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91.

Background

The post-resuscitation phase after out-of-hospital cardiac arrest (OHCA) is characterised by a systemic inflammatory response (e.g., severe sepsis), for which the immature granulocyte count is a diagnostic marker. In this study we evaluated the prognostic significance of the delta neutrophil index (DNI), which is the difference in leukocyte subfractions as assessed by an automated blood cell analyser, for early mortality after OHCA.

Materials and Methods

OHCA records from the emergency department cardiac arrest registry were retrospectively analysed. Patients who survived at least 24 h after return of spontaneous circulation were included in the analysis. We evaluated mortality and cerebral performance category scores at 30 days.

Results

A total of 83 patients with OHCA were included in the study. Our results showed that DNI >8.4% on day 1 (hazard ratio [HR], 3.227; 95% CI, 1.485–6.967; p = 0.001) and DNI >10.5% on day 2 (HR, 3.292; 95% CI, 1.662–6.519; p<0.001) were associated with increased 30-day mortality in patients with OHCA. Additionally, DNI >8.4% on day 1 (HR, 2.718; 95% CI, 1.508–4.899; p<0.001) and DNI >10.5% on day 2 (HR, 1.709; 95% CI, 1.051–2.778; p = 0.02) were associated with worse neurologic outcomes 30 days after OHCA.

Conclusion

A higher DNI is a promising prognostic marker for 30-day mortality and neurologic outcomes after OHCA. Our findings indicate that patients with elevated DNI values after OHCA might be closely monitored so that appropriate treatment strategies can be implemented.  相似文献   
92.
The efficacy of entecavir (ETV) and tenofovir (TDF) for the treatment of nucleos(t)ide analogue (NA)-experienced chronic hepatitis B (CHB) patients has been little studied. Here, we compare the efficacy of both ETV and TDF in NA-experienced CHB patients without detectable genotypic resistance. This retrospective cohort study included consecutive NA-experienced patients who had neither current nor previous genotypic resistance and had received ETV or TDF for at least 6 months. Overall, 202 patients (146 patients in the ETV group and 56 in the TDF group) were analyzed. The cumulative probabilities of complete virologic suppression (CVS) at month 12 were 76.1% in the ETV group and 95.0% in the TDF group (P<0.001), respectively. The TDF-treated group achieved CVS more rapidly than the ETV group for both Hepatitis B e antigen (HBeAg)-negative and -positive patients (P = 0.006 and < 0.001, respectively), and for those with both low (< 2,000 IU/mL) and high (≥ 2,000 IU/mL) HBV DNA levels (P = 0.01 and 0.002, respectively). TDF group had an increased probability of achieving CVS (hazard ratio, 2.242; 95% confidence interval, 1.587–3.165; P = 0.001), after adjustment for HBV DNA level, the presence of HBeAg, and a history of CVS during prior treatment. During the treatment period, 23 patients (15.8%) in the ETV group developed virologic breakthrough, compared to none in the TDF group. The cumulative probabilities of developing virologic breakthrough and ETV-resistance at month 24 were 9.7% and 5.3%, respectively. In conclusion, TDF is preferable to ETV for achieving CVS in NA-experienced CHB patients without genotypic resistance.  相似文献   
93.

Objectives

To assess the malignancy rates of thyroid nodules repeatedly classified as Bethesda category III on fine needle aspiration (FNA), and to suggest management guidelines for these lesions.

Methods

This is a retrospective study that included 395 thyroid nodules categorized as Bethesda III undergone either surgery or ultrasound (US) follow-up. There were 67 nodules classified a second time as Bethesda category III on repeat FNA. We compared malignancy rates, clinicopathologic and ultrasonographic characteristics between direct surgery and repeat FNA groups and between the initial and repeat Bethesda category III groups, each. And in the repeat Bethesda III group, clinicopathologic and US variables were compared between benign and malignant nodules.

Results

Incidence of concurrent cancer, underlying thyroiditis and positive BRAF mutation were significantly higher in 142 nodules with direct surgery than 243 nodules with repeat FNA (p < 0.05). Of the 395 nodules with Bethesda category III cytology on initial FNA, the malignancy rate was 59.5%. In 67 nodules with repeat Bethesda III classification, however, the malignancy rate was 73.1% (p < 0.05). However, none of the variables were significantly different between the initial Bethesda category III group and the repeat Bethesda category III group (p > 0.05). In the repeat Bethesda category III group, solid consistency, irregular/microlobulated margins, nonparallel shape, and number of suspicious findings or “suspicious malignant” US assessments were associated with a high malignancy rate (p < 0.05). On multivariate logistic regression analysis, the factor associated with malignancy in the repeat Bethesda category III group was irregular/microlobulated margin (odds ratio = 15.576; 95% CI, 2.097–115.6804, p = 0.007) with a sensitivity, specificity, positive and negative predictive values, and accuracy of 81.6%, 83.3%, 93.0%, 62.5% and 82.1%, respectively.

Conclusion

Thyroid nodules with repeated Bethesda category III classification and irregular/microlobulated margins on US are at increased risk of malignancy, and operative management should be considered as opposed to repeat FNA.  相似文献   
94.
Park SE  Song JD  Kim KM  Park YM  Kim ND  Yoo YH  Park YC 《FEBS letters》2007,581(2):180-186
The diphenyleneiodonium (DPI) is widely used as an inhibitor of flavoenzymes, particularly NADPH oxidase. In this study, we investigated the effect of DPI on the apoptosis of human RPE cells. DPI treatment in ARPE-19 cells evoked a dose- and time-dependent growth inhibition, and also induced DNA fragmentation and protein content of the proapoptotic factor Bax. In addition, DPI significantly induced the expression and phosphorylation of p53, which induces proapoptotic genes in response to DNA damage or irreparable cell cycle arrest. ROS have been implicated as a key factor in the activation of p53 by many chemotherapeutic drugs. Recent data on the regulation of intracellular ROS by DPI are controversial. Therefore, we analyzed whether DPI could contribute to the generation of intracellular ROS. Although there was increase in ROS level from cells treated for 24h with DPI, it was not detectable at early time points, required to induce p53 expression. And DPI-induced p53 expression was not affected by the ROS scavenger NAC. We conclude that DPI induces the expression of p53 by ROS-independent mechanism in ARPE-19 cells, and renders cells sensitive to drug-induced apoptosis by induction of p53 expression.  相似文献   
95.
The ADP-ribose (ADPR) pyrophosphatase (ADPRase) NUDT5, a member of a superfamily of Nudix hydrolases, hydrolyzes ADP-ribose (ADPR) to AMP and ribose 5'-phosphate. Nitric oxide (NO) enhances nonenzymatic ADP-ribosylation of proteins such as beta-actin and glyceraldehydes 3-phosphate dehydrogenase in the presence of free ADPR, suggesting a possibility that NUDT5 could also be ADP-ribosylated by its substrate, ADPR. Here, we show that NO stimulates nonenzymatic ADP-ribosylation of NUDT5 using ADP-ribose and consequently activates its ADPRase activity. We found that ADPRase activity in J774 macrophage cells is increased by the treatment with SNP, an exogenous NO generator or TNF-alpha/IFN-gamma, endogenous NO inducers. Anti-NUDT5 antibody pulled down most of the ADPRase activity increased by NO, indicating that the ADPRase regulated by NO is NUDT5. Using recombinant human NUDT5, we also demonstrated that the increase of ADPRase activity is mediated via ADP-ribosylation at cysteine residue(s) in the presence of reductant. This result suggests that NO activates NUDT5 through ADP-ribosylation at cysteine residues of the enzyme in macrophages.  相似文献   
96.
In order to obtain information regarding the design of selective DPP4 inhibitors, a 3D-QSAR study was conducted using DPP4, DPP8, and DPP9 inhibitors including newly synthesized six- and seven-membered cyclic hydrazine derivatives (KR64300, KR64301), which were evaluated in vitro for their inhibition of DPP4, DPP8, and DPP9. In this study, a highly predictive CoMFA model based on the fast-docking for DPP4, DPP8, and DPP9 inhibitors was obtained. This reliable model showed leave-one-out cross-validation q(2) and conventional r(2) values of 0.68 and 0.96 for the DPP4 inhibitors, 0.58 and 0.98 for the DPP8 inhibitors, and 0.68 and 0.97 for the DPP9 inhibitors, respectively. The validation of the CoMFA model was confirmed by the compounds in the test set, including the synthesized six- and seven-membered cyclic hydrazines. According to this study, to obtain selective DPP4 inhibitors compared to their isozymes, the interaction of the inhibitors with the S3 site and S1' site in DPP4 must be considered. The proposed newly synthesized compounds, KR64300 and KR64301, interact well with the sites mentioned above, showing excellent selectivity.  相似文献   
97.
Kim JH  Lee KH  Yoo DH  Kang D  Cho SH  Hong YC 《Mutation research》2007,629(1):32-39
Inflammation is known to be an important underlying condition in the development of a variety of diseases. To investigate whether blood lead induces inflammatory reactions in non-occupationally exposed adults and the effects of genetic susceptibility associated with GSTM1 and TNF-alpha gene polymorphisms on this inflammatory response, we measured blood lead levels in 300 healthy university students. Total serum TNF-alpha and IL-6 levels and WBC counts were determined to evaluate the inflammatory response. Allelic loss of GSTM1 and the TNF-alpha-308 G>A polymorphism were determined by PCR and RFLP. Positive relations between blood lead and three inflammation biomarkers were shown in male subjects with blood lead > or =2.51microg/dl (median value) (TNF-alpha, p=0.015; IL-6, p=0.082; and WBC, p=0.044). However, subgroup analysis by genotype showed an effect of blood lead on the three biomarkers only in individuals with the GSTM1 null (TNF-alpha, p=0.020; IL-6, p=0.096; and WBC, p=0.017) or TNF-alpha GG (TNF-alpha, p=0.017; IL-6, p=0.088; and WBC, p=0.095) genotype, and not in individuals with GSTM1 present (all three inflammatory biomarkers, p>0.1) or the TNF-alpha GA or AA (all three biomarkers, p>0.1) genotype. These results suggest that blood lead affects the inflammatory response and that GSTM1 and TNF-alpha gene polymorphisms are genetic factors associated with lead-induced inflammatory response.  相似文献   
98.
Bacterial lipopolysaccharide (LPS) is a potent stimulator of bone resorption in periodontitis. Co-culture systems of mouse calvaria-derived osteoblasts and bone marrow-derived preosteoclasts were used as an in vitro osteoclast differentiation. This study revealed that co-cultures using ddY or ICR mouse strain responded differently to LPS while responded equally to 1alpha,25(OH)2D3. Thus, the different response to LPS indicates dissimilarity of two mouse stains in their capacity for generating osteoclasts while the two mouse strains share the similarity in response to 1alpha,25(OH)2D3. To identify which cells between osteoblasts and preosteoclasts in the co-culture are responsible for the dissimilarity, the reciprocal co-cultures were performed between ddY and ICR mouse strains. The treatment of 1,25(OH)2D3 to ddY/ICR (osteoblasts from ddY/preosteoclasts from ICR) and ICR/ddY reciprocal co-cultures also showed the similarity. In case of LPS treatment, the results of ddY/ICR were similar to ddY/ddY and the results of the other reciprocal co-culture, ICR/ddY combination, were consistent with those of ICR/ICR. It suggests that the dissimilarity between the two mouse strains may resident in osteoblasts but not in preosteoclasts. Therefore, the osteoblast is responsible for mouse strain-dependent osteoclastogenesis in response to LPS. Although mouse models will continue to provide insights into molecular mechanisms of osteoclastogenesis, caution should be exercised when using different mouse strains, especially ddY and ICR strains as models for osteoclast differentiation.  相似文献   
99.
100.
Ionic Polymer-Metal Composite (IPMC) can work as an actuator by applying a few voltages.A thick IPMC actuator,whereNafion-117 membrane was synthesized with polypyrrole/alumina composite filler,was analyzed to verify the equivalent beamand equivalent bimorph beam models.The blocking force and tip displacement of the IPMC actuator were measured with a DCpower supply and Young’s modulus of the IPMC strip was measured by bending and tensile tests respectively.The calculatedmaximum tip displacement and the Young’s modulus by the equivalent beam model were almost identical to the correspondingmeasured data.Finite element analysis with thermal analogy technique was utilized in the equivalent bimorph beam model tonumerically reproduce the force-displacement relationship of the IPMC actuator.The results by the equivalent bimorph beammodel agreed well with the force-displacement relationship acquired by the measured data.It is confirmed that the equivalentbeam and equivalent bimorph beam models are practically and effectively suitable for predicting the tip displacement,blockingforce and Young’s modulus of IPMC actuators with different thickness and different composite of ionic polymer membrane.  相似文献   
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