Impact of Z score system on the management of coronary artery lesions in Kawasaki disease.

BACKGROUND: Coronary artery aneurysms are well-described in Kawasaki disease and the Multisystem Inflammatory Syndrome in Children and are graded using Z scores. Three Z score systems (Boston, Montreal, and DC) are widely used in North America. The recent Pediatric Heart Network Z score system is derived from the largest diverse sample to-date. The impact of Z score system on the rate of coronary dilation and management was assessed in a large real-world dataset. METHODS: Using a combined dataset of patients with acute Kawasaki disease from the Children's Hospital at Montefiore and the National Heart, Lung, and Blood Institute Kawasaki Disease Study, coronary Z scores and the rate of coronary lesions (Z ≥ 2.0) and aneurysms (Z ≥ 2.5) were determined using four Z score systems. Agreement among Z scores and the effect on Kawasaki management were assessed. RESULTS: Of 333 patients analysed, 136 were from Montefiore and 197 from the Kawasaki Disease Study. Age, sex, body surface area, and rate of coronary lesions did not differ between the samples. Among the four Z score systems, the rate of acute coronary lesions varied from 24 to 55%. The mean left anterior descending Z scores from Pediatric Heart Network and Boston had a large uniform discrepancy of 1.3. Differences in Z scores among the four systems may change anticoagulation management in up to 22% of a Kawasaki population. CONCLUSIONS: Choice of Z score system alone may impact Kawasaki disease diagnosis and management. Further research is necessary to determine the ideal coronary Z score system.

Functional role of cellular senescence in biliary injury.

Cellular senescence is a state of irreversible cell cycle arrest that has been involved in many gastrointestinal diseases, including human cholestatic liver disorders. Senescence may play a role in biliary atresia, primary sclerosing cholangitis, cellular rejection, and primary biliary cirrhosis, four liver diseases affecting cholangiocytes and the biliary system. In this review, we examine proposed mechanisms of senescence-related biliary diseases, including hypotheses associated with the senescence-associated phenotype, induction of senescence in nearby cells, and the depletion of stem cell subpopulations. Current evidence for the molecular mechanisms of senescence in the previously mentioned diseases is discussed in detail, with attention to recent advances on the role of pathways associated with senescence-associated phenotype, stress-induced senescence, telomere dysfunction, and autophagy.

Overexpression of membrane metalloendopeptidase inhibits substance P stimulation of cholangiocarcinoma growth.

Substance P (SP) promotes cholangiocyte growth during cholestasis by activating its receptor, NK1R. SP is a proteolytic product of tachykinin (Tac1) and is deactivated by membrane metalloendopeptidase (MME). This study aimed to evaluate the functional role of SP in the regulation of cholangiocarcinoma (CCA) growth. NK1R, Tac1, and MME expression and SP secretion were assessed in human CCA cells and nonmalignant cholangiocytes. The proliferative effects of SP (in the absence/presence of the NK1R inhibitor, L-733,060) and of L-733,060 were evaluated. In vivo, the effect of L-733,060 treatment or MME overexpression on tumor growth was evaluated by using a xenograft model of CCA in nu/nu nude mice. The expression of Tac1, MME, NK1R, PCNA, CK-19, and VEGF-A was analyzed in the resulting tumors. Human CCA cell lines had increased expression of Tac1 and NK1R, along with reduced levels of MME compared with nonmalignant cholangiocytes, resulting in a subsequent increase in SP secretion. SP treatment increased CCA cell proliferation in vitro, which was blocked by L-733,060. Treatment with L-733,060 alone inhibited CCA proliferation in vitro and in vivo. Xenograft tumors derived from MME-overexpressed human Mz-ChA-1 CCA cells had a slower growth rate than those derived from control cells. Expression of PCNA, CK-19, and VEGF-A decreased, whereas MME expression increased in the xenograft tumors treated with L-733,060 or MME-overexpressed xenograft tumors compared with controls. The study suggests that SP secreted by CCA promotes CCA growth via autocrine pathway. Blockade of SP secretion and NK1R signaling may be important for the management of CCA.