Primary sclerosing cholangitis (PSC) and inflammatory bowel disease (IBD): a condition exemplifying the crosstalk of the gut-liver axis.

The close relationship between primary sclerosing cholangitis (PSC) and inflammatory bowel disease (IBD) provides a good opportunity to comprehend the gut-liver axis. The gut and the liver have reciprocal interactions, including how gut inflammation influences the liver through immune cells and the microbiota and how the microbiota in the gut modifies bile acids, which are produced and secreted from the liver. PSC-IBD shows distinct clinical findings from classical IBD. In addition, a distinct genetic predisposition and unique microbiota composition suggest that PSC-IBD is an independent disease entity. Understanding the pathogenesis of PSC-IBD helps to develop novel and effective therapeutic agents. Given the high risk of malignancies associated with PSC-IBD, it is critical to identify patients at high risk and implement appropriate surveillance and monitoring strategies. In this review, we provide an overview of PSC-IBD, which exemplifies the gut-liver axis.

Treatment of primary sclerosing cholangitis combined with inflammatory bowel disease.

Primary sclerosing cholangitis (PSC) is a progressive cholestatic, inflammatory, and fibrotic disease that is strongly associated with inflammatory bowel disease (IBD). PSC-IBD represents a unique disease entity and patients with this disease have an increased risk of malignancy development, such as colorectal cancer and cholangiocarcinoma. The pathogenesis of PSC-IBD involves genetic and environmental factors such as gut dysbiosis and bile acids alteration. However, despite the advancement of disease characteristics, no effective medical therapy has proven to have a significant impact on the prognosis of PSC. The treatment options for patients with PSC-IBD do not differ from those for patients with PSC alone. Potential candidate drugs have been developed based on the pathogenesis of PSC-IBD, such as those that target modulation of bile acids, inflammation, fibrosis, and gut dysbiosis. In this review, we summarize the current medical treatments for PSC-IBD and the status of new emerging therapeutic agents.

Inhibition of Heat Shock Factor 1 Signaling Decreases Hepatoblastoma Growth via Induction of Apoptosis.

Although rare compared with adult liver cancers, hepatoblastoma (HB) is the most common pediatric liver malignancy, and its incidence is increasing. Currently, the treatment includes surgical resection with or without chemotherapy, and in severe cases, liver transplantation in children. The effort to develop more targeted, HB-specific therapies has been stymied by the lack of fundamental knowledge about HB biology. Heat shock factor 1 (HSF1), a transcription factor, is a canonical inducer of heat shock proteins, which act as chaperone proteins to prevent or undo protein misfolding. Recent work has shown a role for HSF1 in cancer beyond the canonical heat shock response. The current study found increased HSF1 signaling in HB versus normal liver. It showed that less differentiated, more embryonic tumors had higher levels of HSF1 than more differentiated, more fetal-appearing tumors. Most strikingly, HSF1 expression levels correlated with mortality. This study used a mouse model of HB to test the effect of inhibiting HSF1 early in tumor development on cancer growth. HSF1 inhibition resulted in fewer and smaller tumors, suggesting HSF1 is needed for aggressive tumor growth. Moreover, HSF1 inhibition also increased apoptosis in tumor foci. These data suggest that HSF1 may be a viable pharmacologic target for HB treatment.

Effect of inspiratory flow rate on the efficiency of carbon dioxide removal at tidal volumes below instrumental dead space.

OBJECTIVE: The ability to ventilate babies with tidal volumes (VTs) below dead space has been demonstrated both in vivo and in vitro, though it appears to violate classical respiratory physiology. We hypothesised that this phenomenon is made possible by rapid flow of gas that penetrates the dead space allowing fresh gas to reach the lungs and that the magnitude of this phenomenon is affected by flow rate or how rapidly air flows through the endotracheal tube. METHODS: We conducted two bench experiments. First, we measured the time needed for complete CO2 washout from a test lung to assess how fixed VT but different inflation flow rates affect ventilation. For the second experiment, we infused carbon dioxide at a low rate into the test lung, varied the inflation flow rate and adjusted the VT to maintain stable end tidal carbon dioxide (ETCO2). RESULTS: At all tested VTs, lower flow rate increased the time it took for CO2 to washout from the test lung. The effect was most pronounced for VTs below dead space. The CO2 steady-state experiment showed that ETCO2 increased when the flow rate decreased. Ventilating with a slower flow rate required a nearly 20% increase in VT for the same effective alveolar ventilation. CONCLUSIONS: Inflation flow rate affects the efficiency of CO2 removal with low VT. Our results are relevant for providers using volume-controlled ventilation or other modes that use low inflation flow rates because the VT required for normocapnia will be higher than published values that were generated using pressure-limited ventilation modes with high inflation flows.

Leclercia Adecarboxylata Infection in an Immunocompetent Child.

Leclercia adecarboxylata is a motile Gram negative rod that is not often pathogenic in immunocompetent patients. We will present the first case report of a L. adecarboxylata in a pediatric patient with no systemic medical disease and present a detailed literature review.

Differences in perspective on prognosis and treatment of children with trisomy 18.

Differences in perspective between physicians caring for children with trisomy 18 may be confusing and stressful for parents. The hypothesis of this study was that neonatologists and pediatric pulmonologists differ in their opinions regarding long-term prognosis and recommended interventions. Neonatologists and pediatric pulmonologists in New York State were surveyed. Respondents were asked to report their personal experience caring for affected children, opinions on prognosis, major influences on their opinions, and their likelihood of recommending specific medical or surgical interventions for two clinical vignettes. A total of 393 surveys were mailed, 327 to neonatologists and 66 to pediatric pulmonologists. Sixty-six (20%) neonatologists and 21 (32%) pediatric pulmonologists completed the survey. Neonatologists had cared for more patients with trisomy 18. Twenty-nine percent of pediatric pulmonologists had never cared for a patient with trisomy 18 compared to 2% of neonatologists, P < 0.001. Pediatric pulmonologists were more likely to recommend almost all interventions including antibiotics for pneumonia, mechanical ventilation, cardiac and orthopedic surgery, and "full code resuscitation." Neonatologists were more likely to recommend comfort care only or palliative care. Fifty-four percent of neonatologists and 5% of pediatric pulmonologists thought patients with trisomy 18 without significant congenital heart disease would die before age one despite aggressive medical care, P < 0.001. The major influences impacting these recommendations also varied. Pediatric pulmonologists are more optimistic about the prognosis for children than neonatologists and more likely to recommend medical and surgical interventions. Experience with the condition and perception of survivability may contribute to these differences in approach.