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141.

Background

Hepatocellular carcinoma (HCC) is a classical example of inflammation-linked cancer and is characterized by hypervascularity suggesting rich angiogenesis. Cycloxygenase-2 (COX-2) is a potent mediator of inflammation and is considered to upregulate angiogenesis. The aims of the study are (1) to analyze expression of Cox-2 mRNA, Cox-2 protein, miR-16, miR-21 and miR-101 in HCC and adjacent liver parenchyma in cirrhotic and noncirrhotic liver, (2) to investigate the relation between COX-2 expression, miR-21 expression and angiogenic factors in these tissues and (3) to investigate the association between miR-16 and miR-101 and COX-2 expression.

Methods

Tissue samples of HCC and adjacent liver parenchyma of 21 noncirrhotic livers and 20 cirrhotic livers were analyzed for COX-2 expression at the mRNA level (qRT-PCR) and at the protein level by Western blot and immunohistochemistry. Gene expression of VEGFA, VEGFR1, VEGFR2, Ang-1, Ang-2 and Tie-2 were correlated with COX-2 levels. miR-16, miR-21 and miR-101 gene expression levels were quantified in HCC tumor tissue.

Results

COX-2 mRNA and protein levels were lower in HCC as compared to adjacent liver parenchyma both in cirrhotic and noncirrhotic liver. COX-2 protein localized mainly in vascular and sinusoidal endothelial cells and in Kupffer cells. At the mRNA level but not at the protein level, COX-2 correlated with mRNA levels of angiogenic factors VEGFR1, Ang-1, and Tie2. miR-21 expression was higher in cirrhotic tissues versus noncirrhotic tissues. MiR-101 expression was lower in cirrhotic versus noncirrhotic adjacent liver parenchyma. None of the miRNAs correlelated with COX-2 expression. miR-21 correlated negatively with Tie-2 receptor in adjacent liver parenchyma.

Conclusions

In human HCC, COX-2 mRNA but not COX-2 protein levels are associated with expression levels of angiogenic factors. MiR-21 levels are not associated with angiogenic molecules. MiR-16 and miR-101 levels do not correlate with COX-2 mRNA and protein levels.  相似文献   
142.
Whon TW  Kim MS  Roh SW  Shin NR  Lee HW  Bae JW 《Journal of virology》2012,86(15):8221-8231
Airborne viruses are expected to be ubiquitous in the atmosphere but they still remain poorly understood. This study investigated the temporal and spatial dynamics of airborne viruses and their genotypic characteristics in air samples collected from three distinct land use types (a residential district [RD], a forest [FR], and an industrial complex [IC]) and from rainwater samples freshly precipitated at the RD site (RD-rain). Viral abundance exhibited a seasonal fluctuation in the range between 1.7 × 10(6) and 4.0 × 10(7) viruses m(-3), which increased from autumn to winter and decreased toward spring, but no significant spatial differences were observed. Temporal variations in viral abundance were inversely correlated with seasonal changes in temperature and absolute humidity. Metagenomic analysis of air viromes amplified by rolling-circle phi29 polymerase-based random hexamer priming indicated the dominance of plant-associated single-stranded DNA (ssDNA) geminivirus-related viruses, followed by animal-infecting circovirus-related sequences, with low numbers of nanoviruses and microphages-related genomes. Particularly, the majority of the geminivirus-related viruses were closely related to ssDNA mycoviruses that infect plant-pathogenic fungi. Phylogenetic analysis based on the replication initiator protein sequence indicated that the airborne ssDNA viruses were distantly related to known ssDNA viruses, suggesting that a high diversity of viruses were newly discovered. This research is the first to report the seasonality of airborne viruses and their genetic diversity, which enhances our understanding of viral ecology in temperate regions.  相似文献   
143.
Germline mutations that inactivate BRCA2 promote early-onset cancer with chromosome instability. Here, we report that BRCA2 regulates the spindle assembly checkpoint (SAC). Previously, we reported that BubR1 acetylation is essential for SAC activity. In this study we show that BRCA2 recruits the PCAF acetyltransferase and aids in BubR1 acetylation during mitosis. In the absence of BRCA2, BubR1 acetylation is abolished, and the level of BubR1 decreases during mitosis. Similarly, Brca2-deficient mouse embryonic fibroblasts exhibited weak SAC activity. Transgenic mice that were engineered to have interruptions in the BRCA2-BubR1 association exhibited marked decrease of BubR1 acetylation, weakened SAC activity, and aneuploidy. These transgenic mice developed spontaneous tumors at 40% penetrance. Moreover, immunohistochemical analyses of human breast cancer specimens suggested that BRCA2 mutation and BubR1 status is closely linked. Our results provide an explanation for how mutation of BRCA2 can lead to chromosome instability without apparent mutations in SAC components.  相似文献   
144.
There is scant literature about patients in the final phase of dementia. Uniform terminology and operational definition of the final phase of dementia is lacking. Furthermore, it is difficult to monitor these patients because existing assessment scales face bottom- or ceiling effects in this population. The aim of this study was to assess the prevalence and the characteristics of patients in the final phase of dementia in a group of 210 Dutch nursing home patients with dementia. Stage 7 of the Global Deterioration Scale of Reisberg et al. was used to operationally define the final phase of dementia. All patients were scored on a self-constructed assessment scale. Furthermore, treatment aspects and advance directives were registered.  相似文献   
145.
Curcumin and some of its derivatives were known as in vivo inhibitors of angiogenesis. In present study, a novel curcumin derivative, named hydrazinocurcumin (HC) was synthesized and examined for its biological activities. HC potently inhibited the proliferation of bovine aortic endothelial cells (BAECs) at a nanomolar concentration (IC(50)=520 nM) without cytotoxicity. In vivo and in vitro angiogenesis experiments showed HC as a new candidate for anti-angiogenic agent.  相似文献   
146.

Aim

The current outcome of out-of-hospital cardiac arrest (OHCA) patients in the Maastricht region was analysed with the prospect of implementing extracorporeal cardiopulmonary resuscitation (E-CPR).

Methods

A retrospective analysis of adult patients who were resuscitated for OHCA during a 24-month period was performed.

Results

195 patients (age 66 [57–75] years, 82 % male) were resuscitated for OHCA by the emergency medical services and survived to admission at the emergency department. Survival to hospital discharge was 46.2 %. Notable differences between non-survivors and survivors were observed and included: age (70 [58–79] years) vs. (63 [55–72] years, p = 0.01), chronic heart failure (18 vs. 7 %, p = 0.02), shockable rhythm (67 vs. 99 %, p < 0.01), and return of spontaneous circulation (ROSC) at departure from the site of the arrest (46 vs. 99 %, p < 0.01) and on arrival to the emergency department (43 vs. 98 %, p < 0.01), respectively. Acute coronary syndrome was diagnosed in 32 % of non-survivors vs. 59 % among survivors, p < 0.01. Therapeutic hypothermia was provided in non-survivors (20 %) vs. survivors (43 %), p < 0.01. Percutaneous coronary intervention (PCI) was performed in 14 % of non-survivors while 52 % of survivors received PCI (p < 0.01). No statistical significance was observed in terms of gender, witnessed arrest, bystander CPR, or automated external defibrillator deployed among the cohort. At hospital discharge, moderately severe neurological disability was present in six survivors.

Conclusion

These observations are compatible with the notion that a shockable rhythm, ROSC, and post-arrest care improve survival outcome. Potentially, initiating E-CPR in the resuscitation phase in patients with a shockable rhythm and no ROSC might serve as a bridge to definite treatment and improve survival outcome.  相似文献   
147.
148.
A hybrid supercapacitor with high energy and power densities is reported. It comprises a composite anode of anatase TiO2 and reduced graphene oxide and an activated carbon cathode in a non‐aqueous electrolyte. While intercalation compounds can provide high energy typically at the expense of power, the anatase TiO2 nanoparticles are able to sustain both high energy and power in the hybrid supercapacitor. At a voltage range from 1.0 to 3.0 V, 42 W h kg?1 of energy is achieved at 800 W kg?1. Even at a 4‐s charge/discharge rate, an energy density as high as 8.9 W h kg?1 can be retained. The high energy and power of this hybrid supercapacitor bridges the gap between conventional batteries with high energy and low power and supercapacitors with high power and low energy.  相似文献   
149.

Background

The objective of this study was to determine whether acute histologic chorioamnionitis is associated with adverse neonatal outcomes in late preterm infants who were born after preterm PROM.

Methodology/Principal Findings

The relationship between the presence of acute histologic chorioamnionitis and adverse neonatal outcome was examined in patients with preterm PROM who delivered singleton preterm newborns between 34 weeks and 36 6/7 weeks of gestation. Nonparametric statistics were used for data analysis. The frequency of acute histologic chorioamnionitis was 24% in patients with preterm PROM who delivered preterm newborns between 34 weeks and 36 6/7 weeks of gestation. Newborns born to mothers with histologic chorioamnionitis had significantly higher rates of adverse neonatal outcome (74% vs 51%; p<0.005) than those without histologic chorioamnionitis. This relationship remained significant after adjustment for gestational age at preterm PROM, gestational age at delivery, and exposure to antenatal corticosteroids.

Conclusions/Significance

The presence of acute histologic chorioamnionitis is associated with adverse neonatal outcome in late preterm infants born to mothers with preterm PROM.  相似文献   
150.
Repair of UV damage in plasmid DNA by human fibroblasts   总被引:1,自引:0,他引:1  
Summary Plasmid DNA from Bacillus subtilis was introduced into monolayers of human fibroblasts by means of a modification of the calcium phosphate coprecipitation technique, comprising centrifugation of the coprecipitate onto the cells and treatment with polyethyleneglycol. The amount of DNA resistant to removal from the monolayers ranged from 10% to 15% of the input DNA. By determination of the biological activity of the plasmid DNA, re-extracted after various periods following entry into the fibroblasts and subsequently used as donor for B. subtilis protoplasts, it was shown that the activity of the plasmid DNA was gradually lost. When ultraviolet light-inactivated plasmid DNA was used as donor, reactivation of the plasmid was observed, which was completed within 2 h. The dose-dependent incorporation of [14C]-thymidine suggests that DNA repair processes were involved in reactivation of the plasmid DNA.  相似文献   
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