Subdental synchondrosis and anatomy of the axis in aging: a histomorphometric study on 30 autopsy cases

During skeletal development the two ossification centers of the odontoid process are separated from the corpus of the axis by a subdental synchondrosis. This synchondrosis is thought to close and disappear spontaneously in adolescence although this has never been studied in detail. The basis of the dens is of clinical relevance as type II dens fractures are located here. To characterize the morphological architecture of the axis with particular attention to the subdental synchondrosis, the complete axis was harvested from thirty age-matched and gender-matched patients of the three different age groups at autopsy. The subdental synchondrosis and the bone structure of the dens, the basis of the dens and the body of C2 were analyzed by radiography, histology and quantitative histomorphometry. At the macroscopic level the persistency of the subdental synchondrosis in the adult cervical spine was detected in 87% (26 of 30) of the specimens. Histomorphometry revealed a residual disc blastema with an average size of 25.8% of the sagittal depth of the basis of the dens at this level. Bony integration of the synchondrosis was poor throughout all ages. Histologically a cartilaginous matrix composition of the subdental synchondrosis persisted throughout all groups. The trabecular microarchitecture demonstrated a significant reduction of bone volume and trabecular number as well as an increased trabecular separation within the basis of the dens as compared to the corpus or the dens of C2. This histomorphometric data regarding a poor integration of the synchondrosis into the trabecular network and the reduced bone mass within the basis of the dens might offer a previously underestimated explanation for the occurrence of type II dens fractures and their association with pseudoarthrosis, respectively.Matthias Gebauer and Christian Lohse contributed equally to this study and therefore share first authorship.     

Chromogenic ionophore-based methods for spectrophotometric assay of sodium and potassium in serum and plasma

We report spectrophotometric methods for quantifying sodium and potassium in serum and plasma without sample pretreatment or solvent-extraction steps. The methods are based on novel chromogenic ionophores characterized by molecular structures highly preorganized for binding, which result in exceptionally high sensitivity and selectivity (negligible responses to sodium at 80 to 200 mmol/L in the potassium assay and to potassium at 0 to 10 mmol/L in the sodium assay). The within-run imprecisions are comparable with those for ion-selective electrodes (for K, 1.0% at 4.5 mmol/L; for Na, 1.1% at 136 mmol/L); the analytical range is 2-10 mmol/L for potassium, 80-170 mmol/L for sodium. The results for greater than 100 patients' samples correlated well with results obtained with ion-selective electrodes (r = 0.99 for K, 0.97 for Na). The ready-to-use aqueous reagents will be available under the trade name of ChromoLyte for use with Technicon's RA family of clinical analyzers.     

Residues involved in the antigenic sites of transmissible gastroenteritis coronavirus S glycoprotein.

The S glycoprotein of transmissible gastroenteritis virus (TGEV) has been shown to contain four major antigenic sites (A, B, C, and D). Site A is the main inducer of neutralizing antibodies and has been previously subdivided into the three subsites Aa, Ab, and Ac. The residues that contribute to these sites were localized by sequence analysis of 21 mutants that escaped neutralization or binding by TGEV-specific monoclonal antibodies (MAbs), and by epitope scanning (PEPSCAN). Site A contains the residues 538, 591, and 543, which are essential in the formation of subsites Aa, Ab, and Ac, respectively. In addition, mar mutant 1B.H6 with residue 586 changed had partially altered both subsite Aa and Ab, indicating that these subsites overlap in residue 586; i.e. this residue also is part of site A. The peptide 537-MKSGYGQPIA-547 represents, at least partially, subsite Ac which is highly conserved among coronaviruses. This site is relevant for diagnosis and could be of interest for protection. Other residues contribute to site B (residues 97 and 144), site C (residues 50 and 51), and site D (residue 385). The location of site D is in agreement with PEPSCAN results. Site C can be represented by the peptide 48-P-P/S-N-S-D/E-52 but is not exposed on the surface of native virus. Its accessibility can be modulated by treatment at pH greater than 11 (at 4 degrees) and temperatures greater than 45 degrees. Sites A and B are fully dependent on glycosylation for proper folding, while sites C and D are fully or partially independent of glycosylation, respectively. Once the S glycoprotein has been assembled into the virion, the carbohydrate moiety is not essential for the antigenic sites.     

ATTITUDES TOWARDS AND KNOWLEDGE OF OCCUPATIONAL SKIN DISEASE AMONGST SUPPORT PERSONNEL

Liaison with support personnel is important in the management of workers with occupational skin disease (OSD). This study shows that there are many areas of concern regarding the knowledge and understanding of OSD in these groups. There needs to be a comprehensive education programme concerning OSD within the working community and support personnel. Dermatologists need to simplify their "language' in the reporting of OSD. Insurers need to take a more sympathetic attitude towards the partially fit worker. Rehabilitation personnel must become more familiar with OSD.     

Accumulation of organic contaminants in sentinel mallards utilizing confined disposal facilities at Hamilton Harbour,Lake Ontario,Canada

Organochlorine analysis was performed on adult and juvenile farm-raised mallards (Anas platyrhynchos) released and collected at three experimental sites in southern Ontario: Hamilton Harbour Confined Disposal Facility (CDF); Winona Sewage Lagoons (SL); and Big Creek Marsh, Canada. Collections were scheduled at 10, 30, and 70 days after release. Hamilton Harbour CDF and Winona SL are known to be contaminated whereas Big Creek Marsh is a relatively clean, natural site. All sites are important resting and feeding areas for migratory and resident waterfowl. Breast muscle concentrations of polychlorobiphenyls (PCBs) in ducks collected 10 days after release (160.8 g/kg, wet wt) at Hamilton Harbour CDF were more than 5300 times greater than day 0 birds (0.03 g/kg). All ducks collected from Hamilton Harbour CDF had PCB concentrations exceeding Health and Welfare Canada and United States Food and Drug Administration (FDA) guidelines for edible poultry. Concentrations of DDE (216.9 g/kg), hexachlorobenzene (0.9 g/kg), dieldrin (1.9 g/kg), and 1,2,4,5,-tetrachlorobenzene (24.9 g/kg) were significantly elevated in ducks utilizing Winona SL. Concentrations of 1,2,3,4-tetrachlorobenzene, mirex, and photomirex were elevated at one or more of the sites. Ducks from Big Creek Marsh had lower contaminant concentrations than ducks from the other study sites. It is not clear whether bioaccumulation of organochlorines at these sites would pose a potential hazard to migratory and resident mallards; however, other duck species such as diving ducks that have more contact with sediments and sediment-derived foods would probably be at much higher risk.     

Therapieprinzipien beim Lokalrezidiv des Rektumkarzinoms

The aim of treatment in isolated locally recurrent rectal cancer is R0 resection, which is possible in 30%. Because of the high rate of surgical complications after repeat surgery in the pelvis, preoperative staging has to be precise to estimate the extent and location of the recurrent rectal cancer. After exclusion of distant metastases, surgery should be considered following preoperative radiochemotherapy if possible. When a curative treatment concept is not indicated, radiotherapy is the best treatment choice. This paper presents various tabularised summaries about therapeutic strategies in isolated locally recurrent rectal cancer.     

Boviner Perikardpatch als Bypassmaterial in der Infektsituation

Prosthetic graft infection is one of the most common vascular complications. It must be treated individually. In addition to autologous reconstruction, numerous therapeutic concepts are available. An alternative treatment includes bovine pericardium as a prosthetic replacement material. A case study documents the simple process for making vascular transplants of any size.     

CT-guided high-dose-rate brachytherapy of unresectable hepatocellular carcinoma

Strahlentherapie und Onkologie - The purpose of the present study was to evaluate the clinical outcome of CT-guided high-dose-rate brachytherapy (CT-HDRBT) in patients with unresectable...