Main branch stent deformation following difficult side branch rewiring and balloon dilatation. Rare complication of provisional T stenting.

Coronary artery bifurcations are one of the largest challenges in interventional cardiology. Presented is the case of a patient in whom restenosis of a drug-eluting stent (DES) occurred as a consequence of guide wire re-crossing between the main vessel stent struts and the vessel wall in the proximal part of DES, and consequential balloon crushing of the proximal portion of the DES. Initially, the complication was not recognized because of a good angiographic result and absence of intravascular ultrasound (IVUS) guidance during the procedure. During the second procedure, IVUS analysis explained the mechanism of the DES failure. The problem was solved with the implantation of a new DES.

Characterization of trace metal particles deposited on some deciduous tree leaves in an urban area.

In 1996 and 1997 horse chestnut (Aesculus hippocastanum L.) and Turkish hazel (Corulys colurna L.) leaves were sampled at 2 m height in the Belgrade Botanic Garden, located in an urban area with heavy traffic. Using a scanning electron microscope with an energy dispersive X-ray spectroscopy (SEM-EDAX), the size, size distribution, morphology and chemical composition of individual particles were examined on the adaxial and abaxial surfaces of leaf discs of both species. The majority of particles observed on leaves belonged to a class of fine particles (D < 2 microm). Morphological and chemical composition indicated that the most abundant particles were soot and dust with minor constituents such as Pb, Zn, Ni, V, Cd, Ti, As and Cu. Using an electrochemical technique (DPASV), it was possible to measure trace metal concentrations (Pb, Cu, Zn) in a water-soluble fraction of deposits on each single leaf. Trace metal contents in the leaf deposits, increased during the vegetation period for both species and were considerably higher in A. hippocastanum due to different epidermal characteristics. The higher trace metal concentrations in deposits in 1997 reflected greater atmospheric pollution in the Belgrade urban area.

Numerical solutions of differential equations of an ionization chamber: plane-parallel and spherical geometry.

A system of reduced differential equations generally valid for plane-parallel, cylindrical and spherical ionization chambers, which is appropriate for numerical solution, has been derived. The system has been solved numerically for plane-parallel and spherical ionization chambers filled with air. The comparison of the calculated results of Armstrong and Tate, for plane-parallel ionization chambers, and Sprinkle and Tate, for spherical ionization chambers, with the present calculations has shown a good agreement. The calculated values for ionization chambers filled with CO2 were also in good agreement with the experimental data of Moriuchi et al.

Active moss biomonitoring of trace elements with Sphagnum girgensohnii moss bags in relation to atmospheric bulk deposition in Belgrade, Serbia.

Active biomonitoring with wet and dry moss bags was used to examine trace element atmospheric deposition in the urban area of Belgrade. The element accumulation capability of Sphagnum girgensohnii Russow was tested in relation to atmospheric bulk deposition. Moss bags were mounted for five 3-month periods (July 2005-October 2006) at three representative urban sites. For the same period monthly bulk atmospheric deposition samples were collected. The concentrations of Al, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Cd, and Pb were determined by instrumental neutron activation analyses and atomic absorption spectrometry. Significant accumulation of most elements occurred in the exposed moss bags compared with the initial moss content. High correlations between the elements in moss and bulk deposits were found for V, Cu, As, and Ni. The enrichment factors of the elements for both types of monitor followed the same pattern at the corresponding sites.

Monitoring of trace element atmospheric deposition using dry and wet moss bags: accumulation capacity versus exposure time.

To clarify the peculiarities of trace element accumulation in moss bags technique (active biomonitoring), samples of the moss Sphagnum girgensohnii Rusow were exposed in bags with and without irrigation for 15 days up to 5 months consequently in the semi-urban area of Belgrade (Serbia) starting from July 2007. The accumulation capacity for 49 elements determined by ICP-MS in wet and dry moss bags was compared. The concentration of some elements, i.e. Al, V, Cr, Fe, Zn, As, Se, Sr, Pb, and Sm increased continuously with exposure time in both dry and wet moss bags, whereas concentration of Na, Cl, K, Mn, Rb, Cs, and Ta decreased. Irrigation of moss resulted in a higher accumulation capacity for most of the elements, especially for Cr, Zn, As, Se, Br, and Sr. Principal component analysis was performed on the datasets of element concentrations in wet and dry moss bags for source identification. Results of the factor analysis were similar but not identical in the two cases due to possible differences in element accumulation mechanisms.

Contribution to biomonitoring of some trace metals by deciduous tree leaves in urban areas.

Leaves of the deciduous tree species, horse chestnut (Aesculus hippocastanum L.) and Turkish hazel (Corylus colurna L.) were used as accumulative biomonitors of trace metal pollution in the urban area of Belgrade. Using differential pulse anodic stripping voltametry, trace metal concentrations (Pb, Cu, Zn, Cd) were determined at the single leaf level (ten leaves per species, per month), during two successive years with markedly different atmospheric level of trace metals. Increased trace metal concentrations in the leaves of A. hippocastanum reflected elevated atmospheric trace metal pollution, whereas C. colurna L. did not respond accordingly. The contents of Pb and Zn in soil over the same period also followed this trend. Anatomical analyses, in young as well as in old leaves of both species, indicated typical foliar injuries of plants exposed to stressful air conditions. Water relations that correspond to leaf age may have contributed to the considerable trace metal accumulation in leaves.

Complications after treatment of patients with osteogenesis imperfecta with a Bailey-Dubow rod.

The purpose of this study was to analyse the complications using the Bailey-Dubow expanding intramedullary rods in patients with osteogenesis imperfecta. Between 1985 and 1996 intramedullary rodding of 107 long bones with expanding Bailey-Dubow rods was performed in 29 patients suffering from osteogenesis imperfecta. Indications for using rods included osseous deformities and bone deformities in combination with fractures. The average follow-up was 3.5 years (range 2 months to 9 years). The total complication rate in these patients was 63.5% (68 rods). The main complication was rod migration often combined with perforation of joint, bone and soft tissue. Additionally, there was a high incidence of new fractures as well as refractures. Other complications like infections, pseudarthrosis, lack of elongation or over-elongation of the rods, and loosening of the T-piece were only rarely seen. Based on our experience and the information available in the literature, the Bailey-Dubow rod is currently the most successful way to stabilize the growing long bones of patients suffering from osteogenesis imperfecta. However, when using this device, the surgeon as well as the parents of the patient must be aware of the high incidence of complications.