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1.
Sci Rep ; 11(1): 12634, 2021 06 16.
Article in English | MEDLINE | ID: mdl-34135350

ABSTRACT

The critically endangered African forest elephant (Loxodonta cyclotis) plays a vital role in maintaining the structure and composition of Afrotropical forests, but basic information is lacking regarding the drivers of elephant movement and behavior at landscape scales. We use GPS location data from 96 individuals throughout Gabon to determine how five movement behaviors vary at different scales, how they are influenced by anthropogenic and environmental covariates, and to assess evidence for behavioral syndromes-elephants which share suites of similar movement traits. Elephants show some evidence of behavioral syndromes along an 'idler' to 'explorer' axis-individuals that move more have larger home ranges and engage in more 'exploratory' movements. However, within these groups, forest elephants express remarkable inter-individual variation in movement behaviours. This variation highlights that no two elephants are the same and creates challenges for practitioners aiming to design conservation initiatives.


Subject(s)
Elephants/physiology , Movement/physiology , Animals , Behavior, Animal/physiology , Endangered Species , Female , Forests , Gabon , Male
2.
Radiat Oncol ; 13(1): 132, 2018 Jul 20.
Article in English | MEDLINE | ID: mdl-30029684

ABSTRACT

BACKGROUND: Melanoma brain metastases (MBM) often cause morbidity and mortality for stage IV melanoma patients. An ongoing randomised phase III trial (NCT01503827 - WBRT-Mel) evaluates the role of adjuvant whole brain radiotherapy (WBRT) following local treatment of MBM. Hippocampal avoidance during WBRT (HA-WBRT) has shown memory and neurocognitive function (NCF) preservation in the RTOG-0933 phase II study. This study assessed the quality assurance of HA-WBRT within the WBRT-Mel trial according to RTOG-0933 study criteria. METHODS: Hippocampal avoidance was allowed in approved centres with intensity-modulated radiotherapy capability. Patients treated by HA-WBRT were not randomized within the WBRT arm. The RTOG 0933 contouring Atlas was used to contour hippocampi. In the trial co-ordinating centre, patients were treated with volumetric modulated arc therapy using complementary arcs; similar techniques were used at other sites. Dosimetric data were extracted retrospectively and analysed in accordance with RTOG 0933 study constraints criteria. RESULTS: Among the 215 patients accrued to the WBRT-Mel study between April 2009 and September 2017, 107 were randomized to the WBRT arm, 22 were treated by HA-WBRT in 4 centers. Eighteen patients were treated in the same centre. The median age was 65 years. The commonest (91%) HA-WBRT schema was 30 Gy in 10 fractions. Prior to HA-WBRT, 10 patients had been treated by surgery alone, six by radiosurgery alone, four by surgery and radiosurgery and two exclusively by simultaneous integrated boost concurrent to HA-WBRT. Twenty patients were treated with intention to spare both hippocampi and two patients had MBM close to one hippocampus and were treated with intention to spare the contralateral hippocampus. According to RTOG-0933 study criteria, 18 patients (82%) were treated within constraints and four patients (18%) had unacceptable deviation in just one hippocampus. CONCLUSIONS: This dosimetric quality assurance study shows good compliance (82%) according to RTOG-0933 study dosimetric constraints. Indeed, all patients respected RTOG hippocampal avoidance constraints on at least one hippocampus. In the futureanalysis of the WBRT-Mel trial, the NCF of patients on the observation arm, WBRT arm and with HA-WBRT arm will be compared.


Subject(s)
Brain Neoplasms/radiotherapy , Cranial Irradiation/methods , Hippocampus/radiation effects , Melanoma/radiotherapy , Organ Sparing Treatments/methods , Quality Assurance, Health Care , Radiation Injuries/prevention & control , Radiotherapy, Intensity-Modulated/methods , Adult , Aged , Aged, 80 and over , Australia , Brain Neoplasms/secondary , Cranial Irradiation/standards , Dose Fractionation, Radiation , Female , Humans , Male , Melanoma/secondary , Middle Aged , Organ Sparing Treatments/standards , Organ Sparing Treatments/statistics & numerical data , Radiosurgery/methods , Radiosurgery/standards , Radiotherapy Planning, Computer-Assisted , Radiotherapy, Intensity-Modulated/standards , Retrospective Studies , Young Adult
3.
Metallomics ; 8(2): 260, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26847676

ABSTRACT

Correction for 'Enantiopure titanocene complexes--direct evidence for paraptosis in cancer cells' by Melchior Cini et al., Metallomics, 2016, DOI: 10.1039/c5mt00297d.

4.
Metallomics ; 8(3): 286-97, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26806372

ABSTRACT

Tolerated by normal tissues, anti-cancer therapies based on titanium compounds are limited by low efficacy/selectivity and lack of understanding of their mode(s) of action. In vitro antitumour activity and mode of cell death incurred by enantiopure TiCl2{η-C5H4CHEt(2-MeOPh)}2 (abbreviated Cp(R)2TiCl2) has been investigated. The in vitro anti-tumour activity of Cp(R)2TiCl2 is selective for cancer cells; in clonogenic assays, (S,S)-Cp(R)2TiCl2 was twice as effective at inhibiting colony formation than other stereoisomers after 24 h exposure. HPLC, MS and NMR techniques determined hydrolysis of Cp(R)2TiCl2; data strongly correlate with soluble [Cp(R)2Ti(OH)(OH2)](+) being the biological trigger. Treatment of cells with Cp(R)2TiCl2 provoked extensive cytoplasmic vacuolization, endoplasmic reticulum (ER) swelling and activation of MAPKinase signal transduction, consistent with ligand-induced paraptosis, type III cell death, which is morphologically distinct from, and independent of apoptosis. Indeed, distinct from cisplatin, Cp(R)2TiCl2 failed to perturb cell cycle dynamics, induce γH2AX foci or evoke apoptosis in MDA-MB-468 and HCT-116 cells.


Subject(s)
Apoptosis/drug effects , Organometallic Compounds/chemistry , Organometallic Compounds/pharmacology , Cell Cycle/drug effects , Cell Line, Tumor , Cisplatin/pharmacology , DNA Breaks, Double-Stranded/drug effects , Flow Cytometry , Histones/metabolism , Humans , Proton Magnetic Resonance Spectroscopy , Stereoisomerism
5.
Nucl Med Biol ; 42(10): 788-95, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26162582

ABSTRACT

INTRODUCTION: Despite radical treatment therapies, glioma continues to carry with it a uniformly poor prognosis. Patients diagnosed with WHO Grade IV glioma (glioblastomas; GBM) generally succumb within two years, even those with WHO Grade III anaplastic gliomas and WHO Grade II gliomas carry prognoses of 2-5 and 2 years, respectively. PET imaging with (18)F-FDOPA allows in vivo assessment of the metabolism of glioma relative to surrounding tissues. The high sensitivity of (18)F-DOPA imaging grants utility for a number of clinical applications. METHODS: A collection of published work about (18)F-FDOPA PET was made and a critical review was discussed and written. RESULTS: A number of research papers have been published demonstrating that in conjunction with MRI, (18)F-FDOPA PET provides greater sensitivity and specificity than these modalities in detection, grading, prognosis and validation of treatment success in both primary and recurrent gliomas. In further comparisons with (11)C-MET, (18)F-FLT, (18)F-FET and MRI, (18)F-FDOPA has shown similar or better efficacy. Recently synthesis cassettes have become available, making (18)F-FDOPA more accessible. CONCLUSIONS: According to the available data, (18)F-FDOPA PET is a viable radiotracer for imaging and treatment planning of gliomas. ADVANCES IN KNOWLEDGE AND IMPLICATION FOR PATIENT CARE: (18)F-FDOPA PET appears to be a viable radiopharmaceutical for the diagnosis and treatment planning of gliomas cases, improving on that of MRI and (18)F-FDG PET.


Subject(s)
Dihydroxyphenylalanine/analogs & derivatives , Glioma/diagnostic imaging , Positron-Emission Tomography/methods , Feasibility Studies , Glioma/pathology , Glioma/radiotherapy , Glioma/surgery , Humans , Neoplasm Grading , Radiotherapy Planning, Computer-Assisted
6.
Semin Nucl Med ; 45(2): 136-50, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25704386

ABSTRACT

There is significant interest in the development of improved image-guided therapy for neuro-oncology applications. Glioblastomas (GBM) in particular present a considerable challenge because of their pervasive nature, propensity for recurrence, and resistance to conventional therapies. MRI is routinely used as a guide for planning treatment strategies. However, this imaging modality is not able to provide images that clearly delineate tumor boundaries and affords only indirect information about key tumor pathophysiology. With the emergence of PET imaging with new oncology radiotracers, mapping of tumor infiltration and other important molecular events such as hypoxia is now feasible within the clinical setting. In particular, the importance of imaging hypoxia levels within the tumoral microenvironment is gathering interest, as hypoxia is known to play a central role in glioma pathogenesis and resistance to treatment. One of the hypoxia radiotracers known for its clinical utility is (18)F-fluoromisodazole ((18)F-FMISO). In this review, we highlight the typical causes of treatment failure in gliomas that may be linked to hypoxia and outline current methods for the detection of hypoxia. We also provide an overview of the growing body of studies focusing on the clinical translation of (18)F-FMISO PET imaging, strengthening the argument for the use of (18)F-FMISO hypoxia imaging to help optimize and guide treatment strategies for patients with glioblastoma.


Subject(s)
Glioma/diagnostic imaging , Glioma/pathology , Misonidazole/analogs & derivatives , Positron-Emission Tomography/methods , Translational Research, Biomedical/methods , Animals , Cell Hypoxia , Glioma/physiopathology , Glioma/therapy , Humans , Treatment Failure
7.
Med Oncol ; 31(4): 881, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24549982

ABSTRACT

The purpose of this study was to compare toxicity rates and types between obese and non-obese women during adjuvant chemotherapy for breast cancer, adjusting for regimen type and received dose. We conducted a retrospective cohort study of 537 women receiving chemotherapy, initially treated between 2007 and 2010 at two tertiary hospitals in Brisbane, Australia. Demographic, chemotherapy and toxicity data were extracted from patient charts and analyzed using multivariate logistic regression. Three hundred and seventy-four women were eligible for inclusion. Obese women (body mass index (BMI) > 30 kg/m(2); mean age 52.58 ± 9.49) were older than non-obese women (BMI ≤ 29.9 kg/m(2); mean age 50.19 ± 11.15, P = 0.05) and had more comorbidities (P < 0.01). After adjustment for potential confounders, obesity was not statistically related to chemotherapy-related admission risk (OR 1.27; 95 % CI 0.78-2.09) or febrile neutropenia risk (OR 0.56; 95% CI 0.28-1.21). However, obese women received chemotherapy with proportionally lower mean relative dose intensity than non-obese women (94 vs. 97% of reference dose, P = 0.03). Eighteen (15.8%) obese and zero non-obese women (P < 0.01) had their chemotherapy dose capped at an arbitrary body surface area. Compared with non-obese women, obese women receive different chemotherapy regimens and relatively lower chemotherapy doses. There was no significant evidence of increased toxicity among obese women with either full or adjusted chemotherapy doses. Full body surface areas-based dosing appears to be tolerated as well in obese as in lean women.


Subject(s)
Breast Neoplasms/complications , Breast Neoplasms/drug therapy , Chemotherapy, Adjuvant/adverse effects , Obesity/complications , Adult , Aged , Antineoplastic Agents/adverse effects , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Body Mass Index , Body Size , Body Surface Area , Cohort Studies , Cyclophosphamide/adverse effects , Docetaxel , Epirubicin/adverse effects , Female , Fluorouracil/adverse effects , Humans , Middle Aged , Multivariate Analysis , Odds Ratio , Retrospective Studies , Taxoids/adverse effects
8.
J Nanosci Nanotechnol ; 12(11): 8797-800, 2012 Nov.
Article in English | MEDLINE | ID: mdl-23421289

ABSTRACT

The hydrothermal synthesis (HS) of NiFe2O4 nanoparticles (NPs) has been investigated using a novel valve-assisted pressure autoclave. This approach has facilitated the rapid quenching of hydrothermal suspensions into liquid nitrogen, providing 'snapshots' representative of the near in situ physical state of the synthesis reaction products as a function of known temperature. The acquired samples were examined using complementary characterisation techniques of transmission electron microscopy and X-ray diffractometry (XRD). The HS of NiFe2O4 NPs (< 25 nm) at pH - 8 proceeded through the formation and dissolution of intermediate amorphous Fe(OH)3 and FeNi3Cl2(OH)8 x H2O sheets with increasing reaction temperature. The near in situ nature of the HS suspension resulted in the formation of NaCI by-product during drying in advance of XRD investigation, not during the HS process.


Subject(s)
Crystallization/methods , Ferric Compounds/chemistry , Metal Nanoparticles/chemistry , Metal Nanoparticles/ultrastructure , Nickel/chemistry , Hot Temperature , Hydrodynamics , Macromolecular Substances/chemistry , Materials Testing , Molecular Conformation , Particle Size , Surface Properties
9.
J Nanosci Nanotechnol ; 12(11): 8801-5, 2012 Nov.
Article in English | MEDLINE | ID: mdl-23421290

ABSTRACT

The hydrothermal synthesis (HS) of CoFe2O4 nanoparticles (NPs) has been investigated as a function of reaction temperature and pH, using complementary characterisation techniques of transmission electron microscopy and X-ray diffractometry. The HS of CoFe2O4 NPs (< 25 nm) at pH - 8 proceeded through the formation and dissolution of intermediate Fe(OH)3 and [FeCo3(OH)8]+ x [Cl- x H2O]- phases with increasing reaction temperature. In contrast, HS of CoFe2O4 NPs (< 50 nm) at pH - 12 resulted in the formation of additional intermediate Co(OH)2, CoOOH and alpha-FeOOH phases, with residual alpha-Fe2O3 present in the final reaction product. This research demonstrates the size and phase purity of the CoFe2O4 NPs may be controlled through the formation and dissolution of the intermediate phases at various pH values in the alkaline pH regime.


Subject(s)
Cobalt/chemistry , Crystallization/methods , Ferric Compounds/chemistry , Nanostructures/chemistry , Nanostructures/ultrastructure , Water/chemistry , Hot Temperature , Hydrodynamics , Hydrogen-Ion Concentration , Macromolecular Substances/chemistry , Materials Testing , Molecular Conformation , Particle Size , Surface Properties
10.
Environ Toxicol Pharmacol ; 25(3): 283-91, 2008 May.
Article in English | MEDLINE | ID: mdl-21783864

ABSTRACT

The U.S. Agency for Toxic Substances and Disease Registry (ATSDR) and the Polish Nofer Institute of Occupational Health collaborate on issues related to hazardous chemical exposure at or near hazardous waste sites. This paper outlines the scope of hazardous chemical exposure in the United States and in Poland and identifies priority chemicals and chemical mixtures. Special attention is paid to exposures to metals and to evaluation of the health risks associated with those exposures. Studies in the United States indicate that exposure to hazardous waste site chemicals may be associated with an increased risk of adverse developmental - specifically cardiovascular and neurodevelopmental - effects.

11.
Toxicol Mech Methods ; 18(2-3): 119-35, 2008.
Article in English | MEDLINE | ID: mdl-20020909

ABSTRACT

ABSTRACT Hazard identification and health risk assessment traditionally rely on results of experimental testing in laboratory animals. It is a lengthy and expensive process, which at the end still involves large uncertainty because the sensitivity of animals is unequal to the sensitivity of humans. The Agency for Toxic Substances and Disease Registry (ATSDR) Computational Toxicology and Method Development Laboratory develops and applies advanced computational models that augment the traditional toxicological approach with multilevel cross-extrapolation techniques. On the one hand, these techniques help to reduce the uncertainty associated with experimental testing, and on the other, they encompass yet untested chemicals, which otherwise would be left out of public health assessment. Computational models also improve understanding of the mode of action of toxic agents, and fundamental mechanisms by which they may cause injury to the people. The improved knowledge is incorporated in scientific health guidance documents of the Agency, including the Toxicological Profiles, which are used as the basis for scientifically defensible public health assessments.

12.
New Phytol ; 177(2): 506-516, 2008.
Article in English | MEDLINE | ID: mdl-18005320

ABSTRACT

Spatial genetic structure (SGS) holds the key to understanding the role of clonality in hybrid persistence, but multilocus SGS in hybrid zones has rarely been quantified. Here, the aim was to fill this gap for natural hybrids between two diploid, ecologically divergent European tree species with mixed sexual/asexual reproduction, Populus alba and P. tremula. Nuclear microsatellites were used to quantify clonality, SGS, and historical gene dispersal distances in up to 407 trees from an extensive Central European hybrid zone including three subpopulation replicates. The focus was on P. x canescens and its backcross parent P. alba, as these two genotypic classes co-occur and interact directly. Sexual recombination in both taxa was more prominent than previously thought, but P. x canescens hybrids tended to build larger clones extending over larger areas than P. alba. The 3.4 times stronger SGS in the P. x canescens genet population was best explained by a combination of interspecific gene flow, assortative mating, and increased clonality in hybrids. Clonality potentially contributes to the maintenance of hybrid zones of P. alba and P. tremula in time and space. Both clonality and SGS need to be taken into account explicitly when designing population genomics studies of locus-specific effects in hybrid zones.


Subject(s)
Ecosystem , Populus/genetics , Crosses, Genetic , Demography , Europe , Genetic Markers , Genetic Variation , Genotype , Hybridization, Genetic , Populus/classification
13.
PLoS Biol ; 5(4): e111, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17407383

ABSTRACT

Debate over repealing the ivory trade ban dominates conferences of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Resolving this controversy requires accurate estimates of elephant population trends and rates of illegal killing. Most African savannah elephant populations are well known; however, the status of forest elephants, perhaps a distinct species, in the vast Congo Basin is unclear. We assessed population status and incidence of poaching from line-transect and reconnaissance surveys conducted on foot in sites throughout the Congo Basin. Results indicate that the abundance and range of forest elephants are threatened from poaching that is most intense close to roads. The probability of elephant presence increased with distance to roads, whereas that of human signs declined. At all distances from roads, the probability of elephant occurrence was always higher inside, compared to outside, protected areas, whereas that of humans was always lower. Inside protected areas, forest elephant density was correlated with the size of remote forest core, but not with size of protected area. Forest elephants must be prioritised in elephant management planning at the continental scale.


Subject(s)
Conservation of Natural Resources , Elephants , Trees , Animals , Congo
14.
J Environ Health ; 69(1): 9-14, 24; quiz 27-8, 2006.
Article in English | MEDLINE | ID: mdl-16910103

ABSTRACT

The authors analyzed a database of acute chemical releases to describe characteristics of chemicals that may be used as weapons of terrorism. Chemicals of primary concern (Priority I) on the Chemical Terrorism Listing of the Centers for Disease Control and Prevention were cross-referenced with data for 1993-2002 from the Hazardous Substances Emergency Events Surveillance (HSEES) system. HSEES captured 58,043 single-substance releases of 2,366 chemicals during this time period. The 48 Priority I chemicals accounted for 11,567 (20 percent) of the releases, while representing only 2.0 percent of reported chemicals. Events involving Priority I chemicals resulted in twice as many victims, more injured members of the general public, more victims treated at hospitals, a higher frequency of respiratory irritation, more evacuations, more people evacuated per event, and more decontaminations than did all other HSEES events. Industry, responders, and hospitals should consider the results of this analysis in preparing for and responding to acute chemical releases.


Subject(s)
Chemical Warfare , Terrorism , Decontamination , Education, Continuing , Sentinel Surveillance
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