Demonstration of a controllable three-dimensional Brownian motor in symmetric potentials.

We demonstrate a Brownian motor, based on cold atoms in optical lattices, where isotropic random fluctuations are rectified in order to induce controlled atomic motion in arbitrary directions. In contrast to earlier demonstrations of ratchet effects, our Brownian motor operates in potentials that are spatially and temporally symmetric, but where spatiotemporal symmetry is broken by a phase shift between the potentials and asymmetric transfer rates between them. The Brownian motor is demonstrated in three dimensions and the noise-induced drift is controllable in our system.

A 10-year follow-up after Kegel pelvic floor muscle exercises for genuine stress incontinence.

OBJECTIVE: To determine the outcome 10 years after an individual course of pelvic floor muscle (PFM) exercises for genuine stress incontinence. PATIENTS AND METHODS: Postal questionnaires were sent to 52 women who had undergone PFM training 10 years earlier, and their medical files were reviewed. The main outcome measures were the patients' self-assessment of therapy outcome, the frequency of PFM exercises at home, and the demand for surgery after physiotherapy. RESULTS: Forty-five women (87%; mean age 61 years) were suitable for analysis. On completing the course of PFM exercises, physiotherapy had been apparently successful in 24 (53%), and considered to have failed in 21 women (47%). Sixteen of the 24 successful patients remained satisfied with their urinary continence when reassessed 10 years later; two women had undergone surgery (8%). In the group where physiotherapy initially failed, five women (24%) who had not had surgery claimed to be much improved; 13 women (62%) had undergone surgery. Overall, women in whom the conservative treatment of stress incontinence had produced an improvement over the 10 years had practised PFM exercises more regularly (76%) than the others (55%; not significant). However, an active voluntary PFM contraction before a sudden intra-abdominal pressure rise ('perineal lock') appeared to be responsible for most of the success. CONCLUSIONS: When PFM training is initially successful, there is a 66% chance that the favourable results will persist for at least 10 years.

Pelvic floor exercises versus vaginal weight cones in genuine stress incontinence.

OBJECTIVE: To compare pelvic floor exercises and vaginal weight cones in the treatment of genuine stress incontinence. STUDY DESIGN: Randomised controlled trial. METHODS: Sixty ambulatory and fit white women (mean age 56 years) with urinary stress incontinence, treated by a single physiotherapist as outpatients during twelve weeks. Thirty women were allocated to a weekly session of pelvic floor exercises. Thirty were allocated to using cones, they were seen every two weeks. OUTCOME MEASURES: Objective: stress test, vaginal squeezing capacity. Subjective: urinary diary, visual analogue scales. RESULTS: Characteristics of both study groups were comparable. Unfortunately, there was an early withdrawal of fourteen (47%) women in the group treated with cones, and none in the other group. Therefore the pelvic floor exercise group was compared not only with the group intended to be treated with cones, but also with the selected group that only received cone therapy. No statistically significantly differences in outcome measures were found between the groups: 53% in the group assigned to pelvic floor exercises and 57% into the group assigned to cones, of which 50% in the group actually treated with cones, considered themselves as cured or improved to a significant degree. Long-term follow-up was not possible as all cone users refused continued exercises with cones once the twelve weeks had ended. CONCLUSION: Pelvic floor exercises and cones are equally effective in the treatment of genuine stress incontinence. Cones are cost and time saving. However, the low patient compliance with the cones importantly limits its clinical applicability, especially in the long run. Therefore, we do not recommend the use of cones.

Pelvic floor muscle exercises in genuine urinary stress incontinence.

Pelvic floor muscle exercises, in the treatment of genuine stress incontinence, have been used successfully since 1948. One may expect a significant improvement (warranting no further therapy), or cure rate of about 50%. These exercises have a long-lasting effect. Poorly motivated women should be discouraged to follow exercise sessions. An active co-operation between urogynecologist, physiotherapist and the patient is important in order to avoid undertreated and dissatisfied women. The option to be operated upon must be easily available.

Pelvic floor muscle exercises: 5 years later.

OBJECTIVES: To determine the outcome of pelvic floor muscle exercises for genuine stress incontinence after 5 years. METHODS: Questionnaires were sent to 48 women, mean age 57 years, with troublesome stress incontinence treated as outpatients by a skilled female physiotherapist to elucidate a self-assessment of therapy outcome and to determine patients' compliance concerning fulfillment of home exercises and attitude toward physiotherapy. Patients' self-assessment responses indicated cured, much improved, some improvement, or unchanged/worse and incidence of anti-incontinence surgery after physiotherapy. RESULTS: The overall cure/much improvement rate for physiotherapy at the end of therapy was 54% and 5 years later it was 58% (confidence interval, 43 to 72); (P = 1.000, binomial test). Thirteen women (27%) underwent surgery. Seven unoperated women (15%) showed only some improvement or relapse and may have been undertreated. Severity of symptoms before therapy was an important factor in therapy outcome but not in therapy maintenance. Frequency of home practicing was comparable in those who had surgery afterward and those who had not. There was no clear linear relationship in long-term effect and frequency of home practicing. Severity of symptoms and behavioral changes bias this relationship. Physiotherapy was well tolerated, as 73% would still prefer it as first choice. Pelvic floor muscle exercises were recommended to friends or relatives by 77% of the patients. CONCLUSIONS: Once a certain level of incontinence is established with pelvic floor muscle exercises, that level is maintained over 5 years.

Pelvic physiotherapy in genuine stress incontinence.

In a prospective cohort study, the effect of pelvic physiotherapy on genuine stress incontinence, factors that influence therapy outcome, and patients' attitudes toward physiotherapy were studied. The study group consisted of 52 ambulatory and mentally fit Caucasian women (mean age, 53 years), suffering from genuine stress incontinence and who had no contraindications for surgery. They had physiotherapy twice weekly for ten weeks. The aim of physiotherapy was strengthening the pelvic floor muscles under control of digital vaginal palpation. Therapy outcome was assessed by a questionnaire and by the patients' self-monitoring urinary diary recording pad changes (52) and number of leakage episodes (35) before treatment and at end of therapy. The questionnaire also served to determine how patients appreciated physiotherapy. Physiotherapy had a low cure rate (+/- 25%) but a high improvement rate causing a decreased demand for surgery. At follow-up (mean 14 months) its beneficial effect was maintained. To date, only 10 patients (19%) have undergone surgery. Severity of symptoms was the only limiting factor. We conclude that every woman with urinary stress incontinence is a potential candidate for physiotherapy but surgical treatment as an option must remain open. Overall, physiotherapy was well accepted since episodes of urinary incontinence were less frequent and therefore bearable; however, changes in patients' behavior play a role.

Properties of dissociatively extracted fetal tooth matrix proteins. I. Principal molecular species in developing bovine enamel.

A sequential dissociative extraction scheme is described in which tooth matrix proteins are extracted first in 4 M guanidine HCl, pH 7.4, and then in 4 M guanidine HCl, 0.5 M EDTA, pH 7.4, both with protease inhibitors present. The latter step dissolves the mineralized portion of the tissue and extracts noncollagenous proteins closely associated with hydroxyapatite crystallites in the mineralized matrix. In fetal bovine enamel, the initial dissociative extraction step completely removes proline-rich amelogenins from the tissue without dissolving the enamel apatite. The amelogenin proteins consist of several species on polyacrylamide gel electrophoresis with sodium dodecyl sulfate, but display anomalous migration behavior relative to conventional marker proteins in this technique. Subsequent extraction of fetal bovine enamel with guanidine HCl/EDTA removes matrix enamelins, acidic glycoproteins that are tightly bound to the enamel hydroxyapatite. This latter fetal protein type has not been isolated previously. The enamelins are adsorbed strongly by DEAE-cellulose in 7 M urea and totally adsorb to synthetic apatite, even in 4 M guanidine HCl. The enamelins display normal behavior on polyacrylamide gels and stain positively for sialic acid/phosphate and carbohydrate. With advancing tooth maturation, amelogenins disappear while enamelins are conserved. Gel filtration chromatography in 4 M guanidine HCl showed amelogenin components at apparent molecular weights of approximately 25,000, 15,000, 9,500, 7,500, and 6,000, while the enamelins eluted at Mr positions of approximately 72,000, 56,000, 42,000, 30,000, 21,000, 13,000, and 8,000. The gel filtration data showed a clear shift in molecular size population from higher to lower components for both amelogenins and enamelins with progressive enamel maturation.

Calcium fluoride containing granules produced in vitro in rat bones.

Femurs and tibias of normal rats were fixed in 4% unbuffered solutions of glutaraldehyde or formaldehyde containing 1% NaF. Following washing, radiographically controlled demineralization was performed in 3.25% HNO3. Light microscopy and transmission electron microscopy revealed the presence of so-called fluoride granules in bone trabeculae, cartilage, cartilage remnants, bone cells, chondrocytes and in the bone marrow. Selected area diffraction indicated that the fluoride granules contained CaF2. X-ray diffraction analysis of non-demineralized NaF-fixed bones were negative for CaF2. The results are discussed and related to precipitation artifacts reported in demineralized hard tissues and to similar CaF2-containing granules observed in demineralized bones and incisors of rats given high doses of NaF in diet or drinking water.

Matrix-mineral relationships--a morphologist's viewpoint.

The literature on the ultrastructural morphology of the enamel matrix and its relationship to the crystals is reviewed. Two morphological entities of the matrix are discussed. One is the so-called stippled material which may be the initial cell product; the other, variously described as fibrillar, lamellar, tubular or helical, is thought by many to play a crucial role in nucleation and orientation of the crystals. A number of observations, however, suggest that the latter structures form secondarily to the crystals and that in reality they represent organic material adsorbed to the crystal surface and maintained as independent structures upon removal of the mineral. The need for additional studies is stressed including systematic studies of interactions between constituents of the organic matrix and the apatite crystals.

Dose and age dependent variations in effect of tetracycline on enamel formation in rat.

Incidence of rats with gross enamel lesions in response to tetracycline hydrochloride (TC) was studied in relationship to age, tooth type, and concentration of antibiotic in the injection fluid. Incidence was defined as percentage of animals with defects in at least one incisor or one molar. Serum levels were measured at various intervals in 4- and 75-day-old rats, which received a single i.p. injection with 130 mg/kg bw in concentrations of either 13 or 25 mg/ml saline. The study confirmed that the effect of TC on enamel varied with age of the animal and that the molar responded more readily than the incisor. Furthermore, the incidence was higher the higher the concentration of antibiotic. This effect appeared tied to a direct relationship between concentration and serum level. Serum levels declined more slowly in the younger than in the older rats, resulting in significantly higher levels 6, 24 and 48 h after dosing, which correlated with a more extensive labeling of the dentin in the young rats. The possible roles of serum levels, capillary supply and cell susceptibility are discussed in relation to differences in response with animal age, between tooth types, tooth surfaces and with age of the secretory cells.