Utility of MRI in detection of PET-CT proven local recurrence of pancreatic adenocarcinoma after surgery

The aim of this prospective study was to investigate the accuracy and inter-observer reliability of MRI in detection of local recurrence (LR) of pancreatic adenocarcinoma (PAC) after surgery, which was proved by PET-CT and access correlation between functional MRI and PET parameters. Forty-five patients who underwent PET-CT and MRI for follow-up purposes after radical operation of PAC were included. Twenty-three were PET positive (study group) and 22 negative for LR (control group). MR examination was performed within one month after PET-CT and three readers who were blind for PET-CT findings searched LR in T2W, 3D-dynamic post-contrast T1W-FS and DWI sequences, respectively. Sensitivity and specificity were calculated while inter-reader agreement was estimated by Cronbach's Alpha reliability coefficient (CARC). Apparent diffusion coefficient (ADC) of LR was correlated with the size (maximal diameter) and functional PET-CT parameters: mean and maximum standardized uptake values (SUVmean, SUVmax), metabolic tumor volume (MTV) and total lesion glycolysis (TLG), using Spearman's correlation coefficient (rS). Sensitivity and specificity among three readers in detecting the LR were 70% and 77-84% in T2W (CARC 0.806), 91-100% and 100% in 3D post-contrast T1W-FS (CARC 0.980), and both 100% in DWI sequences (CARC 1.000). Moderate inverse correlation was found between the ADC and SUVmean (rS = - 0.484), MTV (rS = - 0.494), TLG (rS = - 0.519) and lesion size (rS = - 0.567). MRI with DWI shows high diagnostic accuracy in detecting the LR of PAC in comparison to PET-CT as reference standard. ADC significantly inversely correlates with standard and advanced PET parameters and size of LR.

Relative risk for cardiovascular morbidity in hemodialysis patients regarding gene polymorphism for IL-10, IL-6, and TNF

Uremia-related inflammation is prone to be a key factor to explain high cardiovascular morbidity in hemodialysis patients. Genetic susceptibility may be of importance, including IL-10, IL-6, and TNF. The aim was to analyze IL-10, IL-6, and TNF gene polymorphisms in a group of hemodialysis patients and to correlate the findings with cardiovascular morbidity. This study included 169 patients on regular hemodialysis at Zvezdara University Medical Center. Gene polymorphisms for IL-10, IL-6 and TNF were determined using PCR. These findings were correlated with the cardiovascular morbidity data from patient histories. Heterozygots for IL-10 gene showed significantly lower incidence of cardiovascular events (p = 0.05) and twice lower risk for development of myocardial infarction, but experienced twice higher risk for left ventricular hypertrophy. Regarding TNF gene polymorphism, patients with A allele had 1.5-fold higher risk for cerebrovascular accident and cardiovascular events and 2-fold higher risk for hypertension and peripheral vascular disease. Patients with G allele of IL-6 gene experienced 1.5-fold higher risks for cerebrovascular accident. We need studies with larger number of patients for definitive conclusion about the influence of gene polymorphisms on cardiovascular morbidity in hemodialysis patients and its importance in everyday clinical practice.

Interobserver variability and positive predictive value for ultrasonographic BI-RADS categories requiring pathohistological evaluation

OBJECTIVE

The objective of this study was an analysis of interobserver variability and positive predictive value (PPV) for BI-RADS categories requiring pathohistological evaluation: 4A, 4B, 4C, and 5.

MATERIAL AND METHODS

Interobserver variability for each of descriptors as well as PPV for final BI-RADS categories requiring pathohistological evaluation was measured in a retrospective study which included 30 ultrasonographic reports, with pathohistological verification, randomly selected from ultrasonographic reports from Institute for Oncology and Radiology of Serbia where about 1,100 breast cancers are verified every year. Ten observers, seven gynecologists, and three radiologists, independently rated each ultrasonographic report according to the fourth edition of BI-RADS atlas. Interobserver variability was measured with k coefficient.

RESULTS

There was most conformity for a category of orientation (k = 0.79). Substantial degree of conformity was also present for both boundary (k = 0.71) and shape (k = 0.65) categories. Moderate degree of conformity was achieved for posterior features (k = 0.54) and margins (k = 0.41) descriptors, while there was poor conformity in echogenicity (k = 0.38). In case of a final score, common conformity for all BI-RADS 4A, 4B, 4C, and 5 categories was (k = 0.51); it was the greatest for category 5 (k = 0.50), and it was less for categories 4C (k = 0.37), 4B (k = 0.32), and 4A (k = 0.29).

CONCLUSIONS

Interobserver conformity for ultrasonographic descriptors and final evaluation of BI-RADS 4A, 4B, 4C, and 5 categories is good. PPV implies that not only division into categories 4 and 5, but also classification into categories 4 and subcategories 4A, 4B, and 4C are justified and clinically applicable.

Fatal uremic leontiasis ossea in long-lasting uncontrolled hyperparathyroidism: a case report

BACKGROUND

Leontiasis ossea is a rare medical condition, with characteristic overgrowth of the facial and cranial bones. Reports about this uremic complication are less frequently reported, probably due to better dialysis and better medical control of secondary hyperparathyroidism.

DESCRIPTION OF CASE

We report the case of a 36-year-old female patient who had been treated with chronic hemodialysis and who developed secondary hyperparathyroidism.

CONCLUSION

In noncompliant patients with uncontrolled secondary hyperparathyroidism uremic leontiasis may develop in which case the treatment is rarely successful or may even be contraindicated due to other comorbid conditions. Hippokratia 2015; 19 (3): 266-267.

Calcium-induced alteration of mitochondrial morphology and mitochondrial-endoplasmic reticulum contacts in rat brown adipocytes

Mitochondria are key organelles maintaining cellular bioenergetics and integrity, and their regulation of [Ca²⁺]_i homeostasis has been investigated in many cell types. We investigated the short-term Ca-SANDOZ^® treatment on brown adipocyte mitochondria, using imaging and molecular biology techniques. Two-month-old male Wistar rats were divided into two groups: Ca-SANDOZ^® drinking or tap water (control) drinking for three days. Alizarin Red S staining showed increased Ca²⁺ level in the brown adipocytes of treated rats, and potassium pyroantimonate staining localized electron-dense regions in the cytoplasm, mitochondria and around lipid droplets. Ca-SANDOZ^® decreased mitochondrial number, but increased their size and mitochondrial cristae volume. Transmission electron microscopy revealed numerous enlarged and fusioned-like mitochondria in the Ca-SANDOZ^® treated group compared to the control, and megamitochondria in some brown adipocytes. The Ca²⁺ diet affected mitochondrial fusion as mitofusin 1 (MFN1) and mitofusin 2 (MFN2) were increased, and mitochondrial fission as dynamin related protein 1 (DRP1) was decreased. Confocal microscopy showed a higher colocalization rate between functional mitochondria and endoplasmic reticulum (ER). The level of uncoupling protein-1 (UCP1) was elevated, which was confirmed by immunohistochemistry and Western blot analysis. These results suggest that Ca-SANDOZ^® stimulates mitochondrial fusion, increases mitochondrial-ER contacts and the thermogenic capacity of brown adipocytes.

New insights into male (in)fertility: the importance of NO

Infertility is a global problem that is on the rise, especially during the last decade. Currently, infertility affects approximately 10-15% of the population worldwide. The frequency and origin of different forms of infertility varies. It has been shown that reactive oxygen and nitrogen species (ROS and RNS) are involved in the aetiology of infertility, especially male infertility. Various strategies have been designed to remove or decrease the production of ROS and RNS in spermatozoa, in particular during in vitro fertilization. However, in recent years it has been shown that spermatozoa naturally produce a variety of ROS/RNS, including superoxide anion radical (O2 (⋅-)), hydrogen peroxide and NO. These reactive species, in particular NO, are essential in regulating sperm capacitation and the acrosome reaction, two processes that need to be acquired by sperm in order to achieve fertilization potential. In addition, it has recently been shown that mitochondrial function is positively correlated with human sperm fertilization potential and quality and that NO and NO precursors increase sperm motility by increasing energy production in mitochondria. We will review the new link between sperm NO-driven redox regulation and infertility herein. A special emphasis will be placed on the potential implementation of new redox-active substances that modulate the content of NO in spermatozoa to increase fertility and promote conception.

The effect of melatonin on body mass and behaviour of rats during an exposure to microwave radiation from mobile phone

BACKGROUND

Microwave radiation (MW) produced by wireless telecommunications and a number of electrical devices used in household or in healthcare institutions may cause various disorders in human organism. On the other hand, melatonin is a potent antioxidant, immunostimulator and neuromodulator. The aim of this research was to determine body mass and behaviour changes in rats after a chronic microwave exposure, as well as to determine the effects of melatonin on body mass and behaviour in irradiated rats.

METHODS

Wistar rats were divided into the four experimental groups: I group (control) - rats treated with 0,9 % saline, II group (Mel) - rats treated with melatonin (2 mg/kg), III group (MW) - rats exposed to MW radiation (4 h/day), IV group (MW+Mel) - rats, which were both exposed to MW radiation and received melatonin premedication (2 mg/kg).

RESULTS

A significant body mass reduction was noted in animals exposed to MW radiation when compared to controls after 20, 40 and 60 days (p<0.001). Furthermore, body weight was significantly increased (p<0.05) in irradiated rats, which received melatonin pretreatment (MW+Mel) in comparison to irradiated group (MW) after 20 days. Microwave radiation exposed animals showed an anxiety related behaviour (agitation, irritability) after 10 days of exposure. After the radiation source removal, changes in behaviour were less noticeable. Melatonin administration to irradiated rats caused a decrease in the stress induced behaviour.

CONCLUSION

Microwave radiation causes body mass decrease and anxiety related behaviour in rats, however melatonin causes a reverse of those effects on both body weight and behaviour of irradiated animals (Fig. 2, Ref. 32).

Endothelial cell apoptosis in brown adipose tissue of rats induced by hyperinsulinaemia: the possible role of TNF-α

The aim of the present study was to investigate whether hyperinsulinaemia, which frequently precedes insulin resistance syndrome (obesity, diabetes), induces apoptosis of endothelial cells (ECs) in brown adipose tissue (BAT) and causes BAT atrophy and also, to investigate the possible mechanisms underlying ECs death. In order to induce hyperinsuli-naemia, adult male rats of Wistar strain were treated with high dose of insulin (4 U/kg, intraperitonely) for one or three days. Examinations at ultrastructural level showed apoptotic changes of ECs, allowing us to point out that changes mainly but not exclusively, occur in nuclei. Besides different stages of condensation and alterations of the chromatin, nuclear fragmentation was also observed. Higher number of ECs apoptotic nuclei in the BAT of hyperinsulinaemic rats was also confirmed by propidium iodide staining. Immunohistochemical localization of tumor necrosis factor-alpha (TNF-α) revealed increased expression in ECs of BAT of hyperinsulinaemic animals, indicating its possible role in insulin-induced apoptotic changes. These results suggest that BAT atrophy in hyperinsulinaemia is a result of endothelial and adipocyte apoptosis combined, rather than any of functional components alone.

The role of nitric oxide in remodeling of capillary network in rat interscapular brown adipose tissue after long-term cold acclimation

Cold exposure has been shown to increase blood flow in interscapular brown adipose tissue (IBAT). The aim of the present study was to evaluate the role of the L-arginine-nitric oxide (*NO) pathway on IBAT capillary network remodeling and its possible correlation with superoxide anion radical (O2(*-)). In the rats that received L-arginine (2.25%) or NG-nitro-L-arginine methyl ester (L-NAME, 0.01%) as a drinking liquid and maintained at room (22+/-1 degrees C) or low (4+/-1 degrees C) temperature for 45 days, IBAT capillaries were analyzed by stereology and observed by light and electron microscopy. Additionally, endothelial *NO synthase (eNOS) expression, nitrotyrosine immunoreactivity and both copper zinc superoxide dismutase (CuZnSOD) enzyme activity and immunohistochemical localization were examined. Stereological analyses of IBAT show that the capillary volume density, as well as capillary-to-brown adipocytes ratio, are increased in cold. L-arginine treatment increases, while L-NAME decreases both parameters, compared to respective controls. Those changes were accompanied by capillary dilatation observed by light and electron microscopy. The activity of CuZnSOD is lower in control cold-acclimated rats, as well as in both L-arginine-treated groups, when compared to control animals acclimated to room temperature. L-NAME treatment attenuates the effects both of cold and L-arginine on CuZnSOD and increases immunopositivity for CuZnSOD in room temperature-acclimated rats. Our results show that *NO induces remodeling of the IBAT capillary network by angiogenesis, and presumably that interaction with O2(*-) has a role in that modulation. The increased eNOS expression accompanied by an increased nitrotyrosine immunoreaction observed in both L-arginine-treated groups compared to corresponding controls strengthens this hypothesis.