Studies of detrusor-sphincter synergia and dyssynergia during micturition in rats via fractional Brownian motion

Chang, Shyang; Mao, Shu-Ting; Hu, Shih-Jen; Lin, Wen-Ching; Cheng, Chen-Li

doi:10.1109/10.855934

Cited by 34 publications

(8 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Signals from the pons project directly to the S2-S4 sacral segments of the spinal cord and control the detrusor and urethral sphincter activity parasympathetically, resulting in normal storage and voiding [4]. Detrusor-sphincter dyssynergia has been reported in SCI patients [5]. …”

Section: Introductionmentioning

confidence: 99%

Simvastatin protects bladder and renal functions following spinal cord injury in rats

et al. 2010

View full text Add to dashboard Cite

BackgroundUrinary bladder and renal dysfunction are secondary events associated with spinal cord injury (SCI) in humans. These secondary events not only compromise quality of life but also delay overall recovery from SCI pathophysiology. Furthermore, in experimental models the effects of SCI therapy on bladder and renal functions are generally not evaluated. In this study, we tested whether simvastatin improves bladder and renal functions in a rat model of experimental SCI.MethodsSCI was induced by controlled contusion of T9-T10 in adult female rats. Simvastatin (5 mg/Kg body weight) was administered at two hours after SCI and repeated every 24 hours until the end point. Simvastatin-treated SCI animals (simvastatin group) were compared with vehicle-treated SCI animals (vehicle group) in terms of the Basso Beattie Bresnahan score, tissue morphology, cell death, and bladder/renal functions.ResultsThe urinary bladder of vehicle animals showed a 4.3-fold increase in size and a 9-fold increase in wet weight compared to sham animals. Following SCI, the urine to plasma osmolality ratio increased initially but decreased 1 week after SCI. Hematoxylin and eosin staining of bladder tissue showed transitional epithelial hyperplasia, degeneration of lamina propria, and enlargement of tunica adventia in addition to detrusor muscle hypertrophy. Rats treated with simvastatin for 14 days displayed remarkable recovery by showing decreased bladder size and maintenance of a normal urine/plasma osmolality ratio, in addition to improved locomotion. The muscularis layer of the bladder also regained its compact nature in simvastatin animals. Moreover, SCI-induced renal caspase-3 activity was significantly decreased in the simvastatin group indicating the ability of simvastatin to reduce the renal tubular apoptosis.ConclusionPost-injury administration of simvastatin ameliorates bladder and renal dysfunction associated with SCI in rats.

show abstract

Section: Introductionmentioning

confidence: 99%

Simvastatin protects bladder and renal functions following spinal cord injury in rats

et al. 2010

View full text Add to dashboard Cite

show abstract

“…Consequently, the sampled version of the surface EMG signals can be treated as discretetime fractional Brownian motion (DFBM). [4][5][6]25 It is clear from Eqs. (2) and (3) that the DFGN can be invoked to find the Hurst parameter H of the DFBM.…”

Section: Fractional Brownian Motion 27mentioning

confidence: 93%

“…22 However, recent studies have also illustrated that co-activations of muscles can be present for both normal and spinal cord injured Wistar rats during micturition. [3][4][5][6] The essential difference is that the former case of co-activation is synergic and the latter case dyssynergic. Here, the synergic co-activation is meant to be a state that involved muscles are not only active at the same time, but they also have the (1) same frequencies and (2) persistent signal intensities.…”

Section: Introductionmentioning

confidence: 98%

“…5,6 The importance of having the same frequencies with persistent intensities is equivalent to being synchronized with strength in physiological functions responding to external or internal stimuli. [3][4][5]17 The studies of muscles at forearm and their coactivation in human subjects have been concentrated on the patterns, abnormalities, and adaptions. 9,29,30 However, diagnostic and prognostic methods for ''dynamical disease'' 17 in forearm motion have not been proposed.…”

Section: Introductionmentioning

confidence: 99%

“…First, in order to detect the EMG rhythms, the time-frequency analysis using spectral distribution function (SDF) will be adopted in this paper. 6 Second, since these rhythms are usually embedded in correlated processes and it is well known that the muscular activities can exhibit power-law correlation, [3][4][5][6]19,36 fractal dimensions (FDs) will be invoked to extract the rhythm-dependent signal intensities of EMGs. [3][4][5][6][12][13][14]16,18,20,27,28,38 By combining both the FD and time-frequency analysis, we will investigate if the involved muscles will be under synergic co-activation during voluntary forearm pronation for normal subjects.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Synergic Co-activation in Forearm Pronation

et al. 2008

View full text Add to dashboard Cite

Co-activations of agonist and antagonist muscles are believed to be present in voluntary limb movement. Recent studies indicate that such co-activations are either synergic or dyssynergic. The aims of this paper are to (1) develop a novel method that can extract both the intensity and frequency information from the recordings of the surface electromyograms (EMGs) of involved muscles, and (2) investigate if the involved muscles will be under synergic co-activation during voluntary forearm pronation for normal subjects and dyssynergic co-activation for patients with radial nerve palsy. We examined 11 healthy subjects and 4 patients with right-arm radial nerve palsy in this study. For the group of healthy subjects, each one of them was asked to perform 30 trials of voluntary forearm pronation and then 30 trials of passive pronation as control experiments. As to the second group of patients, each one was asked to perform only 15 trials of voluntary pronation due to the limitation and durability of their arms. The recordings of the surface EMGs included the short and long heads of the biceps brachii, the brachialis, the lateral head of the triceps brachii, brachioradialis, and pronator teres. Experimental results of the healthy group indicated that the surface EMGs of all muscles had no statistically significant changes in fractal dimensions (FDs) and spectral frequencies of the control experiments during passive pronation. Yet, during the voluntary pronation experiments, the surface EMGs of all muscle groups were temporally synchronized in frequencies with persistent intensities. Hence, all involved muscle groups were in synergic co-activation. Statistical results of the group mean values of FDs during rest vs. forearm pronation also revealed significant difference with p < 0.01 for healthy subjects. As to the group of patients, their EMGs could still have bursting activities, but the synchronized significant frequencies might be lacking or the intensities as indicated from their FDs would not be persistent. To further compare the FDs among the three different protocols, a mixed-model ANOVA and multiple comparison tests were performed. Finally, in order to illustrate the advantages of this novel method, we have compared it with the detrended fluctuation analysis (DFA). It is believed that this proposed method will have the potential to be a biomarker for evaluating dynamical disease in neuromuscular disorders.

show abstract

Urinary bladder hyperreflexia: A rat animal model

Shaker

Mourad

Elbialy

et al. 2003

Neurourology and Urodynamics

View full text Add to dashboard Cite

In this work, we are presenting a rat animal model for bladder hyperreflexia after suprasacral spinal cord transection. Our aim was to standardize an animal model that can be useful in studying this condition. After standardizing the animal model in a pilot study, 26 female Sprague-Dawley rats were subjected to spinal cord transection at the level of T10 vertebra. Four animals were subjected to cystometrogram (CMG) 24 hr after spinalization and six rats 3 weeks post-spinalization. These CMGs were compared to that of six normal controls. The detailed description of the model presented in this manuscript, is the final result after several modifications. All the animals consistently developed hyperreflexia after an initial period of spinal shock phase. Expressed volume of urine continued to decrease until it reached a plateau after peaking at 1-week post-spinalization. The attrition rate reached 27.3% after several improvements in the animal model and was mostly from self-inflicted injuries. Post-operative complications included hypothermia, decubitus ulcers, hematuria, urinary tract infection in addition to the unexplained death of two animals. In conclusion, we believe that this animal model closely resembles the clinical condition of hyperreflexia and follows similar course. The relative low cost of this animal model and the easy maintenance makes it a valuable tool to study such a condition.

show abstract

Studies of detrusor-sphincter synergia and dyssynergia during micturition in rats via fractional Brownian motion

Cited by 34 publications

References 12 publications

Simvastatin protects bladder and renal functions following spinal cord injury in rats

Simvastatin protects bladder and renal functions following spinal cord injury in rats

Synergic Co-activation in Forearm Pronation

Urinary bladder hyperreflexia: A rat animal model

Contact Info

Product

Resources

About