What is associated with painful polyneuropathy? A cross-sectional analysis of symptoms and signs in patients with painful and painless polyneuropathy.

ABSTRACT: It is still unclear how and why some patients develop painful and others painless polyneuropathy. The aim of this study was to identify multiple factors associated with painful polyneuropathies (NeuP). A total of 1181 patients of the multicenter DOLORISK database with painful (probable or definite NeuP) or painless (unlikely NeuP) probable or confirmed neuropathy were investigated clinically, with questionnaires and quantitative sensory testing. Multivariate logistic regression including all variables (demographics, medical history, psychological symptoms, personality items, pain-related worrying, life-style factors, as well as results from clinical examination and quantitative sensory testing) and machine learning was used for the identification of predictors and final risk prediction of painful neuropathy. Multivariate logistic regression demonstrated that severity and idiopathic etiology of neuropathy, presence of chronic pain in family, Patient-Reported Outcomes Measurement Information System Fatigue and Depression T-Score, as well as Pain Catastrophizing Scale total score are the most important features associated with the presence of pain in neuropathy. Machine learning (random forest) identified the same variables. Multivariate logistic regression archived an accuracy above 78%, random forest of 76%; thus, almost 4 out of 5 subjects can be classified correctly. This multicenter analysis shows that pain-related worrying, emotional well-being, and clinical phenotype are factors associated with painful (vs painless) neuropathy. Results may help in the future to identify patients at risk of developing painful neuropathy and identify consequences of pain in longitudinal studies.

Digital Examination vs. 4D Transperineal Ultrasound-Do They Compare in Labour Management? A Pilot Study.

The aim was to compare transperineal ultrasound (TPU) with parameters of the Bishop Score during the first stage of labour and evaluate how TPU can contribute towards improving labour management. Digital examination (DE) and TPU were performed on 42 women presenting at the labour ward with regular contractions. TPU measurements included the head-symphysis distance, angle of progression, diameter of the cervical wall, cervical dilation (CD) and cervical length (CL). To examine if TPU can monitor labour progress, correlations of TPU parameters were calculated. Agreement of DE and TPU was examined for CL and CD measurements and for two groups divided into latent (CD < 5 cm) and active stages of labour (CD ≥ 5 cm). TPU parameters indicated a moderate negative correlation of CD and CL (Pearson: r = -0.667; Spearman = -0.611). The other parameters showed a weak to moderate correlation. DE and TPU measurements for CD showed better agreement during the latent stage than during the active stage. The results of the present study add to the growing evidence that TPU may contribute towards an improved labour management, suggesting a combined approach of TPU and DE to monitor the latent first stage of labour and using only DE during the active stage of labour.

CIN2 + detection in high-risk HPV patients with no or minor cervical cytologic abnormalities: a clinical approach validated by machine learning.

PURPOSE: To evaluate the feasibility and diagnostic value of the combination of colposcopy, cytology and hrHPV (high-risk human papilloma virus) PCR (polymerase chain reaction) testing in patients with no or minor cytologic abnormalities and HPV high risk infection and to find the best predictors for the presence of CIN2 + in this patient collective. METHODS: Three hundred and thirty-four hrHPV patients with normal cytology or minor cytologic abnormalities who had a colposcopic examination at the center of colposcopy at the university hospital Aachen in 2021 were enrolled in this retrospective cohort analysis. Multivariate logistic regression and a machine-learning technique (random forests, leave-one-out analysis) were used. RESULTS: The overall risk for CIN2 + in hrHPV-positive patients with normal cytology was 7.7% (N = 18) (5% for CIN3 +), 18% (N = 16) (10.1% for CIN3 +) in patients with PAP IIp (ASC-US) and 62.5% (N = 5) (25% for CIN3 +) in patients with PAP IIg (AGC). Variables that show a statistically significant influence for the CIN-status are 'major change' as the result of colposcopy, transformation zone type T1, PAP IIg upon referral (AGC) and hrHPV category 1a (HPV 16/18) detection. Using machine learning (random forests) techniques, the main influencing variables were confirmed. A monotonously decreasing risk for CIN2 + from hrHPV category 1a to 3 (in accordance to the IACR guidelines) was found. CONCLUSION: In the collective of hrHPV patients with no or minor cytologic abnormalities, the result of colposcopy and HPV PCR status are key predictors for the detection of CIN2 + with a monotonously decreasing risk for CIN2 + from hrHPV category 1a to 3.

Reliability and Reproducibility of Analyzing 3D Transperineal Ultrasound Volumes Obtained in the First Phase of Labor - A Pilot Study.

PURPOSE: The aim of this study was to investigate the reliability and reproducibility of transperineal ultrasound (TPUS) in the initial phase of labor. As TPUS is a common method, it could supplement vaginal palpation and even replace it in certain situations. In addition, we used a 4-dimensional method for the assessment of cervical effacement. MATERIALS AND METHODS: 54 women in labor were included and underwent TPUS. The resulting images from the acquired 4D volumes were evaluated after the examination for the first time and a second time after 21 days. The measured values were cervical length, dilatation and effacement, the angle of progression (AoP), and head-perineum distance. RESULTS: 54 patients were examined. TPUS images were unable to be evaluated in 12 patients because of cervical dilatation of more than 5 cm or poor image quality. Thus, 42 measurements were included. The concordance correlation coefficients according to Lin are satisfactory overall, with one exception for cervical effacement. The accuracy component of cervical length (CCCLin: 0.93; accuracy: 1.00), dilatation (CCCLin: 0.93; accuracy: 1.00), and AoP (CCCLin: 0.87; accuracy: 1.00) is excellent and still high for the head-perineum distance (CCCLin: 0.89; accuracy: 0.96) and cervical effacement (CCCLin: 0.77; accuracy: 0.97). CONCLUSION: TPUS is a valuable noninvasive tool with good diagnostic accuracy for the AoP, cervical length, and dilatation. Our study provides support for the use of TPUS to complement a vaginal examination. It should not replace a digital examination but should serve as a suitable alternative method for monitoring labor progression in the future.

HPV High-risk Multiple Infection Is a Key Predictor of Cervical Dysplasia in Diagnostic LEEPs: a Retrospective Cohort Analysis.

Objective This study aimed to identify predictors for the presence of cervical dysplasia in diagnostic LEEPs (Loop Electrical Excision Procedure) of the cervix. Materials/Methods The study was designed as a retrospective single-institution cohort analysis of all patients who underwent LEEP without prior proof of high-grade intraepithelial lesion (diagnostic LEEP) between 2015 and 2020 in the Department of Obstetrics and Gynecology of University Hospital Aachen. In order to identify the most meaningful predictive variables for CIN status (CIN2+ or non-CIN2+), multivariate logistic regression was performed and a machine-learning method was used. Results A total of 849 patients with an indication for loop excision of the cervix were assessed for eligibility. Finally, 125 patients without prior proof of CIN2+ were included into the study. Based on the final multivariate logistic regression model, multiple high-risk HPV infections (p = 0.001), the presence of a T2 transformation zone (p = 0.003) and major lesion changes (p = 0.015) as a result of the colposcopy examination were found to be statistically significant for CIN status based on the diagnostic LEEP. Subsequent ROC analysis showed a high predictive value for the model of 88.35% (AUC). The machine-learning technique (recursive partitioning) identified similar variables as important for CIN status with an accuracy of 75%. Conclusion For clinical decision-making, the result of the colposcopy examination (T2, major change) as well as the results of HPV testing (multiple high-risk HPV infections) are stronger indicators for clinicians to perform diagnostic excisional procedures of the cervix than the presence of high-grade cytological abnormalities.

Evaluation of urinary continence status and its influence on quality of life after gyneco-oncological treatment of female pelvic malignancies at an oncological center.

Urinary incontinence (UI) could negatively affect a person's quality of life (QoL). This study investigates the association among gynecological cancers, their treatments, UI, and its effect on the QoL of survivors of gynecological cancer. This cross-sectional questionnaire-based study included 121 cases from 405 patients who had undergone gyneco-oncological therapy. The participants were asked whether they experienced any form of UI and whether it impacted their QoL. The following therapies were used to treat the 12 gynecologic tumor types found in the participants: surgery (n = 116, 95.87%), chemotherapy (CTx) (n = 51, 42.2%), radiotherapy (RTx) (n = 31, 25.6%), and antibody therapy (ABT) (n = 11, 9.1%). No significant association was determined between tumor type and UI. However, body mass index (BMI), radical hysterectomy, vulvar or vaginal surgery, and presence of UI before treatment had significant impacts on the presence of UI. The surgical access routes, CTx, ABT, and hysterectomy had significant impacts on the severity of UI after treatment. Among all patients, 55.4% reported very good QoL. These reports of good QoL by patients could be due to their very good adjustment to the situation, with regard to being diagnosed with and receiving treatment for cancer, or due to the patients considering UI to not be much of an issue. Additionally, 34% of patients reported they had not been informed about the risk of UI before treatment. Informing patients about UI as one of the risks of therapy before initiating the treatment is crucial as patients who had been informed beforehand coped with UI far better than those who were not informed. Hence, the treatment of UI is often successful, so patients should be encouraged to receive urogynecological consultation.

Obstetric anal sphincter injuries (OASIS): using transperineal ultrasound (TPUS) for detecting, visualizing and monitoring the healing process.

PURPOSE: The aim of this study was to examine whether OASIS, and its extent, can be confirmed or excluded using transperineal ultrasound (TPUS). A further objective of this study was to monitor the healing process over a period of 6 months and to establish a connection between the sonographic appearance of obstetric anal sphincter injury (OASIS) and anal incontinence. MATERIALS AND METHODS: In this retrospective clinical study, women with OASIS who gave birth between March 2014 and August 2019 were enrolled. All the patients underwent TPUS 3 days and 6 months after delivery. A GE E8 Voluson ultrasound system with a 3.5-5 MHz ultrasound probe was used. The ultrasound images showed a third-degree injury, with the measurement of the width of the tear and its extent (superficial, partial, complete, EAS and IAS involvement). A positive contraction effect, a sign of sufficient contraction, was documented. Six months after delivery, a sonographic assessment of the healing (healed, scar or still fully present) was performed. A Wexner score was obtained from each patient. The patients' medical histories, including age, parity, episiotomy and child's weight, were added. RESULTS: Thirty-one of the 55 recruited patients were included in the statistical evaluation. Three patients were excluded from the statistical evaluation because OASIS was excluded on TPUS 3 days after delivery. One patient underwent revision surgery for anal incontinence and an inadequately repaired anal sphincter injury, as shown sonographic assessment, 9 days after delivery. Twenty patients were excluded for other reasons. The results suggest that a tear that appears smaller (in mm) after 3 days implies better healing after 6 months. This effect was statistically significant, with a significance level of alpha = 5% (p = 0.0328). Regarding anal incontinence, women who received an episiotomy had fewer anal incontinence symptoms after 6 months. The effect of episiotomy was statistically significant, with a significance level of alpha = 5% (p = 0.0367). CONCLUSION: TPUS is an accessible, non-invasive method for detecting, quantifying, following-up and monitoring OASIS in patients with third-degree perineal tears. The width, as obtained by sonography, is important with regard to the healing of OASIS. A mediolateral episiotomy seems to prevent anal incontinence after 6 months.

Development of a bedside tool-kit for assessing sensitization in patients with chronic osteoarthritis knee pain or chronic knee pain after total knee replacement.

ABSTRACT: Different pathophysiological mechanisms contribute to the pain development in osteoarthritis (OA). Sensitization mechanisms play an important role in the amplification and chronification of pain and may predict the therapeutic outcome. Stratification of patients according to their pain mechanisms could help to target pain therapy. This study aimed at developing an easy-to-use, bedside tool-kit to assess sensitization in patients with chronic painful knee OA or chronic pain after total knee replacement (TKR). In total, 100 patients were examined at the most affected knee and extrasegmentally by the use of 4 standardized quantitative sensory testing parameters reflecting sensitization (mechanical pain threshold, mechanical pain sensitivity, dynamic mechanical allodynia, and pressure pain threshold), a bedside testing battery of equivalent parameters including also temporal summation and conditioned pain modulation, and pain questionnaires. Machine learning techniques were applied to identify an appropriate set of bedside screening tools. Approximately half of the patients showed signs of sensitization (46%). Based on machine learning techniques, a composition of tests consisting of 3 modalities was developed. The most adequate bedside tools to detect sensitization were pressure pain sensitivity (pain intensity at 4 mL pressure using a 10-mL blunted syringe), mechanical pinprick pain sensitivity (pain intensity of a 0.7 mm nylon filament) over the most affected knee, and extrasegmental pressure pain sensitivity (pain threshold). This pilot study presents a first attempt to develop an easy-to-use bedside test to probe sensitization in patients with chronic OA knee pain or chronic pain after TKR. This tool may be used to optimize individualized, mechanism-based pain therapy.

Methodological Aspects in Studies Based on Clinical Routine Data.

Randomized controlled clinical trials are regarded as the gold standard for comparing different clinical interventions, but generally their conduct is operationally cumbersome, time-consuming, and expensive. Studies and investigations based on clinical routine data on the contrary utilize existing data acquired under real-life conditions and are increasingly popular among practitioners. In this paper, methodological aspects of studies based on clinical routine data are discussed. Important limitations and considerations as well as unique strengths of these types of studies are indicated and exemplarily demonstrated in a recent real-case study based on clinical routine data. In addition two simulation studies reveal the impact of bias in studies based on clinical routine data on the type I error rate and false decision rate in favor of the inferior intervention. It is concluded that correctly analyzing clinical routine data yields a valuable addition to clinical research; however, as a result of a lack of statistical foundation, internal validity, and comparability, generalizing results and inferring properties derived from clinical routine data to all patients of interest has to be considered with extreme caution. FUNDING: Grünenthal GmbH.

Anatomy meets dentistry! Linking anatomy and clinical practice in the preclinical dental curriculum.

BACKGROUND: Establishing a strong link early on between preclinical coursework and the clinical context is necessary for students to be able to recognize the practical relevance of the curriculum during their preclinical anatomical courses and to transfer knowledge more easily. Our objective was to enhance the clinical relevance of a preclinical anatomy course for second-year medical students of dentistry by implementing an interdisciplinary skills training course on "Palpation of the Head and Neck Muscles" and to measure the learning outcomes. METHODS: For the curricular development of the expanded course module, Kern's 6-step approach was applied including subjective evaluation. We used a peer-teaching format supported by an e-learning application. A randomized control study measured effects of the two components (skills training, e-module) on learning outcomes. Four learning methods were compared: (1) lecture, (2) lecture + e-module, (3) lecture + skills training, (4) lecture + skills training + e-module. An objective structured clinical examination (OSCE) was used to measure and compare learning outcomes. RESULTS: The two-way variance analysis demonstrated that participation in the skills training had a statistically significant effect on the OSCE results (p = 0.0007). Students who participated in the skills training did better (φ 107.4 ± 14.4 points) than students who only attended the lecture (φ 88.8 ± 26.2 points). Students who used the e-module but did not attend the skills training earned a slightly but not significantly higher average number of points (φ 91.8 ± 31.3 points) than those who only attended the lecture. The learning outcomes of the skills training were again significantly increased when the training was combined with the e-module (φ 121.8 ± 21.8 points), thus making it the ideal method for achieving the learning objectives defined in this study. CONCLUSIONS: The "Palpation of the Head and Neck Muscles" interdisciplinary skills training course linking basic anatomical knowledge and clinical skills led to clearly improved learning outcomes for both, anatomical knowledge and clinical skills. The additional use of an e-learning tool (e-module) improved the learning effect.

Comparison of Perineal Sonographically Measured and Functional Urodynamic Urethral Length in Female Urinary Incontinence.

Objectives. To detect the anatomical insufficiency of the urethra and to propose perineal ultrasound as a useful, noninvasive tool for the evaluation of incontinence, we compared the anatomical length of the urethra with the urodynamic functional urethral length. We also compared the urethral length between continent and incontinent females. Methods. 149 female patients were enrolled and divided into four groups (stress, urge, or mixed incontinence; control). Sonographically measured urethral length (SUL) and urodynamic functional urethral length (FUL) were analyzed statistically. Standardized and internationally validated incontinence questionnaire ICIQ-SF results were compared between each patient group. Results. Perineal SUL was significantly longer in incontinent compared to continent patients (p < 0.0001). Pairwise comparison of each incontinent type (stress, urge, or mixed incontinence) with the control group showed also a significant difference (p < 0.05). FUL was significantly shorter in incontinent patients than in the control group (p = 0.0112). But pairwise comparison showed only a significant difference for the stress incontinence group compared with the control group (p = 0.0084) and not for the urge or mixed incontinent group. No clear correlation between SUL, FUL, and ICIQ-SF score was found. Conclusions. SUL measured by noninvasive perineal ultrasound is a suitable parameter in the assessment of female incontinence, since incontinent women show a significantly elongated urethra as a sign of tissue insufficiency, independent of the type of incontinence.

Tolerability, Safety, and Quality of Life with Tapentadol Prolonged Release (PR) Compared with Oxycodone/Naloxone PR in Patients with Severe Chronic Low Back Pain with a Neuropathic Component: A Randomized, Controlled, Open-label, Phase 3b/4 Trial.

OBJECTIVE: To evaluate tolerability, safety, and quality-of-life outcomes in non-opioid-pretreated patients with severe chronic low back pain with a neuropathic component receiving tapentadol PR vs. oxycodone/naloxone PR. METHODS: Eligible patients (average pain intensity [numerical rating scale] ≥ 6; painDETECT positive/unclear ratings) were randomized to twice-daily tapentadol PR 50 mg or oxycodone/naloxone PR 10 mg/5 mg. After a 21-day titration (maximum twice-daily doses: tapentadol PR 250 mg, or oxycodone/naloxone PR 40 mg/20 mg plus oxycodone PR 10 mg), target doses were continued for 9 weeks. Change in the Patient Assessment of Constipation Symptoms (PAC-SYM) total score from baseline to final evaluation was a primary endpoint. RESULTS: For the primary tolerability-related endpoint, the 97.5% exact repeated confidence interval for tapentadol PR minus oxycodone/naloxone PR for the PAC-SYM total score was [-0.259, 0.121], showing noninferiority (upper limit < 0.7). Incidences of constipation and vomiting were significantly lower with tapentadol PR than oxycodone/naloxone PR (P ≤ 0.045). Confirmatory superiority based on formal noninferiority was shown for the primary effectiveness endpoint (change from baseline to final evaluation in pain intensity) for tapentadol PR vs. oxycodone/naloxone PR (presented separately). Improvements in the Short Form-12 physical component summary and EuroQol-5 Dimension health status index and health state assessment were significantly greater with tapentadol PR vs. oxycodone/naloxone PR (P ≤ 0.024). CONCLUSIONS: Tapentadol PR had a minimal impact on bowel function (noninferior to oxycodone/naloxone PR) and, along with superior effectiveness (presented separately), was associated with significantly lower incidences of constipation and vomiting and significant improvements in quality-of-life measures vs. oxycodone/naloxone PR.

Sextant-Specific Analysis of Detection and Tumor Volume by HistoScanning™.

INTRODUCTION: Published results of HistoScanning™ (HS) for prostate cancer (PCa) diagnostics are inconsistent and their value remains unclear. We prospectively analyzed the detection rate and tumor volume concordance in PCa patients. MATERIAL AND METHODS: Two hundred and eighty-two patients with biopsy-proven PCa scheduled for radical prostatectomy (RP) were included. All patients underwent ultrasonographical examination by HS prior to surgery. HS was evaluated compared to RP specimen as to (1) the prediction of overall tumor volume and (2) accuracy of HS in detection of PCa lesions larger than 0.2/0.5 ml, separated for each sextant. For each sextant, receiver operating characteristic (ROC)-analysis and area under the curve were determined. Sensitivity and specificity were calculated and visualized in ROC-curves. RESULTS: HS tends to underestimate volume of cancerous lesions, particularly larger lesions >8 ml. Using a 0.2 ml detection threshold, specificity and sensitivity of HS were between 29-68% and 46-78%. For a 0.5 ml detection threshold, sextant-specific specificity increased to 59-92% and sensitivity decreased to 16-54%. Stratification according to pre-operational PSA values did not improve performance characteristics of HS. CONCLUSIONS: Our results do not support a significant contribution of HS to PCa diagnostics.

Vitamin K antagonism aggravates chronic kidney disease-induced neointimal hyperplasia and calcification in arterialized veins: role of vitamin K treatment?

Arteriovenous fistula (AVF) is the common vascular access type for a hemodialysis patient. Its failure is due to neointimal hyperplasia. Vitamin K antagonists are given to lower thrombosis tendency, but have side effects that enhance arterial calcifications. Here, we investigated the effects of vitamin K antagonists and vitamin K2 (K2) treatment on neointimal hyperplasia development and calcification in rats and in arterialized human veins. AVF was generated in female rats while chronic kidney disease (CKD) was induced using an adenine-enriched diet. Arterialization, CKD, and vitamin K antagonists all significantly enhanced venous neointimal hyperplasia. K2 treatment, additional to vitamin K antagonists, significantly reduced neointimal hyperplasia in arterialized veins in healthy rats but not in rats with CKD. Arterialization, CKD, and vitamin K antagonism all significantly increased, whereas K2 supplementation attenuated calcification in healthy rats and rats with CKD. K2 significantly enhanced matrix Gla protein carboxylation in control rats and rats with CKD. Arterialized human vein samples contained inactive matrix Gla protein at calcification and neointimal hyperplasia sites, indicating local vitamin K deficiency. Thus, vitamin K antagonists have detrimental effects on AVF remodeling, whereas K2 reduced neointimal hyperplasia and calcification indicating vasoprotective effects. Hence, K2 administration may be useful to prevent neointimal hyperplasia and calcification in arterialized veins

Effectiveness of Tapentadol Prolonged Release (PR) Compared with Oxycodone/Naloxone PR for the Management of Severe Chronic Low Back Pain with a Neuropathic Component: A Randomized, Controlled, Open-Label, Phase 3b/4 Study.

OBJECTIVE: To evaluate the effectiveness of tapentadol prolonged release (PR) vs. oxycodone/naloxone PR in non-opioid-pretreated patients with severe chronic low back pain with a neuropathic pain component. METHODS: Eligible patients (average pain intensity [numerical rating scale-3 (NRS-3)] ≥6; painDETECT positive/unclear) were randomized to twice-daily tapentadol PR 50 mg or oxycodone/naloxone PR 10 mg/5 mg. After a 21-day titration (maximum twice-daily doses: tapentadol PR 250 mg, or oxycodone/naloxone PR 40 mg/20 mg plus oxycodone PR 10 mg), target doses were continued for 9 weeks. The primary effectiveness endpoint was the change in NRS-3 from baseline to final evaluation; the exact repeated confidence interval (RCI) for tapentadol PR minus oxycodone/naloxone PR was used to establish noninferiority (upper limit <1.3) and superiority (confirmatory analyses). RESULTS: For the primary effectiveness endpoint, tapentadol PR was noninferior to oxycodone/naloxone PR (97.5% RCI: [-1.820, -0.184]; P < 0.001). This exact RCI also yielded evidence of superiority for tapentadol PR vs. oxycodone/naloxone PR (significantly greater reduction in pain intensity; P = 0.003). Improvements (baseline to final evaluation) in painDETECT and Neuropathic Pain Symptom Inventory scores were significantly greater with tapentadol PR vs. oxycodone/naloxone PR (all P ≤ 0.005). CONCLUSIONS: The study was formally shown to be positive and demonstrated, in the primary effectiveness endpoint, the noninferiority for tapentadol PR vs. oxycodone/naloxone PR. The effectiveness of tapentadol PR was superior to that of oxycodone/naloxone PR by means of clinical relevance and statistical significance (confirmatory evidence of superiority). Tapentadol PR was associated with significantly greater improvements in neuropathic pain-related symptoms and global health status than oxycodone/naloxone PR and with a significantly better gastrointestinal tolerability profile. Tapentadol PR may be considered a first-line option for managing severe chronic low back pain with a neuropathic pain component.

Inference for blocked randomization under a selection bias model.

We provide an asymptotic test to analyze randomized clinical trials that may be subject to selection bias. For normally distributed responses, and under permuted block randomization, we derive a likelihood ratio test of the treatment effect under a selection bias model. A likelihood ratio test of the presence of selection bias arises from the same formulation. We prove that the test is asymptotically chi-square on one degree of freedom. These results correlate well with the likelihood ratio test of Ivanova et al. (2005, Statistics in Medicine 24, 1537-1546) for binary responses, for which they established by simulation that the asymptotic distribution is chi-square. Simulations also show that the test is robust to departures from normality and under another randomization procedure. We illustrate the test by reanalyzing a clinical trial on retinal detachment.

Intestinal genetic inactivation of caspase-8 diminishes migration of enterocytes.

AIM: To verify the hypothesis that caspase-8 (Casp8), which regulates cellular apoptosis and necroptosis, is critically involved in enterocyte migration. METHODS: Casp8-silenced Caco2 cells were used in migration assays. In addition, enterocyte-specific Casp8 heterozygous (Casp8(+/∆int)) or homozygous knockout mice (Casp8(∆int)) were generated by crossing genetically modified mice carrying loxP recombination sites in intron 2 and 4 of the murine Casp8 gene with transgenic animals expressing a cre-transgene under control of the villin promoter in a pure C57/BL6 genetic background. The nucleoside analog BrdU was injected i.p. in male Casp8(+/∆int) and Casp8(∆int) animals 4 h, 20 h, or 40 h before performing morphometric studies. Locations of anti-BrdU-immunostained cells (cell(max)) in at least 50 hemi-crypts of 6 histoanatomically distinct intestinal mucosal regions were numbered and extracted for statistical procedures. For the mice cohort (n = 28), the walking distance of enterocytes was evaluated from cell(max) within crypt (n = 57), plateau (n = 19), and villus (n = 172) positions, resulting in a total of 6838 observations. Data analysis was performed by fitting a three-level mixed effects model to the data. RESULTS: In cell culture experiments with Caco2 cells, Casp8 knockdown efficiency mediated by RNA interference on Casp8 transcripts was 80% controlled as determined by Western blotting. In the scratch assay, migration of Casp8-deleted Caco2 cells was significantly diminished when compared with controls (Casp8(∆scramble) and Caco2). In BrdU-labeled Casp8(∆int) mice, cell(max) locations were found along the hemi-crypts in a lower position than it was for Casp8(+/∆int) or control (cre-negative) animals. Statistical data analysis with a three-level mixed effects model revealed that in the six different intestinal locations (distinct segments of the small and large intestine), cell movement between the three mice groups differed widely. Especially in duodenal hemi-crypts, enterocyte movement was different between the groups. At 20 h, duodenal cell(max) location was significantly lower in Casp8(∆int) (25.67 ± 2.49) than in Casp8(+/∆int) (35.67 ± 4.78; P < 0.05) or control littermates (44.33 ± 0.94; P < 0.01). CONCLUSION: Casp8-dependent migration of enterocytes is likely involved in intestinal physiology and inflammation-related pathophysiology.

Microcirculatory perfusion shift in the gut wall layers induced by extracorporeal circulation.

OBJECTIVE: Extracorporeal circulation (ECC) is regularly applied to maintain organ perfusion during major aortic and cardiovascular surgery. During thoracoabdominal aortic repair, ECC-driven selective visceral arterial perfusion (SVP) results in changed microcirculatory perfusion (shift from the muscularis toward the mucosal small intestinal layer) in conjunction with macrohemodynamic hypoperfusion. The underlying mechanism, however, is unclear. Therefore, the aim of this study was to assess in a porcine model whether ECC itself or the hypoperfusion induced by SVP is responsible for the mucosal/muscular shift in the small intestinal wall. METHODS: A thoracoabdominal aortic approach was performed in 15 healthy pigs divided equally into three groups: group I, control; group II, thoracic aortic cross-clamping with distal aortic perfusion; and group III, thoracic aortic cross-clamping with distal aortic perfusion and SVP. Macrocirculatory and microcirculatory blood flow was assessed by transit time ultrasound volume flow measurement and fluorescent microspheres. In addition, markers for metabolism and intestinal ischemia-reperfusion injury were determined. RESULTS: ECC with a roller pump induced a significant switch from the muscularis and mucosal layer of the small intestine, even with adequate macrocirculation (mucosal/muscular perfusion ratio: group I vs II, P = .005; group I vs III, P = .0018). Furthermore, the oxygen extraction ratio increased significantly in groups II (>30%) and III (>40%) in the beginning of the ECC compared with the control (group I vs II, P = .0037; group I vs III, P = .0062). Lactate concentrations and pH values did not differ between groups I and II; but group III demonstrated a significant shifting toward a lactate-associated acidosis (lactate: group I vs III, P = .0031; pH: group I vs III, P = .0001). CONCLUSIONS: We demonstrated a significant shifting between the small intestinal gut wall layers induced by roller pump-driven ECC. The shift occurs independently of macrohemodynamics, with a significant effect on aerobic metabolism in the gut wall. Consequently, an optimal intestinal perfusion cannot be guaranteed by a roller pump; therefore, perfusion techniques need to be optimized.