Objectives Reconstructing images from measurements with small pixels below the system's resolution limit theoretically results in image noise reduction compared with measurements with larger pixels. We evaluate and quantify this effect using data acquired with the small pixels of a photon-counting (PC) computed tomography scanner that can be operated in different detector pixel binning modes and with a conventional energy-integrating (EI) detector. Materials and Methods An anthropomorphic abdominal phantom that can be extended to 3 sizes by adding fat extension rings, equipped with iodine inserts as well as human cadavers, was measured at tube voltages ranging from 80 to 140 kV. The images were acquired with the EI detector (0.6 mm pixel size at isocenter) and the PC detector operating in Macro mode (0.5 mm pixel size at iso) and ultrahigh-resolution (UHR) mode (0.25 mm pixel size at iso). Both detectors are components of the same dual-source prototype computed tomography system. During reconstruction, the modulation transfer functions were matched to the one of the EI detector. The dose-normalized contrast-to-noise ratio (CNRD) values are evaluated as a figure of merit. Results Images acquired in UHR mode achieve on average approximately 6% higher CNRD compared with Macro mode at the same spatial resolution for a quantitative D40f kernel. Using a sharper B70f kernel, the improvement increases to 21% on average. In addition, the better performance of PC detectors compared with EI detectors with regard to iodine imaging has been evaluated by comparing CNRD values for Macro and EI. Combining both of these effects, a CNRD improvement of up to 34%, corresponding to a potential dose reduction of up to 43%, can be achieved for D40f. Conclusions Reconstruction of UHR data with a modulation transfer function below the system's resolution limit reduces image noise for all patient sizes and tube voltages compared with standard acquisitions. Thus, a relevant dose reduction may be clinically possible while maintaining image quality.
Toxic metals are extensively found in the environment, households, and workplaces and contaminate food and drinking water. The crosstalk between environmental exposure to toxic metals and human diseases has been frequently described. The toxic mechanism of action was classically viewed as the ability to dysregulate the redox status, production of inflammatory mediators and alteration of mitochondrial function. Recently, growing evidence showed that heavy metals might exert their toxicity through microRNAs (miRNA)-short, single-stranded, noncoding molecules that function as positive/negative regulators of gene expression. Aberrant alteration of the endogenous miRNA has been directly implicated in various pathophysiological conditions and signaling pathways, consequently leading to different types of cancer and human diseases. Additionally, the gene-regulatory capacity of miRNAs is particularly valuable in the brain-a complex organ with neurons demonstrating a significant ability to adapt following environmental stimuli. Accordingly, dysregulated miRNAs identified in patients suffering from neurological diseases might serve as biomarkers for the earlier diagnosis and monitoring of disease progression. This review will greatly emphasize the effect of the toxic metals on human miRNA activities and how this contributes to progression of diseases such as cancer and neurodegenerative disorders (NDDs).
The purpose of the present study was to evaluate the incidence, spectrum and extent of psychiatric symptoms in patients with malignant melanoma (MM) before and during adjuvant treatment with interferon-alpha (IFN-alpha). 850 patients with cutaneous MM of > or =1.5 mm tumor thickness received standard low-dose IFN-alpha 2a in this prospective multicenter trial of the Dermatologic Cooperative Oncology Group (DeCOG). Psychiatric symptoms were evaluated at baseline and after 3, 6, and 12 months with the Beck Depression Inventory (BDI) and the Symptom Check List 90-Revised (SCL 90-R). In all, 282 patients completed all questionnaires. Mean BDI depression scores increased significantly during the first 6 months of IFN-alpha treatment (P < or =0.001), followed by a mild but not significant decrease. Also mean SCL 90-R scores increased significantly during the first 3 months of adjuvant treatment with IFN-alpha (P< or =0.001) and remained elevated until month 12 (P< or =0.001). Only 5% developed BDI scores >10, indicating a clinically significant depressive syndrome and only 1.4% reached a BDI score > or =18, indicating a moderate to severe depressive syndrome. Patients, who dropped-out early from psychiatric reasons, had significantly increased BDI and SCL-90R scores at baseline. Women scored higher in both scales before and during treatment if compared with men. In conclusion, adjuvant treatment with IFN-alpha was associated with a significant increase of BDI- and SCL 90-R scores. A higher pretreatment depression score was found to be a risk factor for an early drop-out during therapy. Pretreatment screening and an interdisciplinary care of the patients is recommended.
Post-mortem animal depredation is not an uncommon phenomenon in routine forensic autopsies. We present three cases of complete post-mortem decapitation by domestic German shepherd dogs. In two cases, the head had been bitten off, defleshed and left lying near the body, while in one case it had been completely devoured by two dogs; only small skull fragments and crowned teeth could be found. Two of the three bodies were putrefied; all dog bite injuries had been inflicted after death. The cause of death was drug toxicity in two cases and fatal hemorrhage from ruptured esophageal varices in one case. These rare injuries due to post-mortem animal depredation are discussed in the light of earlier studies and case reports.
Adjuvant treatment with interferon-α (IFN-α) for patients with malignant melanoma can improve relapse-free and overall survival, but IFN-associated side effects may reduce patient's quality of life. The aim of the study was to prospectively evaluate health-related quality of life (HRQoL) in patients with melanoma before and during Low-Dose IFN-α therapy. In a prospective multicenter trial conducted by the Dermatologic Cooperative Oncology Group, 850 patients with cutaneous stage II malignant melanoma received a standard Low-Dose of IFN-α-2a. We evaluated HRQoL using the European Organization for Research and Treatment of Cancer Quality of Life Core 30 questionnaire at baseline and after 3, 6, and 12 months of IFN-α treatment in 282 patients. Nine of 15 subscales showed significant poorer results after 3 months of adjuvant IFN treatment. Symptoms included reduced physical functioning, reduced cognitive functioning, fatigue, nausea, pain, dyspnea, insomnia, diarrhea, and loss of appetite. We did not find a significant change over time for role, emotional, or social functioning. Only cognitive functioning and dyspnea continuously worsened through the twelfth month. At baseline women had significantly lower scores for physical and emotional functioning and for fatigue compared with men. During treatment, women scored significantly poorer on physical functioning, emotional functioning, fatigue, pain, and constipation subscales. Patients who reported having a bad or very bad QoL before treatment were 5.8 times more likely to discontinue treatment early because of psychiatric problems. We conclude that adjuvant low-dose IFN treatment is associated with significant deterioration of HRQoL. Specific psychosocial care should be offered especially for patients who report lower HRQoL and emotional problems before treatment to prevent early discontinuation.
Clinician-performed chest ultrasound is rapidly entering clinical practice in the fields of intensive care, respiratory medicine and acute medicine. Ultrasound is clearly useful in the diagnosis and characterisation of pleural diseases. It is also critical in improving the safety of pleural interventions. More recently, attention has also focused on the use of lung ultrasound. While the normal aerated lung is not well imaged by ultrasound, lung pathology reaching the pleura often provides an 'acoustic window' for a number of lung conditions. Lung ultrasound is useful to diagnose pneumothorax, interstitial and alveolar lung abnormalities, and pleurally based lung masses. There is some evidence that integrating routine chest ultrasound into clinical practice has benefit in the emergency and intensive care settings. In the future, chest ultrasound is likely to become an essential physician skill, and training requirements are evolving in light of current developments.
An evaluation of energy thresholding and acquisition mode for metal artifact reduction in Photon-counting detector CT (PCD-CT) compared to conventional energy-integrating detector CT (EID-CT) was performed. Images of a hip prosthesis phantom placed in a water bath were acquired on a scanner with PCD-CT and EID-CT (tube potentials: 100, 120 and 140 kVp) and energy thresholds (above 55–75 keV) in Macro and Chess mode. Only high-energy threshold images (HTI) were used. Metal artifacts were quantified by a semi-automated segmentation algorithm, calculating artifact volumes, means and standard deviations of CT numbers. Images of a human cadaver with hip prosthesis were acquired on the PCD-CT in Macro mode as proof-of-concept. Images at 140 kVp showed less metal artifacts than 120 kVp or 100 kVp. HTI (70, 75 keV) had fewer artifacts than low energy thresholds (55, 60, 65 keV). Fewer artifacts were observed in the Macro-HTI (8.9–13.3%) for cortical bone compared to Chess-HTI (9.4–19.1%) and EID-CT (10.7–19.0%) whereas in bone marrow Chess-HTI (19.9–45.1%) showed less artifacts compared to Macro-HTI (21.9–38.3%) and EID-CT (36.4–54.9%). Noise for PCD-CT (56–81 HU) was higher than EID-CT (33–36 HU) irrespective of tube potential. High-energy thresholding could be used for metal artifact reduction in PCD-CT, but further investigation of acquisition modes depending on target structure is required.
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