Liver T1/T2 values with cardiac MRI during respiration.

BACKGROUND: Assessing the hepatic status of children with CHD is very important in the post-operative period. This study aimed to assess the usefulness of paediatric liver T1/T2 values and to evaluate the impact of respiration on liver T1/T2 values. METHODS: Liver T1/T2 values were evaluated in 69 individuals who underwent cardiac MRI. The mean age of the participants was 16.2 ± 9.8 years. Two types of imaging with different breathing methods were possible in 34 participants for liver T1 values and 10 participants for liver T2 values. RESULTS: The normal range was set at 620-830 msec for liver T1 and 25-40 ms for liver T2 based on the data obtained from 17 healthy individuals. The liver T1/T2 values were not significantly different between breath-hold and free-breath imaging (T1: 769.4 ± 102.8 ms versus 763.2 ± 93.9 ms; p = 0.148, T2: 34.9 ± 4.0 ms versus 33.6 ± 2.4 ms; p = 0.169). Higher liver T1 values were observed in patients who had undergone Fontan operation, tetralogy of Fallot operation, or those with chronic viral hepatitis. There was a trend toward correlation between liver T1 values and liver stiffness (R = 0.65, p = 0.0004); and the liver T1 values showed a positive correlation with the shear wave velocity (R = 0.62, p = 0.0006). CONCLUSIONS: Liver T1/T2 values were not affected by breathing patterns. Because liver T1 values tend to increase with right heart overload, evaluation of liver T1 values during routine cardiac MRI may enable early detection of future complications.

Incontinence and detrusor dysfunction associated with pelvic organ prolapse: clinical value of preoperative urodynamic evaluation.

INTRODUCTION AND HYPOTHESIS: We examined how preoperative urodynamic findings are related to the urinary problems following surgical repair of pelvic organ prolapse (POP). METHODS: The clinical records of 87 women who underwent surgery for POP were reviewed retrospectively. Preoperatively, cough stress test and urodynamic testing, including pressure-flow study, were performed with prolapse reduction. Postoperative evaluation included uroflowmetry, postvoid residuals, and symptom assessment using questionnaires. RESULTS: A cough stress test with simple filling was sufficient for diagnosis of occult stress urinary incontinence (SUI). The presence of detrusor overactivity was a good predictor of postoperative persistence of urgency and urge urinary incontinence. Postvoid residuals (PVR) largely increased immediately after surgery, but usually recovered within 1 month. Poor detrusor contractility was the best predictor of large PVR occurrence. CONCLUSIONS: Preoperative urodynamic evaluation of SUI and detrusor function was useful for predicting postoperative urinary conditions in POP patients. Its cost-effectiveness remains to be examined.

"Urgency tip": a portable patient-activated device for objective measurement of urinary urgency.

For clinical practice and research of overactive bladder syndrome, it is essential to evaluate urgency symptoms in daily life. We have developed a portable patient-activated device to record bladder sensations. This electronic device is pocket-size and light, with five grading buttons and another button for cancellation.

Amiloride-sensitive ion channels in urinary bladder epithelium involved in mechanosensory transduction by modulating stretch-evoked adenosine triphosphate release.

OBJECTIVES: To examine the possibility that mechanosensitive ion channels, including epithelial Na+ channels (ENaC), are implicated in mechanosensory transduction of the rat urinary bladder. METHODS: Cystometry with continuous infusion was performed to investigate the effect of intravesically perfused amiloride (a blocker of ENaC) on micturition reflex in urethane-anesthetized female rats. Bladder strips with or without epithelium suspended in organ bath were subjected to varying degrees of mechanical stretch (up to 50%). A luciferin-luciferase assay was used to quantify the change of stretch-evoked adenosine triphosphate (ATP) release by amiloride. The ENaC gene expression was assessed by reverse transcriptase-polymerase chain reaction. The expression and localization of ENaC proteins was examined using immunofluorescent staining. RESULTS: The intravesical perfusion of 1 mM amiloride significantly reduced the frequency of reflex voiding during bladder filling. This effect of amiloride was reversible by washing out the drug. The peak amplitude of micturition pressure was not affected by amiloride. The stretch-evoked ATP release, most of which (more than 90%) came from epithelial layer, was greatly diminished by 1 mM amiloride (from 443 to a 22% increase from basal level at 50% stretch of the original length). The alpha, beta, and gamma-ENaC subunit proteins and genes were expressed in the rat bladder epithelium. CONCLUSIONS: The amiloride-sensitive mechanosensitive channel, including ENaC, expressed in the rat bladder epithelium might be involved in the mechanosensory transduction mechanism by controlling stretch-evoked ATP release.

Prevalence and impact on generic quality of life of urinary incontinence in Japanese working women: assessment by ICI questionnaire and SF-36 Health Survey.

OBJECTIVES: To examine the prevalence of urinary incontinence (UI) and the relationship between UI and generic quality of life (QOL) in working women. METHODS: Of 7229 female hospital nurses in Japan, 3734 (51.7%) responded to a self-administered postal questionnaire that included the Rand Medical Outcomes Study 36-item Health Survey (SF-36) and the International Consultation on Incontinence questionnaire (ICIQ) for evaluating symptoms and health-related QOL. RESULTS: The overall prevalence of UI in Japanese working women aged 20 to 64 years (mean 35.2) was 16.7%. The main type of incontinence was stress UI (73%). Its prevalence increased with age and reached a plateau at age 45 to 49 years (34.7%). The ICIQ score also correlated significantly with age. Generic QOL, especially physical functioning, role-physical, social functioning, and role-emotional, was significantly impaired by UI. A comparison of subjects with and without UI revealed that the differences in the physical and mental component summary scores of the SF-36 were largest in the age groups of 25 to 29 and 55 to 59 years, respectively. The correlations of the ICIQ score with the physical and mental component scores were most significant in the age groups of 25 to 29 and 45 to 49 years, respectively. The impact of mixed UI on QOL showed a greater tendency than that of stress or urge UI. CONCLUSIONS: The prevalence of UI showed an age-related increase, with a peak at 45 to 49 years old. The impact of UI on physical health was great in individuals in their 20s, but its impact on mental health increased in the older age groups.

Overexpression of epithelial sodium channels in epithelium of human urinary bladder with outlet obstruction.

OBJECTIVES: To examine whether the epithelial sodium channel (ENaC) is expressed in the human urinary bladder and how its expression changes in association with outlet obstruction. Detrusor instability occurs in association with bladder outlet obstruction. The increase of afferent activity is one of the possible mechanisms for this detrusor instability. The ENaC expressed in mammals has been implicated in various mechanosensory functions. METHODS: Specimens of urinary bladder mucosa were obtained from 9 controls and 9 patients with bladder outlet obstruction verified by the International Prostate Symptom Score, prostate volume, and urodynamic tests. In 7 patients with outlet obstruction, involuntary detrusor contraction was demonstrated. The expression and localization of ENaC proteins was examined using immunofluorescent staining. The quantification of ENaC gene expression was assessed by real-time reverse transcriptase-polymerase chain reaction. RESULTS: The alpha-ENaC, beta-ENaC, and gamma-ENaC proteins were expressed in human urinary bladder epithelium with outlet obstruction, and the alpha-ENaC and gamma-ENaC proteins were virtually unstained in the control bladders. Alpha-ENaC, beta-ENaC, and gamma-ENaC mRNA were detected in 1, 6, and 4 of 9 control bladders, respectively. Each ENaC mRNA was clearly present in all obstructed bladders. The expression levels of each subunit in the obstructed bladders were significantly greater than those in controls. The quantified ENaC expression correlated significantly with the storage symptom score. CONCLUSIONS: The ENaC expressed in the bladder epithelium might be implicated in the mechanosensory transduction in the bladder afferent pathways, thereby inducing detrusor instability by outlet obstruction.

The methylentetrahydrofolate reductase C677T point mutation is a risk factor for vascular access thrombosis in hemodialysis patients.

BACKGROUND: Many reports indicate that a high homocysteine (Hcy) level is a potential risk factor for such thrombotic diseases as arteriosclerosis, myocardial infarction, and cerebral infarction in healthy individuals or hemodialysis (HD) patients. The methylentetrahydrofolate reductase (MTHFR) C677T polymorphism has been reported to be closely related to plasma Hcy level. METHODS: Using a cross-sectional design in this study, the relationship between arteriovenous fistula (AVF) obstruction and the MTHFR C677T point mutation was examined in 337 HD patients. RESULTS: Results of multivariate analysis showed no significant influence of age, HD therapy duration, sex, or the presence of diabetes mellitus, cerebral infarction, or myocardial infarction. Only the presence of the MTHFR C677T polymorphism yielded a significant difference. Percentages of patients who experienced AVF obstruction were as follows: CC (12.6%), CT (20.3%), and TT (31.8%). The number of those who experienced obstruction was significantly larger with the TT than CC (P < 0.01). Moreover, total obstruction episode ratios were as follows: CC, 1 in 107.21 episodes/patient-month; CT, 1 in 74.08 episodes/patient-month; and TT, 1 in 50.33 episodes/patient-month. Episode percentages tended to be greater when the degree of mutation was greater, and a significant difference was observed between the CC and TT alleles (P < 0.01). CONCLUSION: Although AVF obstruction is affected by numerous factors, there was a strong relationship between MTHFR C677T mutation and AVF obstruction. These findings suggest that the MTHFR C677T point mutation could serve as an important indicator in identifying susceptibility to AVF obstruction.