Plasma samples obtained serially for 12 hr after hydrocortisone administration were assayed by reversed-phase high-pressure liquid chromatography using a fixed-wavelength (254 nm) UV absorbance detector. Drug absorption was rapid, with mean maximum plasma hydrocortisone concentrations occurring within 60 min of dosing. Subsequent drug elimination was monophasic with mean elimination half-lives increasing from 1.2 hr for the 5-mg dose to 1.7 hr for the 40-mg dose. Increase in AUC and Cmax with increasing dose were linear but not directly proportional to dose size. This was attributed to dose-dependent absorption or to loss of drug the first-pass through the liver.

  1. Oral Dosing of Chemical Indicators for In Vivo Monitoring of Ca2+ Dynamics in Insect Muscle

    PubMed Central

    Ferdinandus; Arai, Satoshi; Ishiwata, Shin’ichi; Suzuki, Madoka; Sato, Hirotaka

    2015-01-01

    This paper proposes a remarkably facile staining protocol to visually investigate dynamic physiological events in insect tissues. We attempted to monitor Ca2+ dynamics during contraction of electrically stimulated living muscle. Advances in circuit miniaturization and insect neuromuscular physiology have enabled the hybridization of living insects and man-made electronic components, such as microcomputers, the result of which has been often referred as a Living Machine, Biohybrid, or Cyborg Insect. In order for Cyborg Insects to be of practical use, electrical stimulation parameters need to be optimized to induce desired muscle response (motor action) and minimize the damage in the muscle due to the electrical stimuli. Staining tissues and organs as well as measuring the dynamics of chemicals of interest in muscle should be conducted to quantitatively and systematically evaluate the effect of various stimulation parameters on the muscle response. However, existing staining processes require invasive surgery and/or arduous procedures using genetically encoded sensors. In this study, we developed a non-invasive and remarkably facile method for staining, in which chemical indicators can be orally administered (oral dosing). A chemical Ca2+ indicator was orally introduced into an insect of interest via food containing the chemical indicator and the indicator diffused from the insect digestion system to the target muscle tissue. We found that there was a positive relationship between the fluorescence intensity of the indicator and the frequency of electrical stimulation which indicates the orally dosed indicator successfully monitored Ca2+ dynamics in the muscle tissue. This oral dosing method has a potential to globally stain tissues including neurons, and investigating various physiological events in insects. PMID:25590329

  2. Oral dosing of chemical indicators for in vivo monitoring of Ca2+ dynamics in insect muscle.

    PubMed

    Ferdinandus; Arai, Satoshi; Ishiwata, Shin'ichi; Suzuki, Madoka; Sato, Hirotaka

    2015-01-01

    This paper proposes a remarkably facile staining protocol to visually investigate dynamic physiological events in insect tissues. We attempted to monitor Ca2+ dynamics during contraction of electrically stimulated living muscle. Advances in circuit miniaturization and insect neuromuscular physiology have enabled the hybridization of living insects and man-made electronic components, such as microcomputers, the result of which has been often referred as a Living Machine, Biohybrid, or Cyborg Insect. In order for Cyborg Insects to be of practical use, electrical stimulation parameters need to be optimized to induce desired muscle response (motor action) and minimize the damage in the muscle due to the electrical stimuli. Staining tissues and organs as well as measuring the dynamics of chemicals of interest in muscle should be conducted to quantitatively and systematically evaluate the effect of various stimulation parameters on the muscle response. However, existing staining processes require invasive surgery and/or arduous procedures using genetically encoded sensors. In this study, we developed a non-invasive and remarkably facile method for staining, in which chemical indicators can be orally administered (oral dosing). A chemical Ca2+ indicator was orally introduced into an insect of interest via food containing the chemical indicator and the indicator diffused from the insect digestion system to the target muscle tissue. We found that there was a positive relationship between the fluorescence intensity of the indicator and the frequency of electrical stimulation which indicates the orally dosed indicator successfully monitored Ca2+ dynamics in the muscle tissue. This oral dosing method has a potential to globally stain tissues including neurons, and investigating various physiological events in insects. PMID:25590329

  3. Toxicokinetics and toxicodynamics of gonyautoxins after an oral toxin dose in cats.

    PubMed

    Andrinolo, Darío; Iglesias, Verónica; García, Carlos; Lagos, Néstor

    2002-06-01

    Although the action of Gonyautoxins (GTXs) and Saxitoxin (STX) mechanisms is well known at the molecular level, there are still many unresolved questions associated with the intoxication syndrome in mammals. For example, how are these toxins absorbed in the digestive system? Where are they absorbed? What is the absorption rate? What is the maximal concentration in plasma (C(max)) and the time taken to reach this C(max) (T(max)) in the case of oral toxin administration? These questions are addressed in this paper, which describes an experimental design which allowed us to follow the toxicokinetics and toxicodynamics of GTX 2/3 epimers poisoning in vivo, when an oral dose of toxin was administered to an anaesthetized cat permanently coupled to an artificial ventilator. The GTX 2/3 epimers was orally administered with a dose of 70 microg/kg, then urine and blood samples were collected during a 5 h experimental period. The toxins were quantified using a post column derivatisation high performance liquid chromatography method. Procedure of extraction, clean up and detection of GTX 2/3 epimers are described. The arterial pressure of the cats was continuously monitored. The GTX 2/3 epimers oral dose was completely absorbed at intestinal level. This dose was sufficient to decrease arterial pressure and to produce death within the experimental time. However, with the intravenous (i.v.) administration of 2.5 microg/min kg of dobutamine, hemodynamic parameters were restored which allowed the animal to overcome the cardiovascular shock. The renal clearance of GTX 2/3 epimers measured in the cats was 4.6 ml/min kg, indicating that like STX, in cats with normal cardiovascular parameters and diuresis, the GTX 2/3 excretion mainly involves glomerular filtration. Oral doses of 35 microg/kg of GTX 2/3 epimers and plasma level of 36 ng/ml are lethal limits for cats. This is the first report that shows the effects of the GTX 2/3 epimers at different plasmatic levels and their

  4. No change in spontaneous behavior of rats after acute oral doses of aspartame, phenylalanine, and tyrosine.

    PubMed

    Mullenix, P J; Tassinari, M S; Schunior, A; Kernan, W J

    1991-04-01

    Spontaneous behavior subsequent to acute oral administration of high doses of aspartame, phenylalanine, or tyrosine was analyzed using a computer pattern recognition system. Sprague-Dawley male rats (250-300 g) were dosed orally with aspartame (500 or 1000 mg/kg), phenylalanine (281 or 562 mg/kg), or tyrosine (309 or 618 mg/kg), and their behavior was analyzed 1 hr after dosing. The computer pattern recognition system recorded and classified 13 different behavioral acts performed by the animals during the first 15-min exploration of a novel environment. Three measures that provide independent information concerning motor output from the central nervous system were taken: the number of behavioral initiations, total time, and time structure. These results were compared with the effects induced by d-amphetamine. Plasma concentrations of phenylalanine and tyrosine were determined from blood samples taken immediately after behavioral examination. Data analysis revealed that these doses of aspartame, phenylalanine, and tyrosine did not induce any significant changes in spontaneous behavior. Unlike low doses of amphetamine and despite high plasma concentrations of phenylalanine and tyrosine, no behavioral alteration was detected by the computer pattern recognition system. Absence of behavioral changes in this study using an objective analysis of behavior raises questions concerning the relationship between amino acid precursor loading and purported anecdotal changes in behavior following aspartame administration.

  5. Comparative single dose and steady-state pharmacokinetics of bevantolol in young and elderly subjects.

    PubMed

    Selen, A; Kinkel, A W; Darke, A C; Greene, D S; Welling, P G

    1986-01-01

    The pharmacokinetics of bevantolol were examined following single and repeated oral doses to young and elderly volunteers. Following administration of a single 200-mg bevantolol tablet mean maximum plasma bevantolol concentrations in young and elderly subjects were 1690 ng/ml and 1810 ng/ml, respectively. Maximum bevantolol concentrations occurred approximately 1.1 h postdose in both young and elderly subjects. There were no significant differences in mean steady state bevantolol concentrations on Day 14 between young and elderly subjects. However, disproportionate increases in Cmax, and in AUC, but not in tmax values were observed between Days 1 and 14. On Days 1 and 14, most young and elderly subjects exhibited monoexponential decline in bevantolol plasma concentrations after absorption phase. In those subjects Day 14 elimination half-lives in young and elderly were 1.9 and 2.2 h, respectively. In subjects who exhibited biexponential decline in bevantolol, an age effect in elimination became apparent, on Day 14 elimination half-lives were 5.7 and 11.2 h in young and elderly subjects, respectively. Bevantolol Metabolite III concentrations were observed in plasma of some subjects during the first 6 h after dosing. At steady-state AUC (0-ldc) values for the metabolite were less than 2% those of bevantolol. Bevantolol plasma levels accumulate to a small extent with repeated 200 mg daily doses. This is probably due to the contribution of a late and more persistent terminal elimination phase that was discernable in only certain individuals.

  6. Use of dose-dependent absorption into target tissues to more accurately predict cancer risk at low oral doses of hexavalent chromium.

    PubMed

    Haney, J

    2015-02-01

    The mouse dose at the lowest water concentration used in the National Toxicology Program hexavalent chromium (CrVI) drinking water study (NTP, 2008) is about 74,500 times higher than the approximate human dose corresponding to the 35-city geometric mean reported in EWG (2010) and over 1000 times higher than that based on the highest reported tap water concentration. With experimental and environmental doses differing greatly, it is a regulatory challenge to extrapolate high-dose results to environmental doses orders of magnitude lower in a meaningful and toxicologically predictive manner. This seems particularly true for the low-dose extrapolation of results for oral CrVI-induced carcinogenesis since dose-dependent differences in the dose fraction absorbed by mouse target tissues are apparent (Kirman et al., 2012). These data can be used for a straightforward adjustment of the USEPA (2010) draft oral slope factor (SFo) to be more predictive of risk at environmentally-relevant doses. More specifically, the evaluation of observed and modeled differences in the fraction of dose absorbed by target tissues at the point-of-departure for the draft SFo calculation versus lower doses suggests that the draft SFo be divided by a dose-specific adjustment factor of at least an order of magnitude to be less over-predictive of risk at more environmentally-relevant doses.

  7. Effective dose equivalent to the operator in intra-oral dental radiography

    SciTech Connect

    de Haan, R.A.; van Aken, J. )

    1990-08-01

    The effective dose equivalent to the operator in intra-oral dental radiography has been determined. The exposure from a bitewing radiograph and periapical views of the left maxillary incisors and first molar was measured at nine heights and 16 positions, all 1 m from the patient. The effective dose equivalent was determined using data from ICRP 51 (International Commission on Radiological Protection: Data for Use in Protection Against External Radiation). The values presented are related to an exposure of 1 C kg-1 (3876 R) measured free in air at the tube-end. They thus constitute ratios which are not influenced by the sensitivity of the film or other detector used and form standard tables which permit the calculation of the effective dose equivalent in clinical situations.

  8. Long-Term High-dose Oral Morphine in Phantom Limb Pain with No Addiction Risk

    PubMed Central

    Kumar, Vinod; Garg, Rakesh; Bharati, Sachidanand Jee; Gupta, Nishkarsh; Bhatanagar, Sushma; Mishra, Seema; Balhara, Yatan Pal Singh

    2015-01-01

    Chronic phantom limb pain (PLP) is a type of neuropathic pain, which is located in the missing/amputated limb. Phantom pain is difficult to treat as the exact basis of pain mechanism is still unknown. Various methods of treatment for PLP have been described, including pharmacological (NSAIDs, opioids, antiepileptic, antidepressants) and non-pharmacological (TENS, sympathectomy, deep brain stimulation and motor cortex stimulation). Opioids are used for the treatment of neuropathic pain and dose of opioid is determined based on its effect and thus there is no defined ceiling dose for opioids. We report a case where a patient receiving high-dose oral morphine for chronic cancer pain did not demonstrate signs of addiction. PMID:25709194

  9. Development of a chronic noncancer oral reference dose and drinking water screening level for sulfolane using benchmark dose modeling.

    PubMed

    Thompson, Chad M; Gaylor, David W; Tachovsky, J Andrew; Perry, Camarie; Carakostas, Michael C; Haws, Laurie C

    2013-12-01

    Sulfolane is a widely used industrial solvent that is often used for gas treatment (sour gas sweetening; hydrogen sulfide removal from shale and coal processes, etc.), and in the manufacture of polymers and electronics, and may be found in pharmaceuticals as a residual solvent used in the manufacturing processes. Sulfolane is considered a high production volume chemical with worldwide production around 18 000-36 000 tons per year. Given that sulfolane has been detected as a contaminant in groundwater, an important potential route of exposure is tap water ingestion. Because there are currently no federal drinking water standards for sulfolane in the USA, we developed a noncancer oral reference dose (RfD) based on benchmark dose modeling, as well as a tap water screening value that is protective of ingestion. Review of the available literature suggests that sulfolane is not likely to be mutagenic, clastogenic or carcinogenic, or pose reproductive or developmental health risks except perhaps at very high exposure concentrations. RfD values derived using benchmark dose modeling were 0.01-0.04 mg kg(-1) per day, although modeling of developmental endpoints resulted in higher values, approximately 0.4 mg kg(-1) per day. The lowest, most conservative, RfD of 0.01 mg kg(-1) per day was based on reduced white blood cell counts in female rats. This RfD was used to develop a tap water screening level that is protective of ingestion, viz. 365 µg l(-1). It is anticipated that these values, along with the hazard identification and dose-response modeling described herein, should be informative for risk assessors and regulators interested in setting health-protective drinking water guideline values for sulfolane.

  10. Effect of repeated oral therapeutic doses of methylphenidate on food intake and growth rate in rats.

    PubMed

    Alam, Nausheen; Najam, Rahila

    2015-01-01

    Central nervous system stimulants are known to produce anorexia. Previous data suggest that methylphenidate can have variable effects on caloric intake and growth rate. A dose-response study was performed to monitor caloric intake, liquid intake and growth rate in rats following repeated administration of human oral therapeutic doses 2 mg/kg/day, 5mg/kg/day and 8mg/kg/day of methylphenidate. We found that food intake and water intake, increased in all weeks and at all doses used in the study. Growth rate increased more at higher dose (8mg/kg/day) and at low dose (2mg/kg/day) of methylphenidate in 1(st) and 2(nd) week whereas more decreased by the above doses in 3(rd) week, suggesting that food stimulation leads to initial increase in growth rate but long term administration of methylphenidate attenuate growth rate that is not due to modulation of appetite but may be due to anxiety and increased activity produce by stimulants. A possible role of DA, 5HT receptors in modulation of appetite and anxiety is discussed.

  11. Implications of dose-dependent target tissue absorption for linear and non-linear/threshold approaches in development of a cancer-based oral toxicity factor for hexavalent chromium.

    PubMed

    Haney, J

    2015-07-01

    Dose-dependent changes in target tissue absorption have important implications for determining the most defensible approach for developing a cancer-based oral toxicity factor for hexavalent chromium (CrVI). For example, mouse target tissue absorption per unit dose is an estimated 10-fold lower at the CrVI dose corresponding to the federal maximum contaminant level (MCL) than at the USEPA draft oral slope factor (SFo) point of departure dose. This decreasing target tissue absorption as doses decrease to lower, more environmentally-relevant doses is inconsistent with linear low-dose extrapolation. The shape of the dose-response curve accounting for this toxicokinetic phenomenon would clearly be non-linear. Furthermore, these dose-dependent differences in absorption indicate that the magnitude of risk overestimation by a linear low-dose extrapolation approach (e.g., SFo) increases and is likely to span one or perhaps more orders of magnitude as it is used to predict risk at progressively lower, more environmentally-relevant doses. An additional apparent implication is that no single SFo can reliably predict risk across potential environmental doses (e.g., doses corresponding to water concentrations⩽the federal MCL). A non-linear approach, consistent with available mode of action data, is most scientifically defensible for derivation of an oral toxicity factor for CrVI-induced carcinogenesis.

  12. Single dose testosterone administration reduces loss chasing in healthy females.

    PubMed

    Wu, Yin; Liu, Jinting; Qu, Lujing; Eisenegger, Christoph; Clark, Luke; Zhou, Xiaolin

    2016-09-01

    Testosterone has been linked to modulation of impulsivity and risky choice, potentially mediated by changes in reward or punishment sensitivity. This study investigated the effect of testosterone on risk-taking and the adjustment of risk-taking on trials following a gain or a loss. Loss chasing is operationalized herein as the propensity to recover losses by increasing risky choice. Healthy female participants (n=26) received a single-dose of 0.5mg sublingual testosterone in a double-blind, placebo-controlled crossover design. At 240min post-administration, participants performed a gambling task with a high and a low risk option. In the placebo condition, participants were more likely to choose the high risk option following losses compared to wins. This effect was abolished on the testosterone session. Ignoring prior outcomes, no overall changes in risk-taking were observed. Our data indicate that testosterone affects human decision-making via diminishing sensitivity to punishment. PMID:27236486

  13. Methyl Selenocysteine: single-dose pharmacokinetics in men

    PubMed Central

    Marshall, James R.; Ip, Clement; Romano, Karen; Fetterly, Gerald; Fakih, Marwan; Jovanovic, Borko; Perloff, Marjorie; Crowell, James; Davis, Warren; French-Christy, Renee; Dew, Alexander; Coomes, Margerie; Bergan, Raymond

    2011-01-01

    The recently published report of the SELECT evaluation of selenium and vitamin E provided strong evidence that selenium 200mcg/day in the form of selenomethionine does not protect selenium-replete men against prostate or any other cancer. This appears to refute the result of the much smaller Nutritional Prevention of Cancer (NPC) trial of selenium. Since SELECT did not test the NPC agent, is possible that the difference between the two trials stems partly from the use of different agents: selenomethionine in SELECT, selenized yeast in the NPC trial. One of the organic selenium forms suspected of having strong chemopreventive effects, and which may have been present in the NPC agent, is methyl selenocysteine. This study characterizes the single-dose pharmacokinetics of methyl selenocysteine. PMID:21846796

  14. Effective, single-dose treatment or porcine cysticercosis with oxfendazole.

    PubMed

    Gonzales, A E; Garcia, H H; Gilman, R H; Gavidia, C M; Tsang, V C; Bernal, T; Falcon, N; Romero, M; Lopez-Urbina, M T

    1996-04-01

    The pig is a vital link in the transmission cycle of Taenia solium, the cestode responsible for human-porcine cysticercosis. Infected pigs also represent an important source of economic loss to farmers in developing countries. Past efforts to find an adequate therapeutic regimen to treat this parasite disease in swine have failed because of low efficacy, high cost, side effects, or the need for multiple doses. In this randomized, no treatment-controlled study, the efficacy and safety of oxfendazole and praziquantel for the treatment of porcine cysticercosis were evaluated in 16 naturally infected pigs. Four groups of four pigs were treated with oxfendazole, praziquantel, oxfendazole plus praziquantel, or untreated. The pigs were humanely killed 12 weeks post-treatment, the number of cyst was counted, and parasite viability was assessed by cyst evagination. No detectable side effects were seen in any of the pigs. Praziquantel treatment alone appeared to reduce the number of cysts, but did not decrease the viability of the remaining parasites. Treatment with oxfendazole alone or oxfendazole plus praziquantel killed all of the parasites, and left only microcalcifications in the meat. Oxfendazole provides, for the first time, a practical, effective, inexpensive, and single-dose therapy for porcine cysticercosis.

  15. Single-dose cefuroxime axetil in the treatment of uncomplicated gonorrhea: a controlled trial.

    PubMed

    Reichman, R C; Nolte, F S; Wolinsky, S M; Greisberger, C A; Trupei, M A; Nitzkin, J

    1985-01-01

    One hundred eighty-four patients were enrolled in a randomized study that evaluated the efficacy and toxicity of a single dose of orally administered cefuroxine axetil in the treatment of men and women with uncomplicated gonorrhea. Sixty-two patients received cefuroxine axetil alone, 62 received cefuroxine axetil and probenecid, and 60 received amoxicillin plus probenecid. Cure rates in the three groups were 98%, 98%, 96%, respectively. Only 2% of patients who received cefuroxine axetil alone complained of nausea, as compared with 11% of those who received a regimen that contained probenecid (P less than .05). The results show that cefuroxime axetil is effective and nontoxic in the treatment of uncomplicated gonococcal infections in adults.

  16. PHARMACOKINETIC PROPERTIES OF A SINGLE ADMINISTRATION OF ORAL GABAPENTIN IN THE GREAT HORNED OWL (BUBO VIRGINIANUS).

    PubMed

    Yaw, Taylor J; Zaffarano, Bianca A; Gall, Andrew; Olds, June E; Wulf, Larry; Papastavros, Efthimia; Coetzee, Johann F

    2015-09-01

    Gabapentin (1-[aminomethyl] cyclohexane acetic acid) is a γ-aminobutyric acid analogue that has been shown to be efficacious for neuropathic pain control in humans. Plasma gabapentin concentrations >2 μg/ml are considered effective in treating epilepsy in humans and are suggested to provide analgesia for neuropathic pain. This study investigated the pharmacokinetics of a single oral dose of gabapentin suspension (11 mg/kg) in great horned owls ( Bubo virginianus ). Plasma gabapentin concentrations were determined in six healthy birds for 48 hr using high-performance liquid chromatography with mass spectrometric detection. Plasma gabapentin concentrations were estimated by noncompartmental pharmacokinetic analysis. The harmonic mean (±SD) maximum concentration (Cmax), time to maximum concentration (Tmax), and elimination half-life (tv2λZ) for gabapentin (11 mg/kg) were 6.17±0.83 μg/ml, 51.43±5.66 min, and 264.60±69.35 min, respectively. In this study, plasma gabapentin concentrations were maintained above 2 μg/ml for 528 min (8.8 hr), suggesting that gabapentin administered orally every 8 hr may be appropriate in great horned owls.

  17. PHARMACOKINETIC PROPERTIES OF A SINGLE ADMINISTRATION OF ORAL GABAPENTIN IN THE GREAT HORNED OWL (BUBO VIRGINIANUS).

    PubMed

    Yaw, Taylor J; Zaffarano, Bianca A; Gall, Andrew; Olds, June E; Wulf, Larry; Papastavros, Efthimia; Coetzee, Johann F

    2015-09-01

    Gabapentin (1-[aminomethyl] cyclohexane acetic acid) is a γ-aminobutyric acid analogue that has been shown to be efficacious for neuropathic pain control in humans. Plasma gabapentin concentrations >2 μg/ml are considered effective in treating epilepsy in humans and are suggested to provide analgesia for neuropathic pain. This study investigated the pharmacokinetics of a single oral dose of gabapentin suspension (11 mg/kg) in great horned owls ( Bubo virginianus ). Plasma gabapentin concentrations were determined in six healthy birds for 48 hr using high-performance liquid chromatography with mass spectrometric detection. Plasma gabapentin concentrations were estimated by noncompartmental pharmacokinetic analysis. The harmonic mean (±SD) maximum concentration (Cmax), time to maximum concentration (Tmax), and elimination half-life (tv2λZ) for gabapentin (11 mg/kg) were 6.17±0.83 μg/ml, 51.43±5.66 min, and 264.60±69.35 min, respectively. In this study, plasma gabapentin concentrations were maintained above 2 μg/ml for 528 min (8.8 hr), suggesting that gabapentin administered orally every 8 hr may be appropriate in great horned owls. PMID:26352959

  18. Evaluation of human pharmacokinetics, therapeutic dose and exposure predictions using marketed oral drugs.

    PubMed

    McGinnity, D F; Collington, J; Austin, R P; Riley, R J

    2007-06-01

    In this article approaches to predict human pharmacokinetics (PK) are discussed and the capability of the exemplified methodologies to estimate individual PK parameters and therapeutic dose for a set of marketed oral drugs has been assessed. For a set of 63 drugs where the minimum efficacious concentration (MEC) and human PK were known, the clinical dose was shown to be well predicted or in some cases over-estimated using a simple one-compartment oral PK model. For a subset of these drugs, in vitro potency against the primary human targets was gathered, and compared to the observed MEC. When corrected for plasma protein binding, the MEC of the majority of compounds was < or=3 fold over the respective in vitro target potency value. A series of in vitro and in vivo experiments were conducted to predict the human PK parameters. Metabolic clearance was generally predicted well from human hepatocytes. Interestingly, for this compound set, allometry or glomerular filtration rate (GFR) ratio methods appeared to be applicable for renal CL even where CL(renal) > GFR. For approximately 90% of compounds studied, the predicted CL using in vitro-in vivo (IVIV) extrapolation together with a CL(renal) estimate, where appropriate, was within 2-fold of that observed clinically. Encouragingly volume of distribution at steady state (V(ss)) estimated in preclinical species (rat and dog) when corrected for plasma protein binding, predicted human V(ss) successfully on the majority of occasions--73% of compounds within 2-fold. In this laboratory, absorption estimated from oral rat PK studies was lower than the observed human absorption for most drugs, even when solubility and permeability appeared not to be limiting. Preliminary data indicate absorption in the dog may be more representative of human for compounds absorbed via the transcellular pathway. Using predicted PK and MEC values estimated from in vitro potency assays there was a good correlation between predicted and observed dose

  19. Single high-dose vitamin D at birth corrects vitamin D deficiency in infants in Mexico.

    PubMed

    Moodley, Amaran; Spector, Stephen A

    2015-05-01

    This study examined the prevalence of vitamin D deficiency in mothers and infants in Tijuana, Mexico and determined the effect of a single oral dose of 50,000 IU vitamin D3 at birth on 25-hydroxyvitamin D (25[OH]D) levels during infancy. Healthy infants were randomized to receive vitamin D3 or placebo at birth. At birth 23% of infants were vitamin D deficient and 77% had vitamin D insufficiency (mean 25[OH]D level 18.9 ng/ml); 10% of mothers were vitamin D deficient and 61% were insufficient. Infants receiving vitamin D3 had higher 25(OH)D levels at two months (N = 29; 33.9 versus 24.2 ng/ml) and six months (N = 21; 36.5 versus 27.4 ng/ml). Exclusively breastfed infants had lower 25(OH)D levels at two months (14.9 versus 33.4 ng/ml). Vitamin D deficiency is common in infants and mothers in Tijuana, Mexico. A single dose of vitamin D3 at birth was safe and significantly increased 25(OH)D levels during infancy.

  20. Effect of Single Dose Administration of Methylsulfonylmethane on Oxidative Stress Following Acute Exhaustive Exercise

    PubMed Central

    Nakhostin-Roohi, Babak; Niknam, Zahra; Vaezi, Nasrin; Mohammadi, Sadollah; Bohlooli, Shahab

    2013-01-01

    Methylsulfonylmethane (MSM) is a sulfur-containing compound commonly found in diet and known to reduce oxidative stress. This trial was conducted to determine whether single dose supplementation with MSM attenuates post-exercise oxidative stress in healthy untrained young men. Sixteen untrained men volunteered for this study. Participants were randomized in a double-blind placebo-controlled fashion into 2 groups: Methylsulfonylmethane (MSM) (n = 8) and placebo (n = 8). The participants took supplementation or placebo before running on treadmill for 45 min at 75% VO2max. The MSM supplementation was prepared in water as 100 mg/ kg body weight. The placebo group received water. Serum Malondealdehyde (MDA), uric acid, bilirubin, protein carbonyl (PC) and plasma vitamin E levels were determined as the markers of oxidative stress. Plasma GSH (reduced Glutathione) and total antioxidant capacity (TAC) were measured as markers of plasma antioxidant system. MSM supplementation successfully lowered serum PC 2 and 24 h after exercise. Plasma TAC in MSM group was higher at 24 h after exercise. Serum level of uric acid and bilirubin were significantly low immediately after exercise in MSM supplemented group. There was no significant difference between groups in terms of plasma GSH level. These results complement earlier studies showing anti-oxidant effect of MSM and suggest that single dose oral supplementation with MSM lowers exercise induced oxidative stress in healthy untrained young men, but is not adequate to significantly affect plasma GSH level. PMID:24523764

  1. Single-dose metronidazole clears Opalina sp. from juvenile Bufo woodhousii.

    PubMed

    Nickol, Devin R; Tufts, Danielle M

    2013-06-01

    Protozoans of the family Opalinidae are intestinal commensals in amphibians. To test the hypothesis that these organisms are susceptible to the antiprotozoal antibiotic metronidazole, we randomly assigned 60 juvenile Woodhouse's toads ( Bufo woodhousii ) to receive a single oral dose of metronidazole or water. In pilot trials, the prevalence of opalinids in untreated members of this population was over 70%. One-third of the study population was dissected at each of 3 time points: 18 hr, 1 wk, and 2 wk post-treatment. An examiner blinded to the toad's treatment history determined the presence or absence of opalinids using a dissecting microscope. Opalinids were found in 3/10 toads in the treatment group and 9/10 in the control group after 18 hr (P < 0.02), in none of the treatment group and 8/10 in the control group after 1 wk (P < 0.001), and in none of the treatment group and 10/10 in the control group after 2 wk (P < 0.0001). These results suggest that a single-dose of metronidazole quickly and reliably clears opalinids from juvenile Woodhouse's toads with no evidence of short-term recurrence. The treatment was well tolerated, with no apparent morbidity and no mortality in either group. Future exploration of opalinid-related host fitness consequences may be facilitated by this simple method of developing a protozoan-free host population. PMID:23339344

  2. Effects of oral contrast on dose in abdominopelvic computed tomography with pure iterative reconstruction

    PubMed Central

    Murphy, Kevin P; Healy, Liam J; Crush, Lee; Twomey, Maria; Moloney, Fiachra; Sexton, Sylvia; O’Connor, Owen J; Maher, Michael M

    2016-01-01

    AIM To assess the effect of neutral (NC) and positive (PC) oral contrast use on patient dose in low-dose abdominal computed tomography (CT). METHODS Low-dose clinically indicated CTs were performed on 79 Crohn’s patients (35 = PC, 1 L 2% gastrografin; 44 = NC, 1.5 L polyethylene glycol). Scanner settings for both acquisitions were identical apart from 25 s difference in intravenous contrast timing. Body mass index (BMI), scan-ranges, dose-length product and size-specific dose estimated were recorded. Data was reconstructed with pure model-based iterative reconstruction. Image quality was objectively and subjectively analysed. Data analysis was performed with Statistical Package for Social Scientists. RESULTS Higher doses were seen in neutral contrast CTs (107.60 ± 78.7 mGy.cm, 2.47 ± 1.21 mGy vs 85.65 ± 58.2 mGy.cm, 2.18 ± 0.96 mGy). The difference was significant in 2 of 4 BMI groups and in those that had both NC and PC investigations. Image-quality assessment yielded 6952 datapoints. NC image quality was significantly superior (P < 0.001) (objective noise, objective signal to noise ratio, subjective spatial resolution, subjective contrast resolution, diagnostic acceptability) at all levels. NC bowel distension was significantly (P < 0.001) superior. CONCLUSION The use of polyethylene glycol as a neutral OC agent leads to higher radiation doses than standard positive contrast studies, in low dose abdominal CT imaging. This is possibly related to the osmotic effect of the agent resulting in larger intraluminal fluid volumes and resultant increased overall beam attenuation. PMID:27721943

  3. Population Pharmacokinetics and Dose Optimization of Mycophenolic Acid in HCT Recipients Receiving Oral Mycophenolate Mofetil

    PubMed Central

    Li, H; Mager, D E; Sandmaier, B M; Maloney, D G; Bemer, M J; McCune, J S

    2012-01-01

    We sought to create a population pharmacokinetic model for total mycophenolic acid (MPA), to study the effects of different covariates on MPA pharmacokinetics, to create a limited sampling schedule (LSS) to characterize MPA exposure (i.e., area under the curve or AUC) with maximum a posteriori Bayesian estimation, and to simulate an optimized dosing scheme for allogeneic hematopoietic cell transplantation (HCT) recipients. 4,496 MPA concentration-time points from 408 HCT recipients were analyzed retrospectively using a nonlinear mixed effects modeling approach. MPA pharmacokinetics was characterized with a two-compartment model with first-order elimination and a time-lagged first-order absorption process. Concomitant cyclosporine and serum albumin were significant covariates. The median MPA clearance and volume of the central compartment were 24.2 L/hr and 36.4 L, respectively, for a 70 kg patient receiving tacrolimus with a serum albumin of 3.4 g/dL. Dosing simulations indicated that higher oral MMF doses are needed with concomitant cyclosporine, which increases MPA clearance by 33.8%. The optimal LSS was immediately before and at 0.25, 1.25, 2, and 4hr after oral MMF administration. MPA AUC in an individual HCT recipient can be accurately estimated using a five-sample LSS and maximum a posteriori Bayesian estimation. PMID:23382105

  4. Population pharmacokinetics and dose optimization of mycophenolic acid in HCT recipients receiving oral mycophenolate mofetil.

    PubMed

    Li, H; Mager, D E; Sandmaier, B M; Maloney, D G; Bemer, M J; McCune, J S

    2013-04-01

    We sought to create a population pharmacokinetic model for total mycophenolic acid (MPA), to study the effects of different covariates on MPA pharmacokinetics, to create a limited sampling schedule (LSS) to characterize MPA exposure (i.e., area under the curve or AUC) with maximum a posteriori Bayesian estimation, and to simulate an optimized dosing scheme for allogeneic hematopoietic cell transplantation (HCT) recipients. Four thousand four hundred ninety-six MPA concentration-time points from 408 HCT recipients were analyzed retrospectively using a nonlinear mixed effects modeling approach. MPA pharmacokinetics was characterized with a two-compartment model with first-order elimination and a time-lagged first-order absorption process. Concomitant cyclosporine and serum albumin were significant covariates. The median MPA clearance (CL) and volume of the central compartment were 24.2 L/hour and 36.4 L, respectively, for a 70 kg patient receiving tacrolimus with a serum albumin of 3.4 g/dL. Dosing simulations indicated that higher oral MMF doses are needed with concomitant cyclosporine, which increases MPA CL by 33.8%. The optimal LSS was immediately before and at 0.25 hours, 1.25 hours, 2 hours, and 4 hours after oral mycophenolate mofetil administration. MPA AUC in an individual HCT recipient can be accurately estimated using a five-sample LSS and maximum a posteriori Bayesian estimation.

  5. Low dose oral cannabinoid therapy reduces progression of atherosclerosis in mice.

    PubMed

    Steffens, Sabine; Veillard, Niels R; Arnaud, Claire; Pelli, Graziano; Burger, Fabienne; Staub, Christian; Karsak, Meliha; Zimmer, Andreas; Frossard, Jean-Louis; Mach, François

    2005-04-01

    Atherosclerosis is a chronic inflammatory disease, and is the primary cause of heart disease and stroke in Western countries. Derivatives of cannabinoids such as delta-9-tetrahydrocannabinol (THC) modulate immune functions and therefore have potential for the treatment of inflammatory diseases. We investigated the effects of THC in a murine model of established atherosclerosis. Oral administration of THC (1 mg kg(-1) per day) resulted in significant inhibition of disease progression. This effective dose is lower than the dose usually associated with psychotropic effects of THC. Furthermore, we detected the CB2 receptor (the main cannabinoid receptor expressed on immune cells) in both human and mouse atherosclerotic plaques. Lymphoid cells isolated from THC-treated mice showed diminished proliferation capacity and decreased interferon-gamma secretion. Macrophage chemotaxis, which is a crucial step for the development of atherosclerosis, was also inhibited in vitro by THC. All these effects were completely blocked by a specific CB2 receptor antagonist. Our data demonstrate that oral treatment with a low dose of THC inhibits atherosclerosis progression in the apolipoprotein E knockout mouse model, through pleiotropic immunomodulatory effects on lymphoid and myeloid cells. Thus, THC or cannabinoids with activity at the CB2 receptor may be valuable targets for treating atherosclerosis.

  6. Prescription and consumption of solid oral drugs dispensed as unitary doses in a third level hospital

    PubMed Central

    Calderón-Guzmán, David; Juárez-Olguín, Hugo; Hernández-García, Ernestina; Medina-Andrade, Alejandro; Juarez Tapia, Belen

    2015-01-01

    Background: The knowledge about the pattern of prescription and consumption of solid oral drugs dispensed as unitary doses (UD) in Mexico is sparing. Purpose: The aim of this study was to describe the pattern of prescription and consumption of solid oral drugs dispensed as unitary doses (UD) in a third level private hospital of Mexico. A retrospective study of a 60-month period (from 2007 to 2011) was carried out to know the pattern of drugs dispensed as UD in a third level hospital. Results: Among the principal drugs consumed were analgesic, antihypertensive, antibiotic, anti-inflammatory, antiepileptic, and diuretics. The dispensation of drugs per year was as follows: 181 drugs with 85,167 UD in 2007; 199 with 90,519 UD in 2008; 193 with 101,479 UD in 2009; 195 with 100,798 UD in 2010; and 198 with 103,913 UD in 2011. Conclusion: The findings confirmed that prescription and consumption of unitary doses in the hospitalization service increased, and revealed the extensive use of analgesics as the principal prescribed drug in this kind of hospital. PMID:27013914

  7. Population pharmacokinetics and dose optimization of mycophenolic acid in HCT recipients receiving oral mycophenolate mofetil.

    PubMed

    Li, H; Mager, D E; Sandmaier, B M; Maloney, D G; Bemer, M J; McCune, J S

    2013-04-01

    We sought to create a population pharmacokinetic model for total mycophenolic acid (MPA), to study the effects of different covariates on MPA pharmacokinetics, to create a limited sampling schedule (LSS) to characterize MPA exposure (i.e., area under the curve or AUC) with maximum a posteriori Bayesian estimation, and to simulate an optimized dosing scheme for allogeneic hematopoietic cell transplantation (HCT) recipients. Four thousand four hundred ninety-six MPA concentration-time points from 408 HCT recipients were analyzed retrospectively using a nonlinear mixed effects modeling approach. MPA pharmacokinetics was characterized with a two-compartment model with first-order elimination and a time-lagged first-order absorption process. Concomitant cyclosporine and serum albumin were significant covariates. The median MPA clearance (CL) and volume of the central compartment were 24.2 L/hour and 36.4 L, respectively, for a 70 kg patient receiving tacrolimus with a serum albumin of 3.4 g/dL. Dosing simulations indicated that higher oral MMF doses are needed with concomitant cyclosporine, which increases MPA CL by 33.8%. The optimal LSS was immediately before and at 0.25 hours, 1.25 hours, 2 hours, and 4 hours after oral mycophenolate mofetil administration. MPA AUC in an individual HCT recipient can be accurately estimated using a five-sample LSS and maximum a posteriori Bayesian estimation. PMID:23382105

  8. Single-Dose Pharmacokinetics and Safety of Ziprasidone in Children and Adolescents

    ERIC Educational Resources Information Center

    Sallee, Floyd R.; Miceli, Jeffrey J.; Tensfeldt, Thomas; Robarge, Lisa; Wilner, Keith; Patel, Nick C.

    2006-01-01

    Objective: The purpose of this study was to provide single-dose pharmacokinetic, safety, and tolerability data for ziprasidone in youths with tic disorder, for comparison to adult studies to discern whether ziprasidone pediatric dosing could be modeled from adult data. Method: A single-dose, open-label study of ziprasidone was conducted in youths…

  9. Evaluation of body composition during low-dose estrogen oral contraceptives treatment.

    PubMed

    Franchini, M; Caruso, C; Nigrelli, S; Poggiali, C

    1995-01-01

    The effect of two low-dose oral contraceptives (OCs) on weight and body composition was evaluated in 80 family planning clinic outpatients 18-43 years of age. These women were randomly assigned to receive OCs containing either 20 mcg ethinyl estradiol and 150 mcg desogestrel or 30 mcg ethinyl estradiol and 75 mcg gestodene. 20 IUD users served as controls. Anthropometric measurements and body composition (estimated by Bioelectrical Impedance Analysis) were assessed at baseline and after 6 and 12 months of OC use. In all three groups, body weight, body mass index, total body water, and body cellular mass remained unchanged during the 12-month study period. These findings confirm that the new low-dose OCs have no significant effects on body weight or composition.

  10. Consensus Guidelines for Oral Dosing of Primarily Renally Cleared Medications in Older Adults

    PubMed Central

    Hanlon, Joseph T.; Aspinall, Sherrie L.; Semla, Todd P.; Weisbord, Steven D.; Fried, Linda F.; Good, C. Bernie; Fine, Michael J.; Stone, Roslyn A.; Pugh, Mary Jo V.; Rossi, Michelle I.; Handler, Steven M.

    2008-01-01

    Objectives To establish consensus oral dosing guidelines for primarily renally cleared medications prescribed for older adults. Design Two-round modified Delphi Survey. Participants Expert panel of 11 geriatric clinical pharmacists. Measurements After a comprehensive literature search and review by the investigative group of 6 physicians (2 from general internal medicine, 2 nephrologists, 2 geriatricians), 45 dosing recommendations for 30 medications at various levels of renal function were created. The expert panel rated their agreement with each of these 45 dosing recommendations using a 5-point Likert scale (1= strongly disagree to 5=strongly agree). Recommendation-specific means and 95% confidence intervals were estimated. Consensus was defined as a lower 95% confidence limit of >4.0 for the recommendation –specific mean score. Results The response rate was 81.8% (9/11) for the first round. All respondents that completed the first round also completed the second round. The expert panel reached consensus on 26 recommendations involving 18 (60%) medications. For 10 medications (chlorpropamide, colchicine, cotrimoxazole, glyburide, meperidine, nitrofurantoin, probenecid, propoxyphene, spironolactone, and triamterene), the consensus recommendation was not to use the medication in older adults below a specified level of renal function (e.g., creatinine clearance < 30 ml/min). For the remaining 8 medications (acyclovir, amantadine, ciprofloxacin, gabapentin, memantine, ranitidine, rimantadine, and valacyclovir), specific recommendations for dose reduction or interval extension were made. Conclusion An expert panel of geriatric clinical pharmacists was able to reach consensus agreement on a number of oral medications that are primarily renally cleared. PMID:19170784

  11. Pharmacokinetics of R 82913 in AIDS patients: a phase I dose-finding study of oral administration compared with intravenous infusion.

    PubMed Central

    De Wit, S; Hermans, P; Sommereijns, B; O'Doherty, E; Westenborghs, R; van de Velde, V; Cauwenbergh, G F; Clumeck, N

    1992-01-01

    The pharmacokinetics of oral administration of R 82913, or tetrahydroimidazol [4,5,1-jk]-benzodiazepin-2(1H)-one or -thione (TIBO), was compared with those of intravenous administration in five AIDS patients. TIBO was administered as a single daily 1-h infusion of 100 mg for 29 days and orally as a single daily dose for 14 days with three consecutive regimens of 100, 200, and 100 mg with probenecid (1 g) daily. Each cycle was followed by a wash-out period. Oral bioavailability of TIBO appears to be low and is not improved by the adjunction of probenecid. Trough levels obtained with oral administration systematically remained far below the 90% inhibitory concentration of TIBO against human immunodeficiency virus type 1 (HIV-1). Tolerance of TIBO was excellent. No clinical efficacy could be demonstrated. p24 antigenemia decreased significantly in one patient under intravenous therapy. TIBO derivatives are promising anti-HIV-1 agents in vitro, but improvement of oral bioavailability is needed before implementation of long-term efficacy and tolerability studies. Moreover, rapid emergence of resistance, which has been recently documented, constitutes a major problem with most nonnucleoside reverse transcriptase inhibitors. PMID:1482134

  12. Serial Myocardial Imaging after a Single Dose of Thallium-201.

    PubMed

    Kamata, Takahiko; Kawasaki, Tatsuya; Kamitani, Tadaaki; Sugihara, Hiroki

    2014-01-01

    Although thallium-201 exercise scintigraphy has been established for the detection of myocardial ischemia and viability, little is known regarding the myocardial thallium-201 kinetics during angioplasty. Herein, we report a 77-year-old man with angina pectoris, in whom serial myocardial imaging after a single dose of thallium-201 was helpful in identifying not only the culprit lesion and myocardial viability, but also the dynamic changes in myocardial perfusion during angioplasty. Thallium-201 images after exercise showed a perfusion defect in the inferior wall, with a trivial redistribution 3 hours after the exercise and a marked improvement 24 hours later. Coronary angiography, performed 27 hours after exercise scintigraphy, showed severe stenosis in the right coronary artery. Guidewire crossing of the lesion interrupted the antegrade flow, which was restored after balloon dilation and stent implantation. Thallium-201 images, 2 hours after angioplasty (i.e., 30 hours after exercise), showed a decreased tracer uptake in the inferior wall, which improved the next day (i.e., 48 hours after exercise). Cardiac biomarkers were negative in the clinical course.

  13. Intrapulmonary pharmacokinetics of azithromycin in healthy volunteers given five oral doses.

    PubMed Central

    Olsen, K M; San Pedro, G; Gann, L P; Gubbins, P O; Halinski, D M; Campbell, G D

    1996-01-01

    The intrapulmonary pharmacokinetics of oral azithromycin were studied in 25 healthy volunteers, each of whom received an initial dose of 500 mg and then 250 mg once daily for four additional doses. Bronchoscopy, bronchoalveolar lavage, and venipuncture were performed 4, 28, 76, 124, 172, 244, 340, and 508 h after the first dose was administered. Azithromycin concentrations in epithelial lining fluid (ELF), alveolar macrophages, peripheral blood monocytes, and serum were measured by high-performance liquid chromatography. Azithromycin was extensively concentrated in cells and ELF. Drug concentrations in AMs (peak mean +/- standard deviation, 464 +/- 65 micrograms/ml) exceeded 80 micrograms/ml up to 508 h (21 days) following the first dose, while concentrations in PBMs (peak, 124 +/- 28 micrograms/ml) exceeded 20 micrograms/ml up to 340 h (14 days). Azithromycin concentrations in ELF peaked at 124 h (3.12 +/- 0.93 micrograms/ml) and were detectable up to 172 h (7 days), when they were 20 times the concurrent serum concentrations. Although the clinical significance of antibiotic concentrations in these compartments is nuclear, the sustained lung tissue penetration and extensive phagocytic accumulation demonstrated in this study support the proven efficacy of azithromycin administered on a 5-day dosage schedule in the treatment of extracellular or intracellular pulmonary infections. PMID:8913469

  14. Dose-dependent immunohistochemical and ultrastructural changes after oral methylphenidate administration in rat heart tissue.

    PubMed

    Take, G; Bahcelioglu, M; Oktem, H; Tunc, E; Gözil, R; Erdogan, D; Calguner, E; Helvacioglu, F; Giray, S G; Elmas, C

    2008-08-01

    Methylphenidate, more commonly known as Ritalin, is a piperidine derivative and is the drug most often used to treat attention deficit/hyperactivity disorder, one of the most common behavioural disorders of children and young adults. Our aims were to investigate dose-dependent immunohistochemical D2 expression and ultrastructural changes of the rat heart tissue, and to demonstrate possible toxicity of the long-term and high dose use of the methylphenidate. In this study, 27 female pre-pubertal Wistar albino rats, divided into three different dose groups (5, 10 and 20 mg/kg) and their control groups, were used. They were treated orally with methylphenidate dissolved in saline solution for 5 days/week during 3 months. At the end of the third month, after perfusion fixation, left ventricle of cardiac tissue was removed. Paraffin, semi-thin and thin sections were collected and immunohistochemical, terminal deoxynucleotidyl transferase-mediated Dig-dUTP nick end labelling assay and ultrastructural studies were performed. In conclusion, we believe that Ritalin is dose-related affecting dopaminergic system to increase heart rhythm and contraction. Thus, this drug may cause degenerative ultrastructural changes in mitochondrial path.

  15. High doses of oral folate and sublingual vitamin B12 in dialysis patients with hyperhomocysteinemia

    PubMed Central

    Naseri, Mitra; Sarvari, Gholam-Reza; Esmaeeli, Mohammad; Azarfar, Anoush; Rasouli, Zahra; Moeenolroayaa, Giti; Jahanshahi, Shohre; Farhadi, Simin; Heydari, Zohreh; Sagheb-Taghipoor, Narges

    2016-01-01

    Introduction: Folic acid and vitamin B12, alone or in combination have been used to reduce homocysteine (Hcy) levels in dialysis patients. Objectives: We aimed to assess the efficacy of high doses of oral folate and vitamin B12 in reducing plasma Hcy levels after a 12-week treatment. Patients and Methods: Thirty-two dialysis patients aged 10-324 months screened for hyperhomocysteinuria. Then cases with hyperhomocysteinemia received oral folate 10 mg/day with sublingual methylcobalamin 1 mg/day for 12 weeks. In pre- and post-intervention phases plasma Hcy concentration, serum folate, and vitamin B12 levels were measured. Changes in plasma Hcy, serum folate, and vitamin B12 concentrations were analyzed by paired t tests, and P values < 0.05 were considered significant. Results: Eighteen (56.2%) patients had hyperhomocysteinuria. Vitamin B12 and folate levels were normal or high in all cases. Two patients were lost due to transplant or irregular drugs consumption. Plasma Hcy levels were reduced in all, and reached normal values in 50%. A statistically significant differences between first Hcy levels with levels after intervention was found (95% CI, 5.1–8.9, P = 0.0001). Conclusion: Oral folate 10 mg/day in combination with sublingual vitamin B12, 1 mg/day can be considered as a favorable treatment for hyperhomocysteinemia in dialysis patients. PMID:27689109

  16. High doses of oral folate and sublingual vitamin B12 in dialysis patients with hyperhomocysteinemia

    PubMed Central

    Naseri, Mitra; Sarvari, Gholam-Reza; Esmaeeli, Mohammad; Azarfar, Anoush; Rasouli, Zahra; Moeenolroayaa, Giti; Jahanshahi, Shohre; Farhadi, Simin; Heydari, Zohreh; Sagheb-Taghipoor, Narges

    2016-01-01

    Introduction: Folic acid and vitamin B12, alone or in combination have been used to reduce homocysteine (Hcy) levels in dialysis patients. Objectives: We aimed to assess the efficacy of high doses of oral folate and vitamin B12 in reducing plasma Hcy levels after a 12-week treatment. Patients and Methods: Thirty-two dialysis patients aged 10-324 months screened for hyperhomocysteinuria. Then cases with hyperhomocysteinemia received oral folate 10 mg/day with sublingual methylcobalamin 1 mg/day for 12 weeks. In pre- and post-intervention phases plasma Hcy concentration, serum folate, and vitamin B12 levels were measured. Changes in plasma Hcy, serum folate, and vitamin B12 concentrations were analyzed by paired t tests, and P values < 0.05 were considered significant. Results: Eighteen (56.2%) patients had hyperhomocysteinuria. Vitamin B12 and folate levels were normal or high in all cases. Two patients were lost due to transplant or irregular drugs consumption. Plasma Hcy levels were reduced in all, and reached normal values in 50%. A statistically significant differences between first Hcy levels with levels after intervention was found (95% CI, 5.1–8.9, P = 0.0001). Conclusion: Oral folate 10 mg/day in combination with sublingual vitamin B12, 1 mg/day can be considered as a favorable treatment for hyperhomocysteinemia in dialysis patients.

  17. Comparison of Vaginal and Oral Doses of Misoprostol for Labour Induction in Post-Term Pregnancies

    PubMed Central

    Rezaie, Masomeh; Farhadifar, Fariba; Nayebi, Morteza

    2016-01-01

    Introduction Considering maternal complications, it is preferred to induce labour after 40 weeks. Labour induction is a procedure used to stimulate uterine contractions during pregnancy before the beginning of the labour. Aim The aim of this study was to compare oral misoprostol with vaginal misoprostol for induction of labour in post-term pregnancies. Materials and Methods This double blind clinical-trial study was performed on 180 post-term pregnant women who were admitted to the labour ward of Besat Hospital Sanandaj, Iran in 2013-2014. Participants were equally divided into three groups using block randomization method. The induction was performed for the first group with 100 μg of oral misoprostol, for the second group with 50 μg of oral misoprostol, and for the third group with 25 μg of vaginal misoprostol. Vaginal examination and FHR was done before repeating each dose to determine Bishop Score. Induction time with misoprostol to the start of uterine contractions, induction time to delivery, and mode of delivery, systolic tachycardia, hyper stimulation and fetal outcomes were studied as well. Results First minute Apgar scores and medication dosage of the study groups were significantly different (p=0.0001). But labour induction, induction frequency, mode of delivery, complications, and 5 minutes Apgar score in the groups had no significant difference (p>0.05). The risk of fetal distress and neonatal hospitalization of the groups were statistically significant (p=0. 02). There was no significant difference between the three groups in terms of mean time interval from the administration of misoprostol to the start of uterine contractions (labour induction), the time interval from the start of uterine contractions to delivery and taking misoprostol to delivery. From the administration of misoprostol to start of the uterine contractions the mean difference between time intervals in the three groups were not statistically significant. Conclusion Based on our

  18. Dose-dependent pharmacokinetics and brain penetration of rufinamide following intravenous and oral administration to rats.

    PubMed

    Gáll, Zsolt; Vancea, Szende; Szilágyi, Tibor; Gáll, Orsolya; Kolcsár, Melinda

    2015-02-20

    Rufinamide is a third-generation antiepileptic drug, approved recently as an orphan drug for the treatment of Lennox-Gastaut syndrome. Although extensive research was conducted, its pharmacokinetics in rats was not described. This work addresses that area by describing in a rapid pharmacokinetic study the main pharmacokinetic properties of rufinamide at three different doses of 1 mg/kg body weight (bw), 5 mg/kg bw, and 20 mg/kg bw. Furthermore, total brain concentrations of the drug were determined in order to characterize its brain-to-plasma partition coefficient. Adult Wistar male rats, weighing 200-450 g, were administered rufinamide by intravenous and oral routes. Rufinamide concentrations from plasma samples and brain tissue homogenate were determined using a liquid chromatography-mass spectrometric method and pharmacokinetic parameters were calculated. The mean half-life was between 7 and 13 h, depending on route of administration--intravenously administered drug was eliminated faster than orally administered drug. Mean (S.E.M.) total plasma clearance was 84.01 ± 3.80 ml/h/kg for intravenous administration, while the apparent plasma clearance for oral administration was 95.52 ± 39.45 ml/h/kg. The mean (S.E.M.) maximum plasma concentration reached after oral administration of 1 mg/kg bw and 5 mg/kg bw was 0.89 ± 0.09 μg/ml and 3.188 ± 0.71 μg/ml, respectively. The median (range) time to reach maximum plasma concentration (t(max)) was 4 (2-8)h. Mean (S.E.M.) brain-to-plasma concentration ratio of rufinamide was 0.514 ± 0.036, consistent with the brain-to-plasma ratio calculated from the area under curves (AUC(0-t)) of 0.441 ± 0.047. No influence of dose, route of administration, or post-dosing time was observed on brain-to-plasma ratio. PMID:25530452

  19. The impact of dosing interval in a novel tandem oral dosing strategy: enhancing the exposure of low solubility drug candidates in a preclinical setting.

    PubMed

    Chiang, Po-Chang; South, Sarah A; Wene, Steve P

    2011-01-01

    In drug discovery, time and resource constraints necessitate increasingly early decision making to accelerate or stop preclinical programs. Early discovery drug candidates may be potent inhibitors of new targets, but all too often exhibit poor pharmaceutical or pharmacokinetic properties that limit the in vivo exposure. Low solubility of a drug candidate often leads to poor oral bioavailability and poor dose linearity. This issue is more significant for efficacy and target safety studies where high drug exposures are desired. When solubility issues are confronted, enabling formulations are often required to improve the exposure. However, this approach often requires a substantial and lengthy investment to develop the formulation. Previously, we introduced a gastrointestinal (GI) transit time-based novel oral tandem dosing strategy that enhanced in vivo exposures in rats. In this study, a refined time interval versus dose theory was tested. The resulting in vivo exposures based on altering frequency and doses were compared, and significant impacts were found.

  20. Synthetic ozonide drug candidate OZ439 offers new hope for a single-dose cure of uncomplicated malaria

    PubMed Central

    Charman, Susan A.; Arbe-Barnes, Sarah; Bathurst, Ian C.; Brun, Reto; Campbell, Michael; Charman, William N.; Chiu, Francis C. K.; Chollet, Jacques; Craft, J. Carl; Creek, Darren J.; Dong, Yuxiang; Matile, Hugues; Maurer, Melanie; Morizzi, Julia; Nguyen, Tien; Papastogiannidis, Petros; Scheurer, Christian; Shackleford, David M.; Sriraghavan, Kamaraj; Stingelin, Lukas; Tang, Yuanqing; Urwyler, Heinrich; Wang, Xiaofang; White, Karen L.; Wittlin, Sergio; Zhou, Lin; Vennerstrom, Jonathan L.

    2011-01-01

    Ozonide OZ439 is a synthetic peroxide antimalarial drug candidate designed to provide a single-dose oral cure in humans. OZ439 has successfully completed Phase I clinical trials, where it was shown to be safe at doses up to 1,600 mg and is currently undergoing Phase IIa trials in malaria patients. Herein, we describe the discovery of OZ439 and the exceptional antimalarial and pharmacokinetic properties that led to its selection as a clinical drug development candidate. In vitro, OZ439 is fast-acting against all asexual erythrocytic Plasmodium falciparum stages with IC50 values comparable to those for the clinically used artemisinin derivatives. Unlike all other synthetic peroxides and semisynthetic artemisinin derivatives, OZ439 completely cures Plasmodium berghei-infected mice with a single oral dose of 20 mg/kg and exhibits prophylactic activity superior to that of the benchmark chemoprophylactic agent, mefloquine. Compared with other peroxide-containing antimalarial agents, such as the artemisinin derivatives and the first-generation ozonide OZ277, OZ439 exhibits a substantial increase in the pharmacokinetic half-life and blood concentration versus time profile in three preclinical species. The outstanding efficacy and prolonged blood concentrations of OZ439 are the result of a design strategy that stabilizes the intrinsically unstable pharmacophoric peroxide bond, thereby reducing clearance yet maintaining the necessary Fe(II)-reactivity to elicit parasite death. PMID:21300861

  1. Effects of Age, Sex, and Obesity on the Single-Dose Pharmacokinetics of Omarigliptin in Healthy Subjects.

    PubMed

    Addy, Carol; Tatosian, Daniel A; Glasgow, Xiaoli S; Iii, Isaias Noel Gendrano; Sisk, Christine McCrary; Kauh, Eunkyung A; Stoch, S Aubrey; Wagner, John A

    2016-09-01

    Omarigliptin is being developed as a potent, once-weekly, oral dipeptidyl peptidase-4 inhibitor for the treatment of type 2 diabetes. This double-blind, randomized, placebo-controlled study evaluated the effects of age, sex, and obesity on the pharmacokinetics of omarigliptin in healthy subjects. A single oral dose of omarigliptin 10 mg (n = 6/panel) or placebo (n = 2/panel) was administered in the fasted state to elderly nonobese men and women, young obese (30 ≤ body mass index [BMI] ≤ 35 kg/m(2) ) men and women, and young nonobese women of nonchildbearing potential. Plasma was collected at selected postdose times for evaluation of omarigliptin concentrations. Pharmacokinetic parameters were compared with historical data from a previously-conducted single-dose study in young, healthy, nonobese men. There were no clinically significant differences in omarigliptin AUC0-∞ , the primary pharmacokinetic parameter for assessing efficacy and safety, based on age, sex, or BMI (pooled nonobese elderly versus pooled nonobese young, young nonobese female versus young nonobese male, and pooled young obese versus pooled young nonobese). There were no serious adverse events or hypoglycemic events attributable to omarigliptin administration. Demographic factors and BMI had no meaningful effect on omarigliptin pharmacokinetics, suggesting that dose adjustment based on age, sex, or obesity is not required. PMID:27627193

  2. Synthetic ozonide drug candidate OZ439 offers new hope for a single-dose cure of uncomplicated malaria.

    PubMed

    Charman, Susan A; Arbe-Barnes, Sarah; Bathurst, Ian C; Brun, Reto; Campbell, Michael; Charman, William N; Chiu, Francis C K; Chollet, Jacques; Craft, J Carl; Creek, Darren J; Dong, Yuxiang; Matile, Hugues; Maurer, Melanie; Morizzi, Julia; Nguyen, Tien; Papastogiannidis, Petros; Scheurer, Christian; Shackleford, David M; Sriraghavan, Kamaraj; Stingelin, Lukas; Tang, Yuanqing; Urwyler, Heinrich; Wang, Xiaofang; White, Karen L; Wittlin, Sergio; Zhou, Lin; Vennerstrom, Jonathan L

    2011-03-15

    Ozonide OZ439 is a synthetic peroxide antimalarial drug candidate designed to provide a single-dose oral cure in humans. OZ439 has successfully completed Phase I clinical trials, where it was shown to be safe at doses up to 1,600 mg and is currently undergoing Phase IIa trials in malaria patients. Herein, we describe the discovery of OZ439 and the exceptional antimalarial and pharmacokinetic properties that led to its selection as a clinical drug development candidate. In vitro, OZ439 is fast-acting against all asexual erythrocytic Plasmodium falciparum stages with IC(50) values comparable to those for the clinically used artemisinin derivatives. Unlike all other synthetic peroxides and semisynthetic artemisinin derivatives, OZ439 completely cures Plasmodium berghei-infected mice with a single oral dose of 20 mg/kg and exhibits prophylactic activity superior to that of the benchmark chemoprophylactic agent, mefloquine. Compared with other peroxide-containing antimalarial agents, such as the artemisinin derivatives and the first-generation ozonide OZ277, OZ439 exhibits a substantial increase in the pharmacokinetic half-life and blood concentration versus time profile in three preclinical species. The outstanding efficacy and prolonged blood concentrations of OZ439 are the result of a design strategy that stabilizes the intrinsically unstable pharmacophoric peroxide bond, thereby reducing clearance yet maintaining the necessary Fe(II)-reactivity to elicit parasite death. PMID:21300861

  3. Biotransformation of ethanol to ethyl glucuronide in a rat model after a single high oral dosage.

    PubMed

    Wright, Trista H; Ferslew, Kenneth E

    2012-03-01

    Ethyl glucuronide (EtG) is a minor ethanol metabolite that confirms the absorption and metabolism of ethanol after oral or dermal exposure. Human data suggest that maximum blood EtG (BEtG) concentrations are reached between 3.5 and 5.5h after ethanol administration. This study was undertaken to determine if the Sprague-Dawley (SD) rat biotransforms ethanol to EtG after a single high oral dose of ethanol. SD rats (male, n=6) were gavaged with a single ethanol dose (4 g/kg), and urine was collected for 3 h in metabolic cages, followed by euthanization and collection of heart blood. Blood and urine were analyzed for ethanol and EtG by gas chromatography and enzyme immunoassay. Blood and urine ethanol concentrations were 195±23 and 218±19 mg/dL, whereas BEtG and urine EtG (UEtG) concentrations were 1,363±98 ng equivalents/mL and 210±0.29 mg equivalents/dL (X ± standard error of the mean [S.E.M.]). Sixty-six male SD rats were gavaged ethanol (4 g/kg) and placed in metabolic cages to determine the extent and duration of ethanol to EtG biotransformation and urinary excretion. Blood and urine were collected up to 24 h after administration for ethanol and EtG analysis. Maximum blood ethanol, urine ethanol, and UEtG were reached within 4 h, whereas maximum BEtG was reached 6 h after administration. Maximum concentrations were blood ethanol, 213±20 mg/dL; urine ethanol, 308±34 mg/dL; BEtG, 2,683±145 ng equivalents/mL; UEtG, 1.2±0.06 mg equivalents/mL (X±S.E.M.). Areas under the concentration-time curve were blood ethanol, 1,578 h*mg/dL; urine ethanol, 3,096 h*mg/dL; BEtG, 18,284 h*ng equivalents/mL; and UEtG, 850 h*mg equivalents/dL. Blood ethanol and BEtG levels were reduced to below limits of detection (LODs) within 12 and 18 h after ethanol administration. Urine ethanols were below LOD at 18 h, but UEtG was still detectable at 24h after administration. Our data prove that the SD rat biotransforms ethanol to EtG and excretes both in the urine and suggest that it

  4. Biotransformation of ethanol to ethyl glucuronide in a rat model after a single high oral dosage.

    PubMed

    Wright, Trista H; Ferslew, Kenneth E

    2012-03-01

    Ethyl glucuronide (EtG) is a minor ethanol metabolite that confirms the absorption and metabolism of ethanol after oral or dermal exposure. Human data suggest that maximum blood EtG (BEtG) concentrations are reached between 3.5 and 5.5h after ethanol administration. This study was undertaken to determine if the Sprague-Dawley (SD) rat biotransforms ethanol to EtG after a single high oral dose of ethanol. SD rats (male, n=6) were gavaged with a single ethanol dose (4 g/kg), and urine was collected for 3 h in metabolic cages, followed by euthanization and collection of heart blood. Blood and urine were analyzed for ethanol and EtG by gas chromatography and enzyme immunoassay. Blood and urine ethanol concentrations were 195±23 and 218±19 mg/dL, whereas BEtG and urine EtG (UEtG) concentrations were 1,363±98 ng equivalents/mL and 210±0.29 mg equivalents/dL (X ± standard error of the mean [S.E.M.]). Sixty-six male SD rats were gavaged ethanol (4 g/kg) and placed in metabolic cages to determine the extent and duration of ethanol to EtG biotransformation and urinary excretion. Blood and urine were collected up to 24 h after administration for ethanol and EtG analysis. Maximum blood ethanol, urine ethanol, and UEtG were reached within 4 h, whereas maximum BEtG was reached 6 h after administration. Maximum concentrations were blood ethanol, 213±20 mg/dL; urine ethanol, 308±34 mg/dL; BEtG, 2,683±145 ng equivalents/mL; UEtG, 1.2±0.06 mg equivalents/mL (X±S.E.M.). Areas under the concentration-time curve were blood ethanol, 1,578 h*mg/dL; urine ethanol, 3,096 h*mg/dL; BEtG, 18,284 h*ng equivalents/mL; and UEtG, 850 h*mg equivalents/dL. Blood ethanol and BEtG levels were reduced to below limits of detection (LODs) within 12 and 18 h after ethanol administration. Urine ethanols were below LOD at 18 h, but UEtG was still detectable at 24h after administration. Our data prove that the SD rat biotransforms ethanol to EtG and excretes both in the urine and suggest that it

  5. Low-dose oral cadmium increases airway reactivity and lung neuronal gene expression in mice.

    PubMed

    Chandler, Joshua D; Wongtrakool, Cherry; Banton, Sophia A; Li, Shuzhao; Orr, Michael L; Barr, Dana Boyd; Neujahr, David C; Sutliff, Roy L; Go, Young-Mi; Jones, Dean P

    2016-07-01

    Inhalation of cadmium (Cd) is associated with lung diseases, but less is known concerning pulmonary effects of Cd found in the diet. Cd has a decades-long half-life in humans and significant bioaccumulation occurs with chronic dietary intake. We exposed mice to low-dose CdCl2 (10 mg/L in drinking water) for 20 weeks, which increased lung Cd to a level similar to that of nonoccupationally exposed adult humans. Cd-treated mice had increased airway hyperresponsiveness to methacholine challenge, and gene expression array showed that Cd altered the abundance of 443 mRNA transcripts in mouse lung. In contrast to higher doses, low-dose Cd did not elicit increased metallothionein transcripts in lung. To identify pathways most affected by Cd, gene set enrichment of transcripts was analyzed. Results showed that major inducible targets of low-dose Cd were neuronal receptors represented by enriched olfactory, glutamatergic, cholinergic, and serotonergic gene sets. Olfactory receptors regulate chemosensory function and airway hypersensitivity, and these gene sets were the most enriched. Targeted metabolomics analysis showed that Cd treatment also increased metabolites in pathways of glutamatergic (glutamate), serotonergic (tryptophan), cholinergic (choline), and catecholaminergic (tyrosine) receptors in the lung tissue. Protein abundance measurements showed that the glutamate receptor GRIN2A was increased in mouse lung tissue. Together, these results show that in mice, oral low-dose Cd increased lung Cd to levels comparable to humans, increased airway hyperresponsiveness and disrupted neuronal pathways regulating bronchial tone. Therefore, dietary Cd may promote or worsen airway hyperresponsiveness in multiple lung diseases including asthma.

  6. Low-dose oral cadmium increases airway reactivity and lung neuronal gene expression in mice.

    PubMed

    Chandler, Joshua D; Wongtrakool, Cherry; Banton, Sophia A; Li, Shuzhao; Orr, Michael L; Barr, Dana Boyd; Neujahr, David C; Sutliff, Roy L; Go, Young-Mi; Jones, Dean P

    2016-07-01

    Inhalation of cadmium (Cd) is associated with lung diseases, but less is known concerning pulmonary effects of Cd found in the diet. Cd has a decades-long half-life in humans and significant bioaccumulation occurs with chronic dietary intake. We exposed mice to low-dose CdCl2 (10 mg/L in drinking water) for 20 weeks, which increased lung Cd to a level similar to that of nonoccupationally exposed adult humans. Cd-treated mice had increased airway hyperresponsiveness to methacholine challenge, and gene expression array showed that Cd altered the abundance of 443 mRNA transcripts in mouse lung. In contrast to higher doses, low-dose Cd did not elicit increased metallothionein transcripts in lung. To identify pathways most affected by Cd, gene set enrichment of transcripts was analyzed. Results showed that major inducible targets of low-dose Cd were neuronal receptors represented by enriched olfactory, glutamatergic, cholinergic, and serotonergic gene sets. Olfactory receptors regulate chemosensory function and airway hypersensitivity, and these gene sets were the most enriched. Targeted metabolomics analysis showed that Cd treatment also increased metabolites in pathways of glutamatergic (glutamate), serotonergic (tryptophan), cholinergic (choline), and catecholaminergic (tyrosine) receptors in the lung tissue. Protein abundance measurements showed that the glutamate receptor GRIN2A was increased in mouse lung tissue. Together, these results show that in mice, oral low-dose Cd increased lung Cd to levels comparable to humans, increased airway hyperresponsiveness and disrupted neuronal pathways regulating bronchial tone. Therefore, dietary Cd may promote or worsen airway hyperresponsiveness in multiple lung diseases including asthma. PMID:27401458

  7. Utilizing a novel tandem oral dosing strategy to enhance exposure of low-solubility drug candidates in a preclinical setting.

    PubMed

    Chiang, Po-Chang; South, Sarah A; Foster, Kimberly A; Daniels, J Scott; Wene, Steve P; Albin, Lesley A; Thompson, David C

    2010-07-01

    Time and resource constraints necessitate increasingly early decision making to accelerate or stop preclinical drug discovery programs. Early discovery drug candidates may be potent inhibitors of new targets, but all too often exhibit poor pharmaceutical and pharmacokinetic properties that limit the in vivo exposure. Low solubility of a drug candidate often leads to poor oral bioavailability and poor dose linearity that creates an issue for efficacy and target safety studies, where high drug exposures are desired. When solubility issues are encountered, enabling formulations are often used to improve the exposure. However, this approach often requires a substantial and lengthy investment to develop the formulation. In our study, two drug candidates with poor aqueous solubility were dosed in rats as simple suspension formulations using a novel tandem dosing strategy, which employs dosing orally in 2.5 h increments up to three times to simulate an oral infusion by avoiding saturation of absorption associated with bolus dosing. These compounds were also dosed using the same suspension formulations and a standard dosing strategy. The resulting in vivo exposures were compared. It was found that this novel tandem dosing strategy significantly improved the in vivo exposures.

  8. Fixed-dose combinations of drugs versus single-drug formulations for treating pulmonary tuberculosis

    PubMed Central

    Gallardo, Carmen R; Rigau Comas, David; Valderrama Rodríguez, Angélica; Roqué i Figuls, Marta; Parker, Lucy Anne; Caylà, Joan; Bonfill Cosp, Xavier

    2016-01-01

    LANGUAGE SUMMARY Fixed-dose combinations for treating pulmonary tuberculosis What are fixed-dose combinations and how might they improve care of people with tuberculosis Tuberculosis (TB) is an important health problem, especially in developing countries. The treatment for pulmonary TB in new patients includes four oral medicines taken for six months, sometimes as fixed-dose combinations (FDCs) that are combined in one tablet, or taken separately as single-drug formulations. The World Health Organization recommends prescribers use fixed-dose combinations to reduce the number of tablets that people take. On the supply side, this might reduce prescribing errors and improve drug supply efficiency; on the patient's side, FDCS simplify treatment and improve adherence. We conducted a review to assess the efficacy, safety, and acceptability of FDCs compared with single-drug formulations for treating people with newly diagnosed pulmonary TB. What the research says We searched for relevant trials up to 20 November 2015, and included 13 randomized controlled trials that enrolled 5824 people. Trials were published between 1987 and 2015 and included participants in treatment with newly diagnosed pulmonary TB in countries with high TB prevalence. Only two trials reported the HIV status of included participants. There is probably little or no difference in FDCs compared to single-drug formulations for treatment failure (moderate quality evidence); relapse may be more frequent (low quality evidence); and the number of deaths were similar (moderate quality evidence). There is little or no difference in sputum smear or culture conversion (high quality evidence), and no difference was shown for serious adverse events (moderate quality evidence) or adverse events that led to discontinuation of therapy (low quality evidence). Authors' conclusions We concluded that fixed-dose combinations have similar efficacy to single-drug formulations for treating people with newly diagnosed pulmonary TB

  9. Relapsing insulin-induced lipoatrophy, cured by prolonged low-dose oral prednisone: a case report

    PubMed Central

    2011-01-01

    Introduction Circumscript, progressing lipoatrophy at the insulin injection sites is an unexplained, however rare condition in diabetes mellitus. Case presentation We report a case of severe localised lipoatrophy developing during insulin pump-treatment (continuous subcutaneous insulin infusion) with the insulin analogue lispro (Humalog®) in a woman with type-1 diabetes mellitus. After 11 months of progressing lipoatrophy at two spots on the abdomen, low-dose prednisone (5-10 mg) p.o. was given at breakfast for 8 months, whereby the atrophic lesions centripetally re-filled with subcutaneous fat tissue (confirmed by MRI) despite ongoing use of insulin lispro. However, 4 weeks after cessation of prednisone, lipoatrophy relapsed, but resolved after another 2 months of low-dose prednisone. No further relapse was noted during 12 months of follow-up on insulin-pump therapy with Humalog®. Conclusion Consistent with an assumed inflammatory nature of the condition, low-dose oral prednisone appeared to have cured the lipoatrophic reaction in our patient. Our observation suggests a temporary intolerance of the subcutaneous fat tissue to insulin lispro (Humalog®), triggered by an unknown endogenous mechanism. PMID:22145998

  10. [Exercise-induced asthma in children and oral terbutaline. A dose-response relationship study].

    PubMed

    Hertz, B; Fuglsang, G; Holm, E B

    1994-09-26

    We wanted to assess the protective effects on exercise-induced asthma as well as the clinical efficacy and safety of increasing doses of a new sustained-release formulation of terbutaline sulphate in 17 asthmatic children aged 6-12 years (mean 9 years). Placebo, 2, 4, and 6 mg terbutaline were given b.i.d. for 14 days in a randomized, double-blind, cross-over design. At the end of each two week period, an exercise test was performed and plasma terbutaline was measured. Compared with placebo, no significant effect was seen on asthma symptoms monitored at home, or on exercise-induced asthma. The percentage falls in FEV1 after the exercise test were 36, 35, 27 and 28%, after placebo, 4, 8 and 12 mg terbutaline/day, respectively. A small but statistically significant dose-related increase was seen in morning and evening peak expiratory flow (PEF) recordings. It is concluded that continuous treatment, even with high doses or oral terbutaline, does not offer clinically useful protection against exercise-induced asthma. PMID:7985255

  11. A single-dose regimen for antimicrobial prophylaxis to prevent perioperative infection in urological clean and clean-contaminated surgery.

    PubMed

    Higuchi, Yoshihide; Takesue, Yoshio; Yamada, Yusuke; Ueda, Yasuo; Suzuki, Toru; Aihara, Kinue; Maruyama, Takuo; Kondoh, Nobuyuki; Nojima, Michio; Yamamoto, Shingo

    2011-04-01

    A single dose of antimicrobial prophylaxis (AMP) was administered parenterally for the prevention of perioperative infection in a total of 788 patients undergoing urological surgery, including 380 endoscopic-instrumental, 328 clean, and 80 clean-contaminated operations performed at our institute between January 2007 and December 2009. Surgical site infections (SSIs), urinary tract infections (UTIs), and remote infections (RIs) were prospectively surveyed. The definition for a single dose of AMP allowed for the administration of an additional dose of an antimicrobial during surgery if the procedure was longer than 3 h, but not for the parenteral or oral administration at the end of the procedure in the recovery room, or at a later time over a period of more than 24 h. UTI was observed in 12 (3.2%) patients after endoscopic-instrumental operation, 1 (0.3%) after clean operation, and 1 (0.9%) after clean-contaminated operation. SSI was observed in 2 (0.6%) patients after clean operation but in none after clean-contaminated operations. RI was observed in 1 (0.3%) patient after endoscopic-instrumental operation, 3 (0.9%) after clean operation, and none after clean-contaminated operations. A single-dose regimen of AMP was effective and feasible for the prevention of perioperative infections, including SSIs, UTIs, and RIs, in endoscopic-instrumental, clean, and clean-contaminated urological surgical procedures.

  12. Single-Dose Pharmacokinetic Study of Tramadol Extended-Release Tablets in Children and Adolescents.

    PubMed

    Vandenbossche, Joris; Van Peer, Achiel; Richards, Henry

    2016-09-01

    Combined analyses from 2 open-label, phase-1 studies-the pharmacokinetic profile of tramadol and its metabolite (M1) following a single oral dose of tramadol extended release (ER) (25 to 100 mg) in children (7 to 11 years old; study 1: n = 37) and adolescents (12 to 17 years old; study 2: n = 38) with painful conditions-were historically compared with that of healthy adults following similar dosing. The dose-normalized area under the curve (DN AUC0-24h ) and maximum concentration (DN Cmax ) of tramadol and of M1 in children and in adolescents were lower than those in adults (children vs adults: tramadol, DN AUC0-24h 82.19%; DN Cmax 80.38%, P = .0031; M1, DN AUC0-24h 51.19%, DN Cmax 52.68%, P < .0001; adolescents vs adults: tramadol, DN AUC0-24h 89.56%, DN Cmax 84.01%; M1, DN AUC0-24h 85.28%, DN Cmax 83.03%, P = .0004). The arithmetic mean terminal elimination t1/2 of tramadol in children and adolescents was comparable to that in adults (children 8.4 hours; adolescents 8.5 hours; adults 7.9 hours). The most frequently reported (≥5% of participants) treatment-emergent adverse events in children included headache, upper abdominal pain and constipation, and in adolescents were headache, nausea, dizziness, and stomach discomfort. Multiple factors may have contributed to these observations, including a higher proportion of children (56%) who may have a lower activity of CYP2D6, resulting in reduced clearance of tramadol.

  13. Absorption, distribution, and elimination of graded oral doses of methylmercury in juvenile white sturgeon.

    PubMed

    Huang, Susie Shih-Yin; Strathe, Anders Bjerring; Fadel, James G; Lin, Pinpin; Liu, Tsung-Yun; Hung, Silas S O

    2012-10-15

    Mercury (Hg) is toxic and is released into the environment from a wide variety of anthropogenic sources. Methylmercury (MeHg), a product of microbial methylation, enables rapid Hg bioaccumulation and biomagnification in the biota. Methylmercury is sequestered and made available to the rest of the biota through the benthic-detrital component leading to the high risk of exposure to benthic fish species, such as white sturgeon (Acipenser transmontanus). In the present study, a combined technique of stomach intubation, dorsal aorta cannulation, and urinary catheterization was utilized to characterize the absorption, distribution, and elimination of Hg in white sturgeon over a 48h exposure. Mercury, as methylmercury chloride, at either 0, 250, 500, or 1000 μg Hg/kg body weight, was orally intubated into white sturgeon, in groups of five. The blood was repeatedly sampled and urine collected from the fish over the 48h post intubation period, and at 48h, the fish were sacrificed for Hg tissue concentration and distribution determinations. The fractional rate of absorption (K), blood Hg concentration (μg/ml), tissue concentration (μg/g dry weight) and distribution (%), and urinary Hg elimination flux (μg/kg/h) are significantly different (p<0.05) among the MeHg doses. Complete blood uptake of Hg was observed in all MeHg treated fish by 12h. The maximal observed blood Hg concentration peaks are 0.56±0.02, 0.70±0.02, and 2.19±0.07 μg/ml (mean±SEM) for the 250, 500, and 1000 μgHg/kg body weight dose groups, respectively. Changes in blood Hg profiles can be described by a monomolecular function in all of the MeHg treated fish. The Hg concentration asymptote (A) and K are dose dependent. The relationship between A and the intubation dose, however, is nonlinear. Mercury levels in certain tissues are comparable to field data and longer-term study, indicating that the lower doses used in the current study are ecologically relevant for the species. Tissue Hg concentrations

  14. Determination of the effective dose of a novel oral formulation of sarolaner (Simparica™) for the treatment and month-long control of fleas and ticks on dogs.

    PubMed

    McTier, Tom L; Six, Robert H; Fourie, Josephus J; Pullins, Aleah; Hedges, Laura; Mahabir, Sean P; Myers, Melanie R

    2016-05-30

    for 5 weeks. There was no significant improvement in efficacy provided by the 4.0 mg/kg dose over the 2.0mg/kg dose (P>0.05) at any time point. The 2.0mg/kg dose was superior to the 1.0mg/kg on Day 14 (P=0.0086) and as efficacy for 1.0mg/kg declined below 90% at Day 28, a single 1mg/kg dose would not provide a full month of tick control. Thus, 2.0mg/kg was selected as the sarolaner dose rate to provide flea and tick control for at least one month following a single oral treatment.

  15. Determination of the effective dose of a novel oral formulation of sarolaner (Simparica™) for the treatment and month-long control of fleas and ticks on dogs.

    PubMed

    McTier, Tom L; Six, Robert H; Fourie, Josephus J; Pullins, Aleah; Hedges, Laura; Mahabir, Sean P; Myers, Melanie R

    2016-05-30

    for 5 weeks. There was no significant improvement in efficacy provided by the 4.0 mg/kg dose over the 2.0mg/kg dose (P>0.05) at any time point. The 2.0mg/kg dose was superior to the 1.0mg/kg on Day 14 (P=0.0086) and as efficacy for 1.0mg/kg declined below 90% at Day 28, a single 1mg/kg dose would not provide a full month of tick control. Thus, 2.0mg/kg was selected as the sarolaner dose rate to provide flea and tick control for at least one month following a single oral treatment. PMID:26948830

  16. Pharmacokinetics of enoxacin and its oxometabolite after multiple oral dosing and penetration into prostatic tissue.

    PubMed

    Hamel, B; Mottet, N; Audran, M; Costa, P; Bressolle, F

    2000-12-01

    The objective of this study was to determine the concentrations of enoxacin and its oxo-metabolite in human prostatic tissue after multiple oral doses (400 mg bd) in 13 patients. On the first day of treatment, elimination half-lives were 6.8 h for enoxacin and 7.1 h for its metabolite; they were increased on day 4 (10.3 and 13.2 h, respectively). The ratios of drug concentration in prostatic tissue and plasma averaged 2.2 for enoxacin and 1.4 for its metabolite. In conclusion, concentrations of enoxacin achieved within the prostatic tissue were higher than plasma concentrations suggesting that there was an active transport mechanism.

  17. Prospective Evaluation to Establish a Dose Response for Clinical Oral Mucositis in Patients Undergoing Head-and-Neck Conformal Radiotherapy

    SciTech Connect

    Narayan, Samir Lehmann, Joerg; Coleman, Matthew A.; Vaughan, Andrew; Yang, Claus Chunli; Enepekides, Danny; Farwell, Gregory; Purdy, James A.; Laredo, Grace; Nolan, Kerry A.S.; Pearson, Francesca S.; Vijayakumar, Srinivasan

    2008-11-01

    Purpose: We conducted a clinical study to correlate oral cavity dose with clinical mucositis, perform in vivo dosimetry, and determine the feasibility of obtaining buccal mucosal cell samples in patients undergoing head-and-neck radiation therapy. The main objective is to establish a quantitative dose response for clinical oral mucositis. Methods and Materials: Twelve patients undergoing radiation therapy for head-and-neck cancer were prospectively studied. Four points were chosen in separate quadrants of the oral cavity. Calculated dose distributions were generated by using AcQPlan and Eclipse treatment planning systems. MOSFET dosimeters were used to measure dose at each sampled point. Each patient underwent buccal sampling for future RNA analysis before and after the first radiation treatment at the four selected points. Clinical and functional mucositis were assessed weekly according to National Cancer Institute Common Toxicity Criteria, Version 3. Results: Maximum and average doses for sampled sites ranged from 7.4-62.3 and 3.0-54.3 Gy, respectively. A cumulative point dose of 39.1 Gy resulted in mucositis for 3 weeks or longer. Mild severity (Grade {<=} 1) and short duration ({<=}1 week) of mucositis were found at cumulative point doses less than 32 Gy. Polymerase chain reaction consistently was able to detect basal levels of two known radiation responsive genes. Conclusions: In our sample, cumulative doses to the oral cavity of less than 32 Gy were associated with minimal acute mucositis. A dose greater than 39 Gy was associated with longer duration of mucositis. Our technique for sampling buccal mucosa yielded sufficient cells for RNA analysis using polymerase chain reaction.

  18. A chronic oral reference dose for hexavalent chromium-induced intestinal cancer.

    PubMed

    Thompson, Chad M; Kirman, Christopher R; Proctor, Deborah M; Haws, Laurie C; Suh, Mina; Hays, Sean M; Hixon, J Gregory; Harris, Mark A

    2014-05-01

    High concentrations of hexavalent chromium [Cr(VI)] in drinking water induce villous cytotoxicity and compensatory crypt hyperplasia in the small intestines of mice (but not rats). Lifetime exposure to such cytotoxic concentrations increases intestinal neoplasms in mice, suggesting that the mode of action for Cr(VI)-induced intestinal tumors involves chronic wounding and compensatory cell proliferation of the intestine. Therefore, we developed a chronic oral reference dose (RfD) designed to be protective of intestinal damage and thus intestinal cancer. A physiologically based pharmacokinetic model for chromium in mice was used to estimate the amount of Cr(VI) entering each intestinal tissue section (duodenum, jejunum and ileum) from the lumen per day (normalized to intestinal tissue weight). These internal dose metrics, together with corresponding incidences for diffuse hyperplasia, were used to derive points of departure using benchmark dose modeling and constrained nonlinear regression. Both modeling techniques resulted in similar points of departure, which were subsequently converted to human equivalent doses using a human physiologically based pharmacokinetic model. Applying appropriate uncertainty factors, an RfD of 0.006 mg kg(-1) day(-1) was derived for diffuse hyperplasia-an effect that precedes tumor formation. This RfD is protective of both noncancer and cancer effects in the small intestine and corresponds to a safe drinking water equivalent level of 210 µg l(-1). This concentration is higher than the current federal maximum contaminant level for total Cr (100 µg l(-1)) and well above levels of Cr(VI) in US drinking water supplies (typically ≤ 5 µg l(-1)). PMID:23943231

  19. Use of a monophasic, low-dose oral contraceptive in relation to mental functioning.

    PubMed

    Deijen, J B; Duyn, K J; Jansen, W A; Klitsie, J W

    1992-10-01

    The objective of the study was to evaluate the effect of Minulet, a new low-dose oral contraceptive on mood in two groups and to compare the effect with a control group of women not taking oral contraceptives (OC). The women participating were between 16 and 45 years of age. They completed the Amsterdam Mood Questionnaire (AMQ) and the Sickness Impact Profile (SIP) three times. They were filled in before treatment started, after taking Minulet for one month and then again after three months. The questionnaires were filled in by a group of 200 women who had not taken OC before (starters), and by a second group of 370 women who were already taking OC (switchers). A group of 140 women who did not use any OC during the study served as a control group. These women also filled in the same questionnaires, both at the start, and after one and three months. As far as the AMQ was concerned, the switchers appeared in the initial measurement to have significantly higher scores (that is to say, a worse mood) for "tiredness", "depression", "moodiness", "anxiety" and "anger", than those of the starters and the control group. Moreover, the switchers had reduced scores (that is to say, an improved mood) on the AMQ-scales during their use of Minulet compared to their initial use of oral contraceptives. The scores of the starters and the control group on the AMQ-scales remained unchanged on all three measurements. It can be concluded from this that these groups felt as well as they did before.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. Quality of Life of Oral Cancer Patients After Low-Dose-Rate Interstitial Brachytherapy

    SciTech Connect

    Yoshimura, Ryo-ichi Shibuya, Hitoshi; Miura, Masahiko; Watanabe, Hiroshi; Ayukawa, Fumio; Hayashi, Keiji; Toda, Kazuma

    2009-03-01

    Purpose: To assess the quality of life (QOL) of oral cancer patients treated with low-dose-rate interstitial brachytherapy (LDR-BT) alone. Methods and Materials: Between June 2005 and July 2006, a total of 56 patients with oral cancer were enrolled in this prospective study. QOL was assessed by means of the core questionnaire and head and neck questionnaire module of the European Organization for Research and Treatment of Cancer (EORTC Quality of Life Questionnaire-Core 30 [QLQ-C30] and QLQ Head and Neck 35 [H and N35]). The questionnaires were distributed to the patients before the start of treatment and 3 months, 6 months, and 12 months after the start of LDR-BT. Results: It was possible to analyze the results for 20 of the initial 56 patients because they did not experience metastasis or recurrence during this study. No functions or symptoms asked about in the QLQ-C30 deteriorated during the first year. The emotional function score steadily and significantly increased. No symptoms in the QLQ-H and N35 significantly deteriorated. The scores for pain, trouble with social eating, and weight loss on the QLQ-H and N35 steadily and significantly decreased. Age, gender, and LDR-BT source had no effect on the change in QOL during the first year, but T-stage significantly affected the change in global health status, tumor site affected the changes in swallowing, sensory problems, sticky saliva, and complications affected the changes in pain, swallowing, and mouth opening. Conclusions: QOL of oral cancer patients treated with LDR-BT is high. However, tumor stage, tumor site, and complications affected the changes in a few functions and symptoms during the first year.

  1. Evaluation of the bioequivalence and pharmacokinetics of two formulations of rizatriptan after single oral administration in healthy volunteers.

    PubMed

    Chen, Jun; Jiang, Wen Ming; Xie, Yue Ling; Jin, Liang; Mei, Ni; Liang, Xin Guo

    2005-01-01

    The pharmacokinetic parameters of two oral formulations of rizatriptan (CAS 144034-80-0, a capsule preparation as test and rizatriptan tablet as reference), given at a single dose of 10 mg each, were compared in an open-label, randomized, single oral dose, two-period cross-over design in 20 healthy volunteers under fasting conditions. Plasma concentrations of rizatriptan were measured by a validated HPLC assay. The parametric 90% confidence intervals of the geometric mean values of the test/reference ratios were 91.9% to 101.9% (point estimate: 97.3%) for AUC(0-infinity), 93.0% to 102.2% (point estimate: 96.5%) for AUC(0-t), 90.1% to 100.0% (point estimate: 95.4%) for Cmax, being within the acceptance criteria for bioequivalence (80%-125%). Tmax values were analyzed by the nonparametric Wilcoxon test and the difference was not statistically significant. Therefore, it is concluded that the test and reference rizatriptan formulations are bioequivalent with regard to both the extent and the rate of absorption. PMID:16080273

  2. Low-dose irradiation affects the functional behavior of oral microbiota in the context of mucositis

    PubMed Central

    De Ryck, Tine RG; De boel, Kevin; Wiles, Siouxsie; Boterberg, Tom; Van de Wiele, Tom; Swift, Simon

    2015-01-01

    The role of host–microbe interactions in the pathobiology of oral mucositis is still unclear; therefore, this study aimed to unravel the effect of irradiation on behavioral characteristics of oral microbial species in the context of mucositis. Using various experimental in vitro setups, the effects of irradiation on growth and biofilm formation of two Candida spp., Streptococcus salivarius and Klebsiella oxytoca in different culture conditions were evaluated. Irradiation did not affect growth of planktonic cells, but reduced the number of K. oxytoca cells in newly formed biofilms cultured in static conditions. Biofilm formation of K. oxytoca and Candida glabrata was affected by irradiation and depended on the culturing conditions. In the presence of mucins, these effects were lost, indicating the protective nature of mucins. Furthermore, the Galleria melonella model was used to study effects on microbial virulence. Irradiated K. oxytoca microbes were more virulent in G. melonella larvae compared to the nonirradiated ones. Our data indicate that low-dose irradiation can have an impact on functional characteristics of microbial species. Screening for pathogens like K. oxytoca in the context of mucosits could be useful to allow early detection and immediate intervention. PMID:26202372

  3. Oral exposure to low-dose of nonylphenol impairs memory performance in Sprague-Dawley rats.

    PubMed

    Kawaguchi, Shinichiro; Kuwahara, Rika; Kohara, Yumi; Uchida, Yutaro; Oku, Yushi; Yamashita, Kimihiro

    2015-02-01

    Nonylphenol ethoxylate (NPE) is a non-ionic surfactant, that is degraded to short-chain NPE and 4-nonylphenol (NP) by bacteria in the environment. NP, one of the most common environmental endocrine disruptors, exhibits weak estrogen-like activity. In this study, we investigated whether oral administration of NP (at 0.5 and 5 mg/kg doses) affects spatial learning and memory, general activity, emotionality, and fear-motivated learning and memory in male and female Sprague-Dawley (SD) rats. SD rats of both sexes were evaluated using a battery of behavioral tests, including an appetite-motivated maze test (MAZE test) that was used to assess spatial learning and memory. In the MAZE test, the time required to reach the reward in male rats treated with 0.5 mg/kg NP group and female rats administered 5 mg/kg NP was significantly longer than that for control animals of the corresponding sex. In other behavioral tests, no significant differences were observed between the control group and either of the NP-treated groups of male rats. In female rats, inner and ambulation values for animals administered 0.5 mg/kg NP were significantly higher than those measured in control animals in open-field test, while the latency in the group treated with 5 mg/kg NP was significantly shorter compared to the control group in step-through passive avoidance test. This study indicates that oral administration of a low-dose of NP slightly impairs spatial learning and memory performance in male and female rats, and alters emotionality and fear-motivated learning and memory in female rats only. PMID:25560395

  4. The pharmacokinetics and dosing of oral 4-methylumbelliferone for inhibition of hyaluronan synthesis in mice.

    PubMed

    Kuipers, H F; Nagy, N; Ruppert, S M; Sunkari, V G; Marshall, P L; Gebe, J A; Ishak, H D; Keswani, S G; Bollyky, J; Frymoyer, A R; Wight, T N; Steinman, L; Bollyky, P L

    2016-09-01

    Recently, there has been considerable interest in using 4-methylumbelliferone (4-MU) to inhibit hyaluronan (HA) synthesis in mouse models of cancer, autoimmunity and a variety of other inflammatory disorders where HA has been implicated in disease pathogenesis. In order to facilitate future studies in this area, we have examined the dosing, treatment route, treatment duration and metabolism of 4-MU in both C57BL/6 and BALB/c mice. Mice fed chow containing 5% 4-MU, a dose calculated to deliver 250 mg/mouse/day, initially lose substantial weight but typically resume normal weight gain after 1 week. It also takes up to a week to see a reduction in serum HA in these animals, indicating that at least a 1-week loading period on the drug is required for most protocols. At steady state, more than 90% of the drug is present in plasma as the glucuronidated metabolite 4-methylumbelliferyl glucuronide (4-MUG), with the sulphated metabolite, 4-methylumbelliferyl sulphate (4-MUS) comprising most of the remainder. Chow containing 5% but not 0·65% 4-MU was effective at preventing disease in the experimental autoimmune encephalomyelitis (EAE) mouse model of multiple sclerosis, as well as in the DORmO mouse model of autoimmune diabetes. While oral 4-MU was effective at preventing EAE, daily intraperitoneal injections of 4-MU were not. Factors potentially affecting 4-MU uptake and plasma concentrations in mice include its taste, short half-life and low bioavailability. These studies provide a practical resource for implementing oral 4-MU treatment protocols in mice. PMID:27218304

  5. Pharmacodynamics and pharmacokinetics of oral levosimendan and its metabolites in patients with severe congestive heart failure: a dosing interval study.

    PubMed

    Põder, Pentti; Eha, Jaan; Sundberg, Stig; Antila, Saila; Heinpalu, Marika; Loogna, Imbrit; Planken, Ulle; Rantanen, Satu; Lehtonen, Lasse

    2004-10-01

    The objective of this study was to explore the pharmacodynamics and pharmacokinetics of oral levosimendan in patients with severe congestive heart failure. This was a randomized, parallel-group, double-blind, placebo-controlled trial. Oral levosimendan 2 to 8 mg daily or placebo was administered to 25 patients with New York Heart Association class III-IV congestive heart failure for 4 weeks. Pharmacodynamic variables consisted of heart rate-corrected electromechanical systole, heart rate, and systolic and diastolic blood pressure. The pharmacokinetics of levosimendan and its metabolites, OR-1855 and OR-1896, was assessed. The 4- to 8-mg daily doses of oral levosimendan showed moderate inotropic effects. Blood pressure remained unchanged with all doses. A moderate increase in heart rate was observed except with the 2-mg dose. Pharmacokinetic parameters of the metabolites increased linearly with the dose (P < or = .002 for Cmax and AUC0-8h for both treatment groups). It was concluded that oral levosimendan has inotropic and chronotropic effects in patients with severe congestive heart failure. Plasma concentrations of its metabolites increase dose dependently.

  6. Vitamin E levels in sheep tissues at various times after a single oral administration of d-alpha-tocopherol acetate.

    PubMed

    Hidiroglou, M

    1987-01-01

    Five groups, each of 5 sheep of 40-45 kg body weight were used. One group acted as control (killed at 0 time, no vitamin E dose) while the other four groups were given a single oral dose of d-alpha-tocopherol acetate (100 mg/kg body weight) and killed 24, 48, 72 and 240 h after dosing. Samples of adrenal, adipose, heart, liver, kidney, lung, muscle, pancreas and spleen were taken from all 25 sheep and were analyzed for their vitamin E content. In the control sheep the tocopherol concentration in some tissues such as pancreas and adrenal were substantially higher than in the other tissues. Muscle and adipose tissue contained the lowest tocopherol concentrations among the various tissues. Tissues responded differently to the vitamin E dosing. Liver was characterized by a rapid accumulation of alpha-tocopherol at 24 h followed by a progressive loss. In the adrenal and lung the peak occurred 48 h after vitamin E loading. The variable pattern in tocopherol concentrations in the various sheep tissues following vitamin E dosing was considered a reflection of their different metabolic activities.

  7. Single daily dosing of gentamicin: pharmacokinetic comparison of two dosing methodologies for postpartum endometritis.

    PubMed Central

    Liu, C; Abate, B; Reyes, M; Gonik, B

    1999-01-01

    OBJECTIVE: We compared the pharmacokinetics of two methods for dosing gentamicin for the treatment of postpartum endometritis with the goal of achieving adequate peak serum concentrations (>12 mg/L) and prolonged trough levels below 2 mg/L. METHODS: Group-I subjects (n = 5) received intravenous gentamicin, 5 mg/kg per total body weight over 60 min., with a maximum dose of 500 mg. Group-II subjects (n = 17) were dosed intravenously according to the following formula: Dose = desired peak concentration (fixed at 14 mg/L) * (volume of distribution, i.e., 0.35 L/kg) * adjusted body weight (in kilograms). Serum gentamicin levels were obtained 1 hr. and 8-12 hr. after infusion of the second dose. Pharmacokinetic parameters for the subjects in each group were calculated according to standard formulas. RESULTS: Subjects in Group I had significantly higher doses and peak drug concentrations (P < 0.01), while in Group II, 76% of patients had peak levels less than desired (<12 mg/L). Both groups maintained trough levels of <2 mg/L in excess of 12 hr. CONCLUSIONS: Changing to the adjusted body weight formula for Group I, while maintaining a dose between 4 and 5 mg/kg, would reduce excessive peak concentrations. Using a calculated volume of distribution of 0.4 L/kg in Group II would improve peak serum concentrations to the desired levels. Both dosing regimens ensure adequate aminoglycoside pharmacokinetic parameters and avoid the need for monitoring serial serum drug concentrations, provided the expected clinical response is also achieved. While the first dosing formula is simpler to calculate, the second dosing formula allows for more individualized dosing considerations. PMID:10371471

  8. Dose and schedule-finding study of oral topotecan and weekly cisplatin in patients with recurrent ovarian cancer

    PubMed Central

    Gelderblom, H; Sparreboom, A; Jonge, M J A de; Loos, W J; Wilms, E; Mantel, M A; Hennis, B; Camlett, I; Verweij, J; Burg, M E L van der

    2001-01-01

    Both weekly cisplatin chemotherapy and single agent topotecan have proven to be effective in recurrent ovarian cancer. Preclinical data show synergism between cisplatin and topotecan. Side effects for this combination are drug sequence dependent and predominantly haematologic. Since preclinical data suggest that Cremophor EL (CrEL), the formulation vehicle of paclitaxel, has a protective effect on haematological toxicity of cisplatin, CrEL was added to the combination cisplatin and topotecan. In this phase I study, escalating doses of oral topotecan administered on day 1, 2, 8, 9, 15, 16, 29, 30, 36, 37, 43, 44 were combined with weekly cisplatin 70 mg m−2d−1on day 1, 8, 15, 29, 36, 43 (scheme A) or with the presumably less myelotoxic sequence weekly cisplatin day 2, 9, 16, 30, 37, 44 (scheme B). In scheme C, CrEL 12 ml was administered prior to cisplatin in the sequence of Scheme A. 18 patients have received a total of 85 courses. In scheme A 4/10 patients, all treated with topotecan 0.45 mg m−2d−1, experienced DLT: 1 patient had vomiting grade 4, 1 patient had grade 4 neutropenia >5 days, 1 patient had >2 weeks delay due to thrombocytopenia and 1 patient due to neutropenia. Both patients in scheme B (topotecan 0.45 mg m−2d−1) had DLT due to a delay > 2 weeks because of prolonged haematological toxicity. No DLT was observed in the first 3 patients in scheme C (topotecan 0.45 mg m−2d−1). However, 2 out of 3 patients treated at dose level topotecan 0.60 mg m−2d−1in scheme C experienced DLT due to >2 weeks delay because of persistent thrombocytopenia or neutropenia. We conclude that there is a modest clinical effect of CrEL on haematological toxicity for this cisplatin-based combination regimen, which seems to reduce these side effects but does not really enable an increase of the oral topotecan dose. © 2001 Cancer Research Campaign  http://www.bjcancer.com PMID:11710824

  9. Evaluation of a low-dose CT protocol with oral contrast for assessment of acute appendicitis.

    PubMed

    Platon, Alexandra; Jlassi, Helmi; Rutschmann, Olivier T; Becker, Christoph D; Verdun, Francis R; Gervaz, Pascal; Poletti, Pierre-Alexandre

    2009-02-01

    The aim of this study was to evaluate a low-dose CT with oral contrast medium (LDCT) for the diagnosis of acute appendicitis and compare its performance with standard-dose i.v. contrast-enhanced CT (standard CT) according to patients' BMIs. Eighty-six consecutive patients admitted with suspicion of acute appendicitis underwent LDCT (30 mAs), followed by standard CT (180 mAs). Both examinations were reviewed by two experienced radiologists for direct and indirect signs of appendicitis. Clinical and surgical follow-up was considered as the reference standard. Appendicitis was confirmed by surgery in 37 (43%) of the 86 patients. Twenty-nine (34%) patients eventually had an alternative discharge diagnosis to explain their abdominal pain. Clinical and biological follow-up was uneventful in 20 (23%) patients. LDCT and standard CT had the same sensitivity (100%, 33/33) and specificity (98%, 45/46) to diagnose appendicitis in patients with a body mass index (BMI) >or= 18.5. In slim patients (BMI<18.5), sensitivity to diagnose appendicitis was 50% (2/4) for LDCT and 100% (4/4) for standard CT, while specificity was identical for both techniques (67%, 2/3). LDCT may play a role in the diagnostic workup of patients with a BMI >or= 18.5.

  10. Oral Mucosal Progenitor Cells Are Potently Immunosuppressive in a Dose-Independent Manner

    PubMed Central

    Davies, Lindsay C.; Lönnies, Helena; Locke, Matthew; Sundberg, Berit; Rosendahl, Kerstin; Götherström, Cecilia; Le Blanc, Katarina

    2012-01-01

    Oral mucosal lamina propria progenitor cells (OMLP-PCs) are a novel, clonally derived PC population of neural crest origin with the potential to differentiate down both mesenchymal and neuronal cell lineages. In this study we aimed to determine the immunological properties of OMLP-PCs and to establish whether they would be suitable candidates for allogeneic tissue engineering and in the treatment of immune-related diseases. OMLP-PCs demonstrated no inherent immunogenicity with insignificant expression of costimulatory molecules (CD40, CD80, CD86, CD154, and CD178) or human leukocyte antigen (HLA) class II. OMLP-PCs required 7 days of stimulation with interferon-γ (IFN-γ) to induce cell surface expression of HLA II. Mixed lymphocyte cultures and mitogen stimulation demonstrated the potent immunosuppressive capability of OMLP-PCs in a contact-independent manner. Complete inhibition of lymphocyte proliferation was seen at doses as low as 0.001% OMLP-PCs to responder lymphocytes, while annexin V staining confirmed that this immunosuppressive effect was not due to the induction of lymphocyte apoptosis. These data demonstrate, for the first time, that OMLP-PC immunomodulation, unlike that for mesenchymal stem cells, occurs via a dose- and HLA II–independent mechanism by the release of immunosuppressive soluble factors and suggests these cells may have wide ranging potential in future immune-related therapies. PMID:21988324

  11. Subchronic Oral Dose Toxicity of Freeze-dried Powder of Allomyrina dichotoma Larvae

    PubMed Central

    Noh, Jung-Ho; Yun, Eun-Young; Park, Heejin; Jung, Kyung-Jin; Hwang, Jae Sam; Jeong, Eun Ju; Moon, Kyoung-Sik

    2015-01-01

    The objective of this study was to investigate the toxicological information of freeze-dried powder from Allomyrina dichotoma (A. dichotoma) larvae as a food ingredient. The powder, suspended in distilled water, was administered once daily by oral gavage to four groups of Sprague-Dawley (SD) rats at dose levels of 0 (vehicle control), 250, 850, and 2500 mg/kg/day. After 13 wks of repeated administration, the standard toxicological parameters such as mortality, clinical signs, body weight, food consumption, ophthalmologic examination, clinical pathology, organ weights and macro/microscopic examination were applied for assessment of general toxicity. In addition, serum IgE and histamine levels were determined to evaluate allergenicity. The freeze-dried powder from A. dichotoma larvae did not produce treatmentrelated changes or findings in any toxicological parameters in either sex of any dosed groups except for slight increases in serum histamine levels at 2500 mg/kg/day. The changes were considered not to be adverse since the magnitude was minimal. In conclusion, the NOAEL (No Observed Adverse Effect Level) of the freeze-dried powder from A. dichotoma larvae was determined to be 2500 mg/kg/day or more in both sexes of SD rats and it is considered a candidate to be edible material. PMID:25874035

  12. Macrophage activity and histopathology of the lymphohematopoietic organs in male Wistar rats orally exposed to single or mixed pesticides.

    PubMed

    De Camargo, Marcela Rodrigues; Barbisan, Luís Fernando; Martinez, Meire França; Da Silva Franchi, Carla Adriene; De Camargo, João Lauro Viana; Spinardi-Barbisan, Ana Lúcia Tozzi

    2013-01-01

    The noxious effects of low or effective dose exposure to single or mixed pesticides on macrophage activity and the lymphohematopoietic organs were investigated. Male Wistar rats were orally exposed to dichlorvos, dicofol, endosulfan, dieldrin and permethrin, either as single or combined mixtures during a 28-day study containing eight groups: one group received a semipurified diet (non-treated); two groups received a semipurified diet containing low dose mixture (dieldrin 0.025 mg/kg, endosulfan, 0.6 mg/kg, dicofol 0.22 mg/kg, dichlorvos 0.23 mg/kg, permethrin 5 mg/kg) or an effective dose mixture (dichlorvos 2.3 mg/kg, dicofol 2.5 mg/kg, endosulfan 2.9 mg/kg, dieldrin 0.05 mg/kg and permethrin 25.0 mg/kg), respectively; the other five groups received a semipurified diet containing each single pesticide in effective doses. At sacrifice, the thymus, spleen, mesenteric lymph nodes, Payer's patches and bone marrow were removed for histological analysis. Peritoneal macrophages were obtained to determine the phagocytosis and spreading indexes and tumoral necrosis factor alpha (TNF-α), nitric oxide (NO) and H₂O₂ production. Exposure to pesticide mixtures did not alter the percentage of macrophage phagocytosis and spreading, TNF-α production or the NO and H₂O₂ release when compared to the non-treated group. Neither was there any apparent evidence that a pesticide mixture at low or effective doses altered the histological structure of the lymphohematopoietic organs. The findings indicate that short-term treatment with pesticide mixtures did not induce an apparent immunotoxic effect in male Wistar rats.

  13. [Effect of low doses of oral pamidronate (APD) on the calcemia of osteopenic or osteoporotic patients].

    PubMed

    Roldan, E J; Kerzberg, E M; Castelli, G; Lloret, A P

    1996-01-01

    Oral pamidronate (APD) at high doses (400-900 mg/day) is employed as antiresorptive agent for the treatment of Paget's disease. In some occasions hypocalcemia may occur, and is interpreted as a relative overdosage. To avoid this complication and the consequent PTH release, supplementation with calcium salts is recommended. In osteoporotic syndromes, APD is prescribed at a lower dosage (200 mg/day) and currently calcium or vitamin D are also systematically added. But at this low dose the antiresorptive activity is partial and transient. In order to observe the effects on calcemia of multiple therapy, data from 129 postmenopausal women with the diagnosis of osteopenia or osteoporosis treated with 200 mg/day of APD soft capsules during 6-10 months, were gathered retrospectively. The first group (n: 13) received APD alone; the second group was supplemented with 1 g/day calcium salts (n: 61); the third group received 0.015-0.025 mg/day vitamina D (n: 10); and the fourth received both calcium plus vitamin D (n: 45). In samples of 24 h, urine, calcium, creatinine, hydroxyproline, and serum total calcium were measured before and after therapy. No hypocalcemia was detected. All groups, except the one treated with APD alone, showed a significant trend to increase their calcemia values between normal ranges (Table 1, 2). Only in one patient treated with APD + Ca + vitamin D, hypercalcemia was detected. Measuring HOP/Cr and Ca/Cr in urine as resorption markers, showed that 27% of the APD + Ca group and 33% of the APD + Ca + vitamin D group showed scant or any repercussion on mentioned resorption indexes, meaning that the response to APD could be hindered in those cases. In conclusion, while using low doses of oral APD, calcium salts should not be systematically recommended. There is no trend to hypocalcemia. Furthermore, calcium salts may favor drug interactions and so induce digestive side effects or poor responses. Calcium supplementation should be prescribed only on the

  14. Clinical Efficacy of a Single Two Gram Dose of Azithromycin Extended Release for Male Patients with Urethritis

    PubMed Central

    Takahashi, Satoshi; Kiyota, Hiroshi; Ito, Shin; Iwasawa, Akihiko; Hiyama, Yoshiki; Uehara, Teruhisa; Ichihara, Koji; Hashimoto, Jiro; Masumori, Naoya; Sunaoshi, Kenichi; Takeda, Koichi; Suzuki, Nobukazu; Hosobe, Takahide; Goto, Hirokazu; Suzuki, Hidenori; Onodera, Shoichi

    2014-01-01

    To clarify the clinical efficacy of a single oral 2 g dose of azithromycin extended-release for heterosexual male patients with urethritis, and the current antimicrobial sensitivity of Neisseria gonorrhoeae to azithromycin, a prospective clinical trial was conducted from 2011–2013. In patients with gonococcal urethritis, the eradication rate was 90.9% (30 of 33). The susceptibility rates of isolated Neisseria gonorrhoeae strains to ceftriaxone, spectinomycin, cefixime and azithromycin were 100%, 100%, 95.3% (41/43) and 37.2% (16/43), respectively. In the patients with nongonococcal urethritis, the eradication rate was 90.0% (45 of 50). The microbiological eradication rates for the pathogens were 90.9% (30/33) for Neisseria gonorrhoeae, 91.5% (43/47) for Chlamydia trachomatis, 71.4% (5/7) for Mycoplasma genitalium, and 100% (13/13) for Ureaplasma urealyticum. The main adverse event was diarrhea and its manifestation rate was 35.2% (32 of 120). The symptom of diarrhea was mostly temporary and resolved spontaneously. The conclusion was that the treatment regimen with a single oral 2 g dose of azithromycin extended-release would be effective for patients with urethritis. However, the antimicrobial susceptibilities of Neisseria gonorrhoeae and Mycoplasma genitalium should be carefully monitored because of possible treatment failure. PMID:27025738

  15. Ochratoxin A induces oxidative DNA damage in liver and kidney after oral dosing to rats.

    PubMed

    Kamp, Hennicke G; Eisenbrand, Gerhard; Janzowski, Christine; Kiossev, Jetchko; Latendresse, John R; Schlatter, Josef; Turesky, Robert J

    2005-12-01

    The nephrotoxic/carcinogenic mycotoxin ochratoxin A (OTA) occurs as a contaminant in food and feed and may be linked to human endemic Balkan nephropathy. The mechanism of OTA-derived carcinogenicity is still under debate, since reactive metabolites of OTA and DNA adducts have not been unambiguously identified. Oxidative DNA damage, however, has been observed in vitro after incubation of mammalian cells with OTA. In this study, we investigated whether OTA induces oxidative DNA damage in vivo as well. Male F344 rats were dosed with 0, 0.03, 0.1, 0.3 mg/kg bw per day OTA for 4 wk (gavage, 7 days/wk, five animals per dose group). Subsequently, oxidative DNA damage was determined in liver and kidney by the comet assay (single cell gel electrophoresis) with/without use of the repair enzyme formamido-pyrimidine-DNA-glycosylase (FPG). The administration of OTA had no effect on basic DNA damage (determined without FPG); however, OTA-mediated oxidative damage was detected with FPG treatment in kidney and liver DNA of all dose groups. Since the doses were in a range that had caused kidney tumors in a 2-year carcinogenicity study with rats, the oxidative DNA damage induced by OTA may help to explain its mechanism of carcinogenicity. For the selective induction of tumors in the kidney, increased oxidative stress in connection with severe cytotoxicity and increased cell proliferation might represent driving factors.

  16. Single-dose rasburicase 6 mg in the management of tumor lysis syndrome in adults.

    PubMed

    McDonnell, Anne M; Lenz, Kristi L; Frei-Lahr, Debra A; Hayslip, John; Hall, Philip D

    2006-06-01

    Rasburicase is currently approved at a dosage of 0.15-0.2 mg/kg once/day for 5 days in pediatric patients with cancer to lower plasma uric acid concentrations and manage tumor lysis syndrome (TLS). Information on rasburicase dosing in adults is limited, with some data on using rasburicase as a single dose instead of multiple daily doses. Therefore, we evaluated the efficacy of a single dose of rasburicase for preventing or managing TLS in adults. We collected retrospective data for 11 adults with hematologic malignancies who received a single 6-mg dose of rasburicase. All patients received intravenous hydration with urinary alkalinization and allopurinol; however, due to adverse reactions, two patients received short courses of allopurinol. Only patients at high risk for TLS (e.g., large tumor burden, increasing uric acid concentration) or those with TLS received rasburicase. The single dose of rasburicase 6 mg resulted in a median 0.0773-mg/kg dose (range 0.0232-0.1361 mg/kg). The single 6-mg dose rapidly lowered uric acid concentrations in 10 of the 11 patients. The median uric acid concentration of 11.7 mg/dl (range 7.4-17.4 mg/dl) declined to 2.0 mg/dl (range 0.5-15.4 mg/dl) within a day after rasburicase administration (p=0.022). In these 10 patients, uric acid concentrations remained low despite subsequent chemotherapy, and none required additional rasburicase doses. The only patient who did not respond to the single 6-mg rasburicase dose was a morbidly obese man (259 kg, body mass index 87 kg/m2) who subsequently responded to an additional dose of rasburicase 12 mg. These results warrant further investigation of a single 6-mg dose of rasburicase in adults with TLS or at high-risk for developing TLS.

  17. Application of physiologically-based toxicokinetic modelling in oral-to-dermal extrapolation of threshold doses of cosmetic ingredients.

    PubMed

    Gajewska, M; Worth, A; Urani, C; Briesen, H; Schramm, K-W

    2014-06-16

    The application of physiologically based toxicokinetic (PBTK) modelling in route-to-route (RtR) extrapolation of three cosmetic ingredients: coumarin, hydroquinone and caffeine is shown in this study. In particular, the oral no-observed-adverse-effect-level (NOAEL) doses of these chemicals are extrapolated to their corresponding dermal values by comparing the internal concentrations resulting from oral and dermal exposure scenarios. The PBTK model structure has been constructed to give a good simulation performance of biochemical processes within the human body. The model parameters are calibrated based on oral and dermal experimental data for the Caucasian population available in the literature. Particular attention is given to modelling the absorption stage (skin and gastrointestinal tract) in the form of several sub-compartments. This gives better model prediction results when compared to those of a PBTK model with a simpler structure of the absorption barrier. In addition, the role of quantitative structure-property relationships (QSPRs) in predicting skin penetration is evaluated for the three substances with a view to incorporating QSPR-predicted penetration parameters in the PBTK model when experimental values are lacking. Finally, PBTK modelling is used, first to extrapolate oral NOAEL doses derived from rat studies to humans, and then to simulate internal systemic/liver concentrations - Area Under Curve (AUC) and peak concentration - resulting from specified dermal and oral exposure conditions. Based on these simulations, AUC-based dermal thresholds for the three case study compounds are derived and compared with the experimentally obtained oral threshold (NOAEL) values.

  18. Dose fractionation and single subject studies in PET

    NASA Astrophysics Data System (ADS)

    Balakrishnan, Karthikayan

    Conventional positron emission tomography (PET) for cognitive brain studies typically relies on information collected from the distribution of decays following an injection of 15O-labeled water. The number of injections that can be administered to the subject are constrained by radiation dose to the subject and total length of the PET scan. The standard protocol involves 8--10 injections of H152O separated by approximately 5--7 half-lives of 15O. The number of activation conditions that can be realistically studied in a standard PET session is between 8 and 10. This work investigates the physiological response of a simulated subject to H152O injections that are administered in small doses (1--5 mCi) with short inter-injection intervals (40--180 seconds). A larger number of activation conditions are presented to the subject with a wider variation in the activation paradigm. Repeat conditions are studies. Signal averaging methods are feasible with this method of dose administration. Sinograms from scans with similar activation conditions are summed together before reconstruction. The signal in the primary activation region of the brain is shown to increase while suppressing the contribution of secondary activation regions in the brain. The contrast of the final image is similarly increased which leads to easier identification of the primary activation region. An automated H152O -production unit controlled by a PC running LabView software was developed to produce the dose required for the injection sequence by controlling the flow of H152O -vapor that diffuses across a semi-permeable membrane into saline. The unit is capable of producing H152O rapidly for both the standard and the proposed dose administration methods. The system also detects the bolus arrival time at the subject's lungs using a small external plastic detector. Activation sequence commences with the rise in radioactivity observed by the detector. The simulations indicate that inter-injection intervals

  19. Tolerance of young infants to a single, large dose of vitamin A: a randomized community trial in Nepal.

    PubMed

    West, K P; Khatry, S K; LeClerq, S C; Adhikari, R; See, L; Katz, J; Shrestha, S R; Pradhan, E K; Pokhrel, R P; Sommer, A

    1992-01-01

    A randomized, double-masked trial was carried out in rural Nepal to investigate the incidence and severity of acute side-effects among neonates ( < 1 month of age) and infants aged 1-6 months who received a large, oral dose of vitamin A (15,000 retinol equivalents (RE) (50,000 IU) and 30,000 RE (100,000 IU), respectively) or placebo (75 RE (250 IU) and 150 RE (500 IU), respectively) in oil. Infants (vitamin A group, n = 1461; controls, n = 1379) were assessed for vomiting, loose stools, fever, and irritability during the 24 hours before and after dosing. Fontanelles were palpated 24 hours after dosing. Neonates exhibited no excess risk of adverse side-effects after receiving 15,000 RE. Compared with controls the older infants who ingested 30,000 RE had a 1.6% excess rate of vomiting (95% confidence interval (CI): 0.2-3.0%) and a 0.5% excess rate (95% CI: -0.1 to 1.1%) in the occurrence of bulging fontanelles. There were no other significant differences in the older infants. The controlled, periodic distribution of a single 15,000 RE dose of vitamin A therefore confers no apparent acute risk to young infants; a 30,000 RE dose is associated with a minimum risk of transient, acute side-effects. PMID:1486669

  20. Tolerance to effects of high-dose oral δ9-tetrahydrocannabinol and plasma cannabinoid concentrations in male daily cannabis smokers.

    PubMed

    Gorelick, David A; Goodwin, Robert S; Schwilke, Eugene; Schwope, David M; Darwin, William D; Kelly, Deanna L; McMahon, Robert P; Liu, Fang; Ortemann-Renon, Catherine; Bonnet, Denis; Huestis, Marilyn A

    2013-01-01

    Oral cannabinoids are taken for medicinal or recreational purposes, yet little is known about tolerance to their effects after high-dose extended exposure. The development of tolerance to effects of around-the-clock oral synthetic Δ9-tetrahydrocannabinol (THC) (20 mg every 3.5-6 h) was evaluated in 13 healthy male daily cannabis smokers residing on a secure research unit: 40 mg on Day 1; 100 mg on Days 2-4; 120 mg on Days 5-6. Systolic and diastolic blood pressure (BP), heart rate, and symptoms of subjective intoxication (100 mm visual-analogue scales, VAS) were assessed the morning of Day 1 (before any oral THC), and on Days 2, 4 and 6, every 30 min for 3 h after the first morning THC dose. Morning subjective intoxication ratings increased from Days 1 to 2, and then declined on Days 4 and 6. The morning THC dose increased intoxication ratings on Day 2, but had less effect on Days 4 and 6, a pattern consistent with tolerance. THC lowered BP and increased heart rate over the six days. Plasma THC and 11-OH-THC concentrations increased significantly over the first five days of dosing. Six days of around-the-clock, oral THC produced tolerance to subjective intoxication, but not to cardiovascular effects. PMID:23074216

  1. Survival patterns in white-tailed and mule deer after oral inoculation with a standardized, conspecific prion dose.

    PubMed

    Miller, Michael W; Wolfe, Lisa L; Sirochman, Tracey M; Sirochman, Michael A; Jewell, Jean E; Williams, Elizabeth S

    2012-04-01

    We orally inoculated white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus) with a standardized, conspecific prion dose and collected biologic samples throughout the disease course. Mule deer (PRNP genotype 225SS) and PRNP genotype 96GG white-tailed deer succumbed along similar trajectories, but 96GS- and 96SS-genotype individuals tended to survive longer.

  2. Effects of a single dose of menadione on the intestinal calcium absorption and associated variables.

    PubMed

    Marchionatti, Ana M; Díaz de Barboza, Gabriela E; Centeno, Viviana A; Alisio, Arturo E; Tolosa de Talamoni, Nori G

    2003-08-01

    The effect of a single large dose of menadione on intestinal calcium absorption and associated variables was investigated in chicks fed a normal diet. The data show that 2.5 micro mol of menadione/kg of b.w. causes inhibition of calcium transfer from lumen-to-blood within 30 min. This effect seems to be related to oxidative stress provoked by menadione as judged by glutathione depletion and an increment in the total carbonyl group content produced at the same time. Two enzymes presumably involved in calcium transcellular movement, such as alkaline phosphatase, located in the brush border membrane, and Ca(2+)- pump ATPase, which sits in the basolateral membrane, were also inhibited. The enzyme inhibition could be due to alterations caused by the appearance of free hydroxyl groups, which are triggered by glutathione depletion. Addition of glutathione monoester to the duodenal loop caused reversion of the menadione effect on both intestinal calcium absorption and alkaline phosphatase activity. In conclusion, menadione shifts the balance of oxidative and reductive processes in the enterocyte towards oxidation causing deleterious effects on intestinal Ca(2+) absorption and associated variables, which could be prevented by administration of oral glutathione monoester. PMID:12948877

  3. Effects of a single dose of menadione on the intestinal calcium absorption and associated variables.

    PubMed

    Marchionatti, Ana M; Díaz de Barboza, Gabriela E; Centeno, Viviana A; Alisio, Arturo E; Tolosa de Talamoni, Nori G

    2003-08-01

    The effect of a single large dose of menadione on intestinal calcium absorption and associated variables was investigated in chicks fed a normal diet. The data show that 2.5 micro mol of menadione/kg of b.w. causes inhibition of calcium transfer from lumen-to-blood within 30 min. This effect seems to be related to oxidative stress provoked by menadione as judged by glutathione depletion and an increment in the total carbonyl group content produced at the same time. Two enzymes presumably involved in calcium transcellular movement, such as alkaline phosphatase, located in the brush border membrane, and Ca(2+)- pump ATPase, which sits in the basolateral membrane, were also inhibited. The enzyme inhibition could be due to alterations caused by the appearance of free hydroxyl groups, which are triggered by glutathione depletion. Addition of glutathione monoester to the duodenal loop caused reversion of the menadione effect on both intestinal calcium absorption and alkaline phosphatase activity. In conclusion, menadione shifts the balance of oxidative and reductive processes in the enterocyte towards oxidation causing deleterious effects on intestinal Ca(2+) absorption and associated variables, which could be prevented by administration of oral glutathione monoester.

  4. Split-Dose Polyethylene Glycol Is Superior to Single Dose for Colonoscopy Preparation: Results of a Randomized Controlled Trial

    PubMed Central

    Mohamed, Rachid; Hilsden, Robert J.; Dube, Catherine; Rostom, Alaa

    2016-01-01

    Background. The efficacy of colonoscopy in detecting abnormalities within the colon is highly dependent on the adequacy of the bowel preparation. The objective of this study was to compare the efficacy, safety, and tolerability of PEG lavage and split-dose PEG lavage with specific emphasis on the cleanliness of the right colon. Methods. The study was a prospective, randomized, two-arm, controlled trial of 237 patients. Patients between the age of 50 and 75 years were referred to an outpatient university screening clinic for colonoscopy. Patients were allocated to receive either a single 4 L PEG lavage or a split-dose PEG lavage. Results. Overall, the bowel preparation was superior in the split-dose group compared with the single-dose group (mean Ottawa score 3.50 ± 2.89 versus 5.96 ± 3.53; P < 0.05) and resulted in less overall fluid in the colon. This effect was observed across all segments of the colon assessed. Conclusions. The current study supports use of a split-dose PEG lavage over a single large volume lavage for superior bowel cleanliness, which may improve polyp detection. This trial is registered with ClinicalTrials.gov identifier NCT01610856. PMID:27446836

  5. A bounding estimate of neutron dose based on measured photon dose around single pass reactors at the Hanford site.

    PubMed

    Taulbee, Timothy D; Glover, Samuel E; Macievic, Gregory V; Hunacek, Mickey; Smith, Cheryl; DeBord, Gary W; Morris, Donald; Fix, Jack

    2010-07-01

    Neutron and photon radiation survey records have been used to evaluate and develop a neutron to photon (NP) ratio to reconstruct neutron doses to workers around Hanford's single pass reactors that operated from 1945 to 1972. A total of 5,773 paired neutron and photon measurements extracted from 57 boxes of survey records were used in the development of the NP ratio. The development of the NP ratio enables the use of the recorded dose from an individual's photon dosimeter badge to be used to estimate the unmonitored neutron dose. The Pearson rank correlation between the neutron and photon measurements was 0.71. The NP ratio best fit a lognormal distribution with a geometric mean (GM) of 0.8, a geometric standard deviation (GSD) of 2.95, and the upper 95 th % of this distribution was 4.75. An estimate of the neutron dose based on this NP ratio is considered bounding due to evidence that up to 70% of the total photon exposure received by workers around the single pass reactors occurs during shutdown maintenance and refueling activities when there is no significant neutron exposure. Thus when this NP ratio is applied to the total measured photon dose from an individual film badge dosimeter, the resulting neutron dose is considered bounded.

  6. SINGLE VERSUS MULTI-DOSE ANTIBIOTIC PROPHYLAXIS FOR PELVIC ORGAN PROLAPSE SURGERY WITH GRAFT/MESH

    PubMed Central

    Andy, Uduak U.; Harvie, Heidi S.; Ackenbom, Mary F.; Arya, Lily A.

    2015-01-01

    Objective To compare the risk of postoperative infections in women who receive single-dose versus multi-dose prophylactic antibiotic regimen during prolapse surgery with mesh/graft. Study Design Retrospective cohort study of 460 women who underwent prolapse surgery with mesh/graft. We compared women who received a single-dose prophylactic antibiotic regimen to those who received a multi-dose regimen. The primary outcome was the presence of any post-operative infection, defined as the presence of any of the following infections: urinary tract infection (UTI), fever, wound or trocar site infection, mesh infection or pelvic abscess. Associations between prophylactic antibiotic regimen and post-operative infections were estimated using univariable and multivariable analysis. Results Rate of any postoperative infection was similar between the single-dose and multi-dose groups (19% vs. 16%, p=0.50). Rate of UTI was significantly higher in the single-dose compared to the multi-dose group (13% vs. 7%, p=0.03). On multivariable analysis, after controlling for vaginal route of surgery, the odds of UTI was not significantly different between groups (OR 0.59, 95% CI 0.27, 1.26). Conclusion A single dose antibiotic regimen is sufficient for prophylaxis against post-operative infections in women undergoing prolapse surgery with graft/mesh. PMID:25126979

  7. Association of single nucleotide polymorphisms in cell cycle regulatory genes with oral cancer susceptibility.

    PubMed

    Murali, Abitha; Nalinakumari, K R; Thomas, Shaji; Kannan, S

    2014-09-01

    Alterations in the regulation of the cell cycle are strongly linked to tumorigenesis, so genetic variants in genes critical to control of the cycle are good candidates to have their association with susceptibility to oral cancer assessed. In this hospital-based, case-control study of 445 patients who had been newly-diagnosed with oral cancer and 449 unaffected controls, we used a multigenic approach to examine the associations among a panel of 10 selected polymorphisms in the pathway of the cell cycle that were possibly susceptible to oral cancer. Six of 9 single nucleotide polymorphisms in the cell cycle showed significant risks for oral cancer, the highest risk being evident for p27 (rs34329; Odds ratio 3.05, 95% CI 2.12 to 4.40). A significant risk of oral cancer was also evident for individual polymorphisms of cyclin E (rs1406), cyclin H (rs3093816), cyclin D1-1 (rs647451), cyclin D2 (rs3217901) and Rb1-2 (rs3092904). The risk of oral cancer increased significantly as the number of unfavourable genotypes in the pathway increased, and so the results point to a stronger combined effect of polymorphisms in important cell cycle regulatory genes on predisposition to oral cancer. PMID:24947332

  8. Low-Dose Pharmacokinetics and Oral Bioavailability of Dichloroacetate in Naive and GST-zeta Depleted Rats

    SciTech Connect

    Saghir, Shakil A.; Schultz, Irv R. )

    2002-01-01

    Pharmacokinetics of dichloroacetate (DCA) in naive and glutathione-S-transferase-zeta (GSTzeta) depleted rats was studied at doses approaching human daily exposure levels. In vitro metabolism of DCA by rat and human liver cytosol was also compared. Jugular vein cannulated male Fischer-344 rats were administered (i.v or gavage) with graded doses of DCA ranging from 0.05-20 mg/kg and time-course blood samples collected from the cannula. GSTzeta was depleted by exposing rats to DCA (0.2 g/L DCA) in drinking water for 7 days. Elimination of DCA by naive rats was so rapid that only the 1-20 mg/kg i.v. and 5 and 20 mg/kg gavage doses provided plasma concentrations above the method detection limit. GSTzeta depletion slowed DCA elimination from plasma allowing kinetic analysis of doses as low as 0.05 mg/kg. DCA elimination was strongly dose-dependent in the naive rats with total body clearance declining with increasing dose. In the GSTzeta depleted rats, the pharmacokinetics became line ar at doses No.1 mg/kg. All oral doses were rapidly absorbed without any lag time. At higher oral doses (?5 mg/kg in GSTzeta depleted and?20 mg/kg in naive), secondary peaks in the plasma concentration appeared long after the completion of the initial absorption phase. Virtually all the dose was eliminated through metabolic clearance; the rate of urinary elimination of DCA was < 1 ml h-1kg-1. A maximum of 1.0?0.3% dose was recovered in urine within 24 h in the GSTzeta depleted rats dosed i.v. with 20 mg/kg. The rate of in vitro metabolism of DCA by human cytosol was statistically similar to the GSTzeta depleted rats (p > 0.3), which supported the use of GSTzeta depleted rats as a model for assessing kinetics of DCA in humans. Oral bioavailability of DCA was 0-13% in naive and 14-75% in GSTzeta depleted rats. Oral bioavailability of DCA to humans through consumption of drinking water was predicted to be a maximum of 0.05%.

  9. Fixed-Dose Combination Gel of Adapalene and Benzoyl Peroxide plus Doxycycline 100 mg versus Oral Isotretinoin for the Treatment of Severe Acne: Efficacy and Cost Analysis

    PubMed Central

    Penna, Pete; Meckfessel, Matthew H.; Preston, Norman

    2014-01-01

    Background Acne vulgaris is a chronic skin disease with a high prevalence. Left untreated or inadequately treated, acne vulgaris can lead to psychological and physical scarring, as well as to unnecessary medical expenses. Oral isotretinoin is an effective treatment for severe resistant nodular and conglobate acne vulgaris. A regimen consisting of a fixed-dose combination of adapalene and benzoyl peroxide gel, 0.1%/2.5% (A-BPO) with oral doxycycline 100 mg (A-BPO/D) has been demonstrated to be efficacious and well tolerated in patients with severe acne and may be an alternative to oral isotretinoin for some patients with severe acne. Objective The objective of this analysis was to compare the relative efficacy and associated costs of A-BPO/D versus oral isotretinoin. Methods In this analysis, comparisons of relative efficacy were made using previously published studies involving similar patient populations with severe acne that warrant the use of oral isotretinoin. The pricing for oral doxycycline and oral isotretinoin was estimated based on the maximum allowable cost from 9 states, and the pricing for A-BPO was calculated as the range between the average wholesale price and the wholesale acquisition cost. For this analysis, 2 treatment models were generated to compare costs: (1) a basic treatment model that examined the costs of an initial regimen of either A-BPO/D or oral isotretinoin without considering probable outcomes, and (2) a long-term model that factored in likely treatment outcomes and subsequent treatments into associated costs. The basic treatment model assumed that patients would be prescribed a single regimen of A-BPO/D for 12 weeks or oral isotretinoin for 20 weeks. The long-term model considered the probability of each treatment successfully managing patients' acne, as well as likely additional regimens of A-BPO monotherapy or an additional regimen of oral isotretinoin. As a result of different treatment durations, the costs for each treatment were

  10. Evaluation of changes in serum chemistry in association with feed withdrawal or high dose oral gavage with Dextran Sodium Sulfate (DSS) induced gut leakage in broiler chickens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dextran sodium sulfate (DSS) has been shown to be effective at inducing enteric inflammation in broiler chickens, resulting in increased leakage of orally administered fluorescein isothiocyanate dextran to circulation. In a previous study, two doses of DSS (0.45g/dose) administered as oral gavage re...

  11. Development of an oral solid dispersion formulation for use in low-dose metronomic chemotherapy of paclitaxel.

    PubMed

    Moes, Johannes; Koolen, Stijn; Huitema, Alwin; Schellens, Jan; Beijnen, Jos; Nuijen, Bastiaan

    2013-01-01

    For the clinical development of low-dose metronomic (LDM) chemotherapy of paclitaxel, oral administration is vital. However, the development of an oral formulation is difficult due to paclitaxel's low oral bioavailability, caused by its low permeability and low solubility. We increased the oral bioavailability of paclitaxel by combining a pharmacokinetic booster, ritonavir, with a new oral solid dispersion formulation of paclitaxel. The combined use of Hansen solubility parameters and dissolution experiments resulted in the development of a solid dispersion formulation containing 1/11 w/w paclitaxel, 9/11 w/w polyvinylpyrrolidone (PVP) K30, and 1/11 w/w sodium lauryl sulfate (SLS). Analysis of the solid dispersion formulation by X-ray diffraction, Fourier transform infrared (FT-IR) spectroscopy, and modulated differential scanning calorimetry (mDSC) confirmed the amorphous nature of paclitaxel and the fine dispersion of paclitaxel in the matrix of PVP-K30 and SLS. Furthermore, in vitro tests showed a major increase in the apparent solubility and dissolution rate of paclitaxel. To test the clinical significance of these findings, the solid dispersion formulation of paclitaxel (ModraPac001 10mg capsule) was compared to the paclitaxel premix solution in four patients with advanced cancer. Although the mean systemic exposure to paclitaxel after oral administration of the solid dispersion formulation was slightly lower compared to the paclitaxel premix solution (190±63.1ng/mLh for vs. 247±100ng/mLh), the systemic exposure to paclitaxel is clinically relevant [1,2]. In addition to this, the favorable pharmaceutical characteristics, for example, neutral taste, dosing accuracy, and the 2-year ambient shelf life, make the ModraPac001 10mg capsule an attractive candidate for oral paclitaxel chemotherapy. Currently, the ModraPac001 formulation is applied in the first clinical trial with oral LDM chemotherapy of paclitaxel.

  12. α- and γ-tocopherol levels in Nelore steer blood plasma after a single oral treatment of soybean oil deodorizer distillate (SODD).

    PubMed

    Borher, J R Z; Gonçalves, L A G; de Felício, P E

    2002-07-01

    The paper presents a study on the effect of a treatment of steers with a single oral dose of soybean oil deodorizer distillate (SODD) on the α- and γ-tocopherol blood plasma concentrations. SODD containing 1.95% of α-tocopherol and 8.45% of γ-tocopherol in doses of 0.75, 1.50 or 2.25g/kg live weight was used on nine 2-year-old Nelore (Bos indicus) steers to promote increases in the plasma concentration of vitamin E. Tocopherol analyses were performed by HPLC on a C18 column, using a UV detector. The results showed that a single oral treatment of steers with SODD produces significant increases in plasma α- and γ-tocopherol levels. The vitamin E content was increased up to four times the initial content, showing the high capacity of SODD as a source of vitamin E for bovines in a single oral dose with the objective of increasing vitamin E blood plasma concentrations and, consequently, the levels in the tissues, as well. PMID:22060854

  13. Interoceptive conditioning in rats: effects of using a single training dose or a set of 5 different doses of nicotine.

    PubMed

    Pittenger, Steven T; Bevins, Rick A

    2013-12-01

    Interoceptive conditioning contributes to the tenacity of nicotine dependence. Previous research investigating nicotine as an interoceptive stimulus has typically employed administration of a single training dose of nicotine over an extended time. This approach has allowed for careful study of the nicotine stimulus. In humans, the nicotine stimulus is unlikely to be fixed across learning episodes. Thus, from a translational perspective, systematic variation of nicotine dose in training might better approximate interoceptive conditioning in humans. Notably, training with a class or set of discrete exteroceptive stimuli (e.g., different pictures of cars) produces interesting behavioral differences relative to training with a single stimulus. The present study sought to determine whether similar differences would occur if a set of nicotine stimuli were used in place of a single dose. To investigate this question, one group of male Sprague-Dawley rats was trained on a discriminated goal-tracking task with a set of nicotine doses (0.05, 0.125, 0.2, 0.275, and 0.35mg/kg). A second group received the standard protocol of training with a single nicotine dose (0.2mg/kg). On each nicotine session, there was intermittent access to liquid sucrose (26%) in a conditioning chamber. On intermixed saline sessions, sucrose was withheld. We examined acquisition, subsequent extinction, transfer of extinction, nicotine generalization, and mecamylamine blockade. Both groups reliably discriminated between nicotine and saline sessions, were sensitive to non-reinforcement, displayed transfer of extinction, demonstrated dose-dependent nicotine generalization, and responding was blocked by mecamylamine. There were no significant differences between the two groups. The unique nature of an interoceptive pharmacological stimulus and the challenges posed for studying the impact of training with a set of interoceptive stimuli are discussed.

  14. A 4-week Repeated dose Oral Toxicity Study of Mecasin in Sprague-Dawley Rats to Determine the Appropriate Doses for a 13-week, Repeated Toxicity Test

    PubMed Central

    Cha, Eunhye; Lee, Jongchul; Lee, Seongjin; Park, Manyong; Song, Inja; Son, Ilhong; Song, Bong-Keun; Kim, Dongwoung; Lee, Jongdeok

    2015-01-01

    Objectives: In this study, we investigated the 4-week repeated-dose oral toxicity of gami-jakyak gamcho buja decoction (Mecasin) to develop safe treatments. Methods: In order to investigate the 4-week oral toxicity of Mecasin, we administered Mecasin orally to rats. Sprague-Dawley (SD) rats were divided into four groups of five male and five female animals per group: group 1 being the control group and groups 2, 3, and 4 being the experimental groups. Doses of Mecasin of 500, 1,000, and 2,000 mg/kg of body weight were administered to the experimental groups, and a dose of normal saline solution of 10 mL/kg was administered to the control group. We examined the survival rate, weight, clinical signs, and gross findings for four weeks. This study was conducted under the approval of the Institutional Animal Ethics Committee. Results: No deaths occurred in any of the four groups. No significant changes in weights or food consumption between the control group and the experimental groups were observed. Serum biochemistry revealed that some groups showed significant decrease in inorganic phosphorus (IP) (P < 0.05). During necropsy on the rats, one abnormal macroscopic feature, a slight loss of fur, was observed in the mid dosage (1,000 mg/ kg) male group. No abnormalities were observed in any other rats. In histopathological findings, the tubular basophilia and cast of the kidney and extramedullary hematopoiesis of the spleen were found. However, those changes were minimal and had occurred naturally or sporadically. No other organ abnormalities were observed. Conclusion: During this 4-week, repeated, oral toxicity test of Mecasin in SD rats, no toxicity changes due to Mecasin were observed in any of the male or the female rats in the high dosage group. Thus, we suggest that the doses in a 13-week, repeated test should be 0, 500, 1,000, and 2,000 mg/kg respectively. PMID:26998389

  15. Dose-response relationships of oral habits associated with the risk of oral pre-malignant lesions among men who chew betel quid.

    PubMed

    Yen, Amy Ming-Fang; Chen, Shao-Ching; Chen, Tony Hsiu-Hsi

    2007-08-01

    Betel quid, cigarettes and alcohol are well-recognized risk factors for oral cancer. However, the combined effect of the frequency and duration of these oral habits on the risk for developing oral pre-malignancies among betel quid users has not been fully addressed. In this study, an oral screening programme for men chewing betel quid was carried out by well-trained dentists for early detection of oral pre-malignancy lesions. Using generalized logit model and proportional odds model, we found that, compared with the occasional user, the adjusted odds ratios of developing leukoplakia for men chewing one to 10 pieces of betel quid, 11-20 pieces, and more than 20 pieces per day were estimated as 2.14 (95% confidence interval [CI] 1.62-2.81), 2.99 (95% CI 2.06-4.27), and 5.37 (95% CI 3.76-7.47), respectively. The corresponding figures for erythroleukoplakia were 3.69 (95% CI 1.55-8.79), 13.78 (95% CI 5.76-32.98), and 36.64 (95% CI 15.94-84.16), respectively. Similar results were found while the duration was considered. The dose-response relationships were not as noteworthy for cigarette and alcohol drinking.

  16. Toxicity evaluation of zinc aluminium levodopa nanocomposite via oral route in repeated dose study

    NASA Astrophysics Data System (ADS)

    Kura, Aminu Umar; Cheah, Pike-See; Hussein, Mohd Zobir; Hassan, Zurina; Tengku Azmi, Tengku Ibrahim; Hussein, Nor Fuzina; Fakurazi, Sharida

    2014-05-01

    Nanotechnology, through nanomedicine, allowed drugs to be manipulated into nanoscale sizes for delivery to the different parts of the body, at the same time, retaining the valuable pharmacological properties of the drugs. However, efficient drug delivery and excellent release potential of these delivery systems may be hindered by possible untoward side effects. In this study, the sub-acute toxicity of oral zinc aluminium nanocomposite with and without levodopa was assessed using the Organization for Economic Co-operation and Development guidelines. No sign or symptom of toxicity was observed in orally treated rats with the nanocomposite at 5 and 500 mg/kg concentrations. Body weight gain, feeding, water intake, general survival and organosomatic index were not significantly different between control and treatment groups. Aspartate aminotransferase (AST) in 500 mg/kg levodopa nanocomposite (169 ± 30 U/L), 5 mg/kg levodopa nanocomposite (172 ± 49 U/L), and 500 mg/kg layered double hydroxides (LDH) nanocomposite (175 ± 25 U/L) were notably elevated compared to controls (143 ± 05 U/L); but the difference were not significant ( p > 0.05). However, the differences in aspartate aminotransferase/alanine aminotransferase (AST/ALT) ratio of 500 mg/kg levodopa nanocomposite (0.32 ± 0.12) and 500 mg/kg LDH nanocomposite (0.34 ± 0.12) were statistically significant ( p < 0.05) compared to the control (0.51 ± 0.07). Histology of the liver, spleen and brain was found to be of similar morphology in both control and experimental groups. The kidneys of 500-mg/kg-treated rats with levodopa nanocomposite and LDH nanocomposite were found to have slight inflammatory changes, notably leukocyte infiltration around the glomeruli. The ultra-structure of the neurons from the substantia nigra of nanocomposite-exposed group was similar to those receiving only normal saline. The observed result has suggested possible liver and renal toxicity in orally administered levodopa intercalated

  17. Short- and long-term hormonal effects of a single dose of 50 mg tamoxifen administered to normal males.

    PubMed

    Fauser, B C; Dony, J M; Doesburg, W H; Thomas, C M; Rolland, R

    1984-01-01

    To five potentially fertile males, a single dose of 50 mg tamoxifen was administered orally to explore the short- and long-term hormonal effects on the hypothalamic-pituitary-gonadal axis. Blood specimens were obtained through an integrated sampling technique for the first two hours after the intake of the drug. Then, samples were taken daily throughout one week, and twice weekly for the next two weeks. Hormone measurements of luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone and oestradiol were obtained by specific RIA. All the subjects showed different response patterns. No general characteristic of the hormonal changes in the investigated group could be given. A consistent correlation between the within-individual levels of gonadotrophin and sex steroid changes could not be observed. It is concluded, within the limits of the used experimental design, that in healthy males a single administration of tamoxifen does not result in consistent changes in serum levels of either gonadotrophins or sex steroid hormones.

  18. Evaluation of the bioequivalence and pharmacokinetics of two formulations of secnidazole after single oral administration in healthy volunteers.

    PubMed

    Zhu, De Qiu; Hu, Kai Li; Tao, Wei Xing; Feng, Liang; Duan, Hu; Jiang, Xin Guo; Chen, Jun

    2007-01-01

    The pharmacokinetic parameters of two oral formulations of a 1 g dose of secnidazole (CAS 3366-95-8, secnidazole tablet as reference and another capsule preparation as test) were compared in an open-label, randomized, single oral dose, two-period cross-over design in 18 healthy volunteers under fasting conditions. Plasma concentrations of secnidazole were measured by a validated HPLC chromatographic assay. The parametric 90% confidence intervals of the geometric mean values of the test/reference ratios were 91.9% to 105.9% (point estimate: 99.39%) for AUC(0-infinity), 92.7% to 104.4% (point estimate: 98.61%) for AUC(0-t), 97.6% to 107.1% (point estimate: 102.31%) for C(max), being within the acceptance criteria for bioequivalence (80%-125%). T(max) values were analyzed by the nonparametric Wilcoxon test and the difference was not statistically significant. Therefore, it is concluded that the test and reference secnidazole formulations are bioequivalent for both the extent and the rate of absorption. PMID:18193695

  19. Aeromonas hydrophila OmpW PLGA Nanoparticle Oral Vaccine Shows a Dose-Dependent Protective Immunity in Rohu (Labeo rohita)

    PubMed Central

    Dubey, Saurabh; Avadhani, Kiran; Mutalik, Srinivas; Sivadasan, Sangeetha Madambithara; Maiti, Biswajit; Paul, Joydeb; Girisha, Shivani Kallappa; Venugopal, Moleyur Nagarajappa; Mutoloki, Stephen; Evensen, Øystein; Karunasagar, Indrani; Munang’andu, Hetron Mweemba

    2016-01-01

    Aeromonas hydrophila is a Gram-negative bacterium that causes high mortality in different fish species and at different growth stages. Although vaccination has significantly contributed to the decline of disease outbreaks in aquaculture, the use of oral vaccines has lagged behind the injectable vaccines due to lack of proven efficacy, that being from primary immunization or by use of boost protocols. In this study, the outer membrane protein W (OmpW) of A. hydrophila was cloned, purified, and encapsulated in poly d,l-lactide-co-glycolic acid (PLGA) nanoparticles (NPs) for oral vaccination of rohu (Labeo rohita Hamilton). The physical properties of PLGA NPs encapsulating the recombinant OmpW (rOmpW) was characterized as having a diameter of 370–375 nm, encapsulation efficiency of 53% and −19.3 mV zeta potential. In vitro release of rOmpW was estimated at 34% within 48 h of incubation in phosphate-buffered saline. To evaluate the efficacy of the NP-rOmpW oral vaccine, two antigen doses were orally administered in rohu with a high antigen (HiAg) dose that had twice the amount of antigens compared to the low antigen (LoAg) dose. Antibody levels obtained after vaccination showed an antigen dose dependency in which fish from the HiAg group had higher antibody levels than those from the LoAg group. The antibody levels corresponded with post challenge survival proportions (PCSPs) and relative percent survival (RPS) in which the HiAg group had a higher PCSP and RPS than the LoAg group. Likewise, the ability to inhibit A. hydrophila growth on trypticase soy agar (TSA) by sera obtained from the HiAg group was higher than that from the LoAg group. Overall, data presented here shows that OmpW orally administered using PLGA NPs is protective against A. hydrophila infection with the level of protective immunity induced by oral vaccination being antigen dose-dependent. Future studies should seek to optimize the antigen dose and duration of oral immunization in rohu in order to

  20. Aeromonas hydrophila OmpW PLGA Nanoparticle Oral Vaccine Shows a Dose-Dependent Protective Immunity in Rohu (Labeo rohita).

    PubMed

    Dubey, Saurabh; Avadhani, Kiran; Mutalik, Srinivas; Sivadasan, Sangeetha Madambithara; Maiti, Biswajit; Paul, Joydeb; Girisha, Shivani Kallappa; Venugopal, Moleyur Nagarajappa; Mutoloki, Stephen; Evensen, Øystein; Karunasagar, Indrani; Munang'andu, Hetron Mweemba

    2016-01-01

    Aeromonas hydrophila is a Gram-negative bacterium that causes high mortality in different fish species and at different growth stages. Although vaccination has significantly contributed to the decline of disease outbreaks in aquaculture, the use of oral vaccines has lagged behind the injectable vaccines due to lack of proven efficacy, that being from primary immunization or by use of boost protocols. In this study, the outer membrane protein W (OmpW) of A. hydrophila was cloned, purified, and encapsulated in poly d,l-lactide-co-glycolic acid (PLGA) nanoparticles (NPs) for oral vaccination of rohu (Labeo rohita Hamilton). The physical properties of PLGA NPs encapsulating the recombinant OmpW (rOmpW) was characterized as having a diameter of 370-375 nm, encapsulation efficiency of 53% and -19.3 mV zeta potential. In vitro release of rOmpW was estimated at 34% within 48 h of incubation in phosphate-buffered saline. To evaluate the efficacy of the NP-rOmpW oral vaccine, two antigen doses were orally administered in rohu with a high antigen (HiAg) dose that had twice the amount of antigens compared to the low antigen (LoAg) dose. Antibody levels obtained after vaccination showed an antigen dose dependency in which fish from the HiAg group had higher antibody levels than those from the LoAg group. The antibody levels corresponded with post challenge survival proportions (PCSPs) and relative percent survival (RPS) in which the HiAg group had a higher PCSP and RPS than the LoAg group. Likewise, the ability to inhibit A. hydrophila growth on trypticase soy agar (TSA) by sera obtained from the HiAg group was higher than that from the LoAg group. Overall, data presented here shows that OmpW orally administered using PLGA NPs is protective against A. hydrophila infection with the level of protective immunity induced by oral vaccination being antigen dose-dependent. Future studies should seek to optimize the antigen dose and duration of oral immunization in rohu in order to

  1. Complex histopathologic response in rat kidney to oral β-myrcene: an unusual dose-related nephrosis and low-dose alpha2u-globulin nephropathy.

    PubMed

    Cesta, Mark F; Hard, Gordon C; Boyce, John T; Ryan, Michael J; Chan, Po C; Sills, Robert C

    2013-01-01

    Oral gavage studies with β-myrcene in male F344 rats showed a complex renal pathology comprising both alpha2u-globulin (α2u-g) nephropathy, an unusual nephrosis involving the outer stripe of outer medulla (OSOM), and an increased incidence of renal tubule tumors by 2 years. In the 90-day and 2-year studies, respectively, α2u-g nephropathy and linear papillary mineralization were observed in males at the two lower doses but were absent from the high dose. Nephrosis was characterized by dilation of the S3 tubules, nuclear enlargement (including karyomegaly), and luminal pyknotic cells, all in the outermost OSOM. Nephrosis was minimal at the higher doses in the 90-day study, but progressed to a severe grade in males dosed with 1,000 mg/kg for 2 years. Renal tubule tumors developed in treated groups with incidences up to 30% in the 250 and 500 mg/kg male dose groups. Tumors at the lower doses in males may have been associated with α2u-g nephropathy, while those at higher doses in both sexes may have been due to the nephrosis. Because β-myrcene induced a complex spectrum of renal pathology, the α2u-g nephropathy mechanism cannot be the sole mechanism of carcinogenesis in these rats.

  2. COMPARATIVE METABOLISM OF ARSENIC IN MICE AFTER A SINGLE OR REPEATED ORAL ADMINISTRATION OF ARSENATE

    EPA Science Inventory

    COMPARATIVE METABOLISM OF ARSENIC IN MICE AFTER A SINGLE OR REPEATED ORAL ADMINISTRATION OF ARSENATE
    Michael F. Hughes*1, Elaina M. Kenyon1, Brenda C. Edwards1, Carol T. Mitchell1, Luz Maria Del Razo2 and David J. Thomas1
    1US EPA, ORD, NHEERL, ETD, PKB, Research Triangle Pa...

  3. Marrow toxicity of fractionated vs. single dose total body irradiation is identical in a canine model

    SciTech Connect

    Storb, R.; Raff, R.F.; Graham, T.; Appelbaum, F.R.; Deeg, H.J.; Schuening, F.G.; Shulman, H.; Pepe, M. )

    1993-03-20

    The authors explored in dogs the marrow toxicity of single dose total body irradiation delivered from two opposing [sup 60]Co sources at a rate of 10 cGy/min and compared results to those seen with total body irradiation administered in 100 cGy fractions with minimum interfraction intervals of 6 hr. Dogs were not given marrow transplants. They found that 200 cGy single dose total body irradiation was sublethal, with 12 of 13 dogs showing hematopoietic recovery and survival. Seven of 21 dogs given 300 cGy single dose total body irradiation survived compared to 6 of 10 dogs given 300 cGy fractionated total body irradiation. One of 28 dogs given 400 cGy single dose total body irradiation survived compared to none of six given fractionated radiation. With granulocyte colony stimulating factor (GCSF) administered from day 0-21 after 400 cGy total body irradiation, most dogs survived with hematological recovery. Because of the almost uniform success with GCSF after 400 cGy single dose total body irradiation, a study of GCSF after 400 cGy fractionated total body irradiation was deemed not to be informative and, thus, not carried out. Additional comparisons between single dose and fractionated total body irradiation were carried out with GCSF administered after 500 and 600 cGy of total body irradiation. As with lower doses of total body irradiation, no significant survival differences were seen between the two modes of total body irradiation, and only 3 of 26 dogs studied survived with complete hematological recovery. Overall, therefore, survival among dogs given single dose total body irradiation was not different from that of dogs given fractionated total body irradiation (p = .67). Similarly, the slopes of the postirradiation declines of granulocyte and platelet counts and the rates of their recovery in surviving dogs given equal total doses of single versus fractionated total body irradiation were indistinguishable. 24 refs., 3 figs., 2 tabs.

  4. FV-162 is a novel, orally bioavailable, irreversible proteasome inhibitor with improved pharmacokinetics displaying preclinical efficacy with continuous daily dosing.

    PubMed

    Wang, Z; Dove, P; Wang, X; Shamas-Din, A; Li, Z; Nachman, A; Oh, Y J; Hurren, R; Ruschak, A; Climie, S; Press, B; Griffin, C; Undzys, E; Aman, A; Al-awar, R; Kay, L E; O'Neill, D; Trudel, S; Slassi, M; Schimmer, A D

    2015-01-01

    Approved proteasome inhibitors have advanced the treatment of multiple myeloma but are associated with serious toxicities, poor pharmacokinetics, and most with the inconvenience of intravenous administration. We therefore sought to identify novel orally bioavailable proteasome inhibitors with a continuous daily dosing schedule and improved therapeutic window using a unique drug discovery platform. We employed a fluorine-based medicinal chemistry technology to synthesize 14 novel analogs of epoxyketone-based proteasome inhibitors and screened them for their stability, ability to inhibit the chymotrypsin-like proteasome, and antimyeloma activity in vitro. The tolerability, pharmacokinetics, pharmacodynamic activity, and antimyeloma efficacy of our lead candidate were examined in NOD/SCID mice. We identified a tripeptide epoxyketone, FV-162, as a metabolically stable, potent proteasome inhibitor cytotoxic to human myeloma cell lines and primary myeloma cells. FV-162 had limited toxicity and was well tolerated on a continuous daily dosing schedule. Compared with the benchmark oral irreversible proteasome inhibitor, ONX-0192, FV-162 had a lower peak plasma concentration and longer half-life, resulting in a larger area under the curve (AUC). Oral FV-162 treatment induced rapid, irreversible inhibition of chymotrypsin-like proteasome activity in murine red blood cells and inhibited tumor growth in a myeloma xenograft model. Our data suggest that oral FV-162 with continuous daily dosing schedule displays a favorable safety, efficacy, and pharmacokinetic profile in vivo, identifying it as a promising lead for clinical evaluation in myeloma therapy.

  5. Quantitative oral dosing of water soluble and lipophilic contaminants in the Japanese medaka (Oryzias latipes).

    PubMed

    Schultz, I R; Reed, S; Pratt, A; Skillman, A D

    2007-02-01

    Quantitative oral dosing in fish can be challenging, particularly with water soluble contaminants, which can leach into the aquarium water prior to ingestion. We applied a method of bioencapsulation using newly hatched brine shrimp (Artemia franciscana) nauplii to study the toxicokinetics of five chlorinated and brominated halogenated acetic acids (HAAs), which are drinking water disinfection by-products. These results are compared to those obtained in a previous study using a polybrominated diphenyl ether (PBDE-47), a highly lipophilic chemical. The HAAs and PBDE-47 were bioencapsulated using freshly hatched A. franciscana nauplii after incubation in concentrated solutions of the study chemicals for 18 h. Aliquots of the brine shrimp were quantitatively removed for chemical analysis and fed to individual fish that were able to consume 400-500 nauplii in less than 5 min. At select times after feeding, fish were euthanized and the HAA or PBDE-47 content determined. The absorption of HAAs was quantitatively similar to previous studies in rodents: rapid absorption with peak body levels occurring within 1-2 h, then rapidly declining with elimination half-life of 0.3-3 h depending on HAA. PBDE-47 was more slowly absorbed with peak levels occurring by 18 h and very slowly eliminated with an elimination half-life of 281 h. PMID:17188578

  6. Quantitative oral dosing of water soluble and lipophilic contaminants in the Japanese medaka (Oryzias latipes)

    SciTech Connect

    Schultz, Irv; Reed, Stacey M.; Pratt, Amanda V.; Skillman, Ann D.

    2007-02-01

    Quantitative oral dosing in fish can be challenging, particularly with water soluble contaminants, which can leach into the aquarium water prior to ingestion. We applied a method of bioencapsulation using newly hatched brine shrimp (Artemia franciscana) nauplii to study the toxicokinetics of five chlorinated and brominated halogenated acetic acids (HAAs), which are drinking water disinfection by-products. These results are compared to those obtained in a previous study using a polybrominated diphenyl ether (PBDE-47), a highly lipophilic chemical. The HAAs and PBDE-47 were bioencapsulated using freshly hatched A. franciscana nauplii after incubation in concentrated solutions of the study chemicals for 18 h. Aliquots of the brine shrimp were quantitatively removed for chemical analysis and fed to individual fish that were able to consume 400–500 nauplii in less than 5min. At select times after feeding, fish were euthanized and the HAA or PBDE-47 content determined. The absorption of HAAs was quantitatively similar to previous studies in rodents: rapid absorptionwith peak body levels occurringwithin 1–2 h, then rapidly declining with elimination half-life of 0.3–3 h depending on HAA. PBDE-47 was more slowly absorbed with peak levels occurring by 18 h and very slowly eliminated with an elimination half-life of 281 h.

  7. Evaluation of 2-week repeated oral dose toxicity of 100 nm zinc oxide nanoparticles in rats

    PubMed Central

    Ko, Je-Won; Hong, Eun-Taek; Lee, In-Chul; Park, Sung-Hyeuk; Park, Jong-Il; Seong, Nak-Won; Hong, Jeong-Sup; Yun, Hyo-In

    2015-01-01

    The aim of this study was to verify subacute oral dose toxicity of positively charged 100 nm zinc oxide (ZnOAE100[+]) nanoparticles (NPs) in Sprague-Dawley rats. ZnOAE100[+] NPs were administered to rats of each sex by gavage at 0, 500, 1,000, and 2,000 mg/kg/day for 14 days. During the study period, clinical signs, mortality, body weight, food consumption, hematology, serum biochemistry, gross pathology, organ weight, and histopathology were examined. Increased mortality and clinical signs, decreased body weight, feed consumption, hemoglobin (HB), hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), platelet (PT), and lymphocyte (LYM) and increased white blood cells (WBCs), neutrophils (NEUs), alkaline phosphatase (ALP), and histopathological alterations in the spleen, stomach, and pancreas were observed at 2,000 mg/kg/day. Increased clinical signs, decreased body weight, feed consumption, HB, HCT, MCV, MCH, MCHC, and LYM and increased WBCs, NEUs, ALP, and histopathological alterations in the spleen, stomach, and pancreas were seen at 1,000 mg/kg/day. Increased clinical signs, decreased MCV and MCH and increased histopathological alterations in the stomach and pancreas were found at 500 mg/kg/day. These results suggest that the target organs were the spleen, stomach, and pancreas in rats. The no-observed-adverse-effect level was <500 mg/kg for both sexes. PMID:26472967

  8. A 13-week repeated-dose oral toxicity and bioaccumulation of aluminum oxide nanoparticles in mice.

    PubMed

    Park, Eun-Jung; Sim, Jaehoon; Kim, Younghun; Han, Beom Seok; Yoon, Cheolho; Lee, Somin; Cho, Myung-Haing; Lee, Byoung-Seok; Kim, Jae-Ho

    2015-03-01

    Because of an increase in the commercial applications of manufactured nanoparticles, the issue of potential adverse health effects of nanoparticles following intended or unintended exposure is rapidly gaining attention. In this study, we evaluated the toxicity of aluminum oxide nanoparticles (AlNPs, rod-type, 1.5, 3, and 6 mg/kg) after oral administration to mice for 13 weeks. Compared with the control group, the consumption of diet and drinking water and body weight gain decreased in the group treated with AlNPs. The group treated with 6 mg/kg AlNPs also showed a marked elevation in the count of white blood cells that associated with a significant decrease and increase to the proportion of eosinophils and lymphocytes, respectively. In addition, the secretion of IL-6 and monocyte chemotactic protein-1 increased in a dose-dependent manner in the treated groups. Furthermore, AlNPs showed the highest accumulation in the liver and kidneys compared with the control group, increased the lactate dehydrogenase level in the blood, and induced the development of a pathological lesion in the liver and kidneys. Taken together, we suggest that the target organs of rod-type AlNPs may be the liver, kidneys and the immune system, and the not-observed adverse effect level may be lower than 6 mg/kg.

  9. The effect of high dose oral manganese exposure on copper, iron and zinc levels in rats.

    PubMed

    Mercadante, Courtney J; Herrera, Carolina; Pettiglio, Michael A; Foster, Melanie L; Johnson, Laura C; Dorman, David C; Bartnikas, Thomas B

    2016-06-01

    Manganese is an essential dietary nutrient and trace element with important roles in mammalian development, metabolism, and antioxidant defense. In healthy individuals, gastrointestinal absorption and hepatobiliary excretion are tightly regulated to maintain systemic manganese concentrations at physiologic levels. Interactions of manganese with other essential metals following high dose ingestion are incompletely understood. We previously reported that gavage manganese exposure in rats resulted in higher tissue manganese concentrations when compared with equivalent dietary or drinking water manganese exposures. In this study, we performed follow-up evaluations to determine whether oral manganese exposure perturbs iron, copper, or zinc tissue concentrations. Rats were exposed to a control diet with 10 ppm manganese or dietary, drinking water, or gavage exposure to approximately 11.1 mg manganese/kg body weight/day for 7 or 61 exposure days. While manganese exposure affected levels of all metals, particularly in the frontal cortex and liver, copper levels were most prominently affected. This result suggests an under-appreciated effect of manganese exposure on copper homeostasis which may contribute to our understanding of the pathophysiology of manganese toxicity. PMID:26988220

  10. Comparison of distribution and toxicity following repeated oral dosing of different vanadium oxide nanoparticles in mice.

    PubMed

    Park, Eun-Jung; Lee, Gwang-Hee; Yoon, Cheolho; Kim, Dong-Wan

    2016-10-01

    Vanadium is an important ultra-trace element derived from fuel product combustion. With the development of nanotechnology, vanadium oxide nanoparticles (VO NPs) have been considered for application in various fields, thus the possibility of release into the environment and human exposure is also increasing. Considering that verification of bioaccumulation and relevant biological responses are essential for safe application of products, in this study, we aimed to identify the physicochemical properties that determine their health effects by comparing the biological effects and tissue distribution of different types of VO NPs in mice. For this, we prepared five types of VO NPs, commercial (C)-VO2 and -V2O5 NPs and synthetic (S)-VO2, -V2O3, and -V2O5 NPs. While the hydrodynamic diameter of the two types of C-VO NPs was irregular and impossible to measure, those of the three types of S-VO NPs was in the range of 125-170nm. The S- and C-V2O5 NPs showed higher dissolution rates compared to other VO NPs. We orally dosed the five types of VO NPs (70 and 210μg/mouse, approximately 2 and 6mg/kg) to mice for 28 days and compared their biodistribution and toxic effects. We found that S-V2O5 and S-V2O3 NPs more accumulated in tissues compared to other three types of VO NPs, and the accumulated level was in order of heart>liver>kidney>spleen. Additionally, tissue levels of redox reaction-related elements and electrolytes (Na(+), K(+), and Ca(2+)) were most clearly altered in the heart of treated mice. Notably, all S- and C-VO NPs decreased the number of WBCs at the higher dose, while total protein and albumin levels were reduced at the higher dose of S-V2O5 and S-V2O3 NPs. Taken together, we conclude that the biodistribution and toxic effects of VO NPs depend on their dissolution rates and size (surface area). Additionally, we suggest that further studies are needed to clarify effects of VO NPs on functions of the heart and the immune system.

  11. High dose weekly oral prednisone improves strength in boys with Duchenne muscular dystrophy.

    PubMed

    Connolly, Anne M; Schierbecker, Jeanine; Renna, Renee; Florence, Julaine

    2002-12-01

    Daily prednisone improves strength in boys with Duchenne muscular dystrophy, but side effects are almost universal. We used a different dosing regimen of prednisone to determine if benefit to boys with Duchenne muscular dystrophy might be maintained with fewer side effects. Twice weekly oral prednisone was given each Friday and Saturday (5mg/kg/dose). This total dose is twice as high as the daily low dosage prednisone regimen (0.75 mg/kg/day). Twenty boys (8.0+/-1.2 years) were treated. Historical control groups included 18 untreated boys (6.1+/-1.6 years) and four boys (7.3+/-0.6 years) treated with daily prednisone. Strength (using a hand-held manometer and grip meter) and timed functional testing were measured. There was an improvement in upper extremity strength for 95% of boys (n=20) at 6 months using quantitative strength testing. Improvement in lower extremity strength occurred in all boys with antigravity quadriceps strength (17/17). The improvement (P=0.001 for proximal upper extremities; P=0.002 for grip; and P<0.0001 for proximal lower extremities) was significant compared to untreated boys. Sixteen boys were treated continuously for more than 12 months (22+/-1.5 months). Of these, 15 remained significantly stronger than prior to treatment and 8/16 showed additional gains in strength after six months of treatment. Six boys were on the weekly prednisolone 2 years or longer without interruption. All six had upper and lower extremity strength at follow-up that was as good or better than at baseline. Functional testing improved in boys less than 8 years without contractures. Three boys without antigravity quadriceps strength at the start of treatment lost the ability to walk unassisted within 6 months. Eight other boys lost the ability to ambulate unassisted between 12 and 24 months of treatment. In each, progressive contractures developed. Linear growth was maintained in all boys on weekly treatment. Obesity rates did not differ from untreated boys. Twice

  12. Efficacy and safety of extended dosing schedules of CC-486 (oral azacitidine) in patients with lower-risk myelodysplastic syndromes.

    PubMed

    Garcia-Manero, G; Gore, S D; Kambhampati, S; Scott, B; Tefferi, A; Cogle, C R; Edenfield, W J; Hetzer, J; Kumar, K; Laille, E; Shi, T; MacBeth, K J; Skikne, B

    2016-04-01

    CC-486, the oral formulation of azacitidine (AZA), is an epigenetic modifier and DNA methyltransferase inhibitor in clinical development for treatment of hematologic malignancies. CC-486 administered for 7 days per 28-day treatment cycle was evaluated in a phase 1 dose-finding study. AZA has a short plasma half-life and DNA incorporation is S-phase-restricted; extending CC-486 exposure may increase the number of AZA-affected diseased target cells and maximize therapeutic effects. Patients with lower-risk myelodysplastic syndromes (MDS) received 300 mg CC-486 once daily for 14 days (n=28) or 21 days (n=27) of repeated 28-day cycles. Median patient age was 72 years (range 31-87) and 75% of patients had International Prognostic Scoring System Intermediate-1 risk MDS. Median number of CC-486 treatment cycles was 7 (range 2-24) for the 14-day dosing schedule and 6 (1-24) for the 21-day schedule. Overall response (complete or partial remission, red blood cell (RBC) or platelet transfusion independence (TI), or hematologic improvement) (International Working Group 2006) was attained by 36% of patients receiving 14-day dosing and 41% receiving 21-day dosing. RBC TI rates were similar with both dosing schedules (31% and 38%, respectively). CC-486 was generally well-tolerated. Extended dosing schedules of oral CC-486 may provide effective long-term treatment for patients with lower-risk MDS. PMID:26442612

  13. Efficacy and safety of extended dosing schedules of CC-486 (oral azacitidine) in patients with lower-risk myelodysplastic syndromes.

    PubMed

    Garcia-Manero, G; Gore, S D; Kambhampati, S; Scott, B; Tefferi, A; Cogle, C R; Edenfield, W J; Hetzer, J; Kumar, K; Laille, E; Shi, T; MacBeth, K J; Skikne, B

    2016-04-01

    CC-486, the oral formulation of azacitidine (AZA), is an epigenetic modifier and DNA methyltransferase inhibitor in clinical development for treatment of hematologic malignancies. CC-486 administered for 7 days per 28-day treatment cycle was evaluated in a phase 1 dose-finding study. AZA has a short plasma half-life and DNA incorporation is S-phase-restricted; extending CC-486 exposure may increase the number of AZA-affected diseased target cells and maximize therapeutic effects. Patients with lower-risk myelodysplastic syndromes (MDS) received 300 mg CC-486 once daily for 14 days (n=28) or 21 days (n=27) of repeated 28-day cycles. Median patient age was 72 years (range 31-87) and 75% of patients had International Prognostic Scoring System Intermediate-1 risk MDS. Median number of CC-486 treatment cycles was 7 (range 2-24) for the 14-day dosing schedule and 6 (1-24) for the 21-day schedule. Overall response (complete or partial remission, red blood cell (RBC) or platelet transfusion independence (TI), or hematologic improvement) (International Working Group 2006) was attained by 36% of patients receiving 14-day dosing and 41% receiving 21-day dosing. RBC TI rates were similar with both dosing schedules (31% and 38%, respectively). CC-486 was generally well-tolerated. Extended dosing schedules of oral CC-486 may provide effective long-term treatment for patients with lower-risk MDS.

  14. Efficacy and safety of extended dosing schedules of CC-486 (oral azacitidine) in patients with lower-risk myelodysplastic syndromes

    PubMed Central

    Garcia-Manero, G; Gore, S D; Kambhampati, S; Scott, B; Tefferi, A; Cogle, C R; Edenfield, W J; Hetzer, J; Kumar, K; Laille, E; Shi, T; MacBeth, K J; Skikne, B

    2016-01-01

    CC-486, the oral formulation of azacitidine (AZA), is an epigenetic modifier and DNA methyltransferase inhibitor in clinical development for treatment of hematologic malignancies. CC-486 administered for 7 days per 28-day treatment cycle was evaluated in a phase 1 dose-finding study. AZA has a short plasma half-life and DNA incorporation is S-phase-restricted; extending CC-486 exposure may increase the number of AZA-affected diseased target cells and maximize therapeutic effects. Patients with lower-risk myelodysplastic syndromes (MDS) received 300 mg CC-486 once daily for 14 days (n=28) or 21 days (n=27) of repeated 28-day cycles. Median patient age was 72 years (range 31–87) and 75% of patients had International Prognostic Scoring System Intermediate-1 risk MDS. Median number of CC-486 treatment cycles was 7 (range 2–24) for the 14-day dosing schedule and 6 (1–24) for the 21-day schedule. Overall response (complete or partial remission, red blood cell (RBC) or platelet transfusion independence (TI), or hematologic improvement) (International Working Group 2006) was attained by 36% of patients receiving 14-day dosing and 41% receiving 21-day dosing. RBC TI rates were similar with both dosing schedules (31% and 38%, respectively). CC-486 was generally well-tolerated. Extended dosing schedules of oral CC-486 may provide effective long-term treatment for patients with lower-risk MDS. PMID:26442612

  15. Pharmacokinetics of daikenchuto, a traditional Japanese medicine (kampo) after single oral administration to healthy Japanese volunteers.

    PubMed

    Munekage, Masaya; Kitagawa, Hiroyuki; Ichikawa, Kengo; Watanabe, Junko; Aoki, Katsuyuki; Kono, Toru; Hanazaki, Kazuhiro

    2011-10-01

    The pharmacokinetics of daikenchuto (TJ-100), a pharmaceutical-grade traditional Japanese medicine, were investigated in healthy Japanese volunteers after a single oral administration of 2.5-, 5-, and 10-g doses. Six ingredients [hydroxy-α-sanshool (HAS), hydroxy-β-sanshool (HBS), [6]-shogaol (6S), [10]-shogaol (10S), ginsenoside Rb₁(GRB1), and ginsenoside Rg₁(GRG1)] of TJ-100 were determined by using liquid chromatography-tandem mass spectrometry. The results indicated that HAS, an ingredient derived from Zanthoxylum piperitum fruit, exhibited the highest plasma concentration among the six ingredients investigated. The plasma concentrations of HAS, HBS, 6S, and 10S reached the maximum concentration (approximately 400, 80, 0.14, and 0.6 ng/ml, respectively, after a 5-g administration of TJ-100) within 30 min after administration, and the mean half-life was approximately 2 h. Thus, these compounds were rapidly absorbed and eliminated. The plasma concentration of GRB1 reached the maximum concentration (2 ng/ml after a 5-g administration of TJ-100) at approximately 4 h after administration and the half-life of GRB1 was approximately 40 h. The plasma concentration of GRG1 was extremely low (<0.023 ng/ml). The pharmacokinetics of HAS, HBS, 6S, and 10S, were linear within the range of 2.5 to 10 g/day of TJ-100. On the other hand, the kinetics of GRB1 and GRG1 were not proportional to dosage, and plateauing was observed.

  16. High-dose oral ziprasidone versus conventional dosing in schizophrenia patients with residual symptoms: the ZEBRAS study.

    PubMed

    Goff, Donald C; McEvoy, Joseph P; Citrome, Leslie; Mech, Arnold W; Bustillo, Juan R; Gil, Roberto; Buckley, Peter; Manschreck, Theo C; Achtyes, Eric D; Macklin, Eric A

    2013-08-01

    Uncontrolled studies have suggested that increasing the dose of ziprasidone above the standard maximum daily dose of 160 mg may be more effective for some patients with schizophrenia. To test this hypothesis, we conducted an 8-week, placebo-controlled, fixed-dose escalation trial comparing ziprasidone 160 versus 320 mg/d in individuals with schizophrenia or schizoaffective disorder who remained symptomatic despite treatment with ziprasidone 160 mg/d for at least 3 weeks. Of 75 randomized patients, 42 completed the study. Serum ziprasidone concentrations increased significantly in the high-dose group compared with the standard-dose group at week 4 but did not differ between groups at week 8. Both treatment groups exhibited significant symptomatic improvement. Response did not differ between treatment groups; however, in the high-dose group, higher ziprasidone serum concentrations were associated with better response at a trend level. Higher ziprasidone concentrations were also associated with reductions in diastolic blood pressure and, at a trend level, with more prominent negative symptoms and greater QTc prolongation. In summary, increasing the ziprasidone dose to 320 mg/d did not produce a sustained elevation in serum concentrations or symptomatic improvement compared with a standard ziprasidone dose of 160 mg/d.

  17. Single-dose intrapulmonary pharmacokinetics of azithromycin, clarithromycin, ciprofloxacin, and cefuroxime in volunteer subjects.

    PubMed

    Conte, J E; Golden, J; Duncan, S; McKenna, E; Lin, E; Zurlinden, E

    1996-07-01

    The intrapulmonary pharmacokinetics of azithromycin, clarithromycin, ciprofloxacin, and cefuroxime were studied in 68 volunteers who received single, oral doses of azithromycin (0.5 g), clarithormycin (0.5 g), ciprofloxacin (0.5 g), or cefuroxime (0.5 g). In subgroups of four subjects each, the subjects underwent bronchoscopy and bronchoalveolar lavage at timed intervals following drug administration. Drug concentrations, including those of 14-hydroxyclarithromycin (14H), were determined in serum, bronchoalveolar lavage fluid, and alveolar cells (ACs) by high-pressure liquid chromatography. Concentrations in epithelial lining fluid (ELF) were calculated by the urea diffusion method. The maximum observed concentrations (mean +/- standard deviation) of azithromycin, clarithromycin, 14H, ciprofloxacin, and cefuroxime in serum were 0.13 +/- 0.07, 1.0 +/- 0.6, 0.60 +/- 0.41, 0.95 +/- 0.32, and 1.1 +/- 0.3 microgram/ml, respectively (all at 6 h). None of the antibiotics except clarithromycin (39.6 +/- 41.1 micrograms/ml) was detectable in ELF at the 6-h bronchoscopy. The movement into and persistence in cells was different for azithromycin and clarithromycin. In ACs azithromycin was not detectable at 6 h, reached its highest concentration at 120 h, and exhibited the greatest area under the curve (7,403 micrograms.hr ml-1). The peak concentration of clarithromycin (181 +/- 94.1 micrograms/ml) was greater and occurred earlier (6 h), but the area under the curve (2,006 micrograms.hr ml-1) was less than that observed for azithromycin. 14H was detectable in ACs at 6 h (40.3 +/- 5.2 micrograms/ml) and 12 h (32.8 +/- 57.2 micrograms/ml). The peak concentration of ciprofloxacin occurred at 6 h (4.3 +/- 5.2 micrograms/ml), and the area under the curve was 35.0 micrograms.hr ml-1. The data indicate that after the administration of a single dose, azithromycin, clarithromycin, and ciprofloxacin penetrated into ACs in therapeutic concentrations and that only clarithromycin was

  18. Single or 2-Dose Micafungin Regimen for Treatment of Invasive Candidiasis: Therapia Sterilisans Magna!

    PubMed

    Gumbo, Tawanda

    2015-12-01

    The time the earth takes to rotate its axis (the day) has dictated how often pharmaceutical compounds are dosed. The scientific link between the 2 events is materia medica arcana. As an example, in the treatment of invasive candidiasis, antifungal therapy with intravenous micafungin is dosed daily. A literature review revealed population pharmacokinetic analyses, in vivo pharmacokinetics/pharmacodynamics studies, and maximum-tolerated-dose studies of micafungin that examined optimal micafungin dosing strategies. The half-life of micafungin in patient blood was 14 hours in several studies, but was even longer in different organs, so that the concentration will persist above minimum inhibitory concentrations of Candida species for several days. Studies in mice and rabbits with persistent neutropenia and disseminated candidiasis, otherwise fatal, demonstrated that a single large dose of micafungin could clear disseminated candidiasis, even though the micafungin half-life in such animals is shorter than in humans. Human pharmacokinetics/pharmacodynamics studies confirmed this link between micafungin efficacy and the ratio of the area under the concentration-time curve, and the optimal exposures initially identified in neutropenic animals. Maximum tolerated dose studies have demonstrated safety of 900 mg administered daily for several weeks, whereas case reports demonstrate efficacy and safety of single 1400-mg doses. Thus, a single dose of micafungin, or 2 such doses within a few days of each other, is not only logical, but might even lead to faster clearance of Candida.

  19. Single or 2-Dose Micafungin Regimen for Treatment of Invasive Candidiasis: Therapia Sterilisans Magna!

    PubMed

    Gumbo, Tawanda

    2015-12-01

    The time the earth takes to rotate its axis (the day) has dictated how often pharmaceutical compounds are dosed. The scientific link between the 2 events is materia medica arcana. As an example, in the treatment of invasive candidiasis, antifungal therapy with intravenous micafungin is dosed daily. A literature review revealed population pharmacokinetic analyses, in vivo pharmacokinetics/pharmacodynamics studies, and maximum-tolerated-dose studies of micafungin that examined optimal micafungin dosing strategies. The half-life of micafungin in patient blood was 14 hours in several studies, but was even longer in different organs, so that the concentration will persist above minimum inhibitory concentrations of Candida species for several days. Studies in mice and rabbits with persistent neutropenia and disseminated candidiasis, otherwise fatal, demonstrated that a single large dose of micafungin could clear disseminated candidiasis, even though the micafungin half-life in such animals is shorter than in humans. Human pharmacokinetics/pharmacodynamics studies confirmed this link between micafungin efficacy and the ratio of the area under the concentration-time curve, and the optimal exposures initially identified in neutropenic animals. Maximum tolerated dose studies have demonstrated safety of 900 mg administered daily for several weeks, whereas case reports demonstrate efficacy and safety of single 1400-mg doses. Thus, a single dose of micafungin, or 2 such doses within a few days of each other, is not only logical, but might even lead to faster clearance of Candida. PMID:26567282

  20. Effects of multiple oral dosing on IgE synthesis in mice: oral sensitization by albumin extracts from seeds of Jack fruit (Artocarpus integrifolia) containing lectins.

    PubMed Central

    Restum-Miguel, N; Prouvost-Danon, A

    1985-01-01

    The IgE antibody response was studied in DBA/2 mice; the mice were pretreated orally with albumin extracts from seeds of Jack fruit (Jackalbumin) and subsequently immunized subcutaneously with Jackalbumin mixed with ovalbumin (OA) and a synthetic adjuvant, muramyl dipeptide (MDP). The allergenicity of Jackalbumin was evaluated by its capacity to induce a specific IgE response which was measured by passive cutaneous anaphylaxis (PCA) and by degranulation of washed peritoneal mast cells following antigen challenge (Jackalbumin or OA). Antibody against the crude extracts and anti-lectin (FIISP) IgE responses were also tested by PCA. After being fed eight doses of 1 mg Jackalbumin, DBA/2 mice became immunized: i.e. specific IgE antibody responses were observed and the peritoneal mast cells became sensitized. An increase in IgE response was verified in mice that were pre-fed and subsequently immunized. The results indicated that: the albumin extracts from Jack seeds, containing lectins, can be allergenic by the oral route; multiple oral doses with these extracts can induce an enhancement of the IgE response on subsequent subcutaneous immunization; antigenically, Jackalbumin does not seem to cross-react with OA; the lectins contained in the albumin fraction from Artocarpus seeds were also shown to be allergenic; the IgE titres showed an inverse correlation to the degree of purification of the lectin used for PCA challenge. PMID:3972438

  1. Effects of multiple oral dosing on IgE synthesis in mice: oral sensitization by albumin extracts from seeds of Jack fruit (Artocarpus integrifolia) containing lectins.

    PubMed

    Restum-Miguel, N; Prouvost-Danon, A

    1985-03-01

    The IgE antibody response was studied in DBA/2 mice; the mice were pretreated orally with albumin extracts from seeds of Jack fruit (Jackalbumin) and subsequently immunized subcutaneously with Jackalbumin mixed with ovalbumin (OA) and a synthetic adjuvant, muramyl dipeptide (MDP). The allergenicity of Jackalbumin was evaluated by its capacity to induce a specific IgE response which was measured by passive cutaneous anaphylaxis (PCA) and by degranulation of washed peritoneal mast cells following antigen challenge (Jackalbumin or OA). Antibody against the crude extracts and anti-lectin (FIISP) IgE responses were also tested by PCA. After being fed eight doses of 1 mg Jackalbumin, DBA/2 mice became immunized: i.e. specific IgE antibody responses were observed and the peritoneal mast cells became sensitized. An increase in IgE response was verified in mice that were pre-fed and subsequently immunized. The results indicated that: the albumin extracts from Jack seeds, containing lectins, can be allergenic by the oral route; multiple oral doses with these extracts can induce an enhancement of the IgE response on subsequent subcutaneous immunization; antigenically, Jackalbumin does not seem to cross-react with OA; the lectins contained in the albumin fraction from Artocarpus seeds were also shown to be allergenic; the IgE titres showed an inverse correlation to the degree of purification of the lectin used for PCA challenge.

  2. Pharmacokinetics of single ascending doses of the P-glycoprotein inhibitor tariquidar in healthy subjects

    PubMed Central

    Bauer, M.; Zeitlinger, M.; Todorut, D.; Böhmdorfer, M.; Müller, M.; Langer, O.; Jäger, W.

    2013-01-01

    We assessed the pharmacokinetics (PK), tolerability and safety of tariquidar (TQD), a P-glycoprotein (Pgp) inhibitor, after i.v. administration of single ascending doses. Employed doses were up to 4-fold higher than in previous clinical trials in cancer patients and are capable to inhibit Pgp at the blood-brain barrier (BBB). 15 male healthy volunteers were randomised to receive single i.v. doses of TQD at 4, 6 or 8 mg/kg body weight and underwent blood sampling over 24 h. TQD concentrations were determined in plasma samples with high-performance liquid chromatography-mass spectrometry. No dose limiting toxicities of TQD were observed. Area under the plasma concentration-time curve from start until 24 h after end of infusion (AUC0-n) was positively correlated with administered TQD dose (r=0.8981, p<0.0001). Moreover, we found a positive correlation for volume of distribution at steady state Vss (r=0.7129, p=0.0004) with TQD dose. Dose dependency of Vss points to non-linear PK of TQD, which was in all likelihood caused by transporter saturation at high TQD doses. Acceptable safety and tolerability and dose-linear increases in plasma exposure support future use of TQD at doses up to 8 mg/kg to inhibit Pgp at the human BBB. PMID:23146816

  3. Disposition of Lead (Pb) in Saliva and Blood of Sprague-Dawley Rats Following a Single or Repeated Oral Exposure to Pb-Acetate

    SciTech Connect

    Timchalk, Chuck; Lin, Yuehe; Weitz, Karl K.; Wu, Hong; Gies, Richard A.; Moore, Dean A.; Yantasee, Wassana

    2006-05-01

    Biological monitoring for lead (Pb) is usually based upon a determination of blood Pb concentration; however, saliva has been suggested as a non-invasive biological matrix for assessing exposure. To further evaluate the potential utility of saliva for biomonitoring, the disposition of Pb was evaluated in whole blood (WB), red blood cells (RBC), plasma, parotid gland, bone, and saliva following either a single oral dose of 100 mg Pb-acetate/kg body weight in rats or {approx}1-week after 5 sequential daily oral gavage doses of 1, 10, or 100 mg Pb-acetate/kg/day. Saliva volume, pH, total saliva protein, and ?-amylase activity were also determined. At specified times post-dosing groups of animals were anethetized and administered pilocarpine to induce salivation. Saliva was collected, the animals were humanely sacrificed, and tissue samples were likewise collected, weighed, and processed for Pb analysis. Following a single dose exposure to PB-acetate, Pb was detectable in all samples by 30 min post-dosing. For both the single and repeated dose treatments the concentration of Pb was highest in WB and RBC relative to plasma and saliva. However, the Pb rapidly redistributed (within 5-days post-treatment) from the blood into the bone compartment based on the substantial decrease in WB and RBC Pb concentration, and the concurrent increase in bone Pb following repeated exposure at all dose levels. Although there is clear variability in the observed Pb concentrations in plasma and saliva, there was a reasonable correlation (r2=0.922) between the average Pb concentrations in these biological matrices which was consistent with previous observations. The single oral dose of Pb-acetate resulted in a decrease in salivary pH which recovered by 24 hr post-dosing and a decrease in ?-amylase enzyme activity which did recover within 5-days of ceasing exposure. It is currently unclear what impact these slight functional changes may or may not have on Pb salivary clearance rates. These

  4. Effects of repeated oral doses of dexnorfenfluramine on 5-HT levels and 5-HT uptake sites in rat brain.

    PubMed

    Gobbi, M; Bergami, A; Caltavuturo, C; Valle, F D; Mennini, T; Caccia, S

    1996-11-15

    The effects of oral dexnorfenfluramine (DNF; 1-4 mg/kg, twice daily for 4 days), the active metabolite of dexfenfluramine, were examined on rat regional brain indole contents and [3H]citalopram binding. Two hours after the last dose, serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) were dose-dependently lowered at doses above 1.5 mg/kg, with slight regional differences. Cortical 5-HT uptake sites were reduced only at the highest dose. Above 2 mg/kg DNF also caused a more lasting reduction (4 weeks) of regional indoles and cortical 5-HT uptake sites. At this longer time while the decrease in hippocampal 5-HT levels and cortical 5-HT uptake sites remained essentially constant, cortical and striatal 5-HT levels were lowered less than at 2 h, suggesting a return toward control values.

  5. Oral dosing with papaya latex is an effective anthelmintic treatment for sheep infected with Haemonchus contortus

    PubMed Central

    2011-01-01

    Background The cysteine proteinases in papaya latex have been shown to have potent anthelmintic properties in monogastric hosts such as rodents, pigs and humans, but this has not been demonstrated in ruminants. Methods In two experiments, sheep were infected concurrently with 5,000 infective larvae of Haemonchus contortus and 10,000 infective larvae of Trichostrongylus colubriformis and were then treated with the supernatant from a suspension of papaya latex from day 28 to day 32 post-infection. Faecal egg counts were monitored from a week before treatment until the end of the experiment and worm burdens were assessed on day 35 post-infection. Results We found that the soluble fraction of papaya latex had a potent in vivo effect on the abomasal nematode H. contortus, but not on the small intestinal nematode T. colubriformis. This effect was dose-dependent and at tolerated levels of gavage with papaya latex (117 μmol of active papaya latex supernatant for 4 days), the H. contortus worm burdens were reduced by 98%. Repeated treatment, daily for 4 days, was more effective than a single dose, but efficacy was not enhanced by concurrent treatment with the antacid cimetidine. Conclusions Our results provide support for the idea that cysteine proteinases derived from papaya latex may be developed into novel anthelmintics for the treatment of lumenal stages of gastro-intestinal nematode infections in sheep, particularly those parasitizing the abomasum. PMID:21406090

  6. Effect of low-dose (single-dose) magnesium sulfate on postoperative analgesia in hysterectomy patients receiving balanced general anesthesia.

    PubMed

    Taheri, Arman; Haryalchi, Katayoun; Mansour Ghanaie, Mandana; Habibi Arejan, Neda

    2015-01-01

    Background and Aim. Aparallel, randomized, double blinded, placebo-controlled trial study was designed to assess the efficacy of single low dose of intravenous magnesium sulfate on post-total abdominal hysterectomy (TAH) pain relief under balanced general anesthesia. Subject and Methods. Forty women undergoing TAH surgery were assigned to two magnesium sulfate (N = 20) and normal saline (N = 20) groups randomly. The magnesium group received magnesium sulfate 50 mg·kg(-1) in 100 mL of normal saline solution i.v as single-dose, just 15 minutes before induction of anesthesia whereas patients in control group received 100 mL of 0.9% sodium chloride solution at the same time. The same balanced general anesthesia was induced for two groups. Pethidine consumption was recorded over 24 hours precisely as postoperative analgesic. Pain score was evaluated with Numeric Rating Scale (NRS) at 0, 6, 12, and 24 hours after the surgeries. Results. Postoperative pain score was lower in magnesium group at 6, 12, and 24 hours after the operations significantly (P < 0.05). Pethidine requirement was significantly lower in magnesium group throughout 24 hours after the surgeries (P = 0.0001). Conclusion. Single dose of magnesium sulfate during balanced general anesthesia could be considered as effective and safe method to reduce postoperative pain and opioid consumption after TAH.

  7. A New Orally Active, Aminothiol Radioprotector-Free of Nausea and Hypotension Side Effects at Its Highest Radioprotective Doses

    SciTech Connect

    Soref, Cheryl M.; Hacker, Timothy A.; Fahl, William E.

    2012-04-01

    Purpose: A new aminothiol, PrC-210, was tested for orally conferred radioprotection (rats, mice; 9.0 Gy whole-body, which was otherwise lethal to 100% of the animals) and presence of the debilitating side effects (nausea/vomiting, hypotension/fainting) that restrict use of the current aminothiol, amifostine (Ethyol, WR-2721). Methods and Materials: PrC-210 in water was administered to rats and mice at times before irradiation, and percent-survival was recorded for 60 days. Subcutaneous (SC) amifostine (positive control) or SC PrC-210 was administered to ferrets (Mustela putorius furo) and retching/emesis responses were recorded. Intraperitoneal amifostine (positive control) or PrC-210 was administered to arterial cannulated rats to score drug-induced hypotension. Results: Oral PrC-210 conferred 100% survival in rat and mouse models against an otherwise 100% lethal whole-body radiation dose (9.0 Gy). Oral PrC-210, administered by gavage 30-90 min before irradiation, conferred a broad window of radioprotection. The comparison of PrC-210 and amifostine side effects was striking because there was no retching or emesis in 10 ferrets treated with PrC-210 and no induced hypotension in arterial cannulated rats treated with PrC-210. The tested PrC-210 doses were the ferret and rat equivalent doses of the 0.5 maximum tolerated dose (MTD) PrC-210 dose in mice. The human equivalent of this mouse 0.5 MTD PrC-210 dose would likely be the highest PrC-210 dose used in humans. By comparison, the mouse 0.5 MTD amifostine dose, 400 {mu}g/g body weight (equivalent to the human amifostine dose of 910 mg/m{sup 2}), when tested at equivalent ferret and rat doses in the above models produced 100% retching/vomiting in ferrets and 100% incidence of significant, progressive hypotension in rats. Conclusions: The PrC-210 aminothiol, with no detectable nausea/vomiting or hypotension side effects in these preclinical models, is a logical candidate for human drug development to use in healthy

  8. Dose-response relationship of an environmental mixture of pyrethroids following an acute oral administration in the rat

    EPA Science Inventory

    Dose-response relationship of an environmental mixture of pyrethroids following an acute oral administration in the rat M.F. Hughes1, D.G. Ross1, J.M. Starr1, E.J. Scollon1,2, M.J. Wolansky1,3, K.M. Crofton1, M.J. DeVito1,4 1U.S. EPA, ORD, Research Triangle Park, NC, 2U.S. EPA,...

  9. The protective effects of oral low-dose quercetin on diabetic nephropathy in hypercholesterolemic mice

    PubMed Central

    Gomes, Isabele B. S.; Porto, Marcella L.; Santos, Maria C. L. F. S.; Campagnaro, Bianca P.; Gava, Agata L.; Meyrelles, Silvana S.; Pereira, Thiago M. C.; Vasquez, Elisardo C.

    2015-01-01

    Aims: Diabetic nephropathy (DN) is one of the most important causes of chronic renal disease, and the incidence of DN is increasing worldwide. Considering our previous report (Gomes et al., 2014) indicating that chronic treatment with oral low-dose quercetin (10 mg/Kg) demonstrated anti-oxidative, anti-apoptotic and renoprotective effects in the C57BL/6J model of DN, we investigated whether this flavonoid could also have beneficial effects in concurrent DN and spontaneous atherosclerosis using the apolipoprotein E-deficient mouse (apoE−/−). Methods: Streptozotocin was used to induce diabetes (100 mg/kg/day, 3 days) in male apoE−/− mice (8 week-old). After 6 weeks, the mice were randomly separated into DQ: diabetic apoE−/− mice treated with quercetin (10 mg/kg/day, 4 weeks, n = 8), DV: diabetic ApoE−/− mice treated with vehicle (n = 8) and ND: non-treated non-diabetic mice (n = 8). Results: Quercetin treatment diminished polyuria (~30%; p < 0.05), glycemia (~25%, p < 0.05), normalized the hypertriglyceridemia. Moreover, this bioflavonoid diminished creatininemia (~30%, p < 0.01) and reduced proteinuria but not to normal levels. We also observed protective effects on the renal structural changes, including normalization of the index of glomerulosclerosis and kidney weight/body weight. Conclusions: Our data revealed that quercetin treatment significantly reduced DN in hypercholesterolemic mice by inducing biochemical changes (decrease in glucose and triglycerides serum levels) and reduction of glomerulosclerosis. Thus, this study highlights the relevance of quercetin as an alternative therapeutic option for DN, including in diabetes associated with dyslipidemia. PMID:26388784

  10. The maximum single dose of resistant maltodextrin that does not cause diarrhea in humans.

    PubMed

    Kishimoto, Yuka; Kanahori, Sumiko; Sakano, Katsuhisa; Ebihara, Shukuko

    2013-01-01

    The objective of the present study was to determine the maximum dose of resistant maltodextrin (Fibersol)-2, a non-viscous water-soluble dietary fiber), that does not induce transitory diarrhea. Ten healthy adult subjects (5 men and 5 women) ingested Fibersol-2 at increasing dose levels of 0.7, 0.8, 0.9, 1.0, and 1.1 g/kg body weight (bw). Each administration was separated from the previous dose by an interval of 1 wk. The highest dose level that did not cause diarrhea in any subject was regarded as the maximum non-effective level for a single dose. The results showed that no subject of either sex experienced diarrhea at dose levels of 0.7, 0.8, 0.9, or 1.0 g/kg bw. At the highest dose level of 1.1 g/kg bw, no female subject experienced diarrhea, whereas 1 male subject developed diarrhea with muddy stools 2 h after ingestion of the test substance. Consequently, the maximum non-effective level for a single dose of the resistant maltodextrin Fibersol-2 is 1.0 g/kg bw for men and >1.1 g/kg bw for women. Gastrointestinal symptoms were gurgling sounds in 4 subjects (7 events) and flatus in 5 subjects (9 events), although no association with dose level was observed. These symptoms were mild and transient and resolved without treatment.

  11. Evaluation of Genotoxicity and 28-day Oral Dose Toxicity on Freeze-dried Powder of Tenebrio molitor Larvae (Yellow Mealworm).

    PubMed

    Han, So-Ri; Yun, Eun-Young; Kim, Ji-Young; Hwang, Jae Sam; Jeong, Eun Ju; Moon, Kyoung-Sik

    2014-06-01

    The larval form of Tenebrio molitor (T. molitor) has been eaten in many countries and provides benefits as a new food source of protein for humans. However, no information exists regarding its safety for humans. The objective of the present study was to evaluate the genotoxicity and repeated dose oral toxicity of the freeze-dried powder of T. molitor larvae. The genotoxic potential was evaluated by a standard battery testing: bacterial reverse mutation test, in vitro chromosome aberration test, and in vivo micronucleus test. To assess the repeated dose toxicity, the powder was administered once daily by oral gavage to Sprague-Dawley (SD) rats at dose levels of 0, 300, 1000 and 3000 mg/kg/day for 28 days. The parameters which were applied to the study were mortality, clinical signs, body and organ weights, food consumption, ophthalmology, urinalysis, hematology, serum chemistry, gross findings and histopathologic examination. The freezedried powder of T. molitor larvae was not mutagenic or clastogenic based on results of in vitro and in vivo genotoxicity assays. Furthermore, no treatment-related changes or findings were observed in any parameters in rats after 28 days oral administration. In conclusion, the freeze-dried powder of T. molitor larvae was considered to be non-genotoxic and the NOAEL (No Observed Adverse Effect Level) was determined to be 3000 mg/kg/day in both sexes of SD rats under our experimental conditions. PMID:25071922

  12. Phase I, Open-Label, Single-Dose Study To Evaluate the Pharmacokinetics and Safety of Telbivudine in Children and Adolescents with Chronic Hepatitis B

    PubMed Central

    Ke, June; Uy, Grace; Bosheva, Miroslava; Qi, Yin; Praestgaard, Jens

    2013-01-01

    Telbivudine is a nucleoside analogue that has been approved for the treatment of chronic hepatitis B virus (HBV) infection in adults at 600 mg/day. We conducted a phase I, open-label, first-in-pediatrics study to investigate the safety and pharmacokinetics of a single dose of telbivudine in HBV-infected children and adolescents. Eligible patients were enrolled sequentially from older to younger groups, with evaluation of safety and available pharmacokinetic data after each stratum. Adolescent patients (>12 to 18 years) received a single dose of 600 mg telbivudine as an oral solution, while children aged 2 to 12 years received a single dose of 15 or 25 mg/kg of body weight up to a maximum of 600 mg. Telbivudine was well tolerated; all adverse events were mild, and none occurred in more than one patient. The plasma telbivudine concentration-versus-time profiles in adolescents given 600 mg were similar to the mean profile of healthy adults receiving the same oral dose. Children aged 2 to <6 and 6 to 12 years receiving a single 15-mg/kg dose showed similar plasma exposures. To predict the steady-state exposure, plasma concentration-versus-time profiles for patients aged 2 to 12 years (15 mg/kg) and >12 to 18 years (600 mg) were fitted to a two-compartment 1st-order, microconstant, lag time, 1st-order elimination pharmacokinetic (PK) model. This analysis predicted the following dosages to mimic exposures in healthy adults receiving 600 mg/day: 20 mg/kg/day for children 2 to 12 years and 600 mg/day for adolescents. Studies are ongoing to evaluate the efficacy of the recommended dose in pediatric patients. (This study has been registered at ClinicalTrials.gov under registration no. NCT00907894.) PMID:23774433

  13. Low-dose pharmacokinetics and oral bioavailability of dichloroacetate in naive and GST-zeta-depleted rats.

    PubMed Central

    Saghir, Shakil A; Schultz, Irvin R

    2002-01-01

    We studied the pharmacokinetics of dichloroacetate (DCA) in naive rats and rats depleted of glutathione S-transferase-zeta (GST-zeta), at doses approaching human daily exposure levels. We also compared in vitro metabolism of DCA by rat and human liver cytosol. Jugular vein-cannulated male Fischer-344 rats received graded doses of DCA ranging from 0.05 to 20 mg/kg (intravenously or by gavage), and we collected time-course blood samples from the cannulas. GST-zeta activity was depleted by exposing rats to 0.2 g/L DCA in drinking water for 7 days before initiation of pharmacokinetic studies. Elimination of DCA by naive rats was so rapid that only 1-20 mg/kg intravenous and 5 and 20 mg/kg gavage doses provided plasma concentrations above the method detection limit of 6 ng/mL. GST-zeta depletion slowed DCA elimination from plasma, allowing kinetic analysis of doses as low as 0.05 mg/kg. DCA elimination was strongly dose dependent in the naive rats, with total body clearance declining with increasing dose. In the GST-zeta-depleted rats, the pharmacokinetics became linear at doses less than or equal to 1 mg/kg. Virtually all of the dose was eliminated through metabolic clearance; the rate of urinary elimination was < 1 mL/hr/kg. At higher oral doses (less than or equal to 5 mg/kg in GST-zeta-depleted and 20 mg/kg in naive rats), secondary peaks in the plasma concentration appeared long after the completion of the initial absorption phase. Oral bioavailability of DCA was 0-13% in naive and 14-75% in GST-zeta- depleted rats. Oral bioavailability of DCA in humans through consumption of drinking water was predicted to be very low and < 1%. The use of the GST-zeta-depleted rat as a model for assessing the kinetics of DCA in humans is supported by the similarity in pharmacokinetic parameter estimates and rate of in vitro metabolism of DCA by human and GST-zeta-depleted rat liver cytosol. PMID:12153755

  14. No protection by oral terbutaline against exercise-induced asthma in children: a dose-response study.

    PubMed

    Fuglsang, G; Hertz, B; Holm, E B

    1993-04-01

    We wanted to assess the protective effects on exercise-induced asthma as well as the clinical efficacy and safety of increasing doses of a new sustained-release formulation of terbutaline sulphate, in 17 asthmatic children aged 6-12 yrs (mean 9 yrs). Placebo, 2, 4 and 6 mg terbutaline were given b.i.d. for 14 days, in a randomized, double-blind, cross-over design. At the end of each two week period, an exercise test was performed and plasma terbutaline was measured. Compared with placebo, no significant effect was seen on asthma symptoms monitored at home, or on exercise-induced asthma. The percentage falls in FEV1 after the exercise test were 36, 35, 27 and 28%, after placebo, 4, 8 and 12 mg terbutaline.day-1, respectively. There was no correlation between plasma terbutaline and dose of terbutaline. A small but statistically significant dose-related increase in morning and evening peak expiratory flow (PEF) recordings occurred, but the incidence of side-effects also increased with the dose given. There was a trend towards more side-effects when the high doses were used, and two patients withdrew from the study because of side-effects at this dose. It is concluded that continuous treatment, even with high doses of oral terbutaline, does not offer clinically useful protection against exercise-induced asthma. PMID:8491302

  15. Estimation by a 24-hour study of the daily dose of intra-oral mercury vapor inhaled after release from dental amalgam

    SciTech Connect

    Berglund, A. )

    1990-10-01

    The difficulties associated with estimations of daily doses of inhaled mercury vapor released from dental amalgam are considerable. Existing data are often unreliable, especially if they are based on a single or a small series of samples of intra-oral concentrations of mercury vapor before, during, and after chewing stimulation. In the present paper, the aim was to obtain a more representative estimation of the daily dose of mercury vapor inhaled from amalgam fillings by measurement of amounts of mercury vapor released in the oral cavity during 24 h, under conditions that were as normal as possible. A series of measurements was carried out on each of 15 subjects, with at least nine occlusal surfaces restored with dental amalgam, and on five subjects without any amalgam restorations. The subjects had to follow a standardized schedule for 24 h, whereby they ate, drank, and brushed their teeth at pre-determined time periods. The amount of mercury vapor released per time unit was measured at intervals of 30-45 min by means of a measuring system based on atomic absorption spectrophotometry. None of the subjects was professionally exposed to mercury, and all of their amalgam fillings were more than one year old. Study casts were made for each subject, and the area of the amalgam surfaces was measured. Samples of urine and saliva were analyzed so that values for the mercury concentrations and the rate of release of mercury into saliva could be obtained. The average frequency of fish meals per month was noted.

  16. [Clinical usefulness of high-dose oral nitroglycerin in patients with stable angina pectoris].

    PubMed

    Kośmicki, Marek A; Skorykow-Sapińska, Alina; Sadowski, Zygmunt

    2003-01-01

    The aim of this study was to evaluate clinical efficacy and adverse effects of nitroglycerin 15 mg in slow-release form (N-15) after single ingestion. In randomized, double-blind and placebo (P) controlled with cross-over design study 15 male patients with stable angina received N-15 or P. Antianginal efficacy of the drug was evaluated by analysing the parameters of tolerance of effort and coronary reserve taken from serial exercise stress tests on treadmill performed preceding single oral ingestion, 2 hours and 6 hours after. Simple hemodynamic parameters were also evaluated in the rest and during exercise. N-15 significantly improved in comparison to P: total walking time both after 2 hours by 34.3% (p < 0.01) and 6 hours by 23.1% (p < 0.01); walking time to angina after 2 hours by 34.8% (p < 0.01) and 6 hours by 21.7% (p < 0.05), and walking time to ischemia after 2 hours by 66.1% (p < 0.01) and 6 hours by 39.0% (p < 0.05). N-15 significantly increased the rest heart rate in standing position 2 hours after ingestion by 12.3% (p < 0.01) and decreased rest systolic blood pressure in both positions 2 hours after ingestion: in supine by 12.9% (p < 0.01) and standing by 16.3% (p < 0.01) and after 6 hours: in supine by 9.1% (p < 0.05) and standing by 10.0% (p < 0.05). No postural hypotension in any patient occurred. Diastolic blood pressure was significantly decreased only in standing position 2 hours after N-15 ingestion by 12.3% (p < 0.01) and after 6 hours by 9.1% (p < 0.05). During maximal exercise significant reduction of systolic blood pressure occurred 2 hours after ingestion and significant reduction of diastolic blood pressure occurred both 2 hours and 6 hours after ingestion. Adverse effects after single ingestion of N-15 were the few: the headaches were presented only in 4 patients (27%), and in 53% patients any adverse effect occurred. Nitroglycerin 15 mg in slow-release form is an active coronary drug, effective not less than 6 hours after ingestion, and

  17. Prophylactic Oral Dextrose Gel for Newborn Babies at Risk of Neonatal Hypoglycaemia: A Randomised Controlled Dose-Finding Trial (the Pre-hPOD Study)

    PubMed Central

    Hegarty, Joanne Elizabeth; Harding, Jane Elizabeth; Gamble, Gregory David; Crowther, Caroline Anne; Edlin, Richard; Alsweiler, Jane Marie

    2016-01-01

    Background Neonatal hypoglycaemia is common, affecting up to 15% of newborns, and can cause brain damage. Currently, there are no strategies, beyond early feeding, to prevent neonatal hypoglycaemia. Our aim was to determine a dose of 40% oral dextrose gel that will prevent neonatal hypoglycaemia in newborn babies at risk. Methods and Findings We conducted a randomised, double-blind, placebo-controlled dose-finding trial of buccal dextrose gel to prevent neonatal hypoglycaemia at two hospitals in New Zealand. Babies at risk of hypoglycaemia (infant of a mother with diabetes, late preterm delivery, small or large birthweight, or other risk factors) but without indication for admission to a neonatal intensive care unit (NICU) were randomly allocated either to one of four treatment groups: 40% dextrose at one of two doses (0.5 ml/kg = 200 mg/kg, or 1 ml/kg = 400 mg/kg), either once at 1 h of age or followed by three additional doses of dextrose (0.5 ml/kg before feeds in the first 12 h); or to one of four corresponding placebo groups. Treatments were administered by massaging gel into the buccal mucosa. The primary outcome was hypoglycaemia (<2.6 mM) in the first 48 h. Secondary outcomes included admission to a NICU, admission for hypoglycaemia, and breastfeeding at discharge and at 6 wk. Prespecified potential dose limitations were tolerance of gel, time taken to administer, messiness, and acceptability to parents. From August 2013 to November 2014, 416 babies were randomised. Compared to babies randomised to placebo, the risk of hypoglycaemia was lowest in babies randomised to a single dose of 200 mg/kg dextrose gel (relative risk [RR] 0.68; 95% confidence interval [CI] 0.47–0.99, p = 0.04) but was not significantly different between dose groups (p = 0.21). Compared to multiple doses, single doses of gel were better tolerated, quicker to administer, and less messy, but these limitations were not different between dextrose and placebo gel groups. Babies who received

  18. Toxicodynamic effects of ciclosporin are reflected by metabolite profiles in the urine of healthy individuals after a single dose

    PubMed Central

    Klawitter, Jost; Haschke, Manuel; Kahle, Christine; Dingmann, Colleen; Klawitter, Jelena; Leibfritz, Dieter; Christians, Uwe

    2010-01-01

    AIMS The immunosuppressant ciclosporin is an efficient prophylaxis against transplant organ rejection but its clinical use is limited by its nephrotoxicity. Our previous systematic studies in the rat indicated urine metabolite pattern changes to be sensitive indicators of the negative effects of ciclosporin on the kidney. To translate these results, we conducted an open label, placebo-controlled, crossover study assessing the time-dependent toxicodynamic effects of a single oral ciclosporin dose (5 mg kg−1) on the kidney in 13 healthy individuals. METHODS In plasma and urine samples, ciclosporin and 15-F2t-isoprostane concentrations were assessed using HPLC-MS and metabolite profiles using 1H-NMR spectroscopy. RESULTS The maximum ciclosporin concentrations were 1489 ± 425 ng ml−1 (blood) and 2629 ± 1308 ng ml−1 (urine). The increase in urinary 15-F2t-isoprostane observed 4 h after administration of ciclosporin indicated an increase in oxidative stress. 15-F2t-isoprostane concentrations were on average 2.9-fold higher after ciclosporin than after placebo (59.8 ± 31.2 vs. 20.9 ± 19.9 pg mg−1 creatinine, P < 0.02). While there were no conclusive changes in plasma 15-F2t-isoprostane concentrations or metabolite patterns, non-targeted metabolome analysis using principal components analysis and partial least square fit analysis revealed significant changes in urine metabolites typically associated with negative effects on proximal tubule cells. The major metabolites that differed between the 4 h urine samples after ciclosporin and placebo were citrate, hippurate, lactate, TMAO, creatinine and phenylalanine. CONCLUSION Changes in urine metabolite patterns as a molecular marker are sufficiently sensitive for the detection of the negative effects of ciclosporin on the kidney after a single oral dose. PMID:20653677

  19. Dose Responsive Effects of Subcutaneous Pentosan Polysulfate Injection in Mucopolysaccharidosis Type VI Rats and Comparison to Oral Treatment

    PubMed Central

    Frohbergh, Michael; Ge, Yi; Meng, Fanli; Karabul, Nesrin; Solyom, Alexander; Lai, Alon; Iatridis, James; Schuchman, Edward H.; Simonaro, Calogera M.

    2014-01-01

    Background We previously demonstrated the benefits of daily, oral pentosan polysulfate (PPS) treatment in a rat model of mucopolysaccharidosis (MPS) type VI. Herein we compare these effects to once weekly, subcutaneous (sc) injection. The bioavailability of injected PPS is greater than oral, suggesting better delivery to difficult tissues such as bone and cartilage. Injected PPS also effectively treats osteoarthritis in animals, and has shown success in osteoarthritis patients. Methodology/Principal Findings One-month-old MPS VI rats were given once weekly sc injections of PPS (1, 2 and 4 mg/kg, human equivalent dose (HED)), or daily oral PPS (4 mg/kg HED) for 6 months. Serum inflammatory markers and total glycosaminoglycans (GAGs) were measured, as were several histological, morphological and functional endpoints. Overall, weekly sc PPS injections led to similar or greater therapeutic effects as daily oral administration. Common findings between the two treatment approaches included reduced serum inflammatory markers, improved dentition and skull lengths, reduced tracheal deformities, and improved mobility. Enhanced effects of sc treatment included GAG reduction in urine and tissues, greater endurance on a rotarod, and better improvements in articular cartilage and bone in some dose groups. Optimal therapeutic effects were observed at 2 mg/kg, sc. No drug-related increases in liver enzymes, coagulation factor abnormalities or other adverse effects were identified following 6 months of sc PPS administration. Conclusions Once weekly sc administration of PPS in MPS VI rats led to equal or better therapeutic effects than daily oral administration, including a surprising reduction in urine and tissue GAGs. No adverse effects from sc PPS administration were observed over the 6-month study period. PMID:24964042

  20. Comparative Study of the Efficacy and Tolerability of Secnidazole Suspension (single dose) and Tinidazole Suspension (two days dosage) in the Treatment of Amebiasis in Children.

    PubMed

    Salles; Bechara; Tavares; Martins; Sobrinho; Dietrich-Neto; Costa

    1999-04-01

    Amebiasis caused by Entamoeba histolytica may be considered the most aggressive parasitic disease affecting human intestine, causing acute amoebic colitis and extra-intestinal diseases of high morbidity and mortality. 5-nitroimidazoles are the drugs of choice. In this multicenter, open and random clinical trial, the efficacy and tolerability of secnidazole suspension in a single oral dose of 1ml/kg was compared with 0.5ml/kg doses of tinidazole suspension given for 2 consecutive days to 303 Entamoeba histolytica-positive children aged 2 to 13. Patients with extra-intestinal complications were excluded from the study. Clinical and parasitological follow-up using the Faust and Kato-Katz method were carried out 7, 14, and 21 days after treatment. Clinical improvement/cure was observed in 93% of the patients in the secnidazole group and 91% in the tinidazole group. Parasitological success was reported for 77% and 63% of the secnidazole and tinidazole patients, respectively, showing a significant statistical difference between the two groups (p=0.007). Both drugs were well tolerated, and the adverse effects reported were mild, consisting mainly of digestive disturbances. This comparative study showed that a single oral dose of 1ml/kg of secnidazole produced a significantly higher parasitological cure rate than 2 doses of tinidazole. Secnidazole is a safe and effective drug for the treatment of uncomplicated intestinal amebiasis. PMID:11098194

  1. Variable dose rate single-arc IMAT delivered with a constant dose rate and variable angular spacing

    NASA Astrophysics Data System (ADS)

    Tang, Grace; Earl, Matthew A.; Yu, Cedric X.

    2009-11-01

    Single-arc intensity-modulated arc therapy (IMAT) has gained worldwide interest in both research and clinical implementation due to its superior plan quality and delivery efficiency. Single-arc IMAT techniques such as the Varian RapidArc™ deliver conformal dose distributions to the target in one single gantry rotation, resulting in a delivery time in the order of 2 min. The segments in these techniques are evenly distributed within an arc and are allowed to have different monitor unit (MU) weightings. Therefore, a variable dose-rate (VDR) is required for delivery. Because the VDR requirement complicates the control hardware and software of the linear accelerators (linacs) and prevents most existing linacs from delivering IMAT, we propose an alternative planning approach for IMAT using constant dose-rate (CDR) delivery with variable angular spacing. We prove the equivalence by converting VDR-optimized RapidArc plans to CDR plans, where the evenly spaced beams in the VDR plan are redistributed to uneven spacing such that the segments with larger MU weighting occupy a greater angular interval. To minimize perturbation in the optimized dose distribution, the angular deviation of the segments was restricted to <=± 5°. This restriction requires the treatment arc to be broken into multiple sectors such that the local MU fluctuation within each sector is reduced, thereby lowering the angular deviation of the segments during redistribution. The converted CDR plans were delivered with a single gantry sweep as in the VDR plans but each sector was delivered with a different value of CDR. For four patient cases, including two head-and-neck, one brain and one prostate, all CDR plans developed with the variable spacing scheme produced similar dose distributions to the original VDR plans. For plans with complex angular MU distributions, the number of sectors increased up to four in the CDR plans in order to maintain the original plan quality. Since each sector was delivered

  2. Pharmacokinetic study of enrofloxacin in Nile tilapia (Oreochromis niloticus) after a single oral administration in medicated feed.

    PubMed

    Teles, J A; Castello Branco, L C; Del Bianchi, M; Pilarski, F; Reyes, F G R

    2016-04-01

    The objective of this study was to evaluate the disposition kinetics of enrofloxacin (ENR) in the plasma and its distribution in the muscle tissue of Nile tilapia (Oreochromis niloticus) after a single oral dose of 10 mg/kg body weight via medicated feed. The fish were kept at a temperature between 28 and 30 °C. The collection period was between 30 min and 120 h after administration of the drug. The samples were analyzed by high-performance liquid chromatography with a fluorescence detector (HPLC-FLD). The ENR was slowly absorbed and eliminated from the plasma (Cmax = 1.24 ± 0.37 μg/mL; Tmax = 8 h; T1/2Ke  = 19.36 h). ENR was efficiently distributed in the muscle tissue and reached maximum values (2.17 ± 0.74 μg/g) after 8 h. Its metabolite, ciprofloxacin (CIP), was detected and quantified in the plasma (0.004 ± 0.005 μg/mL) and muscle (0.01 ± 0.011 μg/g) for up to 48 h. After oral administration, the mean concentration of ENR in the plasma was well above the minimum inhibitory concentrations (MIC50 ) for most bacteria already isolated from fish except for Streptococcus spp. This way the dose used in this study allowed for concentrations in the blood to treat the diseases of tilapia. PMID:26270353

  3. DNA damage in rats after a single oral exposure to diesel exhaust particles.

    PubMed

    Danielsen, Pernille Høgh; Risom, Lotte; Wallin, Håkan; Autrup, Herman; Vogel, Ulla; Loft, Steffen; Møller, Peter

    2008-01-01

    The gastrointestinal route of exposure to particulate matter is important because particles are ingested via contaminated foods and inhaled particles are swallowed when removed from the airways by the mucociliary clearance system. We investigated the effect of an intragastric administration by oral gavage of diesel exhaust particles (DEP) in terms of DNA damage, oxidative stress and DNA repair in colon epithelial cells, liver, and lung of rats. Eight rats per group were exposed to Standard Reference Material 2975 at 0.064 or 0.64 mg/kg bodyweight for 6 and 24 h. Increased levels of 8-oxo-7,8-dihydro-2'-deoxyguanosine lesions were observed at the highest dose after 6 and 24 h in all three organs. 8-Oxo-7,8-dihydro-2'-deoxyguanosine is repaired by oxoguanine DNA glycosylase 1 (OGG1); upregulation of this repair system was observed as elevated pulmonary OGG1 mRNA levels after 24 h at both doses of DEP, but not in the colon and liver. A general response of the antioxidant defence system is further indicated by elevated levels of heme oxygenase 1 mRNA in the liver and lung 24 h after administration. The level of bulky DNA adducts was increased in liver and lung at both doses after 6 and 24h (DNA adducts in colon epithelium were not investigated). In summary, DEP administered via the gastrointestinal tract at low doses relative to ambient exposure generates DNA damage and increase the expression of defence mechanisms in organs such as the lung and liver. The oral exposure route should be taken into account in risk assessment of particulate matter. PMID:17764705

  4. Tumor Induction in Mice After Localized Single- or Fractionated-Dose Irradiation: Differences in Tumor Histotype and Genetic Susceptibility Based on Dose Scheduling

    SciTech Connect

    Edmondson, Elijah F.; Hunter, Nancy R.; Weil, Michael M.; Mason, Kathryn A.

    2015-07-15

    Purpose: To investigate differences in tumor histotype, incidence, latency, and strain susceptibility in mice exposed to single-dose or clinically relevant, fractioned-dose γ-ray radiation. Methods and Materials: C3Hf/Kam and C57BL/6J mice were locally irradiated to the right hindlimb with either single large doses between 10 and 70 Gy or fractionated doses totaling 40 to 80 Gy delivered at 2-Gy/d fractions, 5 d/wk, for 4 to 8 weeks. The mice were closely evaluated for tumor development in the irradiated field for 800 days after irradiation, and all tumors were characterized histologically. Results: A total of 210 tumors were induced within the radiation field in 788 mice. An overall decrease in tumor incidence was observed after fractionated irradiation (16.4%) in comparison with single-dose irradiation (36.1%). Sarcomas were the predominant postirradiation tumor observed (n=201), with carcinomas occurring less frequently (n=9). The proportion of mice developing tumors increased significantly with total dose for both single-dose and fractionated schedules, and latencies were significantly decreased in mice exposed to larger total doses. C3Hf/Kam mice were more susceptible to tumor induction than C57BL/6J mice after single-dose irradiation; however, significant differences in tumor susceptibilities after fractionated radiation were not observed. For both strains of mice, osteosarcomas and hemangiosarcomas were significantly more common after fractionated irradiation, whereas fibrosarcomas and malignant fibrous histiocytomas were significantly more common after single-dose irradiation. Conclusions: This study investigated the tumorigenic effect of acute large doses in comparison with fractionated radiation in which both the dose and delivery schedule were similar to those used in clinical radiation therapy. Differences in tumor histotype after single-dose or fractionated radiation exposures provide novel in vivo evidence for differences in tumor

  5. A novel series of potent and selective PDE5 inhibitors with potential for high and dose-independent oral bioavailability.

    PubMed

    Allerton, Charlotte M N; Barber, Christopher G; Beaumont, Kevin C; Brown, David G; Cole, Susan M; Ellis, David; Lane, Charlotte A L; Maw, Graham N; Mount, Natalie M; Rawson, David J; Robinson, Colin M; Street, Stephen D A; Summerhill, Nicholas W

    2006-06-15

    Sildenafil (5-[2-ethoxy-5-(4-methyl-1-piperazinylsulfonyl)phenyl]-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one), a potent and selective phosphodiesterase type 5 (PDE5) inhibitor, provided the first oral treatment for male erectile dysfunction. The objective of the work reported in this paper was to combine high levels of PDE5 potency and selectivity with high and dose-independent oral bioavailability, to minimize the impact on the C(max) of any interactions with coadministered drugs in the clinic. This goal was achieved through identification of a lower clearance series with a high absorption profile, by replacing the 5'-piperazine sulfonamide in the sildenafil template with a 5'-methyl ketone. This novel series provided compounds with low metabolism in human hepatocytes, excellent caco-2 flux, and the potential for good aqueous solubility. The in vivo oral and iv pharmacokinetic profiles of example compounds confirmed the high oral bioavailability predicted from these in vitro screens. 5-(5-Acetyl-2-butoxy-3-pyridinyl)-3-ethyl-2-(1-ethyl-3-azetidinyl)-2,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one (2) was selected for progression into the clinic. PMID:16759100

  6. Effect of steady-state enoxacin on single-dose pharmacokinetics of roflumilast and roflumilast N-oxide.

    PubMed

    Lahu, Gezim; Nassr, Nassr; Herzog, Rolf; Elmlinger, Martin; Ruth, Peter; Hinder, Markus; Huennemeyer, Andreas

    2011-04-01

    Roflumilast is an oral phosphodiesterase 4 (PDE4) inhibitor for the treatment of chronic obstructive pulmonary disease (COPD). It is metabolized by CYP1A2 and CYP3A4 to its primary metabolite, roflumilast N-oxide, through which >90% total PDE4 inhibitory activity (tPDE4i) is mediated. Fluoroquinolones, of which enoxacin is the most potent CYP1A2 inhibitor, are used to treat COPD exacerbations. This phase I, open, nonrandomized, fixed-sequence, 2-period study evaluated the effects of steady-state enoxacin on the single-dose pharmacokinetics of roflumilast and roflumilast N-oxide. Twenty healthy participants received roflumilast, 500 µg once daily, on days 1 and 12, and enoxacin, 400 mg twice daily, on days 7 to 18. Pharmacokinetic profiles were obtained for days 1 to 6 and 12 to 19. The safety and tolerability of all treatments were also assessed. In 19 evaluable participants, coadministration led to 56% higher mean systemic exposure, 20% higher mean peak concentrations, and 36% lower mean apparent oral clearance compared with roflumilast alone. For roflumilast N-oxide, 23% higher mean systemic exposure and 14% lower mean peak concentrations were seen after coadministration. Roflumilast was well tolerated both alone and in combination with enoxacin. A weak interaction was shown between roflumilast and enoxacin, as mean tPDE4i increased by 25%, but is unlikely to have clinical relevance.

  7. Benzodiazepine whole blood concentrations in cases with positive oral fluid on-site screening test results using the DrugWipe(®) single for benzodiazepines.

    PubMed

    Blencowe, Tom; Vimpari, Kari; Lillsunde, Pirjo

    2011-07-01

    Reliable on-site oral fluid screening devices are a useful and convenient means of policing traffic. In Finland, benzodiazepines represent a particular challenge to traffic safety. This study presents a retrospective examination of toxicological analysis results from whole blood in cases which gave a positive screening result for benzodiazepines in oral fluid using the DrugWipe Single device (Securetec). Use of oral fluid on-site screening tests and blood confirmation analyses reflects the real situation in many countries. The data were compiled from the databases of Alcohol and Drug Analytics Unit at the National Institute for Health and Welfare. Confirmation analysis results in whole blood were obtained using gas chromatography-mass spectrometry. Data were from 224 real cases in which the Finnish police had conducted a DrugWipe Single benzodiazepines test on drivers suspected of driving under the influence of drugs (DUID). The benzodiazepine concentrations encountered in positive oral fluid screening cases in this study indicate that the device is able to detect these substances even at relatively low levels. However, the DrugWipe device does not enable any distinction between therapeutic use and harmful use of benzodiazepines at higher doses.

  8. Dose-related immunohistochemical and ultrastructural changes after oral methylphenidate administration in cerebrum and cerebellum of the rat.

    PubMed

    Bahcelioglu, Meltem; Gozil, Rabet; Take, Gulnur; Elmas, Cigdem; Oktem, Hale; Kadioglu, Dural; Calguner, Engin; Erdogan, Deniz; Sargon, Mustafa F; Yazici, A Canan; Tas, Murat; Bardakci, Yesim; Senol, Selahattin

    2009-01-01

    Methylphenidate is a piperidine derivative and is the drug most often used to treat attention deficit/hyperactivity disorder of children and young adults. Our aim is to investigate dose-dependent dopamine-2 receptor and glial fibrillary acidic protein expression and ultrastructural changes of the rat brain, to demonstrate possible toxicity of the long-term and high dose use of the methylphenidate. In this study, 27 female prepubertal Wistar albino rats, divided into three different dose groups (5, 10 and 20 mg/kg) were treated orally with methylphenidate dissolved in saline solution for 5 days per week during 3 months. At the end of the third month, tissues were removed and sections were collected for immunohistochemical and ultrastructural studies. We believe that methylphenidate causes dose-related activation of the dopaminergic system in several brain regions especially in ventral tegmental area and also causing neuronal degeneration and capillary wall structural changes such as basal membrane thickness and augmentation of the pinostatic vesicle in the endothelial cells. Also, increased dose of Ritalin is inducing astrocytes hypertrophy especially astrogliosis in pia-glial membrane and this is the result of the degenerative changes in prefrontal cortex region due to high dose methylphenidate administration. The dose-related accumulation of the astrocytes in capillary wall might well be a consequence of the need for nutrition of the neuronal tissue, due to transport mechanism deficiency related to neuronal and vascular degeneration. Thus, we believe that the therapeutic dose of methylphenidate must be kept in minimum level to prevent ultrastructural changes.

  9. Bortezomib in combination with low-dose oral melphalan, dexamethasone and thalidomide for relapsed elderly patients with multiple myeloma

    PubMed Central

    Azarm, Taleb; Akbari, Mojtaba; Azarm, Arezo; Mohager, Hamid

    2012-01-01

    BACKGROUND: The aim of the study was to assess the effects of combination of bortezomib moderate dose and continuous oral low dose melphalan and thalidomide and dexamethasone (BMTD regimen) in elderly patients aged ≥ 65 years with relapsed multiple myeloma (MM). METHODS: Twenty four patients with advanced MM were enrolled to receive eight 3-week treatment cycles with bortezomib 1.3 mg/m2 on days 1, 4, 8, and 11 followed by three 5-week cycles with bortezomib 1.3 mg/m2 on days 1, 8, 15, and 22. Within all cycles, dexamethasone 24 mg/d was given intravenously on the day of bortezomib injection and the day thereafter. In addition, patients received oral treatment of melphalan at a dose of 5 mg/d continuously for twenty days for every cycle. RESULTS: Mean age of study patients was 72.8 ± 6.4 years. All patients that completed at least one treatment cycle were evaluated for response. Complete, partial, and minor responses occurred in 19%, 65% and 6% of patients, respectively. Overall response rate was 90% (efficacy analysis). CONCLUSIONS: This study demonstrated potent in vivo activity of combination therapy with BMTD regimen in patients with relapsed MM, with an acceptable safety profile and high overall response rate. PMID:23248651

  10. Effect of a single dose of lactase on symptoms and expired hydrogen after lactose challenge in lactose-intolerant subjects.

    PubMed

    Sanders, S W; Tolman, K G; Reitberg, D P

    1992-06-01

    The effect of a single dose or oral lactase on symptoms, breath hydrogen concentration, and glucose absorption in lactose-intolerant subjects challenged with lactose was studied. Volunteers underwent a lactose challenge test; those whose breath hydrogen concentrations increased 20 ppm or more and who met other criteria were admitted as subjects. After fasting, the subjects were given three chewable lactase tablets (total lactase dose, 9900 FCC units) or placebo tablets in a randomized, double-blind, crossover manner. The subjects also consumed 8 oz of whole milk in which 37.5 g of lactose powder was dissolved (total lactose content, 50 g). The washout period between lactose challenges was at least one week. Breath hydrogen and plasma glucose concentrations were measured before and at intervals after the challenges, and the subjects completed symptom-evaluation questionnaires every eight hours for four days. Twenty-four subjects completed the study. The maximum mean breath hydrogen concentration was significantly lower after lactase treatment than after placebo treatment. In 21 subjects, the area under the hydrogen concentration-time curve (AUC) was lower after lactase than after placebo; three subjects had hydrogen AUCs more than 300 ppm.hr lower. There were no significant differences in plasma glucose levels. Subjective ratings of the severity of abdominal cramping, belching, flatulence, and diarrhea were lower during the first eight hours after challenge in lactase-treated subjects; ratings for bloating were lower during the next eight hours. Single doses of a chewable lactase tablet reduced the concentration of expired hydrogen and symptoms of lactose intolerance after a lactose challenge.

  11. A randomized comparative trial of two low-dose oral isotretinoin regimens in moderate to severe acne vulgaris

    PubMed Central

    Dhaked, Daulat Ram; Meena, Ram Singh; Maheshwari, Anshul; Agarwal, Uma Shankar; Purohit, Saroj

    2016-01-01

    Background: Oral isotretinoin is highly effective in all forms and grades of acne, even in lower dosages (<0.5 mg/kg/day). There is a paucity of comparative data on the various low-dose regimens of oral isotretinoin in the Indian literature. Objectives: To assess and compare the efficacy and tolerability of two low-dose oral isotretinoin treatment regimens (20 mg daily and 20 mg alternate days) in moderate to severe acne vulgaris. Materials and Methods: A total of 240 patients with moderate to severe acne vulgaris were selected and randomized into two groups and treated with a fixed dose of 20 mg of isotretinoin (Group A - daily and Group B - alternate days) for 24 weeks and followed up for 12 weeks post therapy. Results: A total of 234 patients completed the study. At the end of therapy, decrease in the total acne loads up to 98.99% (Group A) and 97.69% (Group B) was achieved from the baseline (P < 0.01), excellent response was observed in 98.3% (Group A) and 93.96% (Group B) patients (P = 0.166). In the severe acne, Group A performed significantly better than Group B until the end of 36 weeks. While in the moderate acne, significant difference in the response between both groups was observed only up to 12 weeks. No serious side effect was observed. Conclusion: Both isotretinoin regimens were well tolerated and found to be an effective treatment for moderate to severe acne vulgaris. However, in moderate acne 20 mg alternate day regimen may be preferred. A 20 mg daily regimen is a better choice for severe acne in terms of response. Limitation: Small sample size and short follow-up period. PMID:27730033

  12. Repeated oral dosing with Listeria monocytogenes in mice as a model of central nervous system listeriosis in man.

    PubMed

    Altimira, J; Prats, N; López, S; Domingo, M; Briones, V; Domínguez, L; Marco, A

    1999-08-01

    Human listeriosis is a food-borne disease of immunosuppressed or previously healthy adults. The repeated oral administration of a sublethal dose (5x10(9)colony-forming units) of Listeria monocytogenes for 7 or 10 consecutive days led to the development of severe central nervous system (CNS) lesions in 25% of experimental mice. Histopathological examination of the brain revealed rhombencephalitis and ventriculitis as two distinct inflammatory patterns, resembling those seen in human listeriosis. This model would seem to be potentially useful for research on pathogenesis, predisposing factors and therapy in CNS listeriosis in man. 1999 W.B. Saunders and Company Ltd.

  13. Folate supplementation induces differential dose-dependent modulation of proliferative phenotypes among cancerous and noncancerous oral cell lines in vitro.

    PubMed

    McCabe, Jonathan; Chang, Sarah; Hajibandeh, Jeffrey; Tran, Michael D; Meeder, Colby A; Sharma, Kanika; Nguyen, Dieu-Hoa; Moody, Michael; Keiserman, Mark A; Bergman, Christine J; Kingsley, Karl

    2010-12-01

    Sufficient folate intake confers positive health benefits, while deficiency is linked with many health problems. Although the US policy of dietary folic acid fortification has reduced the incidence of these deficiency-related health problems, recent evidence has demonstrated an association between folic acid supplementation and increased colorectal cancer incidence. Few studies have explored the possibility that folate affects other slowly developing cancers. This study sought to determine whether folic acid supplementation is sufficient to alter the growth and development of existing oral cancers. A series of in vitro growth, viability, and adhesion assays were performed using the well-characterized human oral squamous cell carcinoma cell lines, CAL27 and SCC25, to determine the effects of folic acid supplementation. Folic acid administration significantly stimulated CAL27 and SCC25 proliferation in a dose-dependent manner, but it was not sufficient to increase proliferation at any concentration tested in the normal control cell line, HGF-1. Neither oral cancer cell line harbored the common C677T DNA polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene, which might reduce folate bioavailability. Overexpression of p53 mRNA was observed in both cancerous cell lines, but it was differentially altered by folic acid administration in only SCC25 cells. These findings suggest folic acid administration may significantly alter growth of oral cancers in vitro via p53-dependent and p53-independent pathways. As oral cancer rates continue to rise in specific geographic areas, and among specific subsets of the US population, understanding environmental mediators, such as folic acid supplementation, becomes increasingly important for nutrition and public health scientists.

  14. Urodynamic and haemodynamic effects of a single oral administration of ephedrine or phenylpropanolamine in continent female dogs.

    PubMed

    Noël, Stéphanie; Massart, Laurent; Hamaide, Annick

    2012-04-01

    This study investigated the effects of a single oral administration of ephedrine (2 mg/kg) or phenylpropanolamine (PPA) (1.5 mg/kg) on the vesico-urethral and cardiovascular functions in continent female dogs. Urethral pressure profilometry (UPP), arterial blood pressures and heart rate were measured in five control dogs and after single-dose treatment with ephedrine or PPA at T(0), T(2h), T(4h), T(6h), T(12h), T(18h) and T(24h). UPPs were performed under propofol anaesthesia and other measurements were performed on awake dogs. A telemetric urodynamic investigation was performed on three additional dogs for 24 h after the administration of each drug. Urethral pressures increased over 4-6 h and urethral functional lengths increased 2-6h after administration of both drugs. During micturition, a decrease in detrusor pressure coupled with an increase in bladder volume was observed after ephedrine administration and there was also an increase in bladder volume after PPA had been given. With both drugs increased arterial blood pressures at 4-6 h were compensated by a decreased heart rate over 12 h. Urethral function was improved after both ephedrine and PPA, and bladder function also improved during micturition following ephedrine.

  15. Impact of dose size in single fraction spatially fractionated (grid) radiotherapy for melanoma

    SciTech Connect

    Zhang, Hualin E-mail: hualinzhang@yahoo.com; Zhong, Hualiang; Barth, Rolf F.; Cao, Minsong; Das, Indra J.

    2014-02-15

    Purpose: To evaluate the impact of dose size in single fraction, spatially fractionated (grid) radiotherapy for selectively killing infiltrated melanoma cancer cells of different tumor sizes, using different radiobiological models. Methods: A Monte Carlo technique was employed to calculate the 3D dose distribution of a commercially available megavoltage grid collimator in a 6 MV beam. The linear-quadratic (LQ) and modified linear quadratic (MLQ) models were used separately to evaluate the therapeutic outcome of a series of single fraction regimens that employed grid therapy to treat both acute and late responding melanomas of varying sizes. The dose prescription point was at the center of the tumor volume. Dose sizes ranging from 1 to 30 Gy at 100% dose line were modeled. Tumors were either touching the skin surface or having their centers at a depth of 3 cm. The equivalent uniform dose (EUD) to the melanoma cells and the therapeutic ratio (TR) were defined by comparing grid therapy with the traditional open debulking field. The clinical outcomes from recent reports were used to verify the authors’ model. Results: Dose profiles at different depths and 3D dose distributions in a series of 3D melanomas treated with grid therapy were obtained. The EUDs and TRs for all sizes of 3D tumors involved at different doses were derived through the LQ and MLQ models, and a practical equation was derived. The EUD was only one fifth of the prescribed dose. The TR was dependent on the prescribed dose and on the LQ parameters of both the interspersed cancer and normal tissue cells. The results from the LQ model were consistent with those of the MLQ model. At 20 Gy, the EUD and TR by the LQ model were 2.8% higher and 1% lower than by the MLQ, while at 10 Gy, the EUD and TR as defined by the LQ model were only 1.4% higher and 0.8% lower, respectively. The dose volume histograms of grid therapy for a 10 cm tumor showed different dosimetric characteristics from those of conventional

  16. A randomized double-blind trial of two low dose combined oral contraceptives.

    PubMed

    Bounds, W; Vessey, M; Wiggins, P

    1979-04-01

    Fifty-five women using Loestrin-20 (20 microgram ethinyl oestradiol and 1 mg norethisterone acetate) as an oral contraceptive have been compared with a like number using Microgynon-30 (30 microgram ethinyl oestradiol and 150 microgram levonorgestrel) in a randomized, double-blind trial. Despite the small sample size, the main finding in the trial is clear-cut; Loestrin-20 provides poor cycle control and is thus less acceptable as an oral contraceptive than Microgynon-30. Although there is also a suggestion that Loestrin-20 may be less effective than Microgynon-30, the difference in the accidental pregnancy rates is not statistically significant.

  17. Dose Control System in the Optima XE Single Wafer High Energy Ion Implanter

    SciTech Connect

    Satoh, Shu; Yoon, Jongyoon; David, Jonathan

    2011-01-07

    Photoresist outgassing can significantly compromise accurate dosimetry of high energy implants. High energy implant even at a modest beam current produces high beam powers which create significantly worse outgassing than low and medium energy implants and the outgassing continues throughout the implant due to the low dose in typical high energy implant recipes. In the previous generation of high energy implanters, dose correction by monitoring of process chamber pressure during photoresist outgassing has been used. However, as applications diversify and requirements change, the need arises for a more versatile photoresist correction system to match the versatility of a single wafer high energy ion implanter. We have successfully developed a new dosimetry system for the Optima XE single wafer high energy ion implanter which does not require any form of compensation due to the implant conditions. This paper describes the principles and performance of this new dose system.

  18. Single-dose radiation therapy for prevention of heterotopic ossification after total hip arthroplasty

    SciTech Connect

    Healy, W.L.; Lo, T.C.; Covall, D.J.; Pfeifer, B.A.; Wasilewski, S.A. )

    1990-12-01

    Single-dose radiation therapy was prospectively evaluated for its efficacy in prevention of heterotopic ossification in patients at high risk after total hip arthroplasty. Thirty-one patients (34 hips) were treated between 1981 and 1988. Risk factors for inclusion in the protocol included prior evidence of heterotopic ossification, ankylosing spondylitis, and diffuse idiopathic skeletal hyperostosis. Patients with hypertrophic osteoarthritis or traumatic arthritis with osteophytes were not included. Operations on 34 hips included 19 primary total and 11 revision total hip arthroplasties and 4 excisions of heterotopic ossification. All patients received radiotherapy to the hip after operation with a single dose of 700 centigray. Radiotherapy is recommended on the first postoperative day. After this single-dose radiation treatment, no patient had clinically significant heterotopic ossification. Recurrent disease developed in two hips (6%), as seen on radiography (grades 2 and 3). This series documents a 100% clinical success rate and a 94% radiographic success rate in preventing heterotopic ossification in patients at high risk after total hip arthroplasty. Single-dose radiotherapy is as effective as other radiation protocols in preventing heterotopic ossification after total hip arthroplasty. It is less expensive and easier to administer than multidose radiotherapy.

  19. Single dose testosterone administration alleviates gaze avoidance in women with Social Anxiety Disorder.

    PubMed

    Enter, Dorien; Terburg, David; Harrewijn, Anita; Spinhoven, Philip; Roelofs, Karin

    2016-01-01

    Gaze avoidance is one of the most characteristic and persistent social features in people with Social Anxiety Disorder (SAD). It signals social submissiveness and hampers adequate social interactions. Patients with SAD typically show reduced testosterone levels, a hormone that facilitates socially dominant gaze behavior. Therefore we tested as a proof of principle whether single dose testosterone administration can reduce gaze avoidance in SAD. In a double-blind, within-subject design, 18 medication-free female participants with SAD and 19 female healthy control participants received a single dose of 0.5mg testosterone and a matched placebo, at two separate days. On each day, their spontaneous gaze behavior was recorded using eye-tracking, while they looked at angry, happy, and neutral facial expressions. Testosterone enhanced the percentage of first fixations to the eye-region in participants with SAD compared to healthy controls. In addition, SAD patients' initial gaze avoidance in the placebo condition was associated with more severe social anxiety symptoms and this relation was no longer present after testosterone administration. These findings indicate that single dose testosterone administration can alleviate gaze avoidance in SAD. They support theories on the dominance enhancing effects of testosterone and extend those by showing that effects are particularly strong in individuals featured by socially submissive behavior. The finding that this core characteristic of SAD can be directly influenced by single dose testosterone administration calls for future inquiry into the clinical utility of testosterone in the treatment of SAD.

  20. MIND+ system; More universal dose patterns by single-step ion implantation

    NASA Astrophysics Data System (ADS)

    Okamoto, Yasuharu; Ninomiya, Shiro; Ochi, Akihiro; Ueno, Yusuke; Yamada, Tatsuya; Kimura, Yasuhiko; Kudo, Tetsuya; Koike, Masazumi; Suetsugu, Noriyuki; Ookita, Yoshiaki; Tsukihara, Mitsukuni; Sato, Fumiaki; Fuse, Genshu; Ueno, Kazuyoshi; Sugitani, Michiro

    2012-11-01

    Electrical characteristics of semi-conductor devices within a wafer are expected to be uniform based on control of the dose pattern during the ion implant process. SEN developed the MIND system (Mapping of Intentional Non-uniform Dosage), to provide such dose pattern control. This capability has been enhanced with MIND+. The new system provides improved two-dimensional dose pattern control with more degrees of freedom and greater accuracy than the original MIND system. In addition, MIND+ can generate practical dose patterns (see below) while using a single step implant. As a result, MIND+ provides a very powerful tool for yield enhancement without sacrificing throughput. This paper will provide more detail on the capabilities and practical applications of the MIND+ system.

  1. Single Intramuscular-dose Toxicity of Anti-inflammatory Pharmacopuncture in Rats

    PubMed Central

    Jung, Da-jung; Kim, Sung-chul; Lee, Hyung-geol; Choi, Yoo-min; Sin, Min-seop; Choi, Seok-woo; Hong, Seung-won; Song, Beom-yong; Kim, Jong-uk; Yook, Tae-han

    2013-01-01

    Objectives: This study was performed to analyze the toxicity of the test substance, anti-inflammatory pharmacopuncture (AIP), when used as a single intramuscular-dose in 6-week-old, male and female Sprague-Dawley rats and to find the lethal dose. Methods: The experiment was conducted at Biotoxtech according to Good Laboratory Practices. Twenty (20) female and 20 male Spague-Dawley rats were divided into 4 groups of five 5 female and 5 male animals per group. The rats in the three experimental groups received single intramuscular injections with 0.1-㎖, 0.5-㎖ and 1.0-㎖/animal doses of AIP, Groups 2, 3, and 4, respectively, and the control group, Group 1, received a single intramuscular injection with a 1.0-㎖ dose of normal saline. Clinical signs were observed and body weight measurements were carried out for 14 days following the injections. At the end of the observation period, hematology, clinical chemistry, histopathological tests and necropsy were performed on the injected parts. Results: No deaths occurred in any of the groups. Also, histopathological tests showed that AIP had no effect on the injected parts in terms of clinical signs, body weight, hematology, clinical chemistry, and necropsy. Conclusions: As a result of single intramuscular-dose tests of the test substance AIP in 4 groups of rats, the lethal dose for both males and females exceeded 1.0㎖/animal. Therefore, AIP is a relatively safe pharmacopuncture that can be used for treatment, but further studies should be performed. PMID:25780679

  2. Single- and multiple-dose pharmacokinetics of genistein capsules in healthy chinese subjects: A phase I, randomized, open-label study

    PubMed Central

    Zeng, Xing; Feng, Yi; Yang, Liu; Huang, Yu; Zhou, Dan; Sun, Jing; Liu, Yiming; Deng, Yuanhui

    2008-01-01

    Background: Genistein capsules are currently being developed to treat osteoporosis in China. Genistein is extracted from the fruit of Sophora japonica Leguminosae. Objective: The objective of this study was to assess the pharmacokinetics of genistein capsules after single and multiple oral doses in healthy Chinese subjects. Methods: This was a Phase I, randomized, open-label, single- and multiple- dose study in healthy Chinese adults (aged 19–40 years). In the single-dose study, subjects were randomly assigned in a 1:1:1 ratio to receive genistein 50, 100, or 300 mg (in 50-mg capsules). To assess the effect of food on the pharmacokinetics, subjects in the 50-mg group were equally randomized again into fasting and postprandial (genistein was administered after a high-fat breakfast) groups according to a 2-way cross-over design. A separate equal-sized group of subjects were administered genistein 50 mg on day 1 (single dose), received no treatment on days 2 and 3, and were administered genistein 50 mg QD for 6 days (days 4–9) to obtain a multiple-dose pharmacokinetic profile. Because genistein is converted so rapidly and completely to glucuronidated genistein after administration, plasma concentrations of glucuronidated genistein were determined using a validated high-performance liquid chromatography/ tandem mass spectrometry method. Drug tolerability was assessed by monitoring adverse events (AEs) and laboratory parameters. Results: The study enrolled 40 healthy subjects (24 men, 16 women; 10 each in the 50-, 100-, and 300-mg single-dose groups and 10 in the multiple-dose group). Three subjects voluntarily withdrew (2 in the 100-mg group and 1 in the 300-mg group) before study drug administration. Thirty-seven subjects (24 men, 13 women) completed the study and were included in the analysis. The mean (SD) values of the single-dose genistein 50-, 100-, and 300-mg groups were as follows: Tmax, 6.0 (2.4), 7.4 (2.4), and 5.6 (1.2) hours, respectively; tl/2, 13.0 (4

  3. Acute and chronic bioeffects of single and multiple doses of piezoelectric shockwaves (EDAP LT.01).

    PubMed

    Ryan, P C; Jones, B J; Kay, E W; Nowlan, P; Kiely, E A; Gaffney, E F; Butler, M R

    1991-02-01

    Piezoelectric second generation lithotriptors are an established means of administering extracorporeal shockwave lithotripsy (ESWL) enabling treatment to be performed without anaesthesia or analgesia, but higher shockwave doses and multiple or staged treatment are frequently required. The bioeffects of this modality of ESWL, therefore, require further assessment. Seven experimental groups of adult male rabbits were treated using the EDAP LT.01 in order to determine the acute and chronic bioeffects of clinical dose, excess dose, divided excess dose, high frequency and multiple treatment (X10) piezoelectric shockwaves (PSW). Renal function was measured before and after treatment using mercaptoacetyltriglycine (MAG 3) scans. Gross and histological morphological changes were assessed at one and 30 days following application of PSW. Application of single clinical dose PSW was not associated with any significant functional or morphological renal injury. Excess dose PSW caused transient gross renal contusion, which resolved in the majority of animals with no persistent microscopic abnormality. Divided excess dose PSW resulted in no gross or microscopic damage. High frequency PSW was associated with mild histological abnormality. Multiple PSW treatments caused small discrete fibrotic lesions in all cases, without any change in renal function.

  4. Acute tolerance to rate-decreasing effects of single doses of ethanol.

    PubMed

    Ginsburg, Brett C; Martinez, Gerardo; Friesenhahn, Gregory; Javors, Martin; Lamb, R J

    2008-06-01

    Acute tolerance occurs when behavioral impairment is greater at a given blood ethanol concentration (BAC) on the ascending versus descending limb of the BAC-time curve following administration of a single dose of ethanol, however studies utilizing learned behaviors have not been widely reported. We assessed acute tolerance to single doses of ethanol in five Lewis rats responding under a fixed-ratio (FR8) schedule of food presentation. Response rates for food during 1-min components (ending 2, 4, 11, 18, 33, and 57 min after ethanol administration) were determined, and BAC was measured immediately after each component using a rat breathalyzer. Ethanol (0.4, 0.6, 0.8, and 1.2 g/kg, i.p.) produced dose-related decreases in responding for food that tended to recover over time for all but the highest dose tested. Similarly, dose-related increases in BAC were also observed. Using either an analysis that expressed impairment per unit BAC on the ascending limb versus the descending limb (by assessing the area under the curve (AUC) for behavior and BAC on each limb), the slope of the function that relates the behavioral effect to BAC (each expressed as percent maximum effect), or a variant of the Mellanby method (hysteresis), acute tolerance was observed following a dose of 0.4 g/kg ethanol. Though behavior appeared to recover on the descending limb following higher doses (especially 0.6 and 0.8 g/kg), acute tolerance to these doses was not present. PMID:18328511

  5. Efficacy of mouth rinse in preventing oral mucositis in patients receiving high-dose cytarabine for allogeneic hematopoietic stem cell transplantation.

    PubMed

    Mori, Takehiko; Hasegawa, Kaori; Okabe, Ai; Tsujimura, Natsuki; Kawata, Yusuke; Yashima, Tomoko; Kobayashi, Naoko; Kondo, Sakiko; Aisa, Yoshinobu; Kato, Jun; Tsunoda, Kazuyuki; Nagai, Tetsuo; Nakagawa, Taneaki; Shigematsu, Naoyuki; Kubo, Atsushi; Ikeda, Yasuo; Okamoto, Shinichiro

    2008-12-01

    High-dose cytarabine is one of the major components of the conditioning regimen for hematopoietic stem cell transplantation (HSCT), and frequently causes severe oral mucositis. We have recently demonstrated that cytarabine is excreted into the saliva in patients receiving high-dose cytarabine, and proposed that it might locally and directly contribute to the development of oral mucositis. Therefore, this study was performed to assess whether removing the excreted cytarabine in the saliva by intensive mouth rinse during high-dose cytarabine infusion could reduce the incidence of oral mucositis. Fifteen patients with hematologic malignancies undergoing allogeneic HSCT who received total body irradiation (12 Gy) and high-dose cytarabine at a dose of 3 g/m(2) every 12 h for 4 days as a conditioning were evaluated. Patients were instructed to rinse their mouths using ice-cold water every 10 min, starting simultaneously with the 2-h cytarabine infusion and continuing up to 1 h after completion of each infusion. Oral mucositis was graded on a daily basis according to the National Cancer Institute, Common Toxicity Criteria. Thirty-five patients who previously underwent the same conditioning without mouth rinse served as controls. The incidence of Grades 2-3 and Grade 3 oral mucositis was significantly reduced in patients who performed mouth rinse as compared with the controls (40 vs. 80%, P = 0.009; 0 vs. 25. 7%, P = 0.02). In conclusion, mouth rinse during and shortly after high-dose cytarabine infusion could be an effective and inexpensive measure in reducing the incidence of moderate to severe oral mucositis caused by high-dose cytarabine. This finding strongly suggests the role of cytarabine excretion in the saliva in the development of cytarabine-associated oral mucositis.

  6. Clinical improvement in feline herpesvirus 1 infected cats by oral low dose of interleukin-12 plus interferon-gamma.

    PubMed

    Fiorito, Filomena; Cantiello, Antonietta; Granato, Giovanna Elvira; Navas, Luigi; Diffidenti, Carmine; De Martino, Luisa; Maharajan, Veeramani; Olivieri, Fabio; Pagnini, Ugo; Iovane, Giuseppe

    2016-10-01

    Feline herpesvirus 1 (FHV-1) is a widespread cat pathogen inducing rhinitis, conjunctivitis and corneal ulcers. To alleviate acute FHV-1-induced disease, antiviral agents are used often with antibiotics. But sometimes, these treatments, as well as conventional doses of cytokines have moderate efficacy and/or collateral effects. Herein we have investigated the effects of low dose interleukin (IL)-12 plus interferon (IFN)-gamma, prepared by Sequential Kinetic Activated (SKA), on the treatment of FHV-1 infection. Twenty-five, unvaccinated FHV-1-positive cats were recruited into a prospective, randomized, placebo-controlled, double-blinded clinical trial. Fifteen cats were treated for 6 months with oral low doses of SKA IL-12 plus IFN-gamma and 10 cats were treated with placebo. At 1, 6 and 12 months (follow-up) after the beginning of treatment, clinical assessment, PCR assay and blood count were carried out. At follow-up, in treated group, we observed significant (p<0.05) improvements in clinical signs and PCR became negative in 12/15 cats (80%). In placebo, 10/10 cats were PCR-positive, with improvements (30%) or worsening (70%) in clinical signs. Blood values were normal in both groups. Our results show that the low dose therapy, based on activated solutions of IL-12 plus IFN-gamma, represents a novel approach to treat FHV-1 infection in cats. PMID:27638118

  7. Disease control using low-dose-rate brachytherapy is unaffected by comorbid severity in oral cancer patients

    PubMed Central

    Yoshimura, R; Shibuya, H; Hayashi, K; Toda, K; Watanabe, H; Miura, M

    2011-01-01

    Objective The aim of this study was to evaluate the outcome and complications of low-dose-rate brachytherapy (LDR-BT) for oral cancer according to comorbidity. Methods The records of a total of 180 patients who received LDR-BT for T1-2N0M0 oral cancers between January 2005 and December 2007 were analysed. The comorbidities of the patients were retrospectively graded according to the Adult Comorbidity Evaluation-27, and the relationships between the comorbidity grades and survival, disease control and the incidence of complications were analysed. Results The 2 year overall survival rates of patients with no comorbidity, Grade 1, Grade 2 and Grade 3 comorbidity were 87%, 85%, 76% and 65%, respectively, and the reduction in the survival rate according to comorbid severity was significant in a univariate analysis (p = 0.032) but not in a multivariate analysis including other clinical factors. Cause-specific survival, locoregional control and local control were not related to the comorbidity grade, or any other clinical factors. Grade 2 or 3 complications developed in 27% of the patients. The incidence of complications was unrelated to the comorbidity grade. Conclusion The disease control of oral cancer and the incidence of complications after LDR-BT were not related to comorbid severity. LDR-BT is a useful and safe treatment for patients regardless of the presence of severe comorbidity. PMID:21224307

  8. Specific accumulation of orally administered redox nanotherapeutics in the inflamed colon reducing inflammation with dose-response efficacy.

    PubMed

    Vong, Long Binh; Mo, John; Abrahamsson, Bertil; Nagasaki, Yukio

    2015-07-28

    Although current medications for ulcerative colitis (UC) are effective to some extent, there are still some limitation of their use due to the non-specific distribution, drug metabolism in the gastrointestinal tract, and severe adverse effects. In our previous studies, we developed oral redox nanoparticles (RNP(O)) that specifically accumulated and scavenged overproduced reactive oxygen species (ROS) in an inflamed colon. However, the mechanism leading to specific accumulation of RNP(O) in an inflamed colon is still unclear. In this study, we investigated the cellular uptake of RNP(O) into ROS-treated epithelial colonic cells in vitro, and compared to the untreated cells, found a significantly increased uptake in ROS-treated cells. In vivo, we discovered that orally administered RNP(O) were not internalized into the cells of a normal colon. A significant amount of disintegrated RNP(O) was detected in the cells of an inflamed colon of dextran sodium sulfate (DSS)-induced colitis mice, resulting in scavenging of ROS and suppression of inflammation with low adverse effects. Furthermore, we confirmed a significant reduction of disease activity and a robust dose response efficacy following RNP(O) treatment in acute DSS-induced colitis mice, outperforming the positive control 5-aminosalicylic acid. Oral administration of RNP(O) is a promising approach to develop a new therapy for UC disease. PMID:25998050

  9. Sevoflurane-emergence agitation: Effect of supplementary low-dose oral ketamine premedication in preschool children undergoing dental surgery

    PubMed Central

    Khattab, Ahmed Metwally; El-Seify, Zeinab Ahmed

    2009-01-01

    Background and Objectives: The use of sevoflurane in pediatric anesthesia, which could enable a more rapid emergence and recovery, is complicated by the frequent occurrence of post-anesthesia agitation. This study aims to test the efficacy of adding a low dose of ketamine orally, as a supplement to the midazolam-based oral premedication for reducing sevoflurane-related emergence agitation. Materials and Methods: Ninety-two preschool children, aged between two and six years, with an American Society of Anesthesiologists physical status I or II, scheduled for elective dental filling and extractions under general anesthesia were included. The patients were allocated into two groups: Group M (46 patients) received oral midazolam 0.5 mg/kg, mixed with ibuprofen 10 mg/kg, while group KM (46 patients) received a similar premedication mixture, in addition to ketamine 2 mg/kg. The acceptance of the drug mixture, the onset of action, and the occurrence of vomiting were monitored over the next 30 minutes. Induction of anesthesia was carried out using sevoflurane 8 Vol% in 100% oxygen via face mask. Anesthesia was maintained with sevoflurane 1.5-2 Vol% in an oxygen-nitrous oxide mixture. After extubation, the standard scoring scale was used for assessing the quality of emergence. Agitation parameters were measured using a five-point scale. Agitated children were managed by giving intravenous increments of fentanyl 1 μg/ kg. The time of hospital discharge allowance was recorded. Results: Drug palatability, vomiting, and onset of action of premedication; showed no significant differences between both groups. Time of eye opening after discontinuation of sevoflurane showed no significant differences between both groups. Postoperative agitation score and rescue fentanyl consumption were higher in group M than in group KM on admission to the PACU (P < 0.01). The time of hospital discharge allowance in group M was longer than in group KM (P < 0.05). Conclusion: Adding a low dose of

  10. Oral high-dose medroxyprogesterone acetate (MPA) treatment: cortisol/MPA serum profiles in relation to breast cancer regression.

    PubMed

    Mahlke, M; Grill, H J; Knapstein, P; Wiegand, U; Pollow, K

    1985-01-01

    Medroxyprogesterone acetate (MPA), a potent synthetic progestin, has been widely used in the hormonal treatment of advanced breast cancer, but presently with varying dose schedules. The availability of a sensitive RIA-method for determination of serum MPA has stimulated the research on MPA serum levels in patients after repeated MPA administration. The aim of this study was to assay blood level profiles of MPA as well as of cortisol during repeated high-dose orally administered MPA. 34 patients with metastatic breast cancer were enrolled in this study. 12 patients died already within the first 4 weeks of MPA treatment due to multiple metastases. The dosage regimen based on the daily oral administration of 1,000 mg MPA suspension. During MPA treatment, a decrease of cortisol serum levels was observed in nearly all patients. Within the observation time of 8 months out of 22 evaluable cases 18.2% responded to the therapy (complete and partial response). No change was observed in 36.4% and progression in 45.5% of the patients. Within the remission (complete and partial) group, a good correlation between constant MPA serum levels above 150 ng/ml and remission was observed. But in the groups with no change and progression no such correlation could be observed.

  11. Impact of oral bisphenol A at reference doses on intestinal barrier function and sex differences after perinatal exposure in rats

    PubMed Central

    Braniste, Viorica; Jouault, Aurore; Gaultier, Eric; Polizzi, Arnaud; Buisson-Brenac, Claire; Leveque, Mathilde; Martin, Pascal G.; Theodorou, Vassilia; Fioramonti, Jean; Houdeau, Eric

    2009-01-01

    Bisphenol A (BPA), a chemical estrogen widely used in the food-packaging industry and baby bottles, is recovered in human fluids (0.1–10 nM). Recent studies have reported that BPA is hormonally active at low doses, emphasizing the debate of a risk for human health. Estrogen receptors are expressed in the colon, and although the major route of BPA exposure is food, the effects on gut have received no attention. We first examined the endocrine disrupting potency of BPA on colonic paracellular permeability (CPP), experimental colitis, and visceral sensitivity in ovariectomized rats orally exposed to 5 mg/kg/d BPA (i.e., the no observed adverse effect level), 50 μg/kg/d BPA (i.e., tolerable daily intake), or lower doses. BPA dose-dependently decreased basal CPP, with a half-maximal inhibitory dose of 5.2 μg/kg/d, 10-fold below the tolerable daily intake. This correlated with an increase in epithelial tight junction sealing, also observed in Caco-2 cells exposed to 10 nM BPA. When ovariectomized rats were fed with BPA at the no observed adverse effect level, the severity of colitis was reduced, whereas the same dose increased pain sensitivity to colorectal stimuli. We then examined the impact of perinatal exposure to BPA on intestinal permeability and inflammatory response in the offspring. In female rats, but not in male rats, perinatal BPA evoked a decrease of CPP in adulthood, whereas the proinflammatory response of colonic mucosa was strengthened. This study first demonstrates that the xenoestrogen BPA at reference doses influences intestinal barrier function and gut nociception. Moreover, perinatal exposure promotes the development of severe inflammation in adult female offspring only. PMID:20018722

  12. Intravenous Single-Dose Toxicity of Redaporfin-Based Photodynamic Therapy in Rodents

    PubMed Central

    Rocha, Luis B.; Schaberle, Fábio; Dąbrowski, Janusz M.; Simões, Sérgio; Arnaut, Luis G.

    2015-01-01

    We assessed the tolerability and safety in rodents of a single intravenous (i.v.) dose of redaporfin, a novel photosensitizer for Photodynamic Therapy (PDT) of cancer. Two approaches were used to evaluate acute toxicity: (i) a dose escalation study in BALB/c mice to evaluate the maximum tolerated dose of redaporfin; and (ii) a safety toxicology study in Wistar rats, of a single dose of redaporfin, with or without illumination, to evaluate possible signs of systemic toxicity. Redaporfin formulation was well tolerated by mice, with no signs of adverse reactions up to 75 mg/kg. In rats, there were no relevant changes, except for a significant, but transient, increase in the blood serum markers for hepatic function and muscle integrity, and also on neutrophil counts, observed after the application of light. The overall results showed that redaporfin-PDT is very well tolerated. No abnormalities were observed, including reactions at the injection site or skin phototoxicity, although the animals were maintained in normal indoor lighting. Redaporfin also showed a high efficacy in the treatment of male BALB/c mice with subcutaneously implanted colon (CT26) tumours. Vascular-PDT with 1.5 mg/kg redaporfin and a light dose of 74 J/cm2 led to the complete tumour regression in 83% of the mice. PMID:26670231

  13. SINGLE- VERSUS DOUBLE-DOSE RABIES VACCINATION IN CAPTIVE AFRICAN WILD DOGS (LYCAON PICTUS).

    PubMed

    Connolly, Maren; Thomas, Patrick; Woodroffe, Rosie; Raphael, Bonnie L

    2015-12-01

    The immune responses of 35 captive African wild dogs (Lycaon pictus) to an inactivated rabies virus vaccine were evaluated. Seventeen animals received one 1-ml dose of inactivated rabies vaccine administered intramuscularly, while 18 received two 1-ml doses given simultaneously but at different injection sites. Sera were collected from all animals prior to vaccination and intermittently from a subset of animals between 3 and 49 mo postvaccination. Rabies neutralizing serum antibody titers were measured by rapid fluorescent focus inhibition testing. Within 3 mo postvaccination, all 28 animals that were tested within that time period had seroconverted. Overall, titers were significantly higher among animals given two doses of vaccine than among those given a single dose, although this difference was no longer significant by 15 mo postvaccination. Regardless of initial dose, a single administration of inactivated rabies virus vaccine resulted in long-term elevation of titers in the African wild dogs in this study. In the two individuals followed for greater than 36 mo, both (one from each group) maintained detectable titers.

  14. SINGLE- VERSUS DOUBLE-DOSE RABIES VACCINATION IN CAPTIVE AFRICAN WILD DOGS (LYCAON PICTUS).

    PubMed

    Connolly, Maren; Thomas, Patrick; Woodroffe, Rosie; Raphael, Bonnie L

    2015-12-01

    The immune responses of 35 captive African wild dogs (Lycaon pictus) to an inactivated rabies virus vaccine were evaluated. Seventeen animals received one 1-ml dose of inactivated rabies vaccine administered intramuscularly, while 18 received two 1-ml doses given simultaneously but at different injection sites. Sera were collected from all animals prior to vaccination and intermittently from a subset of animals between 3 and 49 mo postvaccination. Rabies neutralizing serum antibody titers were measured by rapid fluorescent focus inhibition testing. Within 3 mo postvaccination, all 28 animals that were tested within that time period had seroconverted. Overall, titers were significantly higher among animals given two doses of vaccine than among those given a single dose, although this difference was no longer significant by 15 mo postvaccination. Regardless of initial dose, a single administration of inactivated rabies virus vaccine resulted in long-term elevation of titers in the African wild dogs in this study. In the two individuals followed for greater than 36 mo, both (one from each group) maintained detectable titers. PMID:26667524

  15. Effects of single-dose and fractionated cranial irradiation on rat brain accumulation of methotrexate

    SciTech Connect

    Kamen, B.A.; Moulder, J.E.; Kun, L.E.; Ring, B.J.; Adams, S.M.; Fish, B.L.; Holcenberg, J.S.

    1984-11-01

    The effects of single-dose and fractionated whole-brain irradiation on brain methotrexate (MTX) has been studied in a rat model. The amount of MTX present in the brain 24 hr after a single i.p. dose (100 mg/kg) was the same whether animals were sham irradiated or given a single dose of 2000 rads 6 or 48 hr prior to the drug (6.9, 8.3, and 6.8 pmol MTX/g, wet weight, respectively). Animals sham irradiated or given 2000 rads in 10 fractions over 11 days and treated with an average dose of 1.2 mg MTX/kg i.p. twice a week for 24 weeks did not differ significantly in their brain MTX concentration (7.9 and 8.3 pmol MTX/g, wet weight, respectively). Chronically MTX-treated animals became folate deficient whether they were irradiated or not (450 and 670 pmol folate/g, wet weight, brain in MTX-treated and control animals). Thus, MTX accumulates in the brain with acute or chronic administration, and this accumulation is not altered by this amount of brain irradiation.

  16. Kinetics and intrapulmonary disposition of tilmicosin after single and repeated oral bolus administrations to rabbits.

    PubMed

    Gallina, G; Lucatello, L; Drigo, I; Cocchi, M; Scandurra, S; Agnoletti, F; Montesissa, C

    2010-06-01

    Tilmicosin (TIM, Pulmotil) was administered to eight rabbits by oral gavage at a dose of 12.5 mg/kg body weight for 2, 5, and 7 days, and its plasma kinetics and intrapulmonary disposition were investigated. TIM concentrations in plasma samples collected after days 1 and 6 of treatment were measured by high-performance liquid chromatography with ultraviolet detection. The pharmacokinetic parameters, obtained by non-compartmental analysis of TIM plasma concentrations, did not show any significant variations between days 1 and 6. From the second day of treatment, TIM concentrations attained in lung tissue and pulmonary alveolar macrophages (PAM) exceeded those in plasma by 7- and 400-fold, respectively, and high levels were maintained in lung tissues during the entire treatment duration. After the first day of withdrawal, a fast decline in TIM levels in both plasma and lung tissue was observed, but in PAM, much higher concentrations were maintained after 3 days of TIM withdrawal.

  17. Single-dose Intravenous Toxicology Testing of Daebohwalryeok Pharmcopuncture in Sprague-Dawley Rats

    PubMed Central

    Sun, Seung-Ho; Park, Sunju; Jeong, Jong-Jin; Lee, Kwang-Ho; Yu, Jun-Sang; Seo, Hyung-Sik; Kwon, Ki-Rok

    2015-01-01

    Objectives: The aims of the study were to test the single-dose intravenous toxicity of Daebohwalryeok pharmacopuncture (DHRP) in Sprague-Dawley (SD) rats and to estimate the crude lethal dose. Methods: The experiments were conducted at Biotoxtech Co., a Good Laboratory Practice (GLP) laboratory, according to the GLP regulation and were approved by the Institutional Animal Care and Use Committee of Biotoxtech Co. (Approval no: 110156). The rats were divided into three groups: DHRP was injected into the rats in the two test groups at doses of 10 mL/kg and 20 mL/kg, respectively, and normal saline solution was injected into the rats in the control group. Single doses of DHRP were injected intravenously into 6 week old SD rats (5 male and 5 female rats per group). General symptoms were observed and weights were measured during the 14 day observation period after the injection. After the observation period, necropsies were done. Then, histopathological tests were performed. Weight data were analyzed with a one-way analysis of variance (ANOVA) by using statistical analysis system (SAS, version 9.2). Results: No deaths and no statistical significant weight changes were observed for either male or female SD rats in either the control or the test groups during the observation period. In addition, no treatment related general symptoms or necropsy abnormalities were observed. Histopathological results showed no DHRP related effects in the 20 mL/kg DHRP group for either male or female rats. Conclusion: Under the conditions of this study, the results from single-dose intravenous injections of DHRP showed that estimated lethal doses for both male and female rats were above 20 mL/kg. PMID:26120487

  18. Sequential morphologic analysis of the nephrotoxicity produced in rats by single doses of chlorozotocin.

    PubMed

    Dees, J H; Kramer, R A

    1986-01-01

    Chlorozotocin is a chloroethylnitrosourea antitumor agent that is in clinical trial for a variety of human tumors. Renal failure has been a reported side effect of treatment with several of the chloroethylnitrosoureas, including chlorozotocin. To better understand the pathogenesis of this target organ toxicity, we have studied the nephrotoxicity of a single high, intermediate, or low dose of chlorozotocin in male F344 rats. We report here the sequence of histopathologic changes seen over a 1-10-day (high dose) or 1-28-day (intermediate or low dose) period. The single high dose (40 mg/kg, s.c.) produced an acute cortical necrosis involving the proximal tubules, followed by later necrotic changes in the collecting ducts in the inner medulla. Karyomegaly was noted at 10 days in occasional cells of the papillary collecting ducts and urinary epithelium lining the papilla. A single intermediate dose (25 mg/kg, s.c.) caused a similar but less severe injury of later onset. Proximal tubule injury was less severe and more limited. Necrosis of papillary collecting ducts was not seen; however, karyomegaly was pronounced in cells of the collecting ducts in the inner stripe of the outer medulla and inner medulla, and in the urinary epithelium covering the papilla. No discernible histopathology was present following the low dose (12.5 mg/kg, s.c.) of chlorozotocin. The histopathology was correlated with biochemical parameters. Our findings have possible implications for monitoring the severity of nephrotoxic side effects in patients, as well as provide preliminary evidence that this antineoplastic agent may itself cause preneoplastic changes, a finding with important long term implications.

  19. A Flexible-Dose Study of Paliperidone ER in Patients With Nonacute Schizophrenia Previously Treated Unsuccessfully With Oral Olanzapine

    PubMed Central

    KOTLER, MOSHE; DILBAZ, NESRIN; ROSA, FERNANDA; PATERAKIS, PERIKLIS; MILANOVA, VIHRA; SMULEVICH, ANATOLY B.; LAHAYE, MARJOLEIN

    2016-01-01

    Objective: The goal of this study was to explore the tolerability, safety, and treatment response of switching from oral olanzapine to paliperidone extended release (ER). Methods: Adult patients with nonacute schizophrenia who had been treated unsuccessfully with oral olanzapine were switched to flexible doses of paliperidone ER (3 to 12 mg/d). The primary efficacy outcome was a ≥20% improvement in Positive and Negative Syndrome Scale (PANSS) total scores from baseline to endpoint for patients who switched medications because of lack of efficacy with olanzapine and noninferiority versus previous olanzapine treatment (mean endpoint change in PANSS total scores vs. baseline of ≤5 points) for patients who switched for reasons other than lack of efficacy. Safety and tolerability were assessed by monitoring adverse events, extrapyramidal symptoms, and weight change. Results: Of 396 patients, 65.2% were men, mean age was 40.0±12.0 years, and 75.5% had paranoid schizophrenia. Among the patients whose main reason for switching was lack of efficacy, an improvement in the PANSS total score of ≥20% occurred in 57.4% of patients. Noninferiority was confirmed for each subgroup of patients whose main reason for switching was something other than lack of efficacy. Paliperidone ER was generally well tolerated. Extrapyramidal symptoms as measured by total Extrapyramidal Symptom Rating Scale scores showed statistically significant and clinically relevant improvements at endpoint, the average weight decreased by 0.8±5.2 kg at endpoint, and a clinically relevant weight gain of ≥7% occurred in 8.0% of patients. Conclusion: Paliperidone ER flexibly-dosed over 6 months was well tolerated and associated with a meaningful clinical response in patients with nonacute schizophrenia who had previously been unsuccessfully treated with oral olanzapine. PMID:26813484

  20. Hepatic and intestine alterations in mice after prolonged exposure to low oral doses of Microcystin-LR.

    PubMed

    Sedan, Daniela; Laguens, Martín; Copparoni, Guido; Aranda, Jorge Oswaldo; Giannuzzi, Leda; Marra, Carlos Alberto; Andrinolo, Darío

    2015-09-15

    Oral intake of Microcystin-LR (MC-LR) is the principal route of exposure to this toxin, with prolonged exposure leading to liver damage of unspecific symptomatology. The aim of the present paper was therefore to investigate the liver and intestine damage generated by prolonged oral exposure to low MC-LR doses (50 and 100 μg MC-LR/kg body weight, administrated every 48 h during a month) in a murine model. We found alterations in TBARS, SOD activity and glutathione content in liver and intestine of mice exposed to both doses of MC-LR. Furthermore, the presence of MC-LR was detected in both organs. We also found hepatic steatosis (3.6 ± 0.6% and 15.3 ± 1.6%) and a decrease in intraepithelial lymphocytes (28.7 ± 5.0% and 44.2 ± 8.7%) in intestine of 50- and 100-μg MC-LR/kg treated animals, respectively. This result could have important implications for mucosal immunity, since intraepithelial lymphocytes are the principal effectors of this system. Our results indicate that prolonged oral exposure at 50 μg MC-LR/kg every 48 h generates significant damage not only in liver but also in intestine. This finding calls for a re-appraisal of the currently accepted NOAEL (No Observed Adverse Effect Level), 40 μg MC-LR/kg body weight, used to derive the guideline value for MC-LR in drinking water.

  1. A Randomized-Controlled Trial of Oral Low-Dose Isotretinoin for Difficult-To-Treat Papulopustular Rosacea.

    PubMed

    Sbidian, Emilie; Vicaut, Éric; Chidiack, Henri; Anselin, Elie; Cribier, Bernard; Dréno, Brigitte; Chosidow, Olivier

    2016-06-01

    Rosacea is a chronic inflammatory facial skin disease with psychosocial impact. Oral cyclines are recommended for moderate-to-severe papulopustular rosacea. Oral isotretinoin was found valuable for difficult-to-treat cases in several reports. This multicenter, double-blind, randomized-placebo-controlled trial compared oral isotretinoin (0.25 mg/kg/day) with placebo (2:1 ratio) for difficult-to-treat papulopustular rosacea. Included patients had at least eight papulopustular lesions. The primary endpoint after the 4-month treatment period was the response rate: at least 90% reduction of the number of papules/pustules compared with baseline. Secondary outcomes included measures on quality of life (Skindex score). Between February 2007 and August 2009, 156 patients were randomized to receive either isotretinoin (n = 108) or placebo (n = 48). In the intention-to-treat population, 57.4% of isotretinoin recipients reached the primary endpoint, compared with 10.4% of those taking the placebo (absolute difference, 47 percentage points; 95% confidence interval, 34.3-59.7; P < 0.0001). To consider therapy successful, 2.1 (95% confidence interval 1.7-2.9) patients had to be treated. Skindex scores had improved significantly more for isotretinoin- than placebo-treated patients. Rosacea relapsed in 27 (58.3%) of 51 patients who accepted 4 months of continued follow-up, with a median of 15 weeks to recurrence. The percentages of patients in each arm who stopped their treatment because of adverse event(s) did not differ. Low-dose isotretinoin was an effective therapeutic option for difficult-to-treat papulopustular rosacea. Further studies should investigate the value of a minimal effective isotretinoin dose to maintain these remissions. PMID:26854486

  2. Serum concentrations of methaqualone after repeated oral doses of a combination formulation to human subjects.

    PubMed

    White, C; Doyle, E; Chasseaud, L F; Taylor, T

    1976-09-30

    Concentrations of methaqualone have been measured in the serum of five male human subjects receiving five consecutive evening doses of a combination formulation containing methaqualone (250 mg), carbromal (300 mg) and benactyzine (0.33 mg) in each tablet. After administration of the first dose, mean peak serum concentrations of methaqualone (1.2 mug/ml) occurred at 3 h. After obtaining peak levels, mean concentrations of methaqualone declined rapidly during the next 6 h and thereafter more slowly during the next 18 h. After administration of the last (fifth) dose, mean peak serum concentrations of methaqualone (1.9 mug/ml; 1.5 mug/ml above the predose level) occurred at 2 h. After attaining peak levels, mean concentrations of methaqualone declined rapidly during the next 6 h, and thereafter more slowly, with a half-life of approximately 10 h. Mean concentrations of methaqualone in serum samples 24 h after the second, third, fourth or fifth doses were not significantly different (0.3 mug/ml - 0.6 mug/ml) during this period of dosing. This suggests that significant accumulation of methaqualone in the serum did not occur during a period of five consecutive evening doses of the combination formulation.

  3. Ingestion of chromium(VI) in drinking water by human volunteers: Absorption, distribution, and excretion of single and repeated doses

    SciTech Connect

    Kerger, B.D.; Corbett, G.E.; Dodge, D.G.

    1997-01-01

    This study examines the magnitude of hexavalent chromium [Cr(VI)] absorption, distribution, and excretion following oral exposure to 5 and 10 mg Cr(VI)/L in drinking water administered as a single bolus dose or for 3 d at a dosage of 1 L/d. Adult male volunteers were used. In the bolus dose studies, a fairly consistent pattern of urinary chromium excretion was observed, with an average half life of about 39 h. However, 4-d total urinary chromium excretion and peak concentrations in urine and blood varied considerably among the 5 volunteers. Studies of repeated exposure to small volumes ingested at a more gradual rate showed similar urinary chromium excretion patterns but generally lower chromium uptake/excretion. These data suggest that virtually all of the ingested Cr(VI) at 5 and 10 mg Cr(VI)/L was reduced to Cr(III) before entering the bloodstream. The interindividual differences in total chromium uptake and excretion are plausibly explained by ingestion of appreciable doses on an empty stomach, likely results in the formation of well-absorbed Cr(III) organic complexes. No clinical indications of toxicity in the volunteers and the patterns of blood uptake and urinary excretion of chromium are consistent with a predominant uptake of Cr(III) organic complexes that are excreted more slowly than inorganic forms of Cr(III). Therefore, it appears that the endogenous reducing agents within the upper gastrointestinal tract and the blood provide sufficient reducing potential to prevent any substantial systemic uptake of Cr(VI) following drinking-water exposures at 5-10 mg Cr(VI)/L. Based on these data, the chemical environment in the gastrointestinal tract and the blood is effective even under relative fasting condition in reducing Cr(VI) to one or more forms of Cr(III). 54 refs., 5 figs., 1 tab.

  4. Implication of Enterohepatic Re-Circulation on Single Dose Bioequivalence Evaluation of Two Brands of Clonidine Hydrochloride Tablets in Healthy Human Volunteers

    PubMed Central

    Mehta, H. R.; Patel, I. K.; Patel, N. H.; Patel, D. M.; Parmar, A. B.

    2009-01-01

    A single dose, crossover bioequivalence study of two different brands of clonidine hydrochloride 25 μg tablets was conducted in 24 (+2 stand by) healthy, adult, male, Indian subjects under fasting conditions to check the implication of enterohepatic re-circulation on assessment of bioequivalence. After an overnight fasting of at least 10 h, the subjects received single oral dose of test or reference product with either of the product as per randomization schedule in each period with a washout period of 10 days. The pre-dose blood sample was collected within a period of one h before dosing. The post-dose blood samples were collected at specified time intervals up to 96 h. The plasma concentrations of clonidine were quantified by validated LCMS/MS method and pharmacokinetic parameters were computed. The 90% confidence intervals of test/reference ratios for Cmax and area under the plasma-concentration- time-curve AUC under 0-t were found to be between 0.80 and 1.25 for log-transformed data. Analysis of variance did not show significant difference to these parameters. No meaningful values of Kel and therefore AUC under 0-infinity could be calculated for significant number of subjects due to enterohepatic re-circulation. Based on the results obtained, two different brands of clonidine 25 μg tablets have comparable rate and extent of absorption after oral administration but failed to show bioequivalence as per regulatory requirement of Food and Drugs Administration-united states. PMID:20502569

  5. Dietary pretreatment with green tea polyphenol, (-)-epigallocatechin-3-gallate reduces the bioavailability and hepatotoxicity of subsequent oral bolus doses of (-)-epigallocatechin-3-gallate.

    PubMed

    James, Karma D; Forester, Sarah C; Lambert, Joshua D

    2015-02-01

    Human case-studies have reported an association between green tea-based dietary supplements and hepatotoxicity. Studies have demonstrated the hepatotoxicity of high-dose oral bolus dosing with the tea polyphenol (-)-epigallocatechin-3-gallate (EGCG) in mice and dogs. We examined the effect of pretreatment with dietary EGCG on the hepatotoxicity and bioavailability of acute oral bolus dosing with EGCG in CF-1 mice. EGCG (750 mg/kg, i.g., once daily for 3 days) increased plasma alanine aminotransferase by 80-fold, decreased both reduced (by 59%) and total (by 33%) hepatic glutathione, and increased hepatic levels of phosphorylated histone 2AX. Pretreatment with dietary EGCG (3.2 mg/g diet) for 2 weeks mitigated hepatotoxicity. Acute oral EGCG also decreased mRNA expression of glutathione reductase. Dietary pretreatment prevented these decreased and increased glutathione peroxidase (Gpx)2, Gpx3, Gpx5, and Gpx7 expression. We found that dietary EGCG reduced the plasma (57% reduction) and hepatic (71% reduction) EGCG exposure following oral bolus dosing compared to mice that were not pre-treated. Overall, it appears that EGCG can modulate its own bioavailability and that dietary treatment may reduce the toxic potential of acute high oral bolus doses of EGCG. These data may partly explain the observed variation in hepatotoxic response to green tea-containing dietary supplements.

  6. Evaluation of safety and pharmacokinetics of sodium 2,2 dimethylbutyrate, a novel short chain fatty acid derivative, in a phase 1, double-blind, placebo-controlled, single-dose, and repeat-dose studies in healthy volunteers.

    PubMed

    Perrine, Susan P; Wargin, William A; Boosalis, Michael S; Wallis, Wayne J; Case, Sally; Keefer, Jeffrey R; Faller, Douglas V; Welch, William C; Berenson, Ronald J

    2011-08-01

    Pharmacologic induction of fetal globin synthesis is an accepted therapeutic strategy for treatment of the beta hemoglobinopathies and thalassemias, as even small increases in hemoglobin F (HbF) levels reduce clinical severity in sickle cell disease (SCD) and reduce anemia in beta thalassemia. Prior generation short chain fatty acid therapeutics, arginine butyrate (AB), and phenylbutyrate, increased fetal and total hemoglobin levels in patients, but were limited by high doses or intravenous (IV) infusion. A fetal globin-inducing therapeutic with convenient oral dosing would be an advance for these classic molecular diseases. Healthy adult human subjects were treated with a novel short chain fatty acids (SCFA) derivative, sodium 2,2 dimethylbutyrate (SDMB), or placebo, with 1 of 4 single dose levels (2, 5, 10, and 20 mg/kg) or daily doses (5, 10, or 15 mg/kg) over 14 days, and monitored for adverse clinical and laboratory events, drug levels, reticulocytes, and HbF assays. SDMB was well-tolerated with no clinically significant adverse events related to study medication. The terminal half-life ranged from 9 to 15 hours. Increases in mean absolute reticulocytes were observed at all dose levels in the 14-day study. The favorable pharmacokinetics (PK) profiles and safety findings indicate that SDMB warrants further investigation for treatment of anemic subjects with beta hemoglobinopathies.

  7. [Toxicokinetics of bakuchiol, hepatic and renal toxicity in rats after single oral administration of Psoraleae Fructus and combination with Glycyrrhizae Radix et Rhizoma].

    PubMed

    Zhao, Zi-jing; Gong, Zheng; Shi, Shao-ze; Yang, Jin-lan; Ma, Na-na; Wang, Qi

    2015-06-01

    To study the toxicokinetics of bakuchiol, hepatic and renal toxicity in rats after single oral administration of Psoraleae Fructus and combined with Glycyrrhizae Radix et Rhizoma, in order to provide scientific evidences for clinical safe medication use. A total of 35 SD rats were randomly divided into seven groups: vehicle (distilled water) control group, Glycyrrhizae Radix et Rhizoma group, positive control (aristolochic acid A) group, Psoraleae Fructus (40 g x kg(-1)) group( both male and female rats), Psoraleae Fructus and Glycyrrhizae Radix et Rhizoma (40 +20) g x kg(-1) group (both male and female rats). HPLC-UV method was used to determine the concentration of bakuchiol in rat plasma at different time points after single oral administration. Plasma alanine transaminase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), plasma creatinine (Cr), N-acetyl-β-D-glucosaminidase (NAG) and kidney injury molecule 1 (Kim-1) were measured after administration for 24 h. The main toxicokinetics parameters of bakuchiol in rats exert significantly gender difference. When Psoraleae Fructus combination with Glycyrrhizae Radix et Rhizoma, the total area under the plasma concentration-time curve( AUC), C(max), and plasma clearance (CL) of bakuchiol were increased, respectively; CL, half-life (t½) were decreased, and T(max) were prolonged. The biochemical indicators (including ALT, AST, BUN, Cr and KIM-1 level) in different dose of Psoraleae Fructus groups, were found no statistically significant difference when compared with vehicle control group. The level of NAG in both Psoraleae Fructus and compatibility with Glycyrrhizae Radix et Rhizoma groups were significant increased (P < 0.05). There are obvious effects on toxicokinetics of bakuchiol in rats when Psoraleae Fructus combined with Glycyrrhizae Radix et Rhizoma. Renal toxicity induced by Psoraleae Fructus at high dose was observed after single oral administration and no liver damage in rats was found.

  8. Safety and Efficacy of Single Dose versus Multiple Doses of AmBisome® for Treatment of Visceral Leishmaniasis in Eastern Africa: A Randomised Trial

    PubMed Central

    Khalil, Eltahir A. G.; Weldegebreal, Teklu; Younis, Brima M.; Omollo, Raymond; Musa, Ahmed M.; Hailu, Workagegnehu; Abuzaid, Abuzaid A.; Dorlo, Thomas P. C.; Hurissa, Zewdu; Yifru, Sisay; Haleke, William; Smith, Peter G.; Ellis, Sally; Balasegaram, Manica; EL-Hassan, Ahmed M.; Schoone, Gerard J.; Wasunna, Monique; Kimutai, Robert; Edwards, Tansy; Hailu, Asrat

    2014-01-01

    Background Anti-leishmanial drug regimens that include a single dose AmBisome® could be suitable for eastern African patients with symptomatic visceral leishmaniasis (VL) but the appropriate single dose is unknown. Methodology A multi-centre, open-label, non-inferiority, randomized controlled trial with an adaptive design, was conducted to compare the efficacy and safety of a single dose and multiple doses of AmBisome® for the treatment of VL in eastern Africa. The primary efficacy endpoint was definitive cure (DC) at 6 months. Symptomatic patients with parasitologically-confirmed, non-severe VL, received a single dose of AmBisome® 7.5 mg/kg body weight or multiple doses, 7 times 3 mg/kg on days 1–5, 14, and 21. If interim analyses, evaluated 30 days after the start of treatment following 40 or 80 patients, showed the single dose gave significantly poorer parasite clearance than multiple doses at the 5% significance level, the single dose was increased by 2·5 mg/kg. In a sub-set of patients, parasite clearance was measured by quantitative reverse transcriptase (qRT) PCR. Principal Findings The trial was terminated after the third interim analysis because of low efficacy of both regimens. Based on the intention-to-treat population, DC was 85% (95%CI 73–93%), 40% (95%CI 19–64%), and 58% (95%CI 41–73%) in patients treated with multiple doses (n = 63), and single doses of 7·5 (n = 21) or 10 mg/kg (n = 40), respectively. qRT-PCR suggested superior parasite clearance with multiple doses as early as day 3. Safety data accorded with the drug label. Conclusions The tested AmBisome® regimens would not be suitable for VL treatment across eastern Africa. An optimal single dose regimen was not identified. Trials Registration www.clinicaltrials.gov NCT00832208 PMID:24454970

  9. The pharmacokinetic profile of crocetin in healthy adult human volunteers after a single oral administration.

    PubMed

    Umigai, N; Murakami, K; Ulit, M V; Antonio, L S; Shirotori, M; Morikawa, H; Nakano, T

    2011-05-15

    Crocetin, a unique carotenoid with a short carbon chain length, is an active compound of saffron and Gardenia jasminoides Ellis used as traditional herbal medicine. The present study was undertaken to investigate the pharmacokinetic profiles of crocetin in healthy adult subjects. The study was conducted as an open-label, single dose escalation with 10 Filipino volunteers (5 men and 5 women). The subjects received a single dose of crocetin at three doses (7.5, 15 and 22.5 mg) in one week interval. Blood samples were collected from the brachial vein before and at 1, 2, 4, 6, 8, 10 and 24 h after administration. Plasma concentrations of crocetin were determined by high-performance liquid chromatography (HPLC). Crocetin was rapidly absorbed and detected within an hour of administration with a mean time to reach maximum concentration (T(max)) of crocetin ranging from 4.0 to 4.8 h. The mean values of C(max) and AUC(0-24h) ranged from 100.9 to 279.7 ng/ml and 556.5 to 1720.8 ng. h/ml respectively. C(max) and AUC values increased with dose proportional manner. Crocetin was eliminated from human plasma with a mean elimination half life (T(½) of 6.1 to 7.5 h. In summary, there were no serious adverse events up to 22.5 mg dose of crocetin while crocetin was found to be absorbed more quickly than the other carotenoids such as β-carotene, lutein and lycopene. PMID:21112749

  10. Lead poisoning in cattle: reassessment of the minimum toxic oral dose

    SciTech Connect

    Zmudski, J.; Bratton, G.R.; Womac, C.; Rowe, L.

    1983-04-01

    After feeding male Holstein calves Pb acetate by nurse bottle it was found that daily Pb intakes of 2.7 mg Pb/kg can kill calves on milk diets in 20 days or less while 5.0 mg Pb/kg/day consistently caused signs of intoxication and death in 7 days. Absorption rate of Pb was rapid and tissue depositions were high in calves on milk replacer diet. Tissues were analyzed by atomic absorption spectrophotometry. Data suggest that diet, dosing method, and dosing time must be carefully considered in evaluations of minimum toxic dose. The consistent production of seizures at these low daily Pb intakes suggests that this calf model may be valuable in the study of Pb encephalopathy. (JMT)

  11. Single high dose intraoperative electrons for advanced stage pancreatic cancer: Phase I pilot study

    SciTech Connect

    Goldson, A.L.; Ashaveri, E.; Espinoza, M.C.

    1981-07-01

    Phase I toxicity studies with intraoperative radiotherapy proved to be a feasible adjunct to surgery for unresectable malignancies of the pancreas at Howard University Hospital. There have been minimal side effects or complications related to the combination of limited surgical decompression and intraoperative radiotherapy alone. The toxic effects of intraoperative radiotherapy on normal tissues is being assessed on a dose volume basis. Doses of 2000 to 2500 rad in a single exposure to include the pancreas, regional nodes and duodenum are acceptable if the total treatment volume is less than or equal to 100 cm. The tumoricidal effects on the cancer are demonstratable when one reviews the pathological specimens that illustrate massive tumor necrosis and fibros replacement, but in all cases reviewed, viable cancer was noted. Intraoperative radiotherapy, therefore, represents a significant boost dose for resectable, partially resectable or non-resectable tumors when added to conventional external beam irradiation and/or chemotherapy. Preliminary clinical data and minimal toxicity justifies further investigation.

  12. Analysis of micronuclei and DNA single-strand breaks in mouse splenocytes and peripheral lymphocytes after oral administration of tetramethylthiuram disulfide (thiram).

    PubMed

    Villani, P; Andreoli, C; Crebelli, R; Pacchierotti, F; Zijno, A; Carere, A

    1998-03-01

    The fungicide thiram (tetramethylthiuram disulfide, TMTD) was administered by repeated oral intubations to groups of male B6C3F1 mice at 100, 300 and 900 mg/kg body weight for 4 consecutive days, or at 300 mg/kg for 8 and 12 days. 24 hr after the last treatment animals were killed, and splenocyte cultures were set up for the analysis of micronuclei by the cytokinesis-block method. DNA single strand breaks (ssb) and alkali labile sites were also analysed by the single cell gel electrophoresis (Comet) assay in splenocytes and lymphocytes of animals receiving the 8- and 12-day treatments. Parallel experiments with human peripheral lymphocytes were carried out to assess the ability of thiram to induce micronuclei and DNA ssb and alkaline labile sites under in vitro conditions. No significant increase of micronucleated splenocytes was observed in treated animals, despite some evidence of treatment-related cellular toxicity. A borderline excess of DNA damage was suggested by the Comet assay on circulating lymphocytes, whereas negative results were obtained with splenocytes. In vitro, positive results with both genetic end points were obtained in assays with human lymphocytes in the dose ranges 0.5-24 microg/ml and 0.1-8 microg/ml for micronucleus and Comet assays, respectively. These results suggest that thiram, despite its established genotoxicity in vitro, is devoid of appreciable clastogenic and/or aneugenic activity in vivo after oral administration to mice at the maximum tolerated dose.

  13. Blood mineral, hormone, and osteocalcin responses of multiparous Jersey cows to an oral dose of 25-hydroxyvitamin D3 or vitamin D3 before parturition.

    PubMed

    Taylor, M S; Knowlton, K F; McGilliard, M L; Seymour, W M; Herbein, J H

    2008-06-01

    Twenty-seven multiparous Jersey cows were randomly assigned to receive an oral bolus containing corn starch (control, CON), corn starch plus 15 mg of 25-hydroxyvitamin D(3) (25-OH), or 15 mg of cholecalciferol (D(3)) at 6 d before expected parturition. Cows were maintained in individual box stalls from 20 d before expected parturition and fed a common diet. Jugular blood samples were collected at -14, -13, -5, -4, -3, -2, -1 d before expected calving, at calving, and at 1, 3, 5, 7, 9, 11, 13, 28, 56, and 84 d postcalving. After calving, cows were housed in 1 pen in a free-stall barn and consumed a common diet. Colorimetric assays were used to analyze Ca, P, and Mg concentrations in serum. Serum concentrations of osteocalcin (OC), an indicator of bone formation, serum 25-hydroxyvitamin D(3), and parathyroid hormone (PTH) were determined in samples obtained from d -5 through d 13. The 9 control multiparous cows and 5 untreated primiparous cows were used to evaluate the effect of parity on the variables that were measured. There was no effect of parity on Ca, PTH, or 25-OH concentration. Compared with second-lactation cows and older cows (>2 lactations), first-lactation cows had greater serum OC (22.3, 32.0, and 48.3 ng/mL, respectively), indicating that younger animals were forming more bone. Blood Ca, P, and Mg decreased near the time of calving and then increased over time. Serum 25-hydroxyvitamin D(3) was greater for cows dosed with 25-OH (119.0 ng/mL) compared with those dosed with D(3) (77.5 ng/mL) or CON (69.3 ng/mL). Cows dosed with 25-OH tended to have lower serum PTH concentration, but treatments did not affect serum Ca, P, or Mg. Serum OC was greater in second-lactation cows compared with cows entering their third or fourth lactation but OC was unaffected by treatment. Although results indicated a 60% increase in serum 25-hydroxyvitamin D(3) due to a single oral dose of 25-OH before calving, the amount administered in this study apparently was not

  14. Single-dose Intramuscular Injection Toxicology of Danggui Pharmacopuncture (DGP) in Sprague-Dawley Rats

    PubMed Central

    Sun, SeungHo; Jeong, JongJin; Park, Sunju; Lee, KwangHo; Yu, JunSang; Seo, Hyung-Sik; Kwon, KiRok

    2015-01-01

    Objectives: The purpose of the study is to assess both the approximate lethal dose and the single dose intramuscular injection toxicity of Danggui (Angelica gigantis radix) pharmacopuncture (DGP) in Sprague-Dawley (SD) rats. Methods: The experiments were conducted at the good laboratory practice (GLP) laboratory, Biotoxtech Co., which is a laboratory approved by the ministry of food and drug safety (MFDS). The study was performed according to the GLP regulation and the toxicity test guidelines of the MFDS (2009) after approval of the institutional animal care and use committee of Biotoxtech. Single doses of DGP were injected intramuscularly into the rats in three test groups of 6 week old SD rats (5 male and 5 female rats per groups) in the amounts of 0.1, 0.5, and 1.0 mL/animal for groups 2, 3, and 4, respectively, and normal saline solution in the amount of 1.0 mL/animal was injected intramuscularly into the rats (5 male and 5 female rats) in the control group. Observations of the general symptoms and weight measurements were performed during the 14 day observation period after the injection. Hematologic and serum biochemical examination, necropsy, and a local tolerance test at the injection site were done after the observation period. Results: No death was observed in three test groups (0.1, 0.5 and 1.0 mL/animal group). In addition, the injection of DGP had no effect on general symptoms, weights, hematologic and serum biochemical examination, and necropsy. The results from the local tolerance tests at injection site showed no treatment related effects in the SD rats. Conclusion: The results of single dose intramuscular injection of DGP suggest that the approximate lethal dose is above 1.0 mL/animal for both male and female SD rats and that intramuscular injection of DGP may be safe. PMID:25830059

  15. Single-dose monomeric HA subunit vaccine generates full protection from influenza challenge

    PubMed Central

    Mallajosyula, Jyothi K; Hiatt, Ernie; Hume, Steve; Johnson, Ashley; Jeevan, Trushar; Chikwamba, Rachel; Pogue, Gregory P; Bratcher, Barry; Haydon, Hugh; Webby, Richard J; McCormick, Alison A

    2014-01-01

    Recombinant subunit vaccines are an efficient strategy to meet the demands of a possible influenza pandemic, because of rapid and scalable production. However, vaccines made from recombinant hemagglutinin (HA) subunit protein are often of low potency, requiring high dose or boosting to generate a sustained immune response. We have improved the immunogenicity of a plant-made HA vaccine by chemical conjugation to the surface of the Tobacco mosaic virus (TMV) which is non infectious in mammals. We have previously shown that TMV is taken up by mammalian dendritic cells and is a highly effective antigen carrier. In this work, we tested several TMV-HA conjugation chemistries, and compared immunogenicity in mice as measured by anti-HA IgG titers and hemagglutination inhibition (HAI). Importantly, pre-existing immunity to TMV did not reduce initial or boosted titers. Further optimization included dosing with and without alum or oil-in water adjuvants. Surprisingly, we were able to stimulate potent immunogenicity and HAI titers with a single 15µg dose of HA as a TMV conjugate. We then evaluated the efficacy of the TMV-HA vaccine in a lethal virus challenge in mice. Our results show that a single dose of the TMV-HA conjugate vaccine is sufficient to generate 50% survival, or 100% survival with adjuvant, compared with 10% survival after vaccination with a commercially available H1N1 vaccine. TMV-HA is an effective dose-sparing influenza vaccine, using a single-step process to rapidly generate large quantities of highly effective flu vaccine from an otherwise low potency HA subunit protein. PMID:24378714

  16. Single-dose monomeric HA subunit vaccine generates full protection from influenza challenge.

    PubMed

    Mallajosyula, Jyothi K; Hiatt, Ernie; Hume, Steve; Johnson, Ashley; Jeevan, Trushar; Chikwamba, Rachel; Pogue, Gregory P; Bratcher, Barry; Haydon, Hugh; Webby, Richard J; McCormick, Alison A

    2014-01-01

    Recombinant subunit vaccines are an efficient strategy to meet the demands of a possible influenza pandemic, because of rapid and scalable production. However, vaccines made from recombinant hemagglutinin (HA) subunit protein are often of low potency, requiring high dose or boosting to generate a sustained immune response. We have improved the immunogenicity of a plant-made HA vaccine by chemical conjugation to the surface of the Tobacco mosaic virus (TMV) which is non infectious in mammals. We have previously shown that TMV is taken up by mammalian dendritic cells and is a highly effective antigen carrier. In this work, we tested several TMV-HA conjugation chemistries, and compared immunogenicity in mice as measured by anti-HA IgG titers and hemagglutination inhibition (HAI). Importantly, pre-existing immunity to TMV did not reduce initial or boosted titers. Further optimization included dosing with and without alum or oil-in water adjuvants. Surprisingly, we were able to stimulate potent immunogenicity and HAI titers with a single 15 µg dose of HA as a TMV conjugate. We then evaluated the efficacy of the TMV-HA vaccine in a lethal virus challenge in mice. Our results show that a single dose of the TMV-HA conjugate vaccine is sufficient to generate 50% survival, or 100% survival with adjuvant, compared with 10% survival after vaccination with a commercially available H1N1 vaccine. TMV-HA is an effective dose-sparing influenza vaccine, using a single-step process to rapidly generate large quantities of highly effective flu vaccine from an otherwise low potency HA subunit protein. PMID:24378714

  17. Combined oral corticosteroid-methotrexate therapy in Eales' disease.

    PubMed

    Saxena, Sandeep

    2009-01-01

    The efficacy of combined oral corticosteroid and low-dose oral methotrexate pulsed therapy in Eales' disease was evaluated prospectively, based on weighted visual morbidity scale for disease activity and visual acuity grading in 36 consecutive cases. Oral corticosteroids in a weekly tapering dose for 4 weeks and 12.5 mg methotrexate as a single oral dose, once per week for 12 weeks, were administered simultaneously. We concluded that this combined oral therapy is clinically effective with an acceptable safety profile. PMID:19845224

  18. A retrospective analysis of allergic reaction severities and minimal eliciting doses for peanut, milk, egg, and soy oral food challenges.

    PubMed

    Zhu, Jianmei; Pouillot, Régis; Kwegyir-Afful, Ernest K; Luccioli, Stefano; Gendel, Steven M

    2015-06-01

    Food allergy is a public health concern, affecting up to 6% of children and 2% of adults. The severity of allergic reactions can range from mild to potentially life-threatening. In addition, the minimum amount of protein needed to provoke an allergic reaction in an individual patient (the minimal eliciting dose (MED)) ranges from a few micrograms to several grams. To determine whether a retrospective analysis of published data from oral food challenges could be used to assess the potential relationship between MEDs and reaction severities at the MEDs, a three class (mild, moderate, severe) reaction grading system was developed by integrating previously published reaction grading systems. MEDs and symptoms were collected from food challenge studies and each reaction was graded using the integrated grading system. Peanut allergic patients who experienced severe reactions had significantly higher MEDs and threshold distribution doses than those who experienced mild and moderate reactions. No significant differences in threshold distributions according to the severity grading were found for milk, egg and soy. The relationship between threshold dose distribution and reaction severity based on these grading criteria differed between peanut and other allergens, and severe reactions were found to occur in some patients at low MEDs for all of these food allergens.

  19. Repeated dose 28-days oral toxicity study of Carica papaya L. leaf extract in Sprague Dawley rats.

    PubMed

    Afzan, Adlin; Abdullah, Noor Rain; Halim, Siti Zaleha; Rashid, Badrul Amini; Semail, Raja Hazlini Raja; Abdullah, Noordini; Jantan, Ibrahim; Muhammad, Hussin; Ismail, Zakiah

    2012-04-10

    Carica papaya L. leaves have been used in ethnomedicine for the treatment of fevers and cancers. Despite its benefits, very few studies on their potential toxicity have been described. The aim of the present study was to characterize the chemical composition of the leaf extract from 'Sekaki' C. papaya cultivar by UPLC-TripleTOF-ESI-MS and to investigate the sub-acute oral toxicity in Sprague Dawley rats at doses of 0.01, 0.14 and 2 g/kg by examining the general behavior, clinical signs, hematological parameters, serum biochemistry and histopathology changes. A total of twelve compounds consisting of one piperidine alkaloid, two organic acids, six malic acid derivatives, and four flavonol glycosides were characterized or tentatively identified in the C. papaya leaf extract. In the sub-acute study, the C. papaya extract did not cause mortality nor were treatment-related changes in body weight, food intake, water level, and hematological parameters observed between treatment and control groups. Some biochemical parameters such as the total protein, HDL-cholesterol, AST, ALT and ALP were elevated in a non-dose dependent manner. Histopathological examination of all organs including liver did not reveal morphological alteration. Other parameters showed non-significant differences between treatment and control groups. The present results suggest that C. papaya leaf extract at a dose up to fourteen times the levels employed in practical use in traditional medicine in Malaysia could be considered safe as a medicinal agent.

  20. Oral Reference Dose for ethylene glycol based on oxalate crystal-induced renal tubule degeneration as the critical effect

    SciTech Connect

    Snellings, William M.; Corley, Richard A.; McMartin, K. E.; Kirman, Christopher R.; Bobst, Sol M.

    2013-03-31

    Several risk assessments have been conducted for ethylene glycol (EG). These assessments identified the kidney as the primary target organ for chronic effects. None of these assessments have incorporated the robust database of species-specific toxicokinetic and toxicodynamic studies with EG and its metabolites in defining uncertainty factors used in reference value derivation. Pertinent in vitro and in vivo studies related to one of these metabolites, calcium oxalate, and its role in crystal-induced nephropathy are summarized, and the weight of evidence to establish the mode of action for renal toxicity is reviewed. Previous risk assessments were based on chronic rat studies using a strain of rat that was later determined to be less sensitive to the toxic effects of EG. A recently published 12-month rat study using the more sensitive strain (Wistar) was selected to determine the point of departure for a new risk assessment. This approach incorporated toxicokinetic and toxicodynamic data and used Benchmark Dose methods to calculate a Human Equivalent Dose. Uncertainty factors were chosen, depending on the quality of the studies available, the extent of the database, and scientific judgment. The Reference Dose for long-term repeat oral exposure to EG was determined to be 15 mg/kg bw/d.

  1. A therapeutic response to a single diagnostic dose of luteinising hormone-releasing hormone.

    PubMed

    Distiller, L A; Sagel, J; Polakow, E S; Morley, J E

    1975-01-11

    Luteinising hormone-releasing hormone (LH-RH) administration is a useful provocative test for the evaluation of the hypothalamic-pituitary-gonadal axis. Seven cases with oligomenorrhoea or amenorrhoea are reported, in which a single diagnostic injection of LH-RH produced an apparent therapeutic response. Six patients converted to a regular normal menstrual cycle, and 4 of these had evidence of ovulation. The seventh patient conceived. It is postulated that in some cases of hypothalamic menstrual dysfunction the gonadotrophic imbalance may be corrected by a single intravenous dose of LH-RH.

  2. Lack of protective effect of thromboxane synthetase inhibitor (CGS-13080) on single dose radiated canine intestine

    SciTech Connect

    Barter, J.F.; Marlow, D.; Kamath, R.K.; Harbert, J.; Torrisi, J.R.; Barnes, W.A.; Potkul, R.K.; Newsome, J.T.; Delgado, G. )

    1991-03-01

    The effect of a thromboxane A2 synthetase inhibitor (CGS-13080) on canine intestine was studied using a single dose of radiation, and radioactive microspheres were used to determine resultant blood flow. Thromboxane A2 causes vasospasm and platelet aggregation and may play a dominant role in radiation injury. However, there was no effect on the intestinal blood flow diminution occurring after radiation in this laboratory model using this thromboxane A2 synthetase inhibitor.

  3. A clinical pharmacokinetic study comparing two azelastine hydrochloride nasal formulations in a single-dose design.

    PubMed

    Du, Daniel; Targett, Darren; Stolberg, Erhard; Canali, Alessandra

    2014-03-01

    Azelastine hydrochloride is a potent second-generation antihistamine, available in Europe and the USA as a nasal spray formulation for the treatment of allergic rhinitis symptoms. GlaxoSmithKline (GSK) Consumer Healthcare has developed a new nasal formulation of azelastine hydrochloride. The present study was aimed at comparing the clinical pharmacokinetic profiles and assessing the bioequivalence of the new formulation of azelastine hydrochloride with a marketed reference nasal spray product. This was a randomized, two-way crossover, two-stage, single-dose pharmacokinetic study with 2 weeks washout between the two treatment periods. A dosage of 0.28 mg of the test and reference products was administered as a single dose to healthy volunteers according to the crossover design. Twenty-three subjects (15 subjects from stage 1 and 8 subjects from stage 2) were enrolled in the study. Adjusted mean values for AUC0-t were 1,526.8 h pg/mL for the test drug and 1,441.5 h pg/mL for the reference drug; for C max the values were 61.59 pg/mL for the test drug and 58.21 pg/mL for the reference drug. The 94.12 % CI of geometric mean ratios (test/reference) were 0.99-1.13 and 0.95-1.18 for AUC0-t and C max. This met the predefined criteria for bioequivalence between test and reference drugs. Secondary pharmacokinetic parameters for azelastine and for the metabolite desmethyl azelastine, AUC(0-∞) and t max, were numerically similar between the two study treatments. Both test and reference azelastine hydrochloride formulations were well tolerated at single dose. This study demonstrated the bioequivalence between the new azelastine hydrochloride nasal spray formulation and the marketed reference Allergodil(®) after single-dose administration. PMID:23681835

  4. Induction of lymphoma and osteosarcoma in mice by single and protracted low alpha doses

    SciTech Connect

    Mueller, W.A.L.; Luz, A.; Murray, A.B.; Linzner, U. )

    1990-09-01

    Internal doses from the short-lived alpha-emitter 22Ra were given to 4-wk-old female mice. One group of about 300 animals received a single injection of 18.5 kBq 22Ra kg-1 body weight, corresponding to a mean skeletal alpha dose of 0.15 Gy. A second group of about 300 animals received the same total amount of 224Ra in the form of 72 fractions of 257 Bq kg-1 each, applied twice weekly during 36 wk. The fractionated group received the same final mean total skeletal dose of 0.15 Gy as the single injected group, but with a mean skeletal dose rate of 1 mGy d-1. A rather high incidence, 13.5% (40/296), of early malignant lymphomas was observed in the fractionated group during and shortly after the injection period, followed by a 7% incidence (21/296) of osteosarcomas during the second half of the animals' lifetime. The group with a single injection did not develop early lymphomas but did develop osteosarcomas later with an incidence of 5.8% (17/295). The occurrence of osteosarcomas was similar up to day 800 in the two experimental groups. Surprisingly, however, after this period no additional case of osteosarcoma was observed in the single-injected group, whereas one-third of all osteosarcomas occurred after day 800 in the protracted group. The additional later occurrence of osteosarcomas occurred after indicates a longer lasting induction effect on osteosarcomas, or a promoting effect in older age, for this kind of treatment.

  5. 40 CFR 799.9305 - TSCA Repeated dose 28-day oral toxicity study in rodents.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... dose level. If interim sacrifices are planned, the number should be increased by the number of animals.... Measurements of food consumption should be made at least weekly. If the test substance is administered via the... requirements of the Toxic Substances Control Act (TSCA) (15 U.S.C.......

  6. Repeated dose oral toxicity of Trivanga Bhasma in Swiss albino mice

    PubMed Central

    Jamadagni, Pallavi S.; Jamadagni, Shrirang B.; Singh, Rajendrakumar; Gaidhani, Sudesh N.; Upadhyay, Sachchidanand; Hazra, Jayram

    2013-01-01

    Trivanga Bhasma, a metallic preparation containing Bhasmas of Naga (lead), Vanga (tin) and Yashada (zinc), was studied for repeated dose toxicity in Swiss albino mice to estimate No Observed Effect Level (NOEL) or No Observed Adverse Effect Level (NOAEL). A total of 80 Swiss albino mice of either sex with an average body weight of 28-30 g were equally divided into four groups (Group I, II, III, and IV). Group I served as control and was given vehicle (honey: water in 2:3 ratio) Group II, III, and IV received Trivanga Bhasma @ 7.8, 39.5,and 78 mg/kg body weight for 90 consecutive days. The effect of drug was assessed on body weight, feed and water consumption changes, hematological, and histopathological parameters. At the end of the study, all animals were sacrificed and examined for gross pathological changes. Histopathological evaluation was performed for control and high dose group. Trivanga Bhasma was found to be safe. No significant clinical signs were noted in all groups studied. No major alterations were observed during histopathological evaluation. Hence, dose rate of 78 mg/kg body weight was established as NOAEL. It is suggested to carry out a toxicity study at possible higher doses and in a different species so as to establish target organ of toxicity. PMID:24049417

  7. Ethyl glucuronide concentrations in oral fluid, blood, and urine after volunteers drank 0.5 and 1.0 g/kg doses of ethanol.

    PubMed

    Høiseth, Gudrun; Yttredal, Borghild; Karinen, Ritva; Gjerde, Hallvard; Mørland, Jørg; Christophersen, Asbjørg

    2010-01-01

    The aim of this study was to investigate the concentrations of ethyl glucuronide (EtG) in oral fluid, blood, and urine after healthy volunteers drank two doses of ethanol, 0.5 (n = 11) and 1.0 g/kg (n = 10), after an overnight fast. Samples of oral fluid, blood, and urine were collected before drinking started and at 1.5, 3.5, 5.5, 8.5, 11.5, and 24 h post-dosing. Following ingestion of low dose of ethanol, the Cmax for EtG was 0.36 mg/L (range 0.28-0.41 mg/L) in blood and 69.8 mg/L (range 47.1-96.5 mg/L) in urine. In oral fluid, the concentrations were < 1% of those in blood, and only three subjects exceeded the limit of quantification for EtG in oral fluid. After ingestion of the high dose of ethanol, the Cmax for EtG was 1.06 mg/L (range 0.8-1.22 mg/L) in blood, 159.9 mg/L (range 97.2-225.5 mg/L) in urine, and 0.032 mg/L (range 0.013-0.059 mg/L) in oral fluid. The median oral fluid/blood ratio was 0.029 (range 0.012-0.054) for EtG. The detection time for EtG was median 11.5 h (range 3.5-11.5 h) in oral fluid. According to this, the detection time for EtG in oral fluid is therefore only a few hours longer than for ethanol itself and represents limited additional value. PMID:20663284

  8. Serum methanol concentrations in rats and in men after a single dose of aspartame.

    PubMed

    Davoli, E; Cappellini, L; Airoldi, L; Fanelli, R

    1986-03-01

    Serum methanol concentrations were measured in rats and in humans given oral aspartame. The dose given to rats was the FDA's projected 99th percentile daily intake for humans, assuming aspartame were to replace all sucrose sweeteners in the diet (34 mg/kg). Four male adult volunteers each received 500 mg, equivalent to 6-8.7 mg/kg, which is approximately the FDA's estimate of mean daily human consumption. Both treatments caused a rise in serum methanol. In rats the mean peak value was 3.1 mg/litre 1 hr after administration; serum methanol returned to endogenous values 4 hr after treatment. In the men, the mean rise over endogenous values was 1.06 mg/litre after 45 min. Two hours after treatment, serum methanol had returned to basal levels. The temporary serum methanol increase showed peak values within the range of individual basal levels.

  9. A single subcutaneous dose of tramadol for mild to moderate musculoskeletal trauma in the emergency department

    PubMed Central

    Cardozo, Alejandro; Silva, Carlos; Dominguez, Luis; Botero, Beatriz; Zambrano, Paulo; Bareno, Jose

    2014-01-01

    BACKGROUND: Mild to moderate musculoskeletal trauma is a common cause for an emergency room visit, and frequent pain is one of the cardinal symptoms of consultation. The objective of this study is to assess the perception of a single subcutaneous dose of 50 mg tramadol for pain management in patients with mild to moderate musculoskeletal trauma, likewise to appraise the perception of pain by subcutaneous injection. METHODS: A total of 77 patients, who met inclusion criteria, received a single subcutaneous dose of tramadol. Pain control was evaluated based on the verbal numerical pain scale (0–10) at baseline, 20 and 60 minutes; similarly, pain perception was evaluated secondary to subcutaneous injection of the analgesic. RESULTS: On admission, the average pain perceived by patients was 8; twenty minutes later, 89% of the patients reported five or less, and after sixty minutes, 94% had three or less on the verbal numerical pain scale. Of the patients, 88% reported pain perception by verbal numeric scale of 3 or less by injection of the drug, and 6.5% required a second analgesic for pain control. Two events with drug administration (soft tissue infection and mild abdominal rectus injection) were reported. CONCLUSION: We conclude that a single subcutaneous dose of tramadol is a safe and effective option for the management of patients with mild to moderate pain and musculoskeletal disease in the emergency department. PMID:25548601

  10. Single Dose Propranolol Does Not Affect Physiologic or Emotional Reactivity to Smoking Cues

    PubMed Central

    Pachas, Gladys N.; Gilman, Jodi; Orr, Scott P.; Hoeppner, Bettina; Carlini, Sara V.; Loebl, Tsafrir; Nino, Johanna; Pitman, Roger K.; Evins, A. Eden

    2015-01-01

    Background Smoking cue exposure reactivates salient smoking-related memories, triggering craving to smoke, a phenomenon associated with maintenance of smoking behavior and relapse after periods of abstinence. Acute β-adrenergic blockade with propranolol reduces physiologic reactivity during subsequent recollection of traumatic events by inhibiting reconsolidation of reactivated memories in a process called memory reconsolidation blockade. Objective To determine whether a single dose of propranolol prior to retrieval of smoking-related memories reduces subsequent physiologic reactivity to personally salient smoking imagery scripts in current smokers. Methods Fifty-four overnight-abstinent, adult smokers received single dose propranolol or placebo prior to reactivation of smoking-related memories in a randomized, double-blind, placebo-controlled trial and resumed smoking afterward. One week later, skin conductance (SC), heart rate (HR) left corrugator electromyogram (EMG), self-reported emotional state and craving were assessed following script driven imagery with neutral and personalized smoking-related scripts. Results Smoking scripts were associated with increased physiologic activation (SC, HR, EMG), craving and negative emotional state compared with neutral scripts. Propranolol did not moderate the effect of script type on any outcome. Conclusion Personalized smoking script-driven imagery robustly increased physiologic activation, negative emotional state and craving, and a single dose of propranolol prior to memory reactivation did not moderate this effect. PMID:25413896

  11. Single-neuron axonal pathfinding under geometric guidance: low-dose-methylmercury developmental neurotoxicity test.

    PubMed

    Wei, Lina; Sweeney, Andrew J; Sheng, Liyuan; Fang, Yu; Kindy, Mark S; Xi, Tingfei; Gao, Bruce Z

    2014-09-21

    Because the nervous system is most vulnerable to toxicants during development, there is a crucial need for a highly sensitive developmental-neurotoxicity-test model to detect potential toxicants at low doses. We developed a lab-on-chip wherein single-neuron axonal pathfinding under geometric guidance was created using soft lithography and laser cell-micropatterning techniques. After coating the surface with L1, an axon-specific member of the Ig family of cell adhesion molecules (CAMs), and optimizing microunit geometric parameters, we introduced low-dose methylmercury, a well-known, environmentally significant neurotoxicant, in the shared medium. Its developmental neurotoxicity was evaluated using a novel axonal pathfinding assay including axonal turning and branching rates at turning points in this model. Compared to the conventional neurite-outgrowth assay, this model's detection threshold for low-dose methylmercury was 10-fold more sensitive at comparable exposure durations. These preliminary results support study of developmental effects of known and potential neurotoxicants on axon pathfinding. This novel assay model would be useful to study neuronal disease mechanisms at the single-cell level. To our knowledge, the potential of methylmercury chloride to cause acute in vitro developmental neurotoxicity (DNT) at such a low dosage has not been reported. This is the first DNT test model with high reproducibility to use single-neuron axonal pathfinding under precise geometric guidance. PMID:25041816

  12. Cognitive effects of methylphenidate in healthy volunteers: a review of single dose studies.

    PubMed

    Linssen, A M W; Sambeth, A; Vuurman, E F P M; Riedel, W J

    2014-06-01

    Methylphenidate (MPH), a stimulant drug with dopamine and noradrenaline reuptake inhibition properties, is mainly prescribed in attention deficit hyperactivity disorder, is increasingly used by the general population, intending to enhance their cognitive function. In this literature review, we aim to answer whether this is effective. We present a novel way to determine the extent to which MPH enhances cognitive performance in a certain domain. Namely, we quantify this by a percentage that reflects the number of studies showing performance enhancing effects of MPH. To evaluate whether the dose-response relationship follows an inverted-U-shaped curve, MPH effects on cognition are also quantified for low, medium and high doses, respectively. The studies reviewed here show that single doses of MPH improve cognitive performance in the healthy population in the domains of working memory (65% of included studies) and speed of processing (48%), and to a lesser extent may also improve verbal learning and memory (31%), attention and vigilance (29%) and reasoning and problem solving (18%), but does not have an effect on visual learning and memory. MPH effects are dose-dependent and the dose-response relationship differs between cognitive domains. MPH use is associated with side effects and other adverse consequences, such as potential abuse. Future studies should focus on MPH specifically to adequately asses its benefits in relation to the risks specific to this drug.

  13. Beyond Gaussians: a study of single spot modeling for scanning proton dose calculation

    PubMed Central

    Li, Yupeng; Zhu, Ronald X.; Sahoo, Narayan; Anand, Aman; Zhang, Xiaodong

    2013-01-01

    Active spot scanning proton therapy is becoming increasingly adopted by proton therapy centers worldwide. Unlike passive-scattering proton therapy, active spot scanning proton therapy, especially intensity-modulated proton therapy, requires proper modeling of each scanning spot to ensure accurate computation of the total dose distribution contributed from a large number of spots. During commissioning of the spot scanning gantry at the Proton Therapy Center in Houston, it was observed that the long-range scattering protons in a medium may have been inadequately modeled for high-energy beams by a commercial treatment planning system, which could lead to incorrect prediction of field-size effects on dose output. In the present study, we developed a pencil-beam algorithm for scanning-proton dose calculation by focusing on properly modeling individual scanning spots. All modeling parameters required by the pencil-beam algorithm can be generated based solely on a few sets of measured data. We demonstrated that low-dose halos in single-spot profiles in the medium could be adequately modeled with the addition of a modified Cauchy-Lorentz distribution function to a double-Gaussian function. The field-size effects were accurately computed at all depths and field sizes for all energies, and good dose accuracy was also achieved for patient dose verification. The implementation of the proposed pencil beam algorithm also enabled us to study the importance of different modeling components and parameters at various beam energies. The results of this study may be helpful in improving dose calculation accuracy and simplifying beam commissioning and treatment planning processes for spot scanning proton therapy. PMID:22297324

  14. Dose rate effect on micronuclei induction in human blood lymphocytes exposed to single pulse and multiple pulses of electrons.

    PubMed

    Acharya, Santhosh; Bhat, N N; Joseph, Praveen; Sanjeev, Ganesh; Sreedevi, B; Narayana, Y

    2011-05-01

    The effects of single pulses and multiple pulses of 7 MV electrons on micronuclei (MN) induction in cytokinesis-blocked human peripheral blood lymphocytes (PBLs) were investigated over a wide range of dose rates per pulse (instantaneous dose rate). PBLs were exposed to graded doses of 2, 3, 4, 6, and 8 Gy of single electron pulses of varying pulse widths at different dose rates per pulse, ranging from 1 × 10(6) Gy s(-1) to 3.2 × 10(8) Gy s(-1). Different dose rates per pulse were achieved by changing the dose per electron pulse by adjusting the beam current and pulse width. MN yields per unit absorbed dose after irradiation with single electron pulses were compared with those of multiple pulses of electrons. A significant decrease in the MN yield with increasing dose rates per pulse was observed, when dose was delivered by a single electron pulse. However, no reduction in the MN yield was observed when dose was delivered by multiple pulses of electrons. The decrease in the yield at high dose rates per pulse suggests possible radical recombination, which leads to decreased biological damage. Cellular response to the presence of very large numbers of chromosomal breaks may also alter the damage.

  15. Single-Dose Local Simvastatin Injection Improves Implant Fixation via Increased Angiogenesis and Bone Formation in an Ovariectomized Rat Model

    PubMed Central

    Tan, Jie; Yang, Ning; Fu, Xin; Cui, Yueyi; Guo, Qi; Ma, Teng; Yin, Xiaoxue; Leng, Huijie; Song, Chunli

    2015-01-01

    Background Statins have been reported to promote bone formation. However, taken orally, their bioavailability is low to the bones. Implant therapies require a local repair response, topical application of osteoinductive agents, or biomaterials that promote implant fixation. Material/Methods The present study evaluated the effect of a single local injection of simvastatin on screw fixation in an ovariectomized rat model of osteoporosis. Results Dual-energy X-ray absorptiometry, micro-computed tomography, histology, and biomechanical tests revealed that 5 and 10 mg simvastatin significantly improved bone mineral density by 18.2% and 22.4%, respectively (P<0.05); increased bone volume fraction by 51.0% and 57.9%, trabecular thickness by 16.4% and 18.9%, trabeculae number by 112.0% and 107.1%, and percentage of osseointegration by 115.7% and 126.3%; and decreased trabeculae separation by 34.1% and 36.6%, respectively (all P<0.01). Bone mineral apposition rate was significantly increased (P<0.01). Furthermore, implant fixation was significantly increased (P<0.05), and bone morphogenetic protein 2 (BMP2) expression was markedly increased. Local injection of a single dose of simvastatin also promoted angiogenesis. Vessel number, volume, thickness, surface area, and vascular volume per tissue volume were significantly increased (all P<0.01). Vascular endothelial growth factor (VEGF), VEGF receptor-2, von Willebrand factor, and platelet endothelial cell adhesion molecule-1 expression were enhanced. Conclusions A single local injection of simvastatin significantly increased bone formation, promoted osseointegration, and enhanced implant fixation in ovariectomized rats. The underlying mechanism appears to involve enhanced BMP2 expression and angiogenesis in the target bone. PMID:25982481

  16. Population pharmacokinetic model of THC integrates oral, intravenous, and pulmonary dosing and characterizes short- and long-term pharmacokinetics.

    PubMed

    Heuberger, Jules A A C; Guan, Zheng; Oyetayo, Olubukayo-Opeyemi; Klumpers, Linda; Morrison, Paul D; Beumer, Tim L; van Gerven, Joop M A; Cohen, Adam F; Freijer, Jan

    2015-02-01

    Δ(9)-Tetrahydrocannobinol (THC), the main psychoactive compound of Cannabis, is known to have a long terminal half-life. However, this characteristic is often ignored in pharmacokinetic (PK) studies of THC, which may affect the accuracy of predictions in different pharmacologic areas. For therapeutic use for example, it is important to accurately describe the terminal phase of THC to describe accumulation of the drug. In early clinical research, the THC challenge test can be optimized through more accurate predictions of the dosing sequence and the wash-out between occasions in a crossover setting, which is mainly determined by the terminal half-life of the compound. The purpose of this study is to better quantify the long-term pharmacokinetics of THC. A population-based PK model for THC was developed describing the profile up to 48 h after an oral, intravenous, and pulmonary dose of THC in humans. In contrast to earlier models, the current model integrates all three major administration routes and covers the long terminal phase of THC. Results show that THC has a fast initial and intermediate half-life, while the apparent terminal half-life is long (21.5 h), with a clearance of 38.8 L/h. Because the current model characterizes the long-term pharmacokinetics, it can be used to assess the accumulation of THC in a multiple-dose setting and to forecast concentration profiles of the drug under many different dosing regimens or administration routes. Additionally, this model could provide helpful insights into the THC challenge test used for the development of (novel) compounds targeting the cannabinoid system for different therapeutic applications and could improve decision making in future clinical trials.

  17. Application of optically stimulated luminescence technique to evaluate simultaneously accumulated and single doses with the same dosimeter

    NASA Astrophysics Data System (ADS)

    Malthez, Anna Luiza M. C.; Freitas, Marcelo B.; Yoshimura, Elisabeth M.; Button, Vera L. S. N.

    2014-02-01

    Optically stimulated luminescence dosimeters (OSLD) can be read several times with a negligible loss (degradation) of signal. In this work, we explore this OSL property to estimate simultaneously the accumulated and single doses using a unique Al2O3 dosimeter, irradiated repeated times along over 4 months. This was done through several irradiations of OSLD (Landauer Luxel Dots) with two energies (28 keV X-rays and 1.25 MeV Co-60 gamma rays) and several doses distributed over time. Thermoluminescent dosimeters (TLD) were used as a reference to compare the estimated doses obtained with OSLD. For each irradiation, and both energies, a calibration curve was evaluated with OSLD and TLD to estimate the dose values. The OSL readouts were made with a MicroStar (Landauer) OSL reader. To estimate background (BG) over time, a set of OSLD and TLD (Bycron TLD100) was not irradiated and BG was monitored at each readout section. After irradiations, the OSL and TL signals were converted to dose and values were compared. As a set of OSLD suffered no bleaching after the readouts, it was possible to estimate simultaneously the accumulated and single doses with a unique OSLD. Each single dose was estimated through the subtraction of successive accumulated doses determined for each single OSLD. We concluded that the single doses determined by OSL and TL techniques were compatible, and that the accumulated dose, obtained with OSL technique was comparable to the sum of single doses determined with TLD. We can conclude that using OSL technique and Al2O3 dosimeters it is possible to estimate simultaneously accumulated and single doses with the same dosimeter irradiated with low or high energy photons.

  18. Individually dosed oral drug administration to socially-living transponder-tagged mice by a water dispenser under RFID control.

    PubMed

    Santoso, Ariane; Kaiser, Alexander; Winter, York

    2006-06-15

    The sensitivity of behavioral and physiological parameters to even mildly stressful experiences such as drug injections creates a need for alternative methods. We have established a method of stress-free administration of drugs via drinking water that allows multiple, individually specific and exact dosages, even for socially-housed animals. The drug solution is supplied by a dispenser with automated volume control. Animals are PIT microchip-tagged with RFID transponders and identified in realtime at the water port. Computer control permits preprogramming of individual reward quantities so that drug administration is terminated after an individual has collected its daily dose. For our experiments, the substance 5-bromo-2'-deoxyuridine (BrdU) was given as a marker of proliferating cells that we quantified in the hippocampus of adult mice. Experimental groups received BrdU either via intraperitoneal injections or orally via the water dispensers. Immunohistochemical staining of BrdU-positive cells was of the same quality after oral administration as after injection. BrdU-positive cells did not differ statistically in cell numbers. Thus, water dispensers under transponder control allow the individual and stress-free application of drugs even to group-living animals without disturbing their behavior. This is useful where a complex temporal protocol of application is required, and for phenotyping experiments combining behavioral tests with neural, cellular or molecular analyses.

  19. Hepatic and renal metallothionein induction following single oral administration of gallium arsenide in rats.