Assessment of phylogenetic sensitivity for reconstructing HIV-1 epidemiological relationships

This review discusses the molecular interaction of proteins encoded by porcine circoviruses type 1 (PCV1) and type 2 (PCV2) with respect to the putative role for disease induction. Besides protein:protein interactions also proteins binding to PCV DNA are covered. Moreover, new approaches are considered which have been generated by genomic and proteomic techniques. PCV are still an enigma, when communication with the host and induction of disease are concerned. This is remarkably, since comparison of two viruses with a size of less than 2000 nts should easily identify the molecular trigger responsible for pathogenicity of PCV2. Since scientific life isn't all beer and skittles we have to accept that this conundrum may be solved only in a long time range. The good news is that some common themes become visible and that certain aspects of the cell life cycle have been identified to be involved in interaction with the pathogen.     

A unique case of a four-level fracture of the fibula

The case of a 36-year-old pedestrian hit by a motorcycle and suffering a fibular fracture is presented. Complete clinical and radiographic evaluation showed that the fibula was involved in four different anatomical sites without involvement of the tibial diaphysis. Careful evaluation of the injured person demonstrated accompanied lesions at other sites as a result of multiple mechanisms involved. Review of the literature revealed that fractures of the fibula are not rare injuries and are usually due to a direct force applied to this bone. Fractures in more than two different anatomical sites are quite uncommon, making this case of four fractures without involvement of the tibial diaphysis a unique case as far as we know. We concluded that a multiplicity of levels in the fibular fracture should alert the surgeon to search for accompanying traumatic lesions of the neighboring joints that, if left untreated, could lead to a less than satisfactory result.     

Failure in the form of disassociation of a hinged total knee arthroplasty

Hinged total knee arthroplasty is a useful solution in cases of severe bone loss, ligamentous laxity and, of course, revision where these conditions are usually present. In revision arthroplasty, varying rates of success have been reported and the implants fail with symptoms of septic or aseptic loosening. Dislocation of the prosthesis is a rare mode of failure of constrained implants while disassociation of a fully hinged implant is extremely rare. One such case of a failed hinged total knee arthroplasty, as a result of disassociation of the hinging mechanism, is presented. Our search of the literature has not revealed an analogous case report.     

Electric stimulation and hyperbaric oxygen therapy in the treatment of nonunions

Up to 10% of the fractures occurring annually in the U.S. end up in non-union or delayed union. Classical treatment with osteosynthesis and bone grafting is not always successful. Alternatives in treatment have long ago been considered. This article presents current concepts in treatment with electrical stimulation and hyperbaric oxygen, the mechanisms of action, experimental and clinical evidence of their application.     

Monte Carlo simulation of energy-deposit clustering for ions of the same LET in liquid water

This work presents a Monte Carlo study of energy depositions due to protons, alpha particles and carbon ions of the same linear-energy-transfer (LET) in liquid water. The corresponding track structures were generated using the Geant4-DNA toolkit, and the energy deposition spatial distributions were analyzed using an adapted version of the DBSCAN clustering algorithm. Combining the Geant4 simulations and the clustering algorithm it was possible to compare the quality of the different radiation types. The ratios of clustered and single energy depositions are shown versus particle LET and frequency-mean lineal energies. The estimated effect of these types of radiation on biological tissues is then discussed by comparing the results obtained for different particles with the same LET.     

Monte-Carlo dosimetry on a realistic cell monolayer geometry exposed to alpha particles

The energy and specific energy absorbed in the main cell compartments (nucleus and cytoplasm) in typical radiobiology experiments are usually estimated by calculations as they are not accessible for a direct measurement. In most of the work, the cell geometry is modelled using the combination of simple mathematical volumes. We propose a method based on high resolution confocal imaging and ion beam analysis (IBA) in order to import realistic cell nuclei geometries in Monte-Carlo simulations and thus take into account the variety of different geometries encountered in a typical cell population. Seventy-six cell nuclei have been imaged using confocal microscopy and their chemical composition has been measured using IBA. A cellular phantom was created from these data using the ImageJ image analysis software and imported in the Geant4 Monte-Carlo simulation toolkit. Total energy and specific energy distributions in the 76 cell nuclei have been calculated for two types of irradiation protocols: a 3 MeV alpha particle microbeam used for targeted irradiation and a 23?Pu alpha source used for large angle random irradiation. Qualitative images of the energy deposited along the particle tracks have been produced and show good agreement with images of DNA double strand break signalling proteins obtained experimentally. The methodology presented in this paper provides microdosimetric quantities calculated from realistic cellular volumes. It is based on open-source oriented software that is publicly available.     

Clefts of the lip and palate: is the Internet a trustworthy source of information for patients?

Great numbers of patients use the Internet to obtain information and familiarize themselves with medical conditions. However, the quality of Internet-based information on clefts of the lip and palate has not yet been examined. The goal of this study was to assess the quality of Internet-based patient information on orofacial clefts. Websites were evaluated based on the modified Ensuring Quality Information for Patients (EQIP) instrument (36 items). Three hundred websites were identified using the most popular search engines. Of these, 146 were assessed after the exclusion of duplicates, irrelevant sites, and web pages in languages other than English. Thirty-four (23.2%) web pages, designed mostly by academic centres and hospitals, covered more than 22 items and were classified as high-score websites. The EQIP score achieved by websites ranged between 4 and 30, out of a total possible 36 points; the median score was 19 points. The top five high-scoring web pages are highlighted. The overall quality of Internet-based patient information on orofacial clefts is low. Also, the majority of web pages created by medical practitioners have a marketing perspective and in order to attract more patients/customers avoid mentioning the risks of the reconstructive procedures needed.