Study on the effects of parecoxib on hypothalamus orexin neuron of cerebral infarction rats

OBJECTIVE

To explore the effect of parecoxib on cerebral infarction in rats and the regulatory mechanism on hypothalamus orexin neurons (orexin) and protein expression.

MATERIALS AND METHODS

60 SD male rats were randomly divided into sham operation group, model group and treatment group (20 rats in each group). Cerebral infarction model was established by modified Longa method. Rats in the treatment group were given parecoxib (2.5 mg kg-1) in tail by intravenous injection, while both the sham operation group and the model group were given the equal volume of sterile PBS solution in the tail vein. Continuous intervention of 72h was carried out in the three groups. Immunofluorescence staining and Western blot were used to detect the expression of orexin neurons and orexin protein in the hypothalamus of rats, respectively.

RESULTS

Immunofluorescence staining showed that the number of orexin positive cells in the model group was significantly less than that in the sham-operated group (p < 0.01). After treatment intervention, the number of orexin positive cells in the hypothalamus was significantly increased compared to that in model group (p < 0.01). Western blot analysis showed that compared with sham operation group, the expression of orexin in the hypothalamus of model group was significantly decreased (p < 0.01), whereas the expression of orexin protein was significantly elevated after parecoxib intervention (p < 0.01).

CONCLUSIONS

Parecoxib plays a therapeutic effect on cerebral infarction by up-regulating the orexin neuron.

Chemical-bond effect on epitaxial strain in perovskite sodium niobate

Epitaxial films and heterostructures of perovskite oxides attract tremendous scientific interest because of the unique phenomena therein. Especially important is the epitaxial growth of films subjected to substrate-induced misfit strain. We show here that in contrast to conventional misfit-controlled epitaxy, chemical bonds determine the crystal stability and strain in epitaxial films of sodium niobate on different cubic substrates. Strain relaxation in sodium niobate is independent of misfit magnitude and proceeds through perovskite-specific tilting of oxygen octahedra in addition to common defect formation. The observed structural relaxation evidences a major role of a large internal strain that originates from chemical bonds in the perovskite cell. The effect of chemical bonds on film strain is anticipated to also control the epitaxy of other perovskite oxides and related compounds.

73 Fatty Acid Supplementation in Culture Medium with Reduced Nutrient Concentrations Improves Bovine Blastocyst Development Compared with Standard Culture Medium

Lipids are a potent source of cellular energy and are metabolized within mitochondria via fatty acid β-oxidation, a process that also requires carnitine. Embryos metabolize lipids during pre-implantation development, but relatively little is known about the effect of fatty acid supplementation for early bovine embryogenesis in culture. The objective of this study was to evaluate the effect of lipid supplementation (via albumin) and l-carnitine (C; 5 mM) during embryo culture in a novel medium with reduced concentrations of nutrients, compared with our standard culture medium (control). Following in vitro maturation and IVF, zygotes were cultured using a serum-free sequential media system (0-72 h step 1; 72-168 h step 2). Concentrations of salts, bicarbonate, and protein [2.5 mg mL−1 fatty acid-free (FAF) or fraction V (FrV) BSA] were the same in all treatments to maintain consistent osmolarity and pH. Nutrients (glucose/fructose, citrate, lactate, pyruvate, amino acids, vitamins, and EDTA) were diluted to 6.25% of control. In addition to the control medium (100%+FAF; n = 587), experimental treatments included 6.25%+FAF+C (essentially lipid free; n = 573) and 6.25%+FrV+C (lipid rich; n = 585). Following in vitro culture (7 reps), hatching blastocysts were stained to determine inner cell mass (ICM; SOX2+) and trophectoderm (TE; CDX2+) cell numbers. Lipid content of single expanded blastocysts was determined using gas chromatography coupled to an ISQ-LT MS/MS (GC-MS). Data (mean ± SEM) were analysed by ANOVA. Embryo cleavage did not differ between treatments. Blastocyst development (per cleaved embryo) was higher (P < 0.05) after culture in lipid rich (38.3 ± 1.5%) compared with control (29.6 ± 2.2%) and lipid free (28.1 ± 3.6%). Blastocyst hatching was reduced (P < 0.05) in lipid free (1.4 ± 0.7%) but not in lipid rich (5.2 ± 1.7) compared with control (9.8 ± 2.1). However, blastocysts developed in lipid rich and lipid free had reduced cell numbers compared with control: TE, 98.7 ± 5.9 and 98.8 ± 9.1 v. 160.3 ± 9.0; ICM, 19.2 ± 2.9 and 25.2 ± 6.1 v. 43.3 ± 4.0; and total cell number, 117.9 ± 7.3 and 124.0 ± 8.7 v. 203.6 ± 10.2, respectively. Analysis by GC-MS identified 40 annotated lipids (i.e. triacylglycerols and phosphatidyl cholines) that were significantly reduced in blastocysts cultured in lipid rich compared with control. In summary, blastocyst development was significantly improved after supplementation of fatty acids and l-carnitine to a medium with reduced nutrient concentrations. The mechanism underlying this phenomenon may be related to increased lipid metabolism in the low nutrient environment. Although more embryos developed in this novel medium, these blastocysts had reduced cell numbers even though blastocyst expansion and hatching were not affected. This reduced nutrient medium may provide an experimental model in which to independently study pathways controlling cell proliferation and blastocyst development. Future studies will investigate whether embryo cell number can be rescued while maintaining improved blastocyst development.

[Application of dysphonia severity index in laryngeal reflux related voice diseases]

Objective:To discuss the validity and reliability of dysphonia severity index in evaluating the effect of diagnosis and treatment of laryngeal reflux related voice diseases. Method:54 cases of voice disease patients accompanied by laryngopharyngeal reflux from January 2016 to June 2017 in department of otorhinolaryngology of our hospital were divided into two groups according to treatment type. 32 cases in the operation group received laser surgery and standard acid suppression therapy for 6 weeks, and 22 patients in the non-operation group received standard acid suppression therapy for 6 weeks. 24 h multichannel impedance pH (MCII-pH) monitoring was carried out. The indexes of reflux symptom, reflux finding score, subjective auditory perception and objective acoustic parameters of voice were measured before and after treatment, and the dysphonia severity index was calculated and analyzed. Result:There was no significant difference in age, sex and course of disease between the two groups (P> 0.05).Compared with pre-treatment, RSI, RFS, Jitter, Shimmer, G and R in two groups decreased significantly after treatment, and MPT, DSI increased significantly (P<0.05). Before treatment, RSI, RFS, Jitter, Shimmer, G and R in the operation group were significantly higher than those in the non-operation group, and MPT, DSI were lower (P<0.05). There were no significant differences in the parameters between the two groups after treatment (P> 0.05). DSI was negatively correlated with GRBAS scoring parameters, Jitter and Shimmer, and positively correlated with RSI, RFS, and MPT (P<0.01). DSI is related to the location of the lesion (P<0.05) The incidence of anxiety was 27.27% in patients with moderate and severe sudden sensorineural hearing loss, and the incidence of depression was 25.25%. The scores of anxiety and depression were statistically significant (P<0.05). The multivariate logistic regression analysis showed that the status of anxiety and depression was accompanied by symptoms and other diseases (P<0.05). There was a significant difference between the effective group, the significant efficacy group and the cured group (P<0.05). The difference between the scores before and after treatment was compared. Differences in the ineffective group compared with the other three groups, and the cured group compared with the other three groups of anxiety, depression were statistically significant. Conclusion:DSI can be used as an objective evaluation index for the diagnosis and treatment of laryngeal reflux related voice diseases, and it is accurate and reliable.

Does thyroid dysfunction increase the risk of breast cancer? A systematic review and meta-analysis

PURPOSE

To investigate the relationship between hypothyroidism, hyperthyroidism, thyroid hormone replacement, and the risk of breast cancer.

METHODS

We searched the PubMed, Cochrane Library, EMbase, Web of Science, and China Biology Medicine (CBM) databases through June 2016 to identify researches that assessed the relationship between thyroid dysfunction and the risk of breast cancer together with the impact of thyroid hormone substitution treatment on incidence of breast cancer. Quality of evidence was assessed per outcome, using GRADE.

RESULTS

A total of 13 population-based studies including 24,808 participants were identified as eligible for this meta-analysis. A meta-analysis of 12 researches illustrated that hypothyroidism was not related to the risk for breast cancer [odds ratio (OR) = 0.83, 95% confidence interval (CI) 0.64-1.08, P = 0.162]. 10 researches illustrated that hyperthyroidism was also not related to the risk of breast cancer (OR = 1.03, 95% CI 0.83-1.30, P = 0.767). The impact of therapy was evaluated in six researches; there was no proof of a relationship between thyroid hormone substitution treatment and breast cancer with an overall OR of 0.83 (95% CI 0.57-1.21, P = 0.965).

CONCLUSIONS

Our meta-analysis illustrated that thyroid dysfunction may not be related to increased risk of breast cancer as well as the thyroid hormone substitution treatment did not reduce the incidence of breast cancer; while this study has some confounders that might weaken the results of this meta-analysis, we believe that the findings provide valuable information for stakeholders concerned with outcomes in patients with thyroid dysfunction.

[Percutaneous biopsy of the renal masses under ultrasound: a single-center 14 years experience]

OBJECTIVE

To assess the diagnostic rate, safety and clinical application of percutaneous renal masses biopsy for advanced renal cell carcinoma patients.

METHODS

In this retrospective study, we collected the data of renal masses from the patients who underwent renal masses biopsy under ultrasound from April 2001 to December 2014 in Peking University First Hospital. A total of 75 patients who were undiagnosed or diagnosed with advanced renal cell carcinoma by the imageological method were enrolled in this study. The patient and lesion characteristics such as tumor size, pathology of tumor, histologic subtype, pathological grade, biopsied location and biopsied cores were recorded and analyzed.

RESULTS

Among all the 75 patients, biopsy was diagnostic in 64 cases (85.3%) and non-diagnostic in 11 cases (14.7%). Of the 64 diagnostic biopsies, 60 were malignant, including 37 (61.7%) renal cell carcinoma (RCC), 13 (21.7%) urothelial carcinoma and 10 (16.7%) other malignant masses. Of all the RCC subjects, 24 suffered from clear cell RCC, 5 papillary RCC, 3 collecting duct carcinomas, 1 unclassified RCC and 4 unknown subtypes. The 11 non-diagnostic biopsied samplings included inflammatory, blood and extrarenal tissue and normal renal tissue. The proportion of collecting duct carcinoma in RCC was 10.8% and the proportion of squamous carcinoma in urothelial carcinoma was 23.1%, which were both higher than the previous research findings. For the male and female groups, non-diagnostic yields were 6.5% and 30.4%, respectively (P=0.022). Of all the 75 patients, 13 renal cell carcinoma patients underwent the surgical treatment and got the results of postoperative pathology. Comparing preoperative biopsy pathological diagnosis with postoperative pathological diagnosis, we found the diagnostic correct rates for benign and malignant lesions, pathological subtype and pathological grade were 100%, 81.8% and 60%, respectively. Mild macroscopic hematuria occurred in 1 case after RMB and there were no serious complications in all the cases.

CONCLUSION

Percutaneous renal masses biopsy under ultrasound with a high diagnostic rate which can define the histologic subtype of renal cell carcinoma. With targeted therapy, more and more patients whose evaluation suggests local advanced disease or metastatic tumors adopt renal tumor biopsy to define the histologic subtype, which could avoid unnecessary surgical treatment.

An effective indicator in predicting cardiovascular events: urine albumin to creatinine ratio

OBJECTIVE

To study elderly hypertensive patients with trace albuminuria (urine albumin to creatinine ratio (UACR)) and the relationship between the occurrence of new cardiovascular events, to provide a basis for early prevention in elderly patients with high blood pressure.

PATIENTS AND METHODS

A total of 3564 elderly patients with high blood pressure were enrolled in the study. Based on UACR, patients were divided into four groups (group A: 0.05-3.20 mg/g; group B:3.21-10.04 mg/g; group C: 10.05-19.33 and group D: 19.34-30.00 mg/g). All patients underwent follow-up for an average period of 3.8 years. Four groups were compared for new cardiovascular events and they were correlated with UACR.

RESULTS

Through multivariate Cox proportional hazards regression analysis, the relative risk of cardiocerebrovascular events, cerebral infarction, and acute myocardial infarction (mi), in group D was 1.74 times (p < 0.05), 1.66 times (p < 0.05), and 2.48 times (p < 0.05), respectively. UACR level in females and those with higher age, body mass index, systolic blood pressure, fasting blood glucose, TG, TC, LDL-C levels and lower HDL-C were higher. During follow-up, patients from group D with sudden cardiac death, acute myocardial infarction, cerebral hemorrhage, cerebral infarction occurrence was significantly higher than group A (χ2 = 79.3, p = 79.3) CONCLUSIONS: According to UACR level, we can perform early prevention for elderly patients with high blood pressure, thus reducing the occurrence of cerebral infarction and myocardial infarction.

Protective Effect of Edaravone Against Aβ25-35-Induced Mitochondrial Oxidative Damage in SH-SY5Y Cells

Amyloid-β (Aβ)-induced oxidative stress plays an important role in the pathogenesis of Alzheimer's disease (AD). Recent studies show that Aβ accumulation may lead to mitochondrial oxidative damage. In the present study, we investigated the protective effect of edaravone on mitochondrial damage in SH-SY5Y cells treated with Aβ25-35. SH-SY5Y cells were pre-treated with 20, 40 or 80 μM edaravone before treatment with 25 μM Aβ25-35. After 24h cell culture, cellular apoptosis, intracellular reactive oxygen species (ROS), mitochondrial membrane potential (ΔΨm), ATP levels and mitochondrial morphology were evaluated. SH-SY5Y cells exposed to Aβ25-35 had high levels of apoptosis and ROS; loss of ΔΨm, decreased ATP levels and presence of mitochondrial swelling. However, these effects were significantly inhibited by edaravone pre-treatment. These results indicate that edaravone prevents mitochondria oxidative damage caused by Aβ in SH-SY5Y cells, which suggests that it may have potential clinical application in AD therapy.

Identification of a novel HLA-A allele, HLA-A*02:505, by sequence-based typing in a patient with tuberculosis

The novel allele HLA-A*02:505 was identified in a tuberculosis patient by human leukocyte antigen sequence-based typing.

Blockade of β-catenin signaling attenuates toluene diisocyanate-induced experimental asthma

BACKGROUND

Aberrant activation of β-catenin signaling by both WNT-dependent and WNT-independent pathways has been demonstrated in asthmatic airways, which is thought to contribute critically in remodeling of the airways. Yet, the exact role of β-catenin in asthma is very poorly defined. As we have previously reported abnormal expression of β-catenin in a toluene diisocyanate (TDI)-induced asthma model, in this study, we evaluated the therapeutic efficacy of two small molecules XAV-939 and ICG-001 in TDI-asthmatic male BALB/c mice, which selectively block β-catenin-mediated transcription.

METHODS

Male BALB/c mice were sensitized and challenged with TDI to generate a chemically induced asthma model. Inhibitors of β-catenin, XAV-939, and ICG-001 were respectively given to the mice through intraperitoneally injection.

RESULTS

TDI exposure led to a significantly increased activity of β-catenin, which was then confirmed by a luciferase assay in 16HBE transfected with the TOPFlash reporter plasmid. Treatment with either XAV-939 or ICG-001 effectively inhibited activation of β-catenin and downregulated mRNA expression of β-catenin-targeted genes in TDI-asthmatic mice, paralleled by dramatically attenuated TDI-induced hyperresponsiveness and inflammation of the airway, alleviated airway goblet cell metaplasia and collagen deposition, decreased Th2 inflammation, as well as lower levels of TGFβ1, VEGF, HMGB1, and IL-1β.

CONCLUSION

The results showed that β-catenin is a principal mediator of TDI-induced asthma, proposing β-catenin as a promising therapeutic target in asthma.

Abstract P1-07-13: The mutation detection and a high throughput screening of driver mutations in PI3K/AKT pathway based on next generation sequencing

Background

The deregulation of the PI3K/AKT signaling pathway is essential to malignant cellular processes of breast cancer, including proliferation, apoptosis, and drug response. Oncogenic activating somatic mutations in the PI3K/AKT pathway are pervasive. However, it remains difficult to discriminate between driver and passenger mutations. This study was conducted to identify the landscape of genetic mutations in the PI3K/AKT pathway using Amplicon Sequencing in a Chinese population. Notably, we developed a Gateway-based mutation barcoding (GaMB) library which enables a high-throughput mutation-phenotype screen for specific vulnerable mutations that contribute to the cancer development and drug resistance.

Method

We collected 149 breast cancer specimens in a Chinese population and performed Ion Torrent Amplicon Sequencing for the key genes in PI3K/AKT pathway: PIK3CA, PIK3R1, AKT1, AKT2, AKT3, PTEN, PDK1, and the canonical tumor suppressor gene TP53, at 1000× coverage. Next, we established a high-throughput GaMB library that contained all of the PIK3CA mutations, either newly identified in Chinese population or reported in TCGA and COSMIC database, and tagged each mutations with a specific barcode. We then applied this library to functional screening processes using proliferation and drug response selection (doxorubicin or BKM-120) assays through which we screened the functional mutations with specific characteristics. The genomic DNA of the pooled surviving cells from the library, as well as the original cells before the screenings, was extracted and used for PCR amplification of the barcode regions, and then detected using Illumina Miseq sequencing to analyze the functional mutations. We then validated the cellular 2D- & 3D- proliferation abilities and the status of PI3K/AKT pathway activation in presence of identified mutations, respectively.

Result

Mutations in the PIK3CA (44%), PIK3R1 (37%), AKT3 (15%) and PTEN (12%) genes were the most prevalent. Mutations in PIK3CA were present in 65 samples (43.6%) which is similar to that reported in TCGA database. PIK3R1 (37%) was found significantly mutated, with a novel recurrent mutation, N595S, being identified in 24 patients. Similarly, AKT1 (10.1%), AKT2 (10.1%), and AKT3 (14.8%) mutations were present at a higher frequency in our population than has been reported in the TCGA and COSMIC database.

In the PIK3CA-GaMB library, our highest-ranking mutations included the previously validated deleterious mutations H1047R and E545K and several mutations of uncertain significance, including E39K, G1049R, N345I, N345K, M1043V, and H1047T. In the validation assays, we found a high phenotype-consistency of these identified mutations using these functional validation techniques. The breast cancer cells harboring identified mutations exhibit a relatively higher proliferation ability and tolerance to chemotherapy and pathway inhibitors.

Conclusion

This study identified the landscape of genetic mutations in the PI3K/AKT pathway using Amplicon Sequencing in a Chinese population. A novel developed GaMB screening platform may allow the rapid identification of significant mutations that dominate breast cancer development and drug responses during treatment.

Citation Format: Chen L, Yang L, Yao L, Hu X, Shao Z. The mutation detection and a high throughput screening of driver mutations in PI3K/AKT pathway based on next generation sequencing [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-07-13.

Abstract P2-05-37: In-situ hybridization of microRNA and support vector machines–based prognostic classifiers for breast cancer

Purpose: We plan to use a tissue microarray-based microRNA(miRNA) detection by in situ hybridization with LNA probe and support vector machine on base of data mining to construct the Prognostic model for breast cancer and triple negative breast cancer (TNBC).

Methods: Combining the BreastMark miRNA database and papers published, we chose candidate miRNAs. Then a tissue microarray-based miRNA detection in situ hybridization with LNA probe was used to detect miRNA expression in 445 breast cancer tissue. Univariate analysis with Kaplan-Meier identified independent prognostic factors, 445 patients was divided into the training set and validation set (70% VS 30%) by software R(version 3.2.3), then support vector machine on base of data mining was used to construct the Prognostic model for breast cancer and triple negative breast cancer via software R and predict.svm(e1071).

Results: 15 miRNAs were detected from 445 breast cancer tissue and univariate analysis with Kaplan-Meier identified significant prognostic miRNAs: miR-361-5p, miR-301a, miR-223, miR-421, miR-454, miR-493 were the independent prognostic factors for DFS. By using data mining technique, we combined clinical factors(stage, tumor size, lymphnode status, molecular subtype) and miRNAs mentioned above to establish the personalized predictive mathematical models SVM-BC and SVM-TNBC.

In the training set and validation set of SVM-BC model, the AUC value of ROC curve for DFS were 0.86,0.83. The total accuracy,sensitivity,specificity of SVM-BC model for DFS were 94%,73%,99% and 84%,57%,92% in the training set and validation set. The SVM-BC model can divide breast cancer patients into high-risk and low-risk groups, and 5-year survival rates for low-risk patients were higher than that for high-risk patients(96.8% VS 39.3%, p&lt;0.001).

In the training set and validation set of SVM-TNBC model, the AUC value of ROC curve for DFS were 0.84,0.86. The total accuracy,sensitivity,specificity of SVM-TNBC model for DFS were 90%,71%,97% and 84%,55%,94% in the training set and validation set. The SVM-TNBC model can divide breast cancer patients into high-risk and low-risk groups, and 5-year survival rates for low-risk patients were higher than that for high-risk patients(93.9 % VS 23.5%, p &lt;0.001).

Conclusion: The Prognostic model basing of tissue microarray-based miRNA detection in situ hybridization with LNA probe and support vector machine for prognosis can effectively predict the prognosis of breast cancer and TNBC.

Citation Format: Cao Z, Yao L, Hu X, Zhang Z, Shao Z. In-situ hybridization of microRNA and support vector machines–based prognostic classifiers for breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-05-37.

Common pattern of gray-matter abnormalities in drug-naive and medicated first-episode schizophrenia: a multimodal meta-analysis

Studies of schizophrenia at drug-naive state and on antipsychotic medication have reported a number of regions of gray-matter (GM) abnormalities but the reports have been inconsistent. The aim of this study was to conduct multimodal meta-analysis to compare the cross-sectional voxel-based morphometry studies of brain GM in antipsychotic-naive first-episode schizophrenia (AN-FES) and those with antipsychotic treatment within 1 year (AT-FES) to determine the similarities and differences in these groups. We conducted two separate meta-analyses containing 24 studies with a sample size of 801 patients and 957 healthy controls. A multimodal meta-analysis method was used to compare the findings between AN-FES and AT-FES. Meta-regression analyses were done to determine the influence of different variables including age, duration of illness, and positive and negative symptom scores. Finally, jack-knife analyses were done to test the robustness of the results. AN-FES and AT-FES showed common patterns of GM abnormalities in frontal (gyrus rectus), superior temporal, left hippocampal and insular cortex. GM in the left supramarginal gyrus and left middle temporal gyrus were found to be increased in AN-FES but decreased in AT-FES, whereas left median cingulate/paracingulate gyri and right hippocampus GM was decreased in AN-FES but increased in AT-FES. Findings suggest that both AN-FES and AT-FES share frontal, temporal and insular regions as common anatomical regions to be affected indicating these to be the primary regions of GM abnormalities in both groups.

Patients with HBV-related acute-on-chronic liver failure have increased concentrations of extracellular histones aggravating cellular damage and systemic inflammation

Acute-on-chronic liver failure (ACLF) is the most common type of liver failure and associated with grave consequences. Systemic inflammation has been linked to its pathogenesis and outcome, but the identifiable triggers are absent. Recently, extracellular histones, especially H4, have been recognized as important mediators of cell damage in various inflammatory conditions. This study aimed to investigate whether extracellular histones have clinical implications in patients with hepatitis B virus (HBV)-related ACLF. One hundred and twelve patients with HBV-related ACLF, 90 patients with chronic hepatitis B, 88 patients with HBV-related liver cirrhosis and 40 healthy volunteers were entered into this study. Plasma histone H4 levels, cytokine profile and clinical data were obtained. Besides, patient's sera were incubated overnight with human L02 hepatocytes or monocytic U937 cells in the presence or absence of antihistone H4 antibody, and cellular damage and cytokine production were evaluated. We found that plasma histone H4 levels were greatly increased in patients with ACLF as compared with chronic hepatitis B, liver cirrhosis and healthy control subjects and were significantly associated with disease severity, systemic inflammation and outcome. Notably, ACLF patients' sera incubation decreased cultured L02 cell integrity and induced profound cytokine production in the supernatant of U937 cells. Antihistone H4 antibody treatment abrogated these adverse effects, thus confirming a cause-effect relationship between extracellular histones and organ injury/dysfunction. The data support the hypothesis that the increased extracellular histone levels in ACLF patients may aggravate disease severity by inducing cellular injury and systemic inflammation. Histone-targeted therapies may have potentially interventional value in clinical practice.

Semiconducting alternating multi-block copolymers via a di-functionalized macromonomer approach

A route to fully-conjugated semiconducting block copolymers is presented and the prototype exhibits nanoscopic phase domain separation and good mobility.

[Critical roles of matrix metalloproteinases secreted by leukemic cells in the pathogenesis of central nervous system leukemia]

目的

观察白血病细胞分泌的基质金属蛋白酶（MMP）-2和MMP-9对脑微血管内皮细胞（BMVEC）紧密连接蛋白ZO-1、claudin-5、occludin表达及对血脑屏障（BBB）通透性的影响，探讨MMP-2和MMP-9在中枢神经系统白血病（CNSL）发病机制中的作用。

方法

①实时定量PCR检测SHI-1、HL-60、U937细胞MMP-2、MMP-9基因的转录水平；明胶酶谱法检测细胞培养上清中MMP-2和MMP-9蛋白表达；体外穿膜实验观察各白血病细胞株的侵袭能力。②将原代人BMVEC接种于铺有Matrigel胶和纤维黏连蛋白包被的Transwell小室系统中，建立体外BBB模型。将蛋白酶抑制剂GM6001处理或未处理的SHI-1、HL-60、U937细胞或MMP-2/MMP-9基因沉默的SHI-1细胞接种于BBB模型的Transwell小室上层与BMVEC共培养，倒置相差显微镜观察BMVEC的形态变化，激光共聚焦显微镜观察紧密连接蛋白ZO-1、claudin-5和occludin的表达，计算白血病细胞的穿膜率。

结果

①SHI-1细胞表达较高转录水平的MMP-2和MMP-9及酶活性，且侵袭能力强于HL-60、U937细胞（P< 0.01）。②与HL-60、SHI-1和U937细胞共培养后，融合致密的BMVEC之间出现间隙、细胞呈单个生长，紧密连接蛋白ZO-1、claudin-5和occludin的表达明显下调，各白血病细胞均不同程度地穿过体外BBB进入Transwell小室下层。其中SHI-1细胞对BMVEC的形态改变及3种紧密连接蛋白的下调最为明显，穿膜率最高。GM6001明显抑制白血病细胞分泌MMP-2和MMP-9，使BMVEC的形态有所恢复，同时上调ZO-1、claudin-5和occludin的表达，降低了BBB的通透性。③用siRNA分别沉默MMP-2和MMP-9基因后，SHI-1细胞分泌MMP-2和MMP-9被抑制，SHI-1细胞穿膜率较沉默前分别下降43.64％和57.30%（P<0.01），ZO-1、claudin-5和occludin表达上调。

结论

白血病细胞株分泌的MMP-2和MMP-9能通过降解BMVEC紧密连接蛋白ZO-1、claudin-5和occludin而破坏BBB。

Childhood obesity patterns and relation to middle-age sleep apnoea risk: the Bogalusa Heart Study

BACKGROUND

Obese adults have a higher risk of obstructive sleep apnoea (OSA); however, the relationship between childhood obesity and adult OSA risk is unclear. Objectives This study aimed to examine overweight/obesity (OW) in childhood and risk of OSA in middle age.

METHODS

Childhood OW status was classified as never OW, weight cycling, persistent OW and incident OW. After 35 years of follow-up, high risk for OSA was determined by a positive score in ≥2 domains on the Berlin Questionnaire with obesity removed from scoring.

RESULTS

At initial assessment, mean (SD) age was 9.9 (2.9) years, and 23.9% were OW. Overall, 25.7% had scores indicating a high risk for OSA. Compared with participants who were never OW, those with persistent OW and incident OW were 1.36 (95%CI: 1.04-1.77) and 1.47 (1.11-1.96) times more likely to be high risk for OSA, after adjustment for multiple risk factors and adult OW status. Participants with an OW duration of 1-4 years, 5-8 years, and 8+ years were 0.96 (0.44-2.09), 1.20 (0.70-2.04) and 1.52 (1.22-1.90) times more likely to be high risk for OSA compared with those who were never OW (P for trend: 0.0002).

CONCLUSIONS

These results suggest that childhood OW is associated with a high risk of OSA in middle age.

Antisense locked nucleic acids targeting agrA inhibit quorum sensing and pathogenesis of community-associated methicillin-resistant Staphylococcus aureus

AIM

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is commonly associated with nonnosocomial skin and soft tissue infections due to its virulence, which is mainly controlled by the accessory gene regulator (agr) quorum sensing (QS) system. In this study (KFF)₃ K peptide-conjugated locked nucleic acids (PLNAs) targeting agrA mRNA were developed to inhibit agr activity and arrest the pathogenicity of CA-MRSA.

METHODS AND RESULTS

Two PLNAs were designed, and synthesized, after predicting the secondary structure of agrA mRNA. The influence on bacterial growth was tested using a growth curve assay. RT-qPCR, haemolysis assay, lactate dehydrogenase release assay and chemotaxis assay were used to evaluate the effects of the PLNAs on inhibiting agr QS. A mouse skin infection model was employed to test the protective effect of the PLNAs in vivo. None of the PLNAs were found to be bacteriostatic or bactericidal in vitro. However, one PLNA, PLNA34, showed strong ability to suppress expression of agrA and the effector molecule RNAIII in USA300 LAC strain. Furthermore, PLNA34 inhibited the expression of virulence genes that are upregulated by agr, including hla, psmα, psmβ and pvl. The haemolytic activity of the supernatants from PLNA34-treated bacteria was also dramatically reduced, as well as the capacity to lyse and recruit neutrophils. Moreover, PLNA34 showed high levels of protection in the CA-MRSA mouse skin infection model.

CONCLUSIONS

The anti-agrA PLNA34 can effectively inhibit the agr QS and suppress CA-MRSA pathogenicity.

SIGNIFICANCE AND IMPACT OF THE STUDY

agrA is a promising target for the development of antisense oligonucleotides to block agr QS.

Cytogenetic evaluation of cataract patients occupationally exposed to ionizing radiation in northeast China

Long-term radiation exposure is hazardous to health; late-onset effects of exposure to ionizing radiation (IR) pose risks to the lens, and are associated with other non-cancerous diseases. Individuals occupationally exposed to low-dose IR are prone to developing eye cataracts. Cytogenetic evaluations suggest that IR is associated with chromosomal aberrations in occupationally exposed individuals. However, data regarding the association between chromosomal aberrations in cataract patients and occupational exposure to IR is scarce. Therefore, we aimed to report the characteristics of chromosomal aberrations in cataract patients from a Chinese population, occupationally exposed to IR. We found that the average age and frequency of numerical chromosomal aberrations were significantly lower in the exposed patients as compared with that in the non-exposed patients. In addition, the frequencies of dicentric and acentric chromosomes were significantly higher in the exposed patients as compared with those in the non-exposed patients. Therefore, chronic occupational exposure to IR affects cataract development in the Chinese population. The age of cataract patients exposed to IR was significantly lower than the age of cataract onset in normal individuals. Based on this study, we suggest that there is an urgent need for improved radiation safety and eye protection in individuals exposed to IR in the work place.