Publications by authors named "Panet H"

Background Climate change adversely affects human health, resulting in higher demand for health care services. However, the impact of climate-related environmental exposures on medical imaging utilization is currently unknown. Purpose To determine associations of short-term exposures to ambient heat and particulate air pollution with utilization of emergency department medical imaging.

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Climate change adversely affects the well-being of humans and the entire planet. A planetary health framework recognizes that sustaining a healthy planet is essential to achieving individual, community, and global health. Radiology contributes to the climate crisis by generating greenhouse gas (GHG) emissions during the production and use of medical imaging equipment and supplies.

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Adolescents and young adults (AYAs) with cancer aged 15-39 years have unique psychosocial, informational, and medical concerns compared to their older adult and pediatric counterparts. Recognizing the gaps in young adult cancer care, an AYA program was launched at a large tertiary cancer center to optimize the AYA cancer care experience. This article describes the contributions of a clinical nurse specialist in AYA program development.

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University Health Network has been working to become a high-reliability organization, with a focus on safe, quality patient care. In response, the Medical Affairs Department has implemented several strategic initiatives to drive accountability, quality improvement and engagement with our physician population. One of these initiatives, the Physician Quality Improvement Initiative (PQII) is a physician-led project designed to provide active medical staff, in collaboration with their physician department chiefs, a comprehensive approach to focused and practical quality improvement in their practice.

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One of the main limitations of the highly used cancer imaging technique, PET-CT, is its inability to distinguish between cancerous lesions and post treatment inflammatory conditions. The reason for this lack of specificity is that [(18)F]FDG-PET is based on increased glucose metabolic activity, which characterizes both cancerous tissues and inflammatory cells. To overcome this limitation, we developed a nanoparticle-based approach, utilizing glucose-functionalized gold nanoparticles (GF-GNPs) as a metabolically targeted CT contrast agent.

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Phase retrieval is a well-established method for the recovery of an object wave from its magnitude-only measurements, with applications in fields such as material science, biology, and astronomy. In order to guarantee a stable and global solution for phase retrieval, measurement diversity is frequently used. However, this process requires taking several measurements, which hinders some of the advantages of phase retrieval compared with interferometric techniques.

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4'-6-Diamidino-2-phenylindole is a fluorescent dye commonly used to visualize deoxyribonucleic acid or cell nuclei in fixed cell preparations, and is often used together with fluorescein or green fluorescent protein, which can be excited without exciting 4'-6-Diamidino-2-phenylindole. It is assumed that when using typical fluorescein or green fluorescent protein filter cubes, 4'-6-Diamidino-2-phenylindole will not be observed. In this paper, we show that following observation of 4'-6-Diamidino-2-phenylindole using UV or violet excitation, it may become sensitive to the blue/cyan excitation used in fluorescein/green fluorescent protein filter cubes.

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Background: Human bone marrow multipotent mesenchymal stromal cells (hMSC), because of their capacity of multipotency, may provide an unlimited cell source for cell replacement therapy. The purpose of this study was to assess the developmental potential of hMSC to replace the midbrain dopamine neurons selectively lost in Parkinson's disease.

Methods: Cells were isolated and characterized, then induced to differentiate toward the neural lineage.

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Strategies of cell therapy for the treatment of Parkinson's disease (PD) are focused on replacing damaged neurons with cells to restore or improve function that is impaired due to cell population damage. In our studies, we used mesenchymal stromal cells (MSCs) from mouse bone marrow. Following our novel neuronal differentiation method, we found that the basic cellular phenotype changed to cells with neural morphology that express specific markers including those characteristic for dopaminergic neurons, such as tyrosine hydroxylase (TH).

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Parkinson's disease is characterized by the loss of dopaminergic neurons in the substantia nigra. Attempted replacement of these neurons by stem cells has proved inconclusive. Bone marrow mesenchymal stem cells (MSC) are multipotent, differentiating into a variety of cells, including neuron-like cells.

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It is believed that oxidative stress (OS) plays an important role in the loss of dopaminergic nigrostriatal neurons in Parkinson's disease (PD) and that treatment with antioxidants might be neuroprotective. However, most currently available antioxidants cannot readily penetrate the blood brain barrier after systemic administration. We now report that AD4, the novel low molecular weight thiol antioxidant and the N-acytel cysteine (NAC) related compound, is capable of penetrating the brain and protects neurons in general and especially dopaminergic cells against various OS-generating neurotoxins in tissue cultures.

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Mesenchymal stem cells in the adult bone marrow are differentiated to connective tissue, muscle, bone, cartilage, and fat cells. Recent studies in cultures, animal models, and humans demonstrated the plasticity of these cells and their capacity to express neuronal markers. However, questions were raised as to whether the neuronal phenotypes reflect transient changes or even fusion with neurons.

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Recent studies suggest that glutamate neurotoxicity is involved in the pathogenesis of multiple sclerosis (MS), and that treatment with glutamate receptor (AMPA/kainate) antagonists inhibits experimental autoimmune encephalomyelitis (EAE), the conventional model of MS. Therefore, we examined whether riluzole, an inhibitor of glutamate transmission, affects the pathogenesis and clinical features of MS-like disease in myelin oligodendrocyte glycoprotein (MOG)-induced EAE in mice. Here we report that riluzole (10 mg/kgx2/day, i.

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Glatiramer acetate (GA) is efficacious in reducing demyelinating-associated exacerbations in patients with relapsing-remitting multiple sclerosis (RRMS) and in several experimental autoimmune encephalomyelitis (EAE) models. Here we report that GA reduced the clinical and pathological signs of mice in chronic EAE induced by myelin oligodendrocyte glycoprotein (MOG). GA-treated mice demonstrated only mild focal inflammation, and less demyelination, compared with controls.

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The exact pathogenesis of neuronal death following bleeding in brain parenchyma is still unknown. Hemoglobin (Hb) toxicity has been postulated to be one of the underlying mechanisms. The purpose of this study was to examine the possible contribution to neurotoxicity of each of the Hb compounds and to characterize the death pathway.

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Multiple sclerosis (MS) is an inflammatory disease of the central nervous system (CNS) characterized by destruction of myelin. Recent studies have indicated that axonal damage is involved in the pathogenesis of the progressive disability of this disease. To study the role of axonal damage in the pathogenesis of MS-like disease induced by myelin oligodendrocyte glycoprotein (MOG), we compared experimental autoimmune encephalomyelitis (EAE) in wild-type (WT) and transgenic mice expressing the human bcl-2 gene exclusively in neurons under the control of the neuron-specific enolase (NSE) promoter.

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The etiology of Parkinson's disease is still unknown, though current investigations support the notion of the pivotal involvement of oxidative stress in the process of neurodegeneration in the substantia nigra (SN). In the present study, we investigated the molecular mechanisms underlying cellular response to a challenge by dopamine, one of the local oxidative stressors in the SN. Based on studies showing that nuclear factor kappa B (NF-kappaB) is activated by oxidative stress, we studied the involvement of NF-kappaB in the toxicity of PC12 cells following dopamine exposure.

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The purpose of this study was to examine the effects of 3-O-methylation by catechol-O-methyltransferase (COMT) on the toxicity of levodopa in neuronal cultures. High concentrations of levodopa are toxic in vitro. Therefore, there is concern that long-term treatment with levodopa in patients with Parkinson's disease might accelerate the rate of degeneration of nigrostriatal neurons.

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1. Degeneration of nigrostriatal dopaminergic neurons is the major pathogenic substrate of Parkinson's disease (PD). It is assumed that the lethal trigger is the accumulation of oxidative reactive species generated during metabolism of the natural neurotransmitter dopamine.

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It is currently believed that excessive oxidant stress induced by metabolism of dopamine (DA), plays a major role in the pathogenesis of the selective nigrostriatal neuronal loss in Parkinson's disease. We recently showed that the neurotransmitter DA, in physiological concentrations, is capable of initiating apoptosis in cultured, post-mitotic sympathetic neurons. Bcl-2 is a proto-oncogene that blocks apoptosis.

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The effects of a series of D- and L-amino acid alcohols on the proliferation and phenotypic expression of B16 mouse melanoma cells were evaluated. B16 melanoma cells were incubated for different time intervals in the presence of D- or L-phenylalaninol (PHE), D- or L-alaninol (AL), D- or L-leucinol (LE), L-histidinol (HIS), L-tyrosinol (TYR) and L-methioninol (MET). All agents, including the D or L configuration, induced an anti-proliferative effect, although of considerably different magnitude.

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