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1.
Spine Deform ; 9(4): 949-954, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33660241

RESUMEN

INTRODUCTION: Clinicians and patients must weigh the benefits of radiological imaging against the risks of radiation exposure in the diagnosis and treatment of scoliosis. This report aims to estimate the cumulative absorbed and equivalent dose of radiation in patients undergoing surgical treatment for scoliosis, and to present this as an estimated risk of cancer compared to background radiation levels. METHODS: Retrospective review of estimated absorbed dose on the Computerised Radiology Information System (CRIS®). Patients undergoing surgical correction of scoliosis (age ≤ 25) from August 2010 to August 2015 investigated. Estimated absorbed dose [milligrays (mGy)] recorded. Pedicle screws inserted using image intensification. Equivalent dose [millisieverts (mSv)] and additional cancer risk calculated from the National Research Council document 'Health risks from exposure to low levels of ionising radiation' (2006). RESULTS: 271 patients identified. Mean age 15 (range 2-25). Mean total absorbed dose 2136 mGy [standard deviation (SD) 1700 mGy]. Mean number of plain spine radiographs was 8 (SD 3) with total 1884 mGy exposure (SD 1609 mGy). Additional dose provided by CT (mean 0.17 episodes), plain chest and abdominal radiographs and image intensification. Mean number of image intensification episodes was 1.1 with mean estimated exposure 180 mGy (SD 238 mGy). Image intensification accounted for 8% of the estimated absorbed dose during treatment. Estimated mean effective dose delivered was 20.952 mSv equating to an additional cancer risk of 0.27-0.45%. CONCLUSION: Additional cancer risk from cumulative imaging is small and equivalent to approximately 8 years of natural background radiation. Use of image intensification for pedicle screw insertion is a minor contribution (8%) to the total patient dose.


Asunto(s)
Neoplasias , Escoliosis , Adolescente , Niño , Humanos , Dosis de Radiación , Estudios Retrospectivos , Escoliosis/diagnóstico por imagen , Escoliosis/cirugía , Tomografía Computarizada por Rayos X , Rayos X
3.
Phytother Res ; 34(8): 1902-1925, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32147928

RESUMEN

Tephrosia purpurea (L.) Pers. is a well-known plant in Ayurveda and named "Sarwa wranvishapaka" for its property to heal wounds. Traditionally, it is practiced for impotency, asthma, dyspepsia, hemorrhoids, syphilis gonorrhea, rheumatism, enlargement of kidney and spleen. It is an important component of herbal preparations like Tephroli and Yakrifti used to cure liver disorders. Various phytocompounds including pongamol, purpurin, purpurenone, tephrosin, bulnesol, tephrostachin, ß-sitosterol, and so on have been reported. Modern pharmacological studies have shown that the plant have wound healing, antileishmanial, anticarcinogenic, antimicrobial, antioxidant, hepatoprotective, antifertility, antispermatogenic, anti-diarrheal, diuretic, and insecticidal properties. Acetylcholinesterase inhibitory action reported from this plant aids its utilization for the development of drugs for Alzheimer's and dementia neurological disorders. Among the known active compounds of T. purpurea, tephrostachin is responsible for antiplasmodial activity, tephrosin, pongaglabol, and semiglabrin exerts antiulcer activity while quercetin, rutin, ß-sitosterol, and lupeol are mainly responsible for its anti-inflammatory and anti-cancer properties. From different toxicological studies, concentrations up to 2,000 mg/kg were considered safe. The present review comprehensively summarizes the ethnomedicine, phytochemistry, pharmacology, and toxicology of T. purpurea. Further research on elucidation of the structure-function relationship among active compounds, understanding of multi-target network pharmacology and clinical applications will intensify its therapeutic potential.


Asunto(s)
Medicina Ayurvédica/métodos , Medicina Tradicional/métodos , Plantas/química , Tephrosia/toxicidad , Humanos
4.
Endosc Ultrasound ; 8(6): 418-427, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31552915

RESUMEN

BACKGROUND AND OBJECTIVES: Currently, pancreatic cystic lesions (PCLs) are recognized with increasing frequency and have become a more common finding in clinical practice. EUS is challenging in the diagnosis of PCLs and evidence-based decisions are lacking in its application. This study aimed to develop strong recommendations for the use of EUS in the diagnosis of PCLs, based on the experience of experts in the field. METHODS: A survey regarding the practice of EUS in the evaluation of PCLs was drafted by the committee member of the International Society of EUS Task Force (ISEUS-TF). It was disseminated to experts of EUS who were also members of the ISEUS-TF. In some cases, percentage agreement with some statements was calculated; in others, the options with the greatest numbers of responses were summarized. RESULTS: Fifteen questions were extracted and disseminated among 60 experts for the survey. Fifty-three experts completed the survey within the specified time frame. The average volume of EUS cases at the experts' institutions is 988.5 cases per year. CONCLUSION: Despite the limitations of EUS alone in the morphologic diagnosis of PCLs, the results of the survey indicate that EUS-guided fine-needle aspiration is widely expected to become a more valuable method.

7.
Transl Vis Sci Technol ; 4(2): 2, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25767745

RESUMEN

PURPOSE: To demonstrate the use of a spectral-domain optical coherence tomography (SDOCT) integrated surgical microscope in glaucoma surgery. METHODS: An SDOCT system was used to interface directly with an ophthalmic surgical microscope, to allow real-time intraoperative SDOCT (iOCT) imaging during glaucoma procedures like phaco-trabeculectomy, Ahmed glaucoma valve (AGV) implantation, gonio-synechiolysis, and bleb needling. The various surgical steps during glaucoma surgeries where iOCT can be of potential help in guiding the surgeon were recorded. RESULTS: High-resolution, cross-sectional images of the relevant structures were achieved with the iOCT system in all procedures. The surgeon could determine the depth of the scleral dissection, the intrastomal bed, the path of the AGV tube in the eye, the release of peripheral anterior synechiae and the efficacy of needling with respect to breakage of loculations; most of these are technically 'blind' procedures, where the outcomes are determined postoperatively. Metallic instruments cast a shadow on tissues below, thereby restricting the use of the device in its current state. CONCLUSIONS: The iOCT system provided high quality, intraoperative, real-time imaging, which could possibly improve the safety and efficacy of the surgical procedures in glaucoma. Further studies and modifications to the iOCT are required to better understand and increase the uptake of this technology in daily practice. TRANSLATIONAL RELEVANCE: The iOCT, with further advancements in its technology, could potentially provide the surgeon both quantitative and qualitative, real-time depth and tissue proximity details, thus improving the safety and accuracy of glaucoma surgery.

9.
Eur J Endocrinol ; 153(6): 929-38, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16322400

RESUMEN

BACKGROUND: Lithium, clinically used in the treatment of bipolar disorders, is well known to induce thyroid growth. However, the mechanism involved is only incompletely characterized. Although it is conventionally believed that thyroid proliferation depends on the thyroid-stimulating hormone (TSH)/cAMP/cAMP response element binding protein (CREB) pathway, recent data indicate that Wnt/beta-catenin signalling may be of critical importance. In other cell types lithium activates canonical Wnt signalling by GSK-3beta inhibition, which in turn stabilizes cytosolic free beta-catenin. Here we investigated the potential modulation of Wnt/beta-catenin signalling under lithium treatment in primary and neoplastic human thyrocytes. METHODS: Primary (S18) and neoplastic (NPA, FTC133) thyrocytes treated with and without LiCl were analysed using Western blotting, immunoprecipitation, reporter-gene assay, MTT proliferation assay and transfection studies. RESULTS: LiCl dose-dependently inhibited GSK-3beta, stabilized free beta-catenin and inhibited beta-catenin degradation. Furthermore, LiCl altered the assembly of adherens junction by upregulating the E-cad-herin repressor, Snail, and downregulated E-cadherin expression. At a dose of 5 mM, LiCl significantly increased the proliferative potency of thyrocytes, which appeared to be mediated by beta-catenin, since nuclear beta-catenin stimulated T-cell factor/lymphoid enhancer factor (TCF/LEF)-mediated transcription and upregulated downstream targets like cyclin D1. To characterize the specificity of Wnt/beta-catenin-driven thyrocyte proliferation, we transfected primary thyrocytes and FTC133 cells with dominant negative TCF4 to block Wnt-dependent pathways or with dominant negative CREB to inhibit the TSH/cAMP cascade. In cells transfected with dominant negative CREB lithium-stimulated proliferation was unchanged whereas blocking Wnt/beta-catenin by dominant negative TCF4 reduced proliferation by approx. 50%. CONCLUSION: Our data indicate that Wnt/beta-catenin signalling is of major importance in the control of lithium-dependent thyrocyte proliferation.


Asunto(s)
Cloruro de Litio/farmacología , Transducción de Señal/efectos de los fármacos , Glándula Tiroides/efectos de los fármacos , Proteínas Wnt/fisiología , beta Catenina/fisiología , Western Blotting , Cadherinas/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Ciclina D1/biosíntesis , Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Glucógeno Sintasa Quinasa 3 beta , Humanos , Glándula Tiroides/citología , Neoplasias de la Tiroides/fisiopatología , Transfección
10.
Oncogene ; 24(13): 2144-54, 2005 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-15735754

RESUMEN

Stabilization of beta-catenin by inhibition of its phosphorylation is characteristic of an activation of the canonical Wnt/beta-catenin signaling pathway and is associated with various human carcinomas. It contrasts to an as yet incompletely characterized action of an alternative noncanonical Wnt signaling pathway on neoplastic transformation. The aim of the present study was to test the effects of a member of the noncanonical Wnt signaling pathway, Wnt-5a, in primary thyroid carcinomas and in thyroid carcinoma cell lines. Compared to normal tissue Wnt-5a mRNA expression was clearly increased in thyroid carcinomas. Immunohistochemically, a bell-shaped response was observed with low to undetectable levels in normal tissue and in anaplastic tumors whereas differentiated thyroid carcinomas showed strong positive immunostaining for Wnt-5a. Transfection of Wnt-5a in a thyroid tumor cell line FTC-133 was able to reduce proliferation, migration, invasiveness and clonogenicity in these cells. These effects of Wnt-5a are associated with membranous beta-catenin translocation and c-myc oncogene suppression and are mediated through an increase in intracellular Ca(2+) release, which via CaMKII pathways promotes beta-catenin phosphorylation. Specific inhibition of beta-catenin phosphorylation by W-7, a calmodulin inhibitor, or by KN-93, a CaMKII inhibitor, supports these findings whereas PKC inhibitors were without effect. This interaction occurs downstream of GSK-3 beta as no Wnt-5a effect was seen on the Ser(9) phosphorylation of GSK-3 beta. Our data are compatible with the hypothesis that Wnt-5a serves as an antagonist to the canonical Wnt-signaling pathway with tumor suppressor activity in differentiated thyroid carcinomas.


Asunto(s)
Genes Supresores de Tumor , Neoplasias de la Tiroides/patología , Proteínas Supresoras de Tumor/genética , División Celular , Línea Celular Tumoral , Movimiento Celular , Proteínas del Citoesqueleto/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intercelular/fisiología , Invasividad Neoplásica , Transporte de Proteínas , Proteínas Proto-Oncogénicas , Glándula Tiroides/fisiología , Transactivadores/metabolismo , Transfección , Proteínas Supresoras de Tumor/fisiología , Proteínas Wnt , Proteína Wnt-5a , beta Catenina
11.
Med J Malaysia ; 58(5): 717-22, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15190658

RESUMEN

BACKGROUND: The summary of various studies done looking at size selection of the laryngeal mask airway (LMA) in adults is that, selection based on sex is appropriate, and that both sizes 4 or 5 are adequate for adult females. However, in our local population these sizes may be too large especially the size 5 for adult females. OBJECTIVE: To determine the optimal size of LMA in Malaysian female adults. METHOD: 135 ASA 1 or 2 adult female patients coming for elective surgery, requiring general anaesthesia suitable for LMA insertion were randomised into 3 groups to receive either a size 3, 4 or 5 LMA. Optimal size of the LMA was assessed based on 4 parameters, the number of attempts at placement, the oropharyngeal leak pressure (OLP), fibre optic score and the percentage of the vocal cords seen. RESULTS: The 3 groups were demographically similar. There was no difference in the 3 groups in terms of number of attempts of placement, OLP and fibre-optic score. The percentage of vocal cords seen with the size 3 LMA was significantly less than for the size 4 and size 5 (p = 0.009). For the size 5 LMA group in 10/45 patients, the size 5 LMA was too big making it incorrectly positioned after successful insertion and in another 3/45 patients it was difficult to pass the size 5 LMA past the open mouth during insertion. There were no such problems with the size 3 or 4 LMA groups. CONCLUSION: The optimal size of LMA for the female Malaysian adult is size 4.


Asunto(s)
Máscaras Laríngeas/normas , Adulto , Femenino , Humanos , Malasia
12.
Pest Manag Sci ; 57(7): 620-4, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11464794

RESUMEN

Kolleru Lake is the largest natural freshwater lake in India. Sediment samples were collected at different locations from Kolleru Lake at different seasons in a year over a period of three years and analyzed for eight selected pesticides. In general, pesticides were present at all locations. The selected pesticides alpha-BHC, gamma-BHC, malathion, chlorpyrifos and endosulfan were present at higher concentrations than isodrin, dieldrin and p,p'-DDT. The concentrations of alpha-BHC, gamma-BHC malathion, chlorpyrifos, isodrin, endosulfan, dieldrin and p,p'-DDT in sediments were 1.2-388, 1.4-212, from below the minimum detection limit (BDL)-186, 1.1-292, BDL-38.6, BDL-206, BDL-128 and BDL-191 micrograms kg-1 dry weight, respectively. The aim of this study is to evaluate baseline data, to try to account for the concentration of pesticides in sediments and to discuss their potential to affect human beings and aquatic organisms.


Asunto(s)
Residuos de Plaguicidas/análisis , Contaminantes del Suelo/análisis , Contaminantes del Agua/análisis , Ecosistema , Endosulfano/análisis , Endosulfano/toxicidad , Sedimentos Geológicos/análisis , Hidrocarburos Clorados/análisis , Hidrocarburos Clorados/toxicidad , India , Compuestos Organotiofosforados/análisis , Compuestos Organotiofosforados/toxicidad , Residuos de Plaguicidas/química
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