Microg Dose Research Articles

Folic acid fortification and public health: Report on threshold doses above which unmetabolised folic acid appear in serum

BackgroundAll flour in the USA is fortified with folic acid at a level of 140 μg/100 g which is estimated to supply an extra 100 μg daily to the average diet. Some researchers have advocated that this be increased to double and even four times this amount. Based on previous research these higher levels are likely to lead to the appearance of unmetabolised vitamin in the circulation, which may have safety implications for sub-groups of the population. The UK and the Republic of Ireland will likely introduce mandatory fortification also in the next year or so.The aim of this study was to capture the short-term effect of folic acid fortification on unmetabolised folic acid in serum after chronic consumption of folic acid.MethodsAfter pre-saturation with 400 μg folic acid supplements daily for 14-weeks, healthy folate replete adults (n = 20) consumed folic acid fortified bread, at three different levels (400 μg, 200 μg, 100 μg) over a period of one week each. The dose was administered in two-equal sized slices consumed at 09.00 hrs and 13.00 hrs. Serum samples for total folate and folic acid were collected at baseline, after 14-weeks of supplementation, and pre and post (at 1, 2, 3 and 4 hours) each dose tested.ResultsUnmetabolised folic acid was detected after the 14-week supplementation period. Folic acid was not detected in either the 200 μg or 100 μg (current US regime) doses tested but was present at the highest level (400 μg) tested.ConclusionOur findings suggest that persons exposed to the current US fortification programme supplying an average of 100 μg per day or less are unlikely to have unmetabolised folic acid in serum. It also seems that daily consumption of the higher level of 200 μg or less is unlikely to be problematic. Increasing the level however to 400 μg on the other hand is likely to lead to unmetabolised folic acid appearance.

The preclinical testing of a formaldehyde inactivated Ross River virus vaccine designed for use in humans

Ross River virus was grown in industrial facilities in vaccine-certified Vero cells in the absence of serum, inactivated using standard formalin-inactivation protocols, treated with Benzonase to digest host cell DNA and purified on a sucrose gradient. Mice given two subcutaneous injections of 0.625 microg of this vaccine or two doses of 0.156 microg vaccine with aluminium hydroxide adjuvant failed to develop a detectable viraemia after intravenous challenge with 10(6)TCID50 of the prototype strain of Ross River virus (T48). Guinea pigs immunised with one or two10 microg doses of vaccine with adjuvant also failed to develop a detectable viraemia following a similar challenge. The levels of neutralising antibody (neutralisation index 1.9-3.1) in the mice protected against challenge with 10(6)TCID50 Ross River virus were similar to those in 16 former epidemic polyarthritis patients (1.1-3.5) who had not experienced a second clinical infection with Ross River virus in the 20 years following their initial infection.

Neosaxitoxin as a Local Anesthetic

Neosaxitoxin is a phycotoxin that reversibly blocks the voltage-gated sodium channels at the neuronal level. Its activity results in blocking the axonal conduction, stopping the propagation of the nerve impulse. The objective of the present work was to evaluate neosaxitoxin as a local anesthetic in a human trial. The authors conducted a randomized, double-blind, placebo-controlled trial with 10 healthy volunteers. Subcutaneous injections were made in the middle posterior skin of the calf: one leg received 50 microg neosaxitoxin, and the contra-lateral leg received placebo. The anesthetic effect was evaluated using a standardized human sensory and pain model. TSA II Neurosensory Analyzer (Medoc Ltd, Minneapolis, MN) and von Frey technique were used to evaluate five parameters: sensory threshold for warm and cold, pain thresholds for heat and cold, and mechanical touch perception threshold. Measurements were made 0, 1, 3, 6, 9, 12, 16, 24, and 48 h after the injections. For all the patients, effective and complete blocking of the evaluated parameters was obtained. As the blocking began to revert gradually, heat pain was the first to return to normal values after 3 h. Cold pain was the longest sensation abolished, achieving 24 h of blockade. The toxin was undetected in blood and urine samples. No adverse reactions to neosaxitoxin were detected. Neosaxitoxin showed an effective local anesthetic effect when injected in the subcutaneous plane. The efficacy of a 50-microg dose of neosaxitoxin was shown. This is the first report of neosaxitoxin as a local anesthetic in a human trial.

Indacaterol, a novel inhaled 2-agonist, provides sustained 24-h bronchodilation in asthma

The present study examined the bronchodilator and safety profiles of single-dose indacaterol in intermittent or persistent asthma. In the present double-blind crossover study, 42 patients were randomised to receive single doses of indacaterol (50, 100, 200 and 400 microg) or placebo via a hydrofluoroalkane pressurised metered-dose inhaler. The primary efficacy comparisons were the per cent changes in forced expiratory volume in one second (FEV(1 )) between indacaterol and placebo 30 min and 21 h post-dose. All doses resulted in prolonged bronchodilation, with indacaterol 200 and 400 microg meeting pre-specified efficacy criteria. The mean percentage increases in FEV(1) from placebo with indacaterol 200 and 400 microg were 7.6 and 14.9%, respectively, at 30 min, and 7.5 and 10.4%, respectively, at 21 h post-dose. At these doses, changes in mean FEV(1) relative to placebo were statistically significant from 5 min to 25 h, inclusive. At 5 min, the geometric least squares mean values for FEV(1) were 3.08 and 3.22 L for the 200 and 400 microg doses, respectively, compared with 2.99 L for placebo. At 24 h after dosing, the baseline-adjusted geometric least square mean FEV(1) was 3.13, 3.11, 3.24 and 3.30 L for indacaterol 50, 100, 200 and 400 microg, respectively, and 2.98 L for placebo. All treatments were well tolerated. Once-daily indacaterol at doses of 200 and 400 microg provided sustained 24-h bronchodilation, with a rapid onset and a good tolerability and safety profile.

Synthetic Adrenocorticotropic Hormone Stimulation Tests in Healthy Neonatal Foals

Cosyntropin (adrenocorticotropic hormone [ACTH]) stimulation tests are used to evaluate adrenal function. Low-dose ACTH stimulation tests are the most accurate method for diagnosing relative adrenal insufficiency in critically ill humans but have not been evaluated in foals. Peak serum cortisol concentrations in healthy foals will not be significantly different after intravenous administration of 1, 10, 100, and 250 microg of cosyntropin. 14 healthy neonatal foals, 3-4 days of age. A randomized cross-over model was used in which cosyntropin (1, 10, 100, or 250 microg) was administered intravenously on days 3 and 4 of life. Blood samples were collected before and 30, 60, 90, 120, and 150 minutes after administration of cosyntropin for determination of serum cortisol concentration. Serum cortisol concentrations did not significantly increase after administration of 1 microg of cosyntropin. Cortisol concentration peaked 30 minutes after administration of 10 microg of cosyntropin and 90 minutes after 100 and 250 microg of cosyntropin. There was no relationship between cosyntropin dose and serum cortisol concentration at 30 minutes. Compared with the 10-microg dose, 100 and 250 microg of cosyntropin induced significantly greater cortisol concentrations at 90 minutes, at which point the 10-microg cosyntropin-dose cortisol values were indistinguishable from baseline. There was no significant difference in the area under the cortisol concentration curve between the 100- and 250-microg doses. No effect of day of testing or foal weight on peak cortisol concentration was detected. The results of this study suggest that 10- and 100-microg doses of cosyntropin would be appropriate for evaluating adrenal function in neonatal foals.

Absorption of Fentanyl from Fentanyl Buccal Tablet in Cancer Patients With or Without Oral Mucositis

Patients with cancer, particularly those undergoing chemotherapy or radiotherapy, may develop oral mucositis. This is the first study to investigate the absorption profile of fentanyl buccal tablet (FBT) - an effervescent formulation of fentanyl indicated for the management of breakthrough pain in opioid-tolerant cancer patients - in patients with or without oral mucositis. In this open-label study, patients with or without oral mucositis self-administered a single 200 microg dose of FBT by placing the tablet between the upper gum and cheek above a molar tooth. Venous blood samples for measurement of plasma fentanyl concentrations were collected at regular intervals up to 8 hours following FBT administration. Parameters of interest included maximum plasma concentration (C(max)), time to reach C(max) (t(max)), area under the plasma concentration-time curve from time zero to 8 hours (AUC(8)), and AUC from time zero to the median t(max) (AUC(tmax)(')). Adverse events were monitored throughout the study. Oral mucosal examinations and measurements of vital signs were performed at intervals up to 8 hours following FBT administration. Sixteen patients, 8 with and 8 without oral mucositis, received FBT and completed the study. The severity of oral mucositis was mild in the patients exhibiting this condition. Median C(max) values were comparable: 1.14 ng/mL (range 0.26-2.69 ng/mL) in patients with mucositis, and 1.21 ng/mL (range 0.21-2.34 ng/mL) in patients without mucositis. The t(max) was not significantly different in the two groups: median t(max) was 25.0 min (range 15-45 min) in patients with mucositis and 22.5 min (range 10-121 min) in patients without mucositis. Median AUC(tmax') values were 0.17 ng . h/mL (range 0.04-0.52 ng . h/mL) in patients with mucositis, and 0.20 ng . h/mL (range 0.00-0.65 ng . h/mL) in patients without mucositis. The corresponding AUC(8) values were 2.05 ng . h/mL (range 1.16-3.83 ng . h/mL) and 1.55 ng . h/mL (range 0.74-3.07 ng . h/mL), respectively. FBT was generally well tolerated in this small group. No application site adverse events or changes in oral mucosal assessments were reported. The absorption profile of a single dose of FBT 200 microg was similar in patients with or without mild oral mucositis. The compound was generally well tolerated.

Cutaneous and systemic effects of varying doses of brown recluse spider venom in a rabbit model.

To ascertain whether a dose response exists between the dose of brown recluse spider venom (BRSV) and the cutaneous and coagulation effects in a rabbit model. Cutaneous necrosis is a serious complication of brown recluse spider envenomation (spider bite with venom). Disseminated intravascular coagulation (DIC) is a dreaded complication of brown recluse envenomation in humans. New Zealand white (NZW) rabbits have proved to be a model for the study of therapeutic regimens to prevent skin necrosis after spider bites. We studied the venom's effects on the skin and the coagulation mechanism in this rabbit model to determine if a clear dose-response relationship could be established. Establishment of a dose-response relationship is an important first step in determining if the NZW rabbit is a suitable model to study both cutaneous and systemic effects of the venom. Thirty-six NZW rabbits were divided into three groups. One group received a saline injection, and the other two groups received a 4.0 microg or a 10.0 microg dose of purified BRSV intradermally into the skin on the dorsum of the back. Blood was collected at baseline, 24, 48, and 72 hours. Tissue specimens were obtained after seven days during the animal necropsy and gross and microscopic pathology examination was conducted to assess tissue damage. Measurements included complete blood count (CBC); platelets; PT; activated partial thromboplastin time (APTT); fibrinogen (clottable, immunological); coagulation factors II, V, VII, VIII, IX, X, XI, XII; anti-thrombin (AT); alpha-2 antiplasmin (AP); Protein C (PC); mixing studies; lupus anticoagulant screening; plasminogen; thrombin-antithrombin; fibrin degradation products (FDP); d-dimer; and thrombin time. Gross pathology results were consistent with previous studies that used higher doses of BRSV. The WBC and platelet counts decreased at 24 hours in the two groups receiving the BRSV (p < 0.05). BRSV produced a dose related prolongation in the APTT (p < 0.05). Levels of fibrinogen as well as factors V, VII, VIII, IX, X, AT, and AP (p < 0.05) were increased in response to the BRSV. Protein C decreased at 24 hours (p < 0.05) and remained low in other time points. Mixing studies corrected the prolonged APTTs to normal ranges. Factor IIXI and XII showed no significant alteration in response to the BRSV. In the model, both the size and depth of the eschar were dose-related. We also observed a dose related elevation in the APTT that corrected with mixing studies. The dose-response relationship suggests direct interference by a component of the venom, rather than an idiosyncratic response. We did not detect a deficiency of commonly measured coagulation factors or evidence of a lupus anticoagulant. Protein C demonstrated a decrease. Although DIC did not occur in this rabbit model, a dose-related elevation in APTT was noted. The finding that the elevation corrected with mixing studies suggests that a plasma factor is essential in the coagulopathy associated with brown recluse envenomation. Further studies to identify this factor could shed light on human coagulopathy following envenomation.

Granulocyte colony stimulating factor in patients with large acute myocardial infarction: Results of a pilot dose-escalation randomized trial

Preclinical studies suggest that administration of cytokines to mobilize stem cells and alter the postinfarction inflammatory cardiac milieu may enhance left ventricular function and survival. Eighteen patients were randomized in a 2:1 double-blind fashion to granulocyte colony stimulating factor (G-CSF) (at 5 escalating to 10 microg/kg per day subcutaneously for 5 days [6 patients in each group]) or matching placebo. Principal safety and efficacy end points were rupture-free survival and recovery of left ventricular function, respectively. Mobilization into the systemic circulation of precursor CD34+ and CD117+ stem cells at 30 days were also assessed. Baseline characteristics of the 3 groups were well matched. Mean +/- SD creatine kinase-MB maximum was 349 (169) IU. Follow-up averaged 30 +/- 6, 21 +/- 11, and 11 +/- 6 months in the 3 groups, respectively. Precursor cell mobilization increased by a factor of 5 to 7 in the G-CSF-treated patients. There were no deaths or myocardial ruptures leading to tamponade through 30 days. Baseline and 30-day left ventricular ejection fraction in the placebo, 5-microg, and 10-microg dose groups were 33.7% (1.6) and 41.7% (8.2), 36.8% (7.5) and 41.3% (10.3), and 33.5% (4.8) and 38.7% (7.3), respectively (P = NS for all between-group comparisons). No differences between the G-CSF and placebo groups were noted in any other measure of left ventricular systolic or diastolic function 30 days after infarction. Despite demonstrated mobilization of precursor stem cells in a timely fashion, in this small, pilot-scale randomized trial involving patients with large myocardial infarction, we were unable to demonstrate improvement in left ventricular function at 30 days.

αvβ3 Integrin‐targeting of intraperitoneally growing tumors with a radiolabeled RGD peptide

Ovarian cancer is the fourth most common cause of cancer deaths among females in the western world after cancer of the breast, colon and lung. The inability to control the disease within the peritoneal cavity is the major cause of treatment failure in patients with ovarian cancer. The majority of ovarian carcinomas express the alpha(v)beta(3) integrin. Here we studied the tumor targeting potential of an (111)In-labeled cyclic RGD peptide in athymic BALB/c mice with intraperitoneally (i.p.) growing NIH:OVCAR-3 human ovarian carcinoma tumors. The cyclic RGD peptide, c(RGDfK)E, was synthesized, conjugated with DOTA and radiolabeled with (111)In. The targeting potential of (111)In-DOTA-E-c(RGDfK) was studied in athymic mice with i.p. growing NIH:OVCAR-3 xenografts and the optimal dose of this compound was determined (0.01 microg up to 10 microg). The biodistribution at optimal peptide dose was determined at various time points (0.5 up to 72 hr). Furthermore, the therapeutic potential of (177)Lu-DOTA-E-c(RGDfK) was studied in this model. Two hours after i.p. administration, (111)In-DOTA-E-c(RGDfK) showed high and specific uptake in the i.p. growing tumors. Optimal uptake in the i.p. growing tumors was observed at a 0.03-0.1 microg dose range. Tumor uptake of (111)In-DOTA-E-c(RGDfK) peaked 4 hr p.i. [(38.8 +/- 2.7)% ID/g], gradually decreasing at later time points [(24.0 +/- 4.1)% ID/g at 48 hr p.i.]. Intraperitoneal growth of OVCAR-3 could be significantly delayed by injecting 37 MBq (177)Lu-labeled peptide i.p. Radiolabeled DOTA-E-c(RGDfK) is suitable for targeting of i.p. growing tumors and potentially can be used for peptide receptor radionuclide therapy of these tumors.

Single Dose of Anti-Transforming Growth Factor-β 1 Monoclonal Antibody Enhances Liver Regeneration After Partial Hepatectomy in Biliary-Obstructed Rats

Transforming growth factor (TGF) beta is a potent inhibitor of hepatocyte DNA synthesis and liver regeneration. TGF-beta(1) expression progressively increases in obstructive jaundice. We investigated the effect of TGF-beta(1) blockage on liver regeneration in rats induced with obstructive jaundice. Male Wistar-albino rats were divided into three groups: sham, control, and study groups. In the study and control groups, the common bile duct was ligated and divided, and 7 days later a partial hepatectomy was performed. In the study group, anti-TGF-beta(1) monoclonal antibody (10-microg single dose) was administered immediately after the 70% hepatectomy. In the control group, those rats in which obstructive jaundice was induced received normal saline after the 70% hepatectomy, and nonjaundiced rats received anti-TGF-beta(1) monoclonal antibody after the 70% hepatectomy. Rats were sacrificed after 48 or 72 h. Relative liver weight, AST, ALT, total and conjugated bilirubin, and TGF-beta(1) levels were measured. The mitotic index and proliferating cell nuclear antigen (PCNA) labeling index were evaluated as histopathologic parameters. At 72 h, the TGF-beta(1) level in the study group was similar to that in the sham group, whereas TGF-beta(1) in the study group was significantly lower than that of the jaundiced control group at 48 or 72 h (P < 0.001). The relative liver weight, mitotic index, and PCNA labeling index were significantly higher in the study group than in the jaundiced control group at 48 and 72 h (P < 0.001). The AST, ALT, and TGF-beta(1) levels were significantly higher in the jaundiced control group compared to the study group after 48 and 72 h, whereas these values were significantly lower in the nonjaundiced control group (P < 0.001). In obstructive jaundiced rats, TGF-beta(1) blockage with anti-TGF-beta(1) monoclonal antibody after liver resection improved liver regeneration both morphologically and functionally.

Disposition and pharmacokinetics of a lubricant contaminant, 2,6‐di‐tert‐butyl 4‐nitrophenol, in grafted human skin

Disposition and uptake/elimination profiles of topical 2,6-di-t-butyl, 4-nitrophenol (DBNP), the nitrated metabolite of an antioxidant additive of lubricant and hydraulic fluids was quantified in human skin grafted on athymic mice after a single topical 75 microg dose in corn oil. DBNP was quantified throughout the stratum corneum (SC), epidermis (E) and dermis (D) in punch biopsies collected from treated skin 0.5, 1, 2, 4, 8 and 24 h after application. SC samples were harvested from the treated skin with 20 adhesive discs. E and D were generated from the biopsy using a manual sectioning method. Detectable DBNP concentrations were measured in all skin compartments at all time points investigated. The Cmax of DBNP in SC was 1663 +/- 602 microg cm(-3), and approximately 30 and approximately 300 fold greater than the Cmax for E and D, respectively. Tmax occurred at 1.0, 0.5 and 1.0 in the SC, E and D, respectively. Over a 24 h interval (AUC0-24 h) there was 52 and 520 fold more DBNP in the SC than E and D, respectively. The elimination half-life of DBNP was 11 h from the SC and 9 h from both E and D. Thus, DBNP was quickly absorbed into the outermost layer of skin and established a steep concentration profile through human skin. The data are consistent with the vast majority of DBNP remaining on the surface (77%) or within human skin (15%) in vivo with only 0.2% of the DBNP dose quantified in the systemic blood circulation.

Immunogenicity and tolerance of ascending doses of a recombinant protective antigen (rPA102) anthrax vaccine: A randomized, double-blinded, controlled, multicenter trial

We report the results of a phase I dose escalation, safety and immunogenicity trial of a new recombinant protective antigen (rPA102) anthrax vaccine. Hundred healthy volunteers were randomized in a 4:1 ratio to receive intramuscular doses of rPA102 in the following formulations: 5, 25, 50, or 75 microg of rPA102 in 82.5 microg aluminum hydroxide adjuvant at 0, 4, and 8 weeks; or the US licensed Anthrax Vaccine Adsorbed (AVA) at weeks 0 and 4. Local reactogenicity (mostly pain) was more common with AVA than with rPA102 following the first (94.7% versus 44.4%; p < 0.001) and the second (84.2% versus 35.4%; p < 0.001) vaccinations. Systemic reactogenicity (mostly headache) was more common among rPA102 vaccinees, but only following the first vaccination (49.4% versus 15.8%; p = 0.025). A dose-response relationship for anti-PA antibodies was present after the 2nd and 3rd vaccinations. Two weeks following the 2nd vaccination, the geometric mean titers (GMT) for lethal toxin neutralization activity (TNA), for the 5, 25, 50 and 75 microg rPA102 and AVA groups were 38.6, 75.4, 373.9, 515.3, and 855.2, respectively. The geometric mean concentrations (GMC) measured by anti-PA IgG ELISA were 3.7, 11.5, 25.9, 44.1, and 171.6, respectively. Two weeks following the 3rd vaccination, TNA GMTs for the four rPA102 groups, were: 134.7, 719.7, 2116.6, 2422.4; and ELISA GMCs were: 22.9, 104.7, 196.4, and 262.6, respectively. No clinically serious or dose-related toxicity or reactogenicity was observed. The TNA response after two injections of the 75 microg dose of rPA102 was similar to the response after two injections of AVA. The third rPA102 vaccination substantially increased the antibody response.

Der p 1 peptide on virus-like particles is safe and highly immunogenic in healthy adults

In mice, highly repetitive antigens, such as those present on bacterial or viral surfaces, efficiently cross-link B-cell receptors and therefore induce strong IgG responses. In this study we covalently coupled a synthetic 16-amino-acid sequence of the allergen Der p 1 to a virus-like particle derived from the bacteriophage Qbeta (Qbeta-Der p 1). We evaluated the safety and immunogenicity of Qbeta-Der p 1 in human subjects and compared different doses and routes of immunization. In a phase I trial 24 healthy volunteers were randomly assigned to one of 4 treatment groups. Group 1 received 50 microg of Qbeta-Der p 1 intramuscularly, group 2 received 50 microg of Qbeta-Der p 1 subcutaneously, group 3 received 10 microg of Qbeta-Der p 1 intramuscularly, and group 4 received 10 microg of Qbeta-Der p 1 subcutaneously. Boosting immunizations with 10 microg were given after 1 and 3 months. Antibody titers were measured after 1, 3, 4, 6, 12, and 18 months. The vaccine Qbeta-Der p 1 was well tolerated. Significant IgG responses were observed 4 weeks after a single injection. Individuals receiving 50 microg of the vaccine had significantly higher IgG titers than those vaccinated with 10 microg. However, the route of immunization (subcutaneous vs intramuscular) had no effect. In the 50-microg dose group, strong antibody responses against Der p 1 with average titers of 1:2000 were obtained. Vaccination with a peptide antigen covalently coupled to highly repetitive virus-like particles represents an adjuvant-free means of rapidly inducing high antibody titers in human subjects. Allergens coupled to virus-like particles can be used to enhance the efficiency of allergen-specific immunotherapy.

Plasma pharmacokinetics of desmopressin following sublingual administration: an exploratory dose-escalation study in healthy male volunteers

Desmopressin is usually administered intranasally in the treatment of central diabetes insipidus or nocturnal enuresis. The sublingual administration of desmopressin is expected to be an alternative to the intranasal route with advantages to children and to patients with allergic rhinitis or chronic rhinosinusitis. Therefore, the present study was carried out to explore the time-versus-concentration profile of desmopressin in plasma after sublingual administration to healthy volunteers. A total of 16 healthy male volunteers were enrolled in this open, exploratory, 1-period, randomized, dose-escalation study. Volunteers received a single sublingual dose of either 20, 40, 80, 160, 240 or 320 microg of desmopressin acetate. Desmopressin plasma concentrations were measured over a 12-hour period using a validated radioimmunoassay method. Safety and tolerability were assessed simultaneously. Plasma concentrations of desmopressin were below the lower limit of quantification (LLOQ) of 5 pg/ml for doses lower than 80 microg. For the doses of 160 - 320 microg the time-versus-concentration profiles were higher than the LLOQ. The area under the curve from 0 - 12 h (AUC0-12h) was 54.66 +/- 25.92 pg x h/ml after the 160 microg dose, 104.38 +/- 79.10 pg x h/ml following the 240 microg dose and 133.18 +/- 181.84 pg x h/ml following the 320 microg dose. Given the data from previous experiments, the time-versus-concentration profile of desmopressin in plasma after a sublingual dose of 240 microg appeared to be in the range of previously published data on an intranasal dose of 20 microg. Sublingual administration of desmopressin proved to be safe and was well tolerated by all volunteers. A very high inter-individual variability in desmopressin plasma concentrations was detected after sublingual administration. A sublingual dose of 240 microg of desmopressin appeared to result in a pharmacokinetic profile comparable to 20 microg administered intranasally. These data, however, need to be verified in a separate well-designed prospective clinical study.

CCL19 reduces tumour burden in a model of advanced lung cancer

Epstein–Barr virus-induced molecule 1 ligand chemokine (CCL19) is a CC chemokine that chemoattracts both dendritic cells (DC) and T lymphocytes. We evaluated the antitumour efficacy of CCL19 in a murine model of spontaneous bronchoalveolar cell carcinoma. These transgenic mice (CC-10 TAg) express the SV40 large T antigen under the Clara Cell promoter, develop bilateral, multifocal, pulmonary carcinomas and die at 4 months owing to progressive pulmonary tumour burden. To mimic therapy in late-stage disease, 3-month-old transgenic mice were treated with recombinant CCL19 (0.5 μg dose−1) by intranodal (axillary lymph node region) injection three times per week for 4 weeks. CCL19 treatment led to a marked reduction in tumour burden with extensive mononuclear infiltration of the tumours compared to diluent treated controls. Flow cytometric analyses showed significant increases in CD4 and CD8T cell subsets as well as DC in the lungs of CCL19-treated mice. Lung tissue cytokine profiles showed a shift towards immune stimulatory molecules with a decrease in the immunosuppressive cytokine TGF-β. Our findings show that CCL19 may serve as a potential immune stimulator and provide a strong rationale for the evaluation of CCL19 in cancer immunotherapy.

The role of the central thromboxane A2 in cardiovascular effects of a phospholipase A2 activator melittin administrated intracerebroventricularly in normotensive conscious rats

The current study was designed to determine the cardiovascular effect of centrally administrated melittin, a phospholipase A2 (PLA2) activator, and the mediation of central thromboxane A2 (TXA2) and its receptors in normotensive conscious rats. Studies were performed in normotensive male Sprague Dawley rats injected intracerebroventricularly (i.c.v.) with melittin. Melittin (1.5, 3.0, 6.0 microg/5.0 microl; i.c.v.) caused dose- and time-dependent increases in mean arterial pressure (MAP) and decrease in heart rate (HR). Maximal effects were observed 5-10 min after 3.0 microg dose of melittin. In order to test the mediation of central TXA2 and its central receptors in the cardiovascular effect of melittin, the rats were pretreated with furegrelate (500.0 microg; i.c.v.), a TXA2 synthesis inhibitor, and SQ-29548 (8.0 microg; i.c.v.), a TXA2 receptor antagonist, 15 min prior to melittin (3.0 microg). Furegrelate or SQ-29548 partially inhibited the pressor effect and bradycardia elicited by melittin. In conclusion, our findings show that centrally administered melittin increases MAP and decreases HR in conscious rats. Moreover, according to our findings, central TXA2 and its receptors may in part mediate melittin-induced cardiovascular effects.

A comparison of 2 extrafine hydrofluoroalkane-134a–beclomethasone formulations on methacholine hyperresponsiveness

Small airways inflammation is a recognized pathologic component of asthma, and it is postulated that the observed airway-wall remodeling in small airways could be due to uncontrolled inflammation in airways that are not penetrated by conventional inhaled corticosteroids. Thus, extrafine particle formulations of inhaled corticosteroids are of clinical interest. To compare 2 extrafine solution hydrofluoroalkane-134a formulations of beclomethasone dipropionate (Beclate and Qvar). Fifteen asthmatic patients (mean +/- SEM forced expiratory volume in 1 second [FEV1], 2.62 +/- 0.21 L; provocative concentration of methacholine causing a 20% decrease in FEV1 [PC20], 1.06 +/- 0.58) were randomized to completion in a placebo-controlled, double-blind, crossover manner to receive Beclate or Qvar at doses of 100 or 400 microg/d for 2 weeks, with a 1-week washout period before each randomized treatment. Methacholine hyperresponsiveness was the primary outcome measure. The 2 formulations were equivalent in terms of predefined equivalence limits of +/- 1 doubling dilution for PC20 at both doses: -0.25 (95% confidence interval [CI], -0.77 to 0.27) doubling dilution difference between the 100-microg doses and a 0.26 (95% CI, -0.29 to 0.82) doubling dilution difference between the 400-microg doses for the difference between Beclate and Qvar, respectively. Both formulations, at either dose, produced a statistically significant (P < .05) reduction in mean exhaled nitric oxide levels: 400 microg/d of Beclate, 14.1 ppb (95% CI, 5.6 to 22.6 ppb); and 400 microg/d of Qvar, 14.2 ppb (95% CI, 6.0 to 22.4 ppb). The higher doses produced a statistically significant (P < .05) reduction in early morning urinary cortisol-creatinine ratio (geometric mean fold suppression: Beclate, 1.48 [95% CI, 1.16 to 1.89]; and Qvar, 1.42 [95% CI, 1.12 to 1.79]). Both formulations significantly improved peak expiratory flow, FEV1, and forced expiratory flow between 25% and 75% of forced vital capacity at the higher doses (P < .05). Beclate and Qvar were equivalent for all primary and secondary outcome measures.

Oral vitamin B12 versus intramuscular vitamin B12 for vitamin B12 deficiency: a systematic review of randomized controlled trials

Vitamin B(12) deficiency is common, increasing with age. Most people are treated in primary care with intramuscular vitamin B(12). Several studies have reported equal efficacy of oral administration of vitamin B(12). We set out to identify randomized controlled trial (RCT) evidence for the effectiveness of oral versus intramuscular vitamin B(12) to treat vitamin B(12) deficiency. We conducted a systematic review searching databases for relevant RCTs. Outcomes included levels of serum vitamin B(12), total serum homocysteine and methylmalonic acid, haemoglobin and signs and symptoms of vitamin B(12) deficiency. Two RCTs comparing oral with intramuscular administration of vitamin B(12) met our inclusion criteria. The trials recruited a total of 108 participants and followed up 93 of these from 90 days to 4 months. In one of the studies, mean serum vitamin B(12) levels were significantly higher in the oral (643 +/- 328 pg/ml; n = 18) compared with the intramuscular group (306 +/- 118 pg/ml; n = 15) at 2 months (P < 0.001) and 4 months (1005 +/- 595 versus 325 +/- 165 pg/ml; P < 0.0005) and both groups had neurological responses. In the other study, serum vitamin B(12) levels increased significantly in those receiving oral vitamin B(12) and intramuscular vitamin B(12) (P < 0.001). The evidence derived from these limited studies suggests that 2000 microg doses of oral vitamin B(12) daily and 1000 microg doses initially daily and thereafter weekly and then monthly may be as effective as intramuscular administration in obtaining short-term haematological and neurological responses in vitamin B(12)-deficient patients.

Administration of baclofen, a γ‐aminobutyric acid type B agonist in the thalamic ventrobasal complex, attenuates allodynia in monoarthritic rats subjected to the ankle‐bend test

gamma-Aminobutyric acid type B (GABAB) receptors are involved in the modulation of neuronal activity in response to chronic noxious input. However, the effect of their activation in chronic inflammatory pain in relay thalamic nuclei such as the ventrobasal complex (VB) is not known. In this study, experimental groups of 2, 4, and 14 days monoarthritic (MA) rats were injected with saline (controls) or baclofen (0.875 microg), a specific GABAB receptor agonist, in the VB contralateral to the inflamed joint, and the ankle-bend test was performed. Ankle-bend scores in control animals were near the maximum and were rather constant throughout the entire experimental period, indicating severe nociception. The same was observed in 2 days MA rats injected with baclofen. In the 4 days MA group, the response to baclofen injection was inconsistent among different animals, whereas, in 14 days MA rats, baclofen caused clear antinociceptive effects. Additionally, a 0.5 microg dose of baclofen was tested in 14 days MA rats, but no effect was observed, whereas a 1.25 mug dose produced visible side effects. Baclofen injections that did not target the VB but reached neighboring nuclei were ineffective in reducing nociception. Data demonstrate that the activation of the GABAB receptors by baclofen in the VB of MA rats leads to a decrease of nociception. Moreover, the response depends on the time course of the disease, suggesting the occurrence of different excitatory states of thalamic VB neurons. In conclusion, GABAB receptors in the VB play an important role in chronic inflammatory pain processing.

Vitamin D2 dose required to rapidly increase 25OHD levels in osteoporotic women

Assessment of the effectiveness and safety of high daily 125 microg (5,000 IU) or 250 microg (10,000IU) doses of vitamin D(2) during 3 months, in rapidly obtaining adequate 25 hydroxyvitamin D (25OHD) levels. Longitudinal study. Postmenopausal osteopenic/osteoporotic women (n = 38) were studied during winter and spring. Median age (25-75th percentile) was 61.5 (57.00-66.25) years, and mean bone mineral density (BMD) was 0.902 (0.800-1.042)g/cm(2). Subjects were randomly divided into three groups: control group (n=13): no vitamin D(2), 125 mug/day (n=13) and 250 microg/day (n=12) of vitamin D(2) groups, all receiving 500 mg calcium/day. Serum calcium, phosphate, bone alkaline phosphatase (BAP), C-telopeptide (CTX), 25OHD, mid-molecule parathyroid hormone (mmPTH), daily urinary calcium and creatinine excretion were determined at baseline and monthly. For all subjects (n=38), the median baseline 25 hydroxyvitamin D (25OHD) level was 36.25 (27.5-48.12) nmol/l. After 3 months, 8% of the patients in the control group, 50% in the 125 microg/day group and 75% in the 250 microg/day group had 25OHD values above 85 nmol/l (34 ng/ml). Considering both vitamin D(2) groups together, mmPTH and BAP levels diminished significantly after 3 months (P<0.02), unlike those of CTX. Serum calcium remained within normal range during the follow-up. The oral dose of vitamin D(2) required to rapidly achieve adequate levels of 25OHD is seemingly much higher than the usual recommended vitamin D(3) dose (20 mug/day). During 3 months, 250 microg/day of vitamin D(2) most effectively raised 25OHD levels to 85 nmol/l in 75% of the postmenopausal osteopenic/osteoporotic women treated.