Gulliver's virtual travels: active embodiment in extreme body sizes for modulating our body representations

It is noted that the perceptual experience of body and space can be modulated by changing the action capabilities or by manipulating the perceived body dimensions through a multisensory stimulation. This study adds to pre-existing literature by investigating the alterations in bodily experience following embodiment to both enlarged and shrunked bodies, while participants actively navigated in a virtual environment. A normal-sized body served as a reference condition. After each embodied navigation, participants estimated the height and width of three different body parts. Results revealed that the embodiment over shrunked body induced a significant reduction in participants' body image, while no changes were reported after the embodiment over the enlarged body. Findings were discussed in terms of previous literature exploring the constraints implicated in the ownership over different bodies.

Composition and emission of VOC from biogas produced by illegally managed waste landfills in Giugliano (Campania, Italy) and potential impact on the local population

The composition in Volatile Organic Compounds (VOC) of the biogas produced by seven landfills of Giugliano (Naples, Campania, Italy) was determined and VOC emission rates assessed to verify if these compounds represent a potential threat to the population living nearby. VOC composition in the biogas could not be predicted, as heterogeneous waste was dumped from the late 1980s to the early 2000s and then underwent biological degradation. No data are available on the amount and composition of VOC in the biogas before the landfills closure as no operational biogas collection system was present. In this study, VOC composition was determined by gas chromatography-mass spectrometry (GC-MS), after collecting samples from collection pipes and from soil fractures in cover soil or capping. Individual VOC were quantified and data compared with those collected at two landfills in Latium, when they were still in operation. Relevant differences were observed, mainly due to waste aging, but no specific VOC revealing toxic waste dumping was found, although the concurrent presence of certain compounds suggested that dumping of industrial wastes might have occurred. The average VOC emission was assessed and a dispersion model was run to find out if the emitted plume could affect the health of population. The results suggested that fugitive emissions did not represent a serious danger, since the concentrations simulated at the neighboring cities were below the threshold limits for acute and chronic diseases. However, VOC plume could cause annoyance at night when the steady state conditions of the atmosphere enhance pollutants accumulation in the lower layers. In addition, some of the emitted VOC, such as alkylbenzenes and monoterpenes, can contribute to tropospheric ozone formation.

Abdominal aortic aneurysm in renal transplant recipients

BACKGROUND

Abdominal aortic aneurysms (AAA) requiring surgical management are encountered more frequently in renal transplant recipients, presenting an important technical problem during the repair. The aim of the present study was to analyze the epidemiology and natural evolution of AAA among renal allograft recipients.

METHODS

Three hundred ninety-four renal transplant recipients were periodically evaluated with abdominal aortic ultrasound tomography for AAA. The indication for surgery was a maximal diameter >5 cm. Renal function, graft, and patient survival were evaluated after a mean follow-up of 51 months.

RESULTS

Four AAA were detected in 394 renal transplant recipients, a prevalence of 1.01%. All of the AAA were found in male recipients of mean age 59.2 +/- 5.5 years and mean time posttransplantation of 82.7 +/- 77.3 months. The mean follow-up period between diagnosis and indication for surgery was 14.2 +/- 10.8 months. Two patients underwent open repair with aneurysmectomy and conventional tube graft positioning, and 2 patients refused surgical repair. To preserve renal graft function during the aortic cross-clamping phase, cold perfusion with 4 degrees C Ringer acetate and local hypothermia with sterile ice were used. Renal function did not change after the operation (preoperative serum creatinine levels were 1.2 and 1.3 mg/dL; postoperative 1.3 and 1.5 mg/dL respectively). The 2 patients who underwent surgery are alive with excellent graft functioning after a follow-up of 1.5 and 7 years, respectively. The 2 patients who refused surgical treatment are dead.

CONCLUSIONS

Yearly ultrasound screening for AAA must be recommended in renal transplant recipients as part of the routine posttransplantation follow-up. De novo AAA occurs in younger subject in the transplant population and shows a faster evolution.

[Recurrent biliary calculi]

The Authors report two cases of recurrent bile duct stones and discuss about the diagnosis and treatment of this infrequent disease. Although diagnostic and management procedures are similar to those commonly used in all types of biliary stones, therapeutical options may be different in relation to the different clinical pictures. The Authors strongly suggest that bilioenteric anastomosis and endoscopic sphincterotomy are the best procedures to assure a correct and definitive treatment of recurrent biliary stones. However, the adoption of different diagnostic and therapeutic approaches, rather than univocal schemes, is recommended.

[Rational and mini-invasive approach to the therapy in varicose syndrome: the C.H.I.V.A. treatment]

The principles of the C.H.I.V.A. (Ambulatory conservative and haemodynamic therapy of venous insufficiency) procedure are reported. According to the Authors a careful haemodynamic evaluation of the venous system strictly correlates to the clinical and functional results. In their experience, in fact, results showed no variceal recurrence and a very low rate of complications. Therefore, the C.H.I.V.A. procedure is recommended for most of the patients with lower limb varices.

Technetium-99m-MRP20, a potential brain perfusion agent: in vivo biodistribution and SPECT studies in normal male volunteers

The lipophilic neutral complex [99mTc][TcO(MRP20)] [MRP20 is (N-(2(1H pyrolylmethyl]N'-(4-pentene-3-one-2)ethane-1,2-diamine)] is known to cross the blood-brain barrier in non-primate animals. We report here its in vivo biodistribution, radiation dosimetry, and single-photon emission computed tomography (SPECT) characteristics in man. Following i.v. administration of 15-25 mCi of the tracer, the maximum uptake of activity in the brain peaked at 1 min p.i. Fifteen minutes p.i., the percentage retained in the brain was 5.2 +/- 1.6, which remained fairly constant over 24 hr. Blood clearance was relatively slow with an apparent affinity of the compound for the cellular fraction of the blood, however, soft-tissue and facial activity cleared at a rate four times faster than that of the brain. SPECT images obtained at 15 min, 1 hr, 3 hr, 7 hr, and 24 hr p.i. showed no redistribution of the tracer within the brain. The dosimetry is favorable for administration of 25-30 mCi of MRP20. Our results indicate that this compound is rapidly extracted and retained by the brain and may be used for SPECT imaging of regional blood flow.

Perineal colostomy and electrostimulated gracilis "neosphincter" after abdomino-perineal resection of the colon and anorectum: a surgical experience and follow-up study in 47 cases

A series of 47 patients undergoing abdomino-perineal resection of the distal colon and anorectum and construction of a continent perineal colostomy using electrostimulated gracilis muscle is described. External and implanted pulse generators have both been used. An analysis of complications and oncological data are reported. There was no operative mortality. The incidence of complications, divided into three classes, mild (62%), moderate (27%) and severe (11%), has not significantly altered the functional results, with the exception of early ischaemia of the colonic stump in two cases. During the first 22 cases, no preoperative oncological staging was performed. In the last 23 patients endorectal ultrasonography and CT scanning were carried out. Functional results were evaluated by electromanometry, electromyostimulation and dynamic defaecography. Clinical data assessed postoperatively showed good function in 65% of cases, fair in 22.5% and poor in 12.5%. The quality of life in 15 patients with a perineal colostomy and electrostimulated gracilis was significantly better than in 15 patients having an abdomino-perineal resection without gracilis plastic reconstruction.

[Hepatic metastases of colorectal carcinoma. Case reports]

Authors report their clinical experience concerning liver metastases from colorectal cancer. 21 (26%) out of 87 patients observed between 1977 and 1988, underwent hepatic resection. In this group the recorded operative mortality was 4.7% and the postoperative follow-up showed a survival rate of 27% five years after hepatic surgery. Hepatic resection should be considered as the most effective treatment for liver metastases from large bowel cancer. Unfortunately only few patients are suitable for surgery. Alternative treatments for unresectable hepatic recurrences of colorectal cancer still remain a most major problem.

["Wandering spleen": preoperative diagnosis by echotomography of the abdomen (review of the literature and report of a case)]

Splenic wandering is a rare condition of upset position of spleen, due to congenital fault or to excessive looseness of the supporting apparatus of this organ. The literature reports about 180 cases thereof, few of which recognized as such before operation. Ultimate investigations, in this limited number of preoperative diagnoses, resulted angiography and hepato-splenic scintigraphy; only three times the diagnosis was correctly placed through ultra-sounds. The authors show a case, confirmed by the operative report, where the ultrasonic test allowed to place the diagnosis with certainty, and, due to a particular lot of circumstances, proved to be better than TAC.

Continuous intravascular monitoring of pO2 and pCO2. A comparative in vitro-in vivo study

Two electrodes placed at the tip of catheters for in vivo determinations of PCO2 and PO2 respectively, were tested in dogs. Results were satisfactory when compared to a highly accurate reference method, correlation coefficients were close to 1 (P less than 10(-9)). Means of the differences were respectively --1.74 +/- 1.14 toor for the PO2 probe (P less than 0.01) and --1.62 +/- 0.72 torr for the PCO2 sensor (P less than 0.0001). While no drift was detected in the PCO2 electrode, that of the PO2 was significant but negligible compared to the variability of measurements. Thus, for PCO2 values between 20 and 85 torr, and PO2 values between 20 and 140 torr, in vivo monitoring is sufficiently reliable for clinical use.

In vivo measurements of oxyhaemoglobin saturation by a fiberoptic catheter. The effects of variations in pH and haematocrit

The development of plastic fiberoptic catheters, cheaper and less fragile than glass ones, has enabled the more widespread use of oxyhaemoglobin saturation (SO2) monitoring. They allow direct determinations of SO2 to be made, using reflection spectrophotometry. The purpose of the present work was to evaluate the accuracy of SO2 measurements as provided by these catheters. The studies were performed in dogs, with large variations of SO2, acid-base balance and haematocrit levels.