Dissociation of the Medial Prefrontal, Posterior Parietal, and Posterior Temporal Cortex for Spatial Navigation and Recognition Memory in the Rat

Rats with lesions of the medial prefrontal, posterior parietal,or posterior temporal cortex were tested in five spatial navigationtasks, which varied in egocentric or allocentric demands, avisual discrimination task, and two delayed nonmatching-to-sampletasks. Rats with prefrontal lesions were impaired at every spatialnavigation task, whereas rats with posterior parietal lesionshad selective spatial navigation impairments. Rats with prefrontallesions were also impaired at a visual delayed nonmatching-to-sampletask, as they were unable to learn the task, even with no delay.The results are consistent with the idea that the basic planof mammalian cortex includes prefrontal, posterior parietal,and posterior temporal regions, each of which have generallysimilar functions across mammalian taxa. There are, however,species-typical differences that reflect specific ecologicalpressures on the development of the different regions.     

Laying the Cytotaxonomic Foundations of a New Model Grass, Brachypodium distachyon (L.) Beauv.

Brachypodium distachyon is a ubiquitous, temperate grass species which is being developed and exploited as an alternative model to rice, in order to gain access to important syntenic regions of the genomes of less tractable relatives such as wheat. As part of this initiative, this paper describes for the first time the cytotaxonomy of members of the polyploid series of this species, and challenges the assumption that the series evolved simply by chromosome doubling. In situ hybridization using genomic DNA probes and rDNA markers uncovers a hybrid origin of several of the polyploid ecotypes, and sheds light upon the complex evolution of this species and its close relatives.     

The effect of simulator training on clinical skills acquisition, retention and transfer

Context  Prior research has demonstrated that residents have poor clinical skills in cardiology and respirology. It is not clear how these skills can be improved because the number of patients with suitable clinical findings whose cooperation might help residents to better develop these clinical skills is limited.
Objectives  Our objective was to evaluate the effect of training on a cardiorespiratory simulator (CRS) on skills acquisition, retention and transfer.
Methods  We randomly allocated 146 students to CRS training in either chest pain or dyspnoea and compared each student's performance on the clinical presentation in which he or she had received CRS training with performance on the control presentation.
Results  Immediately after training, students were more accurate in identifying abnormal clinical findings on the CRS (70.0% versus 52.2%; d = 7.6, P  < 0.0001) and showed improved diagnostic performance (72.1% versus 55.6%; d = 4.3, P  = 0.0007) on the training clinical presentation. At the end of the course they were still better at identifying abnormal findings (57.1% versus 51.7%; d = 2.5, P  = 0.004) and diagnosing correctly (50.0% versus 38.1%; d = 3.0, P  = 0.002) on problems included in the training clinical presentation. However, they showed no difference between training and control presentations in diagnostic performance when required to transfer their skills between problems (45.9% versus 43.8%; P  = 0.5) or in performance on multiple-choice questions (64.1% versus 63.6%; P  = 0.8).
Conclusions  Students can acquire and retain clinical skills with CRS training, but demonstrate limited ability to transfer these to other problems. Further studies are needed to explore ways of improving learning and transfer with CRS training.     

Gene expression profiles of serous, endometrioid, and clear cell subtypes of ovarian and endometrial cancer.

PURPOSE: The presence of similar histologic subtypes of epithelial ovarian and endometrial cancers has long been noted, although the relevance of this finding to pathogenesis and clinical management is unclear. Despite similar clinical characteristics, histologic subtypes of cancers of the ovary and endometrium are treated according to organ of origin. This study compares the gene expression profiles of analogous histologic subtypes of cancers of the ovary and endometrium using the same genomic platform to determine the similarities and differences between these tumors. EXPERIMENTAL DESIGN: Gene expression profiles of 75 cancers (endometrioid, serous, and clear cell) of the ovary and endometrium, five renal clear cell cancers, and seven normal epithelial brushings were determined using a 11,000-element cDNA array. All images were analyzed using BRB ArrayTools. Validation was done using real-time PCR on select genes and immunohistochemical staining. RESULTS: Comparison across endometrial and ovarian cancers and serous and endometrioid tumors showed expression patterns reflecting their organ of origin. Clear cell tumors, however, showed remarkably similar expression patterns regardless of their origin, even when compared with renal clear cell samples. A set of 43 genes was common to comparisons of each of the three histologic subtypes of ovarian cancer with normal ovarian surface epithelium. CONCLUSIONS: The comparison of the gene expression profiles of endometrioid and serous subtypes of ovarian and endometrial cancer are largely unique to the combination of a particular subtype in a specific organ. In contrast, clear cell cancers show a remarkable similarity in gene expression profiles across organs (including kidney) and could not be statistically distinguished.     

Liver transplantation in children with sickle-cell disease.

Severe liver disease is an unusual but potentially fatal complication of sickle-cell disease (SCD). Liver transplantation has been complicated by ongoing SCD and thrombosis. We reviewed 214 pediatric transplants done at our institution from 1990 to 2005. Three patients were transplanted for complications of SCD, including intrahepatic cholestasis and viral hepatitis. Overall patient and graft survival was 66%. One patient died after 6 years from a subdural hematoma. There were not any incidences of graft loss, primary nonfunction, or thrombosis. All 3 patients required between 1 and 4 postoperative transfusions to keep hemoglobin (Hgb) >9 g/dL with an S fraction of less than 25%. One patient required a preoperative transfusion for a hemoglobin S (HbS) fraction of 30%. Mean follow-up has been 4.2 years (range, 2.6-5.4 years). All 3 children continued to suffer sequelae from their SCD. One child suffered from recurrent sickle-cell hepatopathy and chronic graft failure. In conclusion, children with SCD can in rare instances develop acute and chronic liver failure. These children can be successfully transplanted with good outcomes. Careful attention must be paid to HbS fraction and hemoglobin level to prevent sickling and vascular thrombosis. Unfortunately, liver transplant cannot alter the natural course of the disease.     

The measurement of preoperative anxiety.

Preoperative anxiety was assessed using the hospital anxiety and depression (HAD) scale, multiple affect adjective check list (MAACL) and linear analogue anxiety scale (LAAS) in 100 consecutive day case patients undergoing termination of pregnancy. The HAD scale, a recently introduced self assessment scale comprising 7 multiple choice questions, was readily accepted and easily understood by patients. There was a high degree of correlation between the HAD scale and both the MAACL (correlation coefficient 0.74) and the LAAS (correlation coefficient 0.67). There was only a moderate degree of correlation between the HAD scale and the anaesthetist's assessment of anxiety (correlation coefficient 0.46). The HAD scale is a useful method of subjective measurement of preoperative anxiety.