Mingzhen Yuan

Improving outcomes of acute kidney injury using mouse renal progenitor cells alone or in combination with erythropoietin or suramin

IntroductionSo far, no effective therapy is available for acute kidney injury (AKI), a common and serious complication with high morbidity and mortality. Interest has recently been focused on the potential therapeutic effect of mouse adult renal progenitor cells (MRPC), erythropoietin (EPO) and suramin in the recovery of ischemia-induced AKI. The aim of the present study is to compare MRPC with MRPC/EPO or MRPC/suramin concomitantly in the treatment of a mouse model of ischemia/reperfusion (I/R) AKI.MethodsMRPC were isolated from adult C57BL/6-gfp mice. Male C57BL/6 mice (eight-weeks old, n = 72) were used for the I/R AKI model. Serum creatinine (Cr), blood urea nitrogen (BUN) and renal histology were detected in MRPC-, MRPC/EPO-, MRPC/suramin- and PBS-treated I/R AKI mice. E-cadherin, CD34 and GFP protein expression was assessed by immunohistochemical assay.ResultsMRPC exhibited characteristics consistent with renal stem cells. The features of MRPC were manifested by Pax-2, Oct-4, vimentin, α-smooth muscle actin positive, and E-cadherin negative, distinguished from mesenchymal stem cells (MSC) by expression of CD34 and Sca-1. The plasticity of MRPC was shown by the ability to differentiate into osteoblasts and lipocytes in vitro. Injection of MRPC, especially MRPC/EPO and MRPC/suramin in I/R AKI mice attenuated renal damage with a decrease of the necrotic injury, peak plasma Cr and BUN. Furthermore, seven days after the injury, MRPC/EPO or MRPC/suramin formed more CD34+ and E-cadherin+ cells than MRPC alone.ConclusionsThese results suggest that MRPC, in particular MRPC/EPO or MRPC/suramin, promote renal repair after injury and may be a promising therapeutic strategy.

The vascular and neurogenic factors associated with erectile dysfunction in patients after pelvic fractures

ABSTRACT Erectile dysfunction (ED) is a common complication of pelvic fractures. To identify the vascular and neurogenic factors associated with ED, 120 patients admitted with ED after traumatic pelvic fracture between January 2009 and June 2013 were enrolled in this study. All patients answered the International Index of Erectile Function (IIEF-5) questionnaire. Nocturnal penile tumescence (NPT) testing confirmed the occurrence of ED in 96 (80%) patients on whom penile duplex ultrasound and neurophysiological testing were further performed. Of these ED patients 29 (30%) were demonstrated only with vascular abnormality, 41 (42.7%) were detected only with neural abnormality, 26 (27.1%) revealed mixed abnormalities. Of the 55 patients (29+26) with vascular problems, 7 patients (12.7%) with abnormal arterial response to intracavernous injection of Bimix (15mg papaverine and 1mg phentolamine), 31 (56.4%) with corporal veno-occlusive dysfunction and 17 (30.9%) had both problems. Of the 67 (41+26) patients with abnormal neurophysiological outcomes, 51 (76.1%) with abnormal bulbocavernosus reflex (BCR), 20 (29.9%) with pathological pudendal nerve evoked potentials (PDEPs) and 25 (37.3%) with abnormal posterior tibial somatosensory nerve evoked potentials (PTSSEPs). Our observation indicated that neurogenic factors are important for the generation of ED in patients with pelvic fracture; venous impotence is more common than arteriogenic ED.

High expression of MICA in human kidney cancer tissue and renal cell carcinoma lines.

The overall incidence and mortality of renal cell carcinoma (RCC), the most common kidney cancer, are steadily increasing for reasons that are not fully explained. Our aim was to explore the expression of membrane MHC class I chain-related gene A (mMICA) in human RCC cell lines and tissue specimens, and to determine expression of soluble MICA (sMICA) in serum of patients with renal cell carcinoma, we used flow cytometry (FCM) and immunohistochemistry as well as an enzyme linked immunosorbent assay (ELISA) . The results showed that percentage of mMICA expression was significantly increased in human kidney cancer tissues and RCC cell lines (786-O and Ketr-3) than that in healthy adults and human embryonic kidney 293 (HEK293) cell line individuality (P<0.05). sMICA content in healthy adults was negative, but in renal cancer patients was significantly elevated (P<0.05). Our research showed that high expression of MICA in human kidney cancer, this results show that MICA might serve as potential tumor-associated antigen (TAA) in RCC.

Significance of platelet distribution width as a severity marker of erectile dysfunction

Mean platelet volume (MPV) and Platelet distribution width (PDW) are potential markers in platelet activation. In present study, we aimed to evaluate MPV and PDW as potential severity markers for those patients who are complaining erectile dysfunction (ED). A total of 358 participants were enrolled in this study. The whole cohort was asked to complete the International Index of Erectile Function‐5 (IIEF‐5) questionnaire. The participants were classified into 3 groups: control group (n = 120), mild ED (n = 118) and severe ED (n = 120). We found in our cohort MPV and PDW were significantly higher in both mild ED group and severe ED group than control group (9.24 ± 0.70 and 9.71 ± 0.80 versus 8.56 ± 0.62 for MPV; 14.48 ± 1.29 and 14.98 ± 1.60 versus 12.86 ± 1.13 for PDW respectively). The MPV and PDW increased as the disease progressed. In the mild and severe ED groups, a significant inverse correlation was detected between the mean values of IIEF‐5 score and PDW. Furthermore, in the receiver operating characteristic curve analysis, the area under the curve of the MPV and PDW to predict severe ED was 0.818 and 0.848 respectively. Our study establishes a dose‐dependent association between the PDW and ED. Therefore, the PDW can serve as a potential marker for predicting the severity of ED.

Regulation Roles of MICA and NKG2D in Human Renal Cancer Cells

OBJECTIVE Our aim was to investigation the roles of MHC class I chain-related gene A(MICA) and natural killer cell group 2D(NKG2D) in human renal cancer cells. MATERIALS AND METHODS The expression of membrane MICA (mMICA) on renal cells and NKG2D on NK cells were detected by flow cytometry (FCM); the content of sMICA were detected by enzyme linked immunosorbent assay (ELISA) and the distribution of mMICA on renal tumor tissues by immunohistochemistry; the interaction between MICA and NKG2D was observed by antibody closed method. RESULTS Our results showed that the expression of mMICA in renal cancer tissues was significantly higher than in controls, where the soluble MICA was not expressed. Cytotoxic activity of NK cells was significantly reduced after exposure to NKG2D and MICA antibodies (P<0.05), and serum containing sMICA can obviously lower the function of NKG2D (P<0.05). CONCLUSIONS The interaction of mMICA and NKG2D play important roles in mediation of cytotoxicity of NK cells in RCC. On the other hand, sMICA may mediate tumor immune escape through down- regulated NKG2D expression.

Mean platelet volume might be an effective indicator of arterial erectile dysfunction

The aim of our study was to investigate the role of platelet parameters including mean platelet volume (MPV) and platelet count (PC) in the pathogenesis of penile arteriogenic erectile dysfunction (ED) and to evaluate the association between the platelet parameters and arteriogenic ED. There were 244 patients with ED (based on the International Index of Erectile Function [IIEF]-5 ≤21) and 60 healthy controls (IIEF-5 >21) enrolled. All participants were asked to undergo a laboratory examination, and penile vascular function was evaluated using penile color Doppler ultrasonography (pDUS). Among these ED patients, 24 patients with no abnormality on nocturnal penile tumescence (NPT) and 84 with normal vasculature or mixed vascular abnormalities were excluded. The other patients were classified into three groups as follows: control (n = 60), arteriogenic ED (n = 99), and venous leakage (n = 37) groups. MPV and PC were significantly higher in the arteriogenic ED group compared with the venous and control groups (P < 0.05). Receiver operating characteristic curve analysis revealed that the area under the curve for MPV to predict arteriogenic ED was 0.707. MPV ≥9.65 fl was recognized as a cut-off value for potential arteriogenic ED (sensitivity: 47.5%; specificity: 91.7%). A significant inverse correlation was detected between MPV and 10-min peak systolic velocity (PSV) (r = −0.34; P < 0.001) in the arteriogenic ED group. These findings suggest that the MPV might be a powerful indicator to predict and diagnose arteriogenic ED, and MPV may be a marker for ED when using pDUS.

Reduced bladder responses to capsaicin and GSK1016790A in retired-breeder female rats with diminished volume sensitivity

Literature documents an age-related reduction of bladder sensory function. Transient receptor potential vanilloid (TRPV)1 or TRPV4 channels have been implicated in bladder mechanotransduction. To investigate contributions of TRPV1 or TRPV4 to the age-related reduction of bladder sensory function, bladder responses to capsaicin (CAP; TRPV1 agonist) and GSK-1016790A (GSK; TRPV4 agonist) in retired breeder (RB; 12-15 mo) and young adult (2-3 mo) female rats were compared using multiple methods. Metabolic cage and continuous infusion cystometry [cystometrogram (CMG)] recordings revealed that RB rats exhibit larger bladder capacity and lower voiding frequency. RB rats also have a greater intravesical pressure threshold for micturition; however, the voiding contraction strength was equivalent to that in young rats. CAP (1 μM) or GSK (20 nM) administered intravesically evoked smaller changes in all CMG parameters in RB rats. In vitro, CAP (1 μM) or GSK (20 nM) evoked smaller enhancement of bladder strip contractions, while the muscarinic receptor agonist carbachol (at 100, 300, and 1,000 nM) elicited greater amplitude contractions in RB rats. Patch-clamp recording revealed smaller CAP (100 nM) induced inward currents in bladder primary sensory neurons, and Ca2+ imaging revealed smaller GSK (20 nM) evoked increases in intracellular Ca2+ concentration in urothelial cells in RB rats. These results suggest that RB rats have a decreased bladder sensory function commonly observed in elderly women, and could be used as an animal model to study the underling mechanisms. Reduced functional expression of TRPV1 in bladder afferents or reduced functional expression of urothelial TRPV4 may be associated with the diminished sensory function.

Construction of engineered corpus cavernosum with primary mesenchymal stem cells in vitro

Various methods have been used to reconstruct the penis. The objective of this study was to investigate the feasibility of constructing engineered corpus cavernosum with primary mesenchymal stem cells (MSCs) in a rabbit model in vitro. Acellular corporal matrices (ACMs) were obtained from adult rabbit penile tissues through an established decellularization procedure. MSCs were separated, purified, and then seeded on ACMs to construct engineered corpus cavernosum. The seeded ACMs were subsequently cultured in an incubator for 14 days. Histological analyses showed that MSCs seeded on the ACMs had proliferated and were well distributed. Detection of CD31, vWF, smooth muscle actin (SMA), and myosin protein as well as vWF and myosin mRNA revealed that the MSCs had differentiated into endothelial cells and smooth muscle cells. In addition, cell morphology of the engineered corpus cavernosum was directly observed by transmission electron microscopy. This study demonstrated that engineered corpus cavernosum could be successfully constructed using primary MSCs in vitro. This technology represents another step towards developing engineered corpus cavernosum in vitro.

Significance of penile hypersensitivity in premature ejaculation

To assess the correlation between penile hypersensitivity and premature ejaculation (PE), a total of 420 consecutive subjects attending our andrologic clinic for suspected PE were enrolled. The entire cohort was asked to complete the self-report intravaginal ejaculation latency time (IELT) by stopwatch. According to the IELT, the subjects were classified into 3 groups. Vibratory thresholds were recorded at the glans penis and penile shaft using a biothesiometer. We found that vibratory thresholds in the glans penis and penile shaft were significantly lower in both mild and severe PE group than in the control group (3.81 ± 0.57 and 3.54 ± 0.43 vs 4.73 ± 0.77 for glans penis p = 0.000; 3.64 ± 0.52 and 3.37 ± 0.50 vs 4.62 ± 0.69 for penile shaft p = 0.002). The vibratory threshold decreased as the disease aggravated. In the mild and severe PE groups, a significant positive correlation was detected between the mean values of IELT and the vibratory thresholds. Furthermore, in the receiver operating characteristics curve analysis, the area under the curve of the glans penis and penile shaft vibratory thresholds predicting severe PE were 0.852 and 0.893 respectively. Our study established a dose-dependent association between penile vibratory threshold and PE. Therefore, the vibratory threshold can serve as a potential marker for predicting the severity of PE.

The application of laparoscopic Doppler ultrasound during laparoscopic varicocelectomy in infertile men.

The aim of this study is to evaluate the benefits of laparoscopic Doppler ultrasound (LDU) application during laparoscopic varicocelectomy (LV), and to compare the surgical outcomes and complications between LDU-assisted LV (LDU-LV) and conventional LV for infertile patients with varicoceles; 147 infertile patients were randomly divided into two groups. Operative and postoperative parameters, semen parameters, and the pregnancy rate were compared. There were no differences in baseline demographics. The operative time was significantly longer in LDU-LV group than LV group. The incidence of postoperative hydrocele was 1.4% (1/72) in LDU-LV group versus 10.7% (8/75) in LV group, which showed a significant difference (P < 0.05). However, other surgical outcomes, such as postoperative hospital stay, postoperative recurrence, and testicular atrophy, were similar between the two groups. Sperm concentration and sperm motility were significantly increased in both groups at 3, 6, and 12 months after surgery (P < 0.01), and they were higher in LDU-LV than LV group in 12 months after surgery (34.21 ± 6.36 vs 29.99 ± 6.04 for concentration, P < 0.05; 40.72 ± 8.12 vs 37.31 ± 6.12 for motility, P < 0.05). Sperm morphology was comparable between the two groups. The pregnancy rate showed no significant difference (44.4% of the LDU-LV vs 37.3% of the LV, P > 0.05). In conclusion, compared with LV, LDU-LV could safely and effectively ligate all spermatic veins and preserve spermatic arteries without leading to high varicocele recurrence and postoperative hydrocele. Given the benefits that sperm counts as well as sperm motility favoring LDU-LV, we recommend that LDU should be routinely used as an effective tool to improve outcomes and safety of laparoscopic varicocelectomy.