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1.
Chemistry ; 29(40): e202300645, 2023 Jul 14.
Article in English | MEDLINE | ID: mdl-37134303

ABSTRACT

Carbazole- and fluorene-substituted benzidine blocks have been functionalized with two different solubilizing pendant groups, in order to enhance the material's solubility in greener solvents. Preserving the optical and electrochemical properties, the aromatic function and substitution showed an important influence on the solvent affinity, achieving concentrations up to 150 mg/mL in o-xylenes for the glycol-containing materials and decent solubility in alcohols for the compounds functionalized with ionic chains. The latter solution proved to be ideal for the preparation of luminescence slot-die coating film on top of flexible-substrates up to 33 cm×2 cm. As a proof of concept, the materials have been implemented in different organic electronic devices, highlighting the low turn-on voltage (4 V) presented by organic light-emitting diodes (OLEDs), which is comparable with vacuum-processed devices. A structure-solubility relationship and a synthetic strategy are disentangled in this manuscript to tailor organic semiconductors and adapt their solubility towards the desired solvent and application.

2.
Nat Commun ; 14(1): 97, 2023 01 06.
Article in English | MEDLINE | ID: mdl-36609611

ABSTRACT

Richter's Transformation (RT) is a poorly understood and fatal progression of chronic lymphocytic leukemia (CLL) manifesting histologically as diffuse large B-cell lymphoma. Protein arginine methyltransferase 5 (PRMT5) is implicated in lymphomagenesis, but its role in CLL or RT progression is unknown. We demonstrate herein that tumors uniformly overexpress PRMT5 in patients with progression to RT. Furthermore, mice with B-specific overexpression of hPRMT5 develop a B-lymphoid expansion with increased risk of death, and Eµ-PRMT5/TCL1 double transgenic mice develop a highly aggressive disease with transformation that histologically resembles RT; where large-scale transcriptional profiling identifies oncogenic pathways mediating PRMT5-driven disease progression. Lastly, we report the development of a SAM-competitive PRMT5 inhibitor, PRT382, with exclusive selectivity and optimal in vitro and in vivo activity compared to available PRMT5 inhibitors. Taken together, the discovery that PRMT5 drives oncogenic pathways promoting RT provides a compelling rationale for clinical investigation of PRMT5 inhibitors such as PRT382 in aggressive CLL/RT cases.


Subject(s)
Leukemia, Lymphocytic, Chronic, B-Cell , Lymphoma, Large B-Cell, Diffuse , Animals , Mice , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Lymphoma, Large B-Cell, Diffuse/pathology
3.
Leukemia ; 37(2): 326-338, 2023 02.
Article in English | MEDLINE | ID: mdl-36376377

ABSTRACT

Chronic lymphocytic leukemia (CLL) is effectively treated with targeted therapies including Bruton tyrosine kinase inhibitors and BCL2 antagonists. When these become ineffective, treatment options are limited. Positive transcription elongation factor complex (P-TEFb), a heterodimeric protein complex composed of cyclin dependent kinase 9 (CDK9) and cyclin T1, functions to regulate short half-life transcripts by phosphorylation of RNA Polymerase II (POLII). These transcripts are frequently dysregulated in hematologic malignancies; however, therapies targeting inhibition of P-TEFb have not yet achieved approval for cancer treatment. VIP152 kinome profiling revealed CDK9 as the main enzyme inhibited at 100 nM, with over a 10-fold increase in potency compared with other inhibitors currently in development for this target. VIP152 induced cell death in CLL cell lines and primary patient samples. Transcriptome analysis revealed inhibition of RNA degradation through the AU-Rich Element (ARE) dysregulation. Mechanistically, VIP152 inhibits the assembly of P-TEFb onto the transcription machinery and disturbs binding partners. Finally, immune competent mice engrafted with CLL-like cells of Eµ-MTCP1 over-expressing mice and treated with VIP152 demonstrated reduced disease burden and improvement in overall survival compared to vehicle-treated mice. These data suggest that VIP152 is a highly selective inhibitor of CDK9 that represents an attractive new therapy for CLL.


Subject(s)
Leukemia, Lymphocytic, Chronic, B-Cell , Positive Transcriptional Elongation Factor B , Animals , Mice , Positive Transcriptional Elongation Factor B/metabolism , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Leukemia, Lymphocytic, Chronic, B-Cell/metabolism , Cyclin-Dependent Kinase 9 , Cyclin T/metabolism , Phosphorylation , Cell Nucleus/metabolism , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use
4.
Cancers (Basel) ; 14(16)2022 Aug 14.
Article in English | MEDLINE | ID: mdl-36010919

ABSTRACT

Currently, adaptive strategies require time- and resource-intensive manual structure corrections. This study compares different strategies: optimization without manual structure correction, adaptation with physician-drawn structures, and no adaptation. Strategies were compared for 16 patients with pancreas, liver, and head and neck (HN) cancer with 1-5 repeated images during treatment: 'reference adaptation', with structures drawn by a physician; 'single-DIR adaptation', using a single set of deformably propagated structures; 'multi-DIR adaptation', using robust planning with multiple deformed structure sets; 'conservative adaptation', using the intersection and union of all deformed structures; 'probabilistic adaptation', using the probability of a voxel belonging to the structure in the optimization weight; and 'no adaptation'. Plans were evaluated using reference structures and compared using a scoring system. The reference adaptation with physician-drawn structures performed best, and no adaptation performed the worst. For pancreas and liver patients, adaptation with a single DIR improved the plan quality over no adaptation. For HN patients, integrating structure uncertainties brought an additional benefit. If resources for manual structure corrections would prevent online adaptation, manual correction could be replaced by a fast 'plausibility check', and plans could be adapted with correction-free adaptation strategies. Including structure uncertainties in the optimization has the potential to make online adaptation more automatable.

5.
Nat Commun ; 12(1): 6338, 2021 11 03.
Article in English | MEDLINE | ID: mdl-34732719

ABSTRACT

Rare, recurrent balanced translocations occur in a variety of cancers but are often not functionally interrogated. Balanced translocations with the immunoglobulin heavy chain locus (IGH; 14q32) in chronic lymphocytic leukemia (CLL) are infrequent but have led to the discovery of pathogenic genes including CCND1, BCL2, and BCL3. Following identification of a t(X;14)(q28;q32) translocation that placed the mature T cell proliferation 1 gene (MTCP1) adjacent to the immunoglobulin locus in a CLL patient, we hypothesized that this gene may have previously unrecognized importance. Indeed, here we report overexpression of human MTCP1 restricted to the B cell compartment in mice produces a clonal CD5+/CD19+ leukemia recapitulating the major characteristics of human CLL and demonstrates favorable response to therapeutic intervention with ibrutinib. We reinforce the importance of genetic interrogation of rare, recurrent balanced translocations to identify cancer driving genes via the story of MTCP1 as a contributor to CLL pathogenesis.


Subject(s)
Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/metabolism , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/metabolism , Translocation, Genetic , Adult , Aged , Aged, 80 and over , Animals , B-Cell Lymphoma 3 Protein , Cyclin D1 , Female , Gene Expression Regulation , Genes, Immunoglobulin Heavy Chain , Humans , Immunoglobulin Heavy Chains/genetics , Male , Mice , Mice, Inbred C57BL , Middle Aged , Oncogenes/genetics , Proto-Oncogene Proteins c-bcl-2
6.
Am J Hematol ; 95(12): 1457-1465, 2020 12.
Article in English | MEDLINE | ID: mdl-32777116

ABSTRACT

Patients with relapsed/refractory (R/R) acute myeloid leukemia (AML) have poor outcomes and hematopoietic cell transplantation (HCT) is the only curative treatment. New targeted therapies improved survival in select patients with specific mutations, however management of patients without these molecular alterations is an unmet need. We conducted a phase one study of lenalidomide in combination with cytarabine/idarubicin salvage chemotherapy in patients with R/R AML and high-risk myelodysplastic syndromes. A total of 33 patients were enrolled in the study (30 AML, 3 MDS), and treated at three dose levels with 3 + 3 design. Dose-limiting toxicity (DLT) was seen in eight patients, including four hematologic DLTs. The most commonly observed non-hematologic serious adverse events were febrile neutropenia, rash, sepsis and renal injury. Dose level -1, consisting of 25 mg/d lenalidomide D1-21, 1 g/m2 cytarabine D5-8, and 8 mg/m2 idarubicin D5-7 was determined to be the maximum tolerated dose. Note, 15/33 (45%) of patients were able to receive pre-planned 21 days of lenalidomide. Overall, 18 patients achieved complete remission (CR) (n = 14) or CR with incomplete count recovery (CRi) (n = 4) with total CR/CRi rate of 56%. The 1-year and 2-year overall survival (OS) were 24% and 10%, respectively. Among responders, 10/18 underwent allogeneic HCT and had a 1-year OS of 40%. There was no molecular pattern associated with response. These data demonstrate that the combination had clinical activity in R/R AML. This regimen should be further investigated for patients who relapsed after HCT, and as a bridge therapy to HCT. (ClinicalTrials.gov identifier: NCT01132586).


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Leukemia, Myeloid, Acute , Myelodysplastic Syndromes , Adolescent , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Cytarabine/administration & dosage , Cytarabine/adverse effects , Disease-Free Survival , Female , Humans , Idarubicin/administration & dosage , Idarubicin/adverse effects , Lenalidomide/administration & dosage , Lenalidomide/adverse effects , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/mortality , Male , Middle Aged , Myelodysplastic Syndromes/drug therapy , Myelodysplastic Syndromes/mortality , Survival Rate
7.
Sci Adv ; 6(33): eabb9110, 2020 08.
Article in English | MEDLINE | ID: mdl-32851187

ABSTRACT

The biophysical and molecular mechanisms that enable animals to detect magnetic fields are unknown. It has been proposed that birds have a light-dependent magnetic compass that relies on the formation of radical pairs within cryptochrome molecules. Using spectroscopic methods, we show that pigeon cryptochrome clCRY4 is photoreduced efficiently and forms long-lived spin-correlated radical pairs via a tetrad of tryptophan residues. We report that clCRY4 is broadly and stably expressed within the retina but enriched at synapses in the outer plexiform layer in a repetitive manner. A proteomic survey for retinal-specific clCRY4 interactors identified molecules that are involved in receptor signaling, including glutamate receptor-interacting protein 2, which colocalizes with clCRY4. Our data support a model whereby clCRY4 acts as an ultraviolet-blue photoreceptor and/or a light-dependent magnetosensor by modulating glutamatergic synapses between horizontal cells and cones.

8.
J Clin Med ; 9(7)2020 Jul 17.
Article in English | MEDLINE | ID: mdl-32708954

ABSTRACT

Sickle-cell disease (SCD) is a debilitating hematological disorder with very few approved treatment options. Therapeutic reactivation of fetal hemoglobin (HbF) is one of the most pursued methods for ameliorating the systemic manifestations of SCD. Despite this, very few pharmacological agents have advanced to clinical trials or marketing for use. In this study, we report the development of an HbF in situ intracellular immunoblot assay coupled to a high-throughput drug screen to identify Food and Drug Administration (FDA) approved drugs that can be repurposed clinically for treatment of SCD. Using this assay we evaluated the National Institute of Health (NIH) Clinical Collection (NCC), a publicly available library of 725 small molecules, and found nine candidates that can significantly re-express HbF in erythroid cell lines as well as primary erythroblasts derived from SCD patients. Furthermore, we show the strong effects on HbF expression of these candidates to occur with minimal cytotoxicity in 7 of the 9 drugs. Given these data and their proven history of use for other indications, we hypothesize that several of these candidate drugs warrant further investigation for use in SCD.

9.
Sci Rep ; 10(1): 2153, 2020 02 07.
Article in English | MEDLINE | ID: mdl-32034234

ABSTRACT

Hematopoietic stem cells (HSCs) are functionally and genetically diverse and this diversity decreases with age and disease. Numerous systems have been developed to quantify HSC diversity by genetic barcoding, but no framework has been established to empirically validate barcode sequences. Here we have developed an analytical framework, Selection of informative Amplicon Barcodes from Experimental Replicates (SABER), that identifies barcodes that are unique among a large set of experimental replicates. Amplicon barcodes were sequenced from the blood of 56 adult zebrafish divided into training and validation sets. Informative barcodes were identified and samples with a high fraction of informative barcodes were chosen by bootstrapping. There were 4.2 ± 1.8 barcoded HSC clones per sample in the training set and 3.5 ± 2.1 in the validation set (p = 0.3). SABER reproducibly quantifies functional HSCs and can accommodate a wide range of experimental group sizes. Future large-scale studies aiming to understand the mechanisms of HSC clonal evolution will benefit from this new approach to identifying informative amplicon barcodes.


Subject(s)
Clonal Evolution , Genotyping Techniques/methods , Hematopoiesis , Hematopoietic Stem Cells/metabolism , Mutation , Algorithms , Animals , Genotyping Techniques/standards , Hematopoietic Stem Cells/cytology , Sequence Analysis, DNA/methods , Sequence Analysis, DNA/standards , Zebrafish
10.
Sci Rep ; 10(1): 915, 2020 01 22.
Article in English | MEDLINE | ID: mdl-31969617

ABSTRACT

The transcription factor ZENK is an immediate early gene that has been employed as a surrogate marker to map neuronal activity in the brain. It has been used in a wide variety of species, however, commercially available antibodies have limited immunoreactivity in birds. To address this issue we generated a new mouse monoclonal antibody, 7B7-A3, raised against ZENK from the rock pigeon (Columba livia). We show that 7B7-A3 labels clZENK in both immunoblots and histological stainings with high sensitivity and selectivity for its target. Using a sound stimulation paradigm we demonstrate that 7B7-A3 can detect activity-dependent ZENK expression at key stations of the central auditory pathway of the pigeon. Finally, we compare staining efficiency across three avian species and confirm that 7B7-A3 is compatible with immunohistochemical detection of ZENK in the rock pigeon, zebra finch, and domestic chicken. Taken together, 7B7-A3 represents a useful tool for the avian neuroscience community to map functional activity in the brain.


Subject(s)
Antibodies, Monoclonal, Murine-Derived , Auditory Pathways/physiology , Birds/immunology , Birds/physiology , Brain/cytology , Brain/physiology , Early Growth Response Protein 1/immunology , Neurons/physiology , Animals , Antibodies, Monoclonal, Murine-Derived/metabolism , Columbidae , Mice
11.
J Public Health Res ; 8(3): 1407, 2019 Dec 04.
Article in English | MEDLINE | ID: mdl-31857987

ABSTRACT

There is an increasing body of evidence suggesting that transmission of respiratory viruses occurs through the inhalation of virus-laden particles. Our study describes the use of an aerosol sampling system to monitor the prevalence of airborne viruses in a hospital setting. Using SKC AirCheck Touch pumps, with National Institute for Occupational Safety and Health (NIOSH) bioaerosol samplers and SKC filter cassette blanks, 28 aerosol samples were collected in a hospital ward in Singapore. Following DNA/RNA extraction, real-time RT-PCR/PCR was used for the detection of influenza A, B and D viruses, coronaviruses, enteroviruses, and adenoviruses. Airborne virus was detected in nine (32%) of 28 samples. Among the nine positive samples, eight were PCR-positive for adenovirus and one for influenza A virus. Our data suggest that bioaerosol sampling could be valuable in monitoring for airborne respiratory viruses in clinical environments to better understand the risk of infection during a hospital visit.

12.
Curr Biol ; 29(23): 4052-4059.e4, 2019 12 02.
Article in English | MEDLINE | ID: mdl-31735675

ABSTRACT

A diverse array of vertebrate species employs the Earth's magnetic field to assist navigation. Despite compelling behavioral evidence that a magnetic sense exists, the location of the primary sensory cells and the underlying molecular mechanisms remain unknown [1]. To date, most research has focused on a light-dependent radical-pair-based concept and a system that is proposed to rely on biogenic magnetite (Fe3O4) [2, 3]. Here, we explore an overlooked hypothesis that predicts that animals detect magnetic fields by electromagnetic induction within the semicircular canals of the inner ear [4]. Employing an assay that relies on the neuronal activity marker C-FOS, we confirm that magnetic exposure results in activation of the caudal vestibular nuclei in pigeons that is independent of light [5]. We show experimentally and by physical calculations that magnetic stimulation can induce electric fields in the pigeon semicircular canals that are within the physiological range of known electroreceptive systems. Drawing on this finding, we report the presence of a splice isoform of a voltage-gated calcium channel (CaV1.3) in the pigeon inner ear that has been shown to mediate electroreception in skates and sharks [6]. We propose that pigeons detect magnetic fields by electromagnetic induction within the semicircular canals that is dependent on the presence of apically located voltage-gated cation channels in a population of electrosensory hair cells.


Subject(s)
Columbidae/physiology , Ear, Inner/physiology , Magnetic Fields , Sensation , Animals
13.
Mol Cell ; 67(4): 566-578.e10, 2017 Aug 17.
Article in English | MEDLINE | ID: mdl-28803781

ABSTRACT

50 years ago, Vincent Allfrey and colleagues discovered that lymphocyte activation triggers massive acetylation of chromatin. However, the molecular mechanisms driving epigenetic accessibility are still unknown. We here show that stimulated lymphocytes decondense chromatin by three differentially regulated steps. First, chromatin is repositioned away from the nuclear periphery in response to global acetylation. Second, histone nanodomain clusters decompact into mononucleosome fibers through a mechanism that requires Myc and continual energy input. Single-molecule imaging shows that this step lowers transcription factor residence time and non-specific collisions during sampling for DNA targets. Third, chromatin interactions shift from long range to predominantly short range, and CTCF-mediated loops and contact domains double in numbers. This architectural change facilitates cognate promoter-enhancer contacts and also requires Myc and continual ATP production. Our results thus define the nature and transcriptional impact of chromatin decondensation and reveal an unexpected role for Myc in the establishment of nuclear topology in mammalian cells.


Subject(s)
B-Lymphocytes/metabolism , Cell Cycle , Cell Nucleus/metabolism , Chromatin Assembly and Disassembly , Chromatin/metabolism , Histones/metabolism , Lymphocyte Activation , Proto-Oncogene Proteins c-myc/metabolism , Acetyl Coenzyme A/metabolism , Acetylation , Adenosine Triphosphate/metabolism , Animals , B-Lymphocytes/immunology , Cell Line , Chromatin/chemistry , Chromatin/genetics , DNA Methylation , Epigenesis, Genetic , Genotype , Histones/chemistry , Immunity, Humoral , Methylation , Mice, Inbred C57BL , Mice, Knockout , Nucleic Acid Conformation , Phenotype , Protein Interaction Domains and Motifs , Protein Processing, Post-Translational , Proto-Oncogene Proteins c-myc/chemistry , Proto-Oncogene Proteins c-myc/genetics , Single Molecule Imaging , Structure-Activity Relationship , Time Factors , Transcription, Genetic
14.
PLoS One ; 9(2): e89922, 2014.
Article in English | MEDLINE | ID: mdl-24587126

ABSTRACT

IncP-1, IncP-7 and IncP-9 plasmids often carry genes encoding enzymes involved in the degradation of man-made and natural contaminants, thus contributing to bacterial survival in polluted environments. However, the lack of suitable molecular tools often limits the detection of these plasmids in the environment. In this study, PCR followed by Southern blot hybridization detected the presence of plasmid-specific sequences in total community (TC-) DNA or fosmid DNA from samples originating from different environments and geographic regions. A novel primer system targeting IncP-9 plasmids was developed and applied along with established primers for IncP-1 and IncP-7. Screening TC-DNA from biopurification systems (BPS) which are used on farms for the purification of pesticide-contaminated water revealed high abundances of IncP-1 plasmids belonging to different subgroups as well as IncP-7 and IncP-9. The novel IncP-9 primer-system targeting the rep gene of nine IncP-9 subgroups allowed the detection of a high diversity of IncP-9 plasmid specific sequences in environments with different sources of pollution. Thus polluted sites are "hot spots" of plasmids potentially carrying catabolic genes.


Subject(s)
DNA, Bacterial/genetics , Environmental Pollutants/chemistry , Genetic Variation , Plasmids/genetics , Animals , Base Sequence , Blotting, Southern , DNA Primers/genetics , Europe , Molecular Sequence Data , Polymerase Chain Reaction , Porifera/microbiology , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
15.
Cancer Chemother Pharmacol ; 71(6): 1635-43, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23636448

ABSTRACT

PURPOSE: The metabolism of pazopanib is primarily mediated by CYP3A4. The solubility of pazopanib is pH-dependent, and an elevated gastric pH may decrease its bioavailability. This study evaluated the effect of a potent CYP3A4 inhibitor, ketoconazole, and the proton pump inhibitor esomeprazole on the pharmacokinetics and safety of pazopanib and its metabolites. METHODS: In Arm A, patients received pazopanib 400 mg alone once daily for 7 days followed by pazopanib 400 mg plus ketoconazole 400 mg once daily for 5 days. In Arm B, patients received pazopanib 800 mg once daily for 7 days, followed by pazopanib 800 mg plus esomeprazole 40 mg once daily for 5 days, and then pazopanib alone on the last day. RESULTS: Arm A enrolled 21 patients. In the presence of ketoconazole, mean area under the plasma concentration-time curve 24 h post-dose (AUC(0-24)) and mean maximum observed concentration (C max) of pazopanib increased by 66 and 45 %, respectively; mean AUC(0-24) and C max for pazopanib metabolites were lower or remained unchanged. Arm B enrolled 13 patients. In the presence of esomeprazole, mean pazopanib AUC(0-24) and C max decreased by 40 and 42 %, respectively; mean values of those parameters for metabolites of pazopanib also decreased. CONCLUSIONS: Concomitant use of pazopanib with a strong CYP3A4 inhibitor should be avoided. If coadministration is necessary, pazopanib should be reduced to 400 mg. Concomitant use of pazopanib and proton pump inhibitors should also be avoided. Alternative dosing regimens that do not increase gastric pH at the time of pazopanib dosing should be considered.


Subject(s)
Angiogenesis Inhibitors/pharmacokinetics , Esomeprazole/pharmacology , Ketoconazole/pharmacology , Neoplasms/drug therapy , Proton Pump Inhibitors/pharmacology , Pyrimidines/pharmacokinetics , Sulfonamides/pharmacokinetics , Adult , Aged , Aged, 80 and over , Angiogenesis Inhibitors/administration & dosage , Angiogenesis Inhibitors/adverse effects , Angiogenesis Inhibitors/therapeutic use , Cytochrome P-450 CYP3A , Cytochrome P-450 CYP3A Inhibitors , Dose-Response Relationship, Drug , Drug Administration Schedule , Drug Interactions , Esomeprazole/administration & dosage , Esomeprazole/adverse effects , Female , Humans , Indazoles , Ketoconazole/administration & dosage , Ketoconazole/adverse effects , Male , Middle Aged , Neoplasms/metabolism , Proton Pump Inhibitors/administration & dosage , Proton Pump Inhibitors/adverse effects , Pyrimidines/administration & dosage , Pyrimidines/adverse effects , Pyrimidines/therapeutic use , Sulfonamides/administration & dosage , Sulfonamides/adverse effects , Sulfonamides/therapeutic use
16.
Technol Cancer Res Treat ; 9(3): 307-16, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20441241

ABSTRACT

This paper examines the uncertainty in estimating lung motion from external surrogates for lung cancer patients with regular and irregular breathing. 4DCT data sets were analyzed using a template matching algorithm to track the spatial movement of vessel bifurcations in 12 patients. The detected internal movement of features in 3D was retrospectively synchronized with the RPM surrogate signal, and the correlation index R(2) and the prediction error were computed. Patients were classified into two groups depending on the presence or not of irregularities in their breathing pattern. Peak-to-peak values of feature motion in the SI direction ranged from 0.8 mm (upper lung) to 25.3 mm (lower lung). Some patients exhibited large motion also in the latero-lateral (10.6 mm) and anterior-posterior (12.2 mm) directions. The median +/- quartile of R(2) in SI direction was 0.89 +/- 0.09. Prediction error values were up to 4.2 mm (95th percentile) with a maximum value of 4.9 mm. Statistical differences between regular and irregular breathers were found for R(2), while prediction error depended only on the range of motion. This study is relevant for image guided radiotherapy methods that rely on external surrogates to monitor motion.


Subject(s)
Four-Dimensional Computed Tomography/methods , Lung Neoplasms/diagnostic imaging , Lung/diagnostic imaging , Radiographic Image Interpretation, Computer-Assisted/methods , Respiration , Algorithms , Humans , Movement/physiology , Uncertainty
17.
Clin Colorectal Cancer ; 8(1): 29-37, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19203894

ABSTRACT

PURPOSE: This study evaluated safety, pharmacokinetics, and efficacy of 2 dose schedules and 2 infusion times of panitumumab in patients with advanced solid malignancies. PATIENTS AND METHODS: This phase I multicenter, open-label study sequentially enrolled patients with advanced solid tumors refractory to standard therapy, or for which no standard therapy exists, to receive panitumumab 6 mg/kg every 2 weeks or 9 mg/kg every 3 weeks. Patients receiving panitumumab every 2 weeks received either all infusions over 60 minutes or a 60-minute infusion for the first dose followed by 30-minute infusions if the first infusion was well tolerated. Patients in the every-3-week cohort received 60-minute infusions. Safety outcomes included the incidence of adverse events and antipanitumumab antibody formation. Pharmacokinetic properties were determined. Efficacy endpoints included response rate and duration of response. RESULTS: Eighty-six patients were enrolled; 84 (98%) received panitumumab. Treatment-related adverse events occurred in 90% of patients. Safety profiles were similar between patients receiving 30-minute (n = 20) and 60-minute (n = 43) infusions every 2 weeks and patients receiving panitumumab every 3 weeks (n = 21). Panitumumab exposure at steady state increased dose proportionally, and peak serum concentrations were similar in patients receiving either 30- or 60-minute infusions every 2 weeks. Objective responses were seen in 4 patients (5%) with colon, rectal, esophageal, and bladder cancers. CONCLUSION: Similar drug exposures and safety profiles were observed in patients receiving panitumumab 6 mg/kg every 2 weeks with either 30- or 60-minute infusions and antitumor activity was seen in some patients. Exposure increased approximately dose proportionally at steady state.


Subject(s)
Antibodies, Monoclonal/administration & dosage , Antineoplastic Agents/administration & dosage , Neoplasms/drug therapy , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal/pharmacokinetics , Antineoplastic Agents/adverse effects , Antineoplastic Agents/pharmacokinetics , Dose-Response Relationship, Drug , Endpoint Determination , Female , Humans , Infusions, Intravenous , Male , Middle Aged , Panitumumab , Treatment Outcome
18.
Hand (N Y) ; 3(1): 13-6, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18780114

ABSTRACT

Rock climbing has become increasingly more popular in the USA over the past two decades. Accordingly, with increased participation comes an increase in climbing-related injuries. Rooks et al noted that three-quarters of elite and recreational climbers will suffer upper extremity injuries, approximately 60% involving the hand or wrist and 40% divided evenly between the shoulder and elbow. Most of these injures will be strains, microtrauma, and tendonitis; however, 30-50% represent trauma to the proximal interphalangeal region. The purpose of this study was to investigate the biomechanical properties of the A2 and A4 pulley and compare biomechanical properties among gender and digit. A specially designed materials testing machine, shown in the included figure, measured maximum breaking load, displacement and stiffness of the A2 and A4 pulleys of ten cadaveric hands using an S hook to apply a steady force until complete pulley rupture. The A2 and A4 biomechanical properties of breaking load, displacement, and stiffness did not significantly differ among the index, middle, ring, and little fingers. Additionally, there was no significant difference in A2 or A4 pulley biomechanics between male and female specimens. The A2 and A4 pulleys among differing digits and genders have similar biomechanical properties in regards to maximum breaking load, displacement, and stiffness.

19.
Anim Cogn ; 10(4): 407-14, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17345056

ABSTRACT

Three experiments were conducted to test whether a pair of tufted capuchin monkeys (Cebus apella) could generalize their ability to exchange tokens and tool objects with a human experimenter to similar exchanges with a conspecific partner. Monkeys were tested in side-by-side enclosures, one enclosure containing a tool-use apparatus and one or more token(s), and the other enclosure containing one or more tool object(s). The monkeys willingly transferred tokens and tools to a conspecific with little practice. Following a small amount of training, we also found that the monkeys would select situation-appropriate tokens to exchange for specific tools, but did not select appropriate tool objects in response to another monkey's token transfers. Implications regarding role reversal are discussed.


Subject(s)
Animal Communication , Association Learning , Cebus/psychology , Generalization, Psychological , Tool Use Behavior , Animals , Humans , Male
20.
J Comp Psychol ; 120(2): 163-6, 2006 May.
Article in English | MEDLINE | ID: mdl-16719595

ABSTRACT

Self-control is defined as forgoing immediate gratification to obtain a greater reward. Tool use may relate to self-control because both behaviors may require foresight and deliberate control over one's actions. The authors assessed 20 capuchin monkeys (Cebus apella) for the ability to delay gratification in a tool task. Subjects were given rod-shaped food items that could either be consumed immediately or be carried to an apparatus and used to extract a more preferred food. The authors found that some monkeys were able to exhibit self-control. Monkeys with relatively more tool use experience demonstrated the greatest levels of self-control. These results indicate that capuchins are capable of delaying gratification when a higher quality reinforcer is present and that tool experience can influence levels of self-control in this task.


Subject(s)
Psychomotor Performance , Self Efficacy , Age Factors , Animals , Cebus , Distance Perception , Female , Male , Reinforcement, Psychology , Reward
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