DNA methylation-associated colonic mucosal immune and defense responses in treatment-na?ve pediatric ulcerative colitis

Inflammatory bowel diseases (IBD) are emerging globally, indicating that environmental factors may be important in their pathogenesis. Colonic mucosal epigenetic changes, such as DNA methylation, can occur in response to the environment and have been implicated in IBD pathology. However, mucosal DNA methylation has not been examined in treatment-naïve patients. We studied DNA methylation in untreated, left sided colonic biopsy specimens using the Infinium HumanMethylation450 BeadChip array. We analyzed 22 control (C) patients, 15 untreated Crohn’s disease (CD) patients, and 9 untreated ulcerative colitis (UC) patients from two cohorts. Samples obtained at the time of clinical remission from two of the treatment-naïve UC patients were also included into the analysis. UC-specific gene expression was interrogated in a subset of adjacent samples (5 C and 5 UC) using the Affymetrix GeneChip PrimeView Human Gene Expression Arrays. Only treatment-naïve UC separated from control. One-hundred-and-twenty genes with significant expression change in UC (> 2-fold, P < 0.05) were associated with differentially methylated regions (DMRs). Epigenetically associated gene expression changes (including gene expression changes in the IFITM1, ITGB2, S100A9, SLPI, SAA1, and STAT3 genes) were linked to colonic mucosal immune and defense responses. These findings underscore the relationship between epigenetic changes and inflammation in pediatric treatment-naïve UC and may have potential etiologic, diagnostic, and therapeutic relevance for IBD.     

儿童颈髓区巨大动静脉畸形1例(英文)

脑动静脉畸形(AVM)是复杂的血管病变,是由于没有毛细血管床的脑动脉和静脉之间的异常连接引起的病灶[1]。脑动静脉畸形的临床表现有大出血、癫痫、神经功能障碍或头痛,但大部分患者无特异性症状,因此容易漏诊、误诊。手术切除、血管内治疗和放射治疗是动静脉畸形的选择疗法。血管内治疗可以作为其他难以治愈的脑动静脉畸形,或者作为手术切除或放射治疗前的辅助治疗,以减少脑动静脉畸形的血供或促进其收缩,进而促进手术切除或消融[2]。该病引起的颈部疼痛在儿科未见报道。我们收治1例颈髓区巨大动静脉畸形患儿,表现为持续性颈部疼痛并出现癫痫和呕吐症状,经采取分段外科胶栓塞术(第一次部分栓塞术后观察1年再行第二次栓塞),达到动静脉畸形的治愈。     

Circulating soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) as diagnostic and prognostic marker in neonatal sepsis

ObjectiveTriggering receptor expressed on myeloid cells-1 (TREM-1) is an important receptor involved in the innate inflammatory response and sepsis. We assessed soluble TREM-1 (sTREM-1) in 112 septic neonates (63 culture-positive and 49 culture-negative) and 40 healthy controls as a potential early diagnostic and prognostic marker for neonatal sepsis (NS).MethodsStudied neonates were evaluated for early- or late-onset sepsis using clinical and laboratory indicators upon admission. sTREM-1 was measured on initial sepsis evaluation and at 48 h after antibiotic therapy. For ethical reasons, cord blood samples were collected from control neonates and only samples from neonates that proved to be healthy by clinical examination and laboratory analysis were further analyzed for sTREM-1.ResultsBaseline sTREM-1 levels were significantly elevated in culture-proven (1461.1 ± 523 pg/mL) and culture-negative sepsis (1194 ± 485 pg/mL) compared to controls (162.2 ± 61 pg/mL) with no significant difference between both septic groups. Culture-positive or negative septic preterm neonates had significantly higher sTREM-1 compared to full term neonates. sTREM-1 was significantly higher in neonates with early sepsis than late sepsis and was associated with high mortality. sTREM-1 was significantly decreased 48 h after antibiotic therapy compared to baseline or levels in neonates with persistently positive cultures. sTREM-1 was positively correlated to white blood cells (WBCs), absolute neutrophil count, immature/total neutrophil (I/T) ratio, C-reactive protein (hs-CRP) and sepsis score while negatively correlated to gestational age and weight. hs-CRP and sepsis score were independently related to sTREM-1 in multiregression analysis. sTREM-1 cutoff value of 310 pg/mL could be diagnostic for NS with 100% sensitivity and specificity (AUC, 1.0 and 95% confidence interval [CI], 0.696–1.015) while the cutoff value 1100 pg/mL was predictive of survival with 100% sensitivity and 97% specificity (AUC, 0.978 and 95% CI, 0.853–1.13). However, hs-CRP cutoff 13.5 mg/L could be diagnostic for NS with a sensitivity of 76% and specificity of 72% (AUC, 0.762 and 95% CI, 0.612–0.925) and levels were not related to survival as no significant difference was found between dead and alive septic neonates.ConclusionsElevated sTREM-1 could be considered an early marker for NS that reflects sepsis severity and poor prognosis.     

Non-Invasive Model of Neuropathogenic Escherichia coli Infection in the Neonatal Rat

Investigation of the interactions between animal host and bacterial pathogen is only meaningful if the infection model employed replicates the principal features of the natural infection. This protocol describes procedures for the establishment and evaluation of systemic infection due to neuropathogenic Escherichia coli K1 in the neonatal rat. Colonization of the gastrointestinal tract leads to dissemination of the pathogen along the gut-lymph-blood-brain course of infection and the model displays strong age dependency. A strain of E. coli O18:K1 with enhanced virulence for the neonatal rat produces exceptionally high rates of colonization, translocation to the blood compartment and invasion of the meninges following transit through the choroid plexus. As in the human host, penetration of the central nervous system is accompanied by local inflammation and an invariably lethal outcome. The model is of proven utility for studies of the mechanism of pathogenesis, for evaluation of therapeutic interventions and for assessment of bacterial virulence.     

Enzymatic changes in myosin regulatory proteins may explain vasoplegia in terminally ill patients with sepsis

The current study was conducted with the hypothesis that failure of maintenance of the vascular tone may be central to failure of the peripheral circulation and spiralling down of blood pressure in sepsis. Namely, we examined the balance between expression of myosin light chain (MLC) phosphatase and kinase, enzymes that regulate MLCs dephosphorylation and phosphorylation with a direct effect on pharmacomechanical coupling for smooth muscle relaxation and contraction respectively. Mechanical recordings and enzyme immunoassays of vascular smooth muscle lysates were used as the major methods to examine arterial biopsy samples from terminally ill sepsis patients. The results of the present study provide evidence that genomic alteration of expression of key regulatory proteins in vascular smooth muscles may be responsible for the relentless downhill course in sepsis. Down-regulation of myosin light chain kinase (MLCK) and up-regulation of MLCK may explain the loss of tone and failure to mount contractile response in vivo during circulation. The mechanical studies demonstrated the inability of the arteries to develop tone when stimulated by phenylephrine in vitro. The results of our study provide indirect hint that control of inflammation is a major therapeutic approach in sepsis, and may facilitate to ameliorate the progressive cardiovascular collapse.     

Peptidylarginine deiminase 4 concentration,but not PADI4 polymorphisms,is associated with ICU mortality in septic shock patients

The objective of our study was to evaluate the association between peptidylarginine deiminase 4 (PAD4) concentration and its polymorphisms with mortality in patients with septic shock . We prospectively evaluated 175 patients aged over 18 years with septic shock upon intensive care unit (ICU) admission. However, 48 patients were excluded. Thus, 127 patients were enrolled in the study. At the time of the patients’ enrollment, demographic information was recorded. Blood samples were taken within the first 24 hours of the patient's admission to determine serum PAD4 concentrations and its polymorphism PADI4_89 [rs11203366], PADI4_94 [rs2240340] and PADI4_104 [rs1748033]. The mean age was 63.3 ± 15.2 years, 56.7% were male, PAD4 concentration was 4.62 (2.48‐6.20) ng/mL and the ICU mortality rate was 67.7%. The patients who died in the ICU had higher APACHE II and Sequential Organ Failure Assessment (SOFA) scores. In addition, PAD4 concentration was higher in patients who died during ICU stay. However, there were no differences regarding PADI4 polymorphisms and ICU mortality. In the logistic regression models, PAD4 concentrations were associated with ICU mortality when adjusted for APACHE II score and lactate (OR: 1.477; CI 95%: 1.186‐1.839; P < .001), and when adjusted for age, gender and APACHE II score (OR: 1.392; CI 95%: 1.145‐1.692; P < .001). In conclusion, PAD4 concentration, but not PADI4_89, PADI4_94 and PADI4_104 polymorphisms, is associated with ICU mortality in septic shock patients.     

Salvianolic acid B protects against acute lung injury by decreasing TRPM6 and TRPM7 expressions in a rat model of sepsis

This study aimed to investigate the protective effects of salvianolic acid B (SA‐B) on acute lung injury (ALI) through decreasing the expressions of channel kinase's TRPM6 and TRPM7. Wistar Septic rat models were established by lipopolysaccharide (LPS), which were separated into the control, lipopolysaccharide (LPS), SA‐B, SA‐B + si‐TRPM6, SA‐B + si‐TRPM7, si‐TRPM6, and si‐TRPM7 groups. Arterial blood gas, protein content, total white blood cell (WBC) count and the percentage of polymorphonuclear neutrophils (PMN%) were measured. Levels of TNF‐α and IL‐6 levels in bronchoalveolar lavage fluid (BALF) were monitored. Lung coefficient, myeloperoxidase (MPO) and superoxide dismutase (SOD) activity were conducted by MPO and SOD kit. The mRNA expressions of TRPM6 and TRPM7 were detected by qRT‐PCR. Compared with the control group, the PaO₂ and PaO₂/FiO₂ values exhibited decreases in other group, while the PaCO₂ value_, protein content, total WBC, PMN%, TNF‐α, IL‐6 levels and lung coefficient values all increased. MPO activity in lung tissue increased, while SOD activity decreased. TRPM6 and TRPM7 expressions increased significantly. Compared with the LPS group, the SA‐B, SA‐B + si‐TRPM6, SA‐B + si‐TRPM7, si‐TRPM6, and si‐TRPM7 groups had increased PaO₂ and the PaO₂/FiO₂, while decreased PaCO_2, protein content, total WBC, PMN%, TNF‐α, IL‐6 levels, and lung coefficient. MPO activity in lung tissue decreased while SOD activity increased. Decreased mRNA expressions of TRPM6 and TRPM7 in the SA‐B, SA‐B + si‐TRPM6, and SA‐B + si‐TRPM6 groups were observed. Through decreasing the expressions of the channel kinase TRPM6 and TRPM7, SA‐B protects against ALI in septic rats.