Gene expression of early hypertrophic scar tissue screened by means of cDNA microarrays

BACKGROUND: Hypertrophic scar is an excessive healing response that often follows thermal injury. The most outstanding morphologic change is the overdeposition of collagen, which is caused by imbalance between synthesis and metabolism of collagen. Previous studies also found that transforming growth factor-beta was the key factor controlling scar formation. However, neither anti-transforming growth factor-beta nor other methods could completely control scar formation and contraction. This fact suggests a multifactorial cause. Fortunately, cDNA microarray throws light on the general alteration at the gene level, and thus could allow us to find some new clues for understanding scar formation and contraction. METHODS: In this article, we report the results obtained from the scanning of gene expression of hypertrophic scar by means of cDNA microarray. Five cases of early human postburn hypertrophic scars were selected. Total tissue RNA was extracted from each hypertrophic scar sample and the corresponding uninjured region skin tissue; mRNA was further purified by Oligotex and then was reversely transcribed to cDNAs with the incorporation of fluorescent dUTP to prepare the hybridization probes. The mixed probes were hybridized to the cDNA microarray containing 4,096 genes on a type of chemical material-coated glass slide. After high-stringent washing, the hybridized slides were scanned for fluorescent signal detection. Then, the expression and distribution of cytoskeletal genes such as alpha-smooth muscle actin (alpha-SMA) gene; fibroblast tropomyosin TM30(pl) gene; vimentin gene; profilin gene; and BM40 gene of hypertrophic scar at 3, 6, 9, and 12 months age were further quantitatively studied by in situ hybridization or immunohistochemistry. RESULTS: Our data indicated that there were 94 genes overexpressed and 3 genes down-regulated in early postburn hypertrophic scar. These altered genes were related to proto-oncogenes, apoptosis, immune regulatory genes, cytoskeletal elements, metabolism, and so forth. We also found that the detected cytoskeletal gene expression was much more intense at all time points than the control group. Consistent with clinical observation, cytoskeletal genes reached a peak at an early stage and gradually decreased. CONCLUSION: Our study implied that multiple genes are involved in scar formation and contraction. Interferon is an autosecreted cytokine that might be responsible for self-control of overgrowth of cells in wounds. The early period of hypertrophic scar formation might be a good time for preventing overgrowth and contraction of hypertrophic scar by gene therapy.     

胆管癌组织中MMP-9的表达及其意义

目的　探讨基质金属蛋白酶 9(matrixmetalloproteinase 9,MMP 9)在胆管癌发展中的作用及与胆管癌浸润、转移和预后的关系。方法　应用免疫组织化学法 (S P法 )对 5 2例经手术和病理证实的胆管癌及 10例经手术切除的正常胆管壁标本进行MMP 9蛋白检测。结果　 (1)MMP 9表达在胆管癌组织、癌旁组织及正常胆管上皮组织阳性率分别为 84 6 % (4 4 /5 2 )、2 2 6 % (7/31)和 0 %(0 /10 ) ,有显著性差异 (P <0 0 1)。 (2 )在 5 2例胆管癌组织中 ,MMP 9表达分别与肿瘤的病理分级、TNM分期、浸润和转移及手术方式有关 (P <0 0 5 ) ,而与性别、年龄、肿瘤部位及大小无关 (P >0 0 5 )。 (3)MMP 9表达阳性患者一年生存率明显低于阴性者 (P <0 0 1)。结论　MMP 9表达与胆管癌发展、浸润和转移密切相关 ,检测MMP 9的表达有助于对胆管癌转移潜能和预后的判断。     

Hyperactive Transforming Growth Factor‐β1 Signaling Potentiates Skeletal Defects in a Neurofibromatosis Type 1 Mouse Model

Dysregulated transforming growth factor beta (TGF‐β) signaling is associated with a spectrum of osseous defects as seen in Loeys‐Dietz syndrome, Marfan syndrome, and Camurati‐Engelmann disease. Intriguingly, neurofibromatosis type 1 (NF1) patients exhibit many of these characteristic skeletal features, including kyphoscoliosis, osteoporosis, tibial dysplasia, and pseudarthrosis; however, the molecular mechanisms mediating these phenotypes remain unclear. Here, we provide genetic and pharmacologic evidence that hyperactive TGF‐β1 signaling pivotally underpins osseous defects in Nf1^flox/?;Col2.3Cre mice, a model which closely recapitulates the skeletal abnormalities found in the human disease. Compared to controls, we show that serum TGF‐β1 levels are fivefold to sixfold increased both in Nf1^flox/?;Col2.3Cre mice and in a cohort of NF1 patients. Nf1‐deficient osteoblasts, the principal source of TGF‐β1 in bone, overexpress TGF‐β1 in a gene dosage–dependent fashion. Moreover, Nf1‐deficient osteoblasts and osteoclasts are hyperresponsive to TGF‐β1 stimulation, potentiating osteoclast bone resorptive activity while inhibiting osteoblast differentiation. These cellular phenotypes are further accompanied by p21‐Ras–dependent hyperactivation of the canonical TGF‐β1–Smad pathway. Reexpression of the human, full‐length neurofibromin guanosine triphosphatase (GTPase)‐activating protein (GAP)‐related domain (NF1 GRD) in primary Nf1‐deficient osteoblast progenitors, attenuated TGF‐β1 expression levels and reduced Smad phosphorylation in response to TGF‐β1 stimulation. As an in vivo proof of principle, we demonstrate that administration of the TGF‐β receptor 1 (TβRI) kinase inhibitor, SD‐208, can rescue bone mass deficits and prevent tibial fracture nonunion in Nf1^flox/?;Col2.3Cre mice. In sum, these data demonstrate a pivotal role for hyperactive TGF‐β1 signaling in the pathogenesis of NF1‐associated osteoporosis and pseudarthrosis, thus implicating the TGF‐β signaling pathway as a potential therapeutic target in the treatment of NF1 osseous defects that are refractory to current therapies. © 2013 American Society for Bone and Mineral Research.     

The association of pre‐operative STOP‐BANG scores with postoperative critical care admission

The STOP‐BANG questionnaire screens for obstructive sleep apnoea. We retrospectively analysed the independent association of pre‐operative variables with postoperative critical care admission using multivariable logistic regression for patients undergoing elective surgery from January to December 2011. Of 5432 patients, 338 (6.2%) were admitted postoperatively to the critical care unit. In multivariate analysis, the odds ratios (95% CI) for critical care admission were: 2.2 (1.1–4.6), p = 0.037; 3.2 (1.2–8.1), p = 0.017; and 5.1 (1.8–14.9), p = 0.002, for STOP‐BANG scores of 4, 5 and ≥ 6, respectively. The odds ratio was also independently increased for: each year of age, 1.015 (1.004–1.026), p = 0.019; asthma, 1.6 (1.1–2.4), p = 0.016; obstructive sleep apnoea, 3.2 (1.9–5.6), p < 0.001; and for ASA physical status 2, 3 and ≥ 4, 2.1 (1.4–3.3), 6.5 (3.9–11.0), 6.3 (2.9–13.8), respectively, p < 0.001 for all.     

MK2 plays an important role for the increased vascular permeability that follows thermal injury

We previously reported Rho kinase is involved in vessel hyper-permeability caused by burns. Here we further explore the Rho kinase downstream signaling, it is found that its specific inhibitor Y27632 significantly diminishes the activation of JNK and p38 MAPKs but not ERK that induced by serum from burned rats (burn-serum). JNK activation was found involved in the expression of HUVEC adhesion molecules following thermal injury, although not in the process of stress fiber formation. Inhibition of various MAPKs by specific inhibitors showed that SB203580 (inhibitor of p38), but neither SP600125 (inhibitor of JNK) nor PD98059 (inhibitor of ERK), abolish activation of the p38 downstream kinase MK2. Demonstration of stress fibers by fluorescent-labeled phalloidin showed that inhibition of MK2, either by its specific inhibitor or by dominant negative adeno-viral-carried constructs, significantly reduced burn-serum-induced HUVEC stress-fiber formation, while inhibition of another downstream p38 MAPK kinase, PRAK, had no such effects. Transfection of dominant negative adeno-viral MK2 (Ad-MK2(A)) significantly inhibited thermal injury-induced blood vessel hyper-permeability in rats and, moreover, prolonged the survival of burned rats beyond 72 h following thermal injury. One of the mechanisms behind these phenomena is that Ad-MK2(A) causes a significant depression of burn-serum-induced HSP27-phosphorylation, while the adeno-viral transported dominant negative PRAK (Ad-PRAK(A)) does not block. Although the effect of blockade of MK2 through its adeno-viral approach requires further study and investigation of alternatives to know for sure, we may have found a new pathway behind thermal-injury-induced blood vessel hyper-permeability, namely: Rho kinase > p38 > MK2 > HSP27.     

Numerical Solution of Blow-Up Problems for Nonlinear Wave Equations on Unbounded Domains

The numerical solution of blow-up problems for nonlinear wave equations on unbounded spatial domains is considered. Applying the unified approach, which is based on the operator splitting method, we construct the efficient nonlinear local absorbing boundary conditions for the nonlinear wave equation, and reduce the nonlinear problem on the unbounded spatial domain to an initial-boundary-value problem on a bounded domain. Then the finite difference method is used to solve the reduced problem on the bounded computational domain. Finally, a broad range of numerical examples are given to demonstrate the effectiveness and accuracy of our method, and some interesting propagation and behaviors of the blow-up problems for nonlinear wave equations are observed.     

Age‐related changes in amygdala–frontal connectivity during emotional face processing from childhood into young adulthood

The ability to process and respond to emotional facial expressions is a critical skill for healthy social and emotional development. There has been growing interest in understanding the neural circuitry underlying development of emotional processing, with previous research implicating functional connectivity between amygdala and frontal regions. However, existing work has focused on threatening emotional faces, raising questions regarding the extent to which these developmental patterns are specific to threat or to emotional face processing more broadly. In the current study, we examined age‐related changes in brain activity and amygdala functional connectivity during an fMRI emotional face matching task (including angry, fearful, and happy faces) in 61 healthy subjects aged 7–25 years. We found age‐related decreases in ventral medial prefrontal cortex activity in response to happy faces but not to angry or fearful faces, and an age‐related change (shifting from positive to negative correlation) in amygdala–anterior cingulate cortex/medial prefrontal cortex (ACC/mPFC) functional connectivity to all emotional faces. Specifically, positive correlations between amygdala and ACC/mPFC in children changed to negative correlations in adults, which may suggest early emergence of bottom‐up amygdala excitatory signaling to ACC/mPFC in children and later development of top‐down inhibitory control of ACC/mPFC over amygdala in adults. Age‐related changes in amygdala–ACC/mPFC connectivity did not vary for processing of different facial emotions, suggesting changes in amygdala–ACC/mPFC connectivity may underlie development of broad emotional processing, rather than threat‐specific processing. Hum Brain Mapp 37:1684–1695, 2016. © 2016 Wiley Periodicals, Inc .     

Effect of rs1063843 in the CAMKK2 gene on the dorsolateral prefrontal cortex

Recently, a single nucleotide polymorphism (SNP) in the CAMKK2 gene (rs1063843) was found to be associated with lower expression of the gene in the dorsolateral prefrontal cortex (DLPFC) and with schizophrenia (SCZ) and deficits in working memory and executive function. However, the brain mechanism underlying this association is poorly understood. A functional magnetic resonance imaging (fMRI) study (N = 84 healthy volunteers) involving multiple cognitive tasks, including a Stroop task (to measure attentional executive control), an N‐back task (to measure working memory), and a delay discounting task (to measure decision making) to identify the brain regions affected by rs1063843 was performed. Across all three tasks, it was found that carriers of the risk allele consistently exhibited increased activation of the left DLPFC. In addition, the risk allele carriers also exhibited increased activation of the right DLPFC and the left cerebellum during the Stroop task and of the left caudate nucleus during the N‐back task. These findings helped to elucidate the role of CAMKK2 in cognitive functions and in the etiology of SCZ. Hum Brain Mapp 37:2398–2406, 2016. © 2016 Wiley Periodicals, Inc .