Development of a new sensor based on micro-electro-mechanical systems for objective in vivo measurement of the cutaneous temperature: application to foundations

BACKGROUND/AIMS: The purpose of this work was to develop a new sensor for objective in vivo measurement of the cutaneous temperature based on micro-electro-mechanical systems (MEMS), and to compare these performances with those of a classical thermocouple. Research on this new sensor was carried out to allow the quantification of the thermal properties of the made-up skin. METHODS: Sixteen female subjects divided into two different age groups (18-35 and >50 years old) were recruited for this study. Several zones of the face and forearms were made up at random with foundations containing or not a thermoregulator raw material. The quantity of foundation applied on the skin was standardized and measurements were carried out first before make-up, and then 10 s and 5 min after make-up. The new sensor and the thermocouple were used successively on each zone. The cutaneous temperature was expressed in degrees celsius. RESULTS/CONCLUSION: The two systems are similar in terms of repeatability and reproducibility, with some differences in sensibility. The data measured by the MEMS sensor appear lower than those measured by the thermocouple. After make-up, the MEMS sensor detects a progressive increase of the temperature in time whereas the thermocouple detects a decrease. We found the same evolution on the face but in a more attenuated way. These results tend to show that the devices do not measure the same phenomenon. The thermocouple appears more sensitive to the thermal response of the made-up surface whereas the MEMS sensor appears more sensitive to the heat transfers in the interface between the skin and make-up.     

192Ir low dose rate brachytherapy for boosting locally advanced prostate cancers after external beam radiotherapy: a phase II trial.

BACKGROUND AND PURPOSE: To evaluate on 201 locally advanced prostatic cancers prospectively treated in a phase II trial, the efficacy of a combination of external beam radiotherapy (39.6 Gy) and (192)Ir low dose rate brachytherapy (Bt) (40-45 Gy). PATIENTS AND METHODS: Sixty-four patients were included in the intermediate prognosis group with only one of the following adverse factors (PSA > 10 ng/ml, Gleason score > or = 7 or clinical stage > or =T2b) and 137 in the unfavourable group when at least two of these factors were present. RESULTS: The actuarial 4 years biochemical no evidence of disease is 82.8% for the entire population. It is, respectively, 97 and 76% in the intermediate and unfavourable prognosis groups (P < 0.0001). Grade > or =3 late urinary complications occurred in 13 patients (6.5%). Eight patients (4%) presented late grade 2 rectal complications but no grades 3-5 was observed. CONCLUSIONS: Even if an alpha/beta of 1.5-3 Gy theoretically favours the use of a high dose rate mode of irradiation, the early results presented here are as good as those reported for similar groups of patients with high dose rate treatments. Late toxicity is identical but our urinary toxicity is within the less favourable and rectal toxicity within the most favourable results. We can postulate that while inducing very high hyperdosage regions (V150) mainly focused on the peripheral zone, most of the Bt techniques consist of a more ablative treatment. Many of the radiobiological studies on Bt did not in fact take into account the heterogeneity of irradiation inside the CTV. This study highlights the need to explore pulsed dose rate therapies, permanent implant and new available radioisotopes such as (169)Ytterbium that will offer the safety of low and lower dose rates. The actual late toxicity of the different Bt techniques is not yet inexistent indeed.     

Examination of the effects of hemodynamic and pharmacologic interventions on coronary collateral flow in a patient during cardiac catheterization

The vasomotor response of native human collateral vessels to pharmacologic or hemodynamic vasodilatory stimuli is not well known. We describe a case where retrograde collateral flow velocity was measured both at baseline and following selected hemodynamic and pharmacologic interventions. This index case represents the first in a series of potential human physiologic studies designed to address questions pertaining to control of collateral blood supply in humans. © 1993 Wiley-Liss, Inc.     

Isolation impairs place preference conditioning to morphine but not aversive learning in mice

Morphine (8–100 mg/kg IP) induces place preference conditioning in mice. The effect of two different periods of isolation (15 and 30 days) was examined. Mice isolated for 15 days but not 30 days exhibited place preference conditioning to morphine (8 mg/kg). After 30 days of isolation morphine could not induce place preference conditioning with the following doses (8, 16, 64, 100 mg/kg). Social regrouping of male mice previously isolated for 30 days with naive female mice for 15 or 30 days resulted in a reappearance of the conditioned place preference to morphine (16 mg/kg). The specificity of this associative deficit was examined by testing learning in isolated compared to non-isolated mice in two distinct settings: escape learning in the Morris water maze and passive avoidance acquisition and retention. On the Morris water maze isolated mice did not differ from non-isolated mice regarding place learning, the probe trial or extinction. Isolated mice were unimpaired in passive avoidance acquisition and retention. It was concluded that the deficits in place preference conditioning were not the result of a global learning impairment in isolated mice. Received: 10 April 1996 /Final version: 20 September 1996