scholarly journals Assessment of retinoblastoma RNA reflux after intravitreal injection of melphalan

2017 ◽  
Vol 102 (3) ◽  
pp. 415-418 ◽  
Author(s):  
Ursula Winter ◽  
Michael Nicolas ◽  
Mariana Sgroi ◽  
Claudia Sampor ◽  
Ana Torbidoni ◽  
...  
Keyword(s):  
Intravitreal Injection ◽  
Tumour Cell ◽  
Limit Of Detection ◽  
Local Treatment ◽  
Homeobox Gene ◽  
Simple Method ◽  
Retinoblastoma Cell ◽  
Filter Papers ◽  
Cell Dissemination ◽  
Vitreous Seeds

BackgroundIntravitreal injection of chemotherapy in retinoblastoma eyes with vitreous seeds may lead to a risk of extraocular tumour dissemination that has not been assessed so far.AimsTo develop a sensitive and clinically feasible technique to assess for potential retinoblastoma cell reflux after intravitreal injection of melphalan.MethodsFilter papers were cut in 6 mm diameter circles and sterilised before use. Eyes with retinoblastoma vitreous seeds (group D, International Classification) received weekly intravitreal melphalan injections (20 µg or 30 µg/dose) followed by cryotherapy as part of local treatment. Immediately after finishing the injection and cryotherapy, filter papers were placed on the injection site and on the cryoprobe tip to assess for the expression of the cone-rod homeobox gene (CRX) by real-time qPCR as a surrogate of retinoblastoma RNA. The assay was developed and validated to determine sensitivity, linearity, recovery, repeatability and reproducibility.ResultsThe assay for quantitation of CRX expression was linear in the range of 1 to 1000 cells. The lowest limit of detection was one retinoblastoma cell and allowed to recover 100% of the cell load in external supplementation. A total of 14 eyes received 22 cycles of intravitreal melphalan and were evaluated for potential extraocular tumour cell dissemination using the developed technique. None of the cycles were positive for CRX in samples from the scar or from the cryoprobe tip.ConclusionsA sensitive and simple method of tumour cell assessment has been developed that can be used in the clinics to assess for potential extraocular dissemination after intravitreal injections to assure its performance.

scholarly journals A Simple Method for Evaluating the Bioactive Phenolic Compounds’ Presence in Brazilian Craft Beers

Molecules ◽  
2021 ◽  
Vol 26 (16) ◽  
pp. 4716
Author(s):  
Marcelo Coelho Silva ◽  
Jeancarlo Pereira dos Anjos ◽  
Lilian Lefol Nani Guarieiro ◽  
Bruna A. Souza Machado
Keyword(s):  
Phenolic Compounds ◽  
Caffeic Acid ◽  
Good Accuracy ◽  
Limit Of Detection ◽  
Coumaric Acid ◽  
Simple Method ◽  
Craft Beer ◽  
Extraction Step ◽  
Satisfactory Precision ◽  
Craft Beers

There are a significant number of analytical methodologies employing different techniques to determine phenolic compounds in beverages. However, these methods employ long sample preparation processes and great time consumption. The aim of this paper was the development of a simple method for evaluating the phenolic compounds’ presence in Brazilian craft beers without a previous extraction step. Catechin, caffeic acid, epicatechin, p-coumaric acid, hydrated rutin, trans-ferulic acid, quercetin, kaempferol, and formononetin were analyzed in fifteen different craft beers. The method showed good linearity (R2 ≥ 0.9966). The limit of detection ranged from 0.08 to 0.83 mg L−1, and limits of quantification were between 0.27 and 2.78 mg L−1. The method showed a satisfactory precision (RSD ≤ 16.2%). A good accuracy was obtained by the proposed method for all phenolic compounds in craft beer (68.6% ˂ accuracy ˂ 112%). Catechin showed higher concentrations (up to 124.8 mg L−1) in the samples, followed by epicatechin (up to 51.1 mg L−1) and caffeic acid (up to 8.13 mg L−1). Rutin and formononetin were observed in all analyzed samples (0.52 mg L−1 to 2.40 mg L−1), and kaempferol was less present in the samples. The presence of plant origin products was determinant for the occurrence of the highest concentrations of phenolic compounds in Brazilian craft beers.

scholarly journals Evaluation of intravitreal topotecan dose levels, toxicity and efficacy for retinoblastoma vitreous seeds: a preclinical and clinical study

2021 ◽  
pp. bjophthalmol-2020-318529
Author(s):  
Carley M Bogan ◽  
Jessica V Kaczmarek ◽  
Janene M Pierce ◽  
Sheau-chiann Chen ◽  
Kelli L Boyd ◽  
...  
Keyword(s):  
Cohort Study ◽  
Clinical Study ◽  
Tumour Cell ◽  
Retrospective Cohort Study ◽  
Retrospective Cohort ◽  
Rabbit Model ◽  
Retinal Toxicity ◽  
Apoptosis Induction ◽  
Dose Levels ◽  
Vitreous Seeds

BackgroundCurrent melphalan-based intravitreal regimens for retinoblastoma (RB) vitreous seeds cause retinal toxicity. We assessed the efficacy and toxicity of topotecan monotherapy compared with melphalan in our rabbit model and patient cohort.MethodsRabbit experiments: empiric pharmacokinetics were determined following topotecan injection. For topotecan (15 μg or 30 µg), melphalan (12.5 µg) or saline, toxicity was evaluated by serial electroretinography (ERG) and histopathology, and efficacy against vitreous seed xenografts was measured by tumour cell reduction and apoptosis induction. Patients: retrospective cohort study of 235 patients receiving 990 intravitreal injections of topotecan or melphalan.ResultsIntravitreal topotecan 30 µg (equals 60 µg in humans) achieved the IC90 across the rabbit vitreous. Three weekly topotecan injections (either 15 µg or 30 µg) caused no retinal toxicity in rabbits, whereas melphalan 12.5 µg (equals 25 µg in humans) reduced ERG amplitudes 42%–79%. Intravitreal topotecan 15 µg was equally effective to melphalan to treat WERI-Rb1 cell xenografts in rabbits (96% reduction for topotecan vs saline (p=0.004), 88% reduction for melphalan vs saline (p=0.004), topotecan vs melphalan, p=0.15). In our clinical study, patients received 881 monotherapy injections (48 topotecan, 833 melphalan). Patients receiving 20 µg or 30 µg topotecan demonstrated no significant ERG reductions; melphalan caused ERG reductions of 7.6 μV for every injection of 25 µg (p=0.03) or 30 µg (p<0.001). Most patients treated with intravitreal topotecan also received intravitreal melphalan at some point during their treatment course. Among those eyes treated exclusively with topotecan monotherapy, all eyes were salvaged.ConclusionsTaken together, these experiments suggest that intravitreal topotecan monotherapy for the treatment of RB vitreous seeds is non-toxic and effective.

scholarly journals A simple method to estimate the in-house limit of detection for genetic mutations with low allele frequencies in whole-exome sequencing analysis by next-generation sequencing

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Takumi Miura ◽  
Satoshi Yasuda ◽  
Yoji Sato
Keyword(s):  
Next Generation Sequencing ◽  
Allele Frequency ◽  
Somatic Mutations ◽  
Limit Of Detection ◽  
Allele Frequencies ◽  
Genetic Mutations ◽  
Sequencing Data ◽  
Simple Method ◽  
Whole Exome ◽  
Generation Sequencing

Abstract Background Next-generation sequencing (NGS) has profoundly changed the approach to genetic/genomic research. Particularly, the clinical utility of NGS in detecting mutations associated with disease risk has contributed to the development of effective therapeutic strategies. Recently, comprehensive analysis of somatic genetic mutations by NGS has also been used as a new approach for controlling the quality of cell substrates for manufacturing biopharmaceuticals. However, the quality evaluation of cell substrates by NGS largely depends on the limit of detection (LOD) for rare somatic mutations. The purpose of this study was to develop a simple method for evaluating the ability of whole-exome sequencing (WES) by NGS to detect mutations with low allele frequency. To estimate the LOD of WES for low-frequency somatic mutations, we repeatedly and independently performed WES of a reference genomic DNA using the same NGS platform and assay design. LOD was defined as the allele frequency with a relative standard deviation (RSD) value of 30% and was estimated by a moving average curve of the relation between RSD and allele frequency. Results Allele frequencies of 20 mutations in the reference material that had been pre-validated by droplet digital PCR (ddPCR) were obtained from 5, 15, 30, or 40 G base pair (Gbp) sequencing data per run. There was a significant association between the allele frequencies measured by WES and those pre-validated by ddPCR, whose p-value decreased as the sequencing data size increased. By this method, the LOD of allele frequency in WES with the sequencing data of 15 Gbp or more was estimated to be between 5 and 10%. Conclusions For properly interpreting the WES data of somatic genetic mutations, it is necessary to have a cutoff threshold of low allele frequencies. The in-house LOD estimated by the simple method shown in this study provides a rationale for setting the cutoff.

Authors' reply: Tumour cell dissemination following endoscopic stent insertion (Br J Surg 2007; 94: 1151-1154)

2007 ◽  
Vol 95 (1) ◽  
pp. 128-128
Author(s):  
K. Maruthachalam ◽  
G. E. Lash ◽  
B. K. Shenton ◽  
A. F. Horgan
Keyword(s):  
Tumour Cell ◽  
Stent Insertion ◽  
Endoscopic Stent ◽  
Cell Dissemination ◽  
Tumour Cell Dissemination

scholarly journals Development and Validation of a Simple Method for Routine Analysis of Ractopamine Hydrochloride in Raw Material and Feed Additives by HPLC

2009 ◽  
Vol 92 (3) ◽  
pp. 757-764 ◽  
Author(s):  
Ellen Figueiredo Freire ◽  
Keyller Bastos Borges ◽  
Hélio Tanimoto ◽  
Raquel Tassara Nogueira ◽  
Lucimara Cristiane Toso Bertolini ◽  
...  
Keyword(s):  
Quality Control ◽  
Limit Of Detection ◽  
Feed Additives ◽  
Raw Material ◽  
Control Analysis ◽  
Limit Of Quantification ◽  
Simple Method ◽  
Relative Standard ◽  
Validation Parameters ◽  
Ractopamine Hydrochloride

Abstract A simple method was optimized and validated for determination of ractopamine hydrochloride (RAC) in raw material and feed additives by HPLC for use in quality control in veterinary industries. The best-optimized conditions were a C8 column (250 4.6 mm id, 5.0 m particle size) at room temperature with acetonitrile100 mM sodium acetate buffer (pH 5.0; 75 + 25, v/v) mobile phase at a flow rate of 1.0 mL/min and UV detection at 275 nm. With these conditions, the retention time of RAC was around 5.2 min, and standard curves were linear in the concentration range of 160240 g/mL (correlation coefficient 0.999). Validation parameters, such as selectivity, linearity, limit of detection (ranged from 1.60 to 2.05 g/mL), limit of quantification (ranged from 4.26 to 6.84 g/mL), precision (relative standard deviation 1.87), accuracy (ranged from 96.97 to 100.54), and robustness, gave results within acceptable ranges. Therefore, the developed method can be successfully applied for the routine quality control analysis of raw material and feed additives.

Intravitreal topotecan in the management of refractory and recurrent vitreous seeds in retinoblastoma

2017 ◽  
Vol 102 (4) ◽  
pp. 490-495 ◽  
Author(s):  
Raksha Rao ◽  
Santosh G Honavar ◽  
Vishal Sharma ◽  
Vijay Anand P Reddy
Keyword(s):  
Visual Acuity ◽  
Intravitreal Injection ◽  
Primary Treatment ◽  
Complete Regression ◽  
Intravenous Chemotherapy ◽  
Systemic Complications ◽  
Group D ◽  
Vitreous Seeds

Background/aimTo evaluate the efficacy of intravitreal topotecan for refractory or recurrent vitreous seeds in retinoblastoma.MethodsIntravitreal injection of topotecan hydrochloride (30 µg/0.15 mL) was provided every 3 weeks by the safety enhanced technique.ResultsThe study included 17 consecutive patients with retinoblastoma with refractory or recurrent vitreous seeds. Five eyes (29%) belonged to International Classification of Retinoblastoma group C and 12 eyes (71%) belonged to group D. Primary treatment included triple drug intravenous chemotherapy for a mean of 10 cycles (median, 9 cycles; range, 6–18 cycles). Fifteen patients (88%) had undergone 56 periocular carboplatin injections with a mean of 4 injections (median, 3 injections; range, 1–8 injections), concurrent with intravenous chemotherapy. A total of 53 intravitreal topotecan injections were performed in 17 eyes of 17 consecutive patients with refractory or recurrent vitreous seeds with a mean of 3 injections (median, 3 injections; range, 2–6 injections). Complete regression of vitreous seeds was achieved in 17 of 17 eyes (100%). At a mean follow-up of 23.8 months (median, 24 months; range, 15.1–34.1 months), one eye (6%) with a recurrent retinal tumour needed enucleation, and the rest of the 16 eyes (94%) maintained complete regression. Final visual acuity could be reliably assessed in all 16 eyes (100%), of whom 12 eyes (75%) had visual acuity ≥20/200. None of the patients developed ocular or systemic complications.ConclusionThree-weekly intravitreal topotecan appears effective and safe in controlling focal or diffuse refractory or recurrent vitreous seeds in retinoblastoma.

Early tumour cell dissemination in non-small cell lung cancer

1994 ◽  
Vol 30 ◽  
pp. S35
Author(s):  
K. Pantel ◽  
B. Passlick ◽  
J.R. Izbicki ◽  
M. Angstwurm ◽  
B. Kubuschok ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
Tumour Cell ◽  
Small Cell ◽  
Small Cell Lung ◽  
Cell Dissemination ◽  
Tumour Cell Dissemination

scholarly journals A simple method for the analysis of urinary sucralose for use in tests of intestinal permeability

2005 ◽  
Vol 42 (3) ◽  
pp. 224-226 ◽  
Author(s):  
A D G Anderson ◽  
P Poon ◽  
G M Greenway ◽  
J MacFie
Keyword(s):  
Refractive Index ◽  
Limit Of Detection ◽  
Internal Standard ◽  
Simple Method ◽  
Standard Curve ◽  
Additional Information ◽  
Accuracy And Precision ◽  
Analytical Recovery ◽  
Peak Areas ◽  
Syringe Filter

Background: Sucralose is a unique disaccharide probe which is stable in the colon and can be used to assess permeability over the whole gut. Additional information can be gained when sucralose is administered in combination with lactulose and a monosaccharide such as L-rhamnose in the form of a 'triple sugar test.' We describe a simple assay for urinary sucralose by HPLC with refractive index detection (HPLC-RI). Methods: Phenyl-β-D-glucopyranoside (internal standard) was added to 10 mL of urine, which was then passed through a 0.45 μm syringe filter. Elution was with 30% methanol (1 mL/min) on a reverse-phase C18 column. Detection was by refractive index, and integration based upon peak areas. Sixty standards of sucralose in human urine were analysed in order to quantify analytical variation. Results: The standard curve for urinary sucralose was linear from 25 to 500 mg/L ( r>0.99). The limit of detection was 11 mg/L. Analytical recovery of sucralose at concentrations of 25, 50 and 100 mg/L was 101.5% (CV 7.59%), 102.9% (CV 5.82%) and 105.0% (CV 4.26%), respectively Conclusions: The technique described represents a simple assay for urinary sucralose which performed with acceptable accuracy and precision and should facilitate the use of the triple sugar test in clinical research.

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