The Effectiveness of CT Metal Artifact Reduction Technique and Its Contribution to Radiological Evaluation in Lumbar Stabilization

Objective:Metal artifact reduction (MAR) systems, which have been patented by the firms and specific to them, have been developed to reduce the losses in the images, which are caused by artifacts, and to increase the diagnostic value of computed tomography (CT). The objective of this study is to determine the effectiveness of the MAR technique, which minimizes the image loss caused by metal artifacts in CTs taken for the lumbar spinal region where metallic implants are located, and its contributions to radiological evaluation.Method:Patients with spinal stabilization, whose CT imaging records of both standard and smartMAR (SMAR) reconstruction were performed between June 2020 and March 2021 and could be accessed, were evaluated. Critical anatomical structures were defined as: spinal canal (SC), neural foramen (NF), and prevertebral-paravertebral area (P-PA). The image quality of critical anatomical structures were evaluated using a 5-point image quality scale for soft tissue (400/35 HU) and bone window settings (2.500/480 HU) on standard and SMAR reconstructed CT images. In addition, the size of the flame artifact was measured and recorded in millimeters in standard and SMAR images.Results:Of the 24 patients with lumbar spinal stabilization who met the inclusion criteria, 8 were male, and 16 were female (66%). The age range was determined to be between 26 and 82 years (mean=60). The stabilization of all patients was in the form of posterior transpedicular screw and rod fixation. The radiation dose distribution ranged between 3.23 and 14.1 millisieverts (mSv) (mean=8.95 mSv). The worst visualization score was obtained on SC imaging, which was evaluated in the soft tissue window. In bone window evaluations of these structures, the visualization scores (median) in standard and SMAR imaging’s were found to be 3 and 4 (Z=-3.926, p<0.001) for SC, 4 and 5 for NF (Z=-3.666, p<0.001), and 4 and 5 (Z=-4.203, p<0.0001) for P-PA, respectively. These differences were also significant. Bone cortex visualization score (median), measured on bone window images, were determined to be 4 (minimum:2, maximum:5) and 5 (minimum:4, maximum:5) (Z=-4.028, p<0,0001) in standard and SMAR imagings, respectively. As an objective criterion, the flame artifact length, which was evaluated only in bone window images, was 26 mm on average (standard deviation ±9.78) (minimum:8, maximum:54 mm) in standard imaging, whereas it decreased to 3.66 mm (standard deviation ±2.54) (minimum:0, maximum:7 mm) in reconstructions via SMAR.Conclusion:The MAR technique significantly reduces the artifacts occurring with standard techniques in adjacent tissues applied for medical treatment purposes and allows a clearer evaluation of this region by the radiologist. The use of this technique enhances the quality of CT images and the diagnostic value of radiological examination. However, there is a need for the development of MAR software for optimal imaging

In silico detection of Cucurbitacin-E on antioxidant enzymes of model organism Galleria mellonella L. (Lepidoptera: Pyralidae) and variation of antioxidant enzyme activities and lipid peroxidation in treated larvae

Background: In silico studies further provided predictive binding properties of selected ligands for inhibition of target protein. In the study, molecular binding poses of Cucurbitacin-E and antioxidant enzymes (glutathione-S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx) and acetylcholinesterase (AChE) of Galleria mellonella were determined in silico. Cucurbitacins are the most important components of Ecballium elaterium. The first cucurbitacin isolated from the plant was Cucurbitacin-E. In this study, the toxic effect of E. elaterium (L.) A. Rich. (Cucurbitaceae) fruit juice on G. mellonella (Lepidoptera: Pyralidae) larvae, which is known as a good model insect, was also detected, and its effect on antioxidant enzyme activities and lipid peroxidation was revealed. Results: The plant fruit juice was tested on the target larvae of G. mellonella with different doses for 24 h. After the application, mortality rate, LC50, LC90 and LC99 values, the malondialdehyde (MDA) level and the activity changes of antioxidant enzymes were determined. Mortality increased with the increasing concentration of fruit juice. Also, increasing doses of essential oil caused decreasing in SOD, CAT, GST GPx, GR and AChE activities and increasing in MDA levels. As a result of in silico studies, maximum binding energy was obtained from G. mellonella CAT enzyme with Cucurbitacin E as a ligand. Conclusions: This is the first study to demonstrate the in silico binding potential of Cucurbitacin E on G. mellonella enzymes. The results indicate that E. elaterium can be used against G. mellonella in a pest control program

Pregnancy-related sacral stress fractures: A single center experience of 23 cases

Purpose This study aims to find out the incidence, etiology, and risk factors, define clinical features, show the magnetic resonance imaging (MRI) and laboratory findings, and share the experience of treatment and clinical outcome of pregnancy-related sacral stress fractures (SSFs).Methods In total, 29,291 (15,008 of them vaginal and 14,283 of them cesarean section delivery) women gave birth in our hospital between January 2016 and December 2021. Twenty-three of them (0.078%) who had low back and pelvic pain were diagnosed with SSFs using pelvic MRI. Dual-energy X-ray absorptiometry (DEXA) was used to rule out underlying osteopenia and osteoporosis and determine the type of SSFs.Results The incidence of pregnancy-related SSFs was 0.078% (23/29,291patients). Six patients (26%) experienced pain during the last trimester of pregnancy, remaining seventeen (74%) patients had pain during the postpartum period. 73.91% of the patients were primigravida. Thirteen patients (56.52%) were classified as fatigue SSFs, eight (34.78%) were insufficiency SSFs, and only two (8.7%) were defined as a mixed type of SSFs. MRI imaging showed that nine patients (39.13%) had a left-sided fracture, seven patients (30.43%) had a right-sided fracture, and seven patients (30.43%) had bilateral fractures. Vitamin D deficiency (less than 20 ng/mL) was detected in seven patients (30.44%). One case had hypothyroidism in which thyroid stimulating hormone (TSH) was 5.41 mu IU/mL.Conclusion Pregnancy-related SSFs are uncommon but should be considered by clinicians in the differential diagnosis of low back and pelvic pain during pregnancy and the postpartum period. We determined that first pregnancy is a risk factor for SSFs. The current study also revealed that laboratory investigation of vitamin D deficiency and DEXA investigation, which may lead to osteoporosis or osteopenia, were crucial in the diagnosis. Furthermore, some SSFs should be reclassified as mixed fractures, fatigue, and insufficiency fractures

Ventriculocoronary Fistulas with Hypoplastic Left Heart in a Neonate: Imaging with Cardiac CT

Fistulous communications between the ventricular cavities and the coronary arterial tree can be found in the presence of hypoplasia of the left ventricle, especially when the ventricular septum is intact and mitral stenosis and aortic atresia subtype are present. The cardiac CT provides excellent anatomic information especially in the evaluation of extracardiac vessels and coronary arteries. In this case study, we report a newborn with ventriculocoronary fistulas (VCFs) with the hypoplastic left disease diagnosed with cardiac CT. Transthoracic echocardiography of a term baby showed hypoplastic left heart syndrome (HLHS) with mitral stenosis and aortic atresia. The patient immediately underwent a Sano variation of the Norwood procedure. On the postoperative second day, the clinical status of the patient deteriorated. A prospective electrocardiogram-gated axial technique was performed within a single heartbeat for the patient and large VCFs were detected and a second operation were performed to close the VCFs that failed. On the nineteenth day after the operation, the baby passed away. According to us, cardiac CT can also be performed free-breathing and without anesthesia in the neonatal period for the definition of complex cardiac anatomy with the lower radiation dose from the latest scanners, radiation risk of CT should be weighed against the anesthesia risk of cardiac MRI and intraoperative risk of conventional cardiac angiography. Pre-operative cardiac CT may increase surgical success

Esculentin2PLa, a frog skin antimicrobial peptide, causes necrotic cell death in breast cancer cell lines

Background: Antimicrobial peptides are molecules which play important roles in the natural immune system from insects to mammals. These peptides show significant differences in terms of amino acid sequence and secondary structure. The net charges of these peptides vary between +2 to +9 in neutral pH and their cationic characters based on the basic amino acids such as arginine and lysine. On the other hand, these peptides are short peptides composed of 5&minus;40 amino acids and 30% or more of these amino acids have hydrophobic character. Beside bacteria killing and immunomodulatory effects, these peptides have gained attention in recent years due to their anticancer activities. In this study we aimed to research the anticancer activity of Esculentin-2PLa on breast cancer cell lines, MCF-7 and MDA-MB 231. Esculentin-2PLa is a 37-mer peptide that is firstly defined in the skin secretion of Rana palustris and the net charge and hydrophobicity is +5 and 48%, respectively. Material and Methods: Estrogen receptor (ER) positive cell line, MCF-7 and ER(&minus;) cell line, MDA-MB 231 were used in this study. Antitumor activity was determined with cell proliferation assay and cell cytotoxicity assay after treatment with 0&ndash;200 mg/ml Esculentin-2PLa for 24 hours. The cell death mechanism was investigated by measuring activity of caspase-3 and counting stained the apoptotic and necrotic cells with acridine orange-ethidium bromide. The cell morphology after the peptide treatment was observed by scanning electron microscopy. In addition, possible electrostatic interactions between cell membranes and the peptide were researched by solid-phase heparan sulfate and chondroitin sulfate binding assay and by measuring the affinity of peptide to cancer cell membranes. Results: Esculentin-2PLa reduced cell viability in a dose dependent manner in the two cell lines and MDA-MB 231 cell line was more sensitive. Beside this, the peptide caused the release of lactate dehydrogenase (LDH) from the cells. In addition, necrotic cell death was detected in both cell lines by observing membrane pores with scanning electrone microscope and this finding was consistent with the increase in the number of cell nuclei stained with etidium bromide. Moreover, Esculentin-2PLa attached to heparan sulfate and chondroitin sulfate proteoglycans which are abundant on cancer cell membranes in a dose dependent manner. Furthermore, this peptide has a high affinity to cancer cell membranes via electrostatic interaction. Conclusions: Overall, these results suggest that Esculentin-2PLa induced cell death through membranolytic effects and its anticancer activity may arise from its cationic and hydrophobic characters which facilitate the interaction with cancer cell membranes. Our findings indicate that Esculentin-2PLa has the potential for development as anticancer agent. No conflict of interest