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1.
Background
Impact factor (IF) is a commonly used surrogate for assessing the scientific quality of journals and articles. There is growing discontent in the medical community with the use of this quality assessment tool because of its many inherent limitations. To help address such concerns, Eigenfactor (ES) and Article Influence scores (AIS) have been devised to assess scientific impact of journals. The principal aim was to compare the temporal trends in IF, ES, and AIS on the rank order of leading medical journals over time.Methods
The 2001 to 2008 IF, ES, AIS, and number of citable items (CI) of 35 leading medical journals were collected from the Institute of Scientific Information (ISI) and the http://www.eigenfactor.org databases. The journals were ranked based on the published 2008 ES, AIS, and IF scores. Temporal score trends and variations were analyzed.Results
In general, the AIS and IF values provided similar rank orders. Using ES values resulted in large changes in the rank orders with higher ranking being assigned to journals that publish a large volume of articles. Since 2001, the IF and AIS of most journals increased significantly; however the ES increased in only 51% of the journals in the analysis. Conversely, 26% of journals experienced a downward trend in their ES, while the rest experienced no significant changes (23%). This discordance between temporal trends in IF and ES was largely driven by temporal changes in the number of CI published by the journals.Conclusion
The rank order of medical journals changes depending on whether IF, AIS or ES is used. All of these metrics are sensitive to the number of citable items published by journals. Consumers should thus consider all of these metrics rather than just IF alone in assessing the influence and importance of medical journals in their respective disciplines. 相似文献2.
Background
The number of retracted scientific publications has risen sharply, but it is unclear whether this reflects an increase in publication of flawed articles or an increase in the rate at which flawed articles are withdrawn.Methods and Findings
We examined the interval between publication and retraction for 2,047 retracted articles indexed in PubMed. Time-to-retraction (from publication of article to publication of retraction) averaged 32.91 months. Among 714 retracted articles published in or before 2002, retraction required 49.82 months; among 1,333 retracted articles published after 2002, retraction required 23.82 months (p<0.0001). This suggests that journals are retracting papers more quickly than in the past, although recent articles requiring retraction may not have been recognized yet. To test the hypothesis that time-to-retraction is shorter for articles that receive careful scrutiny, time-to-retraction was correlated with journal impact factor (IF). Time-to-retraction was significantly shorter for high-IF journals, but only ∼1% of the variance in time-to-retraction was explained by increased scrutiny. The first article retracted for plagiarism was published in 1979 and the first for duplicate publication in 1990, showing that articles are now retracted for reasons not cited in the past. The proportional impact of authors with multiple retractions was greater in 1972–1992 than in the current era (p<0.001). From 1972–1992, 46.0% of retracted papers were written by authors with a single retraction; from 1993 to 2012, 63.1% of retracted papers were written by single-retraction authors (p<0.001).Conclusions
The increase in retracted articles appears to reflect changes in the behavior of both authors and institutions. Lower barriers to publication of flawed articles are seen in the increase in number and proportion of retractions by authors with a single retraction. Lower barriers to retraction are apparent in an increase in retraction for “new” offenses such as plagiarism and a decrease in the time-to-retraction of flawed work. 相似文献3.
Background
An important attribute of the traditional impact factor was the controversial 2-year citation window. So far, several scholars have proposed using different citation time windows for evaluating journals. However, there is no confirmation whether a longer citation time window would be better. How did the journal evaluation effects of 3IF, 4IF, and 6IF comparing with 2IF and 5IF? In order to understand these questions, we made a comparative study of impact factors with different citation time windows with the peer-reviewed scores of ophthalmologic journals indexed by Science Citation Index Expanded (SCIE) database.Methods
The peer-reviewed scores of 28 ophthalmologic journals were obtained through a self-designed survey questionnaire. Impact factors with different citation time windows (including 2IF, 3IF, 4IF, 5IF, and 6IF) of 28 ophthalmologic journals were computed and compared in accordance with each impact factor’s definition and formula, using the citation analysis function of the Web of Science (WoS) database. An analysis of the correlation between impact factors with different citation time windows and peer-reviewed scores was carried out.Results
Although impact factor values with different citation time windows were different, there was a high level of correlation between them when it came to evaluating journals. In the current study, for ophthalmologic journals’ impact factors with different time windows in 2013, 3IF and 4IF seemed the ideal ranges for comparison, when assessed in relation to peer-reviewed scores. In addition, the 3-year and 4-year windows were quite consistent with the cited peak age of documents published by ophthalmologic journals.Research Limitations
Our study is based on ophthalmology journals and we only analyze the impact factors with different citation time window in 2013, so it has yet to be ascertained whether other disciplines (especially those with a later cited peak) or other years would follow the same or similar patterns.Originality/ Value
We designed the survey questionnaire ourselves, specifically to assess the real influence of journals. We used peer-reviewed scores to judge the journal evaluation effect of impact factors with different citation time windows. The main purpose of this study was to help researchers better understand the role of impact factors with different citation time windows in journal evaluation. 相似文献4.
Ying Zheng Aiguo Ma Qiuzhen Wang Xiuxia Han Jing Cai Evert G. Schouten Frans J. Kok Yunchun Li 《PloS one》2013,8(11)
Background
Pulmonary tuberculosis (TB) patients often suffer from anorexia and poor nutrition, causing weight loss. The peptide hormones leptin and its counterpart ghrelin, acting in the regulation of food intake and fat utilization, play an important role in nutritional balance. This study aimed to investigate the association of blood concentrations of leptin, ghrelin and inflammatory cytokines with body mass index (BMI) in TB patients with and without type 2 diabetes mellitus (T2DM).Methods
BMI, biochemical parameters and plasma levels of leptin, ghrelin and inflammatory cytokines were measured before the start of treatment in 27 incident TB patients with T2DM, 21 TB patients and 23 healthy subjects enrolled in this study.Results
The levels of leptin were significantly higher in TB patients (35.2±19.1 ng/ml) than TB+T2DM (12.6±6.1 ng/ml) and control (16.1±11.1 ng/ml) groups. The level of ghrelin was significantly lower in TB (119.9±46.1 pg/ml) and non-significantly lower in TB+T2DM (127.7±38.6 pg/ml) groups than control (191.6±86.5 pg/ml) group. The levels of TNF-α were higher, while IFN-γ and IL-6 levels were lower in patients than in the control group. Leptin showed a negative correlation with BMI in TB (r=-0.622, p<0.05) and TB+T2DM (r= -0.654, p<0.05) groups, but a positive correlation with BMI in the control group (r=0.521, p<0.05). Contrary ghrelin showed a positive correlation with BMI in TB (r=0.695, p<0.05) and TB+T2DM (r= 0.199, p>0.05) groups, but negative correlation with BMI in the control (r=-0.693, p<0.05) group. Inflammatory cytokines were poorly correlated with BMI in this study. Only IFN-γ showed a significant negative correlation with BMI in the control group (r=-0.545, p<0.05).Conclusions
This study may suggest that possible abnormalities in ghrelin and leptin regulation (high levels of leptin and low levels of ghrelin) may be associated with low BMI and may account for the poor nutrition associated with TB and TB+T2DM. 相似文献5.
Eivind Aadland John Roger Andersen Sigmund Alfred Anderssen Olav Martin Kvalheim 《PloS one》2013,8(12)
Background
Physical activity (PA) and sedentary behavior (SED) may have independent effects on health and disease. This might be due to PA and SED having distinct effects on lipoprotein metabolism. The aim of this study was to determine associations between lipoprotein subclass particle concentrations (-P) and accelerometer-measured SED and moderate-to-vigorous PA (MVPA) in a sample of healthy adult subjects.Methods
Lipoprotein subclass particle concentrations were determined by proton nuclear magnetic resonance spectroscopy, whereas SED and MVPA were measured using Agtigraph GT1M and GT3X+ accelerometers. We obtained valid data in 73 subjects (30 men and 43 women, age 40.5 ± 10.6 years; body mass index 24.0 ± 2.8). Multiple regression analysis was used to determine associations (partial correlations) with lipoproteins.Results
Positive associations were detected between SED and small VLDL-P, large LDL-P and TG (partial r = 0.24 to 0.25, p < .047). Corresponding associations were non-significant for MVPA (partial r = -0.12 to 0.04, p > .355). On the contrary, MVPA was positively associated with large HDL-P, average HDL size, Apo A1 and HDL-cholesterol (partial r = 0.28 to 0.50, p < .027), whereas SED was not (partial r = -0.06 to 0.07, p > .607).Conclusion
There might be a specific effect of SED versus MVPA on lipoprotein metabolism. However, our results must be interpreted carefully due to possible effect-modification by gender and a low sample size. Thus, our findings should be viewed as preliminary. 相似文献6.
Mpiko Ntsekhe Kerryn Matthews Faisal F. Syed Armin Deffur Motasim Badri Patrick J. Commerford Bernard J. Gersh Katalin A. Wilkinson Robert J. Wilkinson Bongani M. Mayosi 《PloS one》2013,8(10)
Background
Effusive constrictive pericarditis (ECP) is visceral constriction in conjunction with compressive pericardial effusion. The prevalence of proven tuberculous ECP is unknown. Whilst ECP is distinguished from effusive disease on hemodynamic grounds, it is unknown whether effusive-constrictive physiology has a distinct cytokine profile. We conducted a prospective study of prevalence and cytokine profile of effusive-constrictive disease in patients with tuberculous pericardial effusion.Methods
From July 2006 through July 2009, the prevalence of ECP and serum and pericardial levels of inflammatory cytokines were determined in adults with tuberculous pericardial effusion. The diagnosis of ECP was made by combined pericardiocentesis and cardiac catheterization.Results
Of 91 patients evaluated, 68 had tuberculous pericarditis. The 36/68 patients (52.9%; 95% confidence interval [CI]: 41.2-65.4) with ECP were younger (29 versus 37 years, P=0.02), had a higher pre-pericardiocentesis right atrial pressure (17.0 versus 10.0 mmHg, P<0.0001), serum concentration of interleukin-10 (IL-10) (38.5 versus 0.2 pg/ml, P<0.001) and transforming growth factor-beta (121.5 versus 29.1 pg/ml, P=0.02), pericardial concentration of IL-10 (84.7 versus 20.4 pg/ml, P=0.006) and interferon-gamma (2,568.0 versus 906.6 pg/ml, P=0.03) than effusive non-constrictive cases. In multivariable regression analysis, right atrial pressure > 15 mmHg (odds ratio [OR] = 48, 95%CI: 8.7-265; P<0.0001) and IL-10 > 200 pg/ml (OR=10, 95%CI: 1.1, 93; P=0.04) were independently associated with ECP.Conclusion
Effusive-constrictive disease occurs in half of cases of tuberculous pericardial effusion, and is characterized by greater elevation in the pre-pericardiocentesis right atrial pressure and pericardial and serum IL-10 levels compared to patients with effusive non-constrictive tuberculous pericarditis. 相似文献7.
Megha Kaushik Chen Yu Wang Michael H. Barnett Raymond Garrick John Parratt Stuart L. Graham Prema Sriram Con Yiannikas Alexandr Klistorner 《PloS one》2013,8(10)
Aim
To examine the relationship between retinal ganglion cell loss and changes in the inner nuclear layer (INL) in optic neuritis (ON).Methods
36 multiple sclerosis (MS) patients with a history of ON and 36 age and sex-matched controls underwent Optical Coherence Tomography. The paramacular retinal nerve fiber layer (RNFL), combined ganglion cell and inner plexiform layers (GCL/IPL) and inner nuclear layer (INL) thickness were measured at 36 points around the fovea. To remove inter-subject variability, the difference in thickness of each layer between the ON and fellow eye of each patient was calculated. A topographic analysis was conducted.Results
The INL of the ON patients was thicker than the controls (42.9µm versus 39.6µm, p=0.002). ON patients also had a thinner RNFL (27.8µm versus 32.2µm, p<0.001) and GCL/IPL (69.3µm versus 98.1µm, p<0.001). Among the controls, there was no correlation between RNFL and GCL/IPL as well as RNFL and INL, but a positive correlation was seen between GCL/IPL and INL (r=0.65, p<0.001). In the ON group, there was a positive correlation between RNFL and GCL/IPL (r=0.80, p<0.001) but a negative correlation between RNFL and INL (r=-0.61, p<0.001) as well as GCL/IPL and INL (r=-0.44, p=0.007). The negative correlation between GCL/IPL and INL strengthened in the ON group when inter-subject variability was removed (r=-0.75, p<0.001). Microcysts within the INL were present in 5 ON patients, mainly in the superior and infero-nasal paramacular regions. While patients with microcysts lay at the far end of the correlation curve between GCL/IPL and INL (i.e. larger INL and smaller GCL/IPL compared to other patients), their exclusion did not affect the correlation (r= -0.76, p<0.001).Conclusions
INL enlargement in MS-related ON is associated with the severity of GCL loss. This is a continuous relationship and patients with INL microcysts may represent the extreme end of the scale. 相似文献8.
Yasuko Koma Akira Onishi Hirofumi Matsuoka Nao Oda Naoya Yokota Yusuke Matsumoto Midori Koyama Nobuhiko Okada Nariyasu Nakashima Daiki Masuya Harukazu Yoshimatsu Yujiro Suzuki 《PloS one》2013,8(11)
Background
Red cell distribution width (RDW), one of many routinely examined parameters, shows the heterogeneity in erythrocyte size. We investigated the association of RDW levels with clinical parameters and prognosis of lung cancer patients.Methods
Clinical and laboratory data from 332 patients with lung cancer in a single institution were retrospectively studied by univariate analysis. Kaplan-Meier survival analysis and Cox proportional hazard models were used to examine the effect of RDW on survival.Results
The RDW levels were divided into two groups: high RDW (>=15%), n=73 vs. low RDW, n=259 (<15%). Univariate analysis showed that there were significant associations of high RDW values with cancer stage, performance status, presence of other disease, white blood cell count, hemoglobin, mean corpuscular volume, platelet count, albumin level, C-reactive protein level, and cytokeratin 19 fragment level. Kruskal-Wallis tests revealed an association of RDW values with cancer stage in patients irrespective of comorbidity (patient with/without comorbidity: p<0.0001, patient without comorbidity: p<0.0001). Stages I-IV lung cancer patients with higher RDW values had poorer prognoses than those with lower RDW values (Wilcoxon test: p=0.002). In particular, the survival rates of stage I and II patients (n=141) were lower in the high RDW group (n=19) than in the low RDW group (n=122) (Wilcoxon test: p<0.001). Moreover, multivariate analysis showed higher RDW is a significant prognostic factor (p=0.040).Conclusion
RDW is associated with several factors that reflect inflammation and malnutrition in lung cancer patients. Moreover, high levels of RDW are associated with poor survival. RDW might be used as a new and convenient marker to determine a patient’s general condition and to predict the mortality risk of lung cancer patients. 相似文献9.
Hussein N. Yassine Olgica Trenchevska Huijuan He Chad R. Borges Dobrin Nedelkov Wendy Mack Naoko Kono Juraj Koska Peter D. Reaven Randall W. Nelson 《PloS one》2015,10(1)
Serum Amyloid A (SAA) is an acute phase protein complex consisting of several abundant isoforms. The N- terminus of SAA is critical to its function in amyloid formation. SAA is frequently truncated, either missing an arginine or an arginine-serine dipeptide, resulting in isoforms that may influence the capacity to form amyloid. However, the relative abundance of truncated SAA in diabetes and chronic kidney disease is not known.
Methods
Using mass spectrometric immunoassay, the abundance of SAA truncations relative to the native variants was examined in plasma of 91 participants with type 2 diabetes and chronic kidney disease and 69 participants without diabetes.Results
The ratio of SAA 1.1 (missing N-terminal arginine) to native SAA 1.1 was lower in diabetics compared to non-diabetics (p = 0.004), and in males compared to females (p<0.001). This ratio was negatively correlated with glycated hemoglobin (r = −0.32, p<0.001) and triglyceride concentrations (r = −0.37, p<0.001), and positively correlated with HDL cholesterol concentrations (r = 0.32, p<0.001).Conclusion
The relative abundance of the N-terminal arginine truncation of SAA1.1 is significantly decreased in diabetes and negatively correlates with measures of glycemic and lipid control. 相似文献10.
Objective
End-stage renal disease (ESRD) is a severe health concern over the world. Associations between apolipoprotein E (apoE) gene polymorphisms and the risk of ESRD remained inconclusive. This study aimed to investigate the association between apoE gene polymorphisms and ESRD susceptibility.Methods
Databases including PubMed, Embase, Web of Science and the Cochrane Library were searched to find relevant studies. Meta-analysis method was used synthesize the eligible studies.Results
Sixteen pertinent case-control studies which included 3510 cases and 13924 controls were analyzed. A significant association was found between ε2 allele and the ESRD risk (odds ratio (OR) = 1.30, 95% confidence interval (CI) 1.15–1.46, P < 0.0001; I 2 = 18%, P for heterogeneity = 0.24). The ε2ε3, ε2ε4, ε3ε3, ε3ε4, ε4ε4, ε3 and ε4 were not associated with the susceptibility of ESRD. In the subgroup analysis by ethnicity, there was a statistically significant association between ε2ε3 or ε2 allele and ESRD risk in East Asians (OR = 1.66, 95% CI 1.31–2.10, P < 0.0001; OR = 1.62, 95% CI 1.31–2.01, P < 0.0001, respectively), but not in Caucasians. E2 carriers had higher plasma apoE (mean difference = 16.24 mg/L, 95% CI 7.76-24.73, P = 0.0002) than the (ε3 + ε4) carriers in patients with ESRD. The publication bias was not significant.Conclusion
The ε2 allele of apoE gene might increase the risk of ESRD. E2 carriers expressed higher level of plasma apoE in patients with ESRD. More well-designed studies are needed to confirm these associations in the future. 相似文献11.
12.
Christian B. van der Pol Matthew D. F. McInnes William Petrcich Adam S. Tunis Ramez Hanna 《PloS one》2015,10(3)
Purpose
The purpose of this study is to determine whether study quality and completeness of reporting of systematic reviews (SR) and meta-analyses (MA) published in high impact factor (IF) radiology journals is associated with citation rates.Methods
All SR and MA published in English between Jan 2007–Dec 2011, in radiology journals with an IF >2.75, were identified on Ovid MEDLINE. The Assessing the Methodologic Quality of Systematic Reviews (AMSTAR) checklist for study quality, and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist for study completeness, was applied to each SR & MA. Each SR & MA was then searched in Google Scholar to yield a citation rate. Spearman correlation coefficients were used to assess the relationship between AMSTAR and PRISMA results with citation rate. Multivariate analyses were performed to account for the effect of journal IF and journal 5-year IF on correlation with citation rate. Values were reported as medians with interquartile range (IQR) provided.Results
129 studies from 11 journals were included (50 SR and 79 MA). Median AMSTAR result was 8.0/11 (IQR: 5–9) and median PRISMA result was 23.0/27 (IQR: 21–25). The median citation rate for SR & MA was 0.73 citations/month post-publication (IQR: 0.40–1.17). There was a positive correlation between both AMSTAR and PRISMA results and SR & MA citation rate; ρ=0.323 (P=0.0002) and ρ=0.327 (P=0.0002) respectively. Positive correlation persisted for AMSTAR and PRISMA results after journal IF was partialed out; ρ=0.243 (P=0.006) and ρ=0.256 (P=0.004), and after journal 5-year IF was partialed out; ρ=0.235 (P=0.008) and ρ=0.243 (P=0.006) respectively.Conclusion
There is a positive correlation between the quality and the completeness of a reported SR or MA with citation rate which persists when adjusted for journal IF and journal 5-year IF. 相似文献13.
Komal P. Kushwaha Jhuma Sankar M. Jeeva Sankar Arun Gupta J. P. Dadhich Y. P. Gupta Girish C. Bhatt Dilshad A. Ansari B. Sharma 《PloS one》2014,9(11)
Objective
Our primary objective was to evaluate the effect of peer counselling by mother support groups (MSG''s) in improving the infant and young child feeding (IYCF) practices in the community.Methods
We conducted this repeated-measure before and after study in the Lalitpur district of Uttar Pradesh, India between 2006 and 2011. We assessed the IYCF practices before and after creating MSG''s within the community. The feeding practices were reassessed at two time points–2 (T1) and 5 years (T2) after the intervention and compared with that of the pre-intervention phase (T0).Results
The total population covered by the project from the time of its initiation was 105000. A total of 425 (T0), 480 (T1) and 521 (T2) mother infant pairs were selected from this population. There was significant improvement in the following IYCF practices in the community (represented as %; adjOR (95% CI, p) such as initiation of breast feeding within 1 hour at both T1 (71% vs. 11%); 19.6 (13.6, 28.2, p = <0.0001)and T2 (62% vs. 11%); 13.3 (9.4, 18.9, p = <0.0001); use of prelacteal feeds at both T1 (67% vs. 15%); 12.6 (CI: 9.0, 17.6, p<0.0001) and T2 (67% vs. 5%); 44.4 (28.8, 68.4, p = <0.0001); rates of exclusive breast feeding for 6 months at both T1 (50% vs. 7%); 13.6 (7.6, 25.0, p = <0.0001) and T2 (60% vs. 7%); 20.5 (11.3, 37.2, p = <0.0001); initiation of complementary feeding at T1 (85% vs. 54%); 5.6 (3.6, 8.7, p = <0.0001) and T2 (96% vs. 54%); 22.9 (11.8, 44.1, p = <0.0001) and complementary feeding along with continued breast feeding at both T1 (36% vs. 4.5%); 6 (1.15, 31.4, p = 0.033) and T2 (42% vs. 4.5%); 8.06 (1.96, 49.1, p = 0.005) as compared to pre-intervention period (T0) after adjusting for important social and demographic variables.Conclusions
Peer counseling by MSG''s improved the IYCF practices in the district and could be sustained. 相似文献14.
Sushmita Das Ganesh Chandra Sahoo Pradeep Das Utpal Kant Singh Anil Kumar Jaiswal Prachi Singh Ranjeet Kumar Rishikesh Kumar 《PloS one》2016,11(2)
Objectives
To evaluate the contribution of breastfeeding to Rotavirus (RV)-induced antigenemia and/or RNAemia and disease severity in Indian children (<2 yrs age).Methods
Paired stool and serum samples were collected from (a) hospitalized infants with diarrhea (n = 145) and (b) healthy control infants without diarrhea (n = 28). Stool RV-antigen was screened in both groups by commercial rapid-test and enzyme immunoassay. The disease severity was scored and real-time-PCR was used for viral-load estimation. Serum was evaluated for RV-antigenemia by EIA and RV-RNAemia by RT-PCR. Data was stratified by age-group and breastfeeding status and compared.Results
Presence of RV-antigenemia and RV-RNAemia was positively related with presence of RV in stool. Disease severity and stool viral-load was significantly associated with RV-antigenemia[(r = 0.74; CI:0.66 to 0.84; P<0.0001,R2 = 0.59) and (r = -0.55; CI:-0.68 to -0.39; P<0.0001,R2 = 0.31) respectively], but not with RV-RNAemia. There was significant reduction in RV-antigenemiarate in the breast-fed group compared to non-breastfed infants, especially in 0–6 month age group (P<0.001). Non-breastfed infants were at risk for RV-antigenemia with severe disease manifestations in form of high Vesikari scores correlating with high fever, more vomiting episodes and dehydration.Conclusion
RV-antigenemia was common in nonbreastfed children with severe RV-diarrhea and correlated with stool RV-load and disease severity. 相似文献15.
Per Johansson Erik G. Almqvist Jan-Ove Johansson Niklas Mattsson Ulf Andreasson Oskar Hansson Anders Wallin Kaj Blennow Henrik Zetterberg Johan Svensson 《PloS one》2013,8(11)
Background
Little is known of vitamin D concentration in cerebrospinal fluid (CSF) in Alzheimer´s disease (AD) and its relation with CSF acetylcholinesterase (AChE) activity, a marker of cholinergic function.Methods
A cross-sectional study of 52 consecutive patients under primary evaluation of cognitive impairment and 17 healthy controls. The patients had AD dementia or mild cognitive impairment (MCI) diagnosed with AD dementia upon follow-up (n = 28), other dementias (n = 12), and stable MCI (SMCI, n = 12). We determined serum and CSF concentrations of calcium, parathyroid hormone (PTH), 25-hydroxyvitamin D (25OHD), and CSF activities of AChE and butyrylcholinesterase (BuChE).Findings
CSF 25OHD level was reduced in AD patients (P < 0.05), and CSF AChE activity was decreased both in patients with AD (P < 0.05) and other dementias (P < 0.01) compared to healthy controls. None of the measured variables differed between BuChE K-variant genotypes whereas the participants that were homozygous in terms of the apolipoprotein E (APOE) ε4 allele had decreased CSF AChE activity compared to subjects lacking the APOE ε4 allele (P = 0.01). In AD patients (n=28), CSF AChE activity correlated positively with CSF levels of total tau (T-tau) (r = 0.44, P < 0.05) and phosphorylated tau protein (P-tau) (r = 0.50, P < 0.01), but CSF activities of AChE or BuChE did not correlate with serum or CSF levels of 25OHD.Conclusions
In this pilot study, both CSF 25OHD level and CSF AChE activity were reduced in AD patients. However, the lack of correlations between 25OHD levels and CSF activities of AChE or BuChE might suggest different mechanisms of action, which could have implications for treatment trials. 相似文献16.
Barry S. Peters Melissa Perry Anthony S. Wierzbicki Lisa E. Wolber Glen M. Blake Nishma Patel Richard Hoile Alastair Duncan Ranjababu Kulasegaram Frances M. K. Williams 《PloS one》2013,8(10)
Objective
To determine comparative fracture risk in HIV patients compared with uninfected controls.Design
A randomised cross-sectional study assessing bone mineral density (BMD), fracture history and risk factors in the 2 groups.Setting
Hospital Outpatients.Subbbjects
222 HIV infected patients and an equal number of age-matched controls. Assessments: Fracture risk factors were assessed and biochemical, endocrine and bone markers measured. BMD was assessed at hip and spine. 10-year fracture probability (FRAX) and remaining lifetime fracture probability (RFLP) were calculated.Main Outcome Measures
BMD, and history of fractures.Results
Reported fractures occurred more frequently in HIV than controls, (45 vs. 16; 20.3 vs. 7%; OR=3.27; p=0.0001), and unsurprisingly in this age range, non-fragility fractures in men substantially contributed to this increase. Osteoporosis was more prevalent in patients with HIV (17.6% vs. 3.6%, p<0.0001). BMD was most reduced, and predicted fracture rates most increased, at the spine. Low BMD was associated with antiretroviral therapy (ART), low body mass index and PTH. 10-year FRAX risk was <5% for all groups. RLFP was greater in patients with HIV (OR=1.22; p=0.003) and increased with ART (2.4 vs. 1.50; OR= 1.50; p=0.03).Conclusions
The increased fracture rate in HIV patients in our relatively youthful population is partly driven by fractures, including non-fragility fractures, in men. Nonetheless, these findings may herald a rise in osteoporotic fractures in HIV patients. An appropriate screening and management response is required to assess these risks and identify associated lifestyle factors that are also associated with other conditions such as cardiovascular disease and diabetes. 相似文献17.
Xiuyu Chen Minjie Lu Gang Yin Tao Zhao Xiaoning Shao Ranxu Zhao Yue Tang Jing An Shiliang Jiang Shihua Zhao 《PloS one》2013,8(10)
Objectives
We sought to evaluate the feasibility and accuracy of free-breathing three-dimensional (3D) phase-sensitive inversion-recovery (PSIR) Turbo FLASH sequence for noninvasive assessment of left ventricular myocardial scar in swine models.Materials and Methods
Nine Chinese minipigs with experimentally induced acute myocardial infarction were studied. At 1 week and the study endpoint 4 weeks after myocardial infarction surgery, the 3D and 2D contrasted cardiac magnetic resonance (CMR) imaging were performed randomly by using a 1.5T clinical MR imaging system. Comparisons of myocardial scar volume (in cubic centimeters), scar transmurality (on a 5 points scale) and image quality (on a 4 points Likert scale) were performed by using the Pearson correlation and Bland-Altman analysis (for myocardial scar volume) or κ statistics (for transmurality) or Wilcoxon signed rank test (for image quality).Results
In 6 of the 9 pigs, all procedures were successfully completed. In these pigs, a total of 48 segments with myocardial scars were detected by both 3D and 2D sequences, and there was good agreement for classification of scar transmurality (κ=0.930). The scar volume determined by triphenyltetrazolium chloride (TTC) staining (3.52±1.40cm3) showed a good correlation with both 3D (3.54±1.36cm3, r=0.957, P=0.003) and 2D sequence (3.53±1.26cm3, r=0.942, P=0.005) at 4 weeks. And there were good correlation between scar volumes obtained from 3D and 2D techniques (r=0.859, P<0.001) at both time points. Both 3D and 2D images detected a small reduction of scar volume from week 1 to week 4 by a factor of 1.179 and 1.176, respectively. Although slightly more artifacts were observed on 2D PSIR images, the overall image quality was not significantly different between the two sequences (3.17±0.83 for 2D vs. 3.25±0.75 for 3D, P =0.655).Conclusions
The free-breathing 3D PSIR Turbo FLASH sequence enables accurate assessment of left ventricular myocardial scar. 相似文献18.
Purpose
To investigate the distribution of posterior corneal astigmatism in eyes with with-the-rule (WTR) and against-the-rule (ATR) anterior corneal astigmatism.Methods
We retrospectively examined six hundred eight eyes of 608 healthy subjects (275 men and 333 women; mean age ± standard deviation, 55.3 ± 20.2 years). The magnitude and axis orientation of anterior and posterior corneal astigmatism were determined with a rotating Scheimpflug system (Pentacam HR, Oculus) when we divided the subjects into WTR and ATR anterior corneal astigmatism groups.Results
The mean magnitudes of anterior and posterior corneal astigmatism were 1.14 ± 0.76 diopters (D), and 0.37 ± 0.19 D, respectively. We found a significant correlation between the magnitudes of anterior and posterior corneal astigmatism (Pearson correlation coefficient r = 0.4739, P<0.001). In the WTR anterior astigmatism group, we found ATR astigmatism of the posterior corneal surface in 402 eyes (96.6%). In the ATR anterior astigmatism group, we found ATR posterior corneal astigmatism in 82 eyes (73.9%). Especially in eyes with ATR anterior corneal astigmatism of 1 D or more and 1.5 D or more, ATR posterior corneal astigmatism was found in 28 eyes (59.6%) and 9 eyes (42.9%), respectively.Conclusions
WTR anterior astigmatism and ATR posterior astigmatism were found in approximately 68% and 91% of eyes, respectively. The magnitude and the axis orientation of posterior corneal astigmatism were not constant, especially in eyes having high ATR anterior corneal astigmatism, as is often the case in patients who have undergone toric IOL implantation. 相似文献19.
Background
Guidelines recommend that adults with congenital heart disease (CHD) undergo noncardiac surgery in regionalized centers of expertise, but no studies have assessed whether this occurs in the United States. We hypothesized that adults with CHD are less likely than children to receive care at specialized CHD centers.Methods
Using a comprehensive state ambulatory surgical registry (California Ambulatory Surgery Database, 2005–2011), we calculated the proportion of adult and pediatric patients with CHD who had surgery at a CHD center, distance to the nearest CHD center, and distance to the facility where surgery was performed.Results
Patients with CHD accounted for a larger proportion of the pediatric population (n = 11,254, 1.0%) than the adult population (n = 10,547, 0.07%). Only 2,741 (26.0%) adults with CHD had surgery in a CHD center compared to 6,403 (56.9%) children (p<0.0001). Adult CHD patients who had surgery at a non-specialty center (11.9±15.4 miles away) lived farther from the nearest CHD center (37.9±43.0 miles) than adult CHD patients who had surgery at a CHD center (23.2±28.4 miles; p<0.0001). Pediatric CHD patients who had surgery at a non-specialty center (18.0±20.7 miles away) lived farther from the nearest CHD center (35.7±45.2 miles) than pediatric CHD patients who had surgery at a CHD center (22.4±26.0 miles; p<0.0001).Conclusions
Unlike children with CHD, most adults with CHD (74%) do not have outpatient surgery at a CHD center. For both adults and children with CHD, greater distance from a CHD center is associated with having surgery at a non-specialty center. These results have significant public health implications in that they suggest a failing to achieve adequate regional access to specialized ACHD care. Further studies will be required to evaluate potential strategies to more reliably direct this vulnerable population to centers of expertise. 相似文献20.
Michael Haimerl Niklas Verloh Florian Zeman Claudia Fellner René Müller-Wille Andreas G. Schreyer Christian Stroszczynski Philipp Wiggermann 《PloS one》2013,8(12)