ONCOPROTEINS AND TUMOR SUPPRESSOR PROTEINS IN CONGENITAL SACROCOCCYGEAL TERATOMAS

Congenital sacrococcygeal teratoma SCT is the most common germ cell tumor of infancy and childhood with a female preponderance. Most SCTs are diagnosed at birth, are benign, and consist of fully differentiated, mature tissues. Tumorigenesis of SCTs remains poorly understood. Almost nothing is known about possible oncogene activation or tumor suppressor inactivation in these rare tumors. We describe the presence of various oncoproteins and tumor suppressor proteins in eight cases of congenital SCT. The following oncogenes were examined: ras family c-H-, c-N-, and c-K-ras , early genes fos, jun , and tumor suppressor genes p53 and nm23-H-1 . There was no relationship between the intensity of expression of these oncoproteins and tumor suppressor genes and the following parameters: tumor size, age, and survival of the patients. We did not observe any difference, however, between the expression of the examined oncogenes and tumor suppressor genes nm23 and p53 in immature and mature teratomas. Our findings suggest that the ras family of oncogenes, fos and jun oncogenes, and nm23 and p53 tumor suppressor genes are present in congenital SCT, indicating a possible role in genesis and development of these tumors.     

Improvement to the Corrosion Resistance of Ti-Based Implants Using Hydrothermally Synthesized Nanostructured Anatase Coatings

The electrochemical behavior of polycrystalline TiO₂ anatase coatings prepared by a one-step hydrothermal synthesis on commercially pure (CP) Ti grade 2 and a Ti13Nb13Zr alloy for bone implants was investigated in Hank’s solution at 37.5 °C. The aim was to verify to what extent the in-situ-grown anatase improved the behavior of the substrate in comparison to the bare substrates. Tafel-plot extrapolations from the potentiodynamic curves revealed a substantial improvement in the corrosion potentials for the anatase coatings. Moreover, the coatings grown on titanium also exhibited lower corrosion-current densities, indicating a longer survival of the implant. The results were explained by considering the effects of crystal morphology, coating thickness and porosity. Evidence for the existing porosity was obtained from corrosion and nano-indentation tests. The overall results indicated that the hydrothermally prepared anatase coatings, with the appropriate morphology and surface properties, have attractive prospects for use in medical devices, since better corrosion protection of the implant can be expected.     

Solid lipid microparticles containing loratadine prepared using a Micromixer

Solid lipid microparticles were investigated as a taste-masking approach for a lipophilic weak base in a suspension. The idea was that the drug concentration in the aqueous phase of a suspension might be reduced by its partitioning into the solid lipid particles. Loratadine, as a model drug, was used to prepare Precirol® ATO 5 microparticles by a Micromixer. The effects of three process variables: drug loading, PVA concentration and water/lipid ratio on the microparticle size, encapsulation efficiency, surface appearance, in-vitro release and drug partitioning in a suspension were studied. Loratadine release was slow in simulated saliva and very fast at the pH of stomach. In suspension of loratadine lipid microparticles, drug was released into the aqueous phase to the same concentration as in a drug suspension. Therefore, the usefulness of these microparticles for taste-masking in liquids is limited. However, they might be useful for taste-masking in solid dosage forms.     

Comparison of IgM-MGUS and IgG-MGUS polyneuropathy

Objective – To compare the clinical and electrodiagnostic features and response to treatment in patients with IgM-MGUS and IgG-MGUS associated polyneuropathy. Material and methods – Retrospective review of 34 consecutive patients with MGUS associated neuropathy evaluated over 5 years. Results – There were 19 patients with IgM-MGUS and 15 with IgG-MGUS. There were no differences in age, duration of symptoms, or distribution of motor and sensory symptoms or signs. IgM-MGUS patients had prolonged distal latencies of the median and ulnar motor potentials, greater slowing of the peroneal nerve conduction velocity and more often absent ulnar sensory potentials. Half of the patients in both groups improved following immunotherapy. Conclusion – IgM-MGUS patients had more severe dernyelination on the nerve conduction studies, but there were no clinical features that differentiated the 2 groups. IgM and IgG-MGUS patients improved with plasma exchange and other immune therapies. Anti-MAG antibodies failed to distinguish a subgroup of patients with IgM-MGUS neuropathy     

Pulmonary MnSOD is nitrated following hepatic ischemia-reperfusion

BACKGROUND: Ischemia-reperfusion (I/R) of remote organs is a common cause of lung injury. We observed that lung injury after partial hepatic I/R in mice coincides with the appearance of 3-nitrotyrosine (NT) in the lung tissue, a marker of peroxynitrite involvement and oxidant stress. Peroxynitrite can cause mitochondrial dysfunction by inactivation of manganese superoxide dismutase (MnSOD), the major antioxidant enzyme in mitochondria. Our aims were to examine whether pulmonary MnSOD is a target of nitration following hepatic I/R and whether nitrated MnSOD (N-MnSOD) correlates with acute lung injury. METHODS: Five 20-25-g male C57BL/6 mice underwent laparotomy, and atraumatic occlusion of the portal and arterial blood supply to the upper three lobes of the liver for 90 min. This warm ischemic period was followed by 4 h of reperfusion, and the animals were then euthanized. Lung injury was assessed by LDH and protein levels in bronchoalveolar lavage (BAL) fluid. Pulmonary MnSOD activity in pulmonary homogenates was measured by the cytochrome c reduction method. The presence of N-MnSOD was determined by immunoprecipitation (IP) and Western Blot analysis. Controls (N = 5) underwent sham operation. RESULTS: Elevated plasma transaminases confirmed hepatic injury. Lung injury was demonstrated by elevation in BAL protein and LDH levels (495.7 (48.4) versus 644.9 (37.3) [p < 0.05] and 56.5 (11.8) versus 345.2 (80) [p < 0.01], respectively). Immunoprecipitation and Western blot demonstrated N-MnSOD in the lung tissue of I/R animals but not controls. MnSOD activity decreased following I/R (8.1 (0.7) versus 10.8 (0.3) [p < 0.05]). CONCLUSIONS: Pulmonary MnSOD is both nitrated and inactivated following hepatic I/R and is associated with acute lung injury. These findings suggest that MnSOD incapacitance may contribute to I/R-induced lung injury and provide a therapeutic target in attenuating multisystem injury following hepatic I/R.     

Small bowel ischaemia-reperfusion increases plasma concentrations of oxidised proteins in rats.

OBJECTIVES: To find out whether plasma concentrations of protein carbonyl (a specific marker of oxidative damage of proteins) are increased during intestinal ischaemia-reperfusion and whether they are correlated with von Willebrand's factor (vWF, a marker of endothelial injury) or myeloperoxidase (a marker of neutrophil activation). DESIGN: Randomised experimental study. SETTING: University department of surgery, New Zealand. ANIMALS: Thirty anaesthetised adult Wistar rats. INTERVENTIONS: The sham operated group (n = 10) had laparotomy and isolation of the superior mesenteric artery without clamping. The ischaemia-reperfusion group (IR, n = 10) had the superior mesenteric artery clamped for 1 hour and reperfusion for 15 minutes. The control group (n = 10) had direct puncture of the heart to sample blood. MAIN OUTCOME MEASURES: Plasma concentrations of protein carbonyl, vWF, and myeloperoxidase. RESULTS: Plasma protein carbonyl concentrations were significantly higher in the IR group than in the sham group (p < 0.02, Mann-Whitney test, median (range) 0.187 (0.141-0.242) compared with 0.144 (0.121-0.185) nmol/mg) and in the control group (p < 0.01, Mann-Whitney test, median (range) 0.187 (0.141-0.242) compared with 0.136 (0.108-0.175) nmol/mg). There was a significant correlation between protein carbonyl and vWF concentrations (r = 0.54, F = 10.9, p < 0.003, linear regression) but not with those of myeloperoxidase. CONCLUSION: Intestinal ischaemia-reperfusion caused an increase in the plasma protein carbonyl concentration, which is possibly produced by endothelial cells.     

Large complex odontoma of the left maxillary sinus

Odontomas as a group are the most common odontogenic neoplasms. They are mixed lesions containing fully formatted dental tissues, both epithelial and mesenchymal, and are usually found during a routine radiographic examination or as a factor in noneruption. Odontomas can be divided into two types: the complex and the compound odontoma. Both types are composed of enamel, dentin, cementum and pulp tissues, but in complex odontomas the tissues are arranged in a haphazard fashion with no discernible dental structures, whereas in compound odontomas the dental tissues exist in a more regular pattern so that the lesion consists of tooth-like structures. We report a case of a 23-year-old man with a large complex odontoma involving the left maxilla and maxillary sinus with clinical, radiographic and histological findings. Because of the size of the mass and its clinical course, benign neoplasms were considered in the differential diagnosis. Surgery was the treatment of choice, and recurrence of the lesion is not expected.     

Silica-lipid hybrid microcapsules: influence of lipid and emulsifier type on in vitro performance

This study reports on the physicochemical characterisation and in vitro investigations of macro-porous silica-lipid hybrid (SLH) microcapsules when formulated using various lipids: long-chain triglycerides (LCT), medium-chain triglycerides (MCT), medium-chain mono-, diglycerides (MCMDG); and emulsifiers: anionic lecithin and cationic oleylamine. For the lipophilic compound coumarin 102 (logP=4.09), a complete and immediate in vitro release was attained for the SLH microcapsules under simulated intestinal sink conditions. The in vitro digestion study of various types of SLH microcapsules demonstrates: (i) reduced variability and enhanced lipid digestibility for the MCMDG-based microcapsules (i.e. 90-100% lipolysis) in comparison with an equivalent lipid solution and emulsion (50-90% lipolysis); and (ii) more controllable digestion kinetics for the LCT-based microcapsules which produce a lipolysis rate higher than that of a lipid solution but lower than that of a lipid emulsion. The drug phase partition results show approximately 5- to 17-fold increase in the drug solubilisation degree resulting from the digestion of MCT and MCMDG-based microcapsules (116 μg/mL), and LCT-based microcapsules (416 μg/mL) in comparison with the blank micellar medium (24 μg/mL). In conclusion, the SLH microcapsules could be tailored to manipulate the digestion patterns of both medium- and long-chain lipids in order to maximise the drug solubilisation capacity.     

Continuous physical activity promotes healthy ageing

The growth in the prevalence of chronic diseases of civilization is of concern. In Croatia, diseases of the circulatory system are the main cause of hospitalization amongst people aged >65 and the main cause of death for two thirds of those aged >65. Continuous physical activity in older people stands out as an important factor in the prevention of chronic diseases of civilization, particularly diseases of the circulatory system, but also for other health problems. A survey on the extent of physical activity amongst older people aged >65 carried out in Zagreb (N=449, Croatian Health Survey/2003; CROCAN Project) has shown that 42.8% were physically inactive, whilst only 19.1% were physically active on a daily basis. Physical activity, two to three times per week, which is recommended by WHO, was undertaken by 11.6% of those aged >65. These gerontologic health indicators show that the Programme of preventative measures is insufficiently applied amongst the elderly. This Programme includes primarily kinesiologic measures adapted for the elderly as developed in the study. It is important to ensure that the Programme of continuous physical activity is applied amonst the elderly to promote active healthy ageing. The type of physical activity, its intensity and frequency should be adapted to each individual's health status, their interests, physical condition and the extent of any previous experiences of physical activity.Thus, professional guidance, consultation with kinesiologists for the elderly and general practitioners as well as the collaboration with other medical specialists are necessary.