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Synthesis and Characterization of the Platinum-Substituted Keggin Anion ?-H2SiPtW11O40(4-)
Inorg Chem
PUBLISHED: 11-20-2014
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Acidification of an aqueous solution of K8SiW11O39 and K2Pt(OH)6 to pH 4 followed by addition of excess tetramethylammonium (TMA) chloride yielded a solid mixture of TMA salts of H2SiPtW11O40(4-) (1) and SiW12O40(4-) (2). The former was separated from the latter by extraction into an aqueous solution and converted into tetra-n-butylammonium (TBA) and potassium salts TBA-1 and K-1. The ?-H2SiPtW11O40(4-) was identified as a monosubstituted Keggin anion using elemental analysis, IR spectroscopy, X-ray crystallography, electrospray ionization mass spectrometry, (195)Pt NMR spectroscopy, (183)W NMR spectroscopy, and (183)W-(183)W 2D INADEQUATE NMR spectroscopy. Both TBA-1 and K-1 readily cocrystallized with their unsubstituted Keggin anion salts, TBA-2 and K-2, respectively, providing an explanation for the historical difficulty of isolating certain platinum-substituted heteropolyanions in pure form.
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Asymmetric Hetero-Diels-Alder Reaction of Diazenes Catalyzed by Chiral Silver Phosphate: Water Participates in the Catalysis and Stereocontrol.
Org. Lett.
PUBLISHED: 11-20-2014
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The chiral silver phosphate was confirmed to efficiently catalyze a highly regio- and enantioselective hetero-Diels-Alder reaction of diazenes to furnish piperazine derivatives in high yields and excellent ee values. DFT calculations revealed that the water molecule participates in the catalysis by coordination to silver phosphate and also found that the hydroxy group of 1-hydroxy-2,3-hexadiene not only formed a hydrogen bond with the oxygen of phosphate but also coordinated to the Ag(I) to simultaneously stabilize the transition states and control the regioselectivity.
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Enhancement of the field emission from the TiO2 nanotube arrays by reducing in a NaBH4 solution.
ACS Appl Mater Interfaces
PUBLISHED: 11-20-2014
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A mass of oxygen vacancies are successfully introduced into TiO2 nanotube arrays using low-cost NaBH4 as a reductant in a liquid-phase environment. By controlling and adjusting the reduction time over the range of 0-24 h, the doping concentration of the oxygen vacancy realizes controllable and eventually reaches saturation. Meanwhile, the thermal stability of oxygen vacancies is also investigated, indicating that part of oxygen vacancies remain stable up to 250 °C. In addition, this liquid-phase reduction strategy significantly lowers the requirements of instruments and cost. More interesting, reduced TiO2 nanotube arrays show drastically enhanced field emission performances including substantially decreased turn-on field from 25.01 to 2.65 V/?m, a high current density of 3.5 mA/cm2 at 7.2 V/?m and an excellent field emission stability and repeatability. These results are attributed to the oxygen vacancies obtained by reducing in NaBH4 solution, resulting in a reduced effective work function and an increased conductivity.
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The Analysis of Neurovascular Remodeling in Entorhino-hippocampal Organotypic Slice Cultures.
J Vis Exp
PUBLISHED: 11-20-2014
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Ischemic brain injury is among the most common and devastating conditions compromising proper brain function and often leads to persisting functional deficits in the affected patients. Despite intensive research efforts, there is still no effective treatment option available that reduces neuronal injury and protects neurons in the ischemic areas from delayed secondary death. Research in this area typically involves the use of elaborate and problematic animal models. Entorhino-hippocampal organotypic slice cultures challenged with oxygen and glucose deprivation (OGD) are established in vitro models which mimic cerebral ischemia. The novel aspect of this study is that changes of the brain blood vessels are studied in addition to neuronal changes and the reaction of both the neuronal compartment and the vascular compartment can be compared and correlated. The methods presented in this protocol substantially broaden the potential applications of the organotypic slice culture approach. The induction of OGD or hypoxia alone can be applied by rather simple means in organotypic slice cultures and leads to reliable and reproducible damage in the neural tissue. This is in stark contrast to the complicated and problematic animal experiments inducing stroke and ischemia in vivo. By broadening the analysis to include the study of the reaction of the vasculature could provide new ways on how to preserve and restore brain functions. The slice culture approach presented here might develop into an attractive and important tool for the study of ischemic brain injury and might be useful for testing potential therapeutic measures aimed at neuroprotection.
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Lack of association between DSCAM gene polymorphisms and adolescent idiopathic scoliosis susceptibility in a Chinese Han population.
J Back Musculoskelet Rehabil
PUBLISHED: 11-20-2014
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In a recent genome wide association study, polymorphisms in the DSCAM and CNTNAP2 genes were reported to be related with susceptibility of AIS. Consequently, further replication studies are warranted in other populations due to ethnic difference in genetic background.OBJECTIVE: To explore whether single nucleotide polymorphisms (SNPs) of DSCAM (rs2222973) and CNTNAP2 (rs11770843) genes are associated with the susceptibility and curve severity of AIS in a Chinese Han population.METHODS: A total of 648 AIS patients and 573 age- and sex-matched healthy adolescents in rs2222973 were recruited, and in rs11770843 there were 100 AIS patients and 100 age- and sex-matched healthy adolescents included in present study. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis was repeatedly carried out to verify the linkage of AIS with SNPs rs2222973 in the DSCAM gene and rs11770843 in the CNTNAP2 gene. Case-control and case-only studies were respectively performed to define the contribution of the DSCAM gene polymorphisms to predisposition and disease severity of AIS.
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Proton energy optimization and reduction for intensity-modulated proton therapy.
Phys Med Biol
PUBLISHED: 10-08-2014
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Intensity-modulated proton therapy (IMPT) is commonly delivered via the spot-scanning technique. To 'scan' the target volume, the proton beam is controlled by varying its energy to penetrate the patient's body at different depths. Although scanning the proton beamlets or spots with the same energy can be as fast as 10-20?m?s(-1), changing from one proton energy to another requires approximately two additional seconds. The total IMPT delivery time thus depends mainly on the number of proton energies used in a treatment. Current treatment planning systems typically use all proton energies that are required for the proton beam to penetrate in a range from the distal edge to the proximal edge of the target. The optimal selection of proton energies has not been well studied. In this study, we sought to determine the feasibility of optimizing and reducing the number of proton energies in IMPT planning. We proposed an iterative mixed-integer programming optimization method to select a subset of all available proton energies while satisfying dosimetric criteria. We applied our proposed method to six patient datasets: four cases of prostate cancer, one case of lung cancer, and one case of mesothelioma. The numbers of energies were reduced by 14.3%-18.9% for the prostate cancer cases, 11.0% for the lung cancer cases and 26.5% for the mesothelioma case. The results indicate that the number of proton energies used in conventionally designed IMPT plans can be reduced without degrading dosimetric performance. The IMPT delivery efficiency could be improved by energy layer optimization leading to increased throughput for a busy proton center in which a delivery system with slow energy switch is employed.
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T1 Pelvic Angle (TPA): A New Predictor for Postoperative Sagittal Balance and Clinical Outcomes in Adult Scoliosis.
Spine
PUBLISHED: 10-02-2014
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Study Design. A retrospective radiographic study.Objective. To compare the prediction abilities of TPA and other parameters for postoperative sagittal balance, and investigate the relationships betweenthese parameters and health-related quality of life(HRQOL).Summary of Backgroud Data. Using SVA to assess sagittal alignment fails to take account the pelvic compensation. A new parameter -T1 pelvic angle (TPA) has been recommended to represent the global sagittal balance of adult scoliosis.Methods. A retrospective review was performed on patients with adult scoliosis undergoing correction surgery from May 2009 to March 2013. The Spearman rho was used to determine the correlations between the radiographic parameters (pre-operative, postoperative and changes) and overall ODI scores, VAS and SRS-22.Results. Significant correlations were found between the changes of TPA and the changes of LL, PT, SS, PI, SVA, SSA, ODI, VAS, SRS-22 and PSO degrees (P<0.05). The changes of SVA were significantly related to the changes of LL, TPA, C7/SFD, ODI, VAS, SRS-22 (P<0.05) but not PSO degrees (P>0.05). Significant correlations were found between the changes of SSA and the changes of TLK, TPA, ODI, VAS, SRS-22 and PSO degrees (P<0.05). The changes of C7/SFD were significantly related to the changes of SVA (P<0.05), but not the changes of ODI, VAS, SRS-22 or PSO degrees (P>0.05).Conclusion. TPA could better reflect the postoperative changes of sagittal alignment and HRQOL for patients with adult scoliosis. Moreover, the changes of TPA are strongly correlated to the osteotomy degrees for PSO and, TPA could be used as a reference parameter in surgical planning.
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Are there gender differences in sagittal spinal pelvic inclination before and after the adolescent pubertal growth spurt?
Eur Spine J
PUBLISHED: 09-04-2014
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Significant progression of spinal deformity could occur during the peak of pubertal growth in adolescent idiopathic scoliosis (AIS). Gender differences in spinal and vertebral inclination have been reported in asymptomatic young adults and are thought to affect the risk of curve progression in male and female AIS. The present study aimed to investigate whether there were gender differences in the sagittal spinal-pelvic profile and whether any differences occurred before or developed during the normal pubertal growth spurt.
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Developmental changes in children's understanding of horizontal projectile motion.
Int J Psychol
PUBLISHED: 09-03-2014
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This study investigated 5- to 13-year-old children's performance in solving horizontal projectile motion problems, in which they predicted the trajectory of a carried object released from a carrier in three different contexts. The results revealed that 5- and 8-year-olds' trajectory predictions were easily distracted by salient contextual features (e.g. the relative spatial locations between objects), whereas a proportion of 11- and 13-year-olds' performance suggested the engagement of the impetus concept in trajectory prediction. The impetus concept is a typical misconception of inertial motion that assumes that motion is caused by force. Children's performance across ages suggested that their naïve knowledge of projectile motion was neither well-developed and coherent nor completely fragmented. Instead, this study presented the dynamic process in which children with age gradually overcame the influences of contextual features and consistently used the impetus concept across motion problems.
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Transmissible gastroenteritis virus and porcine epidemic diarrhoea virus infection induces dramatic changes in the tight junctions and microfilaments of polarized IPEC-J2 cells.
Virus Res.
PUBLISHED: 08-27-2014
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Viral infection converts the normal constitution of a cell to optimise viral entry, replication, and virion production. These conversions contain alterations or disruptions of the tight and adherens junctions between cells as part of their pathogenesis, and reorganise cellular microfilaments that initiate, sustain and spread the viral infections and so on. Using porcine epidemic diarrhoea virus (PEDV), transmissible gastroenteritis virus (TGEV) and a model of normal intestinal epithelial cells (IPEC-J2), we researched the interaction between tight and adherens junctions and microfilaments of IPEC-J2 cells with these viruses. In our work, the results showed that IPEC-J2 cells were susceptible to TGEV and PEDV infection. And TGEV could impair the barrier integrity of IPEC-J2 cells at early stages of infection through down-regulating some proteins of tight and adherens junctions, while PEDV cloud cause a slight of damage in the integrity of epithelial barrier. In addition, they also could affect the microfilaments remodelling of IPEC-J2 cells, and the drug-interfered microfilaments could inhibit viral replication and release. Furthermore, PEDV+TGEV co-infection was more aggravating to damage of tight junctions and remodelling of microfilaments than their single infection. Finally, the PEDV and TGEV infection affected the MAPK pathway, and inhibition of MAPK pathway regulated the changes of tight junctions and microfilaments of cells. These studies provide a new insight from the perspective of the epithelial barrier and microfilaments into the pathogenesis of PEDV and TGEV.
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C-H functionalization/asymmetric Michael addition cascade enabled by relay catalysis: metal carbenoid used for C-C bond formation.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 08-21-2014
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A combination of either ruthenium(II) or rhodium(II) complexes and quinine-derived squaramide enables 3-diazooxindoles, indoles, and nitroalkenes to undergo highly efficient asymmetric three-component reactions, thus affording optically active 3,3'-bis(indole)s through a consecutive C-C bond-forming sequence, which turned out to be applicable to the facile total synthesis of (-)-folicanthine.
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Chiral Counteranion Strategy for Asymmetric Oxidative C(sp(3) )?H/C(sp(3) )?H Coupling: Enantioselective ?-Allylation of Aldehydes with Terminal Alkenes.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 08-13-2014
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The first enantioselective ?-allylation of aldehydes with terminal alkenes has been realized by combining asymmetric counteranion catalysis and palladium-catalyzed allylic C?H activation. This method can tolerate a wide scope of ?-branched aromatic aldehydes and terminal alkenes, thus affording allylation products in high yields and with good to excellent levels of enantioselectivity. Importantly, the findings suggest a new strategy for the future creation of enantioselective C?H/C?H coupling reactions.
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Alkyne mechanochemistry: putative activation by transoidal bending.
Chem. Commun. (Camb.)
PUBLISHED: 08-06-2014
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We investigated the use of mechanical stress to bend carbon-carbon triple bonds. Formation of an isoquinoline after reaction with a benzyl azide trap points towards a nucleophilic addition mechanism, differentiating mechanochemical trans-bending of ? bonds from the typical reactivity observed for cisoidal bending of triple bonds in strained cyclic alkynes.
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[Abnormal growth of spine in patients with adolescent idiopathic thoracic scoliosis].
Zhonghua Wai Ke Za Zhi
PUBLISHED: 07-19-2014
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To investigate if the growth patterns of the spine and pelvis are consistent in adolescent idiopathic scoliosis (AIS) patients with single thoracic curves.
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Gold-catalyzed [1,5]-hydride shift onto unactivated alkynes to trigger an intermolecular Diels-Alder reaction.
Org. Lett.
PUBLISHED: 07-02-2014
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A [1,5]-hydride shift of sp(3) C-H onto an unactivated carbon-carbon triple bond catalyzed by a gold(I) complex enabled N-propargylisoindolines to be latent dienes and therefore triggered an intermolecular Diels-Alder reaction with dienophiles. This protocol provides an atom-economical and straightforward approach to access a wide range of polycyclic skeletons in high yields and with excellent diastereoselectivities from easily accessible molecules.
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Syrinx resolution is correlated with the upward shifting of cerebellar tonsil following posterior fossa decompression in pediatric patients with Chiari malformation type I.
Eur Spine J
PUBLISHED: 06-23-2014
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Chiari malformation type I (CMI) is characterized by deformed hindbrain. This study aimed to quantitatively evaluate the alterations in position of hindbrain after Posterior fossa decompression (PFD), and to identify the factors associated with syrinx resolution in pediatric patients with CMI.
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Reconstruction of Penile Urethra With the 3-Dimensional Porous Bladder Acellular Matrix in a Rabbit Model.
Urology
PUBLISHED: 06-20-2014
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To evaluate the effect of reconstruction of penile urethra with the 3-dimensional (3-D) porous bladder acellular matrix (BAM) in a rabbit model.
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Global gene expression profiling identifies ALDH2, CCNE1 and SMAD3 as potential prognostic markers in upper tract urothelial carcinoma.
BMC Cancer
PUBLISHED: 06-16-2014
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Current knowledge about the molecular properties and prognostic markers of upper tract urothelial carcinoma (UTUC) is sparse and often based on bladder urothelial carcinoma (UC), which is thought to share common risk factors with UTUC. However, studies have suggested that differences exist regarding tumor behavior and molecular biology of these cancers, comprehensive investigations are needed to guide the clinical management of UTUC. In recent years, massively parallel sequencing has allowed insights into the biology of many cancers, and molecular prognostic markers based on this approach are rapidly emerging. The goal of this study was to characterize the gene expression patterns of UTUC using massively parallel sequencing, and identify potential molecular markers for prognosis in patients with UTUC.
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Palladium(II)/Lewis acid synergistically catalyzed allylic C-H olefination.
Org. Lett.
PUBLISHED: 06-12-2014
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The first allylic C-H olefination with ?-diazo esters synergistically catalyzed by a palladium(II) complex and (salen)CrCl has been established to directly generate conjugated polyene derivatives in moderate to high yields and with excellent stereoselectivities.
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Asymmetric organocatalysis combined with metal catalysis: concept, proof of concept, and beyond.
Acc. Chem. Res.
PUBLISHED: 06-09-2014
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Asymmetric catalysis has been considered to be the most intriguing means for building collections of functionalized optically active compounds. In particular, metal and organocatalysis have been well established to allow many fundamentally different reactions. Metal catalysis has enabled the participation of a much broader scope of chemical bonds in organic transformations than are allowed by organocatalysis, while organocatalysis permits a broader scope of functional groups to undergo a diverse range of enantioselective transformations, individually, simultaneously, or sequentially. Theoretically, the combination of organocatalysts and metal complexes could probably render new transformations through the simultaneous or sequential activation and reorganization of multiple chemical bonds if the superior features of both the catalysts are adopted. In 2001, both our research group and Takemoto's group separately described an asymmetric allylation of glycine imino esters with allyl acetate catalyzed by palladium complexes and chiral ammonium salts. In these cases, the oxidative addition of palladium complexes to allyl acetate formed the ?-allylic fragments, while the chiral ammonium salts were actually responsible for controlling the stereoselectivity. These reactions in fact marked the beginning of asymmetric organo/metal combined catalysis. Since then, asymmetric organocatalysis combined with metal catalysis, including cooperative catalysis, relay catalysis, and sequential catalysis, has been a versatile concept for the creation of unknown organic transformations. Sequential catalysis describes a one-pot reaction involving two or more incompatible catalytic cycles. Alternatively, cooperative and relay catalyses require high compatibility of principally distinct catalysts and will be the focus of this Account. The catalysts in cooperative catalytic reactions must be able to simultaneously and individually activate both substrates to drive a bond-forming reaction, while relay catalysis is basically defined as a cascade process in which two or more sequential bond-forming transformations are independently catalyzed by distinct catalysts. In the past decade, we have discovered a variety of binary catalytic systems consisting of metals, including Rh(II), Pd(0), Au(I), and Mg(II), and chiral organocatalysts, including chiral phosphoric acids and quinine-based bifunctional molecules, for cooperative catalysis and relay catalysis, allowing the accomplishment of many unprecedented asymmetric transformations. In this Account, these achievements will be summarized, particularly focusing on the description of the concept and proof of the concept, to demonstrate the robustness of combined organo/metal catalysis in the creation of efficient enantioselective transformations. In addition, elegant studies from other laboratories using chiral phosphoric acid/Au(I) for the establishment of asymmetric cascade reactions involving the carbon-carbon triple bond functionality and typical combined organo/metal catalytic systems, very recently disclosed, will also be highlighted.
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Lumbo-femoral angle: a novel sagittal parameter related to quality of life in patients with adult scoliosis.
Eur Spine J
PUBLISHED: 06-08-2014
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PT and PI-LL sometimes offer limited utility in daily practice when evaluating QOL, especially in outpatient clinics with limited time and equipment facility. This study proposes a novel spino-pelvic parameter, lumbo-femoral angle (LFA). The purpose of this study is to analyze the correlation between LFA and HRQOL in adult scoliosis patients.
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The draft genome of the large yellow croaker reveals well-developed innate immunity.
Nat Commun
PUBLISHED: 06-02-2014
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The large yellow croaker, Larimichthys crocea, is one of the most economically important marine fish species endemic to China. Its wild stocks have severely suffered from overfishing, and the aquacultured species are vulnerable to various marine pathogens. Here we report the creation of a draft genome of a wild large yellow croaker using a whole-genome sequencing strategy. We estimate the genome size to be 728?Mb with 19,362 protein-coding genes. Phylogenetic analysis shows that the stickleback is most closely related to the large yellow croaker. Rapidly evolving genes under positive selection are significantly enriched in pathways related to innate immunity. We also confirm the existence of several genes and identify the expansion of gene families that are important for innate immunity. Our results may reflect a well-developed innate immune system in the large yellow croaker, which could aid in the development of wild resource preservation and mariculture strategies.
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Infection of Porcine Circovirus 2 (PCV2) in Intestinal Porcine Epithelial Cell Line (IPEC-J2) and Interaction between PCV2 and IPEC-J2 Microfilaments.
Virol. J.
PUBLISHED: 05-28-2014
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BackgroundPorcine circovirus-associated disease (PCVAD) is caused by a small pathogenic DNA virus, Porcine circovirus type 2 (PCV2), and is responsible for severe economic losses. PCV2-associated enteritis appears to be a distinct clinical manifestation of PCV2. Most studies of swine enteritis have been performed in animal infection models, but none have been conducted in vitro using cell lines of porcine intestinal origin. An in vitro system would be particularly useful for investigating microfilaments, which are likely to be involved in every stage of the viral lifecycle.MethodsWe confirmed that PCV2 infects the intestinal porcine epithelial cell line IPEC-J2 by means of indirect immunofluorescence, transmission electron microscopy, flow cytometry and qRT-PCR. PCV2 influence on microfilaments in IPEC-J2 cells was detected by fluorescence microscopy and flow cytometry. We used Cytochalasin D or Cucurbitacin E to reorganize microfilaments, and observed changes in PCV2 invasion, replication and release in IPEC-J2 cells by qRT-PCR.ResultsPCV2 infection changes the ultrastructure of IPEC-J2 cells. PCV2 copy number in IPEC-J2 cells shows a rising trend as infection proceeds. Microfilaments are polymerized at 1 h p.i., but densely packed actin stress fibres are disrupted and total F-actin increases at 24, 48 and 72 h p.i. After Cytochalasin D treatment, invasion of PCV2 is suppressed, while invasion is facilitated by Cucurbitacin E. The microfilament drugs have opposite effects on viral release.ConclusionPCV2 infects and proliferates in IPEC-J2 cells, demonstrating that IPEC-J2 cells can serve as a cell intestinal infection model for PCV2 pathogenesis. Furthermore, PCV2 rearranges IPEC-J2 microfilaments and increases the quantity of F-actin. Actin polymerization may facilitate the invasion of PCV2 in IPEC-J2 cells and the dissolution of cortical actin may promote PCV2 egress.
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Clinical Implementation of Intensity Modulated Proton Therapy for Thoracic Malignancies.
Int. J. Radiat. Oncol. Biol. Phys.
PUBLISHED: 05-01-2014
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Intensity modulated proton therapy (IMPT) can improve dose conformality and better spare normal tissue over passive scattering techniques, but range uncertainties complicate its use, particularly for moving targets. We report our early experience with IMPT for thoracic malignancies in terms of motion analysis and management, plan optimization and robustness, and quality assurance.
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Evaluation of the systematic error in using 3D dose calculation in scanning beam proton therapy for lung cancer.
J Appl Clin Med Phys
PUBLISHED: 04-28-2014
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The objective of this study was to evaluate and understand the systematic error between the planned three-dimensional (3D) dose and the delivered dose to patient in scanning beam proton therapy for lung tumors. Single-field and multifield optimized scanning beam proton therapy plans were generated for ten patients with stage II-III lung cancer with a mix of tumor motion and size. 3D doses in CT datasets for different respiratory phases and the time-weighted average CT, as well as the four-dimensional (4D) doses were computed for both plans. The 3D and 4D dose differences for the targets and different organs at risk were compared using dose-volume histogram (DVH) and voxel-based techniques, and correlated with the extent of tumor motion. The gross tumor volume (GTV) dose was maintained in all 3D and 4D doses, using the internal GTV override technique. The DVH and voxel-based techniques are highly correlated. The mean dose error and the standard deviation of dose error for all target volumes were both less than 1.5% for all but one patient. However, the point dose difference between the 3D and 4D doses was up to 6% for the GTV and greater than 10% for the clinical and planning target volumes. Changes in the 4D and 3D doses were not correlated with tumor motion. The planning technique (single-field or multifield optimized) did not affect the observed systematic error. In conclusion, the dose error in 3D dose calculation varies from patient to patient and does not correlate with lung tumor motion. Therefore, patient-specific evaluation of the 4D dose is important for scanning beam proton therapy for lung tumors.
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[Natural history of scoliosis after posterior fossa decompression in patients with Chiari malformation/syringomyelia].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 04-12-2014
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To explore the natural history of scoliosis after posterior fossa decompression (PFD) in patients with Chiari malformation/syringomyelia and examine the risk factors associated with curve progression.
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Asymmetric synthesis of heteroaryl atropisomers via a gold-catalyzed cycloisomerization-amination cascade reaction.
Chem. Commun. (Camb.)
PUBLISHED: 04-09-2014
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The chiral gold(i) complex enables enantioselective cycloisomerization-amination of 2-(alkynyl)phenyl boronic acids and diazenes in high yields. A wide scope of substrates bearing various functional groups was tolerated to generate structurally different hydrazide derivatives as a new type of atropisomer.
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New reactions of terminal hydrides on a diiron dithiolate.
J. Am. Chem. Soc.
PUBLISHED: 04-08-2014
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Mechanisms for biological and bioinspired dihydrogen activation and production often invoke the intermediacy of diiron dithiolato dihydrides. The first example of such a Fe2(SR)2H2 species is provided by the complex [(term-H)(?-H)Fe2(pdt)(CO)(dppv)2] ([H1H](0)). Spectroscopic and computational studies indicate that [H1H](0) contains both a bridging hydride and a terminal hydride, which, notably, occupies a basal site. The synthesis begins with [(?-H)Fe2(pdt)(CO)2(dppv)2](+) ([H1(CO)](+)), which undergoes substitution to afford [(?-H)Fe2(pdt)(CO)(NCMe)(dppv)2](+) ([H1(NCMe)](+)). Upon treatment of [H1(NCMe)](+) with borohydride salts, the MeCN ligand is displaced to afford [H1H](0). DNMR (EXSY, SST) experiments on this complex show that the terminal and bridging hydride ligands interchange intramolecularly at a rate of 1 s(-1) at -40 °C. The compound reacts with D2 to afford [D1D](0), but not mixed isotopomers such as [H1D](0). The dihydride undergoes oxidation with Fc(+) under CO to give [1(CO)](+) and H2. Protonation in MeCN solution gives [H1(NCMe)](+) and H2. Carbonylation converts [H1H](0) into [1(CO)](0).
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Sacrum pubic incidence and sacrum pubic posterior angle: two morphologic radiological parameters in assessing pelvic sagittal alignment in human adults.
Eur Spine J
PUBLISHED: 03-29-2014
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The morphology and position of pelvis are critical in regulating the biomechanical organization of spine-pelvis-leg in the sagittal plane. Several radiological parameters have been developed to present the sagittal morphology of the pelvis such as pelvic incidence (PI) and Jackson's angle (PRS1). In addition, the femoral sacral posterior angle (FSPA) was developed for patients with a dome-shaped deformity in the upper plate of the sacrum. The identification of hip axis, which was represented by the line connecting the centers of femoral heads in normal subjects, was important for these parameters measurement. However, in subjects with fused hip joint or deformed femoral heads, the accurate localization of hip axis become imprecise. Herein, the upper edge of the pubic symphysis, which is easy to identify on the lateral X-ray film, was selected as an alternative landmark of the hip axis, and two morphologic parameters, the sacrum pubic incidence (SPI) and sacrum pubic posterior angle (SPPA), were proposed accordingly. The present study aimed to understand the reliability of these two parameters and their value in predicting PI, PRS1 and FSPA.
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A novel mutation in COL2A1 leading to spondyloepiphyseal dysplasia congenita in a three-generation family.
Eur Spine J
PUBLISHED: 03-28-2014
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To investigate the genotype of COL2A1 in a three-generation spondyloepiphyseal dysplasia congenita (SEDC) family.
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Intensity Modulated Proton Therapy for Craniospinal Irradiation: Organ-at-Risk Exposure and a Low-Gradient Junctioning Technique.
Int. J. Radiat. Oncol. Biol. Phys.
PUBLISHED: 03-15-2014
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To compare field junction robustness and sparing of organs at risk (OARs) during craniospinal irradiation (CSI) using intensity modulated proton therapy (IMPT) to conventional passively scattered proton therapy (PSPT).
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Multifield optimization intensity modulated proton therapy for head and neck tumors: a translation to practice.
Int. J. Radiat. Oncol. Biol. Phys.
PUBLISHED: 03-06-2014
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We report the first clinical experience and toxicity of multifield optimization (MFO) intensity modulated proton therapy (IMPT) for patients with head and neck tumors.
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Brace treatment versus observation alone for scoliosis associated with Chiari I malformation following posterior fossa decompression: a cohort study of 54 patients.
Eur Spine J
PUBLISHED: 02-24-2014
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To be deemed effective in preventing curve progression, brace treatment should show alteration of the expected natural history. Most of the reported studies on the effect of bracing on the evolution of Chiari malformation-associated scoliosis (CMS) following posterior fossa decompression (PFD) were small series with inconclusive results. The goal of this study was to investigate whether post-PFD brace treatment for CMS produces better outcomes than observation alone.
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Spot scanning proton therapy for malignancies of the base of skull: treatment planning, acute toxicities, and preliminary clinical outcomes.
Int. J. Radiat. Oncol. Biol. Phys.
PUBLISHED: 02-20-2014
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To describe treatment planning techniques and early clinical outcomes in patients treated with spot scanning proton therapy for chordoma or chondrosarcoma of the skull base.
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Identification and comparative analysis of the Pseudosciaena crocea microRNA transcriptome response to poly(I:C) infection using a deep sequencing approach.
Fish Shellfish Immunol.
PUBLISHED: 02-20-2014
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Two sRNA libraries with or without poly(I:C) infection of large yellow croaker Pseudosciaena crocea were constructed and sequenced using the high-throughput Illumina/Solexa deep sequencing technology. The high-throughput sequencing pipeline yielded 163,79,272 and 217,07,070 raw reads corresponding to 132,27,594 and 206,86,409 clean reads for the normal and infected libraries, respectively. Bioinfromatic analysis identified 534 miRNAs, of which, 158 miRNAs were known in miRBase 20.0 and the remaining 376 were not found homology to any known metazoan miRNAs, suggesting a possible species-specificity. We analyzed the significance of differently expressed miRNAs between two libraries using pairwise comparison. There was significant differential expression of 112 miRNAs (p < 0.001) between two libraries. Thereinto, a number of known miRNAs were identified immune-related. Real-time quantitative PCR experiments (RT-qPCR) were preformed for 6 miRNAs of the two samples, and agreement was found between the sequencing and RT-qPCR data. To our knowledge, this is the first comprehensive study of miRNAs in P. crocea and of expression analysis of P. crocea miRNAs in response to poly(I:C) infection, and many miRNAs were differentially regulated under normal and infection conditions. These findings deepened our understanding of the role of miRNAs in the intricate host's immune system, and should be useful to develop new control strategies for host immune defense against various foreign infection in P. crocea.
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The relationship between moral judgment and cooperation in children with high-functioning autism.
Sci Rep
PUBLISHED: 02-20-2014
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This study investigated moral judgment in children with high-functioning autism and their cooperation in prisoner's dilemma game with partners of different moralities. Thirty-eight 6- to 12-year-old high-functioning autistic (HFA) children and 31 typically developing (TD) children were recruited. Children were asked to judge story protagonists' morality. After making this moral judgment correctly, they were asked to play with the morally nice and the morally naughty child in a repeated prisoner's dilemma game. Results showed that both HFA and TD children made correct moral judgments, and that HFA children might even have more rigid criteria for what constitutes morally naughty acts. HFA children's cooperation did not differ depending on the morality of the interaction partner, while TD children showed higher cooperation when interacting with the morally nice than the morally naughty child did. Thus, partner's morality did influence TD children's but not HFA children's subsequent cooperation.
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Evaluation and mitigation of the interplay effects of intensity modulated proton therapy for lung cancer in a clinical setting.
Pract Radiat Oncol
PUBLISHED: 02-19-2014
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The primary aim of this study was to evaluate the impact of the interplay effects of intensity modulated proton therapy (IMPT) plans for lung cancer in the clinical setting. The secondary aim was to explore the technique of isolayered rescanning to mitigate these interplay effects.
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Asymmetric organocatalytic direct C(sp²)-H/C(sp³)-H oxidative cross-coupling by chiral iodine reagents.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 02-19-2014
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An asymmetric organocatalytic direct C-H/C-H oxidative coupling reaction of N(1),N(3)-diphenylmalonamides has been well established by using chiral organoiodine compounds as catalysts, wherein four C-H bonds were stereoselectively functionalized to give structurally diverse spirooxindoles with high levels of enantioselectivity. More importantly, the findings indicated that chiral hypervalent organoiodine reagents can serve as alternative catalysts for the creation of enantioselective functionalization of inactive C-H bonds.
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Conservative treatment for osteoid osteoma of the odontoid process of the axis: a case report.
World J Surg Oncol
PUBLISHED: 02-15-2014
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Osteoid osteoma is a primary benign bone lesion, which constitutes about 10% of all primary benign bone tumors and 3% of all primary bone tumors. The spine is involved in 10% of the cases, and the lumbar spine is the most commonly affected whereas the tumor is rarely seen in the cervical spine. With regard to the osteoid osteoma being located at the odontoid process of the axis, limited cases have been reported in the literature.
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Inter- and intraobserver reliability assessment of the axial trunk rotation: manual versus smartphone-aided measurement tools.
BMC Musculoskelet Disord
PUBLISHED: 02-14-2014
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Scoliogauge, has been developed for the measurement of ATR on iPhone smartphones. This study was to evaluate the reliability for the smartphone-aided ATR measurement method and to compare its reliability with that of the manual method.
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On the interplay effects with proton scanning beams in stage III lung cancer.
Med Phys
PUBLISHED: 02-11-2014
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To assess the dosimetric impact of interplay between spot-scanning proton beam and respiratory motion in intensity-modulated proton therapy (IMPT) for stage III lung cancer.
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Sagittal spinopelvic alignment in adolescents associated with Scheuermann's kyphosis: a comparison with normal population.
Eur Spine J
PUBLISHED: 01-20-2014
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Spinopelvic alignment is increasingly considered as a main factor in the energy-efficient posture of the individual in normal and pathological status. However, the spinopelvic characteristics in Scheuermann's kyphosis (SK) are poorly defined in the literature. The purpose of this study was to determine whether differences of the spinopelvic parameters exist between adolescents with SK and age-matched normal controls.
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NMR structure of the S-linked glycopeptide sublancin 168.
ACS Chem. Biol.
PUBLISHED: 01-17-2014
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Sublancin 168 is a member of a small group of glycosylated antimicrobial peptides known as glycocins. The solution structure of sublancin 168, a 37-amino-acid peptide produced by Bacillus subtilis 168, has been solved by nuclear magnetic resonance (NMR) spectroscopy. Sublancin comprises two ?-helices and a well-defined interhelical loop. The two helices span residues 6-16 and 26-35, and the loop region encompasses residues 17-25. The 9-amino-acid loop region contains a ?-S-linked glucose moiety attached to Cys22. Hydrophobic interactions as well as hydrogen bonding are responsible for the well-structured loop region. The three-dimensional structure provides an explanation for the previously reported extraordinary high stability of sublancin 168.
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Dosimetric benefits of robust treatment planning for intensity modulated proton therapy for base-of-skull cancers.
Pract Radiat Oncol
PUBLISHED: 01-14-2014
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The clinical advantage of intensity modulated proton therapy (IMPT) may be diminished by range and patient setup uncertainties. We evaluated the effectiveness of robust optimization that incorporates uncertainties into the treatment planning optimization algorithm for treatment of base of skull cancers.
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An organocatalytic asymmetric allylic alkylation allows enantioselective total synthesis of hydroxymetasequirin-A and metasequirin-B tetramethyl ether diacetates.
Org. Lett.
PUBLISHED: 01-14-2014
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The first highly stereoselective organocatalytic intermolecular allylic alkylation of allylic alcohols with 1,3-dicarbonyls has been developed to allow the first enantioselective total synthesis of hydroxymetasequirin-A and metasequirin-B tetramethyl ether diacetates.
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Lack of association between suppressor of cytokine signaling-3 gene polymorphism and susceptibility and curve severity of adolescent idiopathic scoliosis.
Eur Spine J
PUBLISHED: 01-02-2014
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To explore whether the suppressor of cytokine signaling-3 (SOCS3) gene polymorphisms are associated with the susceptibility and abnormal growth pattern of adolescent idiopathic scoliosis (AIS).
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Myocardial Injury after Surgery Is a Risk Factor for Weaning Failure from Mechanical Ventilation in Critical Patients Undergoing Major Abdominal Surgery.
PLoS ONE
PUBLISHED: 01-01-2014
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Myocardial injury after noncardiac surgery (MINS) is a newly proposed concept that is common among adults undergoing noncardiac surgery and associated with substantial mortality. We analyzed whether MINS was a risk factor for weaning failure in critical patients who underwent major abdominal surgery.
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Picture norms for Chinese preschool children: name agreement, familiarity, and visual complexity.
PLoS ONE
PUBLISHED: 01-01-2014
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Pictorial stimuli standardized for Chinese children are still absent although it is needed in order to test the development of children's cognitive functions. This study presents normative measures for Snodgrass and Vanderwart pictures, viewed by 4- and 6-year old Chinese children. Name agreement, familiarity, and visual complexity were obtained for each age group. The data indicate substantial differences between young and older children in name agreement based on expected name, familiarity and visual complexity. The correlation pattern of the variables collected in the present study were consistent with children's norms in other languages and norms of Chinese adults, while there are cross-age and cross-culture differences in specific variables. The obtained measures represent a useful tool for further research on Chinese children's pictorial processing and constitute the first picture normative study for children in this language.
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Cloning and functional analysis of goat glucose transporter 4.
Mol. Biol. Rep.
PUBLISHED: 01-01-2014
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Glucose transporter (GLUT) 4 is a major mediator of blood glucose levels and a key regulator of whole-body glucose homeostasis. This study aimed at evaluating the function of goat GLUT4 on glucose absorption and the effect of GLUT4 on lactose synthesis in goat mammary gland epithelial (GMGE) cells.
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Patient-specific quantification of respiratory motion-induced dose uncertainty for step-and-shoot IMRT of lung cancer.
Med Phys
PUBLISHED: 12-11-2013
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Purpose: The objective of this study was to quantify respiratory motion-induced dose uncertainty at the planning stage for step-and-shoot intensity-modulated radiation therapy (IMRT) using an analytical technique.Methods: Ten patients with stage II?III lung cancer who had undergone a planning four-dimensional (4D) computed tomographic scan and step-and-shoot IMRT planning were selected with a mix of motion and tumor size for this retrospective study. A step-and-shoot IMRT plan was generated for each patient. The maximum and minimum doses with respiratory motion were calculated for each plan, and the mean deviation from the 4D dose was calculated, taking delivery time, fractionation, and patient breathing cycle into consideration.Results: For all patients evaluated in this study, the mean deviation from the 4D dose in the planning target volume (PTV) was <2.5%, with a standard deviation <1.2%, and maximum point dose variation from the 4D dose was <6.2% in the PTV assuming delivery dose rate of 200 MU?min and patient breathing cycle of 8 s. The motion-induced dose uncertainty is a function of motion, fractionation, MU (plan modulation), dose rate, and patient breathing cycle.Conclusions: Respiratory motion-induced dose uncertainty varies from patient to patient. Therefore, it is important to evaluate the dose uncertainty on a patient-specific basis, which could be useful for plan evaluation and treatment strategy determination for selected patients.
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Improving spot-scanning proton therapy patient specific quality assurance with HPlusQA, a second-check dose calculation engine.
Med Phys
PUBLISHED: 12-11-2013
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Purpose: The purpose of this study was to validate the use of HPlusQA, spot-scanning proton therapy (SSPT) dose calculation software developed at The University of Texas MD Anderson Cancer Center, as second-check dose calculation software for patient-specific quality assurance (PSQA). The authors also showed how HPlusQA can be used within the current PSQA framework.Methods: The authors compared the dose calculations of HPlusQA and the Eclipse treatment planning system with 106 planar dose measurements made as part of PSQA. To determine the relative performance and the degree of correlation between HPlusQA and Eclipse, the authors compared calculated with measured point doses. Then, to determine how well HPlusQA can predict when the comparisons between Eclipse calculations and the measured dose will exceed tolerance levels, the authors compared gamma index scores for HPlusQA versus Eclipse with those of measured doses versus Eclipse. The authors introduce the ??? transformation as a way to more easily compare gamma scores.Results: The authors compared measured and calculated dose planes using the relative depth, z?R × 100%, where z is the depth of the measurement and R is the proton beam range. For relative depths than less than 80%, both Eclipse and HPlusQA calculations were within 2 cGy of dose measurements on average. When the relative depth was greater than 80%, the agreement between the calculations and measurements fell to 4 cGy. For relative depths less than 10%, the Eclipse and HPlusQA dose discrepancies showed a negative correlation, -0.21. Otherwise, the correlation between the dose discrepancies was positive and as large as 0.6. For the dose planes in this study, HPlusQA correctly predicted when Eclipse had and had not calculated the dose to within tolerance 92% and 79% of the time, respectively. In 4 of 106 cases, HPlusQA failed to predict when the comparison between measurement and Eclipses calculation had exceeded the tolerance levels of 3% for dose and 3 mm for distance-to-agreement.Conclusions: The authors found HPlusQA to be reasonably effective (79% ± 10%) in determining when the comparison between measured dose planes and the dose planes calculated by the Eclipse treatment planning system had exceeded the acceptable tolerance levels. When used as described in this study, HPlusQA can reduce the need for patient specific quality assurance measurements by 64%. The authors believe that the use of HPlusQA as a dose calculation second check can increase the efficiency and effectiveness of the QA process.
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Catalytic cascade hydroalkoxylation/isomerization/ [4 + 2] cycloaddition using enyne alcohols as latent dienes or dienophiles.
Org. Biomol. Chem.
PUBLISHED: 11-01-2013
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Enyne alcohols can react as precursors of either dienes or dienophiles with different substrates after hydroxylation and isomerization by gold catalysis. As such, oxa-bridged tricyclo[5.2.2.02,6]-undec-8-ene-3,5-dione derivatives have been obtained by the Diels–Alder reaction and tetrahydro-1H-furo[3,4-c]pyran derivatives could be accessed by the hetero-Diels–Alder cycloaddition.
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Comparison of proton therapy techniques for treatment of the whole brain as a component of craniospinal radiation.
Radiat Oncol
PUBLISHED: 09-09-2013
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For treatment of the entire cranium using passive scattering proton therapy (PSPT) compensators are often employed in order to reduce lens and cochlear exposure. We sought to assess the advantages and consequences of utilizing compensators for the treatment of the whole brain as a component of craniospinal radiation (CSI) with PSPT. Moreover, we evaluated the potential benefits of spot scanning beam delivery in comparison to PSPT.
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Quality assurance of proton beams using a multilayer ionization chamber system.
Med Phys
PUBLISHED: 09-07-2013
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The measurement of percentage depth-dose (PDD) distributions for the quality assurance of clinical proton beams is most commonly performed with a computerized water tank dosimetry system with ionization chamber, commonly referred to as water tank. Although the accuracy and reproducibility of this method is well established, it can be time-consuming if a large number of measurements are required. In this work the authors evaluate the linearity, reproducibility, sensitivity to field size, accuracy, and time-savings of another system: the Zebra, a multilayer ionization chamber system.
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Preliminary evaluation of multifield and single-field optimization for the treatment planning of spot-scanning proton therapy of head and neck cancer.
Med Phys
PUBLISHED: 08-10-2013
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Spot-scanning proton therapy (SSPT) using multifield optimization (MFO) can generate highly conformal dose distributions, but it is more sensitive to setup and range uncertainties than SSPT using single-field optimization (SFO). The authors compared the two optimization methods for the treatment of head and neck cancer with bilateral targets and determined the superior method on the basis of both the plan quality and the plan robustness in the face of setup and range uncertainties.
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Rhodium/chiral urea relay catalysis enables an enantioselective semipinacol rearrangement/Michael addition cascade.
Org. Lett.
PUBLISHED: 07-25-2013
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The combined use of rhodium and cinchona-based squaramide has first been introduced for asymmetric relay catalysis, enabling a highly enantioselective semipinacol rearrangement/Michael addition cascade.
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Multilayered molecular profiling supported the monoclonal origin of metastatic renal cell carcinoma.
Int. J. Cancer
PUBLISHED: 07-10-2013
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Primary renal cell carcinomas (pRCCs) have a high degree of intratumoral heterogeneity and are composed of multiple distinct subclones. However, it remains largely unknown that whether metastatic renal cell carcinomas (mRCCs) also have startling intratumoral heterogeneity or whether development of mRCCs is due to early dissemination or late diagnosis. To decipher the evolution of mRCC, we analyzed the multilayered molecular profiles of pRCC, local invasion of the vena cava (IVC), and distant metastasis to the brain (MB) from the same patient using whole-genome sequencing, whole-exome sequencing, DNA methylome profiling, and transcriptome sequencing. We found that mRCC had a lower degree of heterogeneity than pRCC and was likely to result from recent clonal expansion of a rare, advantageous subclone. Consequently, some key pathways that are targeted by clinically available drugs showed distinct expression patterns between pRCC and mRCC. From the genetic distances between different tumor subclones, we estimated that the progeny subclone giving rise to distant metastasis took over half a decade to acquire the full potential of metastasis since the birth of the subclone that evolved into IVC. Our evidence supported that mRCC was monoclonal and distant metastasis occurred late during renal cancer progression. Thus, there was a broad window for early detection of circulating tumor cells and future targeted treatments for patients with mRCCs should rely on the molecular profiles of metastases.
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Incorporating deliverable monitor unit constraints into spot intensity optimization in intensity-modulated proton therapy treatment planning.
Phys Med Biol
PUBLISHED: 07-09-2013
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The purpose of this study is to investigate the feasibility and impact of incorporating deliverable monitor unit (MU) constraints into spot intensity optimization (SIO) in intensity-modulated proton therapy (IMPT) treatment planning. The current treatment planning system (TPS) for IMPT disregards deliverable MU constraints in the SIO routine. It performs a post-processing procedure on an optimized plan to enforce deliverable MU values that are required by the spot scanning proton delivery system. This procedure can create a significant dose distribution deviation between the optimized and post-processed deliverable plans, especially when small spot spacings are used. In this study, we introduce a two-stage linear programming approach to optimize spot intensities and constrain deliverable MU values simultaneously, i.e., a deliverable SIO (DSIO) model. Thus, the post-processing procedure is eliminated and the associated optimized plan deterioration can be avoided. Four prostate cancer cases at our institution were selected for study and two parallel opposed beam angles were planned for all cases. A quadratic programming based model without MU constraints, i.e., a conventional SIO (CSIO) model, was also implemented to emulate commercial TPS. Plans optimized by both the DSIO and CSIO models were evaluated for five different settings of spot spacing from 3 to 7 mm. For all spot spacings, the DSIO-optimized plans yielded better uniformity for the target dose coverage and critical structure sparing than did the CSIO-optimized plans. With reduced spot spacings, more significant improvements in target dose uniformity and critical structure sparing were observed in the DSIO than in the CSIO-optimized plans. Additionally, better sparing of the rectum and bladder was achieved when reduced spacings were used for the DSIO-optimized plans. The proposed DSIO approach ensures the deliverability of optimized IMPT plans that take into account MU constraints. This eliminates the post-processing procedure required by the TPS as well as the resultant deteriorating effect on ultimate dose distributions. This approach therefore allows IMPT plans to adopt all possible spot spacings optimally. Moreover, dosimetric benefits can be achieved using smaller spot spacings.
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Comparison of somatosensory evoked potentials between adolescent idiopathic scoliosis and congenital scoliosis without neural axis abnormalities.
Spine J
PUBLISHED: 07-05-2013
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Abnormal somatosensory evoked potentials (SEPs) have been documented in patients with adolescent idiopathic scoliosis (AIS) with different cure severity. However, few studies investigated whether abnormal SEPs were the cause or effect of idiopathic scoliosis.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.