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Tan K, Adie K, Tan R, McNabb A, Tang P. P197 Molecular detection and monitoring of disseminated Adenovirus infection in a hematopoietic stem cell transplant recipient by real-time PCR. Int J Antimicrob Agents 2009. [DOI: 10.1016/s0924-8579(09)70416-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Tan K, Anderson M, Krajden M, Petric M, Mak A, Naus M. O13 Mumps virus detection by PCR and culture during an outbreak in a highly unvaccinated population. Int J Antimicrob Agents 2009. [DOI: 10.1016/s0924-8579(09)70160-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Mirza H, Tan K. P249 Comparison, optimization and validation of high throughput in-vitro drug susceptibility microassays for the emerging protozoan pathogen Blastocystis. Int J Antimicrob Agents 2009. [DOI: 10.1016/s0924-8579(09)70468-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Tam X, Shiu S, Chow WS, Wong Y, Betteridge J, Tan K. Abstract: P1203 ATORVASTATIN INDUCES THE EXPRESSION OF SOLUBLE RECEPTOR FOR ADVANCED GLYCATION END PRODUCTS. ATHEROSCLEROSIS SUPP 2009. [DOI: 10.1016/s1567-5688(09)70310-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Beecroft R, Mujoomdar A, Patry G, Lo K, Kachura J, Jarvi K, Rajan D, Tan K, Sniderman K. Abstract No. 235: Short-Term Outcomes After Varicocele Repair by Embolization and Microsurgical Varicocelectomy: Implications for IVF Planning. J Vasc Interv Radiol 2009. [DOI: 10.1016/j.jvir.2008.12.229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Bent C, Rajan D, Simons M, Tan K, Beecroft R, Jaskolka J, Kachura J, Sniderman K. Abstract No. 122: Efficacy of Stent-Graft Placement for Salvage of Dysfunctional Arteriovenous Hemodialysis Fistulas. J Vasc Interv Radiol 2009. [DOI: 10.1016/j.jvir.2008.12.105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Tan K, Sniderman K, Rajan D, Kachura J, Jaskolka J, Simons M, Beecroft R. Abstract No. 363 EE: Endovascular Strategies in Difficult and Challenging Iliac Access During Aortic Stent Graft. Tips and Tricks with Current Non-Custom Devices. J Vasc Interv Radiol 2009. [DOI: 10.1016/j.jvir.2008.12.358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Xiong W, Lim JH, Ong SH, Tung NN, Liu J, Racoceanu D, Tan K, Chong A, Foong K. Automatic working area classification in peripheral blood smears without cell central zone extraction. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2009; 2008:4074-7. [PMID: 19163607 DOI: 10.1109/iembs.2008.4650104] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In this paper we study automatic classification of working areas in peripheral blood smears using image analysis and recognition methods. Such automatic classification can provide objective and reproducible quality control for the evaluation of smears and smear maker devices. However, research in this filed has drawn little attention. Existing methods either can not differentiate correctly different cell distributions or rely on the extraction of the central pallor zones in cells for counting, which are not always observable. In contrast, we do not rely on the pallor zone extraction thus on more general basis. We introduce two generic parameters to measure the goodness of working areas, one for the degree of overlap, and the other for the spatial occupancy. We also propose a cascading classification network for the classification of different areas. The effectiveness of our method has been tested on over 150 labeled images acquired from three malaria-infected Giemsa-stained blood smears using an oil immersion 100 x objective.
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Tan K, Roda R, Ostrow L, McArthur J, Nath A. PML-IRIS in patients with HIV infection: clinical manifestations and treatment with steroids. Neurology 2009; 72:1458-64. [PMID: 19129505 DOI: 10.1212/01.wnl.0000343510.08643.74] [Citation(s) in RCA: 247] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Progressive multifocal leukoencephalopathy (PML) is an opportunistic infection that develops in immunosuppressed patients with HIV infection. Paradoxically, some of these patients may develop PML during combined antiretroviral therapy in the setting of immune reconstitution. We describe the types of PML in relation to immune reconstitution inflammatory syndrome (IRIS) and the effects of steroid use in these patients. METHODS We performed a retrospective review of the literature (1998 to 2007) and of all HIV-infected patients diagnosed with PML-IRIS at Johns Hopkins Hospital (2004 to 2007). We recorded information on clinical features, microbiologic and virological analysis, neuroimaging, pathology, treatment, and outcome. RESULTS Of 54 patients with PML-IRIS, 36 developed PML and IRIS simultaneously (PML-s-IRIS) and 18 had worsening of preexisting PML (PML-d-IRIS) after the initiation of combined antiretroviral therapy. PML-IRIS developed between 1 week and 26 months after initiation of antiretroviral therapy. PML-d-IRIS patients developed IRIS earlier, had higher lesion loads on MRI of the brain, had shorter durations of survival, and had higher mortality rate compared to PML-s-IRIS patients. Twelve patients received treatment with steroids, of which five died and seven showed good neurologic recovery. Patients who survived had received steroids early after IRIS diagnosis for longer durations and had contrast enhancement on IRIS neuroimaging. CONCLUSIONS Immune reconstitution following initiation of combined antiretroviral therapy may lead to activation of an inflammatory response to detectable or latent JC virus infection. Early and prolonged treatment with steroids may be useful in these patients but requires further investigation.
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van der Leest K, Bogaard J, Rudolphus A, Tan K, van Tilburg A, Mannaerts G, Aerts J. Paraesophageal Hiatal Hernia-Induced Dyspnea. Respiration 2009; 78:105. [PMID: 17284893 DOI: 10.1159/000099333] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2007] [Indexed: 11/19/2022] Open
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Tan K, Hammond ER, Kerr D, Nath A. Fibrocartilaginous embolism: a cause of acute ischemic myelopathy. Spinal Cord 2008; 47:643-5. [DOI: 10.1038/sc.2008.135] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Hankey GJ, Algra A, Chen C, Wong MC, Cheung R, Wong L, Divjak I, Ferro J, de Freitas G, Gommans J, Groppa S, Hill M, Spence D, Lees K, Lisheng L, Navarro J, Ranawaka U, Ricci S, Schmidt R, Slivka A, Tan K, Tsiskaridze A, Uddin W, Vanhooren G, Xavier D, Armitage J, Hobbs M, Le M, Sudlow C, Wheatley K, Yi Q, Bulder M, Eikelboom JW, Hankey GJ, Ho WK, Jamrozik K, Klijn K, Koedam E, Langton P, Nijboer E, Tuch P, Pizzi J, Tang M, Antenucci M, Chew Y, Chinnery D, Cockayne C, Loh K, McMullin L, Smith F, Schmidt R, Chen C, Wong MC, de Freitas G, Hankey GJ, Loh K, Song S. VITATOPS, the VITAmins TO prevent stroke trial: rationale and design of a randomised trial of B-vitamin therapy in patients with recent transient ischaemic attack or stroke (NCT00097669) (ISRCTN74743444). Int J Stroke 2008; 2:144-50. [PMID: 18705976 DOI: 10.1111/j.1747-4949.2007.00111.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Epidemiological studies suggest that raised plasma concentrations of total homocysteine (tHcy) may be a common, causal and treatable risk factor for atherothromboembolic ischaemic stroke, dementia and depression. Although tHcy can be lowered effectively with small doses of folic acid, vitamin B(12) and vitamin B(6), it is not known whether lowering tHcy, by means of B vitamin therapy, can prevent stroke and other major atherothromboembolic vascular events. AIM To determine whether the addition of B-vitamin supplements (folic acid 2 mg, B(6) 25 mg, B(12) 500 microg) to best medical and surgical management will reduce the combined incidence of stroke, myocardial infarction (MI) and vascular death in patients with recent stroke or transient ischaemic attack (TIA) of the brain or eye. DESIGN A prospective, international, multicentre, randomised, double blind, placebo-controlled clinical trial. SETTING One hundred and four medical centres in 20 countries on five continents. SUBJECTS Eight thousand (6600 recruited as of 5 January, 2006) patients with recent (<7 months) stroke (ischaemic or haemorrhagic) or TIA (brain or eye). RANDOMISATION Randomisation and data collection are performed by means of a central telephone service or secure internet site. INTERVENTION One tablet daily of either placebo or B vitamins (folic acid 2 mg, B(6) 25 mg, B(12) 500 mug). PRIMARY OUTCOME The composite of stroke, MI or death from any vascular cause, whichever occurs first. Outcome and serious adverse events are adjudicated blinded to treatment allocation. SECONDARY OUTCOMES TIA, unstable angina, revascularisation procedures, dementia, depression. STATISTICAL POWER: With 8000 patients followed up for a median of 2 years and an annual incidence of the primary outcome of 8% among patients assigned placebo, the study will have at least 80% power to detect a relative reduction of 15% in the incidence of the primary outcome among patients assigned B vitamins (to 6.8%/year), applying a two-tailed level of significance of 5%. CONCLUSION VITATOPS aims to recruit and follow-up 8000 patients between 1998 and 2008, and provide a reliable estimate of the safety and effectiveness of folic acid, vitamin B(12), and vitamin B(6) supplementation in reducing recurrent serious vascular events among a wide range of patients with TIA and stroke throughout the world.
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Tan K, Patel S, Gandhi N, Chow F, Rumbaugh J, Nath A. Burden of neuroinfectious diseases on the neurology service in a tertiary care center. Neurology 2008; 71:1160-6. [PMID: 18838663 DOI: 10.1212/01.wnl.0000327526.71683.b7] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Neurologic infections have the potential to cause death and suffering. These disorders often go unrecognized or are misdiagnosed. There has yet not been a census of neurologic infections conducted in a hospital setting. We aimed to determine the burden of neurologic infections on the neurology service in a tertiary care center and identify challenges in the diagnosis and treatment of these infections. METHODS We reviewed retrospectively all inpatients diagnosed with any neuroinfectious disease evaluated at Johns Hopkins Medical Institutions between October 2004 and December 2005. We recorded information on hospital admission, clinical features, microbiologic analysis, neuroimaging, EEG, pathology, treatment, and outcome. RESULTS A total of 116 of 4,225 patients admitted to or consulted on by the neurology service were identified. Eighty percent of patients were aged between 18 and 65 years. Fifty-two patients were immunocompromised, of which 28 patients had HIV infection. Overall, 86 microbiologic agents were identified in 80 patients. The commonest causes were viral, followed by bacterial and fungal infections. However, 31% of patients remained without an identifiable microbiologic etiology. Hospitalization periods were long, with 43% of patients staying beyond 2 weeks. There was significant morbidity: 28% of patients required rehabilitation or long-term care, and 12% died. CONCLUSIONS Neurologic infections have a major socioeconomic impact because they result in prolonged hospitalizations, expensive diagnostic tests and treatments, and long-term debilitation or death in young patients. Though potentially curable conditions, the burden of undiagnosed infections remains high.
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Kandiah N, Tan K, Pan AB, Au WL, Venketasubramanian N, Tchoyoson Lim CC, Tan NC. Creutzfeldt-Jakob disease: which diffusion-weighted imaging abnormality is associated with periodic EEG complexes? J Neurol 2008; 255:1411-4. [PMID: 18575917 DOI: 10.1007/s00415-008-0934-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2007] [Revised: 02/10/2008] [Accepted: 03/07/2008] [Indexed: 11/28/2022]
Abstract
BACKGROUND Clinical diagnosis of CJD remains important due to lack of access to a genetic or histopathological diagnosis. Using current WHO criteria, diagnostic certainty can be increased from "possible" to "probable" CJD if periodic complexes are recorded on EEG. OBJECTIVE To study the correlation between patterns of MRI-DWI hyperintensity and typical EEG findings among patients with CJD. METHODS Demographics, clinical findings, MRI-DWI and EEG findings of CJD patients were retrospectively reviewed. RESULTS A total of 14 patients ranging in age from 35 to 81 years were identified. All had dementia and cerebellar ataxia. Psychiatric manifestations were seen in 5 patients. Seven patients had both cortical and striatal DWI changes, five had isolated cortical DWI changes and two had isolated striatal DWI changes. All twelve patients with cortical DWI changes also had periodic EEG changes. In ten, periodic EEG was recorded within seven days of the DWI. The two patients with isolated striatal DWI changes did not develop periodic EEG complexes despite serial EEG recordings, 40 and 88 days from their respective DWI scans. CONCLUSIONS Serial EEGs are not useful for patients with isolated striatal DWI hyperintensity but will increase diagnostic certainty from "possible" to probable" CJD for patients with cortical DWI hyperintensity.
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Kim Y, Quartey P, Volkart L, Hatzos C, Chang C, Nocek B, Cuff M, Osipiuk J, Tan K, Fan Y, Bigelow L, Maltseva N, Wu R, Borovilos M, Duggan E, Li H. Improving protein crystallization: a large-scale evaluation of protein reductive methylation. Acta Crystallogr A 2008. [DOI: 10.1107/s0108767308092271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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141
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Shaw PC, Ng AL, Zhang H, Wang J, Tan K, Au SN. Structure of influenza H5N1 nucleoprotein and its interaction with RNA. Acta Crystallogr A 2008. [DOI: 10.1107/s0108767308089496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Tan K, Yang MX, Radloff SE, Hepburn HR, Zhang ZY, Luo LJ, Li H. Dancing to different tunes: heterospecific deciphering of the honeybee waggle dance. Naturwissenschaften 2008; 95:1165-8. [DOI: 10.1007/s00114-008-0437-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2008] [Revised: 07/21/2008] [Accepted: 07/23/2008] [Indexed: 10/21/2022]
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Tan GM, Ti LK, Tan K, Lee T. A Comparison of Screen-based Simulation and Conventional Lectures for Undergraduate Teaching of Crisis Management. Anaesth Intensive Care 2008; 36:565-9. [DOI: 10.1177/0310057x0803600411] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In our institution, we introduced a screen-based simulator to our undergraduate lectures on medical crisis management. We hypothesised that this novel use of the screen-based simulator would be as effective as our conventional lectures. To test this we randomly divided medical students into two groups. Students in Group A were taught medical crisis management (heart failure and anaphylaxis) using a screen-based simulation program projected onto a shared screen, with a facilitator guiding the students through the scenarios. Simultaneously, students in Group B were lectured the same content without the screen-based simulation. Both groups were allotted exactly one hour. Several days later, students were tested on their management of anaphylaxis using the Human Patient Simulator. A blinded marker assessed them on diagnosis, resuscitation, specific treatment, call for help and for reassessment of the patient. Students also answered a questionnaire on their experience. Sixty-four students participated in the study. Both groups had similar overall scores. However, students in Group A scored better in the specific treatment category by a factor of 7.7. Students in both groups rated their learning experiences highly. This study showed that screen-based simulation was as effective as conventional lectures and might be even more effective in some areas.
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Irani F, Tan K. Abstract No. 250: Intervention of Long Segment SFA Occlusions – Is It Worthwhile? J Vasc Interv Radiol 2008. [DOI: 10.1016/j.jvir.2007.12.280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Tan K, Lim SA, Thomas A, Lim CT, Wong SY, Tan CB. Idiopathic hypertrophic pachymeningitis causing seizures. Eur J Neurol 2007; 15:e12-3. [PMID: 18093150 DOI: 10.1111/j.1468-1331.2007.02023.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Tan K, Guo YH, Nicolson SW, Radloff SE, Song QS, Hepburn HR. Honeybee (Apis cerana) foraging responses to the toxic honey of Tripterygium hypoglaucum (Celastraceae): changing threshold of nectar acceptability. J Chem Ecol 2007; 33:2209-17. [PMID: 18058178 DOI: 10.1007/s10886-007-9384-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2007] [Revised: 10/09/2007] [Accepted: 10/16/2007] [Indexed: 11/28/2022]
Abstract
To investigate honeybee foraging responses to toxic nectar, honey was collected from Apis cerana colonies in the Yaoan county of Yunnan Province, China, during June, when flowers of Tripterygium hypoglaucum were the main nectar source available. Pollen analysis confirmed the origin of the honey, and high-performance liquid chromatography showed the prominent component triptolide to be present at a concentration of 0.61 mug/g +/- 0.11 SD. In cage tests that used young adult worker bees, significantly more of those provided with a diet of T. hypoglaucum honey mixed with sugar powder (1:1) died within 6 d (68.3%) compared to control groups provided with normal honey mixed with sugar powder (15.8%). Honeybees were trained to visit feeders that contained honey of T. hypoglaucum (toxic honey) as the test group and honey of Vicia sativa or Elsholtzia ciliata as control groups (all honeys diluted 1:3 with water). Bees preferred the feeders with normal honey to those with toxic honey, as shown by significantly higher visiting frequencies and longer imbibition times. However, when the feeder of normal honey was removed, leaving only honey of T. hypoglaucum, the foraging bees returned to the toxic honey after a few seconds of hesitation, and both visiting frequency and imbibition time increased to values previously recorded for normal honey. Toxic honey thus became acceptable to the bees in the absence of other nectar sources.
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Morley S, Peck L, Tan K, Day R, Poertner H. Thermal niche, aerobic scope and temperature sensitivity: A latitudinal comparison. Comp Biochem Physiol A Mol Integr Physiol 2007. [DOI: 10.1016/j.cbpa.2007.01.523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Tan K, Cheang P, Ho IAW, Lam PYP, Hui KM. Nanosized bioceramic particles could function as efficient gene delivery vehicles with target specificity for the spleen. Gene Ther 2007; 14:828-35. [PMID: 17344903 DOI: 10.1038/sj.gt.3302937] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We have compared the ability of several nanosized bioceramic particles including negatively charged silica (SiO(2)), neutrally charged hydroxyapatite (HA) and positively charged zirconia (ZrO(2)) nanoparticles as non-viral vectors for efficient in vivo gene delivery. A mixture of highly monodispersed aqueous suspension of HA or SiO(2) nanoparticles, coated with protamine sulfate (PS), complexed efficiently with plasmid DNA and significantly enhanced transgene expression in vitro. In comparison, ZrO(2) nanoparticles gave poor transfection efficiency under similar conditions tested. It was also determined that, under the same conditions, PS-SiO(2)-DNA, but not PS-HA-DNA-nanoplexes, were able to mediate efficient transgene expression in vitro in the presence of 50% serum. Intraperitoneal injections of PS-SiO(2)-luciferase DNA nanoplexes targeted the highest level of transgene expression in the spleen of recipient mice that lasted for more than 48 h. Injection of PS-SiO(2)-pNGVL-hFLex-MUC-1 nanoplexes was able to mediate the production of Flt-3L in the sera of recipient mice. Simultaneously, the production of Flt-3L was accompanied by the stimulation of IL-2 and interferon-gamma (IFN-gamma). Most importantly, the injection of PS-SiO(2)-pNGVL-hFLex-MUC-1 nanoplexes could mount potent anti-tumour specific immune responses that led to the subsequent regression of parental tumor cells containing the muc-1 determinant.
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Tan K, Radloff SE, Li JJ, Hepburn HR, Yang MX, Zhang LJ, Neumann P. Bee-hawking by the wasp, Vespa velutina, on the honeybees Apis cerana and A. mellifera. Naturwissenschaften 2007; 94:469-72. [PMID: 17235596 DOI: 10.1007/s00114-006-0210-2] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2006] [Revised: 11/30/2006] [Accepted: 12/06/2006] [Indexed: 10/23/2022]
Abstract
The vespine wasps, Vespa velutina, specialise in hawking honeybee foragers returning to their nests. We studied their behaviour in China using native Apis cerana and introduced A. mellifera colonies. When the wasps are hawking, A. cerana recruits threefold more guard bees to stave off predation than A. mellifera. The former also utilises wing shimmering as a visual pattern disruption mechanism, which is not shown by A. mellifera. A. cerana foragers halve the time of normal flight needed to dart into the nest entrance, while A. mellifera actually slows down in sashaying flight manoeuvres. V. velutina preferentially hawks A. mellifera foragers when both A. mellifera and A. cerana occur in the same apiary. The pace of wasp-hawking was highest in mid-summer but the frequency of hawking wasps was three times higher at A. mellifera colonies than at the A. cerana colonies. The wasps were taking A. mellifera foragers at a frequency eightfold greater than A. cerana foragers. The final hawking success rates of the wasps were about three times higher for A. mellifera foragers than for A. cerana. The relative success of native A. cerana over European A. mellifera in thwarting predation by the wasp V. velutina is interpreted as the result of co-evolution between the Asian wasp and honeybee, respectively.
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Regier T, Paulsen J, Wright G, Coulthard I, Tan K, Sham TK, Blyth RIR. Commissioning of the Spherical Grating Monochromator Soft X-ray Spectroscopy Beamline at the Canadian Light Source. ACTA ACUST UNITED AC 2007. [DOI: 10.1063/1.2436101] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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