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1.
Appl Radiat Isot ; 156: 108951, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31790976

ABSTRACT

With the advancement of high-precision radiotherapy and the increasing use of higher intensity beams, the risk to the patient increases should the radiotherapy machine malfunction. Hence more accurate treatment verification is required. In this paper we provide a solution for real-time monitoring of X-ray beams from radiotherapy linear accelerators using monolithic active pixel sensors. We show that leaf errors can be detected with high precision in static fields and IMRT step and shoot, and accurate leaf tracking is possible in Volumetric Modulated Arc Therapy. The prototype MAPS detector meets the criteria of 1% attenuation acceptable for clinical use.


Subject(s)
Radiotherapy, Intensity-Modulated/methods , Humans , Radiotherapy Planning, Computer-Assisted/methods , Silicon/chemistry
2.
J Virol ; 93(6)2019 03 15.
Article in English | MEDLINE | ID: mdl-30626676

ABSTRACT

The Sf9 and Sf21 cell lines derived from ovarian tissues of the wide-host-range phytophagous lepidopteran Spodoptera frugiperda are widely used for research and commercial-scale production of recombinant proteins. These cell lines are chronically infected with a rhabdovirus (Sf-RV) that does not cause any overt cytopathic effects. We demonstrate that wild populations of S. frugiperda in the eastern United States and Caribbean are infected with genetically diverse strains of Sf-RV and that this virus is also capable of infecting cells of Spodoptera exigua, Heliothis subflexa, and Bombyx mori Feeding studies demonstrated the ability of S. frugiperda larvae to deposit Sf-RV onto human-consumed vegetables during feeding. Although no evidence for replication in two species of plant cells was detected, subcellular localization studies demonstrated that the Sf-RV nucleocapsid was targeted to plasmodesmata, while two forms of the accessory protein were differentiated on the basis of their ability to localize to nuclei. Collectively, the results from this study suggest that environmental exposure of humans to Sf-RV is likely to be commonplace and frequent, but its inability to replicate in plant or human cells suggests that there is no substantial risk to human health.IMPORTANCE Insect-derived cell lines are widely used commercially for the production of vaccines and protein-based pharmaceuticals. After decades of safe and beneficial use, it was a surprise to the biotechnology industry to discover an endemic rhabdovirus in Sf9 cells. This discovery was made possible only by the substantial advancements in DNA sequencing technologies. Given the public health concerns associated with many rhabdovirus species, several initiatives were undertaken to establish that Spodoptera frugiperda rhabdovirus (Sf-RV) does not pose a threat to humans. Such actions include the generation of cell lines that have been cleared of Sf-RV. Given that Sf9 is derived from a moth whose larvae feed on human-edible foods, we explored the prevalence of Sf-RV in its wild and lab-grown populations, as well as its ability to be deposited on food items during feeding. Collectively, our data suggest that there is no overt risk from exposure to Sf-RV.


Subject(s)
Host Specificity/physiology , Rhabdoviridae/physiology , Spodoptera/virology , Animals , Cell Line , Humans , Insecta/virology , Larva/metabolism , Larva/virology , Plants/virology , Recombinant Proteins/metabolism , Rhabdoviridae/metabolism , Sf9 Cells , Spodoptera/metabolism , Viral Proteins/metabolism
3.
Eur Psychiatry ; 50: 34-39, 2018 04.
Article in English | MEDLINE | ID: mdl-29398565

ABSTRACT

Postoperative cognitive impairment is among the most common medical complications associated with surgical interventions - particularly in elderly patients. In our aging society, it is an urgent medical need to determine preoperative individual risk prediction to allow more accurate cost-benefit decisions prior to elective surgeries. So far, risk prediction is mainly based on clinical parameters. However, these parameters only give a rough estimate of the individual risk. At present, there are no molecular or neuroimaging biomarkers available to improve risk prediction and little is known about the etiology and pathophysiology of this clinical condition. In this short review, we summarize the current state of knowledge and briefly present the recently started BioCog project (Biomarker Development for Postoperative Cognitive Impairment in the Elderly), which is funded by the European Union. It is the goal of this research and development (R&D) project, which involves academic and industry partners throughout Europe, to deliver a multivariate algorithm based on clinical assessments as well as molecular and neuroimaging biomarkers to overcome the currently unsatisfying situation.


Subject(s)
Cognitive Dysfunction/etiology , Neuroimaging , Postoperative Complications/diagnosis , Biomarkers , Cognitive Dysfunction/diagnosis , Europe , European Union , Humans , Risk Assessment , Risk Factors
4.
Psychol Med ; 48(5): 790-800, 2018 04.
Article in English | MEDLINE | ID: mdl-28832300

ABSTRACT

BACKGROUND: Previous studies have highlighted the role of the brain reward and cognitive control systems in the etiology of anorexia nervosa (AN). In an attempt to disentangle the relative contribution of these systems to the disorder, we used functional magnetic resonance imaging (fMRI) to investigate hemodynamic responses to reward-related stimuli presented both subliminally and supraliminally in acutely underweight AN patients and age-matched healthy controls (HC). METHODS: fMRI data were collected from a total of 35 AN patients and 35 HC, while they passively viewed subliminally and supraliminally presented streams of food, positive social, and neutral stimuli. Activation patterns of the group × stimulation condition × stimulus type interaction were interrogated to investigate potential group differences in processing different stimulus types under the two stimulation conditions. Moreover, changes in functional connectivity were investigated using generalized psychophysiological interaction analysis. RESULTS: AN patients showed a generally increased response to supraliminally presented stimuli in the inferior frontal junction (IFJ), but no alterations within the reward system. Increased activation during supraliminal stimulation with food stimuli was observed in the AN group in visual regions including superior occipital gyrus and the fusiform gyrus/parahippocampal gyrus. No group difference was found with respect to the subliminal stimulation condition and functional connectivity. CONCLUSION: Increased IFJ activation in AN during supraliminal stimulation may indicate hyperactive cognitive control, which resonates with clinical presentation of excessive self-control in AN patients. Increased activation to food stimuli in visual regions may be interpreted in light of an attentional food bias in AN.


Subject(s)
Anorexia Nervosa/physiopathology , Cerebral Cortex/physiopathology , Food , Functional Neuroimaging/methods , Pattern Recognition, Visual/physiology , Reward , Subliminal Stimulation , Adolescent , Adult , Anorexia Nervosa/diagnostic imaging , Cerebral Cortex/diagnostic imaging , Female , Humans , Magnetic Resonance Imaging , Young Adult
5.
Sci Rep ; 7(1): 17146, 2017 12 07.
Article in English | MEDLINE | ID: mdl-29215067

ABSTRACT

The symptoms of malaria are brought about by blood-stage parasites, which are established when merozoites invade human erythrocytes. Our understanding of the molecular events that underpin erythrocyte invasion remains hampered by the short-period of time that merozoites are invasive. To address this challenge, a Plasmodium falciparum gamma-irradiated long-lived merozoite (LLM) line was developed and investigated. Purified LLMs invaded erythrocytes by an increase of 10-300 fold compared to wild-type (WT) merozoites. Using an integrated omics approach, we investigated the basis for the phenotypic difference. Only a few single nucleotide polymorphisms within the P. falciparum genome were identified and only marginal differences were observed in the merozoite transcriptomes. By contrast, using label-free quantitative mass-spectrometry, a significant change in protein abundance was noted, of which 200 were proteins of unknown function. We determined the relative molar abundance of over 1100 proteins in LLMs and further characterized the major merozoite surface protein complex. A unique processed MSP1 intermediate was identified in LLM but not observed in WT suggesting that delayed processing may be important for the observed phenotype. This integrated approach has demonstrated the significant role of the merozoite proteome during erythrocyte invasion, while identifying numerous unknown proteins likely to be involved in invasion.


Subject(s)
Erythrocytes/metabolism , Malaria, Falciparum/metabolism , Merozoites/metabolism , Plasmodium falciparum/metabolism , Proteome , Protozoan Proteins/metabolism , Transcriptome , Animals , Erythrocytes/parasitology , Humans , Malaria, Falciparum/genetics , Malaria, Falciparum/parasitology , Merozoites/genetics , Plasmodium falciparum/genetics , Plasmodium falciparum/isolation & purification , Protozoan Proteins/genetics
6.
Bone Joint J ; 99-B(1 Supple A): 8-13, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28042112

ABSTRACT

AIMS: The purpose of this article was to review the current literature pertaining to the use of mobile compression devices (MCDs) for venous thromboembolism (VTE) following total joint arthroplasty (TJA), and to discuss the results of data from our institution. PATIENTS AND METHODS: Previous studies have illustrated higher rates of post-operative wound complications, re-operation and re-admission with the use of more aggressive anticoagulation regimens, such as warfarin and factor Xa inhibitors. This highlights the importance of the safety, as well as efficacy, of the chemoprophylactic regimen. RESULTS: Studies have shown a symptomatic VTE rate of 0.92% with use of MCDs for prophylaxis, which is comparable with rates seen with more aggressive anticoagulation protocols. A prior prospective study found that use of a pre-operative risk stratification protocol based on personal history of deep vein thrombosis, family history of VTE, active cancer, or a hypercoaguable state allowed for the avoidance of aggressive prophylactic anticoagulation in over 70% of patients while maintaining a low incidence of symptomatic VTE. CONCLUSION: Further investigation is needed into the role of aspirin in VTE prophylaxis as well as the efficacy of MCDs as stand-alone prophylactic treatment. Cite this article: Bone Joint J 2017;99-B(1 Supple A):8-13.


Subject(s)
Arthroplasty, Replacement/adverse effects , Intermittent Pneumatic Compression Devices , Venous Thromboembolism/prevention & control , Venous Thrombosis/prevention & control , Adult , Aged , Ambulatory Care/methods , Anticoagulants/adverse effects , Anticoagulants/therapeutic use , Aspirin/therapeutic use , Combined Modality Therapy , Humans , Middle Aged , Postoperative Care/methods , Postoperative Hemorrhage/etiology , Risk Assessment/methods , Venous Thromboembolism/etiology , Venous Thrombosis/etiology , Warfarin/therapeutic use , Young Adult
7.
Bone Joint J ; 99-B(1 Supple A): 31-36, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28042116

ABSTRACT

AIMS: The purpose of our study is to summarise the current scientific findings regarding the impact of obesity on total hip arthroplasty (THA); specifically the influence of obesity on the timing of THA, incidence of complications, and effect on clinical and functional outcomes. MATERIALS AND METHODS: We performed a systematic review that was compliant with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify prospective studies from the PubMed/Medline, Embase, and Cochrane Library databases that evaluated primary THA in obese (body mass index (BMI) ≥ 30 kg/m2) patients. RESULTS: There were 17 articles included in the review, which encompassed 13 722 THA patients. Analysis of the included studies showed that, when compared with non-obese patients, obesity was associated with younger age at time of primary THA, and an increased incidence of complications (up to four-fold). Results were mixed on the influence of obesity on the outcomes of primary THA, with three studies showing a detrimental effect on outcomes of a BMI ≥ 30 kg/m2, while eight studies showed no effect. CONCLUSION: Obesity is associated with significantly younger age at time of primary THA and obese patients are likely to experience a higher rate of peri-operative complications. More investigation is needed into the effect of obesity on clinical outcomes, as the current literature is mixed. Cite this article: Bone Joint J 2017;99-B(1 Supple A):31-6.


Subject(s)
Arthroplasty, Replacement, Hip/adverse effects , Obesity/complications , Age Factors , Hip Dislocation/etiology , Humans , Postoperative Complications , Risk Factors , Treatment Outcome
8.
Neurochem Int ; 106: 3-13, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28065797

ABSTRACT

In the developing ventral telencephalon, cells of the lateral ganglionic eminence (LGE) give rise to all medium spiny neurons (MSNs). This development occurs in response to a highly orchestrated series of morphogenetic stimuli that pattern the resultant neurons as they develop. Striatal MSNs are characterised by expression of dopamine receptors, dopamine-and cyclic AMP-regulated phosphoprotein (DARPP32) and the neurotransmitter GABA. In this study, we demonstrate that fine tuning Wnt and hedgehog (SHH) signaling early in human embryonic stem cell differentiation can induce a subpallial progenitor molecular profile. Stimulation of TGFß signaling pathway by activin-A further supports patterning of progenitors to striatal precursors which adopt an LGE-specific gene signature. Moreover, we report that these MSNs also express markers associated with mature neuron function (cannabinoid, adenosine and dopamine receptors). To facilitate live-cell identification we generated a human embryonic stem cell line using CRISPR-mediated gene editing at the DARPP32 locus (DARPP32WT/eGFP-AMP-LacZ). The addition of dopamine to MSNs either increased, decreased or had no effect on intracellular calcium, indicating the presence of multiple dopamine receptor subtypes. In summary, we demonstrate greater control over early fate decisions using activin-A, Wnt and SHH to direct differentiation into MSNs. We also generate a DARPP32 reporter line that enables deeper pharmacological profiling and interrogation of complex receptor interactions in human MSNs.


Subject(s)
Cell Differentiation/physiology , Clustered Regularly Interspaced Short Palindromic Repeats/physiology , Dopamine and cAMP-Regulated Phosphoprotein 32/physiology , Genes, Reporter/physiology , Human Embryonic Stem Cells/physiology , Neurons/physiology , Cell Line , Hedgehog Proteins/physiology , Humans , Wnt Signaling Pathway/physiology
9.
Sci Technol Adv Mater ; 18(1): 828-838, 2017.
Article in English | MEDLINE | ID: mdl-29379579

ABSTRACT

Recent progress in high-performance computing and data informatics has opened up numerous opportunities to aid the design of advanced materials. Herein, we demonstrate a computational workflow that includes rapid population of high-fidelity materials datasets via petascale computing and subsequent analyses with modern data science techniques. We use a first-principles approach based on density functional theory to derive the segregation energies of 34 microalloying elements at the coherent and semi-coherent interfaces between the aluminium matrix and the θ'-Al2Cu precipitate, which requires several hundred supercell calculations. We also perform extensive correlation analyses to identify materials descriptors that affect the segregation behaviour of solutes at the interfaces. Finally, we show an example of leveraging machine learning techniques to predict segregation energies without performing computationally expensive physics-based simulations. The approach demonstrated in the present work can be applied to any high-temperature alloy system for which key materials data can be obtained using high-performance computing.

10.
CBE Life Sci Educ ; 15(3)2016.
Article in English | MEDLINE | ID: mdl-27562959

ABSTRACT

Equal representation within higher education science, technology, engineering, and mathematics (STEM) fields and the STEM workforce in the United States across demographically diverse populations is a long-standing challenge. This study uses two-to-one nearest-neighbor matched-comparison group design to examine academic achievement, pursuit of graduate science degree, and classification of graduate institution attended by students participating in the Hopps Scholars Program (Hopps) at Morehouse College. Hopps is a highly structured enrichment program aimed at increasing participation of black males in STEM fields. Morehouse institutional records, Hopps Program records, and National Student Clearinghouse data were used to examine differences between Hopps and non-Hopps STEM graduates of Morehouse. Two-way sample t tests and chi-square tests revealed significant differences in academic achievement, likelihood of STEM degree pursuit, and the classification of graduate institutions attended by Hopps versus non-Hopps students. Hopps Scholars were significantly more likely than non-Hopps STEM graduates both to pursue STEM doctoral degrees and to attend doctoral-granting institutions with higher research activity. The Hopps Program's approach to training black male students for scientific careers is a model of success for other programs committed to increasing the number of black males pursuing advanced degrees in STEM.


Subject(s)
Career Choice , Minority Groups/education , Research , Science/education , Universities , Demography , Education, Graduate , Educational Measurement , Engineering/education , Humans , Male , Mathematics/education , Propensity Score , Technology/education
11.
Drug Alcohol Depend ; 159: 263-6, 2016 Feb 01.
Article in English | MEDLINE | ID: mdl-26710978

ABSTRACT

BACKGROUND: Pharmacotherapeutic agents that could facilitate extinction of cocaine cues would be useful in the treatment of cocaine addiction. We tested whether SR 21502, a selective dopamine (DA) D3 receptor antagonist, can facilitate extinction of cocaine conditioned place preference (CPP) in rats. METHODS: In experiment 1, cocaine (10mg/kg) CPP was first established and then extinguished. During the extinction phase the rats were injected with SR 21502 and placed in the previously cocaine-paired compartment for four sessions and vehicle in the other compartment on four alternating sessions. The rats were then tested again for cocaine CPP. In experiment 2, different groups of rats were trained to associate SR 21502 with one compartment and saline with the other. RESULTS: In experiment 1, the animals spent significantly more time in the cocaine-paired compartment after cocaine conditioning than they did before conditioning. Subsequently, the animals treated with SR 21502 during the extinction phase spent significantly less time in the cocaine-paired compartment than the vehicle group. In experiment 2, animals conditioned with SR 21502 preferred neither side of the CPP apparatus, indicating that SR 21502 produced no effects of its own. CONCLUSIONS: These findings suggest that treatment with SR 21502, a DA D3 receptor antagonist, in the presence of cocaine cues can facilitate extinction of cocaine CPP and further suggest that this compound might be an effective cocaine addiction treatment.


Subject(s)
Cocaine/pharmacology , Conditioning, Psychological/drug effects , Extinction, Psychological/drug effects , Imidazoles/pharmacology , Pyridines/pharmacology , Receptors, Dopamine D3/antagonists & inhibitors , Animals , Cues , Male , Rats
12.
Article in English | MEDLINE | ID: mdl-25957031

ABSTRACT

Pluripotent stem cells offer an unparalleled opportunity to investigate cardiac physiology, pharmacology, toxicology and pathophysiology. In this paper we describe the use of both mouse (Nkx2-5(eGFP/w)) and human (NKX2-5(eGFP/w)) pluripotent stem cell reporter lines, differentiated toward cardiac lineage, for live single cell high acquisition rate calcium imaging. We also assess the potential of NKX2-5(eGFP/w) cardiac lineage cells for use toxicological screening as well as establish their sensitivity to a shift between low and high oxygen environments. Differentiated mouse Nkx2-5(eGFP/w) cells demonstrated a wide range of spontaneous oscillation rates that could be reduced by ryanodine (10µM), thapsigargin (1µM) and ZD7288 (10µM). In contrast human NKX2-5(eGFP/w) cell activity was only reduced by thapsigargin (1µM). Human cell survival was sensitive to the addition of trastuzumab and doxorubicin, while the switch from a low to a high oxygen environment affected oscillation frequency. We suggest that the human NKX2-5(eGFP/w) cells are less suitable for studies of compounds affecting cardiac pacemaker activity than mouse Nkx2-5(eGFP/w) cells, but are very suitable for cardiac toxicity studies.


Subject(s)
Myocytes, Cardiac/physiology , Pluripotent Stem Cells/physiology , Animals , Biological Clocks/physiology , Cell Differentiation/physiology , Cell Survival/physiology , Humans , Mice , Myocytes, Cardiac/metabolism , Oxygen/metabolism , Pluripotent Stem Cells/metabolism
13.
Vet Pathol ; 52(2): 360-3, 2015 Mar.
Article in English | MEDLINE | ID: mdl-24823807

ABSTRACT

The placenta from an embryo transfer-recipient mare and live foal was examined. The placenta was effaced by multifocal masses, which ranged from less than 1 cm to 14 cm in diameter. The foal represented at 52 days for lethargy, ataxia, and urine dribbling; due to a poor prognosis, the foal was euthanized. At necropsy, the liver was effaced by multifocal, pale, irregular nodules. The lumbar vertebrae and other skeletal sites had multifocal lytic lesions. The placenta had 4 populations of neoplastic cells, including a spindle cell population, tall columnar and transitional epithelial cell populations, and an undifferentiated polygonal cell population. The foal's liver had similar populations and patterns of cells as those in the placenta. The lesion in the placenta and the masses in the foal were diagnosed as a mixed germ cell tumor and metastatic mixed germ cell tumor, respectively.


Subject(s)
Biomarkers, Tumor/metabolism , Horse Diseases/pathology , Liver Neoplasms/veterinary , Neoplasms, Germ Cell and Embryonal/veterinary , Animals , Animals, Newborn , Female , Horses , Liver/pathology , Liver Neoplasms/secondary , Neoplasm Metastasis , Neoplasms, Germ Cell and Embryonal/pathology , Placenta/pathology , Pregnancy
14.
J Wound Care ; 23(11): 532, 534, 536 passim, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25375401

ABSTRACT

OBJECTIVE: This article assesses the use of BeneHold Thin Absorbent Skin Adhesive (TASA) wound dressings in a large UK primary care organisation. These wound dressings are thin (0.12 mm), breathable, transparent, and are able to absorb and retain wound exudate. This non-comparative evaluation was undertaken to explore the clinical advantages this differentiated combination of physical properties offered. METHOD: The dressings are CE-marked medical devices, and were used on patients with acute and chronic wounds that were assessed and classified as light to moderately exuding. Clinical performance was evaluated with respect to the dressing's ease of use (application and removal, conformability, mould-ability, rolling and edge-lift), debridement, protection of the peri-wound, wear time, fluid handling, wound bed residue, visibility of the wound, and clinical acceptability. The evaluating clinicians used an agreed audit tool to collect data from case reports to document the progression of wounds of various aetiologies, including chronic and acute, for a maximum period of four weeks. Qualitative feedback on dressing performance was also collected at the evaluation's end, both from the clinicians' and patients' perspectives Results: Some 15 patients were assessed. The wear time was up to seven days in many cases, and on average was 3.9 days longer than their previous dressings. Clinicians perceived that wounds progressed toward healing in all but two cases, where the wounds remained unchanged. Out of five cases where wounds presented with necrosis, all underwent significant autolytic debridement underneath the new dressings. Transparency was a noted benefit from both the clinicians' and patients' perspectives because it enabled continuous monitoring of the full wound bed and peri-wound skin without the need to disrupt the dressing. CONCLUSION: The dressing was well-received by both clinicians and patients in all fifteen cases. The thin absorbent skin adhesive dressing was found to be a promising new technology that could offer significant advantages to improve the quality, cost, and convenience of wound care. Further work is underway to validate these findings in larger and more homogeneous patient groups.


Subject(s)
Bandages, Hydrocolloid , Wound Healing , Wounds and Injuries/pathology , Wounds and Injuries/therapy , Adolescent , Adult , Aged , Aged, 80 and over , Exudates and Transudates , Female , Humans , Male , Middle Aged , Necrosis/prevention & control , Personal Satisfaction , Treatment Outcome , United Kingdom , Young Adult
15.
Environ Int ; 73: 423-33, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25244705

ABSTRACT

The aim of this review is to examine the relationship between genetically modified (GM) crops and health, based on histopathological investigations of the digestive tract in rats. We reviewed published long-term feeding studies of crops containing one or more of three specific traits: herbicide tolerance via the EPSPS gene and insect resistance via cry1Ab or cry3Bb1 genes. These genes are commonly found in commercialised GM crops. Our search found 21 studies for nine (19%) out of the 47 crops approved for human and/or animal consumption. We could find no studies on the other 38 (81%) approved crops. Fourteen out of the 21 studies (67%) were general health assessments of the GM crop on rat health. Most of these studies (76%) were performed after the crop had been approved for human and/or animal consumption, with half of these being published at least nine years after approval. Our review also discovered an inconsistency in methodology and a lack of defined criteria for outcomes that would be considered toxicologically or pathologically significant. In addition, there was a lack of transparency in the methods and results, which made comparisons between the studies difficult. The evidence reviewed here demonstrates an incomplete picture regarding the toxicity (and safety) of GM products consumed by humans and animals. Therefore, each GM product should be assessed on merit, with appropriate studies performed to indicate the level of safety associated with them. Detailed guidelines should be developed which will allow for the generation of comparable and reproducible studies. This will establish a foundation for evidence-based guidelines, to better determine if GM food is safe for human and animal consumption.


Subject(s)
Crops, Agricultural/toxicity , Gastrointestinal Tract/pathology , Plants, Genetically Modified/toxicity , Animals , Crops, Agricultural/genetics , Rats
16.
Neuroimage ; 102 Pt 2: 688-94, 2014 Nov 15.
Article in English | MEDLINE | ID: mdl-25175537

ABSTRACT

Stimulus visibility is associated with neural signals in multiple brain regions, ranging from visual cortex to prefrontal regions. Here we used functional magnetic resonance imaging (fMRI) to investigate to which extent the perceived visibility of a "low-level" grating stimulus is reflected in the brain activity in high-level brain regions. Oriented grating stimuli were presented under varying visibility conditions created by backward masking. Visibility was manipulated using four different stimulus onset asynchronies (SOAs), which created a continuum from invisible to highly visible target stimuli. Brain activity in early visual areas, high-level visual brain regions (fusiform gyrus), as well as parietal and prefrontal brain regions was significantly correlated with subjects' psychometric visibility functions. In addition, increased stimulus visibility was reflected in the functional coupling between low and high-level visual areas. Specifically, neuroimaging signals in the middle occipital gyrus were significantly more correlated with signals in the inferior temporal gyrus when subjects successfully perceived the target stimulus than when they did not. These results provide evidence that not only low-level visual but also high-level brain regions reflect visibility of low-level grating stimuli and that changes in functional connectivity reflect perceived stimulus visibility.


Subject(s)
Occipital Lobe/physiology , Temporal Lobe/physiology , Adult , Female , Humans , Magnetic Resonance Imaging , Male , Photic Stimulation , Visual Cortex/physiology , Young Adult
18.
Plant Dis ; 98(1): 155, 2014 Jan.
Article in English | MEDLINE | ID: mdl-30708619

ABSTRACT

White alder (Alnus rhombifolia) is a fast-growing tree native to the western United States and is planted frequently in landscapes. In September 2010, mature leaves of white alder with small, orange-yellow pustules were collected in a commercial nursery in Santa Cruz County, CA. Approximately 25 white alder trees were affected. Collected leaves were sent to the California Department of Food and Agriculture Plant Pest Diagnostics Laboratory. Young uredinial pustules were bullate, with urediniospores emerging from a single pore in the pustule. Spiny cells lined the ostiole. With age, pustules broke open to release more spores. Urediniospores were obovate to oval and measured from 14 to 20 × 27 to 41 µm (17.1 × 32.2 µm average, n = 62). Spores were uniformly echinulate and contained a nearly hyaline cell wall measuring from 1 to 2 µm (1.5 µm average) in thickness. A portion of the 28S ribosomal subunit (GenBank Accession No. KC313888) and the internal transcribed spacer regions (KC313889) were amplified and sequenced from DNA extracted from urediniospores using primers LR6 and rust2inv (1) and ITS1-F and ITS4-B (2), respectively. Our ITS sequence had 99% identity to GenBank accession EF564164, Melampsoridium hiratsukanum. In September 2011, white alder leaves with similar symptoms were collected from a commercial nursery in Santa Barbara County, CA. The spore morphology matched the white alder sample previously collected in Santa Cruz County, CA, in 2010. At that time, pathogenicity assays were conducted on three 1-year-old, 61-cm white alder trees planted in 3.8-liter pots. Six detached leaves with visible rust pustules were rubbed gently onto both the apical and distal side of moistened leaves of the healthy alders. Each infected leaf was used to inoculate a total of 6 to 10 healthy leaves by rubbing two leaves per tree before moving to the next tree. Leaves on three additional white alder trees were rubbed with healthy leaves as controls. Trees were incubated in a dew chamber for 3 days in darkness at 24°C, then placed in a growth chamber at 22°C with a 12-h photoperiod. Twelve days after inoculation, small lesions were visible on a few of the leaf undersides of each inoculated tree. Not all inoculated leaves developed pustules. No lesions developed on the control trees. M. hiratsukanum has been reported in Canada, Europe, and eastern Asia (3). There are no published reports of this rust in the United States, but there is an unpublished specimen from white alder in the USDA Systematic Mycology Herbarium (BPI 028048) collected from California in 1931, which was identified as M. hiratsukanum by G. B. Cummins using morphological criteria. We are unaware if older specimens of this rust exist because we were unable to search other herbaria in the United States. To the best of our knowledge, this rust has been present in California since 1931, but has only recently been found causing disease in nursery plants. There have been no reports of the serious foliar disease symptoms on trees in California wild lands as have been reported in Europe, presumably due to dry summer and fall seasons in white alder's natural habitat. References: (1) M. C. Aime. Mycoscience 47:112, 2006. (2) M. Gardes and T. D. Bruns. Mol. Ecol. 2:113, 1993. (3) J. Hatula et al. Mycologia 101:622, 2009.

19.
J Wound Care ; 22(12): 692, 694-6, 698, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24335893

ABSTRACT

This article outlines a strategic process for the evaluation of wound management products and the development of an algorithm as an implementation model for wound management. Wound management is an increasingly complex process given the variety of interactive dressings and other devices available. This article discusses the procurement process, access to wound management dressings and the use of wound management formularies within the UK. We conclude that the current commissioners of tissue viability within healthcare organisations need to adopt a proactive approach to ensure appropriate formulary evaluation and product selection, in order to achieve the most beneficial clinical and financial outcomes.


Subject(s)
Algorithms , Benchmarking/methods , Cost-Benefit Analysis/methods , Models, Statistical , State Medicine/economics , Wounds and Injuries/economics , Wounds and Injuries/therapy , Humans , United Kingdom , Wound Healing
20.
Nat Commun ; 4: 2261, 2013.
Article in English | MEDLINE | ID: mdl-23907321

ABSTRACT

Plasmodium falciparum resistance to artemisinin derivatives, the first-line antimalarial drug, drives the search for new classes of chemotherapeutic agents. Current discovery is primarily directed against the intracellular forms of the parasite. However, late schizont-infected red blood cells (RBCs) may still rupture and cause disease by sequestration; consequently targeting invasion may reduce disease severity. Merozoite invasion of RBCs requires interaction between two parasite proteins AMA1 and RON2. Here we identify the first inhibitor of this interaction that also blocks merozoite invasion in genetically distinct parasites by screening a library of over 21,000 compounds. We demonstrate that this inhibition is mediated by the small molecule binding to AMA1 and blocking the formation of AMA1-RON complex. Electron microscopy confirms that the inhibitor prevents junction formation, a critical step in invasion that results from AMA1-RON2 binding. This study uncovers a strategy that will allow for highly effective combination therapies alongside existing antimalarial drugs.


Subject(s)
Erythrocytes/parasitology , Malaria/parasitology , Parasites/metabolism , Plasmodium falciparum/metabolism , Protozoan Proteins/metabolism , Small Molecule Libraries/pharmacology , Animals , Antimalarials/analysis , Antimalarials/chemistry , Antimalarials/pharmacology , Artemisinins/pharmacology , Erythrocytes/drug effects , Erythrocytes/ultrastructure , Humans , Inhibitory Concentration 50 , Merozoites/drug effects , Merozoites/ultrastructure , Parasites/drug effects , Plasmodium falciparum/drug effects , Protein Binding/drug effects , Protein Kinase Inhibitors/pharmacology , Small Molecule Libraries/analysis , Small Molecule Libraries/chemistry , src-Family Kinases/antagonists & inhibitors , src-Family Kinases/metabolism
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