Cloning and expression of codon-optimized recombinant darbepoetin alfa in Leishmania tarentolae T7-TR

Darbepoetin alfa is an engineered and hyperglycosylated analog of recombinant human erythropoietin (EPO) which is used as a drug in treating anemia in patients with chronic kidney failure and cancer. This study desribes the secretory expression of a codon-optimized recombinant form of darbepoetin alfa in Leishmania tarentolae T7-TR. Synthetic codon-optimized gene was amplified by PCR and cloned into the pLEXSY-I-blecherry3 vector. The resultant expression vector, pLEXSYDarbo, was purified, digested, and electroporated into the L. tarentolae. Expression of recombinant darbepoetin alfa was evaluated by ELISA, reverse-transcription PCR (RT-PCR), Western blotting, and biological activity. After codon optimization, codon adaptation index (CAI) of the gene raised from 0.50 to 0.99 and its GC content changed from 56 to 58. Expression analysis confirmed the presence of a protein band at 40 kDa. Furthermore, reticulocyte experiment results revealed that the activity of expressed darbepoetin alfa was similar to that of its equivalent expressed in Chinese hamster ovary (CHO) cells. These data suggested that the codon optimization and expression in L. tarentolae host provided an efficient approach for high level expression of darbepoetin alfa. © 2015 Elsevier Ltd. All rights reserved

A simple way to distinguish bed clothing contamination in a whole body bone scan: a case report

Whole body bone scan with Technetium-99m MDP (methylene diphosphate) can detect bony lesions due to altered osteoblastic activity

Comparison of MRI findings with traditional criteria in diagnosis of Pendred syndrome

Pendred syndrome, defined as the constellation of goiter, sensori-neural hearing loss, and positive perchlorate discharge test, is the most frequent cause of congenital deafness. Newly introduced diagnostic approaches to the disease are rather expensive and complicated, therefore we evaluated the value of MRI as the sole, or adjunctive diagnostic approach, and compared it with the traditional ones. Presuming the classic triad as the gold standard, we compared MRI findings in six such defined patients with six cases having goiter, hearing loss, and normal perchlorate discharge test. Our results indicated that MRI was 83.6 sensitive and 66.7 specific in patients fulfilling all three criteria (complete), while in the 'partial' group the sensitivity and specificity were 66.7 and 100 respectively. In conclusion, MRI, although impressive as an adjunctive diagnostic tool, may not replace the holistic approach, and the latter may be more convenient, cheaper, and still more accurate. However in 'partial' cases with equivocal findings, and in relatives of the patients, MRI may be a valuable diagnostic adjunct. © 2007 British Society of Audiology, International Society of Audiology, and Nordic Audiological Society

Frequency and severity of myocardial perfusion abnormalities using Tc-99m MIBI SPECT in cardiac syndrome X

BACKGROUND: Cardiac syndrome X is defined by a typical angina pectoris with normal or near normal (stenosis <40%) coronary angiogram with or without electrocardiogram (ECG) change or atypical angina pectoris with normal or near normal coronary angiogram plus a positive none-invasive test (exercise tolerance test or myocardial perfusion scan) with or without ECG change. Studies with myocardial perfusion imaging on this syndrome have indicated some abnormal perfusion scan. We evaluated the role of myocardial perfusion imaging (MPI) and also the severity and extent of perfusion abnormality using Tc-99m MIBI Single Photon Emission Computed Tomography (SPECT) in these patients. METHODS: The study group consisted of 36 patients with cardiac syndrome X. The semiquantitative perfusion analysis was performed using exercise Tc-99m MIBI SPECT. The MPI results were analyzed by the number, location and severity of perfusion defects. RESULTS: Abnormal perfusion defects were detected in 13 (36.10%) cases, while the remaining 23 (63.90%) had normal cardiac imaging. Five of 13 (38.4%) abnormal studies showed multiple perfusion defects. The defects were localized in the apex in 3, apical segments in 4, midventricular segments in 12 and basal segments in 6 cases. Fourteen (56%) of all abnormal segments revealed mild, 7(28%) moderate and 4 (16%) severe reduction of tracer uptake. No fixed defects were identified. The vessel territories were approximately the same in all subjects. The Exercise treadmill test (ETT) was positive in 25(69%) and negative in 11(30%) patients. There was no consistent pattern as related to the extent of MPI defects or exercise test results. CONCLUSION: Our study suggests that multiple perfusion abnormalities with different levels of severity are common in cardiac syndrome X, with more than 30 % of these patients having at least one abnormal perfusion segment. Our findings suggest that in these patients microvascular angina is probably more common than is generally believed

Effects Of Treatment With Radioactive Iodine On Gonadal Functions In Patients With Differentiated Thyroid Cancer

Background: The purpose of this study was to evaluate the effect of treatment with radioactive iodine on the function of gonads in males and females with follicular and papillary thyroid carcinoma. Materials and Methods: Consenting patients in the reproductive age were grouped according to the cumulative dose of received radioiodine and followed for at least 12 months. For all men, serum levels of FSH, LH, and testosterone were measured; some (53 cases) were also studied by semen analysis. For women, tests for serum levels of LH, FSH, estrogen, and progesterone were performed. Results: Overall, 246 patients (159 females, 87 males) were studied. In 87.4% of men, there was an increase in serum FSH level after radioiodine therapy, in 20.7% of whom the level remained high during follow-up period. The average serum level of FSH after each course of treatment was significantly higher than the level before treatment (p&lt;0.01), and there was a meaningful correlation with the cumulative dose of received iodine (p&lt;0.001). Reduced number of sperms was shown in 35.8% of male patients, among whom 73.7% also showed reduced motility. In 36.8% of the patients with reduced sperm number (13.2% of the total), this finding was persistent during the follow-up period. Increased level of FSH was correlated with reduced sperm counts in all doses (p&lt;o.oo5). There was no significant correlation between serum levels of LH and testosterone with iodine treatment in males (p=0.47). In women, no significant correlation between gonadal-hypophyseal hormones and treatment with radioactive iodine was found, and there were no signs and symptoms of sexual dysfunction. Infertility was not noticed in any patient and no case of abortion was found. Conclusion: It seems that cells in spermatogonia lineage (in contrast to Leydig cells) are radiosensitive, with the sensitivity related to the cumulative dose of received radioactive iodine. But in the oogonia cell line, the radiosensitivity is insignificant

Quantification of PET and CT misalignment errors due to bulk motion in cardiac PET/CT imaging: Phantom and clinical and studies

Purpose: Non simultaneous acquisition between CT and PET module can introduce misalignment artefact in cardiac PET/CT imaging due to patient motion. We assessed the clinical impact of patient motion and the resulting mismatch between CT and corresponding CT-based attenuation corrected (CTAC) PET images on apparent myocardial uptake values in cardiac PET/CT imaging. Methods: The evaluation of patient motion was performed using clinical and experimental phantom studies acquired on the Biograph TP 64 PET/CT scanner. In order to simulate patient motion, CT images were manually shifted from 0 to 20 mm in steps of 5-mm in six different directions. The reconstructed PET images using shifted CT were compared with the original PET images. The assessment of PET images was performed through qualitative interpretation by an experienced nuclear medicine physician and through quantitative analysis using volume of interest based analysis. Moreover, Box and Whisker plots were calculated and bull's eye view analysis performed. PET images were also reoriented along the short, horizontal and vertical long axis views for a better qualitative interpretation. Results: A 20-mm shift in the right direction between attenuation and PET emission scans produced mean absolute percentage difference in uptake values in the lateroanterior (33.42±9.07) and lateroinferior (27.39±10.43) segments of the myocardium. Conclusion: Misalignment could introduce artifactual nonuniformities in apparent myocardial uptake value and the variations were more significant for the misalignment toward the right, feet and head directions, in such a way that even with a 5-mm shift in the CT image, errors in interpretation of PET images could occur. Furthermore, errors in PET uptake estimates were observed for movements as large as 10-mm in the left, posterior and anterior directions

SCINTIGRAPHIC SCREENING IN THE DETECTION OF RENAL SCARRING IN SIBLINGS OF CHILDREN WITH PRIMARY REFLUX

&quot;nThe correlation of vesicoureteral reflux (VUR), urinary tract infection (UTI) and renal scarring is well known. Several risk factors for renal parenchymal lesions have been reported previously. We determine the incidence of renal parenchymal damage and outcome in the siblings of children with primary VUR. A total of 96 siblings of patients with VUR, were evaluated with direct voiding cystography, 99m-technetium (Tc)-dimercaptosuccinic acid (DMSA) renal scintigraphy and renal ultrasonography (US). Of 96 siblings, 34 were found to have VUR, representing an incidence of 35.4%. The majority of siblings with abnormal DMSA scans were asymptomatic. Parenchymal abnormalities were determined by DMSA in 23 (69.6%) of the 33 siblings studied (37 of 46 refluxing renal units or 80.4% P &amp;lt;0.001). Of these, 10 (30.3%) were normal. Renal damage was mild, moderate and severe in 30.3%, 54.5%, and 15.2% of children, respectively. Renal US in 34 siblings with VUR was normal in 27 (79.4%) and abnormal in 7 (20.5%). Of the 33 siblings with VUR who had both renal cortical scintigraphy and renal US, DMSA and US findings were abnormal in 23 and 7 of the siblings, respectively. Parenchymal abnormalities on scintigraphy were associated with mild-to-moderate reflux in 51.5% and severe reflux in 72.7% renal units. This study confirms a significant overall incidence of renal parenchymal damage in 69.6% and VUR in 35.4% of siblings studied. Most importantly, the lack of symptoms within the siblings group can not be used as a reason to avoid screening process. DMSA scintigraphy of asymptomatic siblings appears to be beneficial in preventing renal injury

Neo-adjuvant chemoradiotherapy response prediction using MRI based ensemble learning method in rectal cancer patients

Objectives: The aim of this study was to investigate and validate the performance of individual and ensemble machine learning models (EMLMs) based on magnetic resonance imaging (MRI) to predict neo-adjuvant chemoradiation therapy (nCRT) response in rectal cancer patients. We also aimed to study the effect of Laplacian of Gaussian (LOG) filter on EMLMs predictive performance. Methods: 98 rectal cancer patients were divided into a training (n = 53) and a validation set (n = 45). All patients underwent MRI a week before nCRT. Several features from intensity, shape and texture feature sets were extracted from MR images. SVM, Bayesian network, neural network and KNN classifiers were used individually and together for response prediction. Predictive performance was evaluated using the area under the receiver operator characteristic (ROC) curve (AUC). Results: Patients' nCRT responses included 17 patients with Grade 0, 28 with Grade 1, 34 with Grade 2, and 19 with Grade 3 according to AJCC/CAP pathologic grading. In without preprocessing MR Image the best result was for Bayesian network classifier with AUC and accuracy of 75.2 and 80.9 respectively, which was confirmed in the validation set with an AUC and accuracy of 74 and 79 respectively. In EMLMs the best result was for 4 (SVM.NN.BN.KNN) classifier EMLM with AUC and accuracy of 97.8 and 92.8 in testing and 95 and 90 in validation set respectively. Conclusions: In conclusion, we observed that machine learning methods can used to predict nCRT response in patients with rectal cancer. Preprocessing LOG filters and EL models can improve the prediction process. © 2019 Associazione Italiana di Fisica Medic