Kilohertz alternating current neuromodulation of the pudendal nerves: effects on the anal canal and anal sphincter in rats.

The first two objectives were to establish which stimulation parameters of kilohertz frequency alternating current (KHFAC) neuromodulation influence the effectiveness of pudendal nerve block and its safety. The third aim was to determine whether KHFAC neuromodulation of the pudendal nerve can relax the pelvic musculature, including the anal sphincter. Simulation experiments were conducted to establish which parameters can be adjusted to improve the effectiveness and safety of the nerve block. The outcome measures were block threshold (measure of effectiveness) and block threshold charge per phase (measure of safety). In vivo, the pudendal nerves in 11 male and 2 female anesthetized Sprague Dawley rats were stimulated in the range of 10 Hz to 40 kHz, and the effect on anal pressure was measured. The simulations showed that block threshold and block threshold charge per phase depend on waveform, interphase delay, electrode-to-axon distance, interpolar distance, and electrode array orientation. In vivo, the average anal pressure during unilateral KHFAC stimulation was significantly lower than the average peak anal pressure during low-frequency stimulation (p < 0.001). Stimulation with 20 kHz and 40 kHz (square wave, 10 V amplitude, 50% duty cycle, no interphase delay) induced the largest anal pressure decrease during both unilateral and bilateral stimulation. However, no statistically significant differences were detected between the different frequencies. This study showed that waveform, interphase delay and the alignment of the electrode along the nerve affect the effectiveness and safety of KHFAC stimulation. Additionally, we showed that KHFAC neuromodulation of the pudendal nerves with an electrode array effectively reduces anal pressure in rats.

Endotoxin Translocation and Gut Barrier Dysfunction Are Related to Variceal Bleeding in Patients With Liver Cirrhosis.

Background: Bacterial infections are associated with the risk of variceal bleeding through complex pathophysiologic pathways. Objectives: The primary objective of the present case-control study was to investigate the role of bacterial translocation and intestinal barrier dysfunction in the pathogenesis of variceal bleeding. A secondary objective was to determine independent predictors of key outcomes in variceal bleeding, including bleeding-related mortality. Methods: Eighty-four (n = 84) consecutive patients participated in the study, 41 patients with acute variceal bleeding and 43 patients with stable cirrhosis, and were followed up for 6 weeks. Peripheral blood samples were collected at patient admission and before any therapeutic intervention. Results: Child-Pugh (CP) score (OR: 1.868; p = 0.044), IgM anti-endotoxin antibody levels (OR: 0.954; p = 0.016) and TGF-ß levels (OR: 0.377; p = 0.026) were found to be significant predictors of variceal bleeding. Regression analysis revealed that albumin (OR: 0.0311; p = 0.023), CRP (OR: 3.234; p = 0.034) and FABP2 levels (OR:1.000, p = 0.040), CP score (OR: 2.504; p = 0.016), CP creatinine score (OR: 2.366; p = 0.008), end-stage liver disease model (MELD), Na (OR: 1.283; p = 0.033), portal vein thrombosis (OR: 0.075; p = 0.008), hepatocellular carcinoma (OR: 0.060; p = 0.003) and encephalopathy (OR: 0.179; p = 0.045) were significantly associated with 6-week mortality. Conclusions: Bacterial translocation and gut barrier impairment are directly related to the risk of variceal bleeding. Microbiota-modulating interventions and anti-endotoxin agents may be promising strategies to prevent variceal bleeding.

Shifting gears: Study of immune system parameters of male habitual marathon runners.

Aim: Marathon is a running event in which athletes must cover a distance of 42.195 km. In addition to participating in marathons, marathoners have incorporated extensive running into their lifestyle. In the present study, we investigated the effect of long-term strenuous exercise in the form of marathon running on the immune system. Methods & Results: We collected peripheral blood samples from 37 male marathoners before/after a race and 37 age/sex/body mass index (BMI)-matched healthy sedentary controls. Hematological and biochemical tests revealed race-induced leukocytosis attributable to neutrophilia and significant increases in plasma lactate dehydrogenase (LDH), creatine phosphokinase (CPK), and cortisol concentrations. Phenotypic analysis of lymphocytes revealed race-induced significant decrease in the number of lymphocytes, memory helper T (Th) cells, naive, memory and activated cytotoxic T (Tc) cells, natural killer (NK), NKT, and B1 cells, and a significant increase in the number of activated Th and regulatory Th cells (Tregs). Compared with controls, marathoners maintained significantly lower levels of memory and activated Th cells and higher levels of activated Tc and B1 cells. Measurement of plasma cytokine levels revealed a pro-inflammatory cytokine polarization that increased after the race. Examination of gene expression of cytokines and Th-cell signature transcription factors in peripheral blood mononuclear cells revealed a significant decrease in tumor necrosis factor α (TNF-α) and interleukin (IL)-17, and a significant increase in IL-6, IL-10 and forkhead box P3 (FoxP3) after the race. Compared with controls, marathoners maintained significantly higher levels of TNF-α. Assessment of the suppressive capacity of Tregs in co-cultures of isolated effector Th cells and Tregs showed significantly increased suppressive capacity of marathoners' Tregs after the race. Conclusions: Compared with controls, marathoners live with permanent changes in certain immune parameters. Marathoners exhibit a stable pro-inflammatory cytokine polarization that increases after the race and is counterbalanced by increased numbers of Tregs overexpressing FoxP3 and having increased suppressive capacity.

Androgen receptors in areas of the spinal cord and brainstem: A study in adult male cats.

Sex hormones, including androgens and estrogens, play an important role in autonomic, reproductive and sexual behavior. The areas that are important in these behaviors lie within the spinal cord and brainstem. Relevant dysfunctional behavior in patients with altered androgen availability or androgen receptor sensitivity might be explained by the distribution of androgens and their receptors in the central nervous system. We hypothesize that autonomic dysfunction is correlated with the androgen sensitivity of spinal cord and brainstem areas responsible for autonomic functions. In this study, androgen receptor immunoreactive (AR-IR) nuclei in the spinal cord and brainstem were studied using the androgen receptor antibody PG21 in four uncastrated young adult male cats. A dense distribution of AR-IR nuclei was detected in the superior layers of the dorsal horn, including lamina I. Intensely stained nuclei, but less densely distributed, were found in lamina X and preganglionic sympathetic and parasympathetic cells of the intermediolateral cell column. Areas in the caudal brainstem showing a high density of AR-IR nuclei included the area postrema, the dorsal motor vagus nucleus and the retrotrapezoid nucleus. More cranially, the central linear nucleus in the pons contained a dense distribution of AR-IR nuclei. The mesencephalic periaqueductal gray (PAG) showed a dense distribution of AR-IR nuclei apart from the most central part of the PAG directly adjacent to the ependymal lining. Other areas in the mesencephalon with a dense distribution of AR-IR nuclei were the dorsal raphe nucleus, the retrorubral nucleus, the substantia nigra and the ventral tegmental area of Tsai. It is concluded that AR-IR nuclei are located in specific areas of the central nervous system that are involved in the control of sensory function and autonomic behavior. Furthermore, damage of these AR-IR areas might explain related dysfunction in humans.

Vitamin D-related immunomodulation in patients with liver cirrhosis.

OBJECTIVE(S): Increasing evidence indicates that vitamin D status is linked to severity of liver cirrhosis and patients' survival. However, the potential role of vitamin D-related immunomodulation in hepatic decompensation and patients' mortality in relation to vitamin D deficiency remains unknown. The aim of the current study is to evaluate the association between vitamin D status and vitamin D binding protein (VDBP) levels with serum cytokine and lipopolysaccharide binding protein (LBP) and to examine their role on disease severity and cirrhotics' mortality. METHODS: One hundred consecutive Caucasian patients with liver cirrhosis were enrolled in the study. 25(OH)D, VDBP, and LBP concentrations were assessed by ELISA. Cytokine tumor necrosis factor-a (TNF-a), interleukin 6 (IL-6), IL-1ß, IL-8, IL-10, and IL-12 levels were determined by Cytometric Bead Array. RESULTS: 25(OH)D levels were inversely correlated with CP score, MELD, IL-6, and CP stage and VDBP levels with CP score, MELD, IL-6, IL-8, LBP, and CP stage. Cirrhotics with 25(OH)D deficiency and severe deficiency had significantly higher CP score, increased IL-6 levels and lower VDBP levels. In the multivariate analysis, the independent prognostic factors associated with patients' survival were CP stage B [hazard ratio = 6.75; 95% confidence interval (CI) 1.32, 34.43; P = 0.022], CP stage C (hazard ratio = 7.39; 95% CI 1.41, 38.81; P = 0.018), the presence of hepatocellular carcinoma (hazard ratio = 4.50; 95% CI 1.54, 13.13; P = 0.006) and 25(OH)D levels (hazard ratio = 0.87; 95% CI 0.80, 0.95; P = 0.002). CONCLUSION: The results show that vitamin D status and VDBP levels are associated with liver cirrhosis severity and patients' mortality, possibly through a proinflammatory immune response.

Microenvironment-Dependent Gradient of CTL Exhaustion in the AE17sOVA Murine Mesothelioma Tumor Model.

The immune system, and in particular, cytotoxic CD8+ T cells (CTLs), plays a vital part in the prevention and elimination of tumors. In many patients, however, CTL-mediated tumor killing ultimately fails in the clearance of cancer cells resulting in disease progression, in large part due to the progression of effector CTL into exhausted CTL. While there have been major breakthroughs in the development of CTL-mediated "reinvigoration"-driven immunotherapies such as checkpoint blockade therapy, there remains a need to better understand the drivers behind the development of T cell exhaustion. Our study highlights the unique differences in T cell exhaustion development in tumor-specific CTL which arises over time in a mouse model of mesothelioma. Importantly, we also show that peripheral tumor-specific T cells have a unique expression profile compared to exhausted tumor-infiltrating CTL at a late-stage of tumor progression in mice. Together, these data suggest that greater emphasis should be placed on understanding contributions of individual microenvironments in the development of T cell exhaustion.

Prognostic significance of vitamin D receptor (VDR) gene polymorphisms in liver cirrhosis.

Several polymorphisms in the vitamin D receptor (VDR) are associated with the occurrence of chronic liver disease. Here, we investigated the association between BsmI, ApaI, TaqI and FokI VDR polymorphisms and the severity of liver cirrhosis in relation to serum cytokine and lipopolysaccharide binding protein (LBP) levels and their role on survival in cirrhotic patients. We found that patients harboring the BB genotype had higher MELD score, and they were mainly at CP stage C; patients harboring the AA genotype had increased LBP, IL-1ß and IL-8 levels, and they were mostly at CP stage C; TT genotype carriers had higher MELD score and they were mainly at CP stage C and FF genotype carriers had lower IL-1ß levels when compared to Bb/bb, Aa/aa, Tt/tt and Ff/ff genotypes respectively. In the multivariate analysis ApaI, BsmI and TaqI polymorphisms were independently associated with liver cirrhosis severity. In the survival analysis, the independent prognostic factors were CP score, MELD and the FF genotype. Our results indicate that the ApaI, TaqI and BsmI polymorphisms are associated with the severity of liver cirrhosis, through the immunoregulatory process. Survival is related to the FF genotype of FokI polymorphism, imparting a possible protective role in liver cirrhosis.

Clinical and immunological parameters of Sjögren's syndrome.

Sjögren's syndrome (SS) is a chronic autoimmune disease that primarily affects the exocrine glands, resulting in their functional impairment. In SS, lymphocytic infiltration of salivary and lacrimal glands, and deposition of several types of autoantibodies, mainly anti-SS-A (anti-Ro) and anti-SS-B (anti-La), lead to chronic inflammation, with xerostomia and keratoconjunctivitis sicca. In its primary form (pSS), SS does not involve additional connective tissue diseases, whereas in its secondary and more common form (sSS), SS presents in association with other rheumatic autoimmune diseases, mainly rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and systemic sclerosis (SSc). As in most autoimmune diseases, environmental, hormonal and genetic factors are implicated in SS pathogenesis. In SS T cells predominate in mild lesions, whereas B cells predominate in advanced lesions. Th1, Th2, Th17, follicular helper T (Tfh) cells and regulatory cells (Tregs/Bregs), with their characteristic cytokine profiles, have been implicated in the pathogenesis of SS. It has been suggested that Th1 and Th17 cells initiate SS and, as the disease progresses, Th2 and Tfh cells predominate. It is assumed that, as in all autoimmune and inflammatory conditions, tolerance defects contribute to SS pathogenesis. It is intriguing that in SS it remains unclear which types of regulatory cells are functional and whether they ameliorate or worsen the disease. In this review we present a comprehensive update on SS with emphasis on immune system involvement, and suggest new insights into SS immunopathogenesis.

Bacterial load and cytokine profile in patients with cirrhosis following therapy with proton pump inhibitors: a prospective cohort study.

BACKGROUND: The aim of this study was to explore the presence of bacterial products and the cytokine profile in outpatients with cirrhosis before and after short-term (4-8 weeks) administration of proton pump inhibitors (PPIs). METHODS: Seventeen patients with cirrhosis-male/female: 12/5; age: median 59.2 years (49-65); etiology: HBV±HDV 23.5%, HCV 17.7%, alcohol 41.2%, other 17.6%; Child-Pugh score: median 7.5 (5-12); Model for End-stage Liver Disease: 10.5 (7-21); ascites (%): 3 (17.7)-attending the outpatient clinics were included. None had hepatocellular carcinoma. Indications for PPIs were: esophagitis (n=6, 35.3%), peptic ulcer (n=10, 58.6%) and other (n=1, 5.9%). Bacterial DNA in serum and the levels of endotoxin, lipopolysaccharide binding protein, transforming growth factor-ß, interleukin -1ß, -6, -8, -12, -10, tumor necrosis factor-α and nitric oxide were assessed at baseline (time 1) and at the end of treatment (time 2). The Wilcoxon signed rank test was used to evaluate significant differences in the parameters assayed before and after PPI administration. RESULTS: No patients developed infection during the study period. Bacterial DNA was not detected before or after treatment. No significant differences were observed between the concentrations of any indices between times 1 and 2 (P>0.05). Subgroup analysis according to Child-Pugh stage yielded similar results. CONCLUSION: Short-term administration of PPIs had no effect on bacterial DNA, bacterial products or cytokine concentrations in patients with liver cirrhosis.

The Transcription Factor T-Bet Is Regulated by MicroRNA-155 in Murine Anti-Viral CD8+ T Cells via SHIP-1.

We report here that the expression of the transcription factor T-bet, which is known to be required for effector cytotoxic CD8+ T lymphocytes (CTL) generation and effector memory cell formation, is regulated in CTL by microRNA-155 (miR-155). Importantly, we show that the proliferative effect of miR-155 on CD8+ T cells is mediated by T-bet. T-bet levels in CTL were controlled in vivo by miR-155 via SH2 (Src homology 2)-containing inositol phosphatase-1 (SHIP-1), a known direct target of miR-155, and SHIP-1 directly downregulated T-bet. Our studies reveal an important and unexpected signaling axis between miR-155, T-bet, and SHIP-1 in in vivo CTL responses and suggest an important signaling module that regulates effector CTL immunity.