Prenatal environmental conditions affect the development of the fetus. In the present study, we investigated the effects of exposure to music and noise during pregnancy on neurogenesis and thickness in the motor and somatosensory cortex of rat pups.
The pregnant rats in the music-applied group were exposed to 65 dB of comfortable music for 1 hour, once per day, from the 15th day of pregnancy until delivery. The pregnant rats in the noise-applied group were exposed to 95 dB of sound from a supersonic sound machine for 1 hour, once per day, from the 15th day of pregnancy until delivery. After birth, the offspring were left undisturbed together with their mother. The rat pups were sacrificed at 21 days after birth.
Exposure to music during pregnancy increased neurogenesis in the motor and somatosensory cortex of rat pups. In contrast, rat pups exposed to noise during pregnancy showed decreased neurogenesis and thickness in the motor and somatosensory cortex.
Our study suggests that music and noise during the developmental period are important factors influencing brain development and urogenital disorders.
Music; Noise; Neurogenesis; Motor cortex; Somatosensory cortex
Stress has a deteriorating effect on hippocampal function. It also contributes to symptom exacerbation in many disease states, including overactive bladder and interstitial cystitis/bladder pain syndrome. We investigated the effects of various types of stresses (restraint, noise, and cold) on short-term memory and apoptosis in relation with corticotropin-releasing factor (CRF) expression.
Rats in the restraint stress group were restrained in a transparent Plexiglas cylinder for 60 minutes twice daily. Rats in the noise stress group were exposed to the 120 dB supersonic machine sound for 60 minutes twice daily. Rats in the cold stress group were placed in a cold chamber at 4℃ for 60 minutes twice daily. Each stress was applied for 10 days. A step-down avoidance test for short-term memory, immunohistochemistry for caspase-3 expression, and western blot analysis for Bax and Bcl-2 expressions were conducted.
Latency time was decreased and CRF expression in the hippocampal dentate gyrus and hypothalamic paraventricular nucleus were increased in all of the stress groups. The number of caspase-3-positive cells in the hippocampal dentate gyrus was increased and the expressions of Bax and Bcl2 in the hippocampus were decreased in all of the stress groups.
All of the stress groups experienced short-term memory impairment induced by apoptosis in the hippocampus. The present results suggest the possibility that these stresses affecting the impairment of short-term memory may also induce functional lower urinary tract disorders.
Restrain stress; Noise stress; Cold stress; Short-term memory; Apoptosis
To find the association of trial without catheter (TWOC) outcome for first spontaneous acute urinary retention (AUR) in benign prostatic obstruction with age, prior lower urinary tract symptoms (LUTS), retention volume at catheterization (RV), and size of prostate.
Our prospective observational analytical (interventional) study enrolled 77 cases of spontaneous AUR over 24 months. After clinical evaluation, digital rectal examination, and transabdominal ultrasonography, all patients were catheterized per urethra and their RV was recorded. TWOC was administered after 2 or 3 doses of 0.4 mg tamsulosin-oral absorption control system and after 48-72 hours had passed. A successful endpoint was defined as a maximum flow-rate, >5 mL/sec; voided volume, >100 mL; postvoid residue, <200 mL; and voiding within 6 hours of catheter removal. Data obtained from 58 patients were analyzed after excluding the cases lost to follow-up and secondary exclusion. Age, RV, duration of LUTS, and prostate volume on examination and ultrasonography (PUSG) were recorded and statistically analyzed. Prostate-specific antigen levels were obtained on follow-up and cases of cancer, as seen on transrectal ultrasound-guided biopsy, were secondarily excluded.
The patients had a mean age of 65.89±8.67 years. Prior LUTS was seen in 35 patients (2.07±2.91 months). The mean PUSG and RV were 46.81±20.58 mL and 854.8±36.26 mL, respectively. Thirty patients underwent a successful TWOC; a mean age of 63.13±8.58 years (mean±standard deviation; unpaired t-test; P=0.0053) and a PUSG of ≤45 mL (Pearson chi-square test; P=0.0427) were significantly associated with a successful outcome.
There is a significant association between TWOC outcome, age (P=0.0053), and PUSG (P=0.0427).
Urinary retention; Tamsulosin; Urination disorders
Symptoms of urinary bladder detrusor dysfunction have been rarely reported in Lyme disease. The aim was to carry out the first systematic study to compare the prevalence of such symptoms in a group of Lyme disease patients and a group of matched controls.
A questionnaire relating to detrusor function was administered to 17 serologically positive Lyme disease patients and to 18 control subjects.
The two groups were matched in respect of age, sex, body mass, and mean arterial blood pressure. None of the 35 subjects was taking medication which might affect urinary function and none had undergone a previous operative procedure on the lower urinary tract. Six of the Lyme patients (35%) and none of the controls (0%) had symptoms of detrusor dysfunction (P<0.01).
This first systematic controlled study confirms that Lyme disease is associated with urinary bladder detrusor dysfunction. Further evaluation of detrusor function is warranted in this disease.
Bladder function; Lyme disease; Urinary bladder
An overactive bladder (OAB) may be defined as urgency that is a sudden, compelling, difficult to defer desire to pass urine that is usually accompanied by frequency and nocturia and possibly by incontinence. Obesity and old age are two factors in various causes of OAB. Several epidemiologic studies have identified positive associations among obesity, old age, urinary incontinence, and OAB. However, although exercise has been known to improve obesity and reduce incontinent urine loss, little research has been done in elderly women. Therefore, we investigated the effects of exercise on obesity-related metabolic factors, blood lipid factors, and OAB symptoms in elderly Korean women.
Twenty-one women aged between 69 and 72 years were recruited from the Seoul senior towers in Korea. All subjects worked out on a motorized treadmill and stationary cycle for 40 minutes, respectively, and performed resistance exercise for 30 minutes once a day for 52 weeks. Body composition, blood pressure, blood lipids, OAB symptom score, and King's health questionnaire were investigated and analyzed.
Before performing physical exercise, all subjects showed increased OAB symptoms in association with enhanced body mass index (BMI), percentage fat, and blood lipid profiles. However, physical exercise for 52 weeks suppressed BMI, percentage fat, and blood lipid profiles and thus improved OAB symptoms.
We suggest that long-term physical exercise can be a valuable tool for remarkable improvement of OAB.
Overactive urinary bladder; Obesity; Exercise; Overactive bladder symptom score; King's health questionnaire
In pediatric patients with enuresis, the protocol for salvage therapy in patients in whom first-line therapy was not successful has not yet been established. Interferential electrical stimulation (IF-ES) therapy is advantageous because it is noninvasive and shows high compliance. We aimed to investigate the efficacy and safety of IF-ES therapy on pediatric enuresis in a pilot study.
We investigated 10 patients who underwent IF-ES therapy between August 2012 and March 2013 at our clinic. Patients with a history of previous treatment with desmopressin and anticholinergic agents for at least 3 months and those in whom alarm treatment previously failed or was refused by parents were eligible. Electrical current was given starting at approximately 20 mA and was increased until the patient complained of discomfort. Treatment was performed once a week, 20 minutes per treatment, 6 times per cycle. After each cycle, an interview was performed and voiding diaries were filled. The physician in charge evaluated improvement according to the International Children's Continence Society criteria.
A final analysis was performed in 10 patients (5 male and 5 female patients) in whom therapy for nocturnal enuresis had failed. Eight patients had nonmonosymptomatic enuresis and 2 had monosymptomatic enuresis. The mean age of the patients was 8.5±2.4 years, and the mean number of treatments was 10.6±3.6 times. A full response was observed in 1 patient (10%); a good response, in 1 patient (10%); a partial response, in 7 patients (70%); and no response, in 1 patient (10%).
Our study demonstrated that IF-ES therapy can be a promising treatment for the future, is safe, and can benefit from appropriate clinical trials in carefully selected groups. IF-ES therapy is expected to be a safe and effective treatment modality for children with enuresis.
Electric stimulation; Enuresis; Salvage therapy
We compared the effectiveness of the retropubic tension-free vaginal tape (TVT) and the transobturator inside-out tape (TVT-O) in treating symptoms of overactive bladder (OAB) in women with stress urinary incontinence (SUI).
Women with urodynamic SUI and OAB (mean urgency episodes ≥1 and frequency ≥8/24 hours on a 3-day voiding diary) were assigned to the TVT or TVT-O group. Preoperative measures were based on a urodynamic study, 3-day voiding diary, the Bristol Female Lower Urinary Tract Symptoms questionnaire (BFLUTSSF), and the urgency perception scale (UPS). At 12 postoperative months, the 3-day voiding diary, symptoms questionnaire, patient satisfaction, and standing stress test were assessed. The primary endpoint was change in the number of urgency episodes/24 hours from baseline to 12 months.
In this group of 132 women, 42 received TVT and 90 received TVT-O. The mean urgency episodes/24 hours decreased from 6.3±5.5 to 1.6±3.2 in the TVT group and from 5.1±4.4 to 1.8±3.0 in the TVT-O group. The mean percent change was significantly greater after TVT than after TVT-O (73% vs. 60%, P=0.049). All subscales of BFLUTSSF and UPS were significantly improved using either method, with significantly greater improvement seen in the quality of life (QoL) domain after TVT (P=0.002). There were no significant differences in the cure and satisfaction rates between the two groups.
Intervention with the TVT or the TVT-O significantly improved symptoms of OAB in women with SUI and OAB. Urgency and QoL significantly improved after TVT compared with that after TVT-O.
Overactive urinary bladder; Stress urinary incontinence
From the first pacemaker implant in 1958, numerous engineering and medical activities for implantable medical device development have faced challenges in materials, battery power, functionality, electrical power consumption, size shrinkage, system delivery, and wireless communication. With explosive advances in scientific and engineering technology, many implantable medical devices such as the pacemaker, cochlear implant, and real-time blood pressure sensors have been developed and improved. This trend of progress in medical devices will continue because of the coming super-aged society, which will result in more consumers for the devices. The inner body is a special space filled with electrical, chemical, mechanical, and marine-salted reactions. Therefore, electrical connectivity and communication, corrosion, robustness, and hermeticity are key factors to be considered during the development stage. The main participants in the development stage are the user, the medical staff, and the engineer or technician. Thus, there are three different viewpoints in the development of implantable devices. In this review paper, considerations in the development of implantable medical devices will be presented from the viewpoint of an engineering mind.
Biomedical engineering; Medical electronics; Micro-electro-mechanical systems; Biocompatible materials
Rat cystometry is increasingly being used in research on overactive bladder and is a research tool for investigating bladder functions during the storage and voiding phases. Measurement of the pressure in the bladder is an essential part of cystometry, although that pressure is the sum of both detrusor and intra-abdominal pressures. In anesthetic cystometry, measurement of the intra-abdominal pressure is not necessary, because the values of this variable are negligible. In awake cystometry, however, it is mandatory to separate the changes in intra-abdominal pressure from those in intravesical pressure, because consciousness causes much variability in intra-abdominal pressure. This review describes why we use the term "detrusor overactivity" in animal research with intra-abdominal pressure and presents evidence for the role of intra-abdominal pressure in the cystometry of normal rats and in animal models of overactive bladder directed at understanding the pathogenesis of the overactive bladder condition. The methodology is also briefly reviewed.
Urinary bladder; Overactive; Physiology; Rat; Urodynamics
Persistent and disabling pain is the hallmark of chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS). However, disease severity (as measured by objective indexes such as those that use radiography or serology) is only marginally related to patients' reports of pain severity, and pain-related presentation can differ widely among individuals with CP/CPPS. Increasing evidence in support of the biopsychosocial model of pain suggests that cognitive and emotional processes are crucial contributors to inter-individual differences in the perception and impact of pain. This review describes the growing body of literature relating depression and catastrophizing to the experience of pain and pain-related sequelae in CP/CPPS. Depression and catastrophizing are consistently associated with the reported severity of pain, sensitivity to pain, physical disability, poor treatment outcomes, and inflammatory disease activity and potentially with early mortality. A variety of pathways, from cognitive to behavioral to neurophysiological, seem to mediate these deleterious effects. Collectively, depression and catastrophizing are critically important variables in understanding the experience of pain in patients with CP/CPPS. Pain, depression, and catastrophizing might all be uniquely important therapeutic targets in the multimodal management of a range of such conditions.
Pain; Catastrophization; Depression; Prostatitis
Thanks to advancements in surgical techniques and instruments, many surgical modalities have been developed to replace transurethral resection of the prostate (TURP). However, TURP remains the gold standard for the surgical treatment of benign prostatic hyperplasia (BPH). We conducted a meta-analysis on the efficacy and safety of minimally invasive surgical therapies for BPH compared with TURP.
This meta-analysis used a Medline search assessing the period from 1997 to 2011. A total of 784 randomized controlled trials were identified in an electronic search. Among the 784 articles, 36 randomized controlled trials that provided the highest level of evidence (level 1b) were included in the meta-analysis. We also conducted a quality analysis of selected articles.
Only 2 articles (5.56%) were assessed as having a low risk of bias by use of the Cochrane collaboration risk of bias tool. On the other hand, by use of the Jadad scale, there were 26 high-quality articles (72.22%). Furthermore, 28 articles (77.78%) were assessed as high-quality articles by use of the van Tulder scale. Holmium laser enucleation of the prostate (HoLEP) showed the highest reduction of the International Prostate Symptom Score compared with TURP (P<0.0001). Bipolar TURP, bipolar transurethral vaporization of the prostate, HoLEP, and open prostatectomy showed superior outcome in postvoid residual urine volume and maximum flow rate. The intraoperative complications of the minimally invasive surgeries had no statistically significant inferior outcomes compared with TURP. Also, there were no statistically significant differences in any of the modalities compared with TURP.
The selection of an appropriate surgical modality for BPH should be assessed by fully understanding each patient's clinical conditions.
Prostatic hyperplasia; Holmium; Lasers; Potassium titanylphosphate; Transurethral resection of prostate; Meta-analysis
Bladder wall thickness has been reported to be associated with overactive bladder (OAB) in women. Diabetic women have an increased risk for OAB syndrome and may have an increased risk for bladder wall thickness.
A total of 235 female patients aged 40 to 75 years were categorized into four groups. The first group consisted of women free of urgency or urge urinary incontinence. The second group included nondiabetic women with idiopathic OAB. The third group consisted of women with diabetes and clinical OAB, and women with diabetes but without OAB constituted the fourth group. Bladder wall thickness at the anterior wall was measured by ultrasound by the suprapubic approach with bladder filling over 250 mL.
The diabetic (third group) and nondiabetic (second group) women with OAB had significantly greater bladder wall thickness at the anterior bladder wall than did the controls. However, the difference was not significant between the diabetic (third group) and the nondiabetic (second group) women with OAB. Women with diabetes but without OAB (fourth group) had greater bladder wall thickness than did the controls but this difference was not significant. Additionally, the difference in bladder wall thickness between diabetic women with (third group) and without (fourth group) OAB was not significant.
This is the first study to show that bladder wall thickness is increased in diabetic women with and without OAB. Additionally, nondiabetic women with OAB had increased bladder wall thickness. Further studies may provide additional information for diabetic and nondiabetic women with OAB, in whom the etiopathogenesis of the disease may be similar.
Overactive urinary bladder; Urinary bladder; Diabetes mellitus
To investigate the efficacy of total prostate-specific antigen (tPSA) and free prostate-specific antigen (fPSA) for the estimation of prostate volume (PV) in pathologically-proven benign prostatic hyperplasia (BPH) patients.
From January 2010 to March 2013, 165 Korean men with a PSA less than 10 ng/mL who were diagnosed without prostate cancer by prostate biopsy were enrolled. Patients were classified into three age groups: ≤60, 61-70, and >70 years old. The results were organized to estimate and compare the ability of serum tPSA and fPSA to assess the PV.
Enrolled patients had a median age of 63.5 years (44 to 80), a median tPSA of 5.72 ng/mL, a median fPSA of 0.98 ng/mL and a median PV of 53.68 mL, respectively. Among the associations between tPSA, fPSA, age, and PV, the highest correlation was verified between fPSA and PV (r=0.377, P<0.0001); the correlation coefficient between tPSA and PV was much lower (r=0.262, P<0.001). All stratified age cohorts showed the same findings. The ROC curves (for PV greater than 30, 40, and 50 mL) showed that fPSA (area under the curve [AUC]=0.781, 0.718, and 0.700) outperformed tPSA (AUC=0.657, 0.583, and 0.67) in its ability to predict clinically significant PV enlargement.
Both tPSA and fPSA significantly correlated with PV in Korean men, while the correlation efficiency between fPSA and PV was more powerful. fPSA may be a useful tool in making therapeutic decisions and follow-up management in BPH patients.
Prostate-specific antigen; Prostatic hyperplasia; Organ volume
Patients with bladder pain syndrome/interstitial cystitis (BPS/IC) can have pain as a main symptom and overactive bladder (OAB) symptoms that are directly or indirectly related to a major mechanism that causes pain. The primary purpose of this study is firstly to identify the prevalence rate of OAB symptoms in patients with BPS/IC, secondly to identify changes in OAB symptoms after low-dose triple therapy, and thirdly to build a theoretical foundation to improve quality of life for patients.
Patients who met the inclusion criteria of BPS/IC through basic tests including the O'Leary-Sant symptom index, overactive bladder symptom score (OABSS), and visual analog scale (VAS) were identified. Treatment-based changes in OAB symptoms were identified using the IC Symptom Index and IC Problem Index (ICSI/ICPI), OABSS, and VAS before, and 4 and 12 weeks after low-dose triple therapy.
The patients consisted of 3 men and 20 women, and their mean age was 61.9 years (41.0-83.2 years). Comparing values before treatment, and 4 and 12 weeks after treatment (baseline vs. 4 weeks to baseline vs. 12 weeks), the rates of improvement were as follows: ICSI, 44.2% to 63.7%; ICPI, 46.9% to 59.4%; OABSS, 34.3% to 58.2%; and VAS, 53.6% to 75.0%, which showed statistically significant differences (P<0.05). However, comparing values at 4 and 12 weeks after treatment (4 weeks vs. 12 weeks), the ICSI and VAS showed a statistically significant decrease (P<0.05). The ICPI and OABSS showed slight improvement, but no statistically significant differences (P>0.05).
Low-dose triple therapy in BPS/IC results in a clear decrease in OAB symptoms in the first 4 weeks after treatment, and additional treatment for 8 weeks had a partial effect with varied statistical significances depending on the questionnaires.
Overactive bladder; Bladder pain syndrome; Interstitial cystitis
The aim of this study was to investigate the preoperative factors related to early quality of life (QoL) in patients with benign prostatic hyperplasia after holmium laser enucleation of the prostate (HoLEP) during the surgeon's learning curve.
The medical records of 82 patients with a follow-up period of at least 3 months who were treated with HoLEP during the time of a surgeon's learning curve were analyzed retrospectively. We divided the patients into two groups on the basis of the QoL component of the International Prostate Symptom Score (IPSS) 3 months after HoLEP: the high QoL group (IPSS/QoL≤3) and the low QoL group (IPSS/QoL≥4). Preoperative factors in each group were compared, including prostate volume, prostate-specific antigen, history of acute urinary retention (AUR), urgency incontinence, IPSS, and urodynamic parameters. Detrusor underactivity was defined as a bladder contractility index less than 100 on urodynamic study.
A total of 61 patients (74.3%) had a high QoL, whereas 21 (25.7%) had a low QoL. A history of AUR, detrusor pressure on maximal flow (PdetQmax), bladder outlet obstruction grade, bladder contractility index, and detrusor underactivity were associated with postoperative QoL in the univariate analysis. In the multivariate analysis, a history of AUR and PdetQmax were independent factors affecting postoperative QoL.
A history of AUR and bladder contractility affect early QoL, and preoperative urodynamic study plays an important role in the proper selection of patients during the HoLEP learning curve.
Prostatic hyperplasia; Holmium; Lasers; Quality of life
We report a case of ureteral migration of a surgical clip after partial nephrectomy in which the clip was misdiagnosed as a ureteral stone. A 37-year-old woman had undergone laparoscopic partial nephrectomy of right renal cell carcinoma at another hospital 2 years previously. Postoperatively, she had gradually acquired lower urinary tract symptoms. Then, she complained of sudden right flank pain for a week. A plain X-ray and enhanced abdominopelvic computed tomography scan were performed. A 0.5 cm×1.0 cm right upper ureteral opacity with borderline hydronephrosis was seen but could not be found on the X-ray. Ureteroscopy revealed a medium-sized Hem-o-Lok clip on the right upper ureter that was removed with a stone basket. We concluded that a Hem-o-Lok clip used for collecting system sealing had migrated to the ureter and had been misdiagnosed as a ureteral stone on a computed tomography scan.
Nephrectomy; Surgical instruments; Ureteral calculi
A 49-year-old man was referred to our department with profuse serous fluid discharge from a Penrose drain after undergoing internal fixation with metal screws for multiple pelvic bone fractures. A definite ureteral penetration was identified that was orientated from the lateral to the medial aspect of the right distal ureter. The patient was surgically treated with excision of the 2-cm injured ureteral segment, end-to-end ureteroureterostomy, and double J ureteral stent placement. To our knowledge, a penetrating ureteral injury caused by bone drilling has not been reported previously in the published literature. This case shows that surgeons who do pelvic surgery, including orthopedic surgeons, should be familiar with the anatomical relationship of the ureter and its potential injuries.
Ureter; Drilling; Injury
This study was to investigate whether a systematized bladder training (BT) program is effective for patients with idiopathic overactive bladder (OAB).
A prospective study was conducted on 105 patients with OAB from March 2009 to November 2011. We developed a 30 minutes BT program, which consisted of first, refraining from going to the bathroom after feeling an urge to void, second, in order to stop thinking about voiding, ceasing action and thought temporarily, and third, performing pelvic floor exercises 5 to 6 times. Before and after BT, the patients filled out voiding diaries as well as the following questionnaires; International Consultation on Incontinence Questionnaire for overactive bladder (ICIQ-OAB), International Prostate Symptom Score (IPSS), overactive bladder questionnaire (OAB-q), the short form 36-item health survey (SF-36) questionnaire, the work productivity and activity impairment questionnaire, and a patients' perception of treatment benefit (PPTB).
A final analysis was performed from on 85 patients (38 male, 47 female) with idiopathic OAB. After the first BT, the results of the ICIQ-OAB showed improvement in frequency, nocturia, and urgency (P<0.05), and all domains of IPSS questionnaires showed significant improvement (P<0.05). Among the SF-36 domains, the role-physical domain showed significant improvement after the first BT, and the general health domain showed significant improvement after the second. The voiding diaries showed statistically significant changes in maximal voided volume after the first BT, and nocturia index and nocturnal polyuria index after the second BT. According to the PPTB questionnaire, the perceived usefulness of BT increased after each session, and almost all of the patients replied that BT improved their symptoms.
Our results demonstrated that BT was effective in improving many OAB related symptoms and quality of life in patients with idiopathic OAB. More clinical application of BT could be implemented in the future.
Behavior modification; Overactive urinary bladder; Quality of life
Despite reports of persistent stress urinary incontinence (SUI) in patients after the midurethral sling (MUS) procedure, there is no widely accepted definition or cause of the condition. In many cases, the mesh implanted in the previous MUS procedure has been found to have migrated proximally. The aim of this study was to evaluate the efficacy of the modified distal urethral polypropylene sling, or canal transobturator tape (TOT), procedure for persistent SUI after a conventional MUS procedure on the assumption that persistent SUI after MUS is due to the location of the sling.
From January 2008 to April 2012, 31 female patients who underwent the canal TOT procedure presented with incontinence or lower urinary tract symptoms (LUTS) were included in this study. We identified patients who had been operated on by use of the conventional MUS procedure at other medical facilities, whose Valsalva leak pressure point was less than 120 cm-H2O by urodynamic study, and who were also diagnosed with persistent SUI. If vaginal or urethral mesh exposure was concomitant with persistent SUI, the mesh was removed completely or in part. Surgical procedures for canal TOT were identical to the original TOT procedures, except in the number and location of the vaginal incisions. Incontinence Impact Questionnaire-Short Form (IIQ-7) and Urogenital Distress Inventory-Short Form (UDI-6) scores were assessed preoperatively and at 3 months postoperatively.
There were no intraoperative or postoperative complications. Twenty-eight patients (90.3%) showed improvement in incontinence or other LUTS. Postoperative scores of the IIQ-7 (0.65±0.48) and UDI-6 (3.48±2.28) were significantly improved compared with preoperative scores (1.26±0.58 and 7.52±4.30, respectively; P<0.05).
Improper sling location is one of the major causes of persistent SUI after the conventional MUS procedure. Our results demonstrate that canal TOT may be an alternative method in the treatment of persistent SUI after the conventional MUS procedure.
Stress urinary incontinence; Suburethral slings; Recurrence
We present the construction of the lab-on-a-chip (LOC) system, a state-of-the-art technology that uses polymer materials (i.e., poly[dimethylsiloxane]) for the miniaturization of conventional laboratory apparatuses, and show the potential use of these microfluidic devices in clinical applications. In particular, we introduce the independent unit components of the LOC system and demonstrate how each component can be functionally integrated into one monolithic system for the realization of a LOC system. In specific, we demonstrate microscale polymerase chain reaction with the use of a single heater, a microscale sample injection device with a disposable plastic syringe and a strategy for device assembly under environmentally mild conditions assisted by surface modification techniques. In this way, we endeavor to construct a totally integrated, disposable microfluidic system operated by a single mode, the pressure, which can be applied on-site with enhanced device portability and disposability and with simple and rapid operation for medical and clinical diagnoses, potentially extending its application to urodynamic studies in molecular level.
Lab-on-a-chip devices; Polymers; Disposable equipment; Micro-electrical-mechanical systems; Miniaturization; Diagnosis