Reactions of the four diastereomeric 16-amino-17-hydroxy-3-methoxy-estra-1,3,5(10)-trienes with aromatic ortho-hydroxy and heteroaromatic alpha-aldehydes and with 1, 3-dicarbonyl compounds-molecular structures of condensation products and of copper(II) complexes.

Vicinal amino alcohols of steroids have been used as starting materials for the synthesis of chiral ligands with defined arrangements of functional groups. Condensation of the four diastereomeric 16,17-steroid amino alcohols 1a-1d with aromatic o-hydroxy and heteroaromatic alpha-aldehydes afforded the Schiff bases 2-6. When the 16,17-substituted compounds 2d, 5d, 6a, and 6d were in solution, the isomeric oxazolidines were detectable by (1)H NMR spectroscopy. The formation of oxazolidines could be avoided by using bulky aldehydes. Reduction of the Schiff bases (also in mixtures with oxazolidines) with NaBH(4) yielded the new N-substituted amino alcohols 12-15. The condensation products of 1a-1d with 1,3-dicarbonyl compounds (7 and 8) exhibited the 1-enamino-3-oxo structure ((1)H NMR spectroscopy). By means of X-ray analysis of 2a-2d, 3d, 7a, and 7c, the torsion angles for the 16N, 17O substituents, which are important for a participation of the 17O substituent in the complexation of metal ions, have been determined. Furthermore, a preferred arrangement between the chelate ring and the steroid plane existed in all investigated condensation products attributable to torsion angles 16H-C16-16N-C of 5-61 degrees. This arrangement was also preserved in the copper(II) complex 11 with 16alpha,17beta-trans configuration of the bidentate steroid ligand and a ratio of 2:1 for ligand: copper in contrast with dimeric copper(II) complexes with a tridentate steroid ligand of 16beta, 17beta-cis configuration (ratio of 1:1 for ligand:copper). The crystal structures of the condensation products are also discussed. In most cases, intermolecular hydrogen bonds between 17-hydroxy groups and the chelate oxygen caused polymeric strands.

Intraurethral sphincter prosthesis to treat hyporeflexic bladders in women: does it work?

OBJECTIVE: To assess the efficacy and safety of a new intraurethral sphincter prosthesis to treat hyporeflexic bladders in women. PATIENTS AND METHODS: Between July 1997 and December 1998, 18 women (mean age 45.8 years, range 26-84) with neurogenic voiding disorders and a hyporeflexic bladder were examined prospectively. All but one patient (who used the Crédé manoeuvre) emptied their bladder using clean intermittent catheterization. The women were fitted with a prosthesis consisting of a valve and a pump inside a short self-retaining silicone device, which was activated by a magnetic remote control unit. The evaluation before implantation comprised a medical history, a neurological evaluation, urodynamic recordings and urine cultures. The follow-up after implantation included a monthly clinical assessment, a symptom questionnaire, urine culture, ultrasonographic examinations and replacement of the device if necessary. Urine samples were also cultured if there was any discomfort or fever. RESULTS: At 16 months of follow-up, only six of 18 patients continued to use the implant (mean follow-up 9.6 months) and were satisfied. In 10 patients major incontinence around the catheter, or irritation, led to removal of the device. Two patients were unable to learn how to transfer to the toilet to empty their bladder; therefore, their implant was removed and they were treated with a suprapubic catheter. Two patients died from unrelated causes. Twelve patients had positive bacteriuria while fitted with the device; six of them became symptomatic. Usually, only symptomatic lower urinary tract infections were treated. Technical problems occurred often; 14 catheters showed technical dysfunction and had to be replaced early and three external remote control units broke for no reason. Despite normal short-term cystoscopic findings (three patients), long-term urethral damage cannot be excluded. Indeed, the six patients who remain fitted with the device already show some widening of their urethra. CONCLUSION: This experience with the new device was disappointing; in eight of the 18 patients incontinence appeared or worsened and led to removal of the device. Technical problems were common. The other concern is that significant long-term urethral damage could be expected, as observed with indwelling catheters over time. Thus, although this device may function for a short period, it is unsuitable for long-term use.

Infertility as the first symptom of male genitourinary tuberculosis.

The diagnosis of male genitourinary tuberculosis is seldom apparent until the disease is far advanced. The earliest clinical symptoms in most cases are epididymitis, dysuria, and hematuria. In the present case, evaluation of a 26-year-old male complaining about primary infertility revealed leukocytospermia and a normal sperm count. The diagnosis of genitourinary tuberculosis was based on positive morning urine culture. Infertility is an uncommon first sign of male genitourinary tuberculosis, but may be a clue to early diagnosis, as demonstrated in the present case.

Determination of kinetic constants for the interaction between a monoclonal antibody and peptides using surface plasmon resonance.

Differences in the affinity of a monoclonal antibody raised against the protein of tobacco mosaic virus for 15 related peptides (residues 134-146) carrying single-residue modifications were investigated using a novel biosensor technology (Pharmacia BIAcore). Analysis of the peptide-antibody interaction in real time allowed fast and reproducible measurements of both association and dissociation rate constants. Out of 15 mutant peptides analyzed, five were not recognized by the antibody at all, and seven were recognized as well as the wild-type peptide. For three of the peptides, the rate constants were different for the mutant and wild-type peptides. The pattern of residue recognition suggests that the epitope is formed by three residues (140, 143, and 144) in a helical conformation that mimics the structure in the protein. Even a minor modification of these residues totally abolishes recognition by the antibody. Modifications of adjacent residues result in small but significant differences in association and/or dissociation rate constants. One of the recognized residues is totally buried in the three-dimensional structure of TMV protein, suggesting that a structural rearrangement next to the helix occurs during protein-antibody interaction.

Cross-reactive potential of monoclonal antibodies raised against proteolysed tobacco etch virus.

Monoclonal antibodies (mAb) capable of reacting with different potyviruses were obtained by immunizing mice with proteolysed tobacco etch virus. The mAb were not equally effective in all ELISA formats and some were specific for different conformational states of the viral coat protein. The mAb also detected antigenic differences between purified virus particles and viral antigen in infected plant sap. In an ELISA format using antigen-coated plates, 5 different potyviruses (out of 7 viruses tested) could be detected in plant sap by one mAb. Different combinations of mAb and polyclonal antiserum could also be used for detecting several potyviruses by ELISA.

Detection of potyviruses with antisera to synthetic peptides.

Eight peptides corresponding to conserved regions of the coat protein of potyviruses were synthesized. All the peptides were recognized by anti-virus or anti-core-virus. Antisera raised to the synthetic peptides were tested with purified viruses and viral antigens present in plant sap. In many cases, the extent of cross-reactivity between different potyviruses was not correlated with the degree of sequence homology between the peptide used for immunization and the corresponding region in the coat protein of the potyvirus tested. An antiserum raised to a peptide of 18 residues containing a highly conserved region was found to react with all seven potyviruses tested.

Mapping of viral epitopes with conformationally specific monoclonal antibodies using biosensor technology.

An automated biosensor system (BIAcore) designed for measuring molecular interactions in real time and without labelling any of the reactants was used for mapping the epitopes of tobacco mosaic virus protein using conformationally specific monoclonal antibodies (MAbs). Some of the MAbs used as capturing antibody on the sensor chip allowed a conformational change to occur in the viral protein. As a result, MAbs specific for the quaternary structure of polymerized viral protein were able to bind to monomeric viral subunits. Compared with classical solid-phase enzyme immunoassay, the biosensor technology possesses several advantages for epitope mapping of viral proteins.

Interaction between viruses and monoclonal antibodies studied by surface plasmon resonance.

An automated biosensor system designed for measuring molecular interactions in real time and without any labelling of the reactants has been used to study the interaction of two animal viruses (vaccinia virus and poliovirus) and two plant viruses (cowpea mosaic virus and tobacco mosaic virus) with monoclonal antibodies. Using monoclonal antibodies specific for different conformational states of viral protein, it was found that the virus particles retained their conformational integrity when immobilized on the dextran matrix present on the sensor chip. Compared to conventional solid phase immunoassays, in which immobilized proteins are usually partly denatured, the biosensor system presents several advantages for studying virus-antibody interaction.

Antigenic cross-reactivity potential of synthetic peptides immobilized on polyethylene rods.

A number of continuous epitopes of tobacco mosaic virus protein (TMVP) have been defined by the pepscan technique using polyclonal and monoclonal antibodies to TMVP as well as antisera raised against synthetic peptides. In general, the location of continuous epitopes agreed with the results of earlier studies with peptides synthesized by classical methods although there were some notable exceptions. Results obtained with the different types of antibodies used in this study indicated that a homology of three residues was sufficient to give rise to antigenic cross-reactions. In the case of antibodies raised against a peptide conjugated to ovalbumin, some unexpected cross-reactivities could be explained by assuming that antibodies to the carrier molecule recognized homologous tripeptide sequences in TMVP and ovalbumin.

Odontoglossum ringspot virus coat protein: sequence and antigenic comparisons with other tobamoviruses.

Comparative immunochemical analysis of different tobamoviruses indicated that the previously reported coat protein sequence of Odontoglossum ringspot virus was likely erroneous. This sequence has been determined again by direct sequencing of the genomic RNA and was found to differ from the previously proposed sequence in 31 of the 157 amino acid residues. The extent of antigenic cross-reactivity between ORSV protein and other tobamovirus proteins was measured by ELISA and found to correlate satisfactorily with the degree of sequence homology.

Venous infarctions.

Strokes of venous origin are relatively infrequent. They usually cause venous infarcts which can be observed in 2 main circumstances: cerebral thrombophlebitis or dural arteriovenous (AV) fistulae draining into cerebral veins. The authors study the CT and angiographic aspects of these venous infarcts and their evolution. Conventional angiography remains indispensable to confirm the diagnosis.

Infared diode laser double-beam spectrometer.

A complete spectrometer for recording high resolution ir absorption spectra with diode lasers is presented. The optical assembly has been adapted to the characteristics of diode lasers but can be used as well with other laser sources. With a double-beam technique variations in laser power are eliminated. Problems of optical alignment and electronic signal detection are discussed, and representative spectra are presented.