Electrically charged GTAM membranes stimulate osteogenesis in rabbit calvarial defects

Bone neogenesis was studied in membrane-protected defects in a rabbit calvaria defect model using neutral, negatively, and positively charged titanium-reinforced GTAM membranes. Two standardized circular 8 mm wide and 1 mm deep defects were created in the calvaria of 36 rabbits leaving the inner cortex intact. The defects were subsequently covered with dome-shaped Ti-reinforced GTAM membranes stabilized with a titanium screw allowing the edges of the membranes to be closely approximated to the bone surface. The animals were divided into 6 groups of 6 rabbits each and were sacrificed at 5 days (Group 1), 10 days (Group 2), 3 weeks (Group 3), 5 weeks (Group 4), 10 weeks (Group 5), and 20 weeks (Group 6). The distribution of the 72 membranes according to charge yielded 4 positively charged, 4 negatively charged and 4 neutral domes in each group. Histomorphometric analysis showed a more rapid and increased bone neogenesis with the negatively charged domes. A mean total area of 27.95% of newly-formed bone was observed in the negatively charged membrane sites at 10 days while negligible bone formation occurred with the neutral and positively charged domes at the same evaluation interval. Over time, negatively charged membranes supported more new-bone formation than neutral membranes while positively charged membranes showed the least new bone. This work demonstrates that negative electrical stimulation accelerates and maintains bone neogenesis. These results also suggest the potential applications of negatively charged GTAM membranes in clinical settings.     

Are vertical meridian effects due to audio-visual interference? A new confirmation with deaf subjects

Purpose. Specific increases of reaction times (RTs) were found in normal subjects, when endogenous spatial cues and targets were separated by the vertical visual meridian (VM) or by the vertical auditory (AM) meridian, when targets were either visual or auditory. The aim of this study was to assess if this effect could be attributed to longer RTs needed to shift activation between the hemispheres, or rather to different spatial maps underlying visual and auditory attention.

Method. We tested the VM effect in deaf subjects. If the shifting of activation from one hemisphere to the other causes the increase in RTs, then no differences between normal and sensory disabled people should take place, as the incoming perceptual information in the residual modality uses the same neural pathways while crossing the vertical meridian. Conversely, if the vertical meridian effects are related to the spatial representation systems underlying endogenous orienting mechanisms, then the lack of the auditory perceptual system in deaf people may have determined different organization processes in the brain circuits, strongly affecting the orienting mechanisms of spatial attention.

Results. Compared with a control group of hearing subjects, we found no evidence of the VM effect in deaf subjects.

Conclusions. This finding, jointly with those of a previous experiment which showed no AM effect on blind subjects (Olivetti Belardinelli & Santangelo 2005) supports the idea of different spatial maps underlying visual and auditory attention, and suggests that their co-existence may induce interference effects in space processing, giving rise to the anisotropic representation of visual and auditory spaces, observed in normal subjects.     

Pain evaluation and management: a survey of Italian radiotherapists

Goals The objective of this study was to assess the knowledge possessed and the attitudes held by Italian radiotherapists regarding evaluation and treatment of pain.Methods One hundred and twenty-six radiotherapists completed a 16-item questionnaire that was specifically designed to investigate three main topics: the attention paid to pain, the use of analgesics, and pain in children. Chi-square or Fishers exact text was employed to evaluate differences based on position (staff/resident), age (<35/>35 years old), availability of consultants in pain therapy and/or palliative care, colleagues with main interest in palliative care among their own staff, and region of residence (north/center/south of Italy).Results Overall percentage of correct answers was 76.6% (range 34.9–94.4%). Correct answers by groups of items were: attention paid to pain 77.3%, use of analgesics 81.5%, and pain in children 63.7%.Conclusion Results of the survey demonstrate that knowledge and attitudes of Italian radiotherapists towards the approach to and treatment of pain can be considered satisfactory.     

The palliative prognostic score and survival in patients with advanced solid tumors receiving chemotherapy

Purpose To evaluate the accuracy of the Palliative Prognostic Score (PaP score) in selecting metastatic gastrointestinal or nonsmall-cell lung cancer patients candidate to palliative chemotherapy. Materials and methods The PaP score was calculated in 173 patients with advanced, pretreated gastrointestinal or nonsmall-cell lung cancer before starting a further line of chemotherapy with palliative aim. Symptom distress score was calculated using the Edmonton Symptom Assessment System (ESAS) before every course of chemotherapy. Univariate analysis of survival was performed using the logrank test; multivariate analysis was performed using the Cox regression model. Symptom distress scores were compared using multivariate analysis of variance test for repeated measures, and overall symptom distress score was compared using analysis of variance test for repeated measures. Results Overall median survival was 26 weeks; in PaP score class A it was 32 weeks, and in class B 8 weeks (p < 0.0001). No patient was classified in class C. The two-class PaP score resulted in an independent prognostic factor (p = 0.022), as well as Karnofsky performance status (p = 0.002) and colorectal cancer (p = 0.017). A trend towards worsening of symptom distress was observed in the entire population and in class A. The high number of missed data did not permit an adequate analysis in class B. Conclusions The PaP score seems to discriminate patients who could benefit by palliative chemotherapy from those who could better benefit by supportive and palliative approach. However, the data are insufficient to validate the use of the PaP score in patients to be treated with palliative chemotherapy, and further trials should be planned to assess its ability to improve the quality of care in oncology and the appropriateness in the choice of palliative chemotherapy.     

Imaging signal transduction via arachidonic acid in the human brain during visual stimulation, by means of positron emission tomography

BACKGROUND: Arachidonic acid (AA, 20:4n-6), an important second messenger, is released from membrane phospholipid following receptor mediated activation of phospholipase A(2) (PLA(2)). This signaling process can be imaged in brain as a regional brain AA incorporation coefficient K*. HYPOTHESIS: K* will be increased in brain visual areas of subjects submitted to visual stimulation. SUBJECTS AND METHODS: Regional values of K* were measured with positron emission tomography (PET), following the intravenous injection of [1-(11)C]AA, in 16 healthy volunteers subjected to visual stimulation at flash frequencies 2.9 Hz (8 subjects) or 7.8 Hz (8 subjects), compared with the dark (0 Hz) condition. Regional cerebral blood flow (rCBF) was measured with intravenous [(15)O]water under comparable conditions. RESULTS: During flash stimulation at 2.9 Hz or 7.8 Hz vs. 0 Hz, K* was increased significantly by 2.3-8.9% in Brodmann areas 17, 18 and 19, and in additional frontal, parietal and temporal cortical regions. rCBF was increased significantly by 3.1-22%, often in comparable regions. Increments at 7.8 Hz often exceeded those at 2.9 Hz for both K* and rCBF. Decrements in both parameters also were produced, particularly in frontal brain regions. CONCLUSIONS: AA plays a role in signaling processes provoked by visual stimulation, since visual stimulation at flash frequencies of 2.9 and 7.8 Hz compared to 0 Hz modifies both K* for AA and rCBF in visual and related areas of the human brain. The two-stimulus condition paradigm of this study might be used with PET to image effects of other functional activations and of drugs on brain signaling via AA.     

Modifications in SENV DNA detection and/or SENV subtype determination over a prospective follow-up in a cohort of HIV-positive patients: is this a moving target?

SEN virus (SENV) is a new family of single-stranded DNA viruses with eight different strains, A-H. The modifications in SENV DNA detection and subtype distribution were studied over a long-term follow-up (48 +/- 32.5 months) in 52 HIV-infected patients. 46% of the patients in the first sample and 34.6% in the second sample were found to have detectable SENV viremia. While the most prevalent variant in the first sample was found to be genotype A (83.3%), the second sample revealed a broader subtype diversification. Several epidemiological and clinical variables were tested in univariate model for clearance of detectable SENV viremia, but none of them reached statistical significance. In conclusion, a high degree of instability of both SENV DNA detection and subtype distribution in a cohort of HIV-infected patients was suggested, which may have important implications for further studies on both SENV epidemiology and its clinical impact.