Ben M. Stutchfield

Relaxin modulates human and rat hepatic myofibroblast function and ameliorates portal hypertension in vivo.

Active myofibroblast (MF) contraction contributes significantly to the increased intrahepatic vascular resistance that is the primary cause of portal hypertension (PHT) in cirrhosis. We sought proof of concept for direct therapeutic targeting of the dynamic component of PHT and markers of MF activation using short‐term administration of the peptide hormone relaxin (RLN). We defined the portal hypotensive effect in rat models of sinusoidal PHT and the expression, activity, and function of the RLN‐receptor signaling axis in human liver MFs. The effects of RLN were studied after 8 and 16 weeks carbon tetrachloride intoxication, following bile duct ligation, and in tissue culture models. Hemodynamic changes were analyzed by direct cannulation, perivascular flowprobe, indocyanine green imaging, and functional magnetic resonance imaging. Serum and hepatic nitric oxide (NO) levels were determined by immunoassay. Hepatic inflammation was assessed by histology and serum markers and fibrosis by collagen proportionate area. Gene expression was analyzed by quantitative reverse‐transcription polymerase chain reaction (qRT‐PCR) and western blotting and hepatic stellate cell (HSC)‐MF contractility by gel contraction assay. Increased expression of RLN receptor (RXFP1) was shown in HSC‐MFs and fibrotic liver diseases in both rats and humans. RLN induced a selective and significant reduction in portal pressure in pathologically distinct PHT models, through augmentation of intrahepatic NO signaling and a dramatic reduction in contractile filament expression in HSC‐MFs. Critical for translation, RLN did not induce systemic hypotension even in advanced cirrhosis models. Portal blood flow and hepatic oxygenation were increased by RLN in early cirrhosis. Treatment of human HSC‐MFs with RLN inhibited contractility and induced an antifibrogenic phenotype in an RXFP1‐dependent manner. Conclusion: We identified RXFP1 as a potential new therapeutic target for PHT and MF activation status. (Hepatology 2014;59:1492‐1504)

Characterisation of a Novel Fc Conjugate of Macrophage Colony-stimulating Factor

We have produced an Fc conjugate of colony-stimulating factor (CSF) 1 with an improved circulating half-life. CSF1-Fc retained its macrophage growth-promoting activity, and did not induce proinflammatory cytokines in vitro. Treatment with CSF1-Fc did not produce adverse effects in mice or pigs. The impact of CSF1-Fc was examined using the Csf1r-enhanced green fluorescent protein (EGFP) reporter gene in MacGreen mice. Administration of CSF1-Fc to mice drove extensive infiltration of all tissues by Csf1r-EGFP positive macrophages. The main consequence was hepatosplenomegaly, associated with proliferation of hepatocytes. Expression profiles of the liver indicated that infiltrating macrophages produced candidate mediators of hepatocyte proliferation including urokinase, tumor necrosis factor, and interleukin 6. CSF1-Fc also promoted osteoclastogenesis and produced pleiotropic effects on other organ systems, notably the testis, where CSF1-dependent macrophages have been implicated in homeostasis. However, it did not affect other putative CSF1 targets, notably intestine, where Paneth cell numbers and villus architecture were unchanged. CSF1 has therapeutic potential in regenerative medicine in multiple organs. We suggest that the CSF1-Fc conjugate retains this potential, and may permit daily delivery by injection rather than continuous infusion required for the core molecule.

Systematic review: the effects of autologous stem cell therapy for patients with liver disease

As morbidity and mortality from liver disease continues to rise, new strategies are necessary. Liver transplantation is not only an expensive resource committing the patient to lifelong immunosuppression but also suitable donor organs are in short supply. Against this background, autologous stem cell therapy has emerged as a potential treatment option.

The MacBlue Binary Transgene (csf1r-gal4VP16/UAS-ECFP) Provides a Novel Marker for Visualisation of Subsets of Monocytes, Macrophages and Dendritic Cells and Responsiveness to CSF1 Administration

The MacBlue transgenic mouse uses the Csf1r promoter and first intron to drive expression of gal4-VP16, which in turn drives a cointegrated gal4-responsive UAS-ECFP cassette. The Csf1r promoter region used contains a deletion of a 150 bp conserved region covering trophoblast and osteoclast-specific transcription start sites. In this study, we examined expression of the transgene in embryos and adult mice. In embryos, ECFP was expressed in the large majority of macrophages derived from the yolk sac, and as the liver became a major site of monocytopoiesis. In adults, ECFP was detected at high levels in both Ly6C+ and Ly6C- monocytes and distinguished them from Ly6C+, F4/80+, CSF1R+ immature myeloid cells in peripheral blood. ECFP was also detected in the large majority of microglia and Langerhans cells. However, expression was lost from the majority of tissue macrophages, including Kupffer cells in the liver and F4/80+ macrophages of the lung, kidney, spleen and intestine. The small numbers of positive cells isolated from the liver resembled blood monocytes. In the gut, ECFP+ cells were identified primarily as classical dendritic cells or blood monocytes in disaggregated cell preparations. Immunohistochemistry showed large numbers of ECFP+ cells in the Peyers patch and isolated lymphoid follicles. The MacBlue transgene was used to investigate the effect of treatment with CSF1-Fc, a form of the growth factor with longer half-life and efficacy. CSF1-Fc massively expanded both the immature myeloid cell (ECFP−) and Ly6C+ monocyte populations, but had a smaller effect on Ly6C− monocytes. There were proportional increases in ECFP+ cells detected in lung and liver, consistent with monocyte infiltration, but no generation of ECFP+ Kupffer cells. In the gut, there was selective infiltration of large numbers of cells into the lamina propria and Peyers patches. We discuss the use of the MacBlue transgene as a marker of monocyte/macrophage/dendritic cell differentiation.

The relationships between hamstring flexibility, lumbar flexion, and low back pain in rowers

Abstract In this study, we examined the relationships between low back pain, hamstring flexibility, and lumbar flexion in rowers. Twenty-six male university rowers participated. Hamstring flexibility was assessed using an adjusted straight leg raise technique, and lumbar flexion was assessed via a distraction of skin marks protocol while long sitting. A questionnaire ascertained rowing details and low back pain characteristics. Low back pain was highly prevalent. No association was observed between low back pain and hamstring flexibility, or between hamstring flexibility and lumbar flexion. Sufferers of low back pain showed reduced lumbar flexion (P=0.03; 95% confidence interval = − 3.7 to −0.2). Results obtained using the adjusted straight leg raise technique suggested that low back pain was not associated with hamstring inflexibility, which suggests that increasing hamstring flexibility for rehabilitation or prevention of low back pain in rowers might not be necessary.

Randomized clinical trial of perioperative nerve block and continuous local anaesthetic infiltration via wound catheter versus epidural analgesia in open liver resection (LIVER 2 trial)

Analgesia after liver surgery remains controversial. A previous randomized trial of continuous wound infiltration (CWI) versus thoracic epidural analgesia (TEA) after liver surgery (LIVER trial) showed a faster recovery time in the wound infiltration group but better early postoperative pain scores in the TEA group. High‐level evidence is, however, limited and opinion remains divided. The aim was to determine whether there is a difference in functional recovery time between patients having CWI plus abdominal nerve blocks versus TEA after liver resection.

Implant-based augmentation mammaplasty following breast conservation surgery

BackgroundImplant-based augmentation mammaplasty following breast-conserving cancer therapy (BCT) and radiotherapy has previously been cautioned against given concerns over complications and potential occult recurrence. MethodsAll patients who underwent BCT and radiotherapy followed by implant-based augmentation mammaplasty were included in the study. Retrospective case-note analysis was performed. ResultsIn all, 23 delayed implant-based mammaplasty procedures following BCT for breast cancer were performed. Fifteen tumors were located in the superior half of the breast. The median weight of wide local excision was 71.0 g (range, 15–385). All implants were placed in a subglandular position with median volume of 140 mL (range, 80–370). Complications occurred in 10 breasts, and 6 breasts required revisional surgery. Capsular contracture occurred in 4 breasts. No patient developed locoregional recurrence. A questionnaire revealed excellent satisfaction of the patient, and all patients reported that they definitely or probably would recommend the procedure. ConclusionsDelayed implant-based augmentation mammaplasty after BCT and radiotherapy is feasible and gives good aesthetic results with high satisfaction of the patient. This technique is an important addition to the breast conservation surgery algorithm.

Aerosolized Local Anaesthetic to Reduce Postoperative Pain

McDermott et al. present a well-conducted randomised controlled trial to assess the effects of aerosolized intraperitoneal anaesthesia on postoperative pain following laparoscopic procedures [1]. This group and others have previously reported that shoulder tip pain following laparoscopic surgery may be experienced by a considerable proportion of patients, and this can delay postoperative progress [2, 3]. The ability to deliver a pre-emptive analgesic effect offers the opportunity to reduce postoperative analgesic requirement, facilitate earlier hospital discharge, reduce costs and ultimately improve the patient experience. In the present study, McDermott et al. used a novel device called the AeroSurge , which the group had previously shown to be safe and effective at delivering intraperitoneal aerosolized anaesthetic [4]. The group inserted the AeroSurge device through a 10-mm port and attached to a CO2 pump, filling the peritoneal cavity with aerosolized ropivacaine (treatment group) or normal saline (control). The theory being that by delivering aerosolized anaesthetic to the peritoneal cavity, the stimulation of pain receptors caused by insufflation that results in shoulder tip pain may be reduced. Other randomised controlled trials using a similar aerosolized approach have been encouraging, demonstrating reduced pain scores following laparoscopic cholecystectomy [5, 6]. McDermott et al. included two very different, but common, laparoscopic procedures: cholecystectomy and Nissen fundoplication. While the inclusion of these two procedures has facilitated achievement of the recruitment target (determined by their pre-trial power calculation), the variability in length of procedure, port positioning, size of trocars, and technical aspects (such as the potential for pneumomediastinum with fundoplication) limits interpretation of the results. While overall no benefit to the primary outcome measure (shoulder tip pain at 6 h) was demonstrated, subgroup analysis suggested that there was a reduction in early postoperative pain following laparoscopic cholecystectomy. While the study is underpowered for demonstration of benefit in this subgroup, the results are encouraging when taken in the context of previous studies which also demonstrate benefit using a similar approach [5, 6]. Ultimately effective reduction of postoperative pain is likely to require a multimodal approach. Other techniques which have been shown to be of benefit in this setting include low pressure pneumoperitoneum, pulmonary recruitment manoeuvres and peritoneal infiltration of local anaesthetic [7–9]. Techniques such as subdiaphragmatic normal saline irrigation and drain placement to minimise postoperative pneumoperitoneum have not proved so effective [10, 11]. By determining the most appropriate surgical indications and optimising the administration regimen, aerosolized intraperitoneal anaesthesia may have a role in improving the postoperative experience of patients undergoing laparoscopic surgery.