Linkage mapping of fifty-eight new rat microsatellite markers

Fifty-eight new anonymous simple sequence repeats (SSR) were generated and mapped to various rat chromosomes. Among them two genes (rat homologs for human cadherin-14 and mouse fibroblast growth factor-related protein) were mapped on Chromosomes (Chrs) 2 and 11 respectively. The majority of markers were generated from a small insert genomic library specific to Chr 11, 13, 14, and 15. Twenty new markers were mapped to Chr 13, which is known to contain a blood pressure quantitative trait locus (QTL). Several approaches to obtain microsatellite markers are described. The protocols and newly generated markers should be useful for ongoing rat genome project.     

Monocyte procoagulant activity induced by adherence to an artificial surface is reduced by end-point immobilized heparin-coating of the surface

Heparin-coating improves the biocompatibility of blood contacting artificial surfaces. This led us to investigate the impact of heparin-coating (Carmeda AB, Stockholm) of polymetylmetacrylate on the expression of monocyte tissue factor procoagulant activity (TF-PCA) by surface adhesion. Also, the anticoagulant effect of heparin-coating in the presence or absence of adherent procoagulant monocytes was assessed. This is of particular interest, since activation of extrinsic coagulation by adherent monocyte TF-PCA may play a significant role in thrombin generation during extracorporeal circulation. Monocytes exposed to heparin-coated or non-coated polymetylmetacrylate expressed TF-PCA. The heparin coat did not affect the rate of monocyte adhesion. However, heparin-coating reduced the induction of TF-PCA of non-adherent and adherent monocytes by 17 and 33% (p <0.001 and p <0.0003), respectively. Heparin-coating in the absence of monocytes, totally inhibited the clotting of recalcified plasma (p <0.003). In contrast, in the presence of adherent monocytes expressing TF-PCA, surface-bound heparin did not inhibit clotting. However, inclusion of heparin in a plasma concentration of 8.9 IU/ml totally inhibited the activation of coagulation. It is apparent that heparin-coating of an artificial surface is an efficient means to inhibit coagulation of recalcified plasma, but much less so when procoagulant monocytes are adherent to the coated surface. The present findings are of clinical relevance, since monocytes will adhere to blood contacting surfaces of extracorporeal circuits or to implanted vascular prostheses and subsequently express TF-PCA, and this may promote thromboembolism.     

Percutaneous iliosacral screw placement using image guided techniques

A computer assisted technique of iliosacral screw placement that is applicable to unstable pelvic ring fractures is proposed. The goals are to operate noninvasively with a percutaneous procedure to decrease the complications of surgical exposure and to provide greater accuracy in locating the close neurovascular structures. Preoperative computed tomographic images of the pelvis are provided and a computed tomography three-dimensional model is built. In this model, the optimal trajectories for the drilling are planned. An ultrasound based registration is performed intraoperatively. This registration is the most original part of this work. After performing the passive drilling guidance step, the surgeon places the screws. The accuracy of the ultrasound based registration is checked by comparison with a standard surface based registration at the end of the test experiment. Each screw position is verified by a computed tomographic examination. Four human anatomic specimen pelves were tested with three screw insertions for each pelvis (12 screws). All of the screws were considered to be placed correctly. The method is safe and encourages the start of clinical application.     

Altered hippocampal kainate-receptor mRNA levels in temporal lobe epilepsy patients

This study determined whether hippocampal kainate (KA) receptor mRNA levels were increased or decreased in temporal lobe epilepsy patients compared with nonseizure autopsies. Hippocampal sclerosis (HS; n = 17), nonsclerosis (non-HS; n = 11), and autopsy hippocampi (n = 9) were studied for KA1-2 and GluR5-7 mRNA levels using semiquantitative in situ hybridization techniques, along with neuron densities. Compared with autopsy hippocampi, HS and non-HS cases showed decreased GluR5 and GluR6 hybridization densities per CA2 and/or CA3 pyramid. Furthermore, HS patients demonstrated increased KA2 and GluR5 hybridization densities per granule cell compared with autopsy hippocampi. These findings indicate that chronic temporal lobe seizures were associated with differential changes in hippocampal KA1-2 and GluR5-7 hybridization densities that vary by subfield and pathology group. In temporal lobe epilepsy patients, these results support the hypothesis that pyramidal cell GluR5 and GluR6 mRNA levels are decreased as a consequence of seizures, and in HS patients granule cell KA2 and GluR5 mRNA levels are increased in association with aberrant fascia dentata mossy fiber sprouting and/or hippocampal neuronal loss.     

Native valve infective endocarditis in elderly and younger adult patients: comparison of clinical features and outcomes with use of the Duke criteria and the Duke Endocarditis Database

The effect of age on the presentation and outcome of infective endocarditis (IE) is unclear. Many of the available data are based on analyses of mixed populations of patients including intravenous drug users or those with prosthetic valve endocarditis or native valve IE. We used the Duke criteria to compare the characteristics of 44 episodes of definite native valve IE in elderly patients (> 64 years old) with the characteristics of 64 similarly defined episodes of native valve IE in younger, nonintravenous-drug-using adult patients (> 29 years and < 60 years old). Our data suggest that the clinical presentation, characteristics, and outcome of native valve IE are similar for elderly patients and younger adult patients, although elderly patients were hospitalized an average of 12 days longer. Although we found that the occurrence of renal failure and cerebral embolism during an episode of IE was associated with higher rates of death (odds ratios, 4.8 and 4.0, respectively), age was not a significant contributor to mortality.     

Patterns of messenger RNA expression for alpha1-adrenoceptor subtypes in human corpus cavernosum

PURPOSE: The present study evaluated the expression of alpha1-adrenoceptor subtypes in human corpus cavernosum. MATERIALS AND METHODS: The mRNA encoding alpha1a, alpha1b and alpha1d subtypes were assessed by RNA-directed complementary cDNA synthesis followed by Taq DNA amplification. The level of alpha1 mRNA was calculated in arbitrary optical density units and normalized with respect to the length of the respective cDNA fragments. RESULTS: We found that alpha1a, alpha1b and alpha1d adrenoceptor subtypes are expressed in human corpus cavernosum, with a predominant expression of the alpha1a subtype. CONCLUSION: These results suggest that alpha1a-adrenoceptor subtype is important and that understanding the biochemical and functional characteristics of this subtype may lead to the development of specific antagonists in the treatment of impotence.     

On the mechanism of human stefin B folding: II. Folding from GuHCl unfolded, TFE denatured, acid denatured, and acid intermediate states

In this report, we demonstrate the utility of interleukin-2 (IL-2) stimulation of spleen cell cultures and bivariate flow cytometry in the analysis and purification of the C57BL/6J mouse Y Chromosome. We determined that the DNA content of the C57BL/6J Y Chromosome is approximately 94.7 Mb, making it similar in size to human Chromosome 16 and significantly larger than previous estimates. In addition, we describe the bulk isolation of mouse Y Chromosomes and demonstrate enrichment of the isolated material using a fluorescence in situ hybridization strategy. We detail the construction of two small insert Y Chromosome-specific libraries, ideal for sampling Y Chromosome sequences. From these libraries 1566 clones were analyzed. We provide a detailed characterization of 103 clones, generating nearly 50 kb of sequence. For 30 of these clones, we identify regions of homology to known Y chromosomal sequences, confirming the enrichment of the sorted DNA. From the remaining characterized clones, we describe the development of 15 male-specific PCR assays and 19 male-female PCR assays potentially originating from the pseudoautosomal region or other areas of X-Y or autosome-Y homology.