Two-micron （thulium） laser resection of the prostate- tangerine technique： a new method for BPH treatment

Two-micron （thulium） laser resection of the prostate-tangerine technique （TmLRP-TT） is a transurethral procedure that uses a thulium laser fiber to dissect whole prostatic lobes off the surgical capsule, similar to peeling a tangerine. We recently reported the primary results. Here we introduce this procedure in detail. A 70-W, 2-um （thulium） laser was used in continuous-wave mode. We joined the incision by making a transverse cut from the level of the verumontanum to the bladder neck, making the resection sufficiently deep to reach the surgical capsule, and resected the prostate into small pieces, just like peeling a tangerine. As we resected the prostate, the pieces were vaporized, sufficiently small to be evacuated through the reseetoscope sheath, and the use of the mechanical tissue morcellator was not required. The excellent hemostasis of the thulium laser ensured the safety of TmLRP-TT. No patient required blood transfusion. Saline irrigation was used intraoperatively, and no case of transurethral resection syndrome was observed. The bladder outlet obstruction had clearly resolved after catheter removal in all cases. We designed the tangerine technique and proved it to be the most suitable procedure for the use of thulium laser in the treatment of benign prostatic hyperplasia （BPH）. This procedure, which takes less operative time than standard techniques, is safe and combines efficient cutting and rapid organic vaporization, thereby showing the great superiority of the thulium fiber laser in the treatment of BPH. It has been proven to be as safe and efficient as transurethral resection of the prostate （TURP） during the 1-year follow-up.

Characteristic pattern of human prostatic growth with age

Aim: To study the characteristic pattern of the age-related growth of the human prostate gland. Methods: The volume (weight) of the prostate in 1,601 males, aged from newborn to 92 years, was determined by Bultrasonography. Results: Prostatic volume determination by B-ultrasonography in 1601 males (1301 normal subjects and 300 BPH patients) pointed out that the age-stratified growth of human prostate could be categorized into 4 life stages: (1) the first slow growing phase (from newborn to 9 years): the prostate grows slowly at a rate of 0.14g per year; (2) the first rapid growing phase (from 10 to 30 years): the prostate grows at a rate of 0.84 g per year; (3) the second slow growing phase (from 30 to 50 years), the prostate grows at a rate of 0.21 g per year; (4) the second rapid growing phase (from 50 to 90 years): the prostate grows at one of the following rates: in one group the growth rate is of 0.50 g per year and in the other 1.20 g per year, leading to benign prostatic hyperplasia (BPH). Conclusion: The volumes of the prostate are different in different age groups and it grows with age at different rates in four life phases. The prostate growth in phases can be expressed by the following equation: Y=19.36+1.36X'-0.58X'2+0.33X'3, where Y=prostate volume, X=age (up to 70 years), X'=(X-35.5)/10. (Asian JAndrol 2002 Dec; 4: 269-271)

Tumor formation of prostate cancer cells influenced by stromal cells from the transitional or peripheral zones of the normal prostate

This study was designed to investigate the different involvements of prostatic stromal cells from the normal transitional zone(TZ)or peripheral zone(PZ)in the carcinogenesis of prostate cancer(PCa)epithelial cells(PC-3)in vitro and in vivo co-culture models.Ultra-structures and gene expression profiles of primary cultures of human prostatic stromal cells from the normal TZ or PZ were analyzed by electron microscopy and microarray analysis.In vitro and in vivo co-culture models composed of normal TZ or PZ stromal cells and human PCa PC-3 cells were established.We assessed tumor growth and weight in the in vivo nude mice model.There are morphological and ultra-structural differences in stromal cells from TZ and PZ of the normal prostate.In all,514 differentially expressed genes were selected by microarray analysis;483 genes were more highly expressed in stromal cells from TZ and 31 were more highly expressed in those from PZ.Co-culture with PZ stromal cells and transforming growth factor-β1(TGF-β1)increased the tumor growth of PC-3 cells in vitro and in vivo,as well as Bcl-2 expression.On the other hand,stromal cells of TZ suppressed PC-3 cell tumor growth in the mouse model.We conclude that ultra-structures and gene expression differ between the stromal cells from TZ or PZ of the normal prostate,and stroma-epithelium interactions from TZ or PZ might be responsible for the distinct zonal localization of prostate tumor formation.

An overview of prostate diseases and their characteristics specific to Asian men

In this paper, we reviewed the features of common prostate diseases, such as benign prostatic hyperplasia （BPH）, prostate cancer （PCa） and chronic prostatitis （CP） that are specific to Asian men. Compared to the Westerners, Asians exhibit particular characteristics of prostate diseases. Through summarizing the epidemiology, symptomatology, diagnostics and therapeutics of these diseases, we find that Asians have a lower incidence of PCa than whites, but the incidences of BPH and CP are similar. Asian men with CP often suffer from fewer disease sites, but have a higher frequency of pain during urination rather than after sexual climax. Prostate-specific antigen （PSA） is a widely used marker for the diagnosis of PCa in both Asian and Western countries. Although the PSA level may be lower in Asians, the threshold used is based on whites. After reviewing the treatments available for these diseases, we did not find a fundamental difference between Asians and whites. Furthermore, the selection for the most appropriate treatment based on the individual needs of patients remains a challenge to urologists in Asia. After considering the traits of prostate diseases that are specific to Asian men, we hope to pave the way for the development of specific diagnostic and therapeutic strategies targeted specifically to Asian men.

nfluence of immune inflammation on androgen receptor expression in benign prostatic hyperplasia tissue

This study was designed to investigate the association between immune inflammation and androgen receptor （AR） expression in benign prostatic hyperplasia （BPH）. We retrospectively analyzed 105 prostatectomy specimens. An immune inflammation score for each specimen was defined by combining three immunohistochemical markers （CD4, CD8 and CD20）. The immunohistochemical markers were CD4 and CD8 for T lymphocytes, CD20 for B lymphocytes and AR antibody for the AR in BPH samples. Rates of CD4, CD8, CD20 and AR expression in BPH were 20 （19.0%）, 21 （20.0%）, 101 （96.2%） and 48 （45.7%）, respectively. Total prostate volume （TPV） was higher in the immune inflammation group than in the non-immune inflammation group （62.7 ml vs. 49.2 ml, t=-2.482, P〈0.05）. Patients in the immune inflammation group had a higher serum prostate-specific antigen （PSA） than those in the non-inflammation group （7.5 ng m1-1 vs. 5.4 ng m1-1, t=-2.771, P〈0.05）. Specifically, the immune inflammation group showed a higher rate of AR expression than the non-inflammation group （56.1% vs. 28.2%, χ2=7.665, P〈0.05）. Our study revealed a strong association between immune inflammation and TPV, serum PSA and AR expression in BPH tissue. Prostate hyperplasia caused by an immune inflammatory process may contribute to BPH progression over time. Therefore, the inflammatory response involved in BPH may be a prime therapeutic target.

Stroma-epithelium crosstalk in prostate cancer

The critical role played by stroma-epithelium crosstalk in carcinogenesis and progression of prostate cancer has been increasingly recognized. These interactions are mediated by a variety of paracrine factors secreted by cancer cells and/or stromal cells. In human prostate cancer, reactive stroma is characterized by an increase in myofibroblasts and a corresponding amplification of extracellular matrix production and angiogenesis. Permanent genetic mutations have been reported in stromal cells as well as in tumour cells. Transforming growth factor-J3, vascular endothelial growth factor, platelet-derived growth factor and fibroblast growth factor signalling pathways are involved in the process of angiogenesis, whereas hepatocyte growth factor, insulin-like growth factor-l, epidermal growth factor, CXC12 and Interleukin-6 play active roles in the progression, androgen-independent conversion and distal metastasis of prostate cancer. Some soluble factors have reciprocal interactions with androgens and the androgen receptor （AR）, and can even activate AR in the absence of the androgen ligand. In this article, we review the complex interactions between cancer cells and the surrounding microenvironment, and discuss the potential therapeutic targets in the stromal compartment of prostate cancer.

Chimeric molecules facilitate the degradation of androgen receptors and repress the growth of LNCaP cells

Post-translational degradation of protein plays an important role in cell life. We employed chimeric molecules （dihydrotestosterone-based proteolysis-targeting chimeric molecule [DHT-PROTAC]） to facilitate androgen receptor （AR） degradation via the ubiquitin-proteasome pathway （UPP） and to investigate the role of AR in cell proliferation and viability in androgen-sensitive prostate cancer cells. Western blot analysis and immunohistochemistry were applied to analyse AR levels in LNCaP cells after DHT-PROTAC treatment. Cell counting and the 3-（4,5-dimethylthiazol-2-yl）-2,5- diphenyl tetrazolium bromide （MTT） cell viability assay were used to evaluate cell proliferation and viability after AR elimination in both LNCaP and PC-3 cells. AR was tagged for elimination via the UPP by DHT-PROTAC, and this could be blocked by proteasome inhibitors. Degradation of AR depended on DHT-PROTAC concentration, and either DHT or an ALAPYIP-（arg）8 peptide could compete with DHT-PROTAC. Inhibition of cell proliferation and decreased viability were observed in LNCaP cells, but not in PC-3 or 786-0 cells after DHT-PROTAC treatment. These data indicate that AR elimination is facilitated via the UPP by DHT-PROTAC, and that the growth of LNCaP cells is repressed after AR degradation.

Antitumor immunity by a dendritic cell vaccine encoding secondary lymphoid chemokine and tumor lysate on murine prostate cancer

Aim： To investigate the antitumor immunity by a dendritic cell （DC） vaccine encoding secondary lymphoid chemokine gene and tumor lysate on murine prostate cancer. Methods： DC from bone marrow of C57BL/6 were transfected with a plasmid vector expressing secondary lymphoid chemokine （SLC） cDNA by Lipofectamine2000 liposome and tumor lysate. Total RNA extracted from SLC＋lysate-DC was used to verify the expression of SLC by reverse transcriptase-polymerase chain reaction （RT-PCR）. The immunotherapeutic effect of DC vaccine on murine prostate cancer was assessed. Results： We found that in the prostate tumor model of C57BL/6 mice, the adminstration of SLC＋lysate-DC inhibited tumor growth most significantly when compared with SLC-DC, lysate-DC, DC or phos- phate buffer solution （PBS） counterparts （P 〈 0.01）. Immunohistochemical fluorescent staining analysis showed the infiltration of more CD4＋, CD8＋ T cell and CD11c＋ DC within established tumor treated by SLC＋lysate-DC vaccine than other DC vaccines （P 〈 0.01）. Conclusion： DC vaccine encoding secondary lymphoid chemokine and tumor lysate can elicit significant antitumor immunity by infiltration of CD4＋, CD8＋ T cell and DC, which might provide a potential immunotherapy method for prostate cancer.

Differences in phenotype and gene expression of prostate stromal cells from patients of varying ages and their influence on tumour formation by prostate epithelial cells

Prostate cancer （PCa） is an age-related disease, and the stromal microenvironment plays an important role in prostatic malignant progression. However, the differences in prostate stromal cells present in young and old tissue are still obscure. We established primary cultured stromal cells from normal prostatic peripheral zone （PZ） of donors of varying ages and found that cultured stromal cells from old donors （PZ-old） were more enlarged and polygonal than those from young donors （PZ-young）. Furthermore, based on immunocytochemical and ultrastructural analysis, the components of stromal cells changed from a majority of fibroblasts to a mixture of fibroblasts and myofibroblasts with increasing donor age. Using a three-dimensional in vitro culture system, we found that PZ-old stromal cells could enhance the proliferation, migration and invasion of cocultured benign BPH-1 and PC-3 cells. Using an in vivo tissue recombination system, we also found that PZ-old stromal cells are more effective than PZ-young cells in promoting tumour formation by BPH-1 cells of high passage（〉100） and PC-3 cells. To probe the possible mechanism of these effects, we performed cDNA microarray analysis and profiled 509 upregulated genes and 188 downregulated genes in PZ-old cells. Among the changed genes, we found genes coding for a subset of paracrine factors that are capable of influencing adjacent epithelial cells; these include hepatocyte growth factor （HGF）, fibroblast growth factor 5 （FGF5）, insulin-like growth factor 2 （IGF2）, insulin-like growth factor-binding protein 4 （IGFBP4）, IGFBP5 and matrix metallopeptidase 1 （MMP1）. Changes in the expression of these genes were further confirmed by quantitative real-time polymerase chain reaction （PCR）, Western blotting and enzyme-linked immunosorbent assays. Overall, our findings indicate that stromal cells from prostate PZ of old donors are more active than similar cells from young donors in promoting the malignant process of adjacent epithelial cells. This finding hints at a new potential strategy for the prevention of PCa.

In vitro comparison of the vaporesection of human benign prostatic hyperplasia using 70-and 120-W 2μm lasers

The purpose of the current ex vivo study was to compare the speed of vaporesection of human prostatic tissue with benign prostatic hyperplasia （BPH） and the depth of tissue damage using 70- and 120-W 2-tim laser devices. Fresh prostatic tissue specimens were obtained from five patients by open prostatectomy, and were divided into separate groups （70 and 120 W） based on the energy of the laser output （70 and 120 W, respectively）. The vaporesection speed, coagulation zone depth and the necrotic tissue layer in the prostatic tissue were evaluated. The current result showed that the speeds （mean±s.d.） of vaporesection were 5.21±0.66 and 10.39±1.15 g/5 min for the 70 and 120 W groups, respectively （P=0.000）. There was no difference in the depth of necrosis/ coagulation （0.98±0.1310.30±0.09 and 0.99±0.12/0.31±0.08 mm） for the 70 and 120 W groups, respectively. In conclusion, both 70- and 120-W 2μm laser devices had superficial tissue damage during the vaporesection of human prostate tissue; moreover, the 120-W laser offers a higher vaporesection speed than the 70-W laser.

Androgen receptors expressed by prostatic stromal cells obtained from younger versus older males exhibit opposite roles in prostate cancer progression

Aging is a major risk factor for prostate cancer （PCa）, and prostatic stromal cells may also promote PCa progression. Accordingly, stromal cells do not equally promote PCa in older males and younger males. Therefore, it is also possible that the expression of androgen receptors （ARs） by prostatic stromal cells in older versus younger males plays different roles in PCa progression. Using a gene knockdown technique and coculture system, we found that the knockdown of the AR in prostatic stromal cells obtained from younger males could promote the invasiveness and metastasis of cocultured PC3/LNCaP cells in vitro. By contrast, the invasiveness and metastasis of LNCaP cells was inhibited when cocultured with prostatic stromal cells from older males that when AR expression was knocked down. Moreover, after targeting AR expression with small hairpin RNA （shRNA）, matrix metalloproteinase （MMP） expression in stromal cells was observed to increase in the younger group, but decreased or remained unchanged in the older group. One exception, however, was observed with MMP9. In vivo, after knocking down AR expression in prostatic stromal cells, the incidence of metastatic lymph nodes was observed to increase in the younger age group, but decreased in the older age group. Together, these data suggest that the AR in prostatic stromal cells played opposite roles in PCa metastasis for older versus younger males. Therefore, collectively, the function of the AR in prostatic stromal cells appears to change with age, and this may account for the increased incidence of PCa in older males.

The diverse and contrasting effects of using human prostate cancer cell lines to study androgen receptor roles in prostate cancer

The androgen receptor （AR） plays an important role in the development and progression of prostate cancer （PCa）. Androgen deprivation therapy is initially effective in blocking tumor growth, but it eventually leads to the hormonerefractory state. The detailed mechanisms of the conversion from androgen dependence to androgen independence remain unclear. Several PCa cell lines were established to study the role of AR in PCa, but the results were often inconsistent or contrasting in different cell lines, or in the same cell line grown under different conditions. The cellular and molecular alteration of epithelial cells and their microenvironments are complicated, and it is difficult to use a single cell line to address this important issue and also to study the pathophysiological effects of AR. In this paper, we summarize the different effects of AR on multiple cell lines and show the disadvantages of using a single human PCa cell line to study AR effects on PCa. We also discuss the advantages of widely used epithelium-stroma co-culture systems, xenograft mouse models, and genetically engineered PCa mouse models. The combination of in vitro cell line studies and in vivo mouse models might lead to more credible results and better strategies for the study of AR roles in PCa.

Re-epithelialization resulted from prostate basal cells in canine prostatic urethra may represent the ideal healing method after two-micron laser resection of the prostate

The purpose of this study is to characterize the re-epithelialization of wound healing in canine prostatic urethra and to evaluate the effect of this re-epithelialization way after two-micron laser resection of the prostate （TmLRP）. TmLRP and partial bladder neck mucosa were performed in 15 healthy adult male crossbred canines. Wound specimens were harvested at 3 days, and 1, 2, 3, and 4 weeks after operation, respectively. The histopathologic characteristics were observed by hematoxylin and eosin staining. The expression of cytokeratin 14 （CK14）, CK5, CK18, synaptophysin （Syn）, chromogranin A （CgA）, uroplakin, transforming growth factor-β1 （TGF-β1）, and TGF-β type Ⅱ receptor in prostatic urethra wound were examined by immunohistochemistry and real-time polymerase chain reaction, respectively. Van Gieson staining was performed to determine the expression of collagen fibers in prostatic urethra and bladder neck would. The results showed that the re-epithelialization of the prostatic urethra resulted from the mobilization of proliferating epithelial cells from residual prostate tissue under the wound. The proliferating cells expressed CK14, CK5, but not CK18, Syn, and CgA and re-epithelialize expressed uroplakin since 3 weeks. There were enhanced TGF-β1 and TGF-β type Ⅱ receptor expression in proliferating cells and regenerated cells, which correlated with specific phases of re-epithelialization. Compared with the re-epithelialization of the bladder neck, re-epithelialization of canine prostatic urethra was faster, and the expression of collagen fibers was relatively low. In conclusion, re-epithelialization in canine prostatic urethra resulted from prostate basal cells after TmLRP and this re-epithelialization way may represent the ideal healing method from anatomic repair to functional recovery after injury.

Comparison of diagnostic efficacy between transrectal and transperineal prostate biopsy:a propensity score-matched study

This study compared the diagnostic efficacy of transrectal ultrasound(TRUS)-guided prostate biopsy(TRBx)and transperineal prostate biopsy(TPBx)in patients with suspected prostate cancer(PCa).We enrolled 2962 men who underwent transrectal(n=1216)or transperineal(n=1746)systematic 12-core prostate biopsy.Clinical data including age,prostate-specific antigen(PSA)level,and prostate volume(PV)were recorded.To minimize confounding,we performed propensity score-matching analysis?We measured and compared PCa detection rates between TRBx and TPBx,which were stratified by clinical characteristics and Gleason scores.The effects of clinical characteristics on PCa detection rate were assessed by logistic regression.For all patients,TPBx detected a higher proportion of clinically significant PCa(P<0.001).Logistic regression analyses illustrated that PV had a smaller impact on PCa detection rate of TPBx compared with TRBx.Propensity score-matching analysis showed that the detection rates in TRBx were higher than those in TPBx for patients aged≥80 years(80.4%vs 56.5%,P=0.004)and with PSA level 20.1-100.0 ng ml^-1(80.8%vs 69.1%,P=0.040).In conclusion,TPBx was associated with a higher detection rate of clinically significant PCa than TRBx was;however,because of the high detection rate at certain ages and PSA levels,biopsy approaches should be optimized according to patents'clinical characteristics.

Two-micrometer thulium laser resection of the prostate-tangerine technique in benign prostatic hyperplasia patients with previously negative transrectal prostate biopsy

The 2-1μm thulium laser resection of the prostate-tangerine technique （TmLRP-TT） has been introduced as a minimally invasive treatment for benign prostatic hyperplasia （BPH）. This study was undertaken to assess the clinical efficacy and safety of TmLRP-TT for the treatment of BPH patients with previously negative transrectal prostate biopsy. A prospective analysis of 51 patients with previously negative transrectal prostate biopsy who underwent surgical treatment using TmLRP-TT was performed from December 2011 to December 2013. Preoperative status, surgical details, and perioperative complications were recorded. The follow-up outcome was evaluated with subjective and objective tests at I and 6 months. TmLRP-TT was successfully completed in all patients. Mean prostate volume, operative duration, and catheterization time were 93.3 ± 37.9 ml, 69.5 ± 39.5 min, and 6.5 ± 1.3 days, respectively. The mean International Prostate Symptom Score, quality of life score, maximum urinary flow rate, and post-void residual urine volume changed notably at 6-month follow-up （22.5 ± 6.9 vs 6.1 ± 3.2, 4.8 ± 1.3 vs 1.1 ± 0.9, 7.3 ± 4.5 vs 18.9 ± 7.1 ml s^-1, and 148.7 ± 168.7 vs 28.4 ± 17.9 ml）. Two （3.9%） patients required blood transfusion perioperatively, while 3 （5.9%） patients experienced transient hematuria postoperatively, and 2 （3.9%） patients received 3 days recatheterization due to clot retention. TmLRP-TT is a safe and effective minimally invasive technique for patients with previously negative transrectal prostate biopsy during the 6-month follow-up. This promising technology may be a feasible surgical method for previously negative transrectal prostate biopsy in the future.

Low-intensity pulsed ultrasound for regenerating peripheral nerves:potential for penile nerve

Peripheral nerve damage,such as that found after surgery or trauma,is a substantial clinical challenge.Much research continues in attempts to improve outcomes after peripheral nerve damage and to promote nerve repair after injury.In recent years,low-intensity pulsed ultrasound(LIPUS)has been studied as a potential method of stimulating peripheral nerve regeneration.In this review,the physiology of peripheral nerve regeneration is reviewed,and the experiments employing LIPUS to improve peripheral nerve regeneration are discussed.Application of LIPUS following nerve surgery may promote nerve regeneration and improve functional outcomes through a variety of proposed mechanisms.These include an increase of neurotrophic factors,Schwann cell(SC)activation,cellular signaling activations,and induction of mitosis.We searched PubMed for articles related to these topics in both in vitro and in vivo animal research models.We found numerous studies,suggesting that LIPUS following nerve surgery promotes nerve regeneration and improves functional outcomes.Based on these findings,LIPUS could be a novel and valuable treatment for nerve injury-induced erectile dysfunction.

Prostatic anatomical parameters correlate with clinical characteristics suggestive of benign prostatic hyperplasia

We conducted the present study to assess the correlation of the prostatic anatomical parameters,especially the ratio of peripheral zone thickness and transitional zone thickness,with clinical and uroflowmetry characteristics suggestive of benign prostate hyperplasia(BPH).A total of 468 consecutive patients with a detailed medical history were identified.All patients were evaluated by scoring subjective symptoms with the International Prostate Symptom Score(IPSS)and quality of life(QoL).The prostatic anatomical parameters were measured using transrectal ultrasonography,and postvoid residual urine and maximum flow rate(Q_(max))values were also determined.Pearsonfs correlation analysis revealed that both total prostate volume(TPV;r=0.160,P<0.001)and transitional zone volume(TZV;r=0.104,P=0.016)increased with patients7 age;however,no correlations were observed of TPV,TZV,transitional zone index(TZI),and transitional zone thickness(TZT)with IPSS or QoL(all P>0.05).Peripheral to transitional zone index(PTI)was found negatively correlated with total IPSS(r=-0.113,P=0.024),storage IPSS(r=-0.103,P=0.041),and voiding IPSS(r=-0.123,P-0.014).As regards the uroflowmetry characteristics,PTI(r=0.157,P=0.007)was indicated to be positively correlated with Q_(max)and negatively correlated with TZI(r=-0.119,P=0.042)and TZT(r=-0.118,P=0.045),but not correlated with TPV,TZV,or peripheral zone thickness(PZT)(all P>0.05).Postvoid residual urine(PVR)had not correlated with all the prostatic anatomical variables(all P>0.05).This is the first study that formally proposed the concept of PTI,which is an easy-to-measure prostate anatomical parameter which significantly correlates with total IPSS,storage IPSS,voiding IPSS,and Q_(max),suggesting that PTI would be useful in evaluating and managing men with lower urinary tract symptoms(LUTS)/BPH.However,well-designed studies are mandatory to verify the clinical utility of PTI.

Low serum testosterone predicts upgrading and upstaging of prostate cancer after radical prostatectomy

Often, pathological Gleason Score （GS） and stage of prostate cancer （PCa） were inconsistent with biopsy GS and clinical stage.However, there were no widely accepted methods predicting upgrading and upstaging PCa. In our study, we investigated the association between serum testosterone and upgrading or upstaging of PCa after radical prostatectomy （RP）. We enrolled 167 patients with PCa with biopsy GS 〈6, clinical stage ≤T2c, and prostate-specific antigen （PSA） 〈10 ng ml-1 from April 2009 to April 2015. Data including age, body mass index, preoperative PSA level, comorbidity, clinical presentation, and preoperative serum total testosterone level were collected. Upgrading occurred in 62 （37.1%） patients, and upstaging occurred in 73 （43.7%） patients. Preoperative testosterone was lower in the upgrading than nonupgrading group （3.72 vs 4.56, P 〈 0.01）. Patients in the upstaging groUp had lower preoperative testosterone than those in the nonupstaging group （3.84 vs 4.57, P = 0.01）. In multivariate logistic regression analysis, as both continuous and categorical variables, low serum testosterone was confirmed to be an independent predictor of pathological upgrading （P = 0.01 and P = 0.01） and upstaging （P = 0.01 and P = 0.02） after RR We suggest that low serum testosterone （〈3 ng ml-1） is associated with a high rate of upgrading and upstaging after RP. It is better for surgeons to ensure close monitoring of PSA levels and imaging examination when selecting non-RP treatment, to be cautious in proceeding with nerve-sparing surgery, and to be enthusiastic in performing extended lymph node dissection when selecting RP treatment for patients with low serum testosterone.

A novel approach:successful management of vasectomy reversal with a three-dimensional digital image microscope system

Dear Editor,Microsurgical vasovasostomy,most commonly performed for vasectomy reversal,remains the most successful procedure for restoring patency to the vas deferens with the return of sperm to the ejaculate.Although the excellent results depend on the surgeons skill and technique,optimal vision and ergonomics are also crucial factors contributing to the achievement of good results during male infertility microsurgery.

Low-intensity pulsed ultrasound stimulates proliferation of stem/progenitor cells: what we need to know to translate basic science research into clinical applications

Low-intensity pulsed ultrasound (LIPUS) is a promising therapy that has been increasingly explored in basic research and clinical applications. LIPUS is an appealing therapeutic option as it is a noninvasive treatment that has many advantages, including no risk of infection or tissue damage and no known adverse reactions. LIPUS has been shown to have many benefits including promotion of tissue healing, angiogenesis, and tissue regeneration;inhibition of inflammation and pain relief;and stimulation of cell proliferation and differentiation. The biophysical mechanisms of LIPUS remain unclear and the studies are ongoing. In recent years, more and more research has focused on the relationship between LIPUS and stem/progenitor cells. A comprehensive search of the PubMed and Embase databases to July 2020 was performed. LIPUS has many effects on stem cells. Studies show that LIPUS can stimulate stem cells in vitro;promote stem cell proliferation, differentiation, and migration;maintain stem cell activity;alleviate the problems of insufficient seed cell source, differentiation, and maturation;and circumvent the low efficiency of stem cell transplantation. The mechanisms involved in the effects of LIPUS are not fully understood, but the effects demonstrated in studies thus far have been favorable. Much additional research is needed before LIPUS can progress from basic science research to large-scale clinical dissemination and application.