Publications by authors named "Yeo Jin Fei"

The prefrontal cortex is essential for executive functions such as decision-making and planning. There is also accumulating evidence that it is important for the modulation of pain. In this study, we investigated a possible role of prefrontal cortical calcium-independent phospholipase A (iPLA) in antinociception induced by the norepinephrine reuptake inhibitor (NRI) and tetracyclic (tricyclic) antidepressant, maprotiline.

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We report a case of an asymptomatic sclerosing odontogenic tumor in a 31-year-old woman. Radiologically, the tumor was well circumscribed, was predominantly radiolucent, and had a peripheral sclerotic margin. Histopathologically, the tumor showed small clusters, strands, and cords of small to medium-sized epithelial tumor cells in a sclerotic collagenous stroma.

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Background: The innate immune response (IMR) is critical for the oral mucosa due to their continuous exposure to various oral pathogens. Keratinocytes play important role in IMR. Therefore, to date, keratinocytes from different sources have been used as in vitro research model for the study of IMR.

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Background: Progression of diabetes-associated periodontal destruction and the roles of advanced glycation end products (AGEs) are investigated.

Methods: Diabetes was induced by streptozocotin injection, and periodontitis was induced via silk ligature placement with Porphyromonas gingivalis lipopolysaccharide injection in 64 Sprague-Dawley rats for 7 to 21 days. The quality of alveolar bone and attachment loss (AL) were measured by microcomputed tomography and histology.

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Functional neuroimaging studies have implicated the prefrontal cortex (PFCTX) in descending modulation of pain and the placebo effect. This study was performed to elucidate comprehensive PFCTX gene expression in an animal model of persistent trigeminal pain. Adult male C57BL/6J mice received facial carrageenan injection and showed sustained increase in nociceptive responses.

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Activation of the prefrontal cortex occurs during acute and chronic pain and models of experimental hyperalgesia. The present study was carried out to determine possible miRNA changes in the prefrontal cortex, after inflammatory pain induced by facial carrageenan injection in mice. miRNA microarray analyses showed significantly increased levels of miR-155 and miR-223 in the prefrontal cortex of carrageenan-injected mice.

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This study was carried out to elucidate the effects of calcium independent phospholipase A(2) (iPLA(2)) on mitochondrial function and exocytosis in neuroendocrine cells. iPLA(2) mRNA and protein were detected in cell lysates and mitochondria from PC12 cells. Treatment of cells with the iPLA(2) inhibitor, bromoenol lactone (BEL), resulted in reduction in the mitochondrial membrane potential.

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Phospholipases A(2) (PLA(2)) are enzymes which cleave the sn-2 ester bond in membrane phospholipids to release free fatty acids and lysophospholipids. The present study aimed to elucidate the expression profile of multiple secretory phospholipase A(2) (sPLA(2)) isoforms in the normal rat CNS with focus on sPLA(2)-IIA in the brainstem and spinal cord. Quantitative RT-PCR analysis showed that sPLA(2)-IB expression was low throughout the CNS, sPLA(2)-IIA expression was high in the brainstem and spinal cord, sPLA(2)-IIC expression was high in the cerebral neocortex, hippocampus and thalamus/hypothalamus, sPLA(2)-V expression was high in the olfactory bulb and cerebellum, and sPLA(2)-X was expressed at very low levels in the normal CNS.

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Secretory phospholipase A2 (sPLA2) activity is present in the CNS and the sPLA2-IIA isoform has been shown to induce exocytosis in cultured hippocampal neurons. However, little is known about possible contributions of various lysophospholipid species to exocytosis in neuroendocrine cells. This study was therefore carried out to examine the effects of several lysophospholipid species on exocytosis on rat pheochromocytoma-12 (PC12) cells.

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Utilizing a suitable combination of lactide and glycolide in a copolymer would optimize the degradation rate of a scaffold upon implantation in situ. Moreover, 3D printing technology enables customizing the shape of the scaffold to biometric data from CT and MRI scans. A previous in vitro study has shown that novel 3D-printed poly-lactic-co-glycolic acid (PLGA) scaffolds had good biocompatibility and mechanical properties comparable with human cancellous bone, while they could support proliferation and osteogenic differentiation of osteoblasts.

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The present study was carried out to examine global gene expression in the brainstem, in a mouse facial carrageenan injection model of orofacial pain. Mice that received facial carrageenan injection showed increased mechanical allodynia, demonstrated by increased responses to von Frey hair stimulation of the face. The brainstem was harvested at 3 days post-injection, corresponding to the time of peak responses, and analyzed by Affymetrix Mouse Genome 430 2.

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Objective: The purpose of this study was to investigate the current prescription pattern of oral healthcare professionals in the management of patients with trigeminal neuralgia at a local hospital.

Study Design: Data relating to a consecutive series of patients (n = 49) with typical trigeminal neuralgia was collected over a period of 6 months.

Results: Over half the subjects (70%) were using carbamazepine as the only form of medical therapy.

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A randomized clinical trial was carried out to compare the difference in the effects of using two different mouth rinses on healing after surgical removal of wisdom teeth. One mouth rinse contained chlorhexidine with alcohol whereas the other was chlorhexidine without alcohol. Twenty-one patients without any medical conditions underwent surgical removal of their 3rd molars by the same operator on both the sides.

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It was recently demonstrated that osteogenesis of hESC was more efficient without the initial embryoid body formation step. This study sought to further improve this direct differentiation culture system, by developing an autologous osteogenic-inducing culture supplement extracted from hESC-derived osteogenic cells themselves. A whole cell lysate was prepared from hESC-derived osteogenic cells, simply by exposure to deionized water followed by free-thawing and subsequent filtration.

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Unlabelled: Evidence-based medicine (EBM) is an emerging must-know topic for today's physicians. The present literature is inadequate in identifying the attitudes, practice, and educational needs and preferred interventions of EBM. The objectives of this survey were to identify a) the attitude toward and practice of EBM among physicians, b) perceived benefits of EBM in daily practice, c) barriers to EBM practice, and d) preferred educational interventions.

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Peroxynitrite (ONOO(-)) and species derived from it can oxidize and nitrate lipids, proteins and DNA leading to changes in signaling molecules. The present study was carried out to elucidate possible effects of CNS peroxynitrite in a mouse model of orofacial pain. Mice that received facial carrageenan injection + intracerebroventricular (i.

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Increases in several ceramide species have been shown by non-targeted lipid profiling (lipidomics) of the rat hippocampus after kainate lesions (Guan et al. FASEB J 20:1152-1161, 2006). This study was carried out to examine possible effects of ceramide species on exocytosis.

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This was a retrospective study of dentigerous cysts in people from the Singapore-Malaysian region. The purpose of this study was to present the clinicopathologic features of dentigerous cysts in the Oriental population and to compare these data with those from other reported studies. Biopsy records from 1981 to 1993 of 119 cases of dentigerous cysts from patients in Malaysia and Singapore showed that 36.

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The present study was carried out to determine the effects of central nervous free fatty acids, lysophospholipids, or platelet activating factor (PAF), in a mouse facial carrageenan injection model of orofacial pain. Mice that received intracerebroventricular (I.C.

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The present study was carried out to elucidate the distribution of calcium-independent phospholipase A(2) (iPLA(2)) in the normal monkey brain. iPLA(2) immunoreactivity was observed in structures derived from the telencephalon, including the cerebral neocortex, amygdala, hippocampus, caudate nucleus, putamen, and nucleus accumbens, whereas structures derived from the diencephalon, including the thalamus, hypothalamus and globus pallidus were lightly labeled. The midbrain, vestibular, trigeminal and inferior olivary nuclei, and the cerebellar cortex were densely labeled.

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The fusion of synaptic vesicles with the plasma membrane during exocytosis can be recorded by membrane capacitance measurements under voltage-clamp conditions. These measurements enable high time-resolution quantitation of exocytosis. The present study was carried out using the above technique to elucidate the effects of various polyunsaturated fatty acids on exocytosis in a neuroendocrine cell, the rat pheochromocytoma-12 (PC12) cell.

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The present study was carried out to elucidate the effect of a single episode of oxidative stress on pyramidal neurons of the rat hippocampus. A significant increase in the number of neurons that were immunolabeled for the toxic lipid peroxidation product, 4-hydroxynonenal (HNE) was observed in field CA3 of the hippocampus, at 1 day, 7 days and 14 days after intracerebroventricular injection of 1 microL of 5 mM ferrous ammonium citrate, compared to ammonium citrate injected controls at these time points. The number of HNE positive cells was fewer at 14 days, compared to 1 day, after ferrous ammonium citrate injection.

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The personal digital assistant (PDA) offers clinicians the ability to enter and manage clinical information at the point of care. The first part of this series examined the oral medicine and surgery resources available on the Internet. This article discusses the possibilities of PDA technology, in conjunction with the Internet, for oral maxillofacial surgeons to enhance their clinical practice.

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