Robotic surgery for pelvic organ prolapse with complete bladder eversion

Introduction

Pelvic organ prolapse with complete bladder eversion is extremely rare.

Case presentation

An 82‐year‐old woman was diagnosed with uterine prolapse 3 years ago and underwent occasional urethral catheter placement for difficulty in micturition. She presented with vulvar bleeding and prolapsed uterus from the vagina. Pelvic examination revealed uterine prolapse and a 65 × 65‐mm red mass ventrally with urinary outflow. Contrast medium leakage from the vulvar mass and guidewire observed on antegrade pyeloureterography indicated pelvic organ prolapse with complete bladder eversion. Manual reduction of the everted bladder, robotic sacrocolpopexy, and bladder neck reconstruction was performed. However, eversion recurred 10 months postoperatively. Subsequently, robotic Burch colposuspension, cystopexy to the rectus fascia, bladder neck reconstruction, colpoclesis, and cystostomy were performed. There was no recurrence postoperatively.

Conclusion

Robotic Burch colposuspension, cystopexy to the rectus fascia, bladder neck reconstruction, colpoclesis, and cystostomy were performed for complete bladder eversion.

A case of direct inguinal hernia incarceration after transperitoneal robot-assisted radical prostatectomy

In this study, we report a case of incarcerated direct inguinal hernia (DIH) after robot-assisted radical prostatectomy (RARP) in a patient with concomitant DIH. The 71-year-old man underwent RARP. Six days later, he developed a right DIH incarceration. His laparoscopy findings revealed an incarcerated intestine that was adherent to the hernia orifice. After reducing the hernia, the peritoneum was found to be defective in the right DIH orifice. The DIH was then repaired via the Lichtenstein method. The patient was discharged without complications on postoperative day 13. No recurrence was observed at 3-year follow-up. When repair and peritoneum closure for concomitant DIH are not performed in RARP, it should be kept in mind that the nonrepaired concomitant DIH orifice may develop intestinal incarceration and adhesion to the hernia orifice without the peritoneum immediately after RARP.

Novel Intraoperative Navigation Using Ultra-High-Resolution CT in Robot-Assisted Partial Nephrectomy

Simple Summary

Successful surgery in robot-assisted partial nephrectomy (RAPN), especially for highly complex tumors, relies on a detailed understanding of the anatomical relations of the tumor absolute and relative to the urinary tract and the vascular structures, including the renal pedicle. Intraoperative navigation with accurate information regarding tumor position relative to the surrounding urinary vascular structures undoubtedly assists the surgeon during RAPN. In this report, we performed RAPN with intraoperative navigation using a novel computed tomography scanner (UHR-CT) and compared its perioperative and short-term functional outcomes to those of area-detector CT (ADCT). We found that this novel navigation system using UHR-CT provided a shorter warm ischemia time and lower estimated blood loss than ADCT, and concluded this could be a useful tool for patients who undergo RAPN. This is the first report to evaluate the feasibility and usefulness of UHR-CT for intraoperative navigation during RAPN.

Abstract

To assess the perioperative and short-term functional outcomes of robot-assisted partial nephrectomy (RAPN) with intraoperative navigation using an ultra-high-resolution computed tomography (UHR-CT) scanner, we retrospectively analyzed 323 patients who underwent RAPN using an UHR-CT or area-detector CT (ADCT). Perioperative outcomes and the postoperative preservation ratio of estimated glomerular filtration rate (eGFR) were compared. After the propensity score matching, we evaluated 99 patients in each group. Although the median warm ischemia time (WIT) was less than 25 min in both groups, it was significantly shorter in the UHR-CT group than in the ADCT group (15 min vs. 17 min, p = 0.032). Moreover, the estimated blood loss (EBL) was significantly lower in the UHR-CT group than in the ADCT group (33 mL vs. 50 mL, p = 0.028). However, there were no significant intergroup differences in the postoperative preservation ratio of eGFR at 3 or 6 months of follow-up (ADCT 91.8% vs. UHR-CT 93.5%, p = 0.195; and ADCT 91.7% vs. UHR-CT 94.0%, p = 0.160, respectively). Although no differences in short-term renal function were observed in intraoperative navigation for RAPN in this propensity score–matched cohort, this study is the first to demonstrate that UHR-CT resulted in a shorter WIT and lower EBL than ADCT.

Perioperative and long-term functional outcomes of robot-assisted versus open partial nephrectomy: A single-center retrospective study of a Japanese cohort

Objective

This study aimed to compare the perioperative and long-term functional outcomes between robot-assisted partial nephrectomy (RAPN) and open partial nephrectomy (OPN) in Japanese patients.

Methods

We retrospectively analyzed 242 patients who underwent either RAPN or OPN between 2007 and 2017 at our hospital. Propensity score matching was carried out between the two groups at a ratio of 1:1. Perioperative outcomes and postoperative estimated glomerular filtration rates (eGFR) were compared at one and three years of follow-up.

Results

After propensity score matching, we evaluated 39 patients from each group. The ischemia duration of the RAPN group was significantly shorter than that of the OPN group (18 vs. 24, p < 0.001). Moreover, the estimated blood loss (EBL) was significantly lower in the RAPN group than in the OPN group (50 vs. 174, p < 0.001). However, there were no significant differences in the postoperative eGFR between the two groups at one or three years of follow-up (OPN 54.8 vs. RAPN 61.2, p = 0.109, and OPN 54.8 vs. RAPN 55.5, p = 0.262, respectively).

Conclusion

RAPN resulted in shorter ischemia durations and lower rates of EBL than did OPN; however, no differences in long-term renal function were observed between RAPN and OPN in our propensity-score matched Japanese cohort.

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This study aimed to compare the perioperative and long-term functional outcomes of RAPN and OPN in Japanese patients.

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RAPN resulted in shorter ischemia durations and lower rates of estimated blood loss than OPN.

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No differences in long-term renal function were observed between RAPN and OPN.

Risk factors for postoperative ileus after robot-assisted radical cystectomy with intracorporeal urinary diversion

OBJECTIVES

To evaluate the risk factors for postoperative ileus in patients who underwent robot-assisted radical cystectomy with intracorporeal urinary diversion.

METHODS

We retrospectively analyzed 78 patients with bladder cancer who underwent robot-assisted radical cystectomy with intracorporeal urinary diversion at Fujita Health University between 2011 and 2021. Baseline characteristics and perioperative outcomes were compared between the cohorts with and without ileus. Logistic regression analysis was used to identify the risk factors for postoperative ileus.

RESULTS

Out of the 78 patients included in this study, 20 (25.6%) developed postoperative ileus. The ileus cohort was associated with a significantly lower Geriatric-8 score (P = 0.003) and a higher rate of previous abdominal/pelvic surgery (P = 0.04) compared with those of the nonileus cohort. Significantly longer intestinal tract reconstruction time, hospital stay, time to mobilization, fluid intake, solid intake, flatus, and stool were observed in the ileus cohort. According to the results of the logistic regression analysis, the Geriatric-8 sum (P = 0.009), time to mobilization (P = 0.03), and time to fluid intake (P = 0.004) were independent predictors of postoperative ileus. In the model predicting postoperative ileus, the area under the receiver operating characteristic curve was 0.716, and the cutoff value of the Geriatric-8 sum was 13.

CONCLUSIONS

Early mobilization and fluid intake and low Geriatric-8 scores were significant risk factors for postoperative ileus. Preoperative Geriatric-8 evaluation is a useful tool for predicting postoperative ileus. Comprehensive enhanced recovery after surgery, including key components, may help bowel recovery and prevent subsequent ileus.

Predictors of Secondary Bladder Cancer in Patients with Prostate Cancer Treated with Brachytherapy: A Single-institution Study of a Japanese Cohort

PURPOSE

The incidence of secondary bladder cancer after treatment for localized prostate cancer (PCa) remains unclear. In this study, PCa cases treated with brachytherapy (BT) were evaluated to assess the incidence of a second malignancy of bladder cancer in a Japanese cohort.

MATERIALS AND METHODS

Overall, 969 patients treated with BT at our hospital between July 2006 and January 2019 were included in the study cohort. The incidence and predictors of secondary bladder cancer were also assessed.

RESULTS

The incidence of secondary bladder cancer was 1.5% (n = 14). Of the seven factors (age, pretreatment PSA, Gleason score, cTNM stage, prostate volume, total activity, and combined external beam), prostate volume and total activity showed significant differences between the cohorts with and without secondary bladder cancer (P = .03 and P = .001, respectively). Upon comparison of the seven parameters for the 969 patients treated with BT, we found that only the total activity factor was affected by the incidence of secondary bladder cancer in the multivariate analysis (P = .007).

CONCLUSION

The incidence of secondary bladder cancer was evaluated after BT for PCa. Total activity was associated with the incidence of secondary bladder cancer in Japanese patients who received BT.

Intra-corporeal robot-assisted versus open radical cystectomy: a propensity score-matched analysis comparing perioperative and long-term survival outcomes and recurrence patterns

BACKGROUND

To compare perioperative and long-term oncological outcomes and recurrence patterns between robot-assisted radical cystectomy with intra-corporeal urinary diversion (iRARC) and open radical cystectomy (ORC).

METHODS

We retrospectively analyzed 177 bladder cancer patients who received iRARC or ORC at Fujita Health University between 2008 and 2020. Our primary endpoint was long-term oncological outcomes. As a secondary endpoint, we examined perioperative outcomes, complications, and recurrence patterns. These outcome measures were compared between the propensity score (PS)-matched cohorts.

RESULTS

PS-matched analysis resulted in 60 matched pairs from iRARC and ORC groups. The iRARC cohort was associated with significantly longer operative time (p = 0.02), lower estimated blood loss (p < 0.001), lower blood transfusion rate (p < 0.001), shorter length of hospital stay (p < 0.001), fewer overall complications (p = 0.03), and lower rate of postoperative ileus (p = 0.02). There was no statistically significant difference between iRARC and ORC in 5-year RFS (p = 0.46), CSS (p = 0.63), and OS (p = 0.71). RFS and CSS were also comparable, even in locally advanced (≥ cT3) disease. Multivariate analysis identified lymphovascular invasion as a robust predictor of RFS, CSS, and OS. The number of recurrence was similar between the groups, while extra-pelvic lymph nodes were more frequent in iRARC than that in ORC (22.7% vs. 7.7%).

CONCLUSIONS

iRARC has favorable perioperative outcomes, fewer complications, and comparable long-term survival outcomes, including locally advanced (≥ cT3) disease, compared to that in ORC. Our results need to be validated in prospective randomized clinical trials.

Tryptophan 2,3-dioxygenase in tumor cells is associated with resistance to immunotherapy in renal cell carcinoma

Indoleamine 2,3‐dioxygenase 1 (IDO1) is a key enzyme associated with immunomodulation through its regulation of the tryptophan‐kynurenine (Kyn) pathway in advanced cancers, including metastatic renal cell carcinoma (mRCC). However, the failure of IDO1 inhibitors when used in combination with immune checkpoint inhibitors (ICIs), as observed in clinical trials, raises a number of questions. This study aimed to investigate the association of tryptophan 2,3‐dioxygenase (TDO) and IDO1 with cancer development and resistance to immunotherapy in patients with RCC. In our analysis of RCC tissue samples, tissue Kyn levels were elevated in advanced‐stage RCC and correlated well with TDO expression levels in RCC tumor cells. In patients with mRCC, TDO rather than IDO1 was expressed in RCC tumor cells, showing a strong association with Kyn expression. Furthermore, immunohistochemical staining of TDO was strongly associated with the staining intensity of forkhead box P3, as well as ICI therapy response and survival in patients with mRCC. Our study is the first to show that TDO expression in tumor tissues is associated with progression and survival, confirming its potential as a predictive biomarker of primary resistance to immunotherapy in patients with mRCC. Our findings suggest that strategies aimed at inhibiting TDO, rather than IDO1, in combination with ICI therapy may aid in the control of mRCC progression.

Long-Term Functional and Oncologic Outcomes of Robot-Assisted Partial Nephrectomy for Cystic Renal Tumors: A Single-Center Retrospective Study

Objectives: To evaluate the outcomes of robot-assisted partial nephrectomy (RAPN) in cystic renal tumors. Materials and Methods: We retrospectively analyzed patients who underwent RAPN for either cystic (n = 46) or solid (n = 271) renal tumors at Fujita Health University between 2010 and 2019. Cystic renal tumors were diagnosed using cross-sectional imaging. Perioperative, oncologic, and functional outcomes were assessed. Results: The median follow-up periods were 38, 41, and 37 months in the total, cystic, and solid groups, respectively. Most patient characteristics were similar among both groups, while the median age of the cystic group was significantly lower than that of the solid group (p = 0.02). Most perioperative variables and complications were comparable between the two groups. There was no significant difference between the groups in perioperative renal function. The estimated glomerular filtration rate preservation rates were 93.1% and 89.2% in the cystic and solid groups, respectively (p = 0.17). The cystic group showed a higher benign histology rate (19.6% vs 7%) and lower Fuhrman grade than the solid group (24.3% vs 15.1% in grade 1, and 73% vs 81.3% in grade 2), although there was no statistically significant difference between the two groups. In the solid group, 10 patients (3.7%) experienced recurrence, and 2 patients (0.7%) died of renal-cell carcinoma, while none of the patients with cystic tumors experienced recurrence. There was no statistically significant difference between the cystic and solid tumors with respect to 5-year recurrence-free survival (p = 0.18), cancer-specific survival (p = 0.55), and overall survival (p = 0.35). Conclusions: RAPN for cystic renal tumors appears to be safe and feasible with perioperative, long-term functional and oncologic outcomes comparable with those in solid tumors. RAPN can be a safe and effective surgical option for cystic renal tumors.

Two cycles of neoadjuvant chemotherapy improves survival in patients with high-risk upper tract urothelial carcinoma

OBJECTIVES

To assess the impact of two cycles of neoadjuvant chemotherapy (NAC) in patients who underwent nephroureterectomy for high-risk cN0M0 upper tract urothelial carcinoma (UTUC), and to evaluate the efficacy of NAC in patients with localised disease (≤cT2).

PATIENTS AND METHODS

We retrospectively analysed patients with high-risk cN0M0 UTUC who received NAC followed by surgery, compared with a matched cohort who underwent initial surgery at Fujita Health University during 2005-2019. Baseline and tumour characteristics, overall survival (OS), cancer-specific survival (CSS), and recurrence-free survival (RFS) were compared between the cohorts. Cox proportional hazards models were used to identify predictors of survival.

RESULTS

There were 117 and 67 patients in the study group and the control group, respectively. Significantly higher pathological downstaging (pDS) and lower lymphovascular invasion (LVI) were observed in the study group than in the control group (48% vs 22%, P = 0.008 and 29% vs 46%, P = 0.045, respectively). The NAC group had significantly better 5-year OS (79% vs 53%, P = 0.003), 5-year CSS (84% vs 66%, P = 0.008), and 5-year RFS (80% vs 61%, P = 0.001) than the control group. The OS benefit of NAC was observed even in patients with localised (≤cT2) disease (P = 0.019). Patients with LVI showed significantly worse CSS both in pathologically locally advanced (≥pT3) and in localised (≤pT2) tumours (P = 0.048 and P = 0.018, respectively). Multivariate analysis identified LVI, NAC, and pDS as independent predictors of OS. Male sex and post-NAC LVI were identified as predictors of worse survival in patients who underwent NAC.

CONCLUSIONS

Two cycles of NAC improved the survival of patients with high-risk UTUC, even in patients with localised disease. Although two cycles of NAC appear to be effective in cN0M0 high-risk UTUC including localised disease, additional larger sample size multicentre prospective studies comparing short-course NAC regimens followed by surgery and surgery alone are required.

Deep learning using preoperative magnetic resonance imaging information to predict early recovery of urinary continence after robot-assisted radical prostatectomy

OBJECTIVES

To investigate whether a deep learning model from magnetic resonance imaging information is an accurate method to predict the risk of urinary incontinence after robot-assisted radical prostatectomy.

METHODS

This study included 400 patients with prostate cancer who underwent robot-assisted radical prostatectomy. Patients using 0 or 1 pad/day within 3 months after robot-assisted radical prostatectomy were categorized into the "good" group, whereas the other patients were categorized into the "bad" group. Magnetic resonance imaging DICOM data, and preoperative and intraoperative covariates were assessed. To evaluate the deep learning models from the testing dataset, their sensitivity, specificity and area under the receiver operating characteristic curve were analyzed. Gradient-weighted class activation mapping was used to visualize the regions of deep learning interest.

RESULTS

The combination of deep learning and naive Bayes algorithm using axial magnetic resonance imaging in addition to clinicopathological parameters had the highest performance, with an area under the receiver operating characteristic curve of 77.5% for predicting early recovery from post-prostatectomy urinary incontinence, whereas machine learning using clinicopathological parameters only achieved low performance, with an area under the receiver operating characteristic curve of 62.2%. The gradient-weighted class activation mapping methods showed that deep learning focused on pelvic skeletal muscles in patients in the good group, and on the perirectal and hip joint regions in patients in the bad group.

CONCLUSIONS

Our results suggest that deep learning using magnetic resonance imaging is useful for predicting the severity of urinary incontinence after robot-assisted radical prostatectomy. Deep learning algorithms might help in the choice of treatment strategy, especially for prostate cancer patients who wish to avoid prolonged urinary incontinence after robot-assisted radical prostatectomy.

Combined α-methylacyl-CoA racemase inhibition and docetaxel treatment reduce cell proliferation and decrease expression of heat shock protein 27 in androgen receptor-variant-7-positive prostate cancer cells

Background

Disease progression in castrate-resistant prostate cancer (PCa) is most commonly driven by the reactivation of androgen receptor (AR) signaling and involves AR splice variants including ARV7.

Materials and methods

We used the ARV7-positive PCa cell line, 22Rv1, to study the relationship of the PCa marker α-methylacyl-CoA racemase (AMACR), AR, and ARV7 in PCa.

Results

Docetaxel addition but not AMACR inhibition decreased the proliferation of 22Rv1 cells. The combination of AMACR inhibition and docetaxel treatment resulted in a maximum reduction of cell proliferation. The Western blotting analysis revealed that both AR and ARV7 expression were significantly decreased with the use of charcoal-stripped serum following AMACR inhibition and docetaxel treatment. AMACR inhibition and docetaxel treatment in the charcoal-stripped serum condition reduced the proliferation of 22Rv1, possibly via the downregulation of the heat shock protein 27.

Conclusion

Using cell proliferation and Western blot analysis, we demonstrated that AMACR inhibition and docetaxel treatment, under androgen deprivation conditions, significantly reduced the proliferation of ARV7 positive cancer cells and decreased the levels of AR and ARV7 expression, possibly via downregulation of heat shock protein 27.

Predictors for trifecta achievement of robot-assisted partial nephrectomy in high-complexity tumors (Preoperative Aspects and Dimensions Used for an Anatomical score ≥10)

INTRODUCTION

Robot-assisted partial nephrectomy (RAPN) is emerging as an effective treatment oncologically and functionally for clinically localized renal tumors. However, RAPN in high-complexity tumors with a Preoperative Aspects and Dimensions Used for an Anatomical score ≥10 remains challenging. In this study, the feasibility of RAPN for high-complexity tumors was assessed.

METHODS

The study cohort consisted of 177 cases with clinically localized renal cell carcinoma who had undergone RAPN at our hospital from July 2010 to February 2018. They were assessed for perioperative parameters and trifecta achievement (ie, negative surgical margins, warm ischemia time <25 minutes, and no complications).

RESULTS

Among the 177 cases who had undergone RAPN, 60 had high-complexity tumors, and 117 had non-high-complexity (ie, intermediate- or low-complexity) tumors. There were no significant differences in the operative and console times between the cohorts, but estimated intraoperative blood loss was much lower in the non-high-complexity group. Although the average warm ischemia time was less than 25 minutes in both groups, it was significantly shorter in the non-high-complexity group. Trifecta achievement rates significantly differed between the high- and non-high-complexity groups (68.3% vs 86.3%). Comparisons of four operative parameters (ie, BMI, tumor size, endophytic properties, and hilar tumor) using univariate analysis in the 60 high-complexity tumor cases showed that BMI and tumor size were independent factors (P = 0.05 and 0.018, respectively). In multivariate analysis, tumor size was the only factor directly associated with trifecta achievement (P = 0.029).

CONCLUSION

The trifecta achievement rate was significantly lower in the high-complexity group. Only tumor size affected trifecta achievement during RAPN in cases with high-complexity tumors (Preoperative Aspects and Dimensions Used for an Anatomical score ≥10).

Deep learning using preoperative MRI information to predict early recovery of urinary continence after robot-assisted radical prostatectomy

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Background: Urinary incontinence remains one of the most bothersome postoperative complications even after robot-assisted radical prostatectomy (RARP). We aimed to make a novel prediction system that can be used preoperatively to inform patients of the accuracy of early recovery of urinary continence after RARP using a deep learning (DL) model from magnetic resonance imaging (MRI) information and preoperative clinicopathological parameters. Methods: A retrospective cohort study was conducted on prostate cancer (PC) patients who had undergone RARP at our hospital between August 2015 and July 2019. Patients using no pads/no leakage of urine or the use of a safety pad within 3 months after RARP is categorized into “good” continence and others into “no good” continence. MRI DICOM data from axial, coronal and sagittal imaging as well as preoperative clinicopathological covariates (age, BMI, prostate volume, serum PSA level, Gleason score, clinical stage) were assessed. Supervised DL algorithms, which included AdaBoost, Naive Bayes, Neural Network, Random Forest, and SVM were trained and tested as binary classifiers (good or no good). To evaluate the DL models from the testing data set, their sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), as well as area under the receiver operating characteristic curve (AUC) were analyzed. Results: Data were available for 497 patients in the study period. The AdaBoost DL algorithm using MRI information in addition to clinicopathological parameters had the highest performance with sensitivity at 92%, specificity at 77%, PPV at 79%, NPV at 91%, and AUC at 84% for predicting good continence, while that using clinicopathological parameters only had the performance with sensitivity at 50%, specificity at 69%, PPV at 60%, NPV at 60%, and AUC at 60%. Conclusions: Our results suggest that the DL algorithms using MRI imaging information are highlighted as an accurate method for strongly predicting early recovery of urinary continence after RARP. Thus, DL predictions may help allocation of treatment strategies for PC patients who dislike prolonged urinary incontinence after RARP.

The efficacy of two cycles of neoadjuvant chemotherapy for upper tract urothelial carcinoma patients

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Background: Upper tract urothelial carcinoma (UTUC) is frequently upstaged after surgery and is associated with poor prognosis. However, the efficacy of neoadjuvant chemotherapy (NAC) and optimal No. of NAC cycles for UTUC have been poorly defined. In this study, we evaluated if two cycles of NAC improves survival of UTUC patients in our institute. Methods: A total of 167 patients who underwent radical nephroureterectomy at Fujita Health University between November 2005 and December 2018 were retrospectively analyzed. The study group comprised 114 patients with UTUC who received NAC followed by surgery. The control group consisted of 53 patients who underwent initial surgery without NAC. We compared two groups in overall survival (OS), cancer specific survival (CSS), recurrence free survival (RFS, urinary tract, visceral) and independent prognostic factors. Kaplan-Meier methods, log-rank test and cox proportional-hazards models were used for statistical analysis. Results: Median follow up was 1108 days, and there were no significant differences in preoperative patient characteristics between NAC group and initial surgery (IS) group. NAC had significantly improved 5-year OS (75% vs 55%, p=0.004) and 5-year CSS (84% vs 65%, p=0.024). That is more significant in the analysis with cT3 patients (p=0.0002). NAC also significantly improved visceral RFS (p=0.001). However, NAC does not affect urinary tract RFS (p=0.96) when compared to IS. pDS were observed in 55 out of 114 (48%) in NAC group, and 12 out of 53 (22%) in IS group. Comparison of OS between with pDS and without pDS demonstrated significantly better OS in with pDS group (p=0.0001). Multivariate cox proportional-hazards models identified NAC, pDS, resection margin, pN and cT3 as independent prognostic factors for OS. Conclusions: Two cycles of NAC induced pDS and improved survival of UTUC patients. Reduced number of NAC cycles may offer clinical benefits of low chemo-associated toxicity, appropriate surgery without delay in chemo-resistant case and sufficient cancer regression with pDS.

P5417Splenic volume changes as a hemodynamic parameter in advanced heart failure with left ventricular assist device

Background

The spleen has been recognized as an important organ to reserve 20–30% of the total blood volume. Generally, splenomegaly has been thought to be related to congestion. However, in the setting of hypovolemic shock or hypoxemia, it has been reported that spleen contracted and splenic volume decreased. On the other hand, in advanced heart failure (HF), the hemodynamics is characterized by both low cardiac output (LO) and systemic congestion, and patients sometimes need support of left ventricular assist device (LVAD). However, it remains unclear about the association between spleen size and hemodynamic parameters in patients with LO who need LVAD support.

Purpose

The purpose of this study was to investigate the relationship between spleen size and hemodynamic parameters in advanced HF before and after LVAD implantation.

Methods

We enrolled 12 advanced HF patients with LVAD (11 males, 45±10 years). All patients underwent blood test, echocardiography, right heart catheterization, and computed tomography (CT) before and after LVAD implantation. Spleen size was measured by CT volumetry. We excluded patients with splenic infarction, or any infections, or mean right atrial pressure (RAP) <5mmHg because of a possibility of hypovolemic status. LO was defined as CI less than 2.2L/min/m2.

Results

At pre- and post-LVAD implantation, cardiac output, cardiac index (CI), mean RAP, and mean pulmonary capillary wedge pressure were 3.1±0.6 vs. 4.9±0.9L/min, p=0.002; 1.7±0.3 vs. 2.8±0.3L/min/m2, p=0.002; 14±5 vs. 9±3mmHg, p=0.059; and 30±7 vs. 10±3mmHg, p=0.002, respectively. The serum brain natriuretic peptide level had significantly decreased (1101 [517–1446] vs 74 [35–216] pg/mL, p=0.002). In all patients, CI had increased to over 2.2L/min/m2. The splenic volume significantly increased from pre- to post-LVAD implantation (172±48 vs. 233±78mL, p=0.002) (Figure). Furthermore, all patients were divided into two groups; elevated RAP group (n=4) and non-elevated RAP group (n=8) after LVAD support. In elevated RAP group, there were no significant changes in the spleen size between pre- and post-LVAD implantation (167±45 vs. 223±111mL, p=0.068). On the other hand, in non-elevated RAP group, the spleen volume had significantly increased from pre- to post-LVAD support (172±53 vs. 231±62mL, p=0.011). In addition, there was one patient whose hemodynamic state had changed to LO again because of LVAD failure due to pump thrombosis. In this case, the splenic volume was 212mL before LVAD implantation with LO, and increased to 418mL after LVAD implantation with non-LO, although decreased to 227mL after LVAD pump failure with LO again.

Splenic volume changes

Conclusions

The spleen may change its size in order to keep cardiac output by regulating cardiac preload depending on the systemic perfusion in advanced HF with LVAD.

Acknowledgement/Funding

None

Clinical and oncological outcomes of robot-assisted radical prostatectomy with nerve sparing vs. non-nerve sparing for high-risk prostate cancer cases

Robot-assisted radical prostatectomy (RARP) is one of the most widely used procedures for localized prostate cancer (PCa). In the present study, the clinical and oncological outcomes of RARP with bilateral or unilateral nerve sparing (NS) for D'Amico high-risk PCa cases were assessed. Among the 767 cases who received RARP at Fujita Health University Hospital between August 2009 and December 2016, 230 high-risk PCa cases who were observed for >6 months comprised the retrospective study cohort. Bilateral NS was performed with the bilateral neurovascular bundle in eight, unilateral in 125 and none in 97 cases. Perioperative parameters [surgery time, console time, estimated blood loss, pathological stage, positive lymph node metastases [pN (+)], and surgical margin positivity] did not exhibit significant differences between the NS and non-NS cohorts. During a median follow-up time of 25 months, the 1- and 3-year biochemical recurrence (BCR)-free survival rates in the NS/non-NS cohorts were 84.4/86.0 and 72.7/75.0%, respectively. There were no significant differences identified between the two groups at each time period. According to multivariate analysis, the resection margin was an important factor for time to BCR, regardless of the NS technique used. The numbers of pads used daily at 3 and 6 months after RARP between the NS/non-NS cohorts were 1.1/1.5 and 0.6/1.0, respectively (P=0.045 and P=0.009), suggesting that the NS technique resulted in significantly improved outcomes regarding urinary continence recovery. In selected high-risk PCa cases, the NS technique resulted in equivalent oncological outcomes and improved urinary continence compared with the non-NS RARP group.

[Robotic Surgery for Urologic Malignancy - Prostate, Kidney and Bladder]

Robotic-assisted surgery has been wide-spreading rapidly as a technique to develop laparoscopic surgery by innovative technological improvement such as high magnifided 3D-image and multi-degree freedom of forceps, leading to safety enhancement and better functional recovery. Robotic surgery in the urological field made it possible to highly fine operation in a narrow field, such as pelvic cavity or retroperitoneal space. Better outcomes were recognized especially in perioperative complications and postoperative QOL recovery than other procedures like open or laparoscopic. According to these results, radical prostatectomy, partial nephrectomy and radical cystectomy were approved for health insurance coverage in 2012, 2016 and 2018, respectively. Robotic-assistance has definitely brought a paradigm shift in urologic surgery. The application to more and more a variety of procedure and the improvement of treatment outcomes are expected in the future.

The Olfactory Transcriptome and Progression of Sexual Maturation in Homing Chum Salmon Oncorhynchus keta

Reproductive homing migration of salmonids requires accurate interaction between the reception of external olfactory cues for navigation to the spawning grounds and the regulation of sexual maturation processes. This study aimed at providing insights into the hypothesized functional link between olfactory sensing of the spawning ground and final sexual maturation. We have therefore assessed the presence and expression levels of olfactory genes by RNA sequencing (RNAseq) of the olfactory rosettes in homing chum salmon Oncorhynchus keta Walbaum from the coastal sea to 75 km upstream the rivers at the pre-spawning ground. The progression of sexual maturation along the brain-pituitary-gonadal axis was assessed through determination of plasma steroid levels by time-resolved fluoroimmunoassays (TR-FIA), pituitary gonadotropin subunit expression and salmon gonadotropin-releasing hormone (sgnrh) expression in the brain by quantitative real-time PCR. RNAseq revealed the expression of 75 known and 27 unknown salmonid olfactory genes of which 13 genes were differentially expressed between fish from the pre-spawning area and from the coastal area, suggesting an important role of these genes in homing. A clear progression towards final maturation was characterised by higher plasma 17α,20β-dihydroxy-4-pregnen-3-one (DHP) levels, increased pituitary luteinizing hormone β subunit (lhβ) expression and sgnrh expression in the post brain, and lower plasma testosterone (T) and 17β-estradiol (E2) levels. Olfactomedins and ependymin are candidates among the differentially expressed genes that may connect olfactory reception to the expression of sgnrh to regulate final maturation.

Diurnal changes in salmon GnRH secretion in the brain of masu salmon (Oncorhynchus masou)

The day-night changes of salmon GnRH (sGnRH), which is secreted from various brain regions, were analyzed in maturing and matured masu salmon (Oncorhynchus masou). In maturing males, the levels of sGnRH secreted from the olfactory bulb (OB), terminal nerve (TN), and ventral telencephalon and preoptic area (VT+POA) were all significantly higher during midnight than daytime. However, the contents of sGnRH in the pituitary gland during midnight were not higher than those during daytime. In maturing females, the levels of sGnRH secreted from the VT+POA were higher during midnight than daytime, and the contents of sGnRH in the pituitary gland were also higher during midnight. In matured fish, the levels of sGnRH secreted from the OB, TN and VT+POA during midnight were significantly higher than those during daytime. There were also no significant differences in the contents of sGnRH in the pituitary gland. These results suggest that a short photoperiod may be involved in diurnal secretion rhythms of sGnRH in various brain regions and the pituitary gland.

Insertion of a suicide gene into an immortalized human hepatocyte cell line

For developing a bioartificial liver (BAL) device, an attractive alternative to the primary human hepatocytes would be the use of highly differentiated immortalized human hepatocytes with a safeguard. To test the feasibility, the primary human hepatocytes were immortalized by a plasmid SV3neo encoding simian virus 40 large T antigen (SV40Tag) gene. A highly differentiated hepatocyte line OUMS-29 was established. A suicide gene of herpes simplex virus-thymidine kinase (HSV-TK) was retrovirally introduced into OUMS-29 cells as a safeguard for clinical application. One of the resulting HSV-TK-positive cell lines, OUMS-29/tk, grew in chemically defined serum-free medium with the gene expression of differentiated liver functions. OUMS-29/tk cells were 100 times more sensitive to ganciclovir compared with unmodified OUMS-29 cells in in vitro experiments. We have established a tightly regulated immortalized human hepatocyte cell line. Essentially unlimited availability of OUMS-29/tk cells may be clinically useful for BAL therapy.

Expression of E-cadherin-catenin complex in human benign schwannomas

The Ca2+-dependent cell adhesion molecule E-cadherin has been known to express in normal and reactive Schwann cells in rodents, and to play an important role in Schwann cell-Schwann cell adhesion and maintenance of peripheral nervous tissue architecture. However, little is known about expression of E-cadherin in schwannomas. The aim of the present study was to investigate the cellular expression and localization of E-cadherin, and its associated protein, alpha E-, alpha N- and beta-catenins in human schwannomas, which are supposed to derive from Schwann cells. We tested the hypothesis that these proteins might show an altered expression/distribution in schwannoma cells which correlates with their neoplastic behavior, including sparse cell-cell contact, as seen those in meningiomas and various carcinomas. In human schwannomas, however, E-cadherin, alpha E-catenin, and beta-catenin were detected by western blotting and immunohistochemistry, whereas alpha N-catenin was not. Immunoprecipitation using anti-E-cadherin antibody resulted in alpha E-catenin forming a complex with E-cadherin. SSCP analysis revealed no mutations in the transmembrane domain or in intracellular catenin-binding site of E-cadherin. These data suggest that the E-cadherin-alpha E-catenin complex is well preserved in human schwannoma cells, which is compatible with its benign behavior, and these molecules might be used as additional cell markers of Schwann cell-derived tumors.

Reactivation of liver-specific gene expression in an immortalized human hepatocyte cell line by introduction of the human HNF4alpha2 gene

An immortalized human hepatocyte cell line (OUMS-29) was established from fetal liver by transfection with the SV-40 large T antigen gene that has certain liver-specific functions such as albumin production and enzyme activities of CYP1A1, 1A2, and 2E1. To make OUMS-29 cells express other liver-specific functions, the human hepatocyte nuclear factor 4alpha2 (HNF4alpha2) gene was introduced into the cells, because this gene was found to be markedly down-regulated. The transduced HNF4alpha2 was overexpressed in the nuclei of the transfected cells, and its DNA-binding activity was also detected. The liver-specific genes such as apolipoprotein AI, CII, CIII, blood coagulation factor X, alpha1-antitrypsin, and HNF1alpha were up-regulated. Thus, this cell line is expected to be a useful tool for studying the differentiated human hepatocyte functions.

Establishment of a human hepatocyte line (OUMS-29) having CYP 1A1 and 1A2 activities from fetal liver tissue by transfection of SV40 LT

Immortalized human hepatocytes that can retain functions of drug-metabolizing enzymes would be useful for medical and pharmacological studies and for constructing an artificial liver. The aim of this study was to establish immortalized human hepatocyte lines having differentiated liver-specific functions. pSVneo deoxyribonucleic acid, which contains large and small T genes in the early region of simian virus 40, was introduced into hepatocytes that had been obtained from the liver of a 21-wk-old fetus. Neomycin-resistant immortalized colonies were cloned and expanded to mass cultures to examine hepatic functions. Cells were cultured in a chemically defined serum-free medium, ASF104, which contains no peptides other than recombinant human transferrin and insulin. As a result, an immortal human hepatocyte cell line (OUMS-29) having liver-specific functions was established from one of the 13 clones. Expression of CYP 1A1 and 1A2 messenger ribonucleic acid by the cells was induced by treatment with benz[a]pyrene, 3-methylcholanthrene, and benz[a]anthracene. OUMS-29 cells had both the polycyclic aromatic hydrocarbon receptor (AhR) and AhR nuclear translocator. Consequently 7-ethoxyresorufin deethylase activity of the cells was induced time- and dose-dependently by these polycyclic aromatic hydrocarbons. This cell line is expected to be instrumental as an alternative method in animal experiments for studying hepatocarcinogenesis, drug metabolisms of liver cells, and hepatic toxicology.

Treatment of surgically induced acute liver failure with transplantation of highly differentiated immortalized human hepatocytes

Primary human hepatocytes are an ideal source of hepatic function in bioartficial liver (BAL), but the shortage of human livers available for hepatocyte isolation limits this modality. To resolve this issue, primary human fetal hepatocytes were immortalized using simian virus 40 large T antigen. One of the immortal cell lines, OUMS-29, showed highly differentiated liver functions. Intrasplenic transplantation of OUMS-29 cells protected 90% hepatectomized rats from hyperammonemia and significantly prolonged their survival. Essentially unlimited availability of OUMS-29 cells supports their clinical use for BAL treatment.

Transplantation of highly differentiated immortalized human hepatocytes to treat acute liver failure

BACKGROUND

Temporary support of a damaged liver by a bioartificial liver (BAL) devise is a promising approach for the treatment of acute liver failure. Although human primary hepatocytes are an ideal source of hepatic function in BAL, shortage of human livers available for hepatocyte isolation is the limiting factor for the use of this modality. A clonal human hepatocyte cell line that can grow economically in culture and exhibit liver-specific functions should be an attractive solution to this problem.

METHODS

To test this alternative, primary human fetal hepatocytes were immortalized using Simian virus 40 large T antigen. To investigate the potential of the immortalized cells for BAL, we transplanted the cells into the spleen of adult rats and performed a 90% hepatectomy 12 hr later.

RESULTS

One of the cloned human liver cell lines, OUMS-29, showed highly differentiated liver functions. Intrasplenic transplanting of 20x10(6) OUMS-29 cells protected the animals from hyperammonemia and the associated hepatic encephalopathy. Survival was significantly prolonged in 90% of hepatectomized rats receiving OUMS-29 cells.

CONCLUSIONS

A highly differentiated immortalized human hepatocyte cell line, OUMS-29, was able to provide metabolic support during acute liver failure induced by 90% hepatectomy in rats. Essentially unlimited availability of OUMS-29 cells may be clinically useful for BAL treatment.

Ubiquitous presence of cellular proteins that specifically bind to the 3' terminal region of hepatitis C virus

The 3' terminal region (3'-X tail) of hepatitis C virus (HCV) genomic RNA forms a stable stem-loop structure. The 3'-X tail consists of 98 nucleotides (nt) that are highly conserved among the HCV strains and supposed to function as a cis-acting region for replication of negative strand RNA and/or viral encapsidation. In the present study, by UV cross-linking assay we found two kinds of cellular proteins of approximately 87 and 130 kDa, which specifically bind to the full-length 3'-X tail (nt 1 to 98), but not the 3'- or 5'-truncated 3'-X tail, consisting of nt 1 to 50 or nt 51 to 98, respectively. These proteins were detected in human cell lines such as hepatic tumor cell lines and a T-lymphocyte cell line and also in a human embryonic lung fibroblast cell strain. In addition, human hepatocellular carcinoma tissues expressed these proteins regardless of infection or uninfection of HCV. Furthermore, these proteins were also detected in normal human tissues derived from the lung, heart, kidney, stomach, intestine, and colon. Thus, these cellular proteins, which are ubiquitously present in human tissues, might be involved in viral replication and/or encapsidation.

Massive culture of human liver cancer cells in a newly developed radial flow bioreactor system: ultrafine structure of functionally enhanced hepatocarcinoma cell lines

With a view to initiating clinical trials, cell morphology and function for a newly developed artificial liver support system employing highly functional human liver cell line, FLC-7, cultured in a radial flow bioreactor were compared to cells grown in a conventional monolayer culture. The radial flow bioreactor consists of a vertically extended cylindrical matrix comprised of porous glass bead microcarriers through which liquid medium flows from the periphery in toward the central axis generating a beneficial concentration gradient of oxygen and nutrients, while preventing excessive shear stresses or buildup of waste products. The three-dimensional culture system supports high-density (1.1 x 10(8) cells/ml-matrix), large scale cultures (4.4 x 10(10) cells/400 ml-bioreactor) with long-term viability. Scanning and transmission electron microscopy (SEM and TEM) revealed that cells cultured in a monolayer system were flattened and extended with numerous cytoplasmic projections. Cells in the three-dimensional culture were spherical and covered with microvillilike processes resembling liver cells in vivo. The cells were solidly attached on the surfaces and within the pores of the microcarriers in highly dense colonies. The spherical cells remained in close contact with adjacent cells, while circulation of liquid medium flowed freely through spaces between cells. FLC-7 cells produced albumin at a rate of 6.41 micrograms/24 h/10(6) cells. Alpha-fetoprotein (AFP) production dropped nearly threefold in comparison to monolayer cultures. Results demonstrated that the new artificial liver support systems (ALSS) provides a superior three-dimensional culture environment that allows cells to perform at naturally functioning levels.

Pyruvate alleviates toxic effects of ethanol on cells in culture

Cytotoxic effects of ethanol on cultured human hepatocytes and fibroblasts differed with the type of culture medium used. When cytotoxic effects of ethanol were compared between culture systems using either RPMI-1640 or Dulbecco's modified Eagle's medium (DMEM), the cytotoxicity was more prominent with the former medium than with the latter. A reduction of the cytotoxic effects appeared to be due to the pyruvate contained in DMEM. The protective effect of pyruvate against ethanol toxicity may be related to tricarboxylic acid (TCA) cycle activity because addition of malate to the medium also reduced the cytotoxic effects. Our results suggest that drug cytotoxicity testing in vitro must be done using various types of culture medium.

Yeast functional assay of the p53 gene status in human cell lines maintained in our laboratory

We used a yeast functional assay (functional analysis of separated alleles in yeast: FASAY) to determine the p53 gene status of human cell lines maintained in our laboratory. This assay enables the researcher to score wild-type p53 expression on the basis of the ability of expressed p53 to transactivate the reporter gene HIS 3 via the p53-responsive GAL 1 promoter in Saccharomyces cerevisiae. The cell lines examined were ten hepatoma, two hepatoblastoma, three in vitro immortalized fibroblast, two osteosarcoma, a chondrosarcoma, an ovarian teratocarcinoma and a colon cancer cell line. Out of 20 cell lines, 11 cell lines had mutations in both alleles of the p53 gene, and another 8 cell lines had no mutation in the p53 gene. Thus, 55% of the cell lines examined had mutations in the p53. Interestingly, PA-1 cells had both the normal and the mutant p53 alleles, showing that FASAY is a useful method for detecting the wild-type and mutated p53 genes simultaneously. As for the three liver cell lines harboring HBsAg, there was no relationship between their p53 gene status and the presence of HBsAg. Two cell lines were normal for p53 status, while the other had a mutation of the p53 gene.

[Rabies virus]

Rabies is not found in Japan at present, but the possibility of invasion of this dangerous infection into Japan always must be kept in mind. In this paper, concerning this disease, epidemiology, infection route to men, pathology, incubation time, general clinical findings, clinical course, various diagnostic methods, differential diagnosis and palliative treatments are described and discussed respectively. Next, prophylaxis using Japanese-make inactivated rabies vaccine derived from chicken embryo are recommended. The property, antibody titer obtained after vaccination, security, a few adverse reaction and a way of preservation, technique of vaccination, contra-indication and miscellaneous articles which should be kept in mind are explained. The immunization is especially described at two paragraphs dividedly, namely before- and after-exposure vaccination. That the starting time of after-exposure vaccination should be considered carefully in each case in emphasized.

Comparison of various methods of assaying the cytotoxic effects of ethanol on human hepatoblastoma cells (HUH-6 line)

The sensitivity of five kinds of cytotoxicity assays using ethanol on human hepatoblastoma cells (HUH-6 line), which were cultured as monolayers or spheroids, was compared. Ethanol was chosen as a test because it acts on cell membranes directly without being metabolized and exerts its cytotoxicity. The assay methods used were as follows: 3- (4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT), lactate dehydrogenase (LDH), colony formation, cell growth and DNA assays. The sensitivity of the assays was: LDH < DNA < cell growth < MTT < colony formation. LDH assay had the advantage that the same culture could be used for multiple assays, but when a small number of cells were assayed, no significant increase in the release of LDH was detected in the assay cultures compared with the control cultures. Although the DNA and cell growth assays were more sensitive than the LDH assay, the extent of cell damage may be underestimated because the damaged cells and DNA present in the cultures are included in the assay samples. On the other hand, both MTT and colony formation assays showed a high sensitivity. The MTT assay was done within 24 h after ethanol was added to the cultures and was applicable to both monolayer and spheroid cultures, while the colony formation assay required 1-2 weeks and it was applicable only to monolayer cultures. Taken together, the MTT assay was the most suitable method to evaluate the cytotoxic effects of ethanol on HUH-6 cells cultured as either monolayers or spheroids.

Spheroid cultures of human hepatoblastoma cells (HuH-6 line) and their application for cytotoxicity assay of alcohols

Spheroid cultures of human hepatoblastoma cells (HuH-6 line) were established by rotating 3 x 10(6) cells/3 ml culture medium in 25-ml Erlenmeyer flasks on a gyratory shaker. The size of the spheroids rapidly increased until 4 days of culture, and thereafter their size gradually increased until 8 days of culture. A considerable amount of lactate dehydrogenase (LDH) was detected in the culture medium at 24h after seeding because of cell damage by subculturing, but thereafter the amount released was small, indicating that the spheroids were in healthy condition. Albumin production, one of the differentiated functions of hepatocytes, was higher in spheroid cultures than in monolayer cultures. Using this spheroid culture model, the cytotoxic effects of alcohols on HuH-6 cells were studied by measuring the activity of LDH released in the medium from damaged cells. The results indicate that the increasing order of toxicity of the alcohols was as follows: methanol < ethanol < propanol.

Persistence of hepatitis C virus RNA in established human hepatocellular carcinoma cell lines

The persistence of the viral RNA of hepatitis C virus (HCV) was examined in 13 hepatocellular carcinoma (HCC) and two hepatoblastoma cell lines by reverse transcription followed by the polymerase chain reaction (RT-PCR). HCV RNA was detected in three HCC lines (JHH-1, JHH-4, and JHH-6) and negative-strand viral RNA was found in JHH-4, indicating that there is a putative replicative intermediate of HCV in JHH-4 cells. To rule out the possibility of contamination, the partial nucleotide sequences of HCV-specific PCR products of these three cell lines were determined. The clone from JHH-1 belonged to genotype 1 (1a or 1b), and the clones from JHH-4 and JHH-6 belonged to genotype 2b, but their sequences differed from each other. These cell lines may be useful for studies related to HCV.

Establishment and characterization of a human colon cancer cell line, OUMS-23, from a patient with familial adenomatous polyposis

A human colon carcinoma cell line designated OUMS-23 has been established from metastatic pericardial fluid of a male familial adenomatous polyposis patient with colon cancer. Since 1984, the epithelial cells have been maintained in culture. Ultrastructural studies revealed the presence of numerous microvilli on the cell surface and desmosomes between the adjacent cells. The cells secreted carcinoembryonic antigen into the culture medium (15 ng/10(6) cells-1 24 h-1). The cells expressed heat-stable placental-type-like alkaline phosphatase, whereas the normal counterparts expressed tissue-unspecific alkaline phosphatase. Karyotypic analysis showed that the cell line was of human origin and that the chromosome number was broadly distributed between 53 and 118. Southern blot analysis of the APC gene revealed no abnormalities in OUMS-24 cells, while Northern blot analysis demonstrated that the expression of the gene was about one-half that of the normal human fibroblasts. No mutations at the "hot spots" of codons 12 and 61 of H-, K- and N-ras proto-oncogenes were detected in the cells. The cells could grow in soft agar at a cloning efficiency of 6.5%, and upon transplantation into nude mice the cells formed tumors, which were diagnosed as differentiated adenocarcinoma.

[A new liver support system composed of functional human cells and a radial-flow bioreactor]

An artificial liver will be useful for the treatment of acute hepatic failure and a bridge of liver transplantation. The current reports suggest that the hybrid type of artificial liver composed of functional human liver cells and a bioreactor is practical for clinical use. In the present study, we succeeded high density culture on a large-scale of human functional hepatoma (JHH-7) using a newly developed radial flow packed-bed bioreactor. Since the shear stress of this bioreactor is lower than the other type, high density culture without cell damage is possible. JHH-7 cells produced large amounts of human albumin and other liver specific proteins, and then have the function of ammonia metabolism in the system. This study suggests that a radial flow bioreactor will be developed as a new type of artificial liver.

Development of the bovine ileal mucosa

The development of the bovine ileal mucosa was studied with particular reference to maturation during the fetal and neonatal period. In this region, by 4-5 months of fetal development, vacuolation of the epithelial cells had occurred on the villi, and the goblet and absorptive cells in the crypts were present. By 6-9 months, the villi were longer and more numerous than in the previous stages. At the same time, the vacuolated cells could be seen predominantly on the upper half of each villus. The absorptive cells and goblet cells were more distinct in the crypt and lower half of each villus. Moreover, the goblet cells showed differences in mucin, while in the submucosa the lymphoid follicles were seen to have enlarged to become a prominent feature of the Peyer's patches at this stage. At birth, in suckled animals, the ileal cells on the lower area of each villus and in the crypt appeared more like mature cells. In contrast, there were numerous inclusion bodies in epithelial cells on the upper half of each villus. They appeared in the apical portion of the cytoplasm as vacuoles with stainable or dense contents. By 1 week, however, epithelial cells no longer contained inclusion bodies, and absorptive and goblet cell populations had begun to emerge from the crypts. These histological results suggest that the bovine ileal mucosa has two distinct turning points during its development in the fetus and the neonate. Initially all the mucosal structures are present in fetuses at 6-7 months of gestation, and then the vacuolated cells covering the ileal villi are replaced by mature, nonpinocytosing epithelium which emerges from the crypts on or before the 7th day after birth (ileal closure).