The pathophysiology of pelvic floor disorders: evidence from a histomorphologic study of the perineum and a mouse model of rectal prolapse

The muscle changes related to pelvic floor disorders are poorly understood. We conducted an anatomical and histological study of the perineum of the normal mouse and of a transgenic mouse strain deficient in urokinase-type plasminogen activator (uPA−/−) that was previously reported to develop a high incidence of rectal prolapse. We could clearly identify the iliococcygeus (ILC) and pubococcygeus (PC) muscles and anal (SPA) and urethral (SPU) sphincters in male and female mice. The bulbocavernosus (BC), ischiocavernosus (ISC) and levator ani (LA) muscles could be found only in male mice. Histochemical analysis of the pelvic floor muscles revealed a majority of type IIA fibres. Rectal prolapses were observed only in male uPA−/− mice. The most obvious finding was an irreducible evagination of the rectal mucosa and a swelling of the entire perineal region corresponding to an irreducible hernia of the seminal vesicles through the pelvic outlet. The hernia caused stretching and thinning of the ISC, BC and LA. Myopathic damage, with degenerated and centronucleated myofibres, were observed in these muscles. The PC, ILC, SPA and SPU were not affected. This study provides an original description of a model of pelvic floor disorder and illustrates the differences existing between the perineum of humans and that of a quadruped species. In spite of these differences, the histopathologic changes observed in the pelvic floor muscles of uPA−/− mice with rectal prolapse suggest that prolonged muscular stretching causes a primary myopathic injury. This should be taken into account in the evaluation of pelvic floor disorders

The expression of Twist has an impact on survival in human bladder cancer and is influenced by the smoking status.

International audienceOBJECTIVES: Twist is considered as transcription factor that regulates epithelial mesenchymal transition (EMT) by at least inhibition of E-cadherin expression. EMT is a key event in the tumor invasion process. The purpose of this study is to investigate the expression of Twist but also those of E- and N-cadherin in human primary bladder tumor and to evaluate its prognostic value. As smoking cigarettes is a strong bladder cancer risk factor, we tried to evaluate the impact of the tobacco status on these molecular abnormalities. MATERIALS AND METHODS: To delineate on the oncogenic role for Twist in human bladder cancer, we evaluated the E- and N-cadherin but also Twist expression (n = 70) by immunohistochemistry. We evaluated the prognostic value of these expressions. Moreover, we tried to correlate these protein expressions to the smoking status of the patients. Overall survival (OS) and progression-free survival (PFS) were evaluated using the Kaplan-Meier method, and multivariate analysis was performed using the Cox proportional hazard analysis. RESULTS: Of the 70 bladder tumors, 28 (40%) cases were positive for Twist expression, 16 (23%) cases were negative for E-cadherin expression, and 12 (17%) were positive for N-cadherin expression. When categorized into negative vs. positive expression, Twist was associated with the stage (P = 0.001), the grade (P < 0.001), the progression (P = 0.02), and the E-cadherin expression (P = 0.01). Moreover, positive Twist expression clearly predicted poorer PFS (P = 0.02). In the multivariate analysis, both positive Twist expression and loss of E-cadherin expression were independent prognostic factors for PFS (P = 0.046 and P = 0.001, respectively) and only loss of E-cadherin expression for the OS (P < 0.001). We also demonstrated that almost 60% (16/28) of patients with Twist-positive expression were current smokers at the time of the diagnosis, corroborating the fact that smoking modulates the expression of EMT markers including Twist. CONCLUSION: Positive Twist expression may be a useful prognostic marker for patients with bladder cancer. Its expression seems to be correlated to the tobacco status of the patients

Molecular grading of urothelial cell carcinoma with fibroblast growth factor receptor 3 and MIB-1 is superior to pathologic grade for the prediction of clinical outcome

Purpose: Fibroblast growth factor receptor 3 (FGFR3) mutations were recently found at a high frequency in well-differentiated urothelial cell carcinoma (UCC). We investigated the relationship between FGFR3 status and three molecular markers (MIB-1, P53, and P27kip1) associated with worse prognosis and determined the reproducibility of pathologic grade and molecular variables. Patients and Methods: In this multicenter study, we included 286 patients with primary (first diagnosis) UCC. The histologic slides were reviewed. FGFR3 status was examined by polymerase chain reaction-single strand conformation polymorphism and sequencing. Expression levels of MIB-1, P53, and P27kip1 were determined by immunohistochemistry. Mean follow-up was 5.5 years (range, 0.4 to 18.4 years). Results: FGFR3 mutations were detected in 172 (60%) of 286 UCCs. Grade 1 tumors had an FGFR3 mutation in 88% of patient samples and grade 3 tumors in 16% of patient samples. Conversely, aberrant expression patterns of MIB-1, P53, and P27kip1 were seen in 5%, 2%, and 3% of grade 1 tumors and in 85%, 60%, and 56% of grade 3 tumors, respectively. In multivariate analysis with recurrence rate, progression, and disease-specific survival as end points, the combination of FGFR3 and MIB-1 proved independently significant in all three cases. By using these two molecular markers, three molecular grades (mGs) could be identified: mG1 (mutation; normal expression), favorable prognosis; mG2 (two remaining combinations), intermediate prognosis; and mG3 (no mutation; high expression), poor prognosis. The molecular variables were more reproducible than pathologic grade (85% to 100% v 47% to 61%). Conclusion: The FGFR3 mutation represents the favorable molecular pathway of UCC. Molecular grading provides a new, simple, and highly reproducible tool for clinical decision making in UCC patients

Respiratory support in patients with severe COVID-19 in the International Severe Acute Respiratory and Emerging Infection (ISARIC) COVID-19 study: a prospective, multinational, observational study

Background: Up to 30% of hospitalised patients with COVID-19 require advanced respiratory support, including high-flow nasal cannulas (HFNC), non-invasive mechanical ventilation (NIV), or invasive mechanical ventilation (IMV). We aimed to describe the clinical characteristics, outcomes and risk factors for failing non-invasive respiratory support in patients treated with severe COVID-19 during the first two years of the pandemic in high-income countries (HICs) and low middle-income countries (LMICs). Methods: This is a multinational, multicentre, prospective cohort study embedded in the ISARIC-WHO COVID-19 Clinical Characterisation Protocol. Patients with laboratory-confirmed SARS-CoV-2 infection who required hospital admission were recruited prospectively. Patients treated with HFNC, NIV, or IMV within the first 24 h of hospital admission were included in this study. Descriptive statistics, random forest, and logistic regression analyses were used to describe clinical characteristics and compare clinical outcomes among patients treated with the different types of advanced respiratory support. Results: A total of 66,565 patients were included in this study. Overall, 82.6% of patients were treated in HIC, and 40.6% were admitted to the hospital during the first pandemic wave. During the first 24 h after hospital admission, patients in HICs were more frequently treated with HFNC (48.0%), followed by NIV (38.6%) and IMV (13.4%). In contrast, patients admitted in lower- and middle-income countries (LMICs) were less frequently treated with HFNC (16.1%) and the majority received IMV (59.1%). The failure rate of non-invasive respiratory support (i.e. HFNC or NIV) was 15.5%, of which 71.2% were from HIC and 28.8% from LMIC. The variables most strongly associated with non-invasive ventilation failure, defined as progression to IMV, were high leukocyte counts at hospital admission (OR [95%CI]; 5.86 [4.83–7.10]), treatment in an LMIC (OR [95%CI]; 2.04 [1.97–2.11]), and tachypnoea at hospital admission (OR [95%CI]; 1.16 [1.14–1.18]). Patients who failed HFNC/NIV had a higher 28-day fatality ratio (OR [95%CI]; 1.27 [1.25–1.30]). Conclusions: In the present international cohort, the most frequently used advanced respiratory support was the HFNC. However, IMV was used more often in LMIC. Higher leucocyte count, tachypnoea, and treatment in LMIC were risk factors for HFNC/NIV failure. HFNC/NIV failure was related to worse clinical outcomes, such as 28-day mortality. Trial registration This is a prospective observational study; therefore, no health care interventions were applied to participants, and trial registration is not applicable