Probing penile hemodynamics by using photoplethysmography as objective indicators for male erection quality and sexual function.

Erectile dysfunction (ED) is mostly due to the lack of blood flow into the penis. In the past 20 years, near-infrared spectroscopy (NIRS) was used in measuring the concentrations and temporal dynamics of different hemoglobin types. However, the dynamics of the light absorption (photoplethysmography; PPG) have not been applied to survey penile hemodynamics and erection quality. This paper compared the use of photoplethysmography (PPG) to study vascular ED with standard penile Doppler ultrasonography. Men diagnosed with vascular ED for at least 6 months and nominated for penile ultrasonography were included. PPG signals were collected during the ultrasound examination. All beat-to-beat PPG waveforms were aligned with the peak and averaged to one representative template waveform for feature analysis, including amplitude differences (APD) index, reflection time index (RTI), augmentation index (AI), and perfusion index (PI). An inverse correlation was found between end-erection amplitude and both erection hardness score (EHS) and resistive index (RI). APD index and EHS as well as the international index of erectile function-5 (IIEF) and RI were positively correlated. RTI and AI were inversely correlated to IIEF and RI. PI was positively correlated to RI. PPG may therefore be useful as a noninvasive, convenient, technique for sexual function evaluation.

Validating METCAM/MUC18 as a Novel Biomarker to Predict the Malignant Potential of Prostate Cancer at an Early Stage by Using a Modified Gold Nanoparticles-Based Lateral Flow Immunoassay.

(1) Background: To further validate METCAM/MUC18 as a diagnostic biomarker for prostate cancer, a modified Lateral Flow Immune Assay (LFIA) with increased sensitivity and specificity was designed by taking advantage of the extremely high affinity between biotin and streptavidin and used. (2) Methods: The combination of a commercial biotinylated rabbit antibody (EPP11278), or the home-made biotinylated chicken antibody, and the nano-gold conjugated home-made chicken antibody or a commercial rabbit antibody (EPP11278), had the higher sensitivity and specificity in this modified LFIA to establish calibration curves from the two recombinant METCAM/MUC18 proteins and were used for determining METCAM/MUC18 concentrations in serum specimens from normal individuals, benign prostatic hyperplasia (BPH) patients, prostatic intraepithelial neoplasia (PIN) patients, prostate cancer patients with various Gleason scores, and treated patients. (3) Results: Data obtained by this modified LFIA were statistically better than traditional LFIA and prostate-specific antigen (PSA) test. Interestingly, serum METCAM/MUC18 concentrations were higher in pre-malignant PIN patients than prostate cancer patients and both were higher than normal individuals, BPH patients, and treated patients. Serum METCAM/MUC18 concentrations were directly proportional to most serum PSA. (4) Conclusions: Elevated serum METCAM/MUC18 concentrations may be used for predicting the malignant potential of prostate cancer at an early premalignant (PIN) stage, which is not achievable by the current PSA test.

METCAM/MUC18 is a new early diagnostic biomarker for the malignant potential of prostate cancer: Validation with Western blot method, enzyme-linked immunosorbent assay and lateral flow immunoassay.

BACKGROUND: METCAM/MUC18 expression was increased with the malignant progression of prostate cancer and also a bona fide metastatic gene, capable of initiating and driving the metastasis of a non-metastatic human prostate cancer cell line to multiple organs. OBJECTIVE: We explored if METCAM/MUC18 was detectable in human serum and a novel biomarker to predict malignant propensity of prostate cancer. MATERIALS AND METHODS: Two antibodies were identified by Western blot analysis having the highest sensitivity and specificity to establish calibration curves from the recombinant METCAM/MUC18 proteins. They were used in ELISA and LFIA to determine the METCAM/MUC18 concentrations in serum samples from 8 normal individuals, 4 BPH patients, 1 with PIN, 6 with high-grade prostate cancer, and 2 treated cancer patients. RESULTS: Serum METCAM/MUC18 concentrations were statistically significantly higher in the patients with PIN and prostate cancer than those with BPH, the treated patients and normal individuals. The LFIA results were statistically better than ELISA and Western blot methods. Serum METCAM/MUC18 concentrations were in direct proportional to most of serum PSA concentrations.

The potential of at-home prediction of the formation of urolithiasis by simple multi-frequency electrical conductivity of the urine and the comparison of its performance with urine ion-related indices, color and specific gravity.

It is important to control daily diet, water intake and life style as well as monitor the quality of urine for urolithiasis prevention. For decades, many ion-related indices have been developed for predicting the formation of urinary stones or urolithiasis, such as EQUILs, relative supersaturation (RSS), Tiselius indices (TI), Robertson risk factor algorithms (RRFA) and more recently, the Bonn risk index. However, they mostly demand robust laboratory analysis, are work-intensive, and even require complex computational programs to get the concentration patterns of several urine analytes. A simple and fast platform for measuring multi-frequency electrical conductivity (MFEC) of morning spot urine (random urine) to predict the onset of urolithiasis was implemented in this study. The performance thereof was compared to ion-related indices, urine color and specific gravity. The concentrations of relevant ions, color, specific gravity (SG) and MFEC (MFEC tested at 1, 10, 100, 5001 KHz and 1 MHz) of 80 random urine samples were examined after collection. Then, the urine samples were stored at 4 °C for 24 h to determine whether sedimentation would occur or not. Ion-activity product index of calcium oxalate (AP(CaOx) EQ2) was calculated. The correlation between AP(CaOx) EQ2, urine color, SG and MFEC were analyzed. AP(CaOx) EQ2, urine color and MFEC (at 5 frequencies) all demonstrated good prediction (p = 0.01, 0.01, 0.01, respectively) for stone formation. The positive correlation between AP(CaOx) EQ2 and MFEC is also significant (p = 0.01). MFEC provides a good metric for predicting the onset of urolithiasis, which is comparable to conventional ion-related indices and urine color. This technology can be implemented with much ease for objectively monitoring the quality of urine at points-of-care or at home.

The Biochemical and Pathological Correlates of Successful Semen Cryopreservation From Patients With Testicular Cancer: A Single Tertiary Center Experience.

OBJECTIVE: To determine the predictors for success with regard to semen cryopreservation and good semen quality of patients with testicular cancer. MATERIALS AND METHODS: A total of 50 men (aged 16-36 years) with testicular cancer, referred for semen cryopreservation prior to gonadotoxic treatment, were included. Age, alpha fetal protein (α-FP), beta human chorionic gonadotropin, lactate dehydrogenase, clinical staging, tumor volume, and pathological reports were evaluated as correlates of successful semen cryopreservation and good semen quality. RESULTS: The overall success rate was 52%. α-FP (4113.1 ng/mL vs 81.2 ng/mL) and tumor volume (77.7 mL vs 25.5 mL) were significantly higher in the failure group as compared to the success group. The seminoma to nonseminomatous germ cell tumor ratio was lower in the failure group as compared to the success group (9/17 vs 3/21). There was nearly a significant difference (P = .066). The optimal cutoff value for α-FP > 1000 ng/mL showed the highest Youden index (0.689) and resulted in a sensitivity of 0.625 and specificity of 1.0 for predicting poor outcome. In terms of multivariate analysis, the α-FP (P = .013), tumor volume (P = .047), and α-FP > 1000 ng/mL (P = .010) were significantly associated with poor semen quality and failure to preserve semen. Sperm quality was found to be higher in the seminoma versus the nonseminomatous germ cell tumor patients in: sperm concentration (21.5 million/mL vs 11.8 million/mL, P < .027). Furthermore, tumor volume is correlated to α-FP (P = .018) and is weakly correlated to lactate dehydrogenase (P = .067) CONCLUSION: Elevated α-FP and tumor volume are independently poor factors for semen quality and semen cryopreservation. In clinical use, α-FP is a noninvasive tool to predict the success of semen cryopreservation and patients with α-FP > 1000 ng/mL should be informed of the higher risk of poor semen quality and semen cryopreservation concerns.

Temporal trend of newly diagnosed incidence, medical utilization, and costs for pediatric urolithiasis, 1998-2007: a nationwide population-based study in Taiwan.

OBJECTIVE: To investigate the trends of newly diagnosed incidence, medical utilization, and medical costs for pediatric urolithiasis in Taiwan. MATERIALS AND METHODS: The present study uses the National Health Insurance Research Database, which contains the data of all medical benefit claims from the individuals enrolled in the national and single-payer insurance program in Taiwan. The National Health Insurance covered 22,717,053 enrollees, nearly 99% of Taiwan's population. Our analysis includes all subjects aged <18 years with a primary diagnosis of urolithiasis. We analyzed the temporal trend for annual newly diagnosed incidence, medical care visits, and medical costs for pediatric urolithiasis from 1998 to 2007. RESULTS: A total of 1474 patients aged <18 years with newly diagnosed urolithiasis were identified, including 719 (48.8%) boys and 755 (51.2%) girls. The overall newly diagnosed rate of urolithiasis in pediatric population was 0.038% in 2007. The peak age stratum of urolithiasis occurrence in 2007 was 15-18 years. The trend of annual newly diagnosed incidences for boys, girls, and all children declined from 1998 to 2007. Furthermore, there were declining trends both in medical costs and annual medical care visits during the study period. CONCLUSION: This is the first nationwide population-based study to indicate the declining trends in newly diagnosed rate, medical care visits, and medical costs for pediatric urolithiasis. These findings help to quantify and establish the burden of pediatric urolithiasis. These findings help to quantify and establish the burden of medical care for pediatric urolithiasis and to further refine the medical policy.

Sperm quality assessment via separation and sedimentation in a microfluidic device.

A major reason for infertility is due to male factors, including the quality of spermatozoa, which is a primary factor and often difficult to assess, particularly the total sperm concentration and its motile percentage. This work presents a simple microfluidic device to assess sperm quality by quantifying both total and motile sperm counts. The key design feature of the microfluidic device is two channels separated by a permeative phase-guide structure, where one channel is filled with raw semen and the other with pure buffer. The semen sample was allowed to reach equilibrium in both chambers, whereas non-motile sperms remained in the original channel, and roughly half of the motile sperms would swim across the phase-guide barrier into the buffer channel. Sperms in each channel agglomerated into pellets after centrifugation, with the corresponding area representing total and motile sperm concentrations. Total sperm concentration up to 10(8) sperms per ml and motile percentage in the range of 10-70% were tested, encompassing the cutoff value of 40% stated by World Health Organization standards. Results from patient samples show compact and robust pellets after centrifugation. Comparison of total sperm concentration between the microfluidic device and the Makler chamber reveal they agree within 5% and show strong correlation, with a coefficient of determination of R(2) = 0.97. Motile sperm count between the microfluidic device and the Makler chamber agrees within 5%, with a coefficient of determination of R(2) = 0.84. Comparison of results from the Makler Chamber, sperm quality analyzer, and the microfluidic device revealed that results from the microfluidic device agree well with the Makler chamber. The sperm microfluidic chip analyzes both total and motile sperm concentrations in one spin, is accurate and easy to use, and should enable sperm quality analysis with ease.

Direct characterization of motion-dependent parameters of sperm in a microfluidic device: proof of principle.

BACKGROUND: Semen analysis is essential for evaluating male infertility. Besides sperm concentration, other properties, such as motility and morphology, are critical indicators in assessing sperm quality. Nevertheless, rapid and complete assessment of these measures still presents considerable difficulty and involves a range of complex issues. Here we present a microfluidic device capable of quantifying a range of properties of human sperm via the resistive pulse technique (RPT). METHODS: An aperture, designed as a long channel, was used to allow the quantification of various properties as sperm swam through. RESULTS: The time trace of the voltage drop across the aperture during sperm passage contained a wealth of information: the sperm volume was presented by the amplitude of the induced pulse, the swim velocity was evaluated via the duration, and the beat frequency was calculated from the voltage undulation superposed on the pulse signal. The RPT measurement of swim velocity and beat frequency showed a correlation with the same observation in a microscope (R(2) = 0.94 and 0.70, respectively). CONCLUSIONS: The proposed proof of principle enables substantial quantification of the motion-dependent properties of sperm. Because this approach requires only a current/voltage source and data analysis, it is economically advantageous compared with optical methods for characterizing sperm motion. Furthermore, this approach may be used to characterize sperm morphology.

The activation of peripheral 5-HT1A receptors can inhibit seminal vesicle contraction: an in vivo animal study.

OBJECTIVES: To elucidate the differential effects of stimulating various peripheral 5-HT receptor subtypes on the contractile response of seminal vesicles (SVs) induced by electrical stimulation (ES). METHODS: Male Wistar rats (aged 12-14 weeks) were prepared as our previously established model, which allows an intraarterial injection of test agents to directly act on SV. Four selective 5-HT agonists-8-OH-DPAT (5-HT1A), 5-nonyloxytryptamine (5-HT1B), BW723C86 (5-HT2B), and MK-212 (5-HT2C)-were injected at various concentrations (from 10(-8) to 10(-4) mmol/kg). After an injection, the SV contractile response was recorded after ES of lesser splanchnic nerve was applied. Relationships between the concentration of an agonist and its effect on SV contraction were plotted and analyzed. RESULTS: The peripheral injection of 5-HT1A agonist had a dose-dependent inhibitory effect on SV contraction and could achieve an inhibition of >50%; the IC50 was 3.16x10(-6) mmol/kg. No significant effects were observed with the peripheral injection of 5-HT1B, 5-HT2B, or 5-HT2C agonist. CONCLUSIONS: Our in vivo animal study shows that the activation of peripheral 5-HT1A receptors can inhibit ES-induced SV contraction, whereas the activation of peripheral 5-HT1B, 5-HT2B, or 5-HT2C receptors has no significant effect. The results suggest that the peripheral 5-HT pathway is a potential therapeutic target of the treatment for premature ejaculation.

Determination of human penile electrical resistance and implication on safety for electrosurgery of penis.

INTRODUCTION: Electrosurgery has been a surgical application since the late 19th century. Although many urologists take this daily application for granted, the effects of electrical treatment on penile nerves and vessels have not been well documented. AIM: To investigate the electrical characteristics of the penis and erectile tissues and to discover the potential hazards of electrosurgery on the penis. METHODS: Measurement of the electrical characteristics of three human penises in order to create models to analyze the effect of electricity on penile nerves and vessels. MAIN OUTCOME MEASURES: Electrical resistivity of the penile shaft, electrical current density, and electric field strength on penile nerves and vessels, proportion of generated heat on the penis and electrical current density of the electrosurgery return electrode. RESULTS: Electrical resistivity (ρ) of the penile shaft is 127.14 Ω · cm at 500 kHz. Electrical current density (J) of the penis shaft is 71.06 mA/cm(2) , nerve (60.23 mA/cm(2) ), vessel (67.93 mA/cm(2) ), and return electrode (2.11 mA/cm(2) ). Electrical field strength (E) of the whole penis shaft is 9.03 volt/cm. The proportion of generated heat on the penis is four times as much as on other body parts of the circuit. CONCLUSIONS: Potential and subclinical injury to erectile tissue caused by electrosurgery on the penis cannot be underestimated. The injury mechanism can be attributed to a thermal (electrical current) effect and a nonthermal (mainly electrical field) effect. Ways to avoid the electrosurgical injury are: using less power (W)/electrical field and less time, biopolar electrosurgery confining the injured area, ligation to achieve hemostasis, and new laser technologies.

Parasympathetic influence plays an independent and significant role in inducing the contraction of the seminal vesicle of the rat.

OBJECTIVES: The role of the parasympathetic pathway in seminal vesicle (SV) contraction has not been well described. The purpose of this study was to study parasympathetic effects, the dominant muscarinic receptors subtype(s), and nitric oxide (NO) effects for SV contraction. METHODS: In vivo, SV pressure of mature male Wistar rats were recorded after electric stimulation (ES) of each pelvic nerve (PN; parasympathetic pathway) alone; bilateral PNs simultaneously, the L6 and S1 branches of the left PN; the left PN after ablation of sympathetic influence; the lesser splanchnic nerve (LSN) after ablation of parasympathetic influence; and the LSN after pretreatment of 4 muscarinic receptor antagonists or a NO donor-3-Morpholinosydnonimine (SIN-1). RESULTS: ES to the left PN caused frequency-dependent SV contraction, with similar results after ES to the right PN and bilateral PNS. ES to the L6 branch of the left PN caused significantly greater SV response than to the S1 branch. Ablation of sympathetic influence did not affect SV response to parasympathetic stimulation and vice versa. The inhibitory effects of 4-DAMP (M3 antagonist) and atropine (nonselective muscarinic antagonist) on SV response to ES were similar and significantly greater than those of pirenzepine (M1 antagonist) and methoctramine (M2 antagonist). Pretreatment of SIN-1 partially suppressed the SV response of ES to left PN. CONCLUSIONS: ES via the parasympathetic pathway independently induces contraction of rat SV; NO partially suppresses the SV pressure response to parasympathetic ES.

Feasability of a novel audio-video sexual stimulation system: an adjunct to the use of penile duplex Doppler ultrasonography for the investigation of erectile dysfunction.

INTRODUCTION: Penile color Doppler ultrasonography (CDUS) with pharmacotesting has become an important tool for evaluating vascular erectile dysfunction (ED), and audio-visual sexual stimulation (AVSS) has been suggested to be helpful in assisting the performance of CDUS during the examination. AIM: To investigate the feasibility of using a novel, remotely controllable AVSS system to assist CDUS. METHODS: This prospective randomized cross-over study recruited 60 consecutive ED patients. Each patient received three randomized sessions of CDUS under different conditions-AVSS, intracavernous injection (ICI) of alprostadil 20 microgram, or AVSS plus ICI. Clinical responses (rigidity) and penile vascular parameters including peak systolic velocity (PSV), end diastolic velocity (EDV), and resistive index (RI) were measured. At the end of the study, patients were asked about how they perceived the AVSS system in generating sexual arousal. MAIN OUTCOME MEASURES: PSV, EDV, RI, and rigidity. RESULTS: Fifty-eight ED patients (aged 21-79) underwent 174 sessions of CDUS. The mean PSV and maximal rigidity of patients under ICI alone were significantly greater than those of patients under AVSS alone (48.25 ± 22.78 vs. 36.54 ± 23.25 cm/second and 65.00 ± 23.93% vs. 43.28 ± 31.79%, respectively; both P < 0.05). The mean PSV of patients under AVSS plus ICI (55.38 ± 28.81 cm/second) was significantly greater than that of patients under ICI alone (P < 0.05), while the mean maximal rigidity (72.50 ± 22.03%) was only marginally greater (P = 0.082). EDV or RI was of no significant difference among the different conditions. Ultrasonographic diagnoses of ED under different conditions varied substantially. Fifty-four (93%) patients considered the AVSS system "very satisfactory" or "satisfactory" in evoking sexual arousal. CONCLUSIONS: The novel, remotely controllable AVSS system is well accepted by patients and, in conjunction with ICI, helps to produce higher PSV for patients undergoing CDUS.