Combined effect of heterogeneous target dose and heterogeneous radiosensitivity on tumor control probability for different fractionation regimens.

Purpose: To evaluate the combined effect of heterogeneous target dose and heterogeneous radiosensitivity on tumor control probability (TCP) for different number of fractions (N).

Methods: The linear-quadratic (LQ) model is employed to study dependence of TCP on N under the condition of fixed nominal biologically effective dose (BED).

Results: Formula for the optimum target dose which maximizes TCP under the condition BED=const is analytically derived.

Effect of heterogeneous target dose and radiosensitivity on BED and TCP for different treatment regimens.

To evaluate how heterogeneity of the target dose and heterogeneity of intra-tumor radiosensitivity affect biologically effective dose (BED) and tumor control probability (TCP) depending on the number of fractions (Nf).The dependences of TCP and BED in the planning target volume onNfare studied using the linear-quadratic model. In the considered case, the nominal biologically effective dose(BEDnom)is fixed and the variances of the target dose (σD) and radiosensitivity (σα) are assumed to be small.

Impact of target dose inhomogeneity on BED and EUD in lung SBRT.

Purpose: To evaluate the effect of dose heterogeneity in the treatment target on biologically effective dose (BED) for frequently used hypofractionation regimens in stereotactic body radiation therapy (SBRT).

Methods: In the case of non-uniform target dose, BED in the planning target volume (PTV) is determined by using the linear-quadratic model. An expression for BED is obtained for an arbitrary dose distribution in the PTV in the case of small variance of the target dose.

A Soft Wearable and Fully-Textile Piezoresistive Sensor for Plantar Pressure Capturing.

The trends of wearable health monitoring systems have led to growing demands for gait-capturing devices. However, comfortability and durability under repeated stress are still challenging to achieve in existing sensor-enabled footwear. Herein, a flexible textile piezoresistive sensor (TPRS) consisting of a reduced graphene oxide (rGO)-cotton) fabric electrode and an Ag fabric circuit electrode is proposed.

Effect of reoxygenation on hypofractionated radiotherapy of prostate cancer.

Purpose: To assess the role of reoxygenation of hypoxic tumor cells in hypofractionated radiotherapy of prostate cancer.

Methods: The considered radiobiological model is based on the assumption of two populations (compartments) of cells: oxygenated (aerobic) cells and hypoxic cells. After each fraction of radiation, some of the hypoxic cells reoxygenate while a fraction of initially aerobic cells becomes hypoxic.

Signal Quality and Electrode-Skin Impedance Evaluation in the Context of Wearable Electroencephalographic Systems.

Recent advancement in technology has brought about increase in the application areas of wearable electroencephalographic devices. In that, new types of electrodes take place, and particular attention is needed to ensure the required quality of obtained signals. In this study, we evaluate electrode-skin impedance and signal quality for several kinds of electrodes when used in conditions typical for wearable devices.

On the usefulness of portal monitor unit subtraction in radiation therapy.

In order to avoid additional dose to patients caused by portal imaging with megavoltage x-rays, portal monitor units (MUs) are frequently subtracted from the actual treatment MUs. This study examines the usefulness of portal MU subtraction in radiation therapy. For 11 prostate cancer patients treated with 23 MV photons, dose to prostate due to portal filming with 6 MV photons was determined.

Aggressive and violent behavior in a population of psychiatric inpatients.

The aim of this observational study was to assess the rates of aggressive and violent behavior in patients admitted to an Italian emergency psychiatric unit and to explore possible risk factors for patient violence. In a population of 313 consecutive patients, we considered aggressive or violent behavior, rated according to a hierarchy from no aggressive behavior to serious physical violence. The results confirm that young age, psychotic symptoms, excitement, akathisia, and diagnosis of personality disorder are risk factors for violent behavior.

Localization of the prostatic apex for radiotherapy planning: a comparison of two techniques.

Autopsy and pathology studies have shown that the caudal portion of the prostate gland harbors tumour in 64-75% of specimens examined. Accurate localization of the prostatic apex may be important in improving local control with external beam radiation therapy. We compared the location of the apex obtained with CT based treatment planning versus localization using retrograde urethrography in 32 consecutive patients.

Differentiating between T1 and T2* changes caused by gadopentetate dimeglumine in the kidney by using a double-echo dynamic MR imaging sequence.

Dynamic MR images of the passage of gadopentetate dimeglumine through the kidneys of normal rats are obtained using a dual gradient-echo sequence. The amplitudes of gradient echoes are defined by local T1 and T2* values in the tissue. The ratio of these amplitudes, primarily defined by local T2*, can be used to differentiate between T1 and T2* effects.

Changes in T2*-weighted images during hyperoxia differentiate tumors from normal tissue.

Experiments were performed to determine whether changes in T2*-weighted MR images during and after hyperoxia differentiate tumors from normal tissue. Mammary adenocarcinomas implanted in the right hind limbs of rats were studied. Gradient echo images were obtained at 2 Tesla with an evolution time of 20 ms and a recycle time of 1 s.

Neuroleptic malignant syndrome and catatonia. A report of three cases.

In a series of 1007 consecutively admitted patients, 3 cases of neuroleptic malignant syndrome (NMS) were identified (0.3%). All three patients were affected by mood disorders with congruent psychotic features, had shown catatonia just before the onset of NMS, and had been treated with low neuroleptic doses.

Magnetic resonance imaging of leiomyomata uteri: assessing therapy with the gonadotropin-releasing hormone agonist leuprolide.

Two cases are reported in which MRI was used to monitor the preoperative response of leiomyomata uteri to gonadotropin releasing hormone agonist therapy. The uterus was measured in the cephalocaudad, anterior-posterior, and transverse planes by MRI images. All uterine dimensions decreased in size after leuprolide therapy.