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141.
142.
Kishore Viswanathan Sophia N. Ononye Harold D. Cooper M. Kyle Hadden Amy C. Anderson Dennis L. Wright 《Bioorganic & medicinal chemistry letters》2012,22(22):6919-6922
Naturally occurring furanosteroids such as viridin and wortmannin have long been known as potent inhibitors of the lipid kinase PI-3K. We have been interested in directly accessing analogs of these complex natural products from abundant steroid feedstock materials. In this communication, we describe the synthesis of viridin/wortmannin hybrid molecules from readily available building blocks that function as PI-3K inhibitors and maintain their electrophilic properties. The compounds also show anti-proliferative effects against a breast cancer line. 相似文献
143.
Yang HP Zuna RE Schiffman M Walker JL Sherman ME Landrum LM Moxley K Gold MA Dunn ST Allen RA Zhang R Long R Wang SS Wentzensen N 《PloS one》2012,7(1):e29051
Objective
Cervical intraepithelial neoplasia grade 3 (CIN3), the immediate cervical cancer precursor, is a target of cervical cancer prevention. However, less than half of CIN3s will progress to cancer. Routine treatment of all CIN3s and the majority of CIN2s may lead to overtreatment of many lesions that would not progress. To improve our understanding of CIN3 natural history, we performed a detailed characterization of CIN3 heterogeneity in a large referral population in the US.Methods
We examined 309 CIN3 cases in the SUCCEED, a large population-based study of women with abnormal cervical cancer screening results. Histology information for 12 individual loop electrosurgical excision procedure (LEEP) segments was evaluated for each woman. We performed case-case comparisons of CIN3s to analyze determinants of heterogeneity and screening test performance.Results
CIN3 cases varied substantially by size (1–10 LEEP segments) and by presentation with concomitant CIN2 and CIN1. All grades of CINs were equally distributed over the cervical surface. In half of the women, CIN3 lesions were found as multiple distinct lesions on the cervix. Women with large and solitary CIN3 lesions were more likely to be older, have longer sexual activity span, and have fewer multiple high risk HPV infections. Screening frequency, but not HPV16 positivity, was an important predictor of CIN3 size. Large CIN3 lesions were also characterized by high-grade clinical test results.Conclusions
We demonstrate substantial heterogeneity in clinical and pathological presentation of CIN3 in a US population. Time since sexual debut and participation in screening were predictors of CIN3 size. We did not observe a preferential site of CIN3 on the cervical surface that could serve as a target for cervical biopsy. Cervical cancer screening procedures were more likely to detect larger CIN3s, suggesting that CIN3s detected by multiple independent diagnostic tests may represent cases with increased risk of invasion. 相似文献144.
Background
In the early stages of Pandemic (H1N1) 2009, border control measures were taken by quarantine stations to block the entry of infected individuals into Japan and community containment measures were implemented to prevent the spreading. The objectives of this study were to describe these measures and the characteristics of infected individuals, and to assess the measures'' effectiveness.Methodology/Principal Findings
Border control and community containment measures implemented from April to June (Period I: April 28–May 21, Period II: May 22–June 18) 2009 were described. Number of individuals identified and disease characteristics were analyzed. For entry screening, a health declaration form and an infrared thermoscanner were used to detect symptomatic passengers. Passengers indicated for the rapid influenza test underwent the test followed by RT-PCR. Patients positive for H1N1 were isolated, and close contacts were quarantined. Entry cards were handed out to all asymptomatic passengers informing them about how to contact a health center in case they developed symptoms. Nine individuals were identified by entry screening and 1 during quarantine to have Pandemic (H1N1) 2009. Health monitoring by health centers was performed in period I for passengers arriving from affected countries and in period II for those who had come into contact with the individuals identified by entry screening. Health monitoring identified 3 infected individuals among 129,546 in Period I and 5 among 746 in Period II. Enhanced surveillance, which included mandatory reporting of details of the infected individuals, identified 812 individuals, 141 (18%) of whom had a history of international travel. Twenty-four of these 141 passengers picked up by enhanced surveillance had been developing symptoms on entry and were missed at screening.Conclusion/Significance
Symptomatic passengers were detected by the various entry screening measures put in place. Enhanced surveillance provided data for the improvement of public health measures in future pandemics. 相似文献145.
Yin‐Quan Chen Pei‐lun Chou Chen‐Yu Cheng Chia‐Chun Chiang Ming‐Tzo Wei Chin‐Ting Chuang Yi‐Lin Sophia Chen Arthur Chiou 《Journal of biophotonics》2012,5(10):777-784
The viscoelastic properties of synovial fluid (SF) are critical to its functions of lubrication and shock‐absorption of joints in human body; a change in the viscoelastic properties, even of only a few percents, is often concomitant with arthritis. In this work, the elastic modulus G ′(f) and the viscous modulus G ′′(f) of SF from patients suffering from three kinds of joint diseases, namely, osteoarthritis (OA), rheumatoid arthritis (RA), and gouty arthritis (GA), were determined as a function of frequency “f ” (in the low frequency range from f ~ 0.1 to 10 Hz) by Diffusing Wave Spectroscopy (DWS) and correlated with the white blood cell (WBC) count. A strong correlation was observed, showing a higher WBC count corresponding to lower elastic and viscous moduli, G ′ and G ′′; further details depend on inflammatory vs. non‐inflammatory, and on the severity of inflammation. Different types of arthritis lead to different degrees of decreasing viscoelasticity. Identical measurements were carried out with a commercial visco‐supplementation (or artificial SF) to serve as reference. In general, the reduction in both G ′ and G ′′ was most severe in the case of GA and least severe in the case of OA. Besides, in all cases, the reduction in G ′ was more prominent than the reduction in G ′′, indicating that in general, the deterioration in the elasticity of SF by inflammation is more severe than that in the viscosity. This simple method for quantitative physical characterization of synovial fluid may serve as a useful complementary metric to the conventional biochemical analysis in clinical diagnosis of arthritis. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
146.
V Gallo JP Mackenbach M Ezzati G Menvielle AE Kunst S Rohrmann R Kaaks B Teucher H Boeing MM Bergmann A Tjønneland SO Dalton K Overvad ML Redondo A Agudo A Daponte L Arriola C Navarro AB Gurrea KT Khaw N Wareham T Key A Naska A Trichopoulou D Trichopoulos G Masala S Panico P Contiero R Tumino HB Bueno-de-Mesquita PD Siersema PP Peeters S Zackrisson M Almquist S Eriksson G Hallmans G Skeie T Braaten E Lund AK Illner T Mouw E Riboli P Vineis 《PloS one》2012,7(7):e39013
Background
Socio-economic inequalities in mortality are observed at the country level in both North America and Europe. The purpose of this work is to investigate the contribution of specific risk factors to social inequalities in cause-specific mortality using a large multi-country cohort of Europeans.Methods
A total of 3,456,689 person/years follow-up of the European Prospective Investigation into Cancer and Nutrition (EPIC) was analysed. Educational level of subjects coming from 9 European countries was recorded as proxy for socio-economic status (SES). Cox proportional hazard model''s with a step-wise inclusion of explanatory variables were used to explore the association between SES and mortality; a Relative Index of Inequality (RII) was calculated as measure of relative inequality.Results
Total mortality among men with the highest education level is reduced by 43% compared to men with the lowest (HR 0.57, 95% C.I. 0.52–0.61); among women by 29% (HR 0.71, 95% C.I. 0.64–0.78). The risk reduction was attenuated by 7% in men and 3% in women by the introduction of smoking and to a lesser extent (2% in men and 3% in women) by introducing body mass index and additional explanatory variables (alcohol consumption, leisure physical activity, fruit and vegetable intake) (3% in men and 5% in women). Social inequalities were highly statistically significant for all causes of death examined in men. In women, social inequalities were less strong, but statistically significant for all causes of death except for cancer-related mortality and injuries.Discussion
In this European study, substantial social inequalities in mortality among European men and women which cannot be fully explained away by accounting for known common risk factors for chronic diseases are reported. 相似文献147.
148.
149.
Chamakou AC Dede E Moutafi A Thanopoulos V Chryssanthopoulos S Loukopoulou S Pitsavos C Stefanadis C Davos CH 《Cytokine》2012,57(1):130-135
Introduction
Inflammation and neurohormonal activation are considered to be involved in the development of earlier and/or later complications in congenital heart disease patients, even after a successful repair of the lesion. It is not yet clarified what is the role of the therapeutic interventions in the occurrence of such a response and how it could be associated with possible postoperative complications.Aim
We sought to assess the inflammatory and neurohormonal response to transcatheter closure of secundum type atrial septal defects (ASD) over a six-month follow-up period. We also evaluated the association between the respective markers and catheterization data as well as echocardiographic measurements.Methods
Plasma concentrations of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), N-terminal-proatrial natriuretic peptide (NT-proANP) and N-terminal-probrain natriuretic peptide (NT-proBNP) were assessed and echocardiographic measurements were performed in twenty-eight patients with atrial septal defect prior to, and at the first, second and sixth months post transcatheter closure. Thirty-three age-matched healthy volunteers were also enrolled.Results
IL-6 plasma levels, although higher preoperatively, [physical logarithm (ln) IL-6: 3.37 ± 0.66 vs 2.92 ± 0.44 pg/ml, p = 0.015], reached control levels postoperatively, at the end of the third month, whereas TNF-α and IL-10 were not influenced by the procedure. NT-proANP levels were elevated preoperatively compared to the control group (ln NT-proANP 3.78 ± 0.572 vs 3.48 ± 0.30, p = 0.031), with a further significant increase during the 1st month (ln NT-proANP 3.78 ± 0.572 vs 4.2 ± 0.42, p = 0.006), following the pattern of the left atrial volume enlargement, and remained high even 6 months after the procedure .On the other hand, the initially normal concentrations of NT-proBNP, after a transient significant increase during the first month postoperatively (ln NT-proBNP 3.56 ± 0.94 vs 4.58 ± 0.91, p < 0.0001) returned to the controls’ levels at the end of the third month. Preoperative concentrations of NT-proANP positively correlated with NT-proBNP concentrations and pulmonary to systemic flow ratio (Qp/Qs).Conclusions
Transcatheter closure could improve, on a mid- term basis, the inflammatory process but natriuretic peptides’ secretion continues in parallel with left atrial volume increase. Further follow up is required to determine the long-term progress of the inflammatory and neurohormonal response to the procedure. 相似文献150.
Hotta T Kong Z Ho CM Zeng CJ Horio T Fong S Vuong T Lee YR Liu B 《The Plant cell》2012,24(4):1494-1509
Plant cells assemble the bipolar spindle and phragmoplast microtubule (MT) arrays in the absence of the centrosome structure. Our recent findings in Arabidopsis thaliana indicated that AUGMIN subunit3 (AUG3), a homolog of animal dim γ-tubulin 3, plays a critical role in γ-tubulin-dependent MT nucleation and amplification during mitosis. Here, we report the isolation of the entire plant augmin complex that contains eight subunits. Among them, AUG1 to AUG6 share low sequence similarity with their animal counterparts, but AUG7 and AUG8 share homology only with proteins of plant origin. Genetic analyses indicate that the AUG1, AUG2, AUG4, and AUG5 genes are essential, as stable mutations in these genes could only be transmitted to heterozygous plants. The sterile aug7-1 homozygous mutant in which AUG7 expression is significantly reduced exhibited pleiotropic phenotypes of seriously retarded vegetative and reproductive growth. The aug7-1 mutation caused delocalization of γ-tubulin in the mitotic spindle and phragmoplast. Consequently, spindles were abnormally elongated, and their poles failed to converge, as MTs were splayed to discrete positions rendering deformed arrays. In addition, the mutant phragmoplasts often had disorganized MT bundles with uneven edges. We conclude that assembly of MT arrays during plant mitosis depends on the augmin complex, which includes two plant-specific subunits. 相似文献