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R Cristiani

Publications and source records attributed to R Cristiani.

16 recordsLinked to original sources
PubMed2004

Time-course of electromagnetic field effects on human performance and tympanic temperature.

The study aimed to investigate the time-course of electromagnetic field (EMF)-induced effects on human cognitive and behavioral performance and on tympanic temperature. Subjects were randomly assigned to two groups, exposed to a 902.40 MHz EMF before the testing session, or to the same signal during the data collecting session. Following a double-blind paradigm, subjects were tested on four performance tasks: an acoustic simple-reaction time task, a visual search task, an arithmetic descending subtraction task and an acoustic choice-reaction time task. Moreover, tympanic temperature was collected five times during each session. Results indicated an improvement of both simple- and choice-reaction times and an increase of local temperature on the exposed region under the active exposure. There was a clear time-course of the reaction time and temperature data, indicating that performance and physiological measures need a minimum of 25 min of EMF exposure to show appreciable changes.

Adult↗
PubMed2001

Antero-posterior EEG changes during the wakefulness-sleep transition.

OBJECTIVES: To investigate the brain topography of the human sleep EEG along the antero-posterior axis during the wakefulness-sleep transition, by means of both a single Hz analysis and a grouped-frequency analysis of EEG changes. METHODS: EEG power values were calculated across a 1-28 Hz frequency range in a 1 Hz resolution during the wakefulness-sleep transition of 7 normal subjects. Topographical changes were assessed from C3-A2, C4-A1, Fpz-A1, Fz-A1, Cz-A1, Pz-A1, Oz-A1 recordings, after averaging individual time series, aligned with respect to the onset of stage 2. RESULTS: The single Hz analysis showed that before sleep onset (SO), the <7 Hz slow frequencies were more prominent at the more anterior scalp locations; this anterior prominence was counterbalanced by a reciprocal prevalence across the >8 Hz frequencies of EEG activity from the occipital areas; while the >13 Hz fast frequencies were not characterized by significant antero-posterior differences. After SO, more EEG power was found in the range of slow frequencies at the centro-frontal scalp locations and a second peak of EEG activity was also revealed within the range of the sigma frequency, higher at the centro-parietal scalp locations. No consistent topographical changes were observed within the range of faster EEG frequencies. Grouped-frequency analysis confirmed these results, also pointing to different changes in the alpha frequency as a function of the SO point. CONCLUSIONS: The results suggest that: (a) the alpha rhythm spreads anteriorly as the transition progresses; (b) several anterior areas first synchronize EEG activity; (c) the functional meaning of the EEG bands during the SO period should be partially revised with regard at least to alpha rhythm; (d) SO coincides with the start of stage 2.

Adult↗
PubMed2000

Expression of somatostatin subtype 1 receptor in the rabbit retina.

PURPOSE: To detect mRNAs for somatostatin (somatotropin release-inhibiting factor [SRIF]) receptor subtypes 1 to 5 (sst(1) through sst(5)) in rabbit retinas by reverse transcription-polymerase chain reaction (RT-PCR) and to investigate the distribution of sst(1) by single- and double-label immunocytochemistry. METHODS: Semiquantitative RT-PCR using sst-specific primers from mouse sequences was performed. sst(1) was localized using a polyclonal antiserum directed to human sst(1) in cryostat sections of retinas from either normal or optic nerve-transected animals. Immunolabeled cell sizes and densities were measured in wholemounted retinas using computer-assisted image analysis. Double-label immunofluorescence was performed using the sst(1) antiserum in conjunction with monoclonal antibodies directed to SRIF, tyrosine hydroxylase (TH), parvalbumin (PV), or gamma-aminobutyric acid (GABA). RESULTS: With RT-PCR it was found that all five sst mRNAs were expressed in the rabbit retina, with highest levels of sst(1) mRNA. sst(1) immunolabeling was localized to amacrine cells in the proximal inner nuclear layer (INL) of all retinal regions and to displaced amacrine cells in the ganglion cell layer (GCL) of the ventral retina. Some large sst(1)-immunoreactive (IR) somata were also present in the GCL. They were not observed after optic nerve transection. Double-label immunofluorescence showed sst(1) expression by all TH-IR amacrine cells and by other amacrine cells that were neither PV-IR nor GABA-IR. In addition, sst(1) was expressed by all SRIF-containing displaced amacrine cells. CONCLUSIONS: All five sst mRNAs are expressed in the rabbit retina. The localization of sst(1) suggests that it may mediate SRIF actions onto amacrine (including dopaminergic) and sparse ganglion cells. sst(1) expression in SRIF-IR cells suggests that this receptor may also act as an autoreceptor.

Animals↗
PubMed1985

Role of delayed cutaneous hypersensitivity reaction in classifying patients with bronchial carcinoma.

Cell-mediated immune response was evaluated in 150 patients with histologically confirmed bronchopulmonary carcinoma using bacterial and fungal recall antigens injected intradermally (PPD, candida, trichophyton). In the study group negative skin test reaction was found in 51 of 150 patients (34.0%), whereas in the control population it was found in 5 of 33 cases (15.1%) (p less than 0.05). Histologic cell type and stage of disease were defined for each patient. It was possible to calculate the growth rate of the primary tumor only in 68 of 150 patients, and it was recorded as doubling time. Evaluation of the skin test reaction in each prognostic subgroup showed no statistically significant differences. The only statistically significant differences were found when each prognostic subgroup was compared with the control population according to the frequency of a negative response to the skin test, particularly in stage III M1 (p less than 0.05) and stage III M0 (p less than 0.02). The delayed cutaneous hypersensitivity studied with recall antigen stimulation was mainly correlated with the stage of disease, and it should not be considered as an independent prognostic factor.

Candida↗
PubMed1983

A new multiparametric classification in lung cancer patients - S.M.I.G.

The classification of bronchogenic carcinoma as a function of the prognosis is still an open field. The evaluation of stage, by use of the TNM system, and histologic cell type is not sufficient to guarantee a correct prognosis. The growth rate of the neoplasm is another important parameter. We propose a classification that takes into account the stage (S), histologic cell type (M), immune status (I) and the growth rate of the primary tumor (G): S.M.I.G. We studied 90 lung cancer patients according to the S.M.I.G. classification and we observed that their prognoses were directly correlated with their S.M.I.G. scores (the higher the score, the higher the 10-month mortality rate). The mortality rates within the first 10 months of follow-up were respectively 0%, 0%, 36.36%, 68%, 90.9% for the 5 groups obtained by S.M.I.G. The difference is statistically significant (P less than 0.0075) and there is a linear correlation between the mortality rate and the score assigned to each group (R = 0.943; P less than 0.05). The S.M.I.G. classification can predict the prognosis more efficiently than the usual classification (TNM) and histological cell type.

Adenocarcinoma↗
PubMedDate not supplied

[Surgery of epithelioma in the outer canthus].

We review the tumors localized in the orbito-palpebral region. Their prevalence varies between 2.5 and 16.8%. Skin epitheliomas are more frequently seen. We discuss the surgical techniques for the repair and reconstruction of the orbital region.

Carcinoma↗