Melatonin compensates silencing of heat shock protein 70 and suppresses ultraviolet radiation‐induced inflammation in human skin ex vivo and cultured keratinocytes

Melatonin, a lipophilic compound synthesized and released from the pineal gland, effectively acts against ultraviolet radiation (UVR), one of the main inducers of epidermal damage, skin cancer, inflammation, and DNA photo damage. One of the common known stress protein induced by UVR is heat shock protein 70 (Hsp70), highly expressed in human keratinocytes, providing cellular resistance to such stressors. Here, using human full‐thickness skin and normal human epidermal keratinocytes (NHEK), we investigated the interaction of melatonin and Hsp70 toward UVR‐induced inflammatory and apoptotic responses. The following observations were made: (i) UVR upregulated Hsp70 gene expression in human epidermis while melatonin significantly inverted this effect, (ii) similar patterns of regulation were observed within Hsp70 protein level, and (iii) mechanistic studies involving silencing of Hsp70 RNA (Hsp70 siRNA) showed prominent decrease of IκB‐α (an inhibitor of NF‐κB) and enhanced gene expression of pro‐inflammatory cytokines (IL‐1β, IL‐6, Casp‐1) and pro‐apoptotic protein (Casp‐3) in NHEK. Parallel investigation using melatonin (10^?3 m ) significantly inverted these responses regardless depletion of Hsp70 RNA suggesting a compensatory action of this compound in the defense mechanisms. Our findings combined with data reported so far thus enrich existing knowledge about the potent anti‐apoptotic and anti‐inflammatory action of melatonin.     

Polyarteritis Nodosa-Induced Pancreaticoduodenal Artery Aneurysmal Rupture

Polyarteritis nodosa (PAN) is a systemic, necrotizing vasculitis of small- and medium-sized arteries typically with multiorgan involvement. Most cases of PAN are idiopathic, although hepatitis B or C virus infections and hairy cell leukemia are important in the pathogenesis of some cases. PAN is characterized as segmental transmural inflammation of muscular arteries. Diagnosis is based on clinical suspicion, a negative immunofluorescence test for antineutrophil cytoplasmic antibodies, and whenever possible, biopsy conformation. Angiographic images may reveal microaneurysms affecting the renal, hepatic, or mesenteric vasculature. Aneurysmal formation and rupture are important complications that can be fatal. Treatment may warrant immunosuppression with steroids and cyclophosphamide. If left untreated, PAN can be fatal. To our knowledge, we report the second documented case of PAN-induced ruptured inferior pancreaticoduodenal artery aneurysm.     

Central and peripheral body fat distribution: Different associations with low-grade inflammation in young adults?

Background and aimsEvidence regarding the impact of regional body fat distribution on low-grade inflammation is limited. The current study examined the association of central and peripheral body fat distribution and low-grade inflammation levels in young adults, considering collinearity between variables.Methods and resultsA cross-sectional analysis of 809 adults (aged 27 years) was conducted as part of the EPITeen cohort, Porto, Portugal. Regional body fat was measured by dual-energy X-ray absorptiometry scan (DXA) and serum high-sensitivity C-reactive protein (hsCRP) was measured in a fasting blood sample. OLS (ordinary least squares) and LASSO (least absolute shrinkage and selection operator) regression models were fitted to estimate the association of trunk and peripheral fat with hsCRP, stratified by sex. Using OLS regression, trunk fat in females was positively associated with ln(hsCRP) (β₁ = 0.064, 95% CI 0.018; 0.109). The effect of peripheral fat on ln(hsCRP) was shown not to be significantly different from trunk fat (β₂ = −0.011, 95% CI −0.110; 0.089), but no statistically significant association was observed (β₃ = 0.053, 95% CI −0.004; 0.110) between peripheral fat and ln(hsCRP). In males, trunk fat also showed a positive association with ln(hsCRP) (β₁ = 0.104, 95% CI 0.055; 0.154), and the effect of peripheral fat on ln(hsCRP) was shown to be significantly different from trunk fat (β₂ = −0.124, 95% CI −0.237;−0.011). However, the association between peripheral fat and ln(hsCRP) did not reach statistical significance (β₃ = −0.020, 95% CI −0.086; 0.046). The results of OLS were confirmed by LASSO regression.ConclusionA higher fat deposited in the trunk was positively associated with hsCRP, whereas no statistically significant effect was observed for peripheral fat.     

Effect of collagenase ointment versus moist exposed burn ointment on healing of full‐thickness burns in mice by removing of necrotic tissue

The presence of necrotic tissue is one of the major problems that affect healing of burn wounds. The present study was designed to find the effectiveness of collagenase versus moist exposed burn ointment (MEBO) on removal of necrotic tissue of burns. Twenty mice randomly assigned and divided into four groups. For Group 1, burn wounds were treated with collagenase ointment only, Group 2 burn wounds were treated with MEBO, Group 3 burn wounds were treated with white vaseline alone, and Group 4 burn wounds were considered as control and left without treatment. In each group, the time of treatment was considered. The results indicated that the removal time of necrotic tissue and healing process was better in the case of using collagenase than using MEBO for treatment of burns.     

单纯性肥胖症学龄儿童肝脏脂肪含量的MRI研究

目的分析学龄儿童单纯性肥胖症的MRI表现及MRS特点,确定其肝脏脂肪的MRI定量评估方法。方法将2015年1月—2016年12月期间临床诊断单纯性肥胖症的学龄儿童52例(男31例,女21例)作为病例组,平均年龄(10.1±1.1)岁。同年龄组[平均年龄(9.8±0.9)岁]的正常健康儿童40例(男22例,女18例)作为对照组。采用SIEMENS 1.5 T Avanto MR设备行MRI和~1H-MRS检查。观察肝实质于同相位、反相位影像上的信号变化;通过~1H-MRS获得肝脏兴趣区的水峰峰值(P_w)、水峰下面积(A_w)、脂峰峰值(P_l)及脂峰下面积(A_l)并计算出脂肪分数(FF)。采用独立样本t检验比较正常儿童和肥胖症患儿间P_w、A_w、P_l、A_l、FF差异;采用单因素方差分析比较轻、中、重度肥胖症患儿间各项指标的差异。并利用受试者操作特征(ROC)曲线评估MRS诊断脂肪肝的敏感度、特异度及准确度。结果肥胖症患儿组于T_1WI反相位影像上信号不同程度减低,而正常组T_1WI同反相位影像信号一致。MRS结果如下:(1)正常组和肥胖症组的P_w、A_w差异无统计学意义(P0.05)。(2)肥胖症患儿P_l、A_l、FF明显高于正常组(均P0.05);其中FF的诊断效能最高,敏感度为100%,特异度为82%,准确度为85%。(3)随着肥胖分级的增加,肥胖患儿的P_l、A_l均增高。结论 T_1WI双回波同反相位技术和MRS是目前定量测量肝脏脂肪含量的有效方法,在前者对脂肪肝做出初步诊断的基础上, MRS可进一步对脂肪肝进行量化分级。