Is there a clinical future for spermatogonial stem cells?

Like every other adult stem cell in the human body, spermatogonial stem cells (SSCs) have the capacity to either renew themselves or to start the differentiation process, namely, spermatogenesis. Due to the continuation of the stem cell population in the testis, several possible options for preservation and re-establishment of the reproductive potential exist. Currently, spermatogonial stem cell transplantation (SSCT) is considered the most promising tool for fertility restoration in young cancer patients.

Multicenter evaluation of a rapid electrochemiluminescent adrenocorticotropic hormone (ACTH) immunoassay.

Background: Measuring plasma adrenocorticotropic hormone (ACTH) is a key step in the differential diagnosis of hypothalamic-pituitary-adrenal disorders.

Methods: The recently developed electrochemiluminescence Elecsys ACTH immunoassay (Roche Diagnostics, Mannheim, Germany) was evaluated at six clinical laboratories on the Modular E170 and/or the Elecsys 2010 (Roche Diagnostics) immunoanalysers.

Results: The within-run and between-run imprecision was View Article and Find Full Text PDF

Setup accuracy of stereoscopic X-ray positioning with automated correction for rotational errors in patients treated with conformal arc radiotherapy for prostate cancer.

We evaluated setup accuracy of NovalisBody stereoscopic X-ray positioning with automated correction for rotational errors with the Robotics Tilt Module in patients treated with conformal arc radiotherapy for prostate cancer. The correction of rotational errors was shown to reduce random and systematic errors in all directions. (NovalisBody and Robotics Tilt Module are products of BrainLAB A.

Congenital spherocytosis with hereditary hemochromatosis without pathogenic mutations in the HFE gene.

We report a case of an 80-year-old woman with congenital spherocytosis who presented with massive iron overload. Iatrogenic iron overload could be ruled out. Familial history was suggestive of hereditary hemochromatosis; however, molecular genetic testing for the most common HFE mutations remained negative.

Association between leisure time physical activity and markers of chronic inflammation related to coronary heart disease.

Background: Some markers of chronic inflammation have been recognized as predictors of cardiovascular risk in apparently healthy subjects and in patients with coronary heart disease (CHD). High sensitivity C-reactive protein (CRP) appears to be the most useful marker in clinical settings. Several studies reported associations between inflammatory markers and other cardiovascular risk factors, such as age, obesity, cholesterol levels, the presence of diabetes mellitus, physical activity, social level and smoking habits.

Comparison of 180 degrees and 360 degrees data acquisition for determination of left ventricular function from gated myocardial perfusion tomography and gated blood pool tomography.

The purpose of this study was to address the issue of 180 degrees versus 360 degrees data collection for left ventricular ejection fraction (LVEF) and left ventricular volume measurements using gated myocardial perfusion tomography (gMPT) and gated blood pool tomography (gBPT). Thirty patients with known coronary artery disease were injected in a random sequence with 925 MBq of technetium-99m tetrofosmin and, within 2 days, with 740 MBq of (99m)Tc-labelled human serum albumin. gMPT and gBPT were acquired using 360 degrees data collection and reconstructed by filtered backprojection using all the acquired projection images and separately using only projection images acquired from 45 degrees LPO to 45 degrees RAO.

Considerations on treatment efficiency of different conformal radiation therapy techniques for prostate cancer.

Background And Purpose: To evaluate the treatment efficiency of different conformal radiation therapy techniques in prostate cancer.

Materials And Methods: Three major classes of intensity-modulated radiation therapy (IMRT) delivery as well as a conformal rotation technique have been evaluated: sequential tomotherapy, dynamic multileaf collimation (DMLC) with conventional MLC, DMLC with miniMLC and dynamic field shaping arc. Treatment planning for the IMRT techniques has been performed with inverse planning.

Gated myocardial perfusion tomography versus gated blood pool tomography for the calculation of left ventricular volumes and ejection fraction.

Left ventricular (LV) volume, and not only ejection fraction (EF), is a crucial parameter for assessing the severity of cardiac disease and determining the patient's prognosis. The purpose of this study was to compare LV volumes and EF computed automatically from gated blood pool tomography (gBPT), using QUBE, and from gated myocardial perfusion tomography (gMPT), using QGS, in the same patients with a known history of myocardial infarction. The effects of the extent and severity of the myocardial perfusion defects were investigated.

Reconstruction of gated myocardial perfusion SPET incorporating temporal information during iterative reconstruction.

Reconstruction of gated single-photon emission tomography (gSPET) is intrinsically a four-dimensional (4D) problem. In practice, the time frames are reconstructed independently as a sequence of frame-by-frame reconstructions. This approach is not optimal since the strong signal correlations among the individual time frames are not exploited.

Definition of gross tumor volume in lung cancer: inter-observer variability.

Background And Purpose: To determine the inter-observer variation in gross tumor volume (GTV) definition in lung cancer, and its clinical relevance.

Materials And Methods: Five clinicians involved in lung cancer were asked to define GTV on the planning CT scan of eight patients. Resulting GTVs were compared on the base of geometric volume, dimensions and extensions.

Left ventricular ejection fraction and volumes from gated blood pool tomography: comparison between two automatic algorithms that work in three-dimensional space.

Background: Two different algorithms, which are fast and automatic and which operate in 3-dimensional space, were compared in the same group of patients to compute left ventricular ejection fraction (LVEF) and volumes from gated blood pool tomography. One method, developed at Cedars-Sinai Medical Center (CS), was dependent on surface detection, whereas the other method, developed at the Free University of Brussels (UB), used image segmentation.

Methods And Results: Gated blood pool tomograms were acquired in 92 consecutive patients after injection of 740 MBq of technetium 99m-labeled human serum albumin.

Interest of the ordered subsets expectation maximization (OS-EM) algorithm in pinhole single-photon emission tomography reconstruction: a phantom study.

Pinhole single-photon emission tomography (SPET) has been proposed to improve the trade-off between sensitivity and resolution for small organs located in close proximity to the pinhole aperture. This technique is hampered by artefacts in the non-central slices. These artefacts are caused by truncation and by the fact that the pinhole SPET data collected in a circular orbit do not contain sufficient information for exact reconstruction.

Effect of beta-blockade on low-dose dobutamine-induced changes in left ventricular function in healthy volunteers: assessment by gated SPET myocardial perfusion scintigraphy.

Viability studies are often performed in patients receiving beta-blocking agents. However, the intake of beta-blocking agents could influence the identification of viable myocardium when low-dose dobutamine is used to demonstrate inotropic reserve. The aim of this study was to quantify the effect of beta-blockade on global and regional left ventricular function in healthy volunteers using low-dose dobutamine gated single-photon emission tomographic (SPET) myocardial perfusion scintigraphy.

Low-dose dobutamine gated single-photon emission tomography: comparison with stress echocardiography.

Perfusion scintigraphy provides important information regarding the presence of viable tissue after myocardial infarction. Defects of moderate severity, however, may represent viable myocardium, necrotic tissue or a mixture of both. In this study the presence or absence of inotropic response in the infarcted area was assessed by low-dose dobutamine tetrofosmin gated single-photon emission tomography (LDD gated SPET).

Risk assessment of radiation-induced malignancies based on whole-body equivalent dose estimates for IMRT treatment in the head and neck region.

Background And Purpose: Intensity modulated radiation therapy (IMRT) has been introduced in our department for treatment of the head and neck region with the intention of reducing complications without compromising treatment outcome. However, these new treatment modalities inevitably require a substantial increase in monitor units per target dose yielding an increased risk of secondary malignancies induced by the treatment. This study aims at assessing the increased risk by means of in vivo measurements of the whole-body equivalent dose of both the conventional and the IMRT treatment techniques for head and neck lesions.

Effects of low-dose dobutamine on left ventricular function in normal subjects as assessed by gated single-photon emission tomography myocardial perfusion studies.

Electrocardiography gated single-photon emission tomography (gated SPET) allows the assessment of regional perfusion and function simultaneously and in full spatial congruency. In this study changes in global and regional left ventricular function in response to dobutamine infusion were assessed in ten healthy volunteers using sequential gated SPET myocardial perfusion acquisitions. Four consecutive gated SPET images were recorded 60 min after injection of 925 MBq technetium-99m tetrofosmin on a three-head camera equipped with focussing collimators.

Gated SPET myocardial perfusion acquisition within 5 minutes using focussing collimators and a three-head gamma camera.

Short acquisition protocols for gated single-photon emission tomography (SPET) myocardial perfusion imaging are desirable for sequential imaging to evaluate the myocardial response during pharmacological intervention. In this study a less than 5 min gated SPET acquisition protocol is proposed. Perfusion characteristics (defect severity) and left ventricular ejection fraction (LVEF), end-diastolic and end-systolic volumes (EDV, ESV), wall motion (WM) and wall thickening (WT) were calculated, checked for reproducibility and compared with data obtained using a standard gated SPET acquisition protocol.

Cardiofocal collimators for gated single-photon emission tomographic myocardial perfusion imaging.

Cardiofocal collimators (CFCs) are more sensitive than parallel-hole collimators (PHCs) of the same resolution because the rays converge in the centre of the field of view. After reconstruction a useful field of view with a 10 cm radius in which both sensitivity and resolution are homogeneous is obtained. In this article the feasibility and accuracy of gated single-photon emission tomographic (gated SPET) myocardial perfusion imaging using a triple-head camera equipped with CFC, is evaluated.

Left ventricular ejection fraction and volumes from gated single photon emission tomographic myocardial perfusion images: comparison between two algorithms working in three-dimensional space.

Objective: Two different algorithms operating in three-dimensional space, one dependent on surface detection developed at Cedars-Sinai Medical Center (CS) and another dependent on statistical parameters and developed at Stanford University Medical School (SU), were compared in the same patients to assess the left ventricular volumes and the left ventricular ejection fractions (LVEFs) from gated single-photon emission tomography (SPECT) myocardial perfusion images.

Methods: Perfusion SPECT images gated in eight time bins were recorded in 40 patients with coronary artery disease 60 minutes after the injection of 925 MBq 99mTc-labeled tetrofosmin at rest. The LVEF values were validated against planar gated 99mTc-labeled blood pool studies (ERNA).

Sigma-receptor imaging by means of I123-IDAB scintigraphy: clinical application in melanoma and non-small cell lung cancer.

Scintigraphy with 1123-N-(2-Diethyl aminoethyl) 4-Iodobenzamide (I123-IDAB), a radiolabeled benzamide, has recently been introduced to visualize sigma receptors in vivo. In this study we evaluated the potential clinical applicability of I123-IDAB scintigraphy in patients with melanoma and in patients with non-small cell lung carcinoma (NSCLC); tumors in which sigma receptors are expressed. Twenty-six patients with a history of malignant melanoma and 8 patients with proven NSCLC were studied.

Exact and approximate rebinning algorithms for 3-D PET data.

This paper presents two new rebinning algorithms for the reconstruction of three-dimensional (3-D) positron emission tomography (PET) data. A rebinning algorithm is one that first sorts the 3-D data into an ordinary two-dimensional (2-D) data set containing one sinogram for each transaxial slice to be reconstructed; the 3-D image is then recovered by applying to each slice a 2-D reconstruction method such as filtered-backprojection. This approach allows a significant speedup of 3-D reconstruction, which is particularly useful for applications involving dynamic acquisitions or whole-body imaging.

Left ventricular ejection fraction from gated SPET myocardial perfusion studies: a method based on the radial distribution of count rate density across the myocardial wall.

Left ventricular ejection fraction (LVEF) can be derived from gated single-photon emission tomographic (SPET) myocardial perfusion studies using either manual or edge detection techniques. In the presence of severe perfusion defects, however, difficulties may be encountered. In this article a method based on the assumption that the average position of the myocardial wall can be localized by means of statistical analysis of the distribution count density, and not on edge detection, is used to measure LVEF.

Early electrocardiographic signs in acute massive pulmonary embolism.

As a result of the increasing accuracy in diagnosing acute pulmonary embolism by isotopic ventilation-perfusion scintigraphy and pulmonary arterial angiography, the electrocardiographic changes associated with acute cor pulmonale are being abandoned as a diagnostic tool for this life-threatening disease. Nevertheless, certain electrocardiographic findings can raise the suspicion of pulmonary embolism. In our view the electrocardiogram does have some merits in the emergency work-up of a patient with a high suspicion of pulmonary embolism.

A rare case of diplopia: medial inferior pontine syndrome or Foville's syndrome.

A case of medial inferior pontine syndrome or Foville's syndrome is described. The patient presented to the emergency department with an acute history of slurred speech, vertigo and diplopia as major complaints. He also mentioned the appearance of weakness and numbness in his left leg.

Different clinical manifestations of meningococcaemia: three patient reports.

Neisseria meningitidis, a ubiquitous Gram-negative diplococcus, is responsible for a spectrum of clinical manifestations. This is illustrated by the history of three patients recently admitted to our hospital. Because of the possibly rapid and dramatic evolution, awareness for meningococcal diseases remains obligatory.