Laparoscopic variability of the internal inguinal ring: review of anatomical variation in children with and without a patent processus vaginalis

PURPOSE: Diagnostic laparoscopy is routinely performed at our institution in children with a unilateral inguinal hernia to determine whether the contralateral processus vaginalis is patent. We reviewed the anatomical variability of the inguinal ring at laparoscopy in children with and without a hernia in various age groups. MATERIALS AND METHODS: Since 1992, we have performed diagnostic laparoscopy in more than 1,500 children with a known inguinal hernia. Intraoperative imaging was correlated with clinical and operative findings to characterize the anatomical variability of the internal ring. RESULTS: The internal ring had many variations. The photographs presented show evidence of the progression from the flat closed ring to the widely open sac. Clefts and veils of peritoneum sometimes made determining the exact anatomy difficult. Experience shows that the various anatomical variations are associated with different pathological conditions. CONCLUSIONS: Characterization of the anatomical variability of the internal ring is essential for determining the patency of the processus vaginalis at diagnostic laparoscopy in children with a known inguinal hernia. We classified these variations in accordance with clinical and surgical findings.     

Structural changes of smooth muscle in congenital ureteropelvic junction obstruction

Background/Purpose

Ureteropelvic junction (UPJ) obstruction is the most common cause of congenital hydronephrosis. Previous studies have reported that the excess amount of collagen restricting mobility and resiliency of the UPJ is the result of an impaired collagen production by anomalous smooth muscle cells (SMCs). Our purpose was to evaluate the role of SMC differentiation in the pathogenesis of UPJ obstruction.

Methods

Surgical specimens of UPJ from 21 patients (8 girls/13 boys) who were subjected to dismembered pyeloplasty were examined immunohistochemically using monoclonal antibodies against smooth muscle (SM) myosin heavy chain isoforms including SM1, SM2, and SMemb. The age ranged from 1 month to 13 years. Ureteropelvic walls taken from 14 forensic autopsy cases, with no urological abnormalities, served as age-matched control group.

Results

The immunohistochemical expression of SM1 and SM2 in UPJ obstruction was significantly increased when compared with controls (P < .05). In contrast, there was no statistical difference of expression of SMemb.

Conclusion

Our findings supported the hypothesis that the primary anomaly in UPJ obstruction may be attributed to a malfunction of SMCs in the ureter.     

Autonomic nervous system appears to play a role in obliteration of processus vaginalis

Background: Failed obliteration of processus vaginalis (PV) has recently been proposed to be due to persistence of the smooth muscle (SM), which is transiently present to generate the physical force to descend the testis. Sacs from hernia, hydrocele, or undescended testis reveal alterations in Ca²⁺ contents. Since Ca²⁺ signaling and some regulatory proteins are involved in programmed cell death (PCD), a flow cytometric evaluation was planned to evaluate the expression of inducers or inhibitors of PCD in sacs from different diagnostic sources. Methods: Sacs associated with male hernia (n=16), female hernia (n=11), undescended testis (n=9), and hydrocele (n=11) were evaluated for binding of annexin and expressions of Bcl-2, Bax, Fas, Fas-ligand (Fas-L), and Fas+Fas-L. The binding and expressions in cells that express -smooth muscle actin (-SMA) were also determined. Expressions according to the groups were compared through unpaired t-test, and P values less than 0.05 were considered to be significant. Results: Sacs associated with undescended testis that contain the least SM revealed the most annexin binding, and sacs associated with hernia that contain the most SM binded the least annexin. However, expressions of Bcl-2, Bax, Fas, Fas-L and Fas+Fas-L have not revealed a significant difference. On the other hand, Bax and Fas expressions of cells that express -SMA have been significantly higher in sacs associated with undescended testis. Conclusions: Since increase of Bax and Fas in cells that express -SMA are encountered in sacs with the least SM content, Bax and Fas appear to play roles in the amount of persisting SM. The necessities of initial depletion of Ca²⁺ stores through inositol 1,4,5-trisphosphate receptors and subsequent increase of Bax and Fas levels in the mitochondrial pathway of PCD, together with the role of the sympathetic system in maintenance of SM, suggest a determinative role of the autonomic nervous system for obliteration of PV.     

经脐两孔无瘢痕腹腔镜鞘状突口腹膜外缝扎术的临床研究

目的:探讨经脐两孔无瘢痕腹腔镜鞘状突口腹膜外缝扎术的可行性。方法:回顾分析为90例患儿行经脐两孔无瘢痕腹腔镜鞘状突口腹膜外缝扎术的临床资料。结果:90例手术均获成功,单侧单纯鞘状突口缝扎时间3~8m in,平均5m in。结论:经脐腹腔镜鞘状突口腹膜外缝扎术设计合理、简练、可行,需用器械简单,术后腹壁无可见瘢痕,值得推广。     

Small lungs and suspect smooth muscle: congenital diaphragmatic hernia and the smooth muscle hypothesis

Lung hypoplasia and congenital diaphragmatic hernia (CDH) represent an unsolved clinical and scientific problem. Early lung morphogenesis is coupled to development and function of pulmonary smooth muscle. Activity of the latter is abnormal from the earliest stages of hypoplastic lung development and before supervening CDH. A “smooth muscle hypothesis” is advanced to help explain embryonic lung malformations, fetal failure of lung growth, and postnatal susceptibility to barotrauma, airway hyperreactivity, and pulmonary hypertension in CDH. Exploring the interaction of smooth muscle function and airway pressures may help optimise tracheal occlusion and provide support for both an adequately powered trial of glucocorticoids and also for experimental “preventilation” strategies in fetal CDH.     

Adopt a wait-and-see attitude for patent processus vaginalis in neonates

Purpose: The purpose of this paper is to describe the ultrasonographic findings of the patent processus vaginalis (PPV) in neonates.Methods: The patency of the processus vaginalis was examined by ultrasonography in 117 neonates. The ultrasonographic findings, with increment and decrement of the intraabdominal pressure, were categorized into 6 types as follows: type I, the intraabdominal organ is observed; type II, cystic PPV; type III, the PPV is widened with abdominal pressure increment, the length is ≥20 mm; type IV, the PPV contains moving fluid without PPV widening; type V, the PPV is widened with abdominal pressure increment, the length is less than 20 mm; type VI, others. The authors we regarded types I to IV as PPV with inguinal hernia.Results: Twenty-two of 40 neonates with a birth weight under 2,500 g had PPV, including 8 with type I. Twenty of 37 premature neonates 22 to 37 gestational weeks had PPV, including 8 with type I. Eighty-one percent (13 of 16) of PPV in low-birth-weight neonates and 91% (10 of 11) in premature neonates closed spontaneously. The median ages at the time of spontaneous regression of PPV were 242 days in low birth weight neonates and 262 days in premature neonates.Conclusions: Most premature or low-birth-weight neonates with PPV regress spontaneously. The inguinal hernia in neonates (especially in premature or low-birth-weight neonates) should be observed until at least 9 months of age without attempting hernia repair.     

The low scrotal approach to the ectopic or ascended testicle: prevalence of a patent processus vaginalis

PURPOSE: The scrotal approach to undescended testis has been described using a high scrotal incision and including hernia repair. We describe an approach that uses a low scrotal incision with an inguinal incision if a patent processus is identified. We retrospectively reviewed the likelihood of a patent processus in children selected to undergo this technique. MATERIALS AND METHODS: A total of 56 consecutive patients determined by history and physical examination to have ectopic or ascended testes underwent orchiopexy using an initial scrotal approach for a total of 71 undescended testes. Inguinal surgery had previously been done in 5 testes, which were not included in patent processus analysis. Charts were reviewed for testicular position, need for inguinal incision and demographic data. RESULTS: Of the patients 16 (19 testes) were younger than 2 years, 19 (26 testes) were 2 to 6 years old and 17 (21 testes) were older than 6 years. In 20% of the patients an inguinal incision was made for a patent processus vaginalis. The incidence of a patent processus was 26% in those younger than 2 years, 15% in those 2 to 6 years old and 19% in those older than 6 years (p = 0.17). All patients had satisfactory scrotal placement with at least 1 followup examination. CONCLUSIONS: Children with ectopic or ascended testes on physical examination findings may be treated successfully via a low scrotal approach with only 20% requiring concomitant inguinal hernia repair through a standard inguinal incision. Overall 80% of the children avoided an inguinal incision. This technique has become our standard approach to these testes.     

Smooth muscle cell differentiation in the processus vaginalis of children with hernia or hydrocele

Purpose  

Incomplete obliteration of the processus vaginalis (PV) in children with inguinal hernia or hydrocele has recently been proposed to relate to smooth muscle cell (SMC) persistence. The aim of this study was to evaluate the diversity and differentiation of smooth muscle phenotypes in sacs associated with inguinal hernia and hydrocele through the expression of α-smooth muscle actin (SMA), h-caldesmon, desmin, and vimentin.     

The development and closure of the processus vaginalis

Summary It is now well known that the failure of the processus vaginalis (PV) to close off following descent of the testis not only accounts for nearly all inguinal hernias of childhood [Rothenberg et al, 1953], but also for other common congenital conditions of childhood such as scrotal hydroceles and encysted hydroceles of the cord. Despite the direct relationship of the PV to these conditions and its intimate association with the mechanism of testicular descent, surprisingly little is known about this important structure. It is not known, for instance, how the PV develops, what precise role it plays in testicular descent, what makes it close, or exactly when it closes. The purpose of this paper is to review the past and present literature on the PV, examining specifically its role in testicular descent, its postulated modes of development, and the mechanisms of its closure and disappearence following descent of the testis.     

Involvement of Rho-kinase in the contractile mechanism of human ureteral smooth muscle

AIM: Even though many agents have been implicated as modulators of ureteral contractile activity, the exact mechanisms that control human ureteral smooth muscle contractility have yet to be clearly defined. Recently, Rho-kinase has been reported to be involved in the contractile mechanism of smooth muscles in various organs. In the present study, we sought to investigate whether or not Rho-kinase is expressed in the human ureteral smooth muscle, and to study its role regarding human ureteral smooth muscle contractility. METHODS: Ureteral samples were obtained from human adult subjects undergoing radical nephrectomy. Immunohistochemistry and Western blotting were performed to determine the presence of Rho-kinase in human ureter. Functional studies were performed with human ureteral strips suspended in organ bath, and the effects of Y-27632, a specific inhibitor of Rho-kinase, on baseline tensions, spontaneous contractions, and electrical field stimulation (EFS)-induced contractions were analyzed. RESULTS: The results of immunohistochemistry and immunoblotting study indicated that Rho-kinase is present in human ureteral smooth muscle. In functional analysis, Y-27632 was shown to decrease the baseline tension. And, both spontaneous and EFS-induced contractile responses of human ureteral strips were attenuated by Y-27632 in dose-dependent manners. CONCLUSIONS: For the first time, the results of the present study indicate that Rho-kinase is present in human ureteral smooth muscle and may play an important role in the intricate mechanism of human ureteral contractility and tone.     

Preoperative sonographic evaluation is a useful method of detecting contralateral patent processus vaginalis in pediatric patients with unilateral inguinal hernia

Background/purpose

To analyze the value of ultrasound scan (US) in the preoperative identification of a contralateral patent processus vaginalis (CPPV), the authors investigated the presence of CPPV by US in children with clinically diagnosed unilateral inguinal hernias.

Methods

Three hundred forty-eight patients (168 boys and 180 girls) with unilateral inguinal hernia underwent US examination using a 7.5-MHz linear transducer. If a CPPV was visible as a hydrocele owing to the inflow of physiologic ascites into a processus vaginalis on straining, then US scanning was performed while the patient was at rest and while inducing straining by standing or crying. A groin with a hydrocele in the inguinal canal on straining was diagnosed as a CPPV and was explored bilaterally through surgery. The US findings were compared with surgical results.

Results

In 348 patients, 78 cases (22.4%) were diagnosed by US as patients with a CPPV; these patients underwent bilateral surgery. Seventy-four of 78 cases (94.9%) were confirmed surgically as patients with CPPV.

Conclusions

A CPPV was detected correctly by US in 74 of 348 patients (21.3%) with clinically diagnosed unilateral inguinal hernias. US is a noninvasive and accurate method for evaluating the presence of a CPPV.     

异丙酚对兔离体气管平滑肌舒张作用机制的研究

目的探讨异丙酚在正常和炎症状态下对气管平滑肌收缩作用的影响及其机制。方法8只健康新西兰大白兔,每次试验用气栓法处死1只,每只兔制备8个气管平滑肌条,依据悬挂气管平滑肌条的营养液中处理因素不同,采用随机数字表法将气管平滑肌条随机分为8组即（每组8个）：a组（0μmol/L）,b组（异丙酚300μmol／L）,c组（环糊精-β10mmol／L）,d组（环糊精-β10mmol／L＋异丙酚300μmol／L）,c组（0μmol／L）,f组（异丙酚300μmol／L）,g组（环糊精-β10mmol／L）,h组（环糊精-β10mmol／L＋异丙酚300μmol／L）。e,f,g,h4组气管平滑肌条浸于浓度为50μg／L肿瘤坏死因子-α溶液里,并通以95％O2和5％CO2在4℃恒温冰箱冷藏12h以供试验。用Medlab生物采集系统记录平滑肌条不同时间点张力值变化。免疫组化法测定小窝蛋白-1表达。结果与a组（1．28±0．12、1．25±0．13、1．23±0．16、1．22±0．19）比较,b组（0．86±0．13、0．61±0．11、0．51±0．17、0．51±0．18）、c组（1．18±0．15、1．08±0．13、0．98±0．15、0．89±0．16）、d组（0．98±0．12、0．84±0．14、0．80±0．14、0．78±0．17）T1。时间点张力值降低,差异有统计学意义（P〈0．05）;与b组比较c,d两组T1-4各时间点张力值高,差异有统计学意义（P〈0．05）;与e组（0．92±0．16、0．91±0．12、0．89±0．13、0．81±0．16）比较,f组（0.41±0．12、0．22±0．14、0．13±0．14、0．12±0．14）、g组（0．80±0．15、0．78±0．13、0．75±0．15、0．72±0．17）、h组（0．79±0．12、0．70±0．12、0．68±0．16、0．68±0．19）T1-4时间点张力值降低,差异有统计学意义（P〈0．05）;与f组比较g、h两组T1-4时间点张力值高,差异有统计学意义（P〈0．05）;8xe两组小窝蛋白-1为高表达;b、f两组小窝蛋白．1为低表达;c、d、g、h4组小窝蛋白-1为阴性。结论异丙酚直接舒张气管平滑肌的机制可能与其抑制小窝蛋白-1的表达有关。     

Laparoscopic repair on asymptomatic contralateral patent processus vaginalis in children with unilateral inguinal hernia: A centre experience and review of the literature

Purpose: We investigate the prevalence of contralateral patent processus vaginalis (CPPV) in children presenting with symptomatic unilateral inguinal hernia under diagnostic laparoscopy and its implication on contralateral surgery. Methods: Over a 24‐month period, 79 children (66 boys, 13 girls) aged 1 month to 8 years with symptomatic unilateral inguinal hernia underwent laparoscopic hernia repair. Twenty‐nine patients (36.7%) were under 24 months of age and 45 (57.0%) presented with right inguinal hernia. The contralateral internal inguinal ring was evaluated for CPPV. Bilateral repairs were carried out if CPPV was present. Results: The overall prevalence of asymptomatic CPPV was 39.2% in children who presented with unilateral inguinal hernia. The prevalence of asymptomatic CPPV was 48.3% for children aged under 24 months old and 26.0% in children above 24 months old (P = 0.044). CPPV was present in 52.9% of left‐side hernia under laparoscopy and in 28.9% of right‐side hernia (P = 0.030). Conclusion: The prevalence of asymptomatic CPPV under laparoscopy is nearly twice the reported incidence of symptomatic contralateral hernia development after conventional unilateral herniotomy. Further studies on the natural history of CPPV are necessary to determine the indications for repair of asymptomatic CPPV.     

Arresten对血管平滑肌细胞作用和机制的研究

目的探讨arresten蛋白对人血管平滑肌细胞的作用以及可能的相关调控机制。方法采用实时活细胞动态成像实验检测不同浓度arresten对血管平滑肌细胞增殖能力的影响;采用蛋白芯片检测在arresten作用下血管平滑肌细胞内差异性表达的相关细胞因子;采用实时荧光定量聚合酶链反应(RT-PCR)检测相关细胞因子的差异性表达。结果实时活细胞动态成像显示arresten能够抑制血管平滑肌细胞增殖水平;蛋白芯片实验显示arresten作用下血管平滑肌细胞内Angiogenin、Endoglin及TIMP-1具有差异性表达;RT-PCR结果验证了在arresten作用下血管平滑肌细胞内Angiogenin的差异性表达,Endoglin和TIMP-1表达差异不明显。结论arresten对血管平滑肌细胞增殖有抑制作用,其机制可能通过Angiogenin参与信号通路的调节来发挥作用。     

Effect and mechanism of chitosan inhibiting vascular smooth muscle cell hyperplasia of uremia patients

Objective To investigate the effect and mechanism of chitosan on vascular smooth muscle cell proliferation of uremia patients with arteriovenous fistula. Methods Primarily culturing the VSMCs of uremia patients with arteriovenous fistula and patients without uremia by explants adherent method, and taking the second generation. VSMCs from patients without uremia cultured with 20% FBS medium were non-uremia group, VSMCs of uremia patients cultured with 20% FBS medium were uremia group, VSMCs of uremia patients with 100 μg/ml chitosan were uremia+chitosan group. The expression of α-SMA was detected by immunohistochemistry. The changes of migration and invasion of VSMCs were detected by scratches and transwell migration assays. The mRNA expressions of TLR4 and PCNA were measured by real-time PCR. VSMCs of uremia patients with arteriovenous fistula were intervened with different doses of chitosan (0, 100 and 500 μg/ml), and the protein expressions of TLR4, MyD88 and NF-κB were detected by Western blotting. Results Compared with those in non-uremia group, in uremia group and uremia+chitosan group α-SMA was up-regulated, migration and invasion of VSMCs were enhanced, and mRNA expressions of TLR4 and PCNA were increased (all P＜0.05). Compared with those in uremia group, the level of α-SMA was significantly decreased, the ability of migration and invasion of VSMCs were decreased, and the mRNA expressions of TLR4 and PCNA were decreased (all P＜0.05). TLR4, MyD88 and NF-κB protein expressions were reduced in concentration-dependent manner by 100 and 500 μg/ml chitosan. Conclusions (1) In vitro, chitosan decreases the ability of migration and invasion of VSMCs of uremia patients with arteriovenous fistula. (2) Chitosan inhibits the proliferation of VSMCs, which may be relevant in the decreased expressions of TLR4, MyD88 and NF-κB.     

Patent processus vaginalis in adults who underwent robot‐assisted laparoscopic radical prostatectomy: Predictive signs of postoperative inguinal hernia in the internal inguinal floor

Objective: To evaluate the risk for postoperative inguinal hernia according to the presence of patent processus vaginalis in an adult population. Methods: Medical records of 205 patients who underwent robot‐assisted laparoscopic radical prostatectomy from May 2007 to November 2011 were reviewed. Age, prostate‐specific antigen, prostate volume, body mass index, operative time and history of previous abdominal surgery were evaluated. The existence of patent processus vaginalis was also evaluated for the development of postoperative inguinal hernia. Results: Postoperative inguinal hernia occurred in 20 out of 410 (4.9%) groins (17/205 patients; 8.3%), and patent processus vaginalis was observed in 49 out of 410 (11.9%) groins. In the normal groin group, inguinal hernia occurred in seven out of 361 (1.9%) groins. However, in the patent processus vaginalis group, it occurred in 13 out of 49 (26.5%) groins. On univariate analysis using Cox proportional hazards model, age, body mass index, history of previous abdominal surgery and patent processus vaginalis were significant risk factors. Among them, patent processus vaginalis significantly increased the risk of postoperative inguinal hernia in multivariate analysis (hazard ratio 22.37). In the patent processus vaginalis group, inguinal hernia developed at 12.9 ± 9.2 months after robot‐assisted laparoscopic radical prostatectomy and 15 ± 7.4 months in the normal groin group. Inguinal hernia‐free ratios were significantly lower in the patent processus vaginalis group than the normal groin group (P < 0.001). Conclusions: The existence of patent processus vaginalis represents an important risk factor for postoperative inguinal hernia in adults. Urologists should consider the possibility of postoperative inguinal hernia when patent processus vaginalis is observed during surgery.     

Human prostatic smooth muscle cells in culture: Estradiol enhances expression of smooth muscle cell-specific markers

Smooth muscle cells (SMCs) constitute a major cellular component of prostatic stroma. SMC tension plays an important role in urethral obstruction secondary to benign prostatic hyperplasia (BPH). We have developed an in vitro procedure for the propagation of human prostatic SMCs. Tissue specimens from patients undergoing radical prostatectomy or cystectomy were enzymatically disaggregated and cultured in MCDB-131 medium supplemented with horse serum, insulin, conditioned medium from the tumor cell line CRL-5813, and steroid hormones. The medium was assembled on the basis of the effects these supplements have on the growth of SMC cultures and on the expression of the two markers desmin and smooth muscle myosin. Addition of 0.1 μM of estradiol to the growth medium dramatically increased expression of these SMC-specific markers. Dihydrotestosterone (DHT) and hydrocortisone had a similar, albeit less pronounced effect. At three to five passages, about two thirds of the cells were immunohistologically positive for smooth muscle myosin or desmin. Almost all cells were positive for the myofibroblast marker smooth muscle α-actin throughout 10 passages and more. In SMC cultures, cells staining for smooth muscle myosin and desmin were found to seek direct contact to myofibroblasts. They grew in aggregates on a layer of myofibroblasts which adhered to the surface of the culture vessel. As revealed by transmission electron microscopy the cultured cells exhibited morphological features of myofibroblasts. Characteristics of smooth muscle cells, such as prominent bundles of microfilaments associated with dense bodies, basal laminae investing the cells, and numerous caveolae at the cell surfaces were regularly observed in cultures of low passages. After several passages, these features were markedly decreased and organelles of the biosynthetic system became more prominent. In summary, we present an in vitro model of prostatic SMCs and demonstrate that steroid hormones have characteristic effects on these cells. SMC cultures are expected to facilitate investigation of the functions and properties of human prostatic SMCs. Prostate 30:117–129, 1997. © 1997 Wiley-Liss, Inc.     

Old age does not affect shortening velocity or content of contractile and cytoskeletal proteins in the rat detrusor smooth muscle

The influence of old age on mechanical properties of the urinary bladder was investigated using smooth muscle strips from urinary bladders of control (14–16 weeks) and old-age (104 weeks) female Sprague-Dawley rats. Bladder weight of the aged rats had increased by about 30%. The maximal shortening velocity and stiffness in skinned activated urinary bladder fibers from old animals were unchanged compared to controls. The relative content of intermediate filament proteins to actin and the relative content of myosin to actin was unchanged. The concentration of myosin was unchanged (about 6.5 g/mg wet weight). The results suggest that old age is not associated with pronounced changes in the cellular contractile and cytoskeletal proteins or in the mechanical properties of the contractile machinery. The age-related changes in mechanical properties previously reported for intact smooth muscle from urinary bladder are most likely due to alterations in the activation systems.     

利多卡因对气管平滑肌舒张作用的研究

利多卡因是临床上常用的局部麻醉药和抗室性心律失常药物;除此之外,利多卡因还具有较强的扩张气道、抑制气道炎症、降低气道高反应性的作用。此方面的研究最早可追溯到上世纪60年代,利多卡因在围术期预防和处理支气管痉挛中所占的地位已得到充分肯定,现将近10余年来利多卡因对气道平滑肌影响的主要研究成果综述如下。