Biocompatible Upconverting Nanoprobes for Dual-Modal Imaging and Temperature Sensing.

The demand for multimodal nanomaterials has intensified in recent years driven by the need for ultrasensitive bioimaging probes and accurate temperature monitoring in biological objects. Among the different multimodal nanomaterials that have been extensively studied in the past decade, upconverting nanoparticles are among the most promising. In this paper, we report the synthesis of upconverting nanoparticles with complex core-shell compositions, capable of being excited by 808 or 980 nm laser irradiation and exhibiting a good MRI response. The synthesized nanoparticles also demonstrated high colloidal stability in both aqueous and biological media as well as temperature-sensing capabilities, including the physiological range. Furthermore, the upconversion nanoparticles exhibited significantly lower cytotoxicity for HEK293T cells than the commercially available MRI contrast agent Gd-DTPA.

Efficacy of focal high-dose-rate brachytherapy in the treatment of patients diagnosed with low or favourable: intermediate-risk prostate cancer-a protocol for a randomised controlled trial.

INTRODUCTION: Prostate cancer (PCa) is men's second most predominant cancer worldwide. Because the prostate-specific antigen test is used in diagnostics, PCa is more often diagnosed in the early stages, making radical treatment of the disease possible. However, it is estimated that over a million men worldwide suffer from radical treatment-related complications. Thus, focal treatment has been proposed as a solution, which aims to destroy the predominant lesson that determines the progression of the disease. The main objective of our study is to compare the quality of life and efficacy of patients diagnosed with PCa before and after the treatment with focal high-dose-rate brachytherapy and to compare results with focal low-dose-rate brachytherapy and active surveillance. METHODS AND ANALYSIS: 150 patients diagnosed with low-risk or favourable intermediate-risk PCa who meet the inclusion criteria will be enrolled in the study. Patients are going to be randomly assigned to the study groups: focal high-dose-rate brachytherapy (group 1), focal low-dose-rate brachytherapy (group 2) and active surveillance (group 3). The study's primary outcomes are quality of life after the procedure and time without biochemical disease recurrence. The secondary outcomes are early and late genitourinary and gastrointestinal reactions after the focal high-dose and low-dose-rate brachytherapies and evaluation of the importance and significance of in vivo dosimetry used for high-dose-rate brachytherapy. ETHICS AND DISSEMINATION: Bioethics committee approval was obtained before this study. The trial results will be published in peer-reviewed journals and at conferences. TRIAL REGISTRATION NUMBER: Vilnius regional bioethics committee; approval ID 2022/6-1438-911.

Blood direct PCR: impact of CYP2C19 and CYP4F2 variants for bleeding prediction in ST-elevation myocardial infarction patients with ticagrelor.

Aims: The goals of this study were to develop a new technique that could pave the way for a quicker determination of CYP4F2 rs3093135 and CYP2C19 rs4244285 variants directly from a patient's blood and to attempt to apply this technique in clinical practice. Patients & methods: The study included 144 consecutive patients admitted with ST elevation myocardial infarction. A blood-direct PCR and real-time PCR were used to detect variants of interest. Results & conclusion: Patients with bleeding events had the CYP2C19 GG (*1*1) variant more frequently than patients without bleeding events. The CYP4F2 TT variant was more frequently detected in patients with bleeding events 3 months after hospitalization.

Ticagrelor is one of the main antiplatelet drugs used for prevention of coronary blood clots after interventional procedures in patients with acute coronary syndromes. It has previously been shown that gene variants of CYP2C19 and CYP4F2 may affect antiplatelet therapy. This paper reports a novel instrument and the results of genetic tests obtained using this instrument. Our instrument can detect variants of the genes associated with ticagrelor antiplatelet therapy in only 40 min. These findings might facilitate individualized treatment with ticagrelor of patients with ST-elevation myocardial infarction.

The Impact of the COVID-19 Pandemic on Cancer Patient's Management-Lithuanian Cancer Center Experience.

The pandemic spread of the COVID-19 virus significantly affected daily life, but the highest pressure was piled on the health care system. Our aim was to evaluate an impact of COVID-19 pandemic management measures on cancer services at the National Cancer Institute (NCI) of Lithuania. We assessed the time period from 1 February 2020 to 31 December 2020 and compared it to the same period of 2019. Data for our analysis were extracted from the NCI Hospital Information System (HIS) and the National Health Insurance Fund (NHIF). Contingency table analysis and ANOVA were performed. The COVID-19 pandemic negatively affected the cancer services provided by NCI. Reductions in diagnostic radiology (-16%) and endoscopy (-29%) procedures were accompanied by a decreased number of patients with ongoing medical (-30%), radiation (-6%) or surgical (-10%) treatment. The changes in the number of newly diagnosed cancer patients were dependent on tumor type and disease stage, showing a rise in advanced disease at diagnosis already during the early period of the first lockdown. The extent of out-patient consultations (-14%) and disease follow-up visits (-16%) was also affected by the pandemic, and only referrals to psychological/psychiatric counselling were increased. Additionally, the COVID-19 pandemic had an impact on the structure of cancer services by fostering the application of modified systemic anticancer therapy or hypofractionated radiotherapy. The most dramatic drop occurred in the number of patients participating in cancer prevention programs; the loss was 25% for colon cancer and 62% for breast cancer screening. Marked restriction in access to preventive cancer screening and overall reduction of the whole spectrum of cancer services may negatively affect cancer survival measures in the nearest future.

Acute Radiation Dermatitis Evaluation with Reflectance Confocal Microscopy: A Prospective Study.

BACKGROUND: During radiotherapy (RT), most breast cancer patients experience ionizing radiation (IR)-induced skin injury-acute radiation dermatitis (ARD). The severity of ARD is determined by a physician according to CTCAE or RTOG scales, which are subjective. Reflectance confocal microscopy (RCM) is a noninvasive skin imaging technique offering cellular resolution. Digital dermoscopy (DD) performed in conjugation with RCM can provide more information regarding skin toxicity. The purpose of this study is to create an RCM and DD features-based ARD assessment scale, to assess the association with CTCAE scale and possible predictive value. METHODS: One hundred and three breast cancer patients during RT were recruited; every week, clinical symptoms of ARD (CTCAE scale) were evaluated and RCM, together with digital dermoscopy (DD), was performed. RESULTS: According to RCM; after 2 RT weeks, exocytosis and/or spongiosis were present in 94% of patients; after 3 weeks, mild contrast cells (MMCs) were detected in 45%; disarrayed epidermis (DE) was present in 66% of patients after 4 weeks and in 93% after 5 weeks; abnormal dermal papillae (ADP) were present in 68% of patients after 5 weeks. The coefficients of RCM features (RCMcoef) alone and together with dermoscopically determined erythema (RCM-ERYcoef) were significantly associated with ARD severity grade. RCMcoef is a significant predictive factor for the clinical manifestation of ARD. CONCLUSIONS: RCM features of irradiated skin appear earlier than clinical symptoms, have a characteristic course, and allow the severity of ARD to be predicted.

A Pilot Study of Safer Radiation Dosage to the Heart and Its Subregions.

Background and Objectives: The real impact of ionizing radiation on the heart and poorer overall survival for patients with non small cell lung cancer (NSCLC) remains unclear. This study aims to determine the safe dose constraints to the heart's subregions that could prevent patients' early non-cancerous death and improve their quality of life. Methods and Materials: A retrospective cohort study was performed containing 51 consecutive patients diagnosed with stage III NSCLC and treated using 3D, Intensity-modulated radiation therapy (IMRT), and Volumetric modulated arc therapy (VMAT) radiotherapy. For a dosimetric analysis, these structures were chosen: heart, heart base (HB), and region of great blood vessels (GBV). Dose-volume histograms (DVH) were recorded for all mentioned structures. Maximum and mean doses to the heart, HB, the muscle mass of the HB, and GBV were obtained. V10-V60 (%) parameters were calculated from the DVH. After performed statistical analysis, logistic regression models were created, and critical doses calculated. Results: The critical dose for developing a fatal endpoint for HB was 30.5 Gy, while for GBV, it was 46.3 Gy. Increasing the average dose to the HB or GBV by 1 Gy from the critical dose further increases the possibility of early death by 22.0% and 15.8%, respectively. Conclusions: We suggest that the non-canonical sub-regions of the heart (HB and GBV) should be considered during the planning stage. Additional constraints of the heart subregions should be chosen accordingly, and we propose that the mean doses to these regions be 30.5 Gy and 46.3 Gy, respectively, or less. Extrapolated DVH curves for both regions may be used during the planning stage with care.

Individual Radiosensitivity as a Risk Factor for the Radiation-Induced Acute Radiodermatitis.

BACKGROUND: Up to 95% of irradiated patients suffer from ionizing radiation (IR) induced early skin reaction, acute radiation dermatitis (ARD). Some experts think that additional skin hydration can reduce acute skin reactions. Individual radiosensitivity (IRS) determined from lymphocytes may help to predict acute radiation toxicity. The purpose of this study is to evaluate the clinical manifestation of ARD in different skincare groups during whole breast radiotherapy depending on IRS and other risk factors. METHODS: A total of 108 early-stage breast cancer patients were randomized into best supportive care (BSC) and additional skincare (ASC) groups. IRS was evaluated using a G2 assay modified with caffeine-induced G2 checkpoint arrest. All patients received a 50 Gy dose to the breast planning target volume (PTV). Clinical assessment of ARD symptoms according to the CTCAE grading scale was performed once a week. RESULTS: IRS was successfully determined for 91 out of 108 patients. A total of 10 patients (11%) had normal IRS, 47 patients (52%) were categorized as radiosensitive, and 34 (37%) as highly radiosensitive. There was no significant difference in the manifestation of ARD between patient groups by skincare or IRS. According to logistic regression, patients with bigger breasts were prone to more severe ARD (p = 0.002). CONCLUSIONS: The additional skincare did not improve skin condition during RT. A total of 89% of patients had increased radiosensitivity. IRS determined before RT did not show the predictive value for the manifestation of ARD. Logistic regression revealed that breast volume was the most significant risk factor for the manifestation of ARD.

Polar organization of collagen in human cardiac tissue revealed with polarimetric second-harmonic generation microscopy.

Polarimetric second-harmonic generation (P-SHG) microscopy is used to characterize the composition and polarity of collagen fibers in various regions of human cardiac tissue. The boundary between the cardiac conduction system and myocardium is shown to possess a distinct composition of collagen compared to other regions in the heart. Moreover, collagen fibers in this region are macroscopically organized in a unipolar arrangement, which may consequently aid in effective propagation of the electrical signal through the cardiac conduction system.

Image based simulation of the low dose computed tomography images suggests 13 mAs 120 kV suitability for non-syndromic craniosynostosis diagnosis without iterative reconstruction algorithms.

OBJECTIVES: The aim of this study was to simulate low dose paediatric head CT images with different noise levels corresponding to various tube current time product values and assess simulated image suitability in non-syndromic craniosynostosis diagnostics. METHOD: 29 paediatric patients who underwent head CT examinations for cranial deformity were enrolled in the study. The low dose CT images, corresponding to 120 kV and 120 mAs, 100 mAs, 80 mAs, 50 mAs and 13 mAs settings, were synthesised by adding noise to original data. Three researchers evaluated suitability for diagnostics of original and simulated images by using questionnaire assessing image suitability. RESULT: 174 separate cases (containing 1 axial and 1 3D image) were evaluated. Percentage of images evaluated as suitable for diagnosis were 98.9% on original images, 100% on 120 mAs, 100% on 100 mAs, 97.1% on 80 mAs, 96.6% on 50 mAs and 96% on 13 mAs. CONCLUSIONS: Images registered with 120 kV 13 mAs can be used to diagnose non-syndromic craniosynostosis with statistically same accuracy as with standard protocol and correspond to decrease of effective dose from 4.98 mSv to 0.33 mSv (median values).

Microenvironment and Dose-Delivery-Dependent Response after Exposure to Ionizing Radiation in Human Colorectal Cancer Cell Lines.

A significant body of knowledge about radiobiology is based on studies of single dose cellular irradiation, despite the fact that conventional clinical applications using dose fractionation. In addition, cellular radiation response strongly depends on cell-cell and cell-extracellular matrix (ECM) interactions, which are poorly established in cancer cells grown under standard 2D cell culture conditions. In this study, we investigated the response of human colorectal carcinoma (CRC) DLD1 and HT29 cell lines, bearing distinct p53 mutations, to a single 2 or 10 Gy dose or fractionated 5 × 2 Gy doses of radiation using global transcriptomics analysis. To examine cellular response to radiation in a cell-ECM-interaction-dependent manner, CRC cells were grown under laminin-rich ECM 3D cell culture conditions. Microarray data analysis revealed that, overall, a total of 1,573 and 935 genes were differentially expressed (fold change >1.5; P < 0.05) in DLD1 and HT29 cells, respectively, at 4 h postirradiation. However, compared to a single dose of radiation, fractionated doses resulted in significantly different transcriptomic response in both CRC cell lines. Furthermore, pathway enrichment analysis indicated that p53 pathway and cell cycle/DNA damage repair or immune response functional categories were most significantly altered in DLD1 or HT29 cells, respectively, after fractionated irradiations. Novel observations of radiation-response-mediated activation of pro-survival pathways in CRC cells grown under lr-ECM 3D cell culture conditions using fractionated doses provide new directions for the development of more efficient radiotherapy strategies. Our results also indicated that cell line specific radiation response with or without activation of the conventional p53 pathway is ECM dependent, suggesting that the ECM is a key component in cellular radiation response.

Optimal differentiation of high- and low-grade glioma and metastasis: a meta-analysis of perfusion, diffusion, and spectroscopy metrics.

INTRODUCTION: To perform a meta-analysis of advanced magnetic resonance imaging (MRI) metrics, including relative cerebral blood volume (rCBV), normalized apparent diffusion coefficient (nADC), and spectroscopy ratios choline/creatine (Cho/Cr) and choline/N-acetyl aspartate (Cho/NAA), for the differentiation of high- and low-grade gliomas (HGG, LGG) and metastases (MTS). METHODS: For systematic review, 83 articles (dated 2000-2013) were selected from the NCBI database. Twenty-four, twenty-two, and eight articles were included respectively for spectroscopy, rCBV, and nADC meta-analysis. In the meta-analysis, we calculated overall means for rCBV, nADC, Cho/Cr (short TE-from 20 to 35 ms, medium-from 135 to 144 ms), and Cho/NAA for the HGG, LGG, and MTS groups. We used random effects model to obtain weighted averages and select thresholds. RESULTS: Overall means (with 95% CI) for rCBV, nADC, Cho/Cr (short and medium echo time, TE), and Cho/NAA were: for HGG 5.47 (4.78-6.15), 1.38 (1.16-1.60), 2.40 (1.67-3.13), 3.27 (2.78-3.77), and 4.71 (3.24-6.19); for LGG 2.00 (1.71-2.28), 1.61 (1.36-1.87), 1.46 (1.20-1.72), 1.71 (1.49-1.93), and 2.36 (1.50-3.23); for MTS 5.06 (3.85-6.27), 1.35 (1.06-1.64), 1.89 (1.72-2.06), 3.14 (1.57-4.72), (Cho/NAA was not available). LGG had significantly lower rCBV, Cho/Cr, and Cho/NAA values than HGG or MTS. No significant differences were found for nADC. CONCLUSIONS: Best differentiation between HGG and LGG is obtained from rCBV, Cho/Cr, and Cho/NAA metrics. MTS could not be reliably distinguished from HGG by the methods investigated.

5-aminolevulinic-acid-based fluorescence spectroscopy and conventional colposcopy for in vivo detection of cervical pre-malignancy.

BACKGROUND: Sensitized fluorescence diagnostics are based on selective accumulation of photosensitizer in the tissue where carcinogenesis has started. The present study compared topical 5-aminolevulinic acid (5-ALA)-based fluorescence spectroscopy (FS) in vivo with conventional colposcopy for cervical intraepithelial neoplasia (CIN) detection. METHODS: We enrolled 48 patients who were referred for colposcopy because of high-grade changes in cervical cytology. Every inspected cervix was divided in to quadrants, and there were 174 quadrants included in the study. Each patient had a cytological smear, colposcopy, FS and histopathological analysis. For FS, 3% 5-ALA cream was used topically and after an average 135 min incubation, fluorescence spectra were recorded from the cervix in vivo. FS and colposcopy results were correlated with histopathology. RESULTS: All spectra were evaluated by a ratio of the protoporphyrin IX fluorescence intensity at 634 nm and autofluorescence intensity at 510 nm. For proper grouping of low-risk and high-risk cases, a threshold of 3.87 was calculated. Data per quadrant showed that FS had higher sensitivity than colposcopy (71.7% vs 67.4%) but specificity was greater for colposcopy (86.6% vs 75.6%). Combination of the methods showed higher sensitivity (88.0% vs 67.4%) but reduced specificity (88.0% and 69.5%), but it had the highest number of correctly identified high-risk changes and the highest (79.3%) accuracy. Data for each patient showed FS sensitivity of 91.2%, which was greater than for colposcopy (88.2%). Higher overdiagnosis resulted in decreased specificity for fluorescence methodology-71.4% versus 78.6% for colposcopy. In both cases, accuracy was 85.4% and effectiveness was >80%, which means that both methods can be used to determine high-risk cervical intraepithelial neoplasia. The diagnostic sensitivity of 97.1% for this complementary diagnosis indicates that it could be the best choice for detection of high-risk changes. CONCLUSIONS: 5-ALA-based FS is an objective method, requiring short-term administration for appropriate fluorescence measurements. FS is a promising diagnostic tool with similar accuracy as colposcopy but with the potential advantage of providing objective results.

Nevomelanocytic atypia detection by in vivo reflectance confocal microscopy.

BACKGROUND AND OBJECTIVE: In vivo reflectance confocal microscopy (RCM) is a promising novel technology for non-invasive early diagnostics of cutaneous melanoma. However, the possibility to detect melanocytic atypia in nevi by means of in vivo RCM remains unknown. The aim of the study was to evaluate the significance of in vivo RCM features of melanocytic atypia for the diagnosis of melanocytic nevi, dysplastic nevi and cutaneous melanoma. MATERIALS AND METHODS: A total of 138 melanocytic skin lesions comprising 25 melanocytic nevi, 69 dysplastic nevi and 44 melanomas were analyzed by means of dermoscopy, in vivo RCM and routine histopathology. In vivo RCM images were analyzed for the arrangement of keratinocytes in epidermis, pagetoid cells and junctional melanocytic nests and correlated refractivity aspects of nests with histopathology. RESULTS: Separately and all together taken the in vivo RCM features of melanocytic atypia were significant in differential diagnosis of benign and malignant melanocytic skin lesions, though none of the features was significant in discriminating nevi without cytologic atypia of dysplastic nevi. In vivo RCM feature of dense cell clusters corresponded with melanin containing nevomelanocytes on histopathology though exact correspondence of non-homogeneous and atypical sparse cell clusters remained questionable. CONCLUSIONS: Nevus with histopathologically confirmed nevomelanocytic atypia (dysplastic nevus) could not be distinguished from nevus without atypia using analyzed in vivo RCM features of melanocytic atypia. More accurate diagnostics by means of in vivo RCM needs further investigation on reflectance of single and nested cutaneous melanocytes in benign and malignant skin lesions.

5-Aminolevulinic acid-based fluorescence diagnostics of cervical preinvasive changes.

The purpose of this article is to review the diagnostic possibilities of 5-aminolevulinic acid (5-ALA)-based fluorescence diagnosis of preinvasive cervical changes. Reviewed papers were selected from the PubMed database with keywords combining the terms individual cervical neoplasia and fluorescence diagnostics. The regular colposcopy procedure lacks specificity; therefore, new methods are continually sought for superior diagnosis of cervical pathology. 5-ALA-based fluorescence diagnostics is under investigation as an up-to-date diagnostic technique for cervical intraepithelial neoplasia (CIN). This method is grounded on the topical or systemic application of 5-ALA, which induces excess production of the endogenous photosensitizer protoporphyrin IX (PpIX) in tissues where carcinogenesis has begun. The conversion of PpIX to the heme is less efficient in tumors; therefore, higher amounts of PpIX tend to accumulate in premalignant and malignant tissues. Illumination with light of the appropriate wavelength initiates excitation of PpIX fluorescence, which in turn helps to localize PpIX-rich areas and identify potentially malignant tissues. A number of investigations suggest that because of its high selectivity for tumors and low toxicity to healthy tissues, 5-ALA-based diagnosis seems a promising tool for the noninvasive identification of cervical intraepithelial neoplasia.

High resolution imaging of the human cardiac conduction system using reflectance confocal microscopy.

Rhythmical contraction of the heart is controlled by the cardiac conduction system (CCS) that consists of the three main parts: the sino-atrial node, the atrioventricular node and the His-Purkinje system. A heartbeat signal, originated from CCS, spreads through its branches to the different parts of the heart, initiating depolarization of the ventricles. However, this highly important system could not be distinguished visually from the surrounding heart tissues: myocardium (MC) and connective tissue (CT). Thus, during surgical procedures, CCS could be easily damaged; namely, the reliable method for identification of CCS either in vivo or ex vivo does not exist. Accordingly, there is a definite need for developing a CCS imaging method. Reflection confocal microscopy (RCM) offers non-destructive imaging of the tissue at depths of up to 0.35 mm with the capability of identification of a single cell. During the visualization procedure, a given tissue is illuminated with infrared laser light and the image is obtained because of different reflections from the tissue structures. However, the reflective structures in the heart tissues are still not identified. In the present study, for the first time we investigated cardiac tissues by RCM. The resolution of the method allowed us to distinguish MC cells and CCS cells. The method also allowed us to distinguish the network-like structures that are main components of CT. The ability to visualize different tissue components indicates a great potential for RCM to be used in non-destructive cardiac investigations and for imaging CCS.

Visualization of human heart conduction system by means of fluorescence spectroscopy.

The conduction system of the heart is a specific muscular tissue, where a heartbeat signal originates and initiates the depolarization of the ventricles. The muscular origin makes it complicated to distinguish the conduction system from the surrounding tissues. A surgical intervention can lead to the accidental harm of the conduction system, which may eventually result in a dangerous obstruction of the heart functionality. Therefore, there is an immense necessity for developing a helpful method to visualize the conduction system during the operation time. The specimens for the spectroscopic studies were taken from nine diverse human hearts. The localization of distinct types of the tissue was preliminary marked by the pathologist and approved histologically after the spectral measurements. Variations in intensity, as well as in shape, were detected in autofluorescence spectra of different heart tissues. The most distinct differences were observed between the heart conduction system and the surrounding tissues under 330 and 380 nm excitation. The spectral region around 460 nm appeared to be the most suitable for an unambiguous differentiation of the human conduction system avoiding the absorption peak of blood. The visualization method, based on the intensity ratios calculated for two excitation wavelengths, was also demonstrated.