Role of Magnetic Resonance Imaging in Patients with Rectal Cancer

In a chapter about rectal cancer there is content about rectal anatomy in relation to magnet-resonanse imaging and TME- surgery (total mesorectal excision). Secondly there is content about imaging methods used in diagnosis and follow-up of rectal cancer. Very important topic is concerning the novel imaging strategies in surgical and radiotherapy planning in the era of individual oncologic approach to the patient. At last there is detailed desctiption and metaanalysis of imaging strategies concerning neoadjuvant and adjuvant radiotherapy and chemotherapy for rectal cancer patients. All imaging markers correspond to substantial oncologic parameters such as survival rates. The connecting bridge is magnet-resonance imaging

Examining The Effect Of The Online Radiological Consultation Platform StatDx

StatDx е онлайн платформа за бърза справка в полза на клиничните радиолози и образни диагностици. Състои се от редица свързани помежду си статии за диагнози и диференциални диагнози, позволяващи бързо и интуитивно търсене, сортиране и сравнение на нозологични единици и образни белези. Системата е снабдена с богат диапазон от изображения, включително схеми и образи от различните образни модалности, всички от които подробно анотирани. Тази система бе въведена за ползване в Клиниката по образна диагностика в УМБАЛ „Света Марина“ – Варна в началото на 2017 г. Над година след това бе проведено вътрешно анонимно проучване на индивидуалните мнения на ползващите я лекари – в това число 14 специалисти по образна диагностика и 8 специализанти. Добитите данни демонстрират преобладаващо позитивна оценка на платформата StatDx в клиниката.StatDx is an online consultation platform for clinical radiologists and diagnostic imaging specialists. It comprises a large database of interconnected articles on diagnoses and differential diagnoses, allowing for quick and intuitive searches, sorting, and comparison between varying disease entities and between their imaging characteristics. This system is richly illustrated with vast amounts of drawings, schematics and imaging studies, all of which comprehensively annotated. StatDx was introduced to the Department of Diagnostic Imaging at St. Marina University Hospital, Varna in early 2017. Over a year later an anonymous internal study was conducted among the physicians using this system – including 14 specialists in Radiology and 8 Radiology interns. The data acquired pointed at a predominantly positive assessment of StatDx at the Department

Breast ultrasound tomography . Novel solutions

Ракът на гърдата според последни проучвания е първото по честота онкологично заболяване при жени в целия свят, както и второто по смъртност за същия пол след белодробния рак. Отбелязвайки спад в честотата на новите случаи в Щатите в годините след 2000-2002 (частично в следствие на редуцираното приложе- ние на хормон-заместителната терапия), ракът на гърдата остава заболяване с огромна социална значимост. Съответно от особена важ- ност са методите за скрининг и диагностика. Диагностичният арсенал нараства с всяка изминала година - от стандартната и дигитална мамография еволюира мамографската томосинтеза, a от ехоскопичното изследване произли- зат два нови томографски метода, напълно лишени от йонизираща радиация, но предоставящи образи с висока информативност. Те биват съответно ехоскопия на цяла гърда (Whole Breast Ultrasound - WBU) и ултразвукова компютърна томография (Ultrasound Computed Tomography - USCT). Първият метод предоставя възможност за идентификация на малки ранни лезии в гърди с висока плътност - находки, трудни за идентификация дори с дигитална мамография. Състои се от апликатор с автоматично движещ се трансдюсер, целящ покриване на цялата тъкан на гърдата и прилежащите зони на интерес - съществуват две технологични разновидности на апликатора. И при двата лаборант асистира за адекватна компресия. Вторият метод не налага компресия - гърдата се поставя в съд с вода, по стените на който са разположени многобройни трансдюсери, добиващи изображения. Последните се реконструират от компютър както при рентгеновата компютърна томография. Стандартните ултразвукови изображения на практика са томографски - без наслагване на съседни структури, но са добити от един-единствен ъгъл. При USCT образът на всеки обект се добива от десетки ъгли, подобрявайки визуализацията.According to recent studies, breast cancer is the oncological disease of highest incidence in women worldwide, as well as the second-highest after pulmonary cancer mortality-wize. Noting a decrease in incidence in the USA in the years after 2000-2002 (partial- ly due to receding use of hormone replacement therapy), breast cancer remains a condition of tremendous social significance. Therefore, special attention is to be given to the methods of screening and diagnostics. The diagnostic arsenal is augmented more and more each year - from analogue and digital mammography stems digital mammographic tomosynthesis, while ultrasonography evolves into two new methods capable of delivering images of high informativeness - also devoid of ionizing radiation. These methods are Whole Breast Ultrasound (WBU) and Ultrasound Computed Tomography (USCT). WBU allows for identification of small early lesions in dense breast tissue - difficult to identify even on digital mammography. It consists of an automatically propelled transducer, which thoroughly scans the breast and adherent zones of interest. Two technological variants of the method exist. Both require a technologist to assist with adequate compression. USCT, on the other hand, does not require compression - the breast is put into a vessel of water, the walls of which are made up of multiple transducers, all yielding images. These images are then reformatted by a computer like in Röntgen-ray CT. Technically, standard ultrasound images are tomographic - no overlap of adjacent structures is present. However, they are yielded from a single angle at a time. USCT images each object from a multitude of angles, improving visualization

Imaging Markers for Staging of Rectal Carcinoma and Restaging after Neoadjuvant Therapy // Образни маркери при стадиране на ректален карцином и рестадиране след неоадювантна терапия

Preoperative staging and follow-up of rectal carcinoma are of utmost importance in modern oncology. This thesis aims to define imaging biomarkers for tumour response and regression before and after neoadjuvant therapy. Imaging of rectal carcinoma is more specific than imaging of other colonic cancers. Rectal cancer staging is based on two principles. The first is an anatomic definition of the tumour, and the second is prognostic stage grouping. Magnet-resonance imaging MRI achieves both. Additional imaging modalities such as ultrasound US, computed tomography CT and positron emission tomography PET are also discussed. This thesis aims to provide the reader with detailed information about imaging of rectal cancer in the context of standardized and novel therapeutic options for this oncologic disease. It is essential to put rectal cancer in the correct stage group based on different imaging markers - local invasion (T-stage), local infiltration of the mesorectum, intra- and extravascular invasion, and lymph node spread. Another important imaging biomarker is the tumour regression grade after neoadjuvant therapy. All markers correspond to substantial oncologic parameters such as survival rates. The magnet-resonance imaging is the bridge connecting all parameters. All factors are described in the context of current therapeutic approaches in rectal carcinoma - neoadjuvant radiation and chemotherapy, total mesorectal excision, and the Watch and Wait strategy.Предоперативното стадиране и проследяването на ректалния рак е от изключителна важност в модерната онкология. Ролята на образната диагностика е ключова. Целта на тази дисертация е да определи образните биомаркери за туморен отговор и регресия преди и след неоадювантна терапия. Образната диагностика на ректалния карцином е по-специфична от тази на другите видове рак на дебелото черво, като се основава на два принципа. Първият е анатомичното определяне на тумора, а вторият е прогностичното групиране на етапи. Това се постига чрез магнитно-резонансна томография, но също са обсъдени и допълнителни образни методи като ултразвук, компютърна томография и позитронно-емисионна томография. Целта на тази дисертация е да предостави подробна информация за изобразяването на ректалния рак в контекста на стандартизирани и нововъзникнали протоколи за терапия на карцинома. От съществено значение е определяне на правилния стадий на базата на различни образни маркери - локална инвазия, локална инфилтрация на мезоректума, интра- и екстраваскуларна инвазия, разпространение в лимфните възли. Друг важен образен биомаркер е степента на регресия на тумора, визуализирана с магнитно-резонансна томография след неоадювантна терапия. Всички маркери са в добра корелация и с онкологични параметри като процент на преживяемост и други. Свързващ мост отново е магнитно-резонансната томография. Всички фактори са описани в контекста на съвременните терапевтични подходи при ректален карцином, а именно неоадюванта лъче- и химиотерапия, тотална мезоректална ексцизия и стратегия на изчакването Watch and Wait

ESR Residents

The presentation provides an overview of some major activities of the Radiology Trainees Forum- the ESR organization for residents. It includes facts about RTF activities, its educational and research schemes and membership benefits. The presentation will focus on the ESR e-learning platform- Training Curriculum, European Diploma in Radiology, European School of Radiology and its annual courses. Other important topics are about the case and poster databases (EURORAD and EPOS) and about the Invest in the Youth Programme- a programme that each year supports young radiologists with free abstract submission and free attendance at the European Congress of Radiology. In addition, the involvement of Bulgarian residents in the RTF will be outlined.

A Novel Approach for Fast Screening of a Complex Cyanobacterial Extract for Immunomodulatory Properties and Antibacterial Activity

The filamentous cyanobacteria from genus Phormidium are rich natural sources of bioactive compounds that could be exploited as pharmaceuticals or nutraceuticals. In this study, we suggest a novel approach for assessing the immunomodulatory properties of the products derived from cyanobacteria. The influence of Phormidium papyraceum extract on the human leukocyte immunophenotype was evaluated by attempting to link this activity to certain putative compounds identified in the extract. By using three staining panels and flow cytometry, we found that the cyanobacterial extract affected mainly CD4+ T cells upregulating activated CD4+CD152+ T cells (15.75 ± 1.93% treated vs. 4.65 ± 1.41% control) and regulatory CD4+CD25+ T cells (5.36 ± 0.64% treated vs. 1.03 ± 0.08% control). Furthermore, P. papyraceum extract can modulate T cell subpopulations with a CD4+ effector/memory phenotype. Extract-treated cells showed increased production of IL-2 (55 ± 12 pg/mL) and IL-6 (493 ± 64 pg/mL) compared to the untreated, 21 ± 7 pg/mL and 250 ± 39 pg/mL, respectively. No significant changes were observed in the secretion of TNF-α. In addition, P. papyraceum extract displayed antibacterial activity against both Gram-negative (inhibition zone from 18.25 ± 0.50 mm to 20.28 ± 1.50 mm) and Gram-positive (inhibition zone from 10.86 ± 0.85 mm to 17.00 ± 0.82 mm) bacteria. The chemical profile of the cyanobacterial extract was determined using LC–ESI–MS/MS analysis, where at least 112 putative compounds were detected. Many of these compounds have proven different biological activities. We speculated that compounds such as betulin and the macrolide azithromycin (or their analogues) could be responsible for the immunomodulatory potential of the investigated extract. More studies are needed to determine and validate the biological activities of the determined putative compounds

Natural Xylooligosaccharides Exert Antitumor Activity via Modulation of Cellular Antioxidant State and TLR4

It has been recently proven that xylooligosaccharides (XOS) with prebiotic properties have diverse beneficial biological effects including immunomodulatory and antitumor activities. The present article focused on the chemical and biological evaluation of corn-derived commercially available XOS and aimed to elucidate their cytotoxicity and inhibitory potential against tumor cells. Spectrophotometric chemical analyses, Fourier transform infrared spectroscopy, and high-performance liquid chromatography analyses were performed. Antioxidant activity was determined by measuring the oxygen radical absorbance capacity and hydroxyl radical averting capacity. In vitro cytotoxicity assays with human cell lines derived from normal and tumor tissues, assessments of ATP production, mitochondrial membrane potential specific staining, cytokine assays, and molecular docking were used to evaluate the biological activity of XOS. The sample showed significant antioxidant activity, and it was determined that most xylose oligomers in it are composed of six units. XOS exhibited antitumor activity with pronounced inhibitory effect on lysosomes, but mitochondrial functionality was also affected. The production of proinflammatory cytokines by lipopolysaccharide-stimulated U-937 cells was reduced by XOS treatment, which suggested the involvement of Toll-like receptor 4 (TLR4)-mediated signaling in the mechanism of XOS action. Molecular docking analyses confirmed the potential inhibitory interaction between the sample and TLR4. In addition, XOS treatment had significant tumor-cell-specific influence on the glutathione antioxidant system, affecting its balance and thus contributing to the inhibition of cellular viability. The present study elucidated the tumor-inhibitory potential of commercially available XOS that could be utilized in pharmaceutical and food industry providing disease-preventive and therapeutic benefits

Molecular Mimicry of the Rheumatoid Arthritis-Related Immunodominant T-Cell Epitope within Type II Collagen (CII260-270) by the Bacterial L-Asparaginase

The etiology of most autoimmune diseases, including rheumatoid arthritis (RA), remains unclear. Both genetic and environmental factors are believed to be involved in pathogenesis. Molecular mimicry is considered one of the mechanisms for the occurrence of autoimmune diseases. The aim of the study was to determine whether the bacterial peptide L-ASNase67-81, which mimics the immunodominant T-cell epitope CII259-273, can induce T-cell reactivity in blood samples from RA patients and healthy subjects through molecular mimicry. Using bioinformatic molecular modeling methods, we first determined whether the L-ASNase67-81 peptide binds to the HLA-DRB1*04:01 molecule and whether the formed MHCII–peptide complex interacts with the corresponding T-cell receptor. To validate the obtained results, leukocytes isolated from early RA patients and healthy individuals were stimulated in vitro with L-ASNase67-81 and CII259-273 peptides as well as with bacterial L-asparaginase or human type II collagen (huCII). The activated T cells (CD4+CD154+) were analyzed by flow cytometry (FACS), and the levels of cytokines produced (IL-2, IL-17A/F, and IFN-γ) were measured by ELISA. Our in silico analyses showed that the bacterial peptide L-ASNase67-81 binds better to HLA-DRB1*04:01 compared to the immunodominant T-cell epitope CII259-273, mimicking its structure and localization in the binding groove of MHCII. Six contact points were involved in the molecular interaction of the peptide with the TCR. FACS data showed that after in vitro stimulation with the L-ASNase67-81 peptide, the percentage of activated T cells (CD154+CD4+) was significantly increased in both cell cultures isolated from ERA patients and those isolated from healthy individuals, as higher values were observed for the ERA group (9.92 ± 0.23 vs. 4.82 ± 0.22). Furthermore, the ELISA assays revealed that after stimulation with L-ASNase67-81, a significant increase in the production of the cytokines IL-2, IL-17A/F, and IFN-γ was detected in the group of ERA patients. Our data showed that the bacterial L-ASNase67-81 peptide can mimic the immunodominant T-cell epitope CII259-273 and activate HLA-DRB1*04:01-restricted T cells as well as induce cytokine production in cells isolated from ERA patients. These results are the first to demonstrate that a specific bacterial antigen could play a role in the pathogenesis of RA, mimicking the immunodominant T-cell epitope from type II collagen

Complete response to chemotherapy in a patient with cholangiocarcinoma of the extrahepatic bile ducts

Introduction: Extrahepatic Cholangiocarcinoma is a rare tumor arising from the biliary epithelium. About two thirds are located at the hepatic duct bifurcation (Klatskin tumor). The overall incidence is about 1 in 100 000 with 3000 new cases annually. Male to female ratio is 1.3:1 and the average age of the patients is between 50-70 years old. Most patients with unresectable disease die within one year of the diagnosis. The average five-year survival rate of resectable ones is between 10-30 %, while in unresectable ones it is less than five.Materials and methods: A case of a 48-year-old patient with cholangiocarcinoma of the extrahepatic bile ducts is presented. He was first admitted to the Infectious Disease Department at St. Marina UniversityHospital Varna with jaundice, general weakness and vomiting. The patient underwent different diagnostic modalities such as ultrasonography, computed tomography and magnetic resonance imaging. A neoplastic process was suspected. An exploratory surgery was therefore performed which deemed the patient unresectable and after that an open biopsy confirmed a T4NxMx cholangiocarcinoma of the extrahepatic bile ducts.Results: Currently surgical excision is the only potentially curative treatment for cholangiocarcinoma.Patients with unresectable disease are often offered treatment with GEMCIS - a combination of gemcitabine and cisplatin; GEMOX - a combination of gemcitabine and oxaliplatin; monotherapy with gemcitabine or therapy with leucovorin and fluoropyrimidines. The Oncological Committee decided to subject the patient to first line of chemotherapy consisting of four cycles of GEMOX. Following that, computed tomography showed signs of stable disease and it was decided to continue the treatment with three more cycles. After the last course of chemotherapy, positron emission tomography showed that the tumor had disappeared.Conclusion: Extrahepatic cholangiocarcinoma is a devastating disease that rarely responds to chemotherapy.That being said, the presented case is a miraculous exception of a complete remission