Time-domain analysis of scrotal thermoregulatory impairment in varicocele.

Varicocele is a common male disease defined as the pathological dilatation of the pampiniform plexus and scrotal veins with venous blood reflux. Varicocele usually impairs the scrotal thermoregulation via a hemodynamic alteration, thus inducing an increase in cutaneous temperature. The investigation of altered scrotal thermoregulation by means of thermal infrared imaging has been proved to be useful in the study of the functional thermal impairment. In this study, we use the Control System Theory to analyze the time-domain dynamics of the scrotal thermoregulation in response to a mild cold challenge. Four standard time-domain dynamic parameters of a prototype second order control system (Delay Time, Rise Time, closed poles locations, steady state error) and the static basal temperatures were directly estimated from thermal recovery curves. Thermal infrared imaging data from 31 healthy controls (HCS) and 95 varicocele patients were processed. True-positive predictions, by comparison with standard echo color Doppler findings, higher than 87% were achieved into the proper classification of the disease stage. The proposed approach could help to understand at which specific level the presence of the disease impacts the scrotal thermoregulation, which is also involved into normal spermatogenesis process.

Non-invasive in vivo detection of peripheral limb ischemia improvement in the rat after adipose tissue-derived stromal cell transplantation.

BACKGROUND: Adipose tissue-derived stromal cells (ADSCs) might help repair ischemic cardiovascular tissue. Their in vivo effects on the bioenergetics and microcirculation of ischemic muscle through a variety of non-invasive techniques was examined. METHODS AND RESULTS: Unilateral hindlimb ischemia was induced in 42 rats. One day after femoral artery ligation, 6 rats per group were randomly injected with intramuscularly allogeneic ADSCs (10(6)-10(7)-10(8) cells/ml), conditioned media from ADSC cultures (conditioned media [CM], control), saline (control), allogeneic fibroblasts (10(7) cells/ml, control) or a non-conditioned medium (control). Rats underwent magnetic resonance angiography (MRA), short-time inversion recovery (STIR) edema-weighed imaging, proton MR spectroscopy ((1)H-MRS), thermal infrared imaging (IRI), immunoblotting and immunofluorescence analysis on both hindlimbs for 4 weeks. MRA and STIR documented arterial occlusion and ischemia, respectively. Muscle (1)H-MRS and IRI showed reductions of total creatine (tCr)/water and skin temperature in occluded hind limbs, respectively. At 4 weeks, the ADSC and CM groups had greater recovery of skin temperature and tCr/water in ischemic limbs compared with controls (P<0.01), with increased expression of α-sarcomeric actinin and vascular growth factors, such as hepatocyte growth factor (HGF), increased vessel density (capillaries, arterioles and venules) and less type III collagen. CONCLUSIONS: Allogeneic ADSCs improve ischemic muscle metabolism, increase neovasculogenesis and decrease fibrosis, largely through a paracrine mechanism. (1)H-MRS and IRI are useful tools to monitor attempts at salvaging the ischemic tissues with cell-derived novel therapies.

A-magnetic optic-mechanical device to quantify finger kinematics for fMRI studies of bimanual coordination.

Several fMRI studies have been performed to detect the neural correlates of stable bimanual coordination patterns in humans. Only few of those studies were accompanied by the on-line recording of the relative phase of fingers or hands, but none with high space and time resolutions. Conversely, the high-resolution recording of fingers' kinematics during fMRI would permit the quantification of the instantaneous fingers' positions, from which the instant at which transitions between different bimanual coordination patterns occur might be detected. This information could then be used to analyze fMRI data and detect the neural correlates of pattern transitions. We describe an a-magnetic optic-mechanical device (AMOMeD) able to monitor the fingers' positions during fMRI studies on bimanual coordination with 2 mm space resolution and 1 ms time resolution. From the instantaneous fingers' positions (recorded with an optical fiber system and a dedicated acquisition system), the oscillation amplitude, frequency, velocity and relative phase of fingers' are calculated. The signal from the fMRI trigger can be acquired simultaneously to synchronize the behavioral outcomes with the fMRI analysis. The results of our study show that this device does not affect fMRI signals, and that fMRI data can be processed using the simultaneous behavioral information to detect the brain areas activated during the transitions between different bimanual coordination patterns.