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To gain principal insight into fixation techniques of a posteromedial split fragment in bicondylar tibial plateau fractures. A computer simulation was performed, applying the finite-element method (FEM) to compare four methods of fixation of the posteromedial split fragment: lateral plate (model 1), lateral plate and kickstand screw (model 2), lateral plate and two antero-posterior lag screws (model 3), and lateral and posteromedial plate (model 4). The displacement of the fragment and material stresses in implants and bone under 2500 N axial load were analyzed. Maximal displacement of the posteromedial split fragment of 2.8 mm was found with a sole lateral plate. An added kickstand screw decreased the displacement to 1.46 mm. Added lag screws improved stability by a factor 4, with a maximal displacement of 0.76 mm. The double-plate configuration revealed 0.27 mm, a decrease of the displacement by a factor 10 compared to model 1. An additional analysis of posteromedial fragment displacements with osteoporotic bone, simulated by dividing the elastic modulus of the bone by a factor 2, turned out to be of relevant impact. For model 1, the calculations did not converge. The influence of bone quality was found to be 70% in model 2, 60% in model 3, and 40% in model 4. The results indicate that the additional fixation of a posteromedial split fracture by plate osteosynthesis might be advantageous in bicondylar tibial plateau fractures treated with lateral plating. This might be even more important in patients with low bone quality.

There appears to be a relative absence of studies that have examined the prevalence of cognitively intact individuals who reside in extended care facilities. Prevalence data were collected on 296 persons who resided in 3 extended care nursing facilities in Central Virginia. Cognitive intactness was evaluated via the Minimum Data Set Cognitive Performance Scale (CPS) and an author-generated survey (i.e., Cognitively Intact Survey [CI Survey]) of select nursing staff members at each facility. The Mini-Mental State Examination (MMSE) was utilized to examine the accuracy of the two measures in identifying cognitive intactness. Findings indicated that prevalence rates of cognitively intact residents varied as a function of the measures utilized to assess intactness. Specifically, a significantly greater proportion of the total sample of residents was judged to be cognitively intact via the CI Survey (34.12%) as compared to the CPS (26.01%). The level of interjudge agreement between the two measures was found to be moderately high (K = 0.68). When the MMSE was employed to verify individuals' levels of intactness, the percentages of residents predicted to actually be cognitively intact were somewhat lower for each measure. Specifically, based on the data obtained via the CI Survey, 22.75% of the total sample were predicted to actually be cognitively intact, whereas 17.85% of the sample were predicted to be intact based on the CPS results. Findings are discussed in light of factors that may have contributed to the differential prevalence rates of cognitively intact individuals obtained across the measures utilized in this study. Concerns regarding the utilization of the MMSE as a criterion measure of cognitive intactness in persons residing in extended care nursing facilities are provided, along with data on the living environments/roommate statuses of those residents judged to be intact via the CI Survey. Implications for the design of future extended care nursing units, as well as future research, are also included.

Psychologists are increasingly asked to make decisions regarding patient candidacy for transplantation. Despite the growing incidence of lung transplantation, normative research regarding cognitive functioning and end-stage obstructive lung disease is lacking. Hence, data are presented on 100 consecutively referred candidates for lung transplantation. The group data suggest essentially normal functioning on most cognitive tests for the majority of transplant candidates. Exceptions were seen on measures of attentional set shifting and short-term visual memory, which were impaired in nearly one fourth of this population. Additionally, one half of the patients displayed deficient performance on the Buschke Selective Reminding Test, with subjects at greater risk for severe rather than mild deficits. Unlike prior research, our group data suggest that there is potential risk of short-term noncontextual verbal memory difficulties because of end-stage pulmonary disease. Personality testing data, e.g., elevations on MMPI-2 scales measuring depression and anxiety, are also discussed.

Squamous cell cancer of the oral cavity mainly occurs in older patients or in patients with alcohol or nicotine abuse. Younger patients are seldom involved. The case of a 27-year-old woman with a squamous cell cancer of the right cheek will be presented. Without any risk factors, an immune defect resulting in chronic Candida infection of the oral cavity seems to be responsible for the carcinogenesis.

Various critics or "method skeptics" have contended that clinical neuropsychology is not sufficiently developed as a science to be offered as evidence in legal or trial proceedings. The present article attempts to balance the extreme position of the method skeptics with an overview of legal and research data that support forensic applications of neuropsychology. It is suggested that clinical evidence can usefully inform legal decision making and that the modern trend has been for courts to be increasingly open to such expert testimony. The relevance of studies of clinical judgement, experience, and actuarial prediction is discussed, and neuropsychological assessment validity is specifically addressed. It is concluded that the arguments of the method skeptics should guide future research and caution forensic neuropsychologists, but that a retreat from the courtroom is unwarranted.

Plasmid pRP761 is a derivative of the promiscuous plasmid RP4, which has a Tn76 insert 1.8 kb from its EcoRI site within the trfB region (Barth 1979). This mutation was pleiotropic, having three effects: the plasmid is unstably maintained in E. coli, it reduces the growth rate of its host and it has suffered a reduction in host-range. We show that pRP761 has reduced expression from both its korA and korB genes and that Tn76 has inserted between them. Fragment exchange experiments showed that this is the only mutant region in pRP761 and is therefore solely responsible for the pleiotropic effects. A spontaneous deletion derivative pRP761-6 has lost Tn76 and its adjacent kilA and korA genes: it has reacquired stability, does not inhibit host growth but is still reduced in its host-range. The provision of cloned korA+ in trans complements the first two phenotypic effects in pRP761 to a large extent, but neither korA+ alone nor korA+ with korB+ complements the host-range reduction in pRP761 or pRP761-6. A possible explanation for these results is that there is a site between korA and korB, affected by the Tn76 insert, that is essential to stable replication of these plasmids in some of their bacterial hosts.

The glutamate dehydrogenase gene of Escherichia coli has been cloned into broad host-range plasmids and can complement glutamate synthase mutants of Methylophilus methylotrophus. Assimilation of ammonia via glutamate dehydrogenase is more energy-efficient than via glutamate synthase, thus the recombinant organism converts more growth substrate, methanol, into cellular carbon.