Determination of available breaking stress of agar and gellan gum plate culture methods and the duration of bacterial culture under strong acidic conditions.

AIMS: Several acidophilic bacteria have not been cultured, primarily owing to the lack of suitable culture methods under strong acidic conditions. This study aimed to quantitatively evaluate the strengths of the agar plates (AP) and gellan gum plates (GP), and optimal culture periods under strong acidic conditions. METHODS AND RESULTS: To define the lower limit of plate strength for bacterial isolation culture, the diameter of Escherichia coli K12 colonies and the breaking stress of plates at different concentrations of gelling agents, medium composition and pH conditions were determined. The lower limit of available strength of AP and GP was 19·6 and 14·8 kPa, respectively. Medium composition slightly affected AP breaking stress, although GP with a high cationic concentration medium could not be prepared. CONCLUSIONS: Assessment of the strength limits of AP and GP revealed that AP is not suitable for prolonged bacterial culture (≥72 h). Furthermore, GP was completely ineffective for bacterial culture under highly acidic conditions (≤pH 1·0). SIGNIFICANCE AND IMPACT OF THE STUDY: Our quantitative evaluation method based on breaking stress is a potentially valuable tool to understand the state and the suitable limit of plate culture methods in more detail under various conditions.

An in-shoe device to measure plantar pressure during daily human activity.

In this work, we report the development of a novel device, integrated into a shoe, to monitor plantar pressure under real-life conditions by reducing the spatial and temporal resolution. The device consists of a shoe insole with seven pressure-sensitive conductive rubber sensors and a wireless data transmission unit incorporated into a smaller measurement unit. One advantage of this approach is that the mass and volume of the measurement unit are less than 1/10th and 1/50th, respectively, of that reported for other devices. A comparison experiment was conducted for validation of the device using the F-scan system, and the initial test of the device was conducted by recording unobstructed gaits of one young adult subject and two elderly subjects. Each subject performed a straight, level walking trial at a comfortable speed for 7 m without any assistive device while wearing the in-shoe device. Changes in the plantar pressure during gait were recorded. Compared with the young subject, the pressure under the heel of the elderly subject was found to be smaller and less steep. This in-shoe device can be used to monitor plantar pressure during daily living and is expected to be useful in various clinical applications.

Does electrical stimulation of the pelvic floor make any change in urodynamic parameters? When to expect a cure and improvement in women with stress urinary incontinence?

OBJECTIVE: Our study aimed at determining the effects of pelvic floor electrical stimulation assessed by the number of leakages per day recorded in a voiding diary over 90 days of treatment and urodynamic parameters. STUDY DESIGN: This prospective study was carried out with 34 patients presenting stress urinary incontinence who were treated and evaluated by voiding diaries and urodynamic tests. The primary outcome measure was the number of leakages during the 90 days of treatment. Urodynamic tests were performed before and after treatment. RESULTS: In our series, average and maximum flow rates and residual urine volume were within normal range in all subjects before and after treatment. Maximum urethral closure pressure and functional profile length on urethral pressure profiles did not change after treatment. In the cystometry, bladder capacities at the first (p < 0.0082) and maximum sensations (p < 0.01) improved significantly after treatment. During the 90 days of treatment, we observed a gradual drop in the number of leakages. This decrease began around day 22. It dropped in half around day 45, tending to zero close to day 90 of treatment (p < 0.01). CONCLUSIONS: The number of incontinent leakage dropped to half around the 8th week, and on average, there was a tendency of the patients to be cured after the 12th week of treatment. At urodynamic studies we observed a significant increase in bladder capacity at the first desire to void and in the maximum cystometric capacity.

Clinical and urodynamic evaluation of women with detrusor instability before and after functional pelvic floor electrostimulation.

Detrusor instability is the second most frequent cause of female urinary incontinence. There are many therapeutic options, including non-invasive and surgical procedures. In this study, we evaluated the effects of pelvic floor vaginal electrostimulation using equipment designed in our institution, over three consecutive months, for treatment of 29 women with detrusor instability. After treatment 22 patients (76%) considered themselves cured or symptomatically improved; seven patients (24%) had no change in symptoms after therapy. There was objective cure and improvement in ten (34.5%) and in eight (27.5%) patients, respectively, and the urodynamic parameters did not change in 11 patients (38%). Electrical stimulation resulted in a gradual decrease in the number of urinary leakage episodes and increase in maximum cystometric capacity in first desire to void and in urinary volume.

Analysis of collagen in parametrium and vaginal apex of women with and without uterine prolapse.

Our objective was to compare the amount of collagen in parametrium and vaginal apex between women with uterine prolapse at pre- and postmenopause, and in women without prolapse. The study included 22 premenopausal women without prolapse (group A), 10 premenopausal women with prolapse (group B), and 23 postmenopausal women with prolapse (group C) (total 55). Patients in group A underwent abdominal hysterectomy for uterine leiomyoma, and patients in groups B and C underwent vaginal hysterectomy. During the surgical procedure we obtained biopsies from the lateral parametrium and vaginal apex. The tissue was stained for histological analysis with picrosirius. We observed a lower amount of collagen in the parametrium of women with uterine prolapse, both in menacme and in postmenopause, than in the parametrium of women without prolapse. We observed no statistically significant difference in vaginal apex between the groups.

Asymmetrical lipid charge changes the subconducting state of the potassium channel from sarcoplasmic reticulum.

The K+ channel of sarcoplasmic reticulum was incorporated into planar lipid bilayers having various net surface charges. The conductance of both the main-state and substate increased with the increase in negative charges of the membrane and vice versa. The change in the conductance of the substate was larger than that of the main-state. The K+ channel reconstituted into asymmetrical planar lipid bilayers revealed that the effect on the substate was derived from only one half (trans) of the bilayer. The substate of the K+ channel may assume a conformation in which part of the channel located at the trans side is susceptible to some changes induced by the trans surface charge.

Determination of a cysteine protease inhibitor and its ethyl ester in mouse serum and muscle by liquid chromatography-mass spectrometry.

A liquid chromatographic-mass spectrometric method is described for the determination of a cysteine protease inhibitor (E64C) and its ethyl ester in mouse serum and muscle samples. The compounds in the sample, after deproteinization and solid-phase extraction, were separated by isocratic reversed-phase high-performance liquid chromatography and detected by on-line mass spectrometry. The use of an aqueous mobile phase containing methanol and 30 mM ammonium trichloroacetate provided abundant protonated molecular ions of the compounds in the atmospheric pressure chemical ionization interface of the detection system. The method permitted the quantitative determination of the inhibitors without internal standards in the biological matrices. The detection limits for the compounds, in the selected-ion monitoring mode, were 10-15 pmol on-column, at a signal-to-noise ratio of 5.

ATP as a biomass indicator for closed ecosystems.

Nucleotide measurements have been used as biomass indicators in microbial ecology. We report the use of this metric in materially closed, energetically open microbial ecosystems. Our results indicate that: (i) both ATP concentrations and pO2 show an increase from time of closure; (ii) ATP concentrations (0.2 1.2 ng/ml) are approximately 2 3 times higher than open ocean water; (iii) there is an apparent oscillation of ATP concentrations on the order of 50 days; and (iv) within experimental limitations the ratios of ATP concentrations to observed total cell counts is constant.