Micrometer-sized fibrillar protein aggregates from soy glycinin and soy protein isolate.

Long, fibrillar semiflexible aggregates were formed from soy glycinin and soy protein isolate (SPI) when heated at 85 degrees C and pH 2. Transmission electron microscopy analysis showed that the contour length of the fibrils was approximately 1 microm, the persistence length 2.3 microm, and the thickness a few nanometers. Fibrils formed from SPI were more branched than the fibrils of soy glycinin. Binding of the fluorescent dye Thioflavin T to the fibrils showed that beta-sheets were present in the fibrils. The presence of the fibrils resulted in an increase in viscosity and shear thinning behavior. Flow-induced birefringence measurements showed that the behavior of the fibrils under flow can be described by scaling relations derived for rodlike macromolecules. The fibril formation could be influenced by the protein concentration and heating time. Most properties of soy glycinin fibrils are comparable to beta-lactoglobulin fibrils.

Investigating the permanent electric dipole moment of beta-lactoglobulin fibrils, using transient electric birefringence.

Amyloid fibrils, which are polymeric assemblies of protein molecules, have been intensively studied on a structural level, yet due to complications such as the disorder within the molecules, several aspects of their structure remain mysterious. Similarly, the kinetics of assembly are not well understood. Here we investigate the electric dipole moment of beta-lactoglobulin fibrils, a model amyloid fibril system, by applying the technique of transient electric birefringence. This moment appears to be large, and comparable to the total moment of the constituent protein monomers if they were joined in a chain, head-to-tail, without changing conformation, suggesting an ordered joining of monomers in the fibril. Such an ordered assembly may have implications for the assembly mechanism of beta-lactoglobulin fibrils in particular, and amyloid fibrils in general.

Electric birefringence study of an amyloid fibril system: the short end of the length distribution.

In this article, a system of amyloid fibrils, based on the protein beta-lactoglobulin, is studied by transient electric birefringence. Single pulses of an electric field were applied to the solution, and the initial rise and subsequent decay of birefringence analysed. The decay takes place on a range of relaxation times, and therefore contains information about the length distribution of fibrils in the system. The information can be extracted using theories of the electric polarisability of polyelectrolyte rods, since the fibrils are an example of these. Despite the long-standing complications of such theories, useful quantitative information about the system can still be obtained. Using the Fixman model of polyelectrolyte polarisability, we obtain a measurement of the short end of the length distribution which shows the fibril concentration as a function of length rising linearly from 0.02-2 microm. The short end of the length distribution was unobtainable in our previous study using rheo-optics (S.S. Rogers et al., Macromolecules 38, 2948 (2005)), but reasonable agreement between the two techniques shows they are complementary.

Functional extracorporeal magnetic stimulation as a treatment for female urinary incontinence: 'the chair'.

OBJECTIVE: To evaluate, in a prospective study, the efficiency and applicability of functional magnetic stimulation (FMS) of the pelvic floor for treating urinary incontinence in women. PATIENTS AND METHODS: FMS was provided by a 'magnetic chair'; 24 patients were treated twice weekly for 8 weeks (12 with urge incontinence and 12 with a mixture of urge and stress incontinence). The outcome was assessed urodynamically, by a pad test, and by patient satisfaction. RESULTS: In 58% of the patients there was an objective improvement in incontinence; three patients were completely dry and 71% reported a subjective improvement (P < 0.001). CONCLUSION: FMS is a safe, noninvasive and painless treatment for urinary incontinence; it is effective and easy to administer as an outpatient treatment.

Methods to improve efficacy of intravesical mitomycin C: results of a randomized phase III trial.

BACKGROUND: Intravesical chemotherapy (i.e., placement of the drug directly in the bladder) with mitomycin C is beneficial for patients with superficial bladder cancer who are at high risk of recurrence, but standard therapy is empirically based and patient response rates have been variable, in part because of inadequate drug delivery. We carried out a prospective, two-arm, randomized, multi-institutional phase III trial to test whether enhancing the drug's concentration in urine would improve its efficacy. METHODS: Patients with histologically proven transitional cell carcinoma and at high risk for recurrence were eligible for the trial. Patients in the optimized-treatment arm (n = 119) received a 40-mg dose of mitomycin C, pharmacokinetic manipulations to increase drug concentration by decreasing urine volume, and urine alkalinization to stabilize the drug. Patients in the standard-treatment arm (n = 111) received a 20-mg dose without pharmacokinetic manipulations or urine alkalinization. Both treatments were given weekly for 6 weeks. Primary endpoints were recurrence and time to recurrence. Treatment outcome was examined by use of Kaplan-Meier analysis with log-rank tests. Statistical tests were two-sided. RESULTS: Patients in the two arms did not differ in demographics or history of intravesical therapy. Dysuria occurred more frequently in the optimized arm but did not lead to more frequent treatment termination. In an intent-to-treat analysis, patients in the optimized arm showed a longer median time to recurrence (29.1 months; 95% confidence interval [CI] = 14.0 to 44.2 months) and a greater recurrence-free fraction (41.0%; 95% CI = 30.9% to 51.1%) at 5 years than patients in the standard arm (11.8 months; 95% CI = 7.2 to 16.4 months) and 24.6% (95% CI = 14.9% to 34.3%) (P =.005, log-rank test for time to recurrence). Improvements were found in all risk groups defined by tumor stage, grade, focality, and recurrence. CONCLUSIONS: This study identified a pharmacologically optimized intravesical mitomycin C treatment with statistically significantly enhanced efficacy.

[Acute urinary retention in women]. / Acute urineretentie bij vrouwen.

Acute urinary retention in women is not a common problem. The incidence is 0.07 per 1000 inhabitants per year. The causes of acute urinary retention can be divided into four groups: obstructive, neurological, pharmacological and psychogenic. More than half of acute urinary retentions occur after surgery or parturition. The most common obstructive cause is a gynaecologic tumor. A psychogenic cause is a diagnosis per exclusionem. The treatment of the acute urinary retention has to be catheterisation before further investigation is done.

[Inventory and follow-up of patients with surgery for (uterine) vaginal prolapse, combined with or without, (masked) stress incontinence]. / Inventarisatie en follow-up van patiënten, geopereerd vanwege (utero) vaginale prolaps, al dan niet gecombineerd met (gemaskeerde) stressincontinentie.

OBJECTIVE: Evaluation of the development or persistence of urinary stress incontinence in patients operated on because of prolapsed uterus, with cooperation between gynaecologists and urologists. DESIGN: Retrospective. SETTING: Department of Gynaecology and Obstetrics, Leyenburg Hospital, The Hague, the Netherlands. METHODS: In 178 patients subjected to prolapse correction in the period 1992-1996, presence of urinary incontinence was analysed by means of a written enquiry after an average of 22 months. The 91 patients who had visited the gynaecological outpatient clinic and were seen together with a urologist, were subjected to urodynamic examination in the absence of symptoms of stress incontinence and were operated in cooperation with the urologist. Four groups were distinguished on the basis of preoperative features: group I (n = 37) with manifest stress incontinence, group II (n = 22) with masked stress incontinence, group III (n = 32) in whom no (masked) stress incontinence could be demonstrated and group IV (n = 87) not subjected to urodynamic examination. The patients of groups I and II, in addition to prolapse correction, were also subjected to urethral suspension. RESULTS: Twenty-five (68%) of the group with manifest stress incontinence were free of stress incontinence after the operation, while eight patients (22%) reported improvement (a total of 89%). In 22 of the 54 patients (41%) who preoperatively had no incontinence symptoms, urodynamic examination revealed a masked stress incontinence. Sixteen of them (73%) did not develop symptoms of stress incontinence after the operation, while eight (15%) did develop such symptoms. Thirty of the 32 patients (94%) who preoperatively had no (masked) stress incontinence remained symptom-free. Out of 64 patients without preoperative incontinence, who were operated without urological cooperation, 12 (19%) developed stress incontinence.

Interaction of Cadmium with Phosphate on Goethite

Interactions between different ions are of importance in understanding chemical processes in natural systems. In this study simultaneous adsorption of phosphate and cadmium on goethite is studied in detail. The charge distribution (CD)-multisite complexation (MUSIC) model has been successful in describing extended data sets of cadmium adsorption and phosphate adsorption on goethite. In this study, the parameters of this model for these two data sets were combined to describe a new data set of simultaneous adsorption of cadmium and phosphate on goethite. Attention is focused on the surface speciation of cadmium. With the extra information that can be obtained from the interaction experiments, the cadmium adsorption model is refined. For a perfect description of the data, the singly coordinated surface groups at the 110 face of goethite were assumed to form both monodentate and bidentate surface species with cadmium. The CD-MUSIC model is able to describe data sets of both simultaneous and single adsorption of cadmium and phosphate with the same parameters. The model calculations confirmed the idea that only singly coordinated surface groups are reactive for specific ion binding.

Intrinsic Proton Affinity of Reactive Surface Groups of Metal (Hydr)oxides: The Bond Valence Principle

The proton affinity of individual surface groups has been calculated with a redefined version of the multi site complexation (MUSIC) model. In the new approach the proton affinity of an oxygen originates from the undersaturation of the oxygen valence. The factors valence and coordination number, which are the basis of Pauling's definition of bond valence, in combination with the number of coordinating (Me and H) ions, are dominant in determining the proton affinity. The neutralization of an oxygen by Me ion(s) is calculated on the basis of the actual bond valence, which accounts for structural details, resulting from an asymmetrical distribution of charge in the coordination environment. An important role in the new version of the MUSIC model is given to the H bonds. The model shows that the proton affinity is determined not only by the number of donating H bonds but also by the number of accepting H bonds. The proton affinity of surface groups and of solution complexes can be understood in one theoretical framework, on the basis of a different number of donating and accepting H bonds. The MUSIC model predicts the variation in proton affinity constants for surface groups in particular those with the same number of coordinating Me ions but with a different structural position. The model is able to predict on the basis of the proton affinity of the individual groups the correct PZC of Me hydroxides, oxohydroxides, and oxides, and explains previous exceptions. The model can also be applied in general to other minerals.

Multisite Adsorption of Cadmium on Goethite

Recently a new general ion adsorption model has been developed for ion binding to mineral surfaces (Hiemstra and van Riemsdijk, 1996). The model uses the Pauling concept of charge distribution (CD) and is an extension of the multi-site complexation (MUSIC) approach. In the CD-MUSIC model the charge of an adsorbing ion that forms an inner sphere complex is distributed over its ligands, which are present in two different electrostatic planes. In this paper we have applied the CD-MUSIC model to the adsorption of metal cations, using an extended data set for cadmium adsorbing on goethite. The adsorption of cadmium and the cadmium-proton exchange ratio were measured as function of metal ion concentration, pH, and ionic strength. The data could be described well, taking into account the surface heterogeneity resulting from the presence of two different crystal planes (the dominant 110 face and the minor 021 face). The surface species used in the model are consistent with recent EXAFS data. In accordance with the EXAFS results, high-affinity complexes at the 021 face were used in the model.

Isothermic irrigation during transurethral resection of the prostate: effects on peri-operative hypothermia, blood loss, resection time and patient satisfaction.

OBJECTIVES: To investigate the effect using irrigation fluid at body temperature (isothermic) on patients' (core) temperature during a transurethral resection of the prostate (TURP) and on the amount of peri-operative blood loss, the resection time and the subjective assessment of comfort by the patients. PATIENT AND METHODS: In a randomized study, patients undergoing TURP under spinal anaesthesia were divided into those receiving either isothermic irrigation fluid (Group 1.28 patients) or fluid at room temperature (Group 2.31 patients). In Group 1, a fluid heater maintained the irrigation fluid at body temperature until it reached the bladder. The body temperature of the patients was recorded rectally and orally during and after TURP and the peri-operative blood loss was also measured. The patients were interviewed on the first day after TURP to determine their assessment of comfort during the procedure. RESULTS: The decrease in body temperature was 0.74 degree C in Group 1 and 1.71 degrees C in Group 2, which was significantly different (P < 0.001). There was no significant difference in blood loss or resection-time. In Group 1, only four (14%) of the patients were aware that their body was cooler, compared to 15 (50%) in Group 2 (P = 0.038). CONCLUSION: Isothermic irrigation during TURP prevents excessive cooling and reduces the level of hypothermia. The reported increased mortality after TURP is probably related to peri-operative cardiac stress, an important factor which could be caused by the rapid decrease in body temperature which accompanies normal irrigation. Because the heating equipment presently available does not interfere with TURP, there are strong arguments for performing every TURP with irrigation fluid at body temperature.

[A patient with a vesico-uterine fistula]. / Een patiënte met een vesico-uteriene fistel.

In a 20-year-old woman with a uterus didelphys a vesicouterine fistula was diagnosed after caesarean section. The symptoms suggested a vesico-vaginal fistula but no abnormalities could be detected vaginally and the methylene-blue test was negative. The fistula was visualised by instillation of radiopaque contrast fluid into the vesical fistula opening, using a ureter catheter. The patient was operated via a transperitoneal route with interposition of peritoneum between the urinary bladder and the uterus.

The effect of orgasm on prostate-specific antigen.

To identify the effect of orgasm on serum prostate-specific antigen (PSA) levels, a prospective trial before and after orgasm was performed in 14 healthy colleagues aged 32-62 years (mean, 44.4 years) with no evidence of prostatic disease. PSA determinations were performed on serum samples obtained before and after orgasm. Significant changes in PSA levels after orgasm were found (P = 0.002, analysis of variance). We conclude that the impact of orgasm on PSA levels should be taken into account when the latter are used for the detection of prostatic disease.

Treatment of corpus cavernosum abscess by aspiration and intravenous antibiotics.

We report the successful treatment of an abscess in the corpus cavernosum of a paraplegic man on intracavernous papaverine injection therapy by means of percutaneous aspiration and intravenous antibiotics. After 3 months of intracavernous pharmacotherapy the patient experienced good erections again and only minimal fibrosis could be found on palpation.

[Routine intravenous pyelography not diagnostically useful in men with lower urinary tract infections]. / Routinematige intraveneuze pyelografie bij mannen met een lage-urineweginfectie diagnostisch niet zinvol.

OBJECTIVE: Evaluation of intravenous urography (IVU) in men with a lower urinary tract infection. SETTING: Leyenburg Hospital, the Hague, the Netherlands. DESIGN: Retrospective. METHODS: In 28 male patients with a diagnosed lower urinary tract infection, an IVU was made in order to find causative urogenital tract abnormalities. We determined whether the IVU provided additional diagnostic information. RESULTS: Only I IVU (4%) of the 28 showed abnormalities (a bladder stone in a patient with epididymitis). The finding was not statistically significant (Fisher's exact test). CONCLUSION: In men with a symptomatic lower urinary tract infection showing symptoms such as frequent and burning micturition, whether or not complicated or not by epididymitis, an IVU gives no additional diagnostic information.

Bilateral hydronephrosis with urosepsis due to neglected pessary. Case report.

In an 86-year-old woman a neglected pessary and extreme coprostasis gave rise to anuria, urosepsis and bilateral ureteropelvic dilatation with an empty bladder. This seems to be the first reported case of its kind.