Application of Intravoxel Incoherent Motion (IVIM) Model for Differentiation Between Metastatic and Non-Metastatic Head and Neck Lymph Nodes.

BACKGROUND: Application of intravoxel incoherent motion (IVIM) model parameters, including: true diffusion (D), pseudodiffusion (D*), and perfusion fraction (Fp), for differentiation between metastatic and non-metastatic head and neck lymph nodes. MATERIAL/METHODS: Diffusion-weighted images/apparent diffusion coefficient (DWI/ADC) images of 86 lymph nodes from 31 cancer patients were analyzed. DWI images were obtained with a 1.5T MRI scanner (Magnetom Avanto); b=0,50, 150, 300, 500, 750, 1000, 1200 s/mm2. RESULTS: In the study group, there were 32 (37%) and 54 (67%) metastatic and non-metastatic lymph nodes, respectively. The mean values of D, D*, and Fp did not differ significantly between metastatic and non-metastatic lymph nodes. CONCLUSIONS: IVIM parameters are not useful for differentiation between metastatic and non-metastatic head and neck lymph nodes.

[Natural factors influencing sleep]. / Naturalne czynniki wplywajace na sen.

Sleep is a universal phenomenon of human and animal lives, although the importance of sleep for homeo-stasis is still unknown. Sleep disturbances influence many behavioral and physiologic processes, leading to health complications including death. On the other hand, sleep improvement can beneficially influence the course of healing of many disorders and can be a prognostic of health recovery. The factors influencing sleep have different biological and chemical origins. They are classical hormones, hypothalamic releasing and inhibitory hormones, neuropeptides, peptides and others as cytokines, prostaglandins, oleamid, adenosine, nitric oxide. These factors regulate most physiologic processes and are likely elements integrating sleep with physiology and physiology with sleep in health and disorders.

[Usefulness of FDG-PET for the diagnosis of brain tumors]. / Przydatnosc FDG-PET w diagnostyce guzów mózgu.

Although magnetic resonance imaging (MRI) and X-ray computed tomography (CT) are the two imaging modalities used conventionally for the morphological OUN imaging, there are many cases for positron emission tomography (PET) diagnostic. Basal radiopharmaceutic used in PET is a 18F-2-Fluoro-2-deoxy-D-glucose (18FDG). Use of PET imaging provides in vivo biochemical and physiological data and therefore can provide unique functional information about tumors compared to histological or anatomic neuroradiological methods. PET can provide information regarding tumor grading, delineation of tumors margins, differentiation of recurrent brain tumors from necrosis (golden standard), guidance for stereotactic biopsy, response to therapy and prognosis. New value in brain tumor imaging is combining two essential and complementary imaging modalities PET and multisection CT to create one integrated unit that allows both functional and anatomic imaging in a single study. This allows PET-CT for more accurate tumor localization and variability assessment changes impressions and increases diagnostic confidence. The first PET-CT centre in Poland is localised in Cancer Centre in Bydgoszcz. Scanning is performed on a dedicated Biograph (PET-CT) LSO scanner (SIMENS, Germany), and cyclotron RDS-111 (CTI, USA), FDG production laboratory (NUCLEAR INTERFACE, Germany, COMECER, Italy) and FDG quality control (RAYTES, Germany) are radiopharmaceutical production unit.

Effects of amphetamine on NK-related cytotoxicity in rats differing in locomotor reactivity and social position.

The effect of i.p. administration of 1mg/kg of amphetamine (AMPH) on natural killer cells cytotoxicity (NKCC) and number of large granular lymphocytes (LGL-NK) together with plasma corticosterone (CORT) level and WBC was evaluated in male Wistar rats differing in two behavioral features: locomotor reactivity to novelty (high, HR and low, LR responders) and social position (dominants, D and subordinates, S). In the majority of animals AMPH evoked (30 min after administration) an increase in NKCC and LGL (NK) number accompanied by lymphopenia, neutrocytosis, monocytosis, and an increase in CORT level. Changes in NKCC (LU20) showed substantial individual variability: in HR group approximately 513Delta%, p <0.01 (relative to the control); LR group approximately 56Delta%, p >.05; D group approximately 441Delta%, p >0.001; S group approximately 216Delta%, p >0.05; HR/D group approximately 643Delta%, p <.001; HR/S group approximately 414Delta%, p <.001; LR/D group approximately 191Delta%, p >.05; and LR/S group approximately -19Delta%, p .05. The increase in CORT level, lymphopenia, and neutrocytosis indicated a stress-like reaction to AMPH. No significant correlation between NKCC and CORT level was found. The results obtained indicate that AMPH can evoke an increase in NK-related cytotoxic activity quantitatively related to high behavioral reactivity to novelty and social dominance, however NKCC is not related to the AMPH-induced CORT changes.

Influence of small mechanical head injuries on peripheral blood natural killer cytotoxicity (NKCC) in rats.

Many neurophysiological experiments and some human's brain tissue stimulatory therapies require surgery intervention, which results in small mechanical skull and brain tissue injuries. Additionally, these procedures need some local or short general anaesthesia, which is not neutral for immune system action. Clinical data unambiguously shows that severe head and brain injuries and anaesthesia can suppress immunity. The aim of the present study was to investigate the influence of small mechanical skull and brain tissue injuries, accompanied by electrode fixation for experimental or therapeutic brain tissue stimulation, on peripheral blood natural killer cytotoxicity (NKCC) assessed in a 4h standard cytotoxic test. Additionally, we assessed a number of leukocytes, lymphocytes and large granular lymphocytes (LGL), which are NK cell subset and plasma corticosterone concentration. The results showed that small mechanical skull and meninges injuries or alone-administered Nembutal did not evoke any significant changes as those caused by electrode placement 4.2 mm below the skull surface. Deeper electrode fixation, 6.1; 7.6 and 8.4 mm below the skull surface, significantly increased NKCC (p < 0.05) and LGL number (p < 0.05) on the 3rd day after the electrode placement. Moreover, the results showed that some small brain tissue injuries could transiently influence the number of LGL and NKCC.

Effect on peripheral blood natural killer cytotoxic cell activity in rats after intraperitoneal implantation of double veloured polyester (Dacron) prosthesis.

INTRODUCTION: The aim of this study was to assess the changes affecting natural killer cytotoxic cell (NKCC) activity following intraperitoneal implantation of a double veloured polyester prosthesis in a rat model. MATERIAL/METHODS: Blood samples were taken by cardiac puncture 1 h before (base line) and 14, 28, 100 and 180 days post-implantation. Peripheral blood mononuclear cells were separated from heparinized blood by density centrifugation. A standard, 4 h (51)Cr-release assay against YAC-1 target cells at effector to target ratios of 12:1; 25:1 and 50:1 was performed and the number of total leukocytes, lymphocytes, granulocytes, monocytes, and large granular lymphocytes (LGLs), as well as serum corticosterone levels (radioimmunoassay method) were determined. RESULTS: Comparative analysis of the results obtained from animals with implants, baseline samples, and a control group (laparotomy only) revealed lower NKCC, LGL, leukocyte and lymphocyte counts and elevated plasma corticosterone levels in animals receiving the implant on the 14th day post-implantation. CONCLUSIONS: Our findings indicate that the polyester implant can transiently modulate immune system activities. Since NK cells are important in the control of viral infection and carcinogenesis in humans, it is possible that the stress generated by polyester prostheses can exacerbate the surgical stress and put patients at a higher risk for viral infection and/or metastases.