Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 414
Filter
1.
J AAPOS ; : 103965, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38969089

ABSTRACT

BACKGROUND: Pediatric aphakia may be treated conservatively with aphakic contacts or spectacles. Many families and surgeons opt for a secondary intraocular lens (IOL) when the child is older. In certain situations, pediatric aphakic patients must undergo implantation earlier than planned. The purpose of this study was to investigate how often and why early implantation occurs. METHODS: We retrospectively reviewed the medical records of consecutive patients who were left aphakic after cataract surgery in infancy and were seen at our institute at ≥4 years of age. Early implantation was defined as occurring at <4 years of age. RESULTS: A total of 175 patients fit inclusion criteria. We found that 22 of 90 patients (24%) with unilateral cataracts had undergone early secondary IOL implantation before 4 years of age compared to 10 of 85 patients (12%) with bilateral cataracts, a statistically significant difference in the relative risk of early implantation (OR 2.43 [95% CI 1.07-5.49]). Of our patients undergoing early implantation, 15 of 31 (44%) had Medicaid as the primary insurance provider, which is representative of the practice overall. In patients requiring early implantation, failure with contact lens accounted for 26 of 32 cases (81%), with 7 of 26 (27%) of these failures attributed to nonmedical reasons. CONCLUSIONS: Of the factors we analyzed, only the presence of unilateral aphakia was associated with increased risk of early IOL implantation in our study cohort.

2.
Nat Commun ; 9(1): 4664, 2018 11 07.
Article in English | MEDLINE | ID: mdl-30405135

ABSTRACT

PD-L1 immunohistochemistry correlates only moderately with patient survival and response to PD-(L)1 treatment. Heterogeneity of tumor PD-L1 expression might limit the predictive value of small biopsies. Here we show that tumor PD-L1 and PD-1 expression can be quantified non-invasively using PET-CT in patients with non-small-cell lung cancer. Whole body PD-(L)1 PET-CT reveals significant tumor tracer uptake heterogeneity both between patients, as well as within patients between different tumor lesions.


Subject(s)
B7-H1 Antigen/metabolism , Carcinoma, Non-Small-Cell Lung/diagnostic imaging , Lung Neoplasms/diagnostic imaging , Positron-Emission Tomography , Programmed Cell Death 1 Receptor/metabolism , Whole Body Imaging , Carcinoma, Non-Small-Cell Lung/drug therapy , Humans , Lung Neoplasms/drug therapy , Nivolumab/pharmacokinetics , Radiopharmaceuticals/pharmacokinetics , Tissue Distribution , Treatment Outcome
3.
J Phys Condens Matter ; 28(7): 076001, 2016 Feb 24.
Article in English | MEDLINE | ID: mdl-26807612

ABSTRACT

We present the results of zero-field muon-spin relaxation measurements made on the double perovskite insulators Sr2 BOsO6 (B = Fe,Y, In). Spontaneous muon-spin precession indicative of quasistatic long range magnetic ordering is observed in Sr2FeOsO6 within the AF1 antiferromagnetic phase for temperatures below [Formula: see text] K. Upon cooling below T2≈67 K the oscillations cease to be resolvable owing to the coexistence of the AF1 and AF2 phases, which leads to a broader range of internal magnetic fields. Using density functional calculations we identify a candidate muon stopping site within the unit cell, which dipole field simulations show to be consistent with the proposed magnetic structure. The possibility of incommensurate magnetic ordering is discussed for temperatures below TN = 53 K and 25 K for Sr2YOsO6 and Sr2InOsO6, respectively.

4.
Physiol Behav ; 133: 260-71, 2014 Jun 22.
Article in English | MEDLINE | ID: mdl-24866912

ABSTRACT

Domestic dogs (Canis familiaris) housed in kennelling establishments are considered at risk of suffering poor welfare. Previous research supporting this hypothesis has typically used cortisol:creatinine ratios (C/Cr) to measure acute and chronic stress in kennelled dogs. However, the value of C/Cr as a welfare indicator has been questioned. This study aimed to test the validity of a range of physiological, physical and behavioural welfare indicators and to establish baseline values reflecting good dog welfare. Measurements were taken from 29 privately-owned dogs (14 males, 15 females), ranging in age and breed, in their own home and in a boarding kennel environment, following a within-subjects, counterbalanced design. Pairwise comparisons revealed that C/Cr and vanillylmandelic acid:creatinine ratios (VMA/Cr) were higher in the kennel than home environment (P=0.003; P=0.01, respectively) and were not associated with differences in movement/exercise between environments. Dogs' surface temperature was lower in kennels (P=0.001) and was not associated with ambient temperature. No association with age, or effects of kennel establishment, kennelling experience, sex or source were found. Dogs were generally more active in kennels, but showed considerable individual variability. C/Cr and 5-HIAA:creatinine ratios (5-HIAA/Cr) were negatively correlated with lip licking in kennels. Baseline values for each parameter are presented. The emotional valence of responses was ambiguous and no definitive evidence was found to suggest that dogs were negatively stressed by kennelling. It was concluded that C/Cr and, particularly, VMA/Cr and surface temperature provide robust indicators of psychological arousal in dogs, while spontaneous behaviour might be better used to facilitate interpretation of physiological and physical data on an individual level.


Subject(s)
Behavior, Animal/physiology , Dogs/physiology , Stress, Psychological/physiopathology , Stress, Psychological/psychology , Analysis of Variance , Animals , Body Temperature/physiology , Creatine/urine , Dogs/urine , Environment , Female , Homovanillic Acid/urine , Hydrocortisone/urine , Hydroxyindoleacetic Acid/urine , Male , Malondialdehyde/urine , Motor Activity , Restraint, Physical , Thiobarbituric Acid Reactive Substances/metabolism
5.
J Anim Physiol Anim Nutr (Berl) ; 98(1): 96-9, 2014 Feb.
Article in English | MEDLINE | ID: mdl-23398054

ABSTRACT

This report describes the fecalith-induced intestinal obstruction of a free-ranging red diamond rattlesnake (Crotalus ruber) and the snake's subsequent history following surgical removal of the fecalith. The captured snake exhibited an abnormally distended abdomen and an extremely hard mass, detected via palpation, near its vent. Coeliotomy yielded a 2.5-cm, 5-g fecalith from the large intestine. Microscopic dissection of the fecalith revealed no evidence of gastrointestinal parasitic worms. Subsequently, we implanted a radio-transmitter that allowed us to track the snake's movements for 7 months (until the radio signal vanished), indicating normal behaviour, complete recovery and good health apart from the obstruction. This observation suggests that fecalith development and intestinal obstruction represent potential risks of long-term faecal retention, an unusual physiological trait well documented among rattlesnakes and other stout, heavy-bodied terrestrial viperid snakes. Dehydration and decreased gut motility associated with brumation (≈hibernation) may predispose temperate snakes to fecalith formation. Regional drought and a small mammal diet with indigestible hairs might have also promoted fecalith formation in this specimen.


Subject(s)
Animals, Wild , Constipation/veterinary , Crotalus , Fecal Impaction/veterinary , Animals , Constipation/pathology , Fecal Impaction/pathology , Fecal Impaction/surgery , Female
6.
Phys Rev Lett ; 109(6): 063203, 2012 Aug 10.
Article in English | MEDLINE | ID: mdl-23006264

ABSTRACT

The energy landscape of an atomic or molecular projectile interacting with a surface is often described in terms of a corrugation function that gives the classical turning point as a function of position vector parallel to the surface. It is shown here that the relative height variation of the corrugation function for scattering of atoms under classical conditions can be determined by a measurement of the maximum intensity in energy-resolved scattering spectra as a function of surface temperature. This is demonstrated by developing a semiclassical quantum theory of atomic scattering from corrugated surfaces and then extending the theory to the classical limit of large incident energies and high surface temperatures. Comparisons of calculations with available data for Ar atom scattering determine the corrugation amplitude for a molten In surface to be about 29% of the mean interparticle spacing in the bulk liquid.

7.
J Phys Condens Matter ; 24(35): 354001, 2012 Sep 05.
Article in English | MEDLINE | ID: mdl-22898810

ABSTRACT

Measurements of angular distributions for the scattering of well-defined incident beams of CO and N(2) molecules from a graphite surface are presented. The measurements were carried out over a range of graphite surface temperatures from 150 to 400 K and a range of incident translational energies from 275 to over 600 meV. The behavior of the widths, positions and relative intensities of the angular distributions for both CO and N(2) were found to be quite similar. The experimental measurements are discussed in comparison with calculations using a classical mechanical model that describes single collisions with a surface. Based on the behavior of the angular distributions as functions of temperature and incident translational energy, and the agreement between measured data and calculations of the single-collision model, it is concluded that the scattering process is predominantly a single collision with a collective surface for which the effective mass is significantly larger than that of a single carbon atom. This conclusion is consistent with that of earlier experiments for molecular beams of O(2) molecules and Xe atoms scattering from graphite. Further calculations are carried out with the theoretical molecular scattering model in order to predict translational and rotational energy transfers to and from the molecule during scattering events under similar initial conditions.

8.
J Phys Condens Matter ; 24(10): 104010, 2012 Mar 14.
Article in English | MEDLINE | ID: mdl-22353319

ABSTRACT

Recently an extensive series of measurements has been presented for the angular distributions of oxygen molecules scattered from a graphite surface. Incident translational energies ranged from 291 to 614 meV with surface temperatures from 150 to 500 K. The measurements were taken with a fixed angle of 90° between the source beam and the detector and the angular distributions consisted of a single broad peak with the most probable intensity located at an angle slightly larger than the 45° specular position. Analysis with the hard cubes model for atom-surface scattering indicated that the scattering is primarily a single collision event with a surface having a collective effective mass much larger than a single carbon atom. Limited analysis with a classical diatomic molecular scattering theory was also presented. In this paper a more complete analysis using the classical diatomic molecular scattering theory is presented. The energy and temperature dependence of the observed angular distributions are well described as single collision events with a surface having an effective mass of 1.8 carbon graphite rings. In agreement with the earlier analysis and with other experiments, this suggests a large cooperative response of the carbon atoms in the outermost graphene layer.

9.
J Long Term Eff Med Implants ; 21(3): 185-92, 2011.
Article in English | MEDLINE | ID: mdl-22150350

ABSTRACT

Treatment of distal metaphyseal tibia fractures is often challenging. Newer tibial intramedullary (IM) nails are designed with a wider variety of distal locking options to offer greater stability in treating these fractures. In this study we attempted to determine the most biomechanically stable number and configuration of distal locking screws when treating distal metaphyseal tibia fractures with IM nails. A transverse osteotomy was created 4 cm from the tibial plafond in identical composite saw bones models (Type 43A fracture) as well as in human cadaveric bones. Each specimen was nailed using a tibial nail (Stryker T2). Distal locking was performed in one of the three configurations: (a) Group I: two screws in the medial lateral (ML) direction; (b) Group II: one ML screw and one screw in the anterior posterior (AP) direction; (c) Group 111: two ML screws and one AP screw. The specimens were then mounted onto a uniaxial material testing machine (Instron) and tested in compression. Our results showed that there was no statistical difference in the load-carrying capacity of Group 1 and Group II. This suggests that the treating surgeon can choose either of these two configurations depending on the wound or other considerations without sacrificing the compressive load-carrying capacity of the IM nail fixation. The load-carrying capacity of the Group III samples with these locking screws was higher than those of Group I & II, although this difference was not statistically significant. This work is being continued to compare the load-carrying capacity of the bone samples with the cortical thickness of bone. We also plan to examine the relationship between the load-carrying capacity of these surgical constructs with the bone mineral density of the metaphysis of these tibial specimens.


Subject(s)
Bone Nails , Bone Screws , Compressive Strength , Fracture Fixation, Intramedullary/instrumentation , Tibial Fractures/surgery , Aged , Aged, 80 and over , Cadaver , Equipment Design , Equipment Failure Analysis , Female , Humans , Male , Middle Aged
10.
J Phys Condens Matter ; 23(48): 484003, 2011 Dec 07.
Article in English | MEDLINE | ID: mdl-22085838

ABSTRACT

It is suggested that a measurement of the temperature dependence of the most probable intensity of energy-resolved atom-surface scattering spectra can reveal the strength of the surface corrugation. To support this conjecture, a classical mechanical theory of atom scattering from a corrugated surface, valid in the weak corrugation limit, is developed. The general result for the scattering probability is expressed in terms of spatial integrals over the impact parameter within a surface unit cell. For the case of a one-dimensional corrugation, approximate expressions for the scattering probability are obtained in terms of analytic closed form expressions. As an indicator of its relation to experimental measurements, calculations using a one-dimensional corrugation model are compared with data for Ar scattering from a molten Ga surface and an approximate value of the corrugation height parameter is extracted.

11.
Br J Cancer ; 105(1): 44-52, 2011 Jun 28.
Article in English | MEDLINE | ID: mdl-21629245

ABSTRACT

BACKGROUND: The objectives of this phase I study were to determine the safety, pharmacokinetics (PK), pharmacodynamics and efficacy of brivanib combined with full-dose cetuximab in patients with advanced gastrointestinal malignancies. METHODS: Patients with advanced gastrointestinal malignancies who had failed prior therapies received brivanib (320, 600 or 800 mg daily) plus cetuximab (400 mg m(-2) loading dose then 250 mg m(-2) weekly). Assessments included adverse events, PK, tumour response, 2[18F]fluoro-2-deoxyglucose positron-emitting tomography and K-Ras mutation analyses. RESULTS: Toxicities observed were manageable; the most common treatment-related toxicities (>10% of patients) were fatigue, diarrhoea, anorexia, increase in aspartate aminotransferase and alanine aminotransferase, acneiform dermatitis, headache, mucosal inflammation, nausea, dry skin, vomiting, hypertension, pruritus, proteinuria and weight loss. Of 62 patients, 6 (9.7%) had objective radiographic partial responses, with an overall response rate of 10%. Median duration of response was 9.2 months; median progression-free survival was 3.9 months. CONCLUSIONS: The acceptable toxicity profile and efficacy of brivanib observed in this study were promising. These findings are being further evaluated in a phase III study of brivanib plus cetuximab vs cetuximab alone in patients previously treated with combination chemotherapy for K-Ras wild-type advanced metastatic colorectal cancer.


Subject(s)
Alanine/analogs & derivatives , Antibodies, Monoclonal/pharmacokinetics , Antibodies, Monoclonal/therapeutic use , Gastrointestinal Neoplasms/drug therapy , Salvage Therapy , Triazines/pharmacokinetics , Triazines/therapeutic use , Adult , Aged , Alanine/pharmacokinetics , Alanine/therapeutic use , Antibodies, Monoclonal, Humanized , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/therapeutic use , Cetuximab , Drug Therapy, Combination , Female , Gastrointestinal Neoplasms/pathology , Humans , Male , Middle Aged , Neoplasm Recurrence, Local/drug therapy , Neoplasm Recurrence, Local/pathology , Survival Rate , Tissue Distribution , Treatment Outcome , Vascular Endothelial Growth Factor Receptor-2/antagonists & inhibitors
12.
J Phys Chem A ; 115(25): 6838-42, 2011 Jun 30.
Article in English | MEDLINE | ID: mdl-21410274

ABSTRACT

Recently a series of experimental measurements for the scattering of Xe atoms from graphite has been reported for both energy-resolved spectra and angular distributions. This system is of fundamental interest because the projectile Xe atoms are considerably more massive than the carbon atoms making up the graphite surface. These measurements were initially analyzed using the hard cubes model and molecular dynamics simulations, and both treatments indicated that the scattering process was a single collision in which the incoming Xe atom interacted strongly with a large number of carbon atoms in the outermost graphite layer. In this work we analyze the data using a single scattering theory that has been shown to explain a number of other experiments on molecular beam scattering from surfaces. These calculations confirm that the scattering process is a single collision with an effective surface mass that is substantially larger than that of the basic graphite ring.

13.
J Phys Chem A ; 115(25): 7089-95, 2011 Jun 30.
Article in English | MEDLINE | ID: mdl-21446680

ABSTRACT

The scattering of the oxygen molecule from a graphite surface has been studied using a molecular beam scattering technique. The angular intensity distributions of scattered oxygen molecules were measured at incident energies from 291 to 614 meV with surface temperatures from 150 to 500 K. Every observed distribution has a single peak at a larger final angle than the specular angle of 45° which indicates that the normal component of the translation energy of the oxygen molecule is lost by the collision with the graphite surface. The amount of the energy loss by the collision has been roughly estimated as about 30-41% based on the assumption of the tangential momentum conservation during the collision. The distributions have also been analyzed with two theoretical models, the hard cubes model and the smooth surface model. These results indicate that the scattering is dominated by a single collision event of the particle with a flat surface having a large effective mass. The derived effective mass of the graphite surface for the incoming oxygen is 9-12 times heavier than that of a single carbon atom, suggesting a large cooperative motion of the carbon atoms in the topmost graphene layer.

14.
PLoS One ; 5(8): e12407, 2010 Aug 25.
Article in English | MEDLINE | ID: mdl-20811636

ABSTRACT

Telomere integrity (including telomere length and capping) is critical in overall genomic stability. Telomere repeat binding factors and their associated proteins play vital roles in telomere length regulation and end protection. In this study, we explore the protein network surrounding telomere repeat binding factors, TRF1, TRF2, and POT1 using dual-tag affinity purification in combination with multidimensional protein identification technology liquid chromatography--tandem mass spectrometry (MudPIT LC-MS/MS). After control subtraction and data filtering, we found that TRF2 and POT1 co-purified all six members of the telomere protein complex, while TRF1 identified five of six components at frequencies that lend evidence towards the currently accepted telomere architecture. Many of the known TRF1 or TRF2 interacting proteins were also identified. Moreover, putative associating partners identified for each of the three core components fell into functional categories such as DNA damage repair, ubiquitination, chromosome cohesion, chromatin modification/remodeling, DNA replication, cell cycle and transcription regulation, nucleotide metabolism, RNA processing, and nuclear transport. These putative protein-protein associations may participate in different biological processes at telomeres or, intriguingly, outside telomeres.


Subject(s)
Telomere-Binding Proteins/metabolism , Telomeric Repeat Binding Protein 1/metabolism , Telomeric Repeat Binding Protein 2/metabolism , Cell Line , Chromatography, Liquid , Humans , Mass Spectrometry , Protein Binding , Shelterin Complex
15.
J Phys Condens Matter ; 22(30): 304010, 2010 Aug 04.
Article in English | MEDLINE | ID: mdl-21399342

ABSTRACT

Supersonic He and Ar atomic beam scattering from C(60) and graphene monolayers adsorbed on a Pt(111) surface are demonstrated in order to obtain detailed insight into a gas-molecule collision that has not been studied in detail so far. The effective masses and phonon spectral densities of the monolayers seen by different projectiles are discussed based on classical models such as the hard cube model and the recently developed smooth surface model. Large effective masses are deduced for both the monolayers, suggesting collective effects of surface atoms in the single collision event. The effective Debye temperature of graphene was found to be similar to that reported in highly oriented pyrolytic graphite (HOPG), indicating that the graphene is decoupled well from the Pt substrate. A much smaller Debye-Waller factor was found for the C(60) layer, probably reflecting the strong C(60)-Pt(111) interaction.

16.
Eur J Vasc Endovasc Surg ; 38(2): 188-91, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19395290

ABSTRACT

OBJECTIVES: Botulinum toxin injection effectively treats axillary hyperhidrosis. Durability estimates of 3-14 months, based on self re-referral may overestimate duration. Our objective was to determine treatment durability by active follow-up of patients. DESIGN: Audit of current practice. MATERIALS AND METHODS: Patients presenting with severe primary axillary hyperhidrosis were actively followed up for 24 months after intradermal injections of Botulinum Toxin A (Dysport 120 units/axilla). A 10-point Likert Scale (1=worst imaginable symptoms, 10=absolute resolution) and the Hyperhidrosis Disease Severity Score (HDSS) were used at 1 day and 3, 6, 12 and 24 months. We offered re-treatment when symptoms returned to the pre-intervention state. RESULTS: We treated 45 patients with a mean age of 29 (15-49) years of whom 36 (78%) were women. The median pre-treatment Likert score (i.q.r.) of 3 (2-3) improved to 10 (10-10) on day 1. Scores at 3 (n=44), 6 (n=43) and 12 (n=39) months were 10 (10-10), 8 (7.5-10), and 7 (5-8) respectively. The median 24-month score was 3 (3-6) for 35 patients, including 11 patients with scores >/=6 who have not required re-treatment. HDSS scores followed a similar pattern. CONCLUSIONS: Axillary botulinum toxin treatment is durable. Patients experience gradual return of symptoms between 6 and 24 months. A minority do not require re-treatment at this time.


Subject(s)
Botulinum Toxins, Type A/administration & dosage , Hyperhidrosis/drug therapy , Neuromuscular Agents/administration & dosage , Adolescent , Adult , Drug Administration Schedule , Female , Follow-Up Studies , Humans , Injections, Intradermal , Kaplan-Meier Estimate , Male , Middle Aged , Severity of Illness Index , Time Factors , Treatment Outcome , Young Adult
17.
Phys Rev Lett ; 100(1): 017206, 2008 Jan 11.
Article in English | MEDLINE | ID: mdl-18232815

ABSTRACT

Zero-field muon-spin relaxation measurements of the frustrated triangular quantum magnet AgNiO2 are consistent with a model of charge disproportionation that has been advanced to explain the structural and magnetic properties of this compound. Below an ordering temperature of TN=19.9(2) K we observe six distinct muon precession frequencies, due to the magnetic order, which can be accounted for with a model describing the probable muon sites. The precession frequencies show an unusual temperature evolution which is suggestive of the separate evolution of two opposing magnetic sublattices.

18.
J Phys Condens Matter ; 20(46): 465203, 2008 Nov 19.
Article in English | MEDLINE | ID: mdl-21693843

ABSTRACT

We report muon spin relaxation (µSR) measurements on two Ti(3+) containing perovskites, LaTiO(3) and YTiO(3), which display long-range magnetic order at low temperature. For both materials, oscillations in the time dependence of the muon polarization are observed which are consistent with three-dimensional magnetic order. From our data we identify two magnetically inequivalent muon stopping sites. The µSR results are compared with the magnetic structures of these compounds previously derived from neutron diffraction and µSR studies on structurally similar compounds.

19.
J Chem Phys ; 127(16): 164714, 2007 Oct 28.
Article in English | MEDLINE | ID: mdl-17979378

ABSTRACT

Newly available experimental data for the scattering of argon, neon, and xenon atoms from molten gallium, indium, and bismuth surfaces are compared to calculations with classical scattering theory. The results of the theory are in reasonable agreement with observed energy-resolved spectra taken at fixed angles, with in-plane angular distributions, and with the first available out-of-plane angular distribution spectra for these systems. For all three of the rare gases, scattering from liquid Ga required the use of an effective surface mass equal to 1.65 times the mass of a single Ga atom. The need for a larger effective mass has been noted previously for Ar/Ga scattering and is indicative of collective effects in the liquid Ga. Comparisons with data taken at low incident energies enable estimates of the physisorption well depth in the interaction potentials for many of the gas-metal combinations.

20.
Phys Rev Lett ; 98(19): 197203, 2007 May 11.
Article in English | MEDLINE | ID: mdl-17677657

ABSTRACT

The ferroelectromagnet YMnO3 consists of weakly coupled triangular layers of S=2 spins. Below T(N) approximately equal to 70 K muon-spin relaxation data show two oscillatory relaxing signals due to magnetic order, with no purely relaxing signals resolvable (which would require different coexisting spin distributions). The transition temperature T(N) increases with applied hydrostatic pressure, even though the ordered moment decreases. These results suggest that pressure increases both the exchange coupling between the layers and the frustration within the layers.

SELECTION OF CITATIONS
SEARCH DETAIL
...