Vesico-obturator venous plexus - a rare termination of obturator vein.

Obturator vein usually terminates into the internal iliac vein. Its variations are the cause major bleeding problems in pelvic surgeries. We observed a rare variation in the termination of the right obturator vein. There was a duplication of right obturator vein. Both obturator veins entered the pelvic cavity through the obturator foramen and joined with two vesical veins to form a vesico-obturator plexus. This plexus surrounded the internal iliac artery and terminated into the internal iliac vein. Awareness of this rare variation could be of importance to anatomists, radiologists, gynaecologists, urologists, and orthopaedic surgeons. The plexus might lead to hazardous bleeding in pelvic lymph node clearance procedures, hernia surgeries, gynaecological and orthopaedic procedures in this region. The pelvic fractures too can provoke dramatic retroperitoneal hematomas related to these veins injuries.

Autologous Endothelial Progenitor Cells and Bioactive Factors Improve Bladder Regeneration.

Insufficient vascularization is still a challenge that impedes bladder tissue engineering and results in unsatisfied smooth muscle regeneration. Since bladder regeneration is a complex articulated process, the aim of this study is to investigate whether combining multiple pathways by exploiting a combination of biomaterials, cells, and bioactive factors, contributes to the improvements of smooth muscle regeneration and vascularization in tissue-engineered bladder. Autologous endothelial progenitor cells (EPCs) and bladder smooth muscle cells (BSMCs) are cultured and incorporated into our previously prepared porcine bladder acellular matrix (BAM) for bladder augmentation in rabbits. Simultaneously, exogenous vascular endothelial growth factor (VEGF) and platelet-derived growth factor BB (PDGF-BB) mixed with Matrigel were injected around the implanted cells-BAM complex. In the results, compared with control rabbits received bladder augmentation with porcine BAM seeded with BSMCs, the experimental animals showed significantly improved smooth muscle regeneration and vascularization, along with more excellent functional recovery of tissue-engineered bladder, due to the additional combination of autologous EPCs and bioactive factors, including VEGF and PDGF-BB. Furthermore, cell tracking suggested that the seeded EPCs could be directly involved in neovascularization. Therefore, it may be an effective method to combine multiple pathways for tissue-engineering urinary bladder.

Improved bladder function in radical hysterectomy without worsening oncologic outcome: resection of the posterior layer of the vesicouterine ligament with the procedure limited to the vesical veins.

OBJECTIVE: The classic Okabayashi nerve-sparing radical hysterectomy involves complete resection of the posterior leaf of the vesicouterine ligament, whereas in the simplified nerve-sparing radical hysterectomy, only the vesical veins and some connective tissue of the posterior layer of the vesicouterine ligament are resected. This study aimed to compare bladder function and cervical carcinoma relapse-free survival between these two techniques. METHODS: We conducted a retrospective, historical control study. All female patients aged >20 years who were diagnosed with cervical cancer stage IB1-IIB and underwent radical hysterectomy with pelvic lymphadenectomy between 2009 and 2022 were enrolled. Patients who had a history of other cancers and those who were treated with non-surgical approaches or non-radical hysterectomy were excluded. The primary outcome was relapse-free survival during the follow-up period. RESULTS: A total of 114 patients who underwent curative-intent radical hysterectomy were included in this study. The median follow-up duration was 60 months. No significant difference was observed in relapse-free survival between the two surgical procedures. The simplified nerve-sparing radical hysterectomy was superior in terms of both motor and sensory bladder function outcomes. CONCLUSION: Resection of the posterior layer of the vesicouterine ligament, with the procedure limited to the vesical veins, is an effective and safe method for radical hysterectomy. It may be more useful for preserving the bladder function, without leading to unfavorable oncologic outcomes.

Involvement of Mast-Cell-Tryptase- and Protease-Activated Receptor 2-Mediated Signaling and Urothelial Barrier Dysfunction with Reduced Uroplakin II Expression in Bladder Hyperactivity Induced by Chronic Bladder Ischemia in the Rat.

We aimed to investigate the relationship between mast cell (MC) infiltration into the bladder with urothelial barrier dysfunction and bladder hyperactivity in a chronic bladder ischemia (CBI) rat model. We compared CBI rats (CBI group; n = 10) with normal rats (control group; n = 10). We measured the expression of mast cell tryptase (MCT) and protease-activated receptor 2 (PAR2), which are correlated with C fiber activation via MCT, and Uroplakins (UP Ia, Ib, II and III), which are critical to urothelial barrier function, via Western blotting. The effects of FSLLRY-NH2, a PAR2 antagonist, administered intravenously, on the bladder function of CBI rats were evaluated with a cystometrogram. In the CBI group, the MC number in the bladder was significantly greater (p = 0.03), and the expression of MCT (p = 0.02) and PAR2 (p = 0.02) was significantly increased compared to that of the control group. The 10 µg/kg FSLLRY-NH2 injection significantly increased the micturition interval of CBI rats (p = 0.03). The percentage of UP-II-positive cells on the urothelium with immunohistochemical staining was significantly lower in the CBI group than in the control group (p < 0.01). Chronic ischemia induces urothelial barrier dysfunction via impairing UP II, consequently inducing MC infiltration into the bladder wall and increased PAR2 expression. PAR2 activation by MCT may contribute to bladder hyperactivity.

Posttraumatic hemorrhagic bladder rupture managed with transurethral foley catheter placement and bilateral transcatheter vesical artery embolization.

BACKGROUND: Outcome of minimally invasive treatment of posttraumatic, hemorrhagic bladder rupture is unknown. METHODS: A 41-year-old male presented at the emergency department with pelvic and scrotal pain and macroscopic hematuria after a motor vehicle accident. Contrast-enhanced computed tomography revealed an open book fracture and an arterial phase contrast media extravasation posterior to the symphysis pubis and anterior to the urethra-vesical junction. RESULTS: The open book fracture was treated with an external fixation and the persistent bleeding was managed with insertion of a Foley catheter and bilateral embolization of the vesical arteries. CONCLUSION: Minimally invasive treatment, including vesical artery embolization and placement of a Foley catheter can be effective in the treatment of posttraumatic, hemorrhagic bladder rupture.

Bladder augmentation from an insider's perspective: a review of the literature on microcirculatory studies.

Augmentation cystoplasty is an exemplary multiorgan intervention in urology which is particularly associated with microvascular damage. Our aim was to review the available intravital imaging techniques and data obtained from clinical and experimental microcirculatory studies involving the most important donor organs applied in bladder augmentation. Although numerous direct or indirect methods are available to assess the condition of microvessels the implementation of microcirculatory diagnostic methods in humans is still challenging and the assessment of organ microcirculation in the operating theatre has limitations. Nevertheless, preclinical studies generally report good internal validity and although prospective human protocols with reduced variability are needed, a possible positive impact of microcirculatory diagnostics on the clinical outcomes of urologic surgery can be anticipated.

Impairment of AMPK-α2 augments detrusor contractions in bladder ischemia.

PURPOSE: Ischemia disrupts cellular energy homeostasis. Adenosine monophosphate-activated protein kinase alpha-2 (AMPK-α2) is a subunit of AMPK that senses cellular energy deprivation and signals metabolic stress. Our goal was to examine the expression levels and functional role of AMPK-α2 in bladder ischemia. MATERIALS AND METHODS: Iliac artery atherosclerosis and bladder ischemia were engendered in apolipoprotein E knockout rats by partial arterial endothelial denudation using a balloon catheter. After eight weeks, total and phosphorylated AMPK-α2 expression was analyzed by western blotting. Structural integrity of AMPK-α2 protein was assessed by Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS). Functional role of AMPK-α2 was examined by treating animals with the AMPK activator 5-aminoimidazole-4-carboxamide-1-beta-D ribofuranoside (AICAR). Tissue contractility was measured in the organ bath and bladder nerve density was examined by immunostaining. RESULTS: Total AMPK-α2 expression increased in bladder ischemia, while phosphorylated AMPK-α2 was significantly downregulated. LC-MS/MS suggested post-translational modification of AMPK-α2 functional domains including phosphorylation sites, suggesting accumulation of catalytically inactive AMPK-α2 in bladder ischemia. Treatment of rats with AICAR diminished the force of overactive detrusor contractions and increased bladder capacity but did not have a significant effect on the frequency of bladder contractions. AICAR diminished contractile reactivity of ischemic tissues in the organ bath and prevented loss of nerve fibers in bladder ischemia. CONCLUSIONS: Ischemia induces post-translational modification of AMPK-α2 protein. Impairment of AMPK-α2 may contribute to overactive detrusor contractions and loss of nerve fibers in bladder ischemia. AMPK activators may have therapeutic potential against detrusor overactivity and neurodegeneration in bladder conditions involving ischemia.

Dynamic persistence of UPEC intracellular bacterial communities in a human bladder-chip model of urinary tract infection.

Uropathogenic Escherichia coli (UPEC) proliferate within superficial bladder umbrella cells to form intracellular bacterial communities (IBCs) during early stages of urinary tract infections. However, the dynamic responses of IBCs to host stresses and antibiotic therapy are difficult to assess in situ. We develop a human bladder-chip model wherein umbrella cells and bladder microvascular endothelial cells are co-cultured under flow in urine and nutritive media respectively, and bladder filling and voiding mimicked mechanically by application and release of linear strain. Using time-lapse microscopy, we show that rapid recruitment of neutrophils from the vascular channel to sites of infection leads to swarm and neutrophil extracellular trap formation but does not prevent IBC formation. Subsequently, we tracked bacterial growth dynamics in individual IBCs through two cycles of antibiotic administration interspersed with recovery periods which revealed that the elimination of bacteria within IBCs by the antibiotic was delayed, and in some instances, did not occur at all. During the recovery period, rapid proliferation in a significant fraction of IBCs reseeded new foci of infection through bacterial shedding and host cell exfoliation. These insights reinforce a dynamic role for IBCs as harbors of bacterial persistence, with significant consequences for non-compliance with antibiotic regimens.

Urinary tract infections are one of the most common reasons people need antibiotics. These bacterial infections are typically caused by uropathogenic Escherichia coli (also known as UPEC), which either float freely in the urine and wash away when the bladder empties, or form communities inside cells that the bladder struggles to clear. It is possible that the bacteria living within cells are also more protected from the immune system and antibiotics. But this is hard to study in animal models. To overcome this, Sharma et al. built a 'bladder-chip' which mimics the interface between the blood vessels and the tissue layers of the human bladder. Similar chip devices have also been made for other organs. However, until now, no such model had been developed for the bladder. On the chip created by Sharma et al. is a layer of bladder cells which sit at the bottom of a channel filled with diluted human urine. These cells were infected with UPEC, and then imaged over time to see how the bacteria moved, interacted with the bladder cells, and aggregated together. Immune cells from human blood were then added to a vascular channel underneath the bladder tissue, which is coated with endothelial cells that normally line blood vessels. The immune cells rapidly crossed the endothelial barrier and entered the bladder tissue, and swarmed around sites of infection. In some instances, they released the contents of their cells to form net-like traps to catch the bacteria. But these traps failed to remove the bacteria living inside bladder cells. Antibiotics were then added to the urine flowing over the bladder cells as well as the vascular channel, similar to how drugs would be delivered in live human tissue. Sharma et al. discovered that the antibiotics killed bacteria residing in bladder cells slower than bacteria floating freely in the urine. Furthermore, they found that bacteria living in tightly packed communities within bladder cells were more likely to survive treatment and go on to re-infect other parts of the tissue. Antibiotic resistance is a pressing global challenge, and recurrent urinary tract infections are a significant contributor. The bladder-chip presented here could further our understanding of how these bacterial infections develop in vivo and how good antibiotics are at removing them. This could help researchers identify the best dosing and treatment strategies, as well as provide a platform for rapidly testing new antibiotic drugs and other therapies.

Post-Translational Modification Networks of Contractile and Cellular Stress Response Proteins in Bladder Ischemia.

Molecular mechanisms underlying bladder dysfunction in ischemia, particularly at the protein and protein modification levels and downstream pathways, remain largely unknown. Here we describe a comparison of protein sequence variations in the ischemic and normal bladder tissues by measuring the mass differences of the coding amino acids and actual residues crossing the proteome. A large number of nonzero delta masses (11,056) were detected, spanning over 1295 protein residues. Clustering analysis identified 12 delta mass clusters that were significantly dysregulated, involving 30 upregulated (R2 > 0.5, ratio > 2, p < 0.05) and 33 downregulated (R2 > 0.5, ratio < -2, p < 0.05) proteins in bladder ischemia. These protein residues had different mass weights from those of the standard coding amino acids, suggesting the formation of non-coded amino acid (ncAA) residues in bladder ischemia. Pathway, gene ontology, and protein-protein interaction network analyses of these ischemia-associated delta-mass containing proteins indicated that ischemia provoked several amino acid variations, potentially post-translational modifications, in the contractile proteins and stress response molecules in the bladder. Accumulation of ncAAs may be a novel biomarker of smooth muscle dysfunction, with diagnostic potential for bladder dysfunction. Our data suggest that systematic assessment of global protein modifications may be crucial to the characterization of ischemic conditions in general and the pathomechanism of bladder dysfunction in ischemia.

Fetal Urinoma Due to Circulatory Disorders in an Umbilical Artery: Case Report.

Fetal urinoma is defined as an encapsulated accumulation of extravasated urine within the perirenal space or retroperitoneum. It is an uncommon finding in prenatal practice, and the vast majority of known cases are strongly associated with the existence of a urinary obstruction, such as posterior urethral valves, ureteropelvic junction obstruction, or ureterocele. We report a unique case of prenatally detected fetal bladder urinoma that occurred in the absence of an apparent obstructive uropathy, but was associated with extensive ischemic necrosis and calcifications of adjacent bladder wall, coexistent with signs of vascular supply decompensation.

Feasibility Study of Vascularized Composite Urinary Bladder Allograft Transplantation in a Cadaver Model.

PURPOSE: The purpose of this study was to establish the feasibility of performing a urinary bladder vascularized composite allograft transplantation for either bladder augmentation or neobladder creation. MATERIALS AND METHODS: Six adult cadavers were studied. Cadavers were excluded for any previous pelvic surgery, radiation, vascular surgery or history of pelvic malignancy. An intravascular colored silicone and barium mixture was injected and both computerized tomography scans and gross dissections were performed. Contrast enhanced computerized tomography imaging was used to delineate urinary bladder vascular anatomy variability. Bladders were explanted en bloc from 2 cadavers with bilateral vascular pedicles based on the external iliac vessels and "transplanted" to replicate a bladder transplant. RESULTS: Contrast enhanced 3-D-computerized tomography reconstructions and cadaver dissections revealed distal vascular variability with proximal blood supply based primarily on the internal iliac artery. Urinary bladder vascularized composite allograft transplantation was successfully performed during 2 mock transplants with the vascular anastomosis done to the recipient external iliac artery and vein. CONCLUSIONS: Urinary bladder vascularized composite allograft transplantation is technically and anatomically feasible. This procedure may obviate the use of intestinal segments for bladder reconstruction in select patients. A phase 1 clinical trial is in progress.

Superselective Vesical Artery Embolization for Intractable Hemorrhagic Cystitis Following Hematopoietic Stem Cell Transplantation: A Single-Center Retrospective Study in 26 Patients.

PURPOSE: To evaluate the safety and efficacy of superselective vesical artery embolization (SVAE) in the treatment of intractable hemorrhagic cystitis (HC) following hematopoietic stem cell transplantation (HSCT). METHODS: From January 2010 to December 2018, 26 patients with hematologic malignancy who underwent SVAE for treatment of intractable HC following HSCT were retrospectively reviewed. SVAE was performed with 300-500 µm gelatin-sponge particles initially. Technical success was defined as achieving bilateral SVAE for all the prominent vesical arteries. Therapeutic efficacy was defined as: Complete response (CR): macroscopic hematuria completely disappeared on more than 2 consecutive days after SVAE; Partial response (PR): macroscopic hematuria reduced after SVAE or briefly disappeared after SVAE but reappeared soon within 2 days; No response: no response to SVAE or hematuria aggravated after SVAE; Recurrence: macroscopic hematuria relapsed on follow-up after achieving an initial CR. Adverse events were also registered. RESULTS: There was a mean follow-up of 11.4 months (range, 0.5-83.7). The mean interval for the onset of HC after HSCT was 39.7 ± 19.0 days, and mean duration of hematuria before embolization was 14.9 ± 15.7 days. SVAE was technically successful in all patients. After embolization, macroscopic hematuria regressed within 48 h for all patients. The mean urine erythrocyte counts dropped from 14,213.2 ± 20,999.0/uL before SVAE to 6072.9 ± 12,720.7/uL on 3d after SVAE (P = 0.002) and 3720.2 ± 8988.9/uL on 7 d after SVAE (P = 0.001), respectively. Hematuria completely disappeared prior to discharge in 23 (88.5%) patients (including 20 with one embolization and 3 with 2 embolizations) and remainder 3 patients had PR. No major procedure-related complications were noted, except for post-embolization syndrome in 8 patients, which resolved with symptomatic treatment. On follow-up monthly, hematuria recurrence was seen in 4/23 patients (17.4%) and was managed conservatively in 2 patients and with repeat embolization in the remainder 2 patients. CONCLUSION: For fragile patients with hematologic malignancy, SVAE is safe and effective to treat HC following HSCT, even though repeat embolization may be required to achieve a sustained complete remission of the hematuria.

Hypothermia induces opposite response in vascular and non-vascular smooth muscles.

BACKGROUND AND AIM: The mechanism of cooling-induced response of smooth muscles remains little understood despite the increasing importance given to it in recent years. The aim of this study was to examine the possibility of releasing a relaxant or a contractile substance during cooling from vascular and non-vascular smooth muscles. METHODS: Assessing the effect of cooling for two different smooth muscles together, vascular (aorta or carotid) which induced relaxation, and non-vascular (jejunum or bladder) which induced contraction. Hanging a pair of smooth muscle strips from different body organs in the same organ bath filled with Krebs solution, each strip was connected to its own transducer and recorder and stepwise cooling was applied. Recordings of isometric tension using organ-bath techniques. RESULTS: Step-wise cooling (37 °C-4 °C) of aorta and carotid smooth muscle preparations induced reproducible graded relaxation while jejunum and bladder preparations induced reproducible graded tonic contractions, inversely proportional to temperature. The responses of all the smooth muscle preparations were the same magnitude either alone or as a pair in the organ bath. Cooling abolished rhythmic smooth muscle activity of jejunum and bladder. Cooling-induced contraction was reduced by incubation in Ca2+-free solution. The effect of cooling either relaxation or contraction was not enhanced or attenuated by the presence of the two different smooth muscles with opposite response in the same organ bath, proving the absence of a relaxant or a contractile substance released during cooling. CONCLUSIONS: Cooling of aorta and carotid artery induced relaxation while jejunum and bladder induced contraction. The response to cooling is inversely proportional to the temperature. There was neither a relaxant nor a contractile substance released from vascular or non-vascular smooth muscles during cooling. Our study suggested that the effect of cooling is through a thermal receptor with two subtype one in the vascular smooth muscle (deep blood vessels) which induces relaxation, and the second in non-vascular smooth muscles (non-vascular organs) that induces contraction and the responses depend on extracellular calcium.

Superselective vesical artery embolization for intractable bladder hemorrhage related to pelvic malignancy.

BACKGROUND: Intractable bladder hemorrhage from pelvic malignancy can be potentially life-threatening and its management can be a challenging clinical problem. PURPOSE: To evaluate safety, efficacy, and clinical outcome of superselective vesical artery embolization for the control of intractable bladder hemorrhage from pelvic malignancy. MATERIAL AND METHODS: Between January 2010 and September 2018, 20 patients underwent superselective vesical artery embolization for intractable hematuria secondary to pelvic malignancy arising from or invading the bladder. Treatment details and clinical outcomes were obtained. RESULTS: There were 12 men and 8 women (mean age = 77 years). Bilateral embolization was performed in 10 patients and unilateral approach in 10 patients. Two patients died within four days after embolization due to underlying heart failure and systemic metastasis, respectively. The remaining 18 patients had a follow-up of >30 days. Bleeding was controlled after the first embolization in 17/18 patients and after a repeat embolization in the remaining one patient. The mean follow-up period of 18 patients was 10.6 months (range = 1-77 months). Late recurrent hemorrhage (≥ 30 days after embolization) was reported in 6 (33.3%) patients. Five of these six patients underwent repeat embolization. There were no major complications related to embolization. CONCLUSION: Palliative superselective vesical artery embolization is a feasible, effective, and safe procedure to control intractable hematuria in patients with pelvic malignancy.

Microvascular anatomy of the urinary bladder in the adult African clawed toad, Xenopus laevis: A scanning electron microscope study of vascular casts.

We studied urinary bladders of adult male and female Xenopus laevis using light microscopy of stained tissue sections and scanning electron microscopy (SEM) of vascular corrosion casts (VCCs). Results showed that bilaterally a vesical artery branched off the femoral artery. At the dorso-lateral serosal surface of the body of the bladder each artery splitted within a short distance into up to five smaller arteries that supplied body and neck regions. Arteries gave off short and long terminal arterioles, which fed the mucosal capillary meshwork. Long terminal arterioles followed dimensional changes of the bladder, while short ones anchored the capillary network to the arterial system. Capillary mesh sizes and shapes varied according to the filling state of the urinary bladder. In the highly to moderately distended (filled) bladder, capillaries were rather straight or undulated only slightly, in the contracted (emptied) bladder they undulated strongly and lay side by side. Postcapillary venules formed by two equally sized capillaries or from capillaries, which serially drained into a small postcapillary venule. Vesical venules formed a large dorsal vesical and a varying number of smaller lateral and ventral vesical veins. The dorsal vesical vein drained either directly or via the posterior hemorrhoidal vein into the common pelvic vein. Lateral and ventral vesical veins also drained into the latter. The vascular patterns found were discussed in respect to the bladder spatial movements during distention (filling) and relaxation (emptying). Furthermore, it was hypothesized that an extensively filled bladder could compress the overlaying abdominal vein forcing part of the blood otherwise drained towards the liver to be detoured via the renal portal veins to the kidneys.

Sclerotherapy treatment of a large venous malformation invading the bladder wall related to Klippel-Trenaunay syndrome.

We report the case of a 35-year-old woman who presented with recurrent macroscopic haematuria and known diagnosis of Klippel-Trenaunay syndrome. Imaging and cystoscopy identified an extensive venous malformation involving a large area of the bladder wall. Holmium laser therapy was ineffective at obtaining symptom control. Following a multidisciplinary team meeting, transvenous sclerotherapy with sodium tetradecyl sulphate was performed under image guidance. A reduction in venous density was observed on cystoscopy and the patient has had complete resolution of symptoms within 6 weeks and continued to be asymptomatic up to 24-month follow-up. We propose that transvenous sclerotherapy is considered first-line treatment in this clinical setting.

Tetrahydrobiopterin prevents chronic ischemia-related lower urinary tract dysfunction through the maintenance of nitric oxide bioavailability.

This study aimed to investigate the influence of chronic ischemia on nitric oxide biosynthesis in the bladder and the effect of administering tetrahydrobiopterin (BH4), a cofactor for endothelial nitric oxide synthase (eNOS), on chronic ischemia-related lower urinary tract dysfunction (LUTD). This study divided male Sprague-Dawley rats into Control, chronic bladder ischemia (CBI) and CBI with oral BH4 supplementation (CBI/BH4) groups. In the CBI group, bladder capacity and bladder muscle strip contractility were significantly lower, and arterial wall was significantly thicker than in Controls. Significant improvements were seen in bladder capacity, muscle strip contractility and arterial wall thickening in the CBI/BH4 group as compared with the CBI group. Western blot analysis of bladder showed expressions of eNOS (p = 0.043), HIF-1α (p < 0.01) and dihydrofolate reductase (DHFR) (p < 0.01), which could regenerate BH4, were significantly higher in the CBI group than in Controls. In the CBI/BH4 group, HIF-1α (p = 0.012) and DHFR expressions (p = 0.018) were significantly decreased compared with the CBI group. Our results suggest that chronic ischemia increases eNOS and DHFR in the bladder to prevent atherosclerosis progression. However, DHFR could not synthesize sufficient BH4 relative to the increased eNOS, resulting in LUTD. BH4 supplementation protects lower urinary tract function by promoting eNOS activity.

Bladder reconstruction using autologous smooth muscle cell sheets grafted on a pre-vascularized capsule.

Rationale: Construction of functional vascularized three-dimensional tissues has been a longstanding objective in the field of tissue engineering. The efficacy of using a tissue expander capsule as an induced vascular bed to prefabricate functional vascularized smooth muscle tissue flaps for bladder reconstruction in a rabbit model was tested. Methods: Skin tissue expanders were inserted into the groin to induce vascularized capsule pouch formation. Smooth muscle cells and endothelial progenitor cells were harvested and cocultured to form pre-vascularized smooth muscle cell sheet. Then repeated transplantation of triple-layer cell sheet grafts onto the vascularized capsular tissue was performed at 2-day intervals to prefabricate functional vascularized smooth muscle tissue flaps. Bladder muscular wall defects were created and repaired by six-layer cell sheet graft (sheet only), capsule flap (capsule only) and vascularized capsule prelaminated with smooth muscle cell sheet (sheet plus capsule). The animals were followed for 3 months after implantation and their bladders were explanted serially. Results: Bladder capacity and compliance were maintained in sheet plus capsule group throughout the 3 months. Tissue bath stimulation demonstrated that contractile responses to carbachol and KCl among the three groups revealed a significant difference (p < 0.05). Histologically, inflammation was evident in the capsule only group at 1 month and fibrosis was observed in sheet only group at 3 months. The vessel density in capsule only and sheet plus capsule group were significantly higher than in the sheet only group at each time point (p < 0.05). Comparison of the smooth muscle content among the three groups revealed a significant difference (p < 0.05). Conclusion: These results proved that the capsule may serve as an induced vascular bed for vascularized smooth muscle tissue flap prefabrication. The prefabricated functional vascularized smooth muscle tissue flap has the potential for reliable bladder reconstruction and may create new opportunities for vascularization in 3-D tissue engineering.

Single-cell analysis uncovers fibroblast heterogeneity and criteria for fibroblast and mural cell identification and discrimination.

Many important cell types in adult vertebrates have a mesenchymal origin, including fibroblasts and vascular mural cells. Although their biological importance is undisputed, the level of mesenchymal cell heterogeneity within and between organs, while appreciated, has not been analyzed in detail. Here, we compare single-cell transcriptional profiles of fibroblasts and vascular mural cells across four murine muscular organs: heart, skeletal muscle, intestine and bladder. We reveal gene expression signatures that demarcate fibroblasts from mural cells and provide molecular signatures for cell subtype identification. We observe striking inter- and intra-organ heterogeneity amongst the fibroblasts, primarily reflecting differences in the expression of extracellular matrix components. Fibroblast subtypes localize to discrete anatomical positions offering novel predictions about physiological function(s) and regulatory signaling circuits. Our data shed new light on the diversity of poorly defined classes of cells and provide a foundation for improved understanding of their roles in physiological and pathological processes.

Comparison of vascularization and overall perfusion of the bladder wall between women with and without overactive bladder syndrome.

The pathophysiology of female overactive bleeder syndrome (OAB) remains undetermined. Our aim is to elucidate the role of vacularization and overall perfusion of the bladder wall in women with OAB. Between 2010 and 2016, women with OAB and the asymptomatic controls were enrolled. Women with OAB were treated with tolterodine. Women with OAB (n = 40) had higher vascularization index (0.40 ± 0.57 versus 0.17 ± 0.22, p = 0.003), vascularization-flow index (0.15 ± 0.28 versus 0.05 ± 0.08, p = 0.003) and thicker trigone (0.56 ± 0.13 cm versus 0.47 ± 0.11 cm, p = 0.004), compared with the controls (n = 34). The following optimum cut-off values to predict OAB were determined: (1) vascularization index (%) ≥ 0.16, (2) vascularization-flow index ≥ 0.032, and (3) trigone bladder wall thickness ≥ 0.47 cm with an area under the curve of 0.71, 0.71 and 0.70, respectively. Correlation analysis showed that a significant correlation between urgency and vascularization index/vascularization-flow index (Spearman's rho = 0.34 and 0.35, respectively, all p < 0.01). However, after 12 weeks of tolterodine treatment, the vascularization index, flow index and vascularization-flow index did not differ between baseline and after treatment. In conclusion, women with OAB have higher vascularization and overall perfusion of the bladder wall, compared women without OAB. However, vascularization and overall perfusion did not change after antimuscarinic treatment.