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1.
J Community Health ; 47(1): 53-62, 2022 02.
Article in English | MEDLINE | ID: mdl-34333719

ABSTRACT

Public acceptance of the HPV vaccine has not matched that of other common adolescent vaccines, and HPV vaccination rates remain below the Healthy People 2020 target of 80% compliance. The purpose of this study was to evaluate the capacity of nine pediatric clinics in a Federally Qualified Health Center organization to implement a systems-based intervention targeting office staff and providers using EHRs and a statewide immunization information system to increase HPV vaccination rates in girls and boys, ages 11 to 16 over a 16-month period. System changes included automated HPV prompts to staff, postcard reminders to parents when youths turned 11 or 12 years old, and monthly assessment of provider vaccination rates.During the intervention, 8960 patients (11-16 yo) were followed, with 48.8% girls (n = 4370) and 51.2% boys (n = 4590). For this study period, 80.5% of total patients received the first dose of the HPV vaccine and 47% received the second dose. For the first dose, 55.5% of 11 year old girls and 54.3% of 11 year old boys were vaccinated. For ages 12 to 16, first dose vaccination rates ranged from the lowest rate of 84.5% for 14 yo girls up to the highest rate of 90.5% for 13 yo boys. Logistic regression showed age was highly significantly associated with first dose completion (OR 1.565, 95% CI 1.501, 1.631) while males did not have a significant association with first dose completion compared to females. The intervention increased overall counts of first and second HPV vaccination rates.


Subject(s)
Alphapapillomavirus , Papillomavirus Infections , Papillomavirus Vaccines , Adolescent , Child , Female , Humans , Immunization , Information Systems , Male , Papillomavirus Infections/prevention & control , Papillomavirus Vaccines/therapeutic use , Vaccination
2.
Blood ; 129(13): 1823-1830, 2017 03 30.
Article in English | MEDLINE | ID: mdl-28188131

ABSTRACT

Patients with myelofibrosis (MF) often develop anemia and frequently become dependent on red blood cell transfusions. Results from a phase 2 study for the treatment of MF with the Janus kinase 1/2 (JAK1/2) inhibitor momelotinib (MMB) demonstrated that MMB treatment ameliorated anemia, which was unexpected for a JAK1/2 inhibitor, because erythropoietin-mediated JAK2 signaling is essential for erythropoiesis. Using a rat model of anemia of chronic disease, we demonstrated that MMB treatment can normalize hemoglobin and red blood cell numbers. We found that this positive effect is driven by direct inhibition of the bone morphogenic protein receptor kinase activin A receptor, type I (ACVR1), and the subsequent reduction of hepatocyte hepcidin production. Of note, ruxolitinib, a JAK1/2 inhibitor approved for the treatment of MF, had no inhibitory activity on this pathway. Further, we demonstrated the effect of MMB is not mediated by direct inhibition of JAK2-mediated ferroportin (FPN1) degradation, because neither MMB treatment nor myeloid-specific deletion of JAK2 affected FPN1 expression. Our data support the hypothesis that the improvement of inflammatory anemia by MMB results from inhibition of ACVR1-mediated hepcidin expression in the liver, which leads to increased mobilization of sequestered iron from cellular stores and subsequent stimulation of erythropoiesis.


Subject(s)
Anemia/drug therapy , Benzamides/therapeutic use , Bone Morphogenetic Protein Receptors, Type I/antagonists & inhibitors , Hepcidins/biosynthesis , Pyrimidines/therapeutic use , Activin Receptors, Type I/antagonists & inhibitors , Animals , Benzamides/pharmacology , Chronic Disease , Hepatocytes/metabolism , Iron/metabolism , Primary Myelofibrosis/complications , Pyrimidines/pharmacology , Rats
3.
Invest New Drugs ; 31(1): 126-35, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22451157

ABSTRACT

PURPOSE: CYT997 is a novel microtubule inhibitor and vascular disrupting agent. This phase I trial examined the safety, tolerability, pharmacokinetics and vascular-disrupting effects of orally-administered CYT997. EXPERIMENTAL DESIGN: We performed a phase I accelerated dose-escalation study of CYT997 given orally once every 2 to 3 weeks in patients with advanced solid tumours. Vascular disruption was assessed by measurement of plasma von Willebrand factor (vWF) levels and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). RESULTS: A total of 56 doses were administered to 21 patients over 8 dose levels (15-164 mg/m(2)). Grade 3 fatigue and grade 3 hypoxia were dose limiting. Oral bioavailability was observed with approximate linear pharmacokinetics over the 11-fold dose range. At doses of 84 mg/m(2) and above, plasma vWF levels increased above baseline and DCE-MRI scans showed reductions in tumour K(trans) in some patients. CONCLUSIONS: CYT997 is orally bioavailable. The 118 mg/m(2) dose level should be used to guide dosing in future studies.


Subject(s)
Antineoplastic Agents/administration & dosage , Cytotoxins/administration & dosage , Neoplasms/drug therapy , Pyridines/administration & dosage , Pyrimidines/administration & dosage , Tubulin Modulators/administration & dosage , Administration, Oral , Aged , Antineoplastic Agents/adverse effects , Antineoplastic Agents/pharmacokinetics , Biological Availability , Cytotoxins/adverse effects , Cytotoxins/pharmacokinetics , Female , Humans , Male , Middle Aged , Neoplasms/blood , Pyridines/adverse effects , Pyridines/pharmacokinetics , Pyrimidines/adverse effects , Pyrimidines/pharmacokinetics , Tubulin Modulators/adverse effects , Tubulin Modulators/pharmacokinetics
4.
J Pharmacol Exp Ther ; 339(3): 799-806, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21917561

ABSTRACT

The orally active microtubule-disrupting agent (S)-1-ethyl-3-(2-methoxy-4-(5-methyl-4-((1-(pyridin-3-yl)butyl)amino)pyrimidin-2-yl)phenyl)urea (CYT997), reported previously by us (Bioorg Med Chem Lett 19:4639-4642, 2009; Mol Cancer Ther 8:3036-3045, 2009), is potently cytotoxic to a variety of cancer cell lines in vitro and shows antitumor activity in vivo. In addition to its cytotoxic activity, CYT997 possesses antivascular effects on tumor vasculature. To further characterize the vascular disrupting activity of CYT997 in terms of dose and temporal effects, we studied the activity of the compound on endothelial cells in vitro and on tumor blood flow in vivo by using a variety of techniques. In vitro, CYT997 is shown to potently inhibit the proliferation of vascular endothelial growth factor-stimulated human umbilical vein endothelial cells (IC(50) 3.7 ± 1.8 nM) and cause significant morphological changes at 100 nM, including membrane blebbing. Using the method of corrosion casting visualized with scanning electron microscopy, a single dose of CYT997 (7.5 mg/kg i.p.) in a metastatic cancer model was shown to cause destruction of tumor microvasculature in metastatic lesions. Furthermore, repeat dosing of CYT997 at 10 mg/kg and above (intraperitoneally, b.i.d.) was shown to effectively inhibit development of liver metastases. The time and dose dependence of the antivascular effects were studied in a DLD-1 colon adenocarcinoma xenograft model using the fluorescent dye Hoechst 33342. CYT997 demonstrated rapid and dose-dependent vascular shutdown, which persists for more than 24 h after a single oral dose. Together, the data demonstrate that CYT997 possesses potent antivascular activity and support continuing development of this promising compound.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Antineoplastic Agents/pharmacology , Colonic Neoplasms/blood supply , Neovascularization, Pathologic/drug therapy , Pyridines/pharmacology , Pyrimidines/pharmacology , Tubulin Modulators/pharmacology , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Animals , Cell Line, Tumor , Cell Proliferation/drug effects , Colonic Neoplasms/drug therapy , Colonic Neoplasms/pathology , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Human Umbilical Vein Endothelial Cells , Humans , Liver Neoplasms/drug therapy , Liver Neoplasms/pathology , Liver Neoplasms/secondary , Male , Mice , Mice, Nude , Time Factors , Xenograft Model Antitumor Assays
5.
Invest New Drugs ; 29(2): 232-8, 2011 Apr.
Article in English | MEDLINE | ID: mdl-19907921

ABSTRACT

Multiple Myeloma (MM) is an incurable malignancy of mature plasma cells. Microtubule targeting agents (MTAs) are an established class of drug that include many conventional and some novel compounds. MTAs function by inhibiting the polymerisation or depolymerisation of microtubules (MTs) within the cell, disrupting various important cellular functions. We have investigated pre-clinically the novel tubulin polymerisation inhibitor CYT997 for the potential treatment of MM. Here we demonstrate the promising anti-myeloma activity of CYT997 as evidenced by tubulin disruption, inhibition of growth and proliferation, cell cycle arrest and most importantly apoptosis of both human myeloma cell lines (HMCLs) and primary MM cells using nanomolar drug concentrations. CYT997 also synergises with bortezomib to produce more potent anti-MM activity. These in vitro observations were validated in vivo by the ability of CYT997 to significantly prolong survival in a murine model of aggressive systemic myelomatosis. These findings provide a basis for continuing pre-clinical and clinical investigations into the anti-MM effects of CYT997.


Subject(s)
Apoptosis/drug effects , Multiple Myeloma/pathology , Pyridines/pharmacology , Pyrimidines/pharmacology , Animals , Boronic Acids/pharmacology , Bortezomib , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Screening Assays, Antitumor , Drug Synergism , Fluorescent Antibody Technique , G2 Phase/drug effects , Humans , Mice , Mitosis/drug effects , Polymerization/drug effects , Pyrazines/pharmacology , Survival Analysis , Time Factors , Tubulin/metabolism
6.
J Pharm Pharmacol ; 60(2): 171-8, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18237464

ABSTRACT

The plasma pharmacokinetics and brain uptake of the novel neuroprotective agent AM-36 (1-(2-(4-chlorophenyl)-2-hydroxy)ethyl-4-(3,5-bis-(1,1dimethylethyl)-4-hydroxyphenyl) methylpiperazine) were assessed over 72 h following i.v. administration to male Sprague-Dawley rats. At nominal i.v. doses of 0.2, 1 and 3mg kg(-1), AM-36 exhibited an extremely large volume of distribution (18.2-24.6 L kg(-1)) and a long terminal elimination half-life, ranging from 25.2 to 37.7 h. Over this dose range, AM-36 exhibited linear pharmacokinetics, with no apparent change in clearance, volume of distribution or dose-normalised area under the plasma concentration - time curve. AM-36 was very highly bound to plasma proteins (> 99.6%); however, this did not appear to affect the ability of AM-36 to permeate the blood-brain barrier. Following a single i.v. dose of AM-36 at 3mg kg(-1) to rats, brain concentrations were detected for up to 72 h, and the brain-to-plasma ratios were high at all time points (ranging from 8.2 at 5 min post-dose to 0.9 at 72 h post-dose). The very high brain uptake of AM-36 supports previous in-vivo efficacy studies demonstrating the neuroprotective effects of this compound when administered to rats with middle cerebral artery occlusion.


Subject(s)
Blood-Brain Barrier/metabolism , Brain/metabolism , Neuroprotective Agents/pharmacokinetics , Piperazines/pharmacokinetics , Animals , Area Under Curve , Dose-Response Relationship, Drug , Half-Life , Injections, Intravenous , Male , Neuroprotective Agents/administration & dosage , Piperazines/administration & dosage , Protein Binding , Rats , Rats, Sprague-Dawley , Time Factors , Tissue Distribution
7.
Nat Med ; 11(5): 507-14, 2005 May.
Article in English | MEDLINE | ID: mdl-15834429

ABSTRACT

Platelet activation at sites of vascular injury is essential for the arrest of bleeding; however, excessive platelet accumulation at regions of atherosclerotic plaque rupture can result in the development of arterial thrombi, precipitating diseases such as acute myocardial infarction and ischemic stroke. Rheological disturbances (high shear stress) have an important role in promoting arterial thrombosis by enhancing the adhesive and signaling function of platelet integrin alpha(IIb)beta(3) (GPIIb-IIIa). In this study we have defined a key role for the Type Ia phosphoinositide 3-kinase (PI3K) p110beta isoform in regulating the formation and stability of integrin alpha(IIb)beta(3) adhesion bonds, necessary for shear activation of platelets. Isoform-selective PI3K p110beta inhibitors have been developed which prevent formation of stable integrin alpha(IIb)beta(3) adhesion contacts, leading to defective platelet thrombus formation. In vivo, these inhibitors eliminate occlusive thrombus formation but do not prolong bleeding time. These studies define PI3K p110beta as an important new target for antithrombotic therapy.


Subject(s)
Arteries/pathology , Phosphatidylinositol 3-Kinases/metabolism , Platelet Adhesiveness/physiology , Platelet Glycoprotein GPIIb-IIIa Complex/metabolism , Signal Transduction/physiology , Thrombosis/metabolism , Animals , Bleeding Time , Blood Platelets/metabolism , Flow Cytometry , Isoenzymes/metabolism , Mice , Mice, Knockout , Phosphoinositide-3 Kinase Inhibitors , Rheology , Serotonin/metabolism , Thrombosis/pathology , rap GTP-Binding Proteins/metabolism
8.
Pain ; 62(1): 51-60, 1995 Jul.
Article in English | MEDLINE | ID: mdl-7478708

ABSTRACT

Antinociceptive tolerance to morphine (MOR) was induced in groups of Sprague-Dawley rats receiving continuous intravenous infusions of morphine sulphate administered by 3 different MOR dosing regimes. At appropriate intervals throughout each infusion period, antinociceptive testing was performed using the tail-flick latency test and blood samples were collected. Groups of saline (SAL)-infused control rats also underwent antinociceptive testing and blood sample collection. Complete antinociceptive tolerance developed during each MOR infusion period and was characterized by a marked decline in the degree of antinociception from values greater than 90% of the maximum possible effect (%MPE) to pre-dosing baseline values. By contrast, %MPE values in SAL-infused control animals and in sham-operated rats were not significantly different from pre-dosing values throughout the infusion period, indicating that the experimental procedures themselves did not contribute to the development of antinociceptive tolerance to MOR. In addition, the rate of MOR tolerance development was inversely proportional to the MOR infusion rate. A very significant inverse relationship was observed between the mean degree of antinociception (%MPE) and the mean plasma molar concentration ratio, [morphine-3-glucuronide]/[MOR], for each of the 3 MOR dosing regimes and for the cumulated data. This relationship showed that near-maximum antinociception was attainable at ratio values less than approximately 0.50, whilst at ratio values above approximately 1.5, little or no antinociception was observed. Although %MPE was highly inversely correlated with the mean plasma morphine-3-glucuronide (M3G) concentrations for rats receiving regimes A and B, this was not the case for rats receiving regime C where antinociceptive tolerance was partially reversed by an increase in the morphine infusion rate part-way through the infusion period. In addition, a poor relationship was observed between %MPE and the mean plasma MOR concentration, possibly due to the confounding presence of M3G in all samples. Thus, we may conclude from this study in Sprague-Dawley rats that irrespective of the rate of antinociceptive tolerance development, the level of antinociception achievable appears to be highly inversely correlated with the mean [M3G]/[MOR] plasma molar concentration ratio and poorly correlated with the plasma MOR concentration, consistent with the notion that it is perhaps the balance between the excitatory effects of M3G and the inhibitory effects of MOR at the functional level which is the important determinant. Further research is required in carefully conducted studies in cancer patients to evaluate the possible contribution of the MOR metabolites, M3G and morphine-6-glucuronide (MbG), to increasing dosing requirements of MOR.(ABSTRACT TRUNCATED AT 400 WORDS)


Subject(s)
Analgesics, Opioid/metabolism , Analgesics, Opioid/pharmacology , Analgesics/pharmacology , Morphine Derivatives/metabolism , Morphine/metabolism , Morphine/pharmacology , Analgesics, Opioid/blood , Animals , Chromatography, High Pressure Liquid , Dose-Response Relationship, Drug , Drug Tolerance , Male , Morphine/blood , Morphine Derivatives/blood , Pain Measurement , Rats , Rats, Sprague-Dawley
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