Interrelationships of clinical outcome, length of resection, and energy cost of walking after prosthetic knee replacement following resection of a malignant tumor of the distal aspect of the femur

An automated method for analysis of in vivo proton magnetic resonance (MR) spectra and reconstruction of metabolite distributions from MR spectroscopic imaging (MRSI) data is described. A parametric spectral model using acquisition specific, a priori information is combined with a wavelet-based, nonparametric characterization of baseline signals. For image reconstruction, the initial fit estimates were additionally modified according to a priori spatial constraints. The automated fitting procedure was applied to four different examples of MRS data obtained at 1.5 T and 4.1 T. For analysis of major metabolites at medium TE values, the method was shown to perform reliably even in the presence of large baseline signals and relatively poor signal-to-noise ratios typical of in vivo proton MRSI. Identification of additional metabolites was also demonstrated for short TE data. Automated formation of metabolite images will greatly facilitate and expand the clinical applications of MR spectroscopic imaging.     

Decision making in detecting abnormal Semmes-Weinstein monofilament thresholds in carpal tunnel syndrome

Both hands of 39 patients who had symptoms of pain and/or numbness in one or both hands were tested by two hand therapists using the full kit of Semmes-Weinstein monofilaments (SWMFs). The SWMF thresholds were obtained for the thumb, the index finger, and the long and small fingers. These thresholds were classified as normal or abnormal based on four decision rules and two criterion measures. Decision rules were based on whether SWMF 2.83 or 3.22 would be the best limit of normality, and whether the small finger should be used for within-subject comparisons. The criterion measures were the highest threshold of all three radial digits and the highest threshold of the long finger alone. Intertherapist agreement on normality was fair to moderate (kappa = 0.22-0.51), varying according to decision rules and criterion measures. Reliability was higher when the additional comparison with the small finger was omitted. High accuracy in identifying cases of carpal tunnel syndrome (CTS) was possible, but accuracy varied moderately between testers and greatly according to decision rules and criterion measurements. The best overall accuracy (81%-82% sensitivity and 57%-86% specificity) was achieved when SWMF 2.83 was used as the upper limit of normality and the small finger was used for within-subject comparison, and when data from the long finger alone were used for decision making.     

Disinfection and sterilization of reusable devices]

Official of quality assurance requirements for the disinfection and sterilization of reusable medical devices in health care facilities has been reminded recently. These requirements concern good manufacturing practices, essential to avoid adverse events. Identification of non critical and invasive devices, protocols for pre-disinfection, cleaning, high level disinfection and sterilization for thermosensitive materials must be evaluated. Monitoring and process control of these operations are defined by French regulations and European standards, and every health professional has to become aware of these limits.     

Development of a microassay for estradiol receptors

The calculation of equilibrium binding constants for a specific receptor-hormone interaction requires the exact determination of the unbound ligand concentration and the specifically bound concentration at equilibrium. These determinations usually require corrections for the contribution of non-specific binding. We introduce several parameters allowing equilibrium concentrations to be calculated from experimental concentration values; these parameters can be measured for the particular receptor assay procedure used. These parameters are used in a microassay of estradiol-receptor complex by selective retention on DE-81 cellulose paper.     

Deletion of the central proline-rich repeat domain results in altered antigenicity and lack of surface expression of the Streptococcus mutans P1 adhesin molecule

Members of the family of surface adhesins of oral streptococci, including P1 of Streptococcus mutans, contain two highly conserved repeat domains, one rich in alanine (A region) and the other rich in proline (P region). To assess the contribution of the P region to the biological properties of P1, an internal deletion in spaP was engineered. In addition, the P region was subcloned and expressed as a fusion partner with the maltose binding protein of Escherichia coli and liberated by digestion with factor Xa. Results of Western blot experiments in which recombinant polypeptides were probed with a panel of 11 monoclonal antibodies indicated that the P region is a necessary component of conformational epitopes within the central portion of P1. Antibodies reactive with the P region were detected in a polyclonal rabbit antiserum generated against whole S. mutans cells but not in two rabbit antisera generated against purified P1 (Mr approximately 185,000), suggesting that this domain is immunogenic on the surface of intact bacteria but not as part of a soluble full-length molecule. Finally, transformation of a spaP-negative mutant with a shuttle vector containing an internally deleted spaP lacking P-region DNA resulted in a complete absence of surface-localized P1 and substantially less P1 in sonicated cells compared to the case for the mutant complemented with the full-length gene. These results suggest that the P region is an integral component contributing to the conformation of the central region of P1 and indicate that its presence is necessary for surface expression of the molecule on S. mutans.     

5-hydroxytryptamine1A receptor-mediated effects on adenylate cyclase and nitric oxide synthase activities in rat ventral prostate

AIM: To investigate the patterns of expression of transforming growth factor alpha (TGF-alpha) and epidermal growth factor receptor (EGFR) in squamous metaplasia and squamous cell carcinomas of the urinary bladder with and without schistosomiasis. METHODS: Immunohistochemical study of the expression of TGF-alpha and EGFR in squamous metaplasias (n = 12) and various grades of squamous cell carcinomas (n = 21) of the bladder with and without schistosomiasis. RESULTS: Focal cytoplasmic and membranous positivity for EGFR and TGF-alpha was seen in all cases of squamous metaplasia. The markers were diffusely coexpressed in a concordant pattern in areas of hyperplastic keratinising squamous metaplasia. A similar pattern of positivity was seen in verrucous carcinomas (n = 2) and well differentiated squamous carcinomas (n = 6). Progressive loss of differentiation was associated with increasing loss of EGFR staining while TGF-alpha staining was retained. Squamous cell carcinoma in situ (n = 2) showed focal positivity for TGF-alpha and EGFR. There were no differences in staining patterns between cases with and without schistosomiasis. CONCLUSIONS: The coexpression of TGF-alpha and EGFR by well differentiated squamous cell carcinomas and hyperplastic keratinising squamous metaplasia is consistent with the active regulatory role exerted by this autocrine loop. There is regional absence of expression of EGFR but not of TGF-alpha in squamous cell carcinomas of lesser differentiation, suggesting heterogeneity of such control in these tumours. The focal expression of the two markers in squamous cell carcinomas in situ indicates a possible second pathway of oncogenesis for less differentiated tumours. These observations may have important implications for the effectiveness of putative growth factor based treatments.