Scanning electron, 3D-confocal and stereotactic microscopies morpho-structural analysis of antibiotic-loaded cement porosity in three different formulations.

Chronic osteoarticular infections such as osteomyelitis or periprosthetic joint infection (PJI) have become a growing problem over the years. The "gold standard" in local antibiotic administration is still the antibiotic-loaded acrylic bone cement (ALABC) which is used in both prophylaxis, because it has been shown it can reduce the risk of infection and used in therapy during a "two-stage surgery" in PJI or in chronic osteomyelitis. We performed morphological analysis of three different formulations of antibiotic-loaded cement (ALABC) using techniques of light microscopy, scanning electron microscopy (SEM) and 3D immunofluorescence, in order to explain how the morphological aspects of cement could influence and modulate antibiotic elution.

Morphofunctional compensation of masseter muscles in unilateral posterior crossbite patients.

Unilateral posterior crossbite is a widespread, asymmetric malocclusion characterized by an inverse relationship of the upper and lower buccal dental cusps, in the molar and premolar regions, on one side only of the dental arch. Patients with unilateral posterior crossbite exhibit an altered chewing cycles and the crossbite side masseter results to be less active with respect to the contralateral one. Few studies about morphological features of masticatory muscle in malocclusion disorders exist and most of these have been performed on animal models. The aim of the present study was to evaluate morphological and protein expression characteristics of masseter muscles in patients affected by unilateral posterior crossbite, by histological and immunofluorescence techniques. We have used antibody against PAX-7, marker of satellite cells, and against α-, ß-, γ-, δ-, ε- and ζ-sarcoglycans which are transmembrane glycoproteins involved in sarcolemma stabilization. By statistical analysis we have evaluated differences in amount of myonucley between contralateral and ipsilateral side. Results have shown: i) altered fibers morphology and atrophy of ipsilateral muscle if compared to the contralateral one; ii) higher number of myonuclei and PAX-7 positive cells in contralateral side than ipsilateral one; iii) higher pattern of fluorescence for all tested sarcoglycans in contralateral side than ipsilateral one. Results show that in unilateral posterior crossbite hypertrophic response of contralateral masseter and atrophic events in ipsilateral masseter take place; by that, in unilateral posterior crossbite malocclusion masticatory muscles modify their morphology depending on the function. That could be relevant in understanding and healing of malocclusion disorders; in fact, the altered balance about structure and function between ipsilateral and contralateral muscles could, long-term, lead and/ or worsen skeletal asymmetries.

Histochemical and morphological aspects of fresh frozen bone: a preliminary study.

Bone graft are used in dentistry for the reconstruction of severely atrophic jaws. Fresh frozen bone has no osteogenic property but it has osteoconductive and osteoinductive properties because its matrix contains growth factors such as vascular endothelial growth factor. The purpose of the present study was to evaluate morphological and protein expression characteristics of fresh frozen bone before graft and after six months of graft in patients who needed maxillary reconstruction. After 6 month of graft we observed the presence of viable bone as evidenced by full osteocyte lacunae and by the presence of RANKR, osteocalcin positive cells and vascular endothelial growth factor. In conclusion, our findings show that the fresh frozen bone after six month of graft is for the most part viable bone, encouraging its use as an alternative to autogenous bone for reconstructing maxillary bone defects prior to implant.

Sarcoglycan complex in masseter and sternocleidomastoid muscles of baboons: an immunohistochemical study.

The sarcoglycan complex consists of a group of single-pass transmembrane glycoproteins that are essential to maintain the integrity of muscle membranes. Any mutation in each sarcoglycan gene causes a series of recessive autosomal dystrophin-positive muscular dystrophies. Negative fibres for sarcoglycans have never been found in healthy humans and animals. In this study, we have investigated whether the social ranking has an influence on the expression of sarcoglycans in the skeletal muscles of healthy baboons. Biopsies of masseter and sternocleidomastoid muscles were processed for confocal immunohistochemical detection of sarcoglycans. Our findings showed that baboons from different social rankings exhibited different sarcoglycan expression profiles. While in dominant baboons almost all muscles were stained for sarcoglycans, only 55% of muscle fibres showed a significant staining. This different expression pattern is likely to be due to the living conditions of these primates. Sarcoglycans which play a key role in muscle activity by controlling contractile forces may influence the phenotype of muscle fibres, thus determining an adaptation to functional conditions. We hypothesize that this intraspecies variation reflects an epigenetic modification of the muscular protein network that allows baboons to adapt progressively to a different social status.

Slice-thickness evaluation in CT and MRI: an alternative computerised procedure.

PURPOSE: The efficient use of computed tomography (CT) and magnetic resonance imaging (MRI) equipment necessitates establishing adequate quality-control (QC) procedures. In particular, the accuracy of slice thickness (ST) requires scan exploration of phantoms containing test objects (plane, cone or spiral). To simplify such procedures, a novel phantom and a computerised LabView-based procedure have been devised, enabling determination of full width at half maximum (FWHM) in real time. MATERIALS AND METHODS: The phantom consists of a polymethyl methacrylate (PMMA) box, diagonally crossed by a PMMA septum dividing the box into two sections. The phantom images were acquired and processed using the LabView-based procedure. RESULTS: The LabView (LV) results were compared with those obtained by processing the same phantom images with commercial software, and the Fisher exact test (F test) was conducted on the resulting data sets to validate the proposed methodology. CONCLUSIONS: In all cases, there was no statistically significant variation between the two different procedures and the LV procedure, which can therefore be proposed as a valuable alternative to other commonly used procedures and be reliably used on any CT and MRI scanner.

Balance and posture in the elderly: an analysis of a sensorimotor rehabilitation protocol.

Regular training programs are a concrete means to prevent and/or reduce functional decline due to aging. A multisensory training approach seems to obtain better results in the elderly with regard to both balance and quality of life. Forty subjects (age 65+/-10 years, height 165+/-4 cm, weight 73.0+/-4.6 kg) were randomized into two groups (GrHu and GrCl). Participants in the GrHu group received 3 months of balance and postural training, 3 sessions per week, with the use of a multisensory training approach. Those in the GrCl group received 3 months of training with a classical rehabilitation protocol that included isotonic training for the lower limbs and spine. With regard to walking, there was an improvement in step symmetry for participants in the GrHu group compared to baseline (0.93+/-0.09 vs. 0.84+/-0.1; p<0.05). Further, all subjects in the GrHu group showed a significant reduction in the energy used during a 4-min walk. Analysis of stabilometry data also showed a significant improvement in balance for those in the GrHu group, which was independent of age or gender. The multisensory training approach yields an improvement of balance in the elderly, which reduces the risk of falls. The observed improvement is significantly greater than that seen with the classical training program.

Wired and wireless network solution for the integrated management of data and images.

PURPOSE: This paper reports on the authors' experience with the implementation of an internal network with open structure model (extranet) inside a private healthcare institution. MATERIALS AND METHODS: An integrated clinical-administrative internal network was set up within a private orthopaedic hospital with about 90 beds. The system consists of a DICOM-based HIS-RIS network connected to the radiological department PACS, and is implemented through an internal web-server over a mixed wired-wireless network. The strengths of the system are: the use of an open-structure model allowing external access; the inclusion of a wireless component of the network, which extends access to mobile workstations; the possibility of conducting the quality assurance procedures directly from outside the hospital. RESULTS: The system allows the diagnostic images generated by the various equipment (Rx, CT, NMR, etc.) to be filed in compliance with the AIPA (Italian Authority for Information Technology in Public Administration) regulations; the images and electronic clinical records are made available to the departments by means of an internal web server. The use of the wireless component of the network has several additional advantages: for example, it enables healthcare personnel to view clinical records and diagnostic images on their laptop monitors from any department or hospital room, and it makes every change or addition readily available to the healthcare personnel. In this way the laptops represent an evolution of the traditional paper-based clinical record. Moreover, a direct connection was set up with the University Department of Image Processing with a view to increasing the hospital's efficiency and productivity. This connection allows adequate quality assurance procedures to be carried out on the radiological department equipment without requiring the physical presence of specialised staff, and therefore reducing costs and machine idle time. A second phase of the project is currently being tested. This consists in the collaboration of a pilot group of twenty family doctors to test system functionality during telebooking, teleconsulting and information exchange with specialists, as well as the possibility of keeping track of the patients' diagnostic work-up and clinical therapy. DISCUSSION AND CONCLUSIONS: In the context of the Italian healthcare system, the creation of adequate hospital information systems (HIS) and their integration with PACS was at first a prerogative of a few large hospitals. Recently, however, more and more patients have started to approach the healthcare world directly through the Internet, at first to request only information (leading to the diffusion of specialised web sites, or portals) and later also e-services. This new demand led us to create a Hospital Information System able to organise the internal activity of the hospital and offer several external services such as telebooking and teleconsulting, and therefore increase the hospital's efficiency and productivity. a method of choice for following patients after interventional procedures or as a mass-screening tool to select patients to be referred for coronary angiography.

A new method to assess the fluidodynamic behaviour of an angiographic contrast agent.

PURPOSE: To propose a new method for the assessment of the fluidodynamic behaviour of angiographic contrast agents. The method enables measurement of the spatial distribution and time dependence of the contrast agent along a pseudo-vessel on images obtained with an X-ray image intensifier. MATERIAL AND METHODS: A particular phantom was devised consisting of a plexiglas box with an insert into which a latex tube with a 0.4 cm in diameter was placed in order to simulate the tortuous flow of a blood vessel. The box, which is filled with water to simulate the thickness of a normal patient, is connected to an injection and pumping system which serve to keep the contrast agent flowing in the pseudo-vessel tube. The pseudo-vessel tube was filled with plain water in one case and with saline solution in another case to assess their different dilution capabilities. The phantom and the flow of contrast agent were imaged with a conventional X-ray image intensifier system and the images were stored in digital format during 35 second acquisitions at a speed of 4 frames per second; for any frame it is possible to measure the mathematical contrast in any position in the image. Further, a diagram showing the time dependence of the spatial distribution of the mathematical contrast is proposed. The X axis shows the spatial distribution of the mathematical contrast, whereas the Y axis shows its temporal variation with a gray level proportional to the mathematical contrast value. By building an horizontal profile of this diagram one can obtain the spatial distribution at a fixed time, while by building a vertical profile one can obtain the temporal variation at a fixed point. Several different contrast agents were so tested. RESULTS: The proposed method allows different fluido-dynamic behaviour patterns of contrast agents and flowing media to be shown. Owing to the different chemical characteristics of water and saline solution these media have different dilution capabilities (higher for water) and this is well demonstrated by the diagram profiles obtained for each. The system has also allowed the detection of a particular behaviour of some contrast agents, whose spatial distribution was non uniform even in the last frames, thus showing a tendency to maintain their bolus-nature over time. An interesting feature which can be noticed in all the temporal profiles is the presence of a "pre-bolus", i.e. the contrast is higher at the very beginning of the flow, then decreases and after some time starts to increase again. Though the initial contrast value obviously depends on the iodine concentration employed, the method shows the contrast variation as a function of time is different for different contrast agents. CONCLUSIONS: The method and the equipment proposed provide a good description of the fluidodynamic behaviour of different contrast agents, but do not constitute a reference method for testing haemodynamic behaviour which, "in vivo", is obviously affected by several other chemical and metabolic factors. However, the method allows evaluation of the contrast agents from a physical and fluidodynamic point of view, showing that the iodine content is not the only feature affecting their behaviour. The method can be used in quality control to test the constancy of the physical behaviour of different contrast agents.

Measurement of allergen-induced skin reactions by computerized dynamic telethermography (CDTT).

Cutaneous thermic changes induced by a skin prick test reaction were measured by an infrared thermography camera (computerized dynamic telethermography, CDTT). Changes in skin temperature (T degree) detected by CDTT were compared with the mean diameter of allergen-induced skin reactions. Cutaneous thermic increase detected by CDTT correlated well with the mean wheal diameter measured in millimeters (r = 0.938, p < 0.001). Average coefficient of variation for repeated CDTT measurements was 4.6%. CDTT provides a reproducible and precise method for measuring allergen-induced skin reactions. Moreover, the continuous recording of the skin temperature represents an additional parameter for the quantification of wheal reactions.

Recombinant human erythropoietin inhibits the cutaneous vasodilatation induced by acetylcholine.

We investigated by means of telethermography the contractile response of cutaneous vessels to recombinant erythropoietin (rHuEPO) and the effects of this hormone on the vasodilatation induced by either acetylcholine, which is endothelium-dependent, and nitroprusside, which is endothelium-independent. Experiments were carried out in 12 healthy volunteers. Graded doses of rHuEPO (25, 50, 500 U/min), acetylcholine (7.5 and 15 micrograms/min), sodium nitroprusside (3 and 10 micrograms/min), and saline solution (sodium chloride 0.9%) were infused in the dorsal pedal artery of the lower limb. rHuEPO reduced the cutaneous temperature in a dose-dependent manner compared to the saline solution, thus suggesting that the hormone causes vasoconstriction. In contrast graded doses of acetylcholine and nitroprusside provoked vasodilatation: in fact both increased the cutaneous temperature compared to controls in a dose-dependent manner. The infusion of vasoconstrictive doses of rHuEPO in association with acetylcholine (15 micrograms/min) reverted the increase in the cutaneous temperature induced by the endothelium-dependent vasodilator. In contrast rHuEPO administered in combination with nitroprusside failed to block the vasodilatation induced by the endothelium-independent vasodilator. Therefore our data suggest that rHuEPO exerts an indirect vasoconstrictive effect and that acetylcholine-induced vasodilatation, which is endothelium-dependent, is blunted by the vasoconstrictive activity of rHuEPO, thus demonstrating that the hormone may impair the synthesis of endothelial nitric oxide.