bluuebunny/crossref_metadata_2025_split huggingface dataset:
Poor recognition of the UK minimum driving vision standard by motorists attending optometric practice
Authors: Pointer Jonathan S. 
Published: May 2007

AbstractPurpose:  To evaluate the current level of recollection of the vehicle number plate viewing distance in a group of motorists. Knowledge of this distance is required to self‐check compliance with the UK legal minimum driving vision standard.Methods:  A cohort of 480 motorists aged ≥17 years attending optometric practice for a routine sight test agreed to participate in a short verbal survey. They were asked whether they could state the current UK statutory vehicle number plate viewing distance as specified in the Highway Code. Also recorded were each motorist's high contrast logMAR visual acuity, whether or not an optical prescription was habitually worn when driving, and brief demographic details (age, gender).Results:  No statistically significant gender‐based difference was present in age distribution, mean logMAR binocular acuity, or age and number (proportion) of motorists who habitually wore a refractive correction when driving. The level of mean binocular acuity was uniformly good (<0.0 logMAR, or better than 6/6 Snellen). However, the recollection by respondents of the statutory viewing distance was poor: only 5% were able to state correctly the current distance (20 m), and 22% recalled the previous (20.5 m/67 ft) or the original (22.9 m/75 ft) statutory distance. Of the remainder, 28% underestimated and 45% overestimated the distance. A statistically significant gender‐based difference (p = 0.01) between the recollections of non‐prescription wearers became marked (p = 0.001) for habitual wearers, in which latter case the median value and range of estimates by female motorists was greater than their male counterparts.Conclusions:  The level of recognition by these motorists of the viewing distance necessary to satisfy the legal minimum vision standard required for driving on UK roads was low and comparable to the levels recorded in two similar surveys undertaken by other authors 10 and 20 years ago. An inexpensive and easily implemented publicity innovation is suggested which could help improve driver appreciation of the statutory distance and promote compliance with the legal vision standard.
Investigation of the effect of simulated lens yellowing, transparency loss and refractive error on in vivo resonance Raman spectroscopy
Authors: Hogg R. E. , Zlatkova M. B. , Chakravarthy U. , Anderson R. S. 
Published: May 2007

AbstractPurpose:  To separately investigate the impact of simulated age‐related lens yellowing, transparency loss and refractive error on measurements of macular pigment (MP) using resonance Raman spectroscopy.Methods:  Two healthy young subjects with clear media underwent Raman spectroscopy under the following conditions: age‐related lens yellowing was simulated using seven broad‐band yellow filters with transmittance at 488 nm ranging from 0.54 to 0.90; cataract was simulated using five white filters of increasing opacity (scatter filters), the transmittance of which ranged from 0.42 to 0.86, each of which reduced peak contrast sensitivity by approximately 0.1 log units over the previous filter. Refractive error up to +6.25 D was achieved using soft contact lenses.Results:  The Raman signal declined steadily to an average value of 43% of the starting value with the densest yellow filter in place. The white scatter filters produced a progressive linear reduction in signal resulting in almost complete signal loss with the densest filter. Refractive error resulted in an initial slight improvement in Raman count up to a value of +2.00 D followed by a decline thereafter.Conclusions:  These results imply that lens yellowing and increasing scatter has an influence on the Raman signal and suggest that studies using this technology to estimate MP levels in older populations should carefully account for the status of the lens.
Manganese superoxide dismutase activity and incidence of hepatocellular carcinoma in patients with Child–Pugh class A liver cirrhosis: a 7‐year follow‐up study
Authors: Clemente Caterina , Elba Silvana , Buongiorno Gianpiero , Guerra Vito , D'Attoma Benedetta , Orlando Antonella , Russo Francesco 
Published: May 2007

AbstractAims: To evaluate possible modifications in the manganese superoxide dismutase (MnSOD) activity during neoplastic transformation of a cirrhotic liver and to find out whether its assessment may have predictive value to identify cirrhotic patients at a higher risk of hepatocellular carcinoma (HCC).Methods: Seventy‐one consecutive subjects with Child–Pugh class A liver cirrhosis were recruited. At the time of enrolment, HCC was diagnosed in 20 cirrhotic patients. The 51 cirrhotic patients without HCC were followed up for the occurrence of tumour by 6‐monthly screening for 7 years. During follow‐up, 16 patients developed HCC. Seventy healthy subjects formed the control group. MnSOD activity was assayed spectrophotometrically.Results: Serum MnSOD activity was significantly lower in 70 healthy subjects compared with 51 cirrhotic patients and 20 cirrhotic patients with HCC. Cirrhotic patients who developed HCC during follow‐up showed significantly higher values of MnSOD activity than HCC‐free patients. The best cut‐off of MnSOD activity was 0.40 U/ml. At this cut‐off, χ2 analysis revealed that MnSOD activity was significantly different between the HCC‐free cirrhotic patients and cirrhotic patients who developed HCC.Conclusion: The present findings suggest that during neoplastic transformation of cirrhotic liver, an increase in MnSOD activity may occur already during the precancerous phase, making this enzyme a probable malignancy‐associated parameter.
Quantitative ultrasonic tissue characterization as a new tool for continuous monitoring of chronic liver remodelling in mice
Authors: Guimond Alain , Teletin Marius , Garo Erwan , D'Sa Alwyn , Selloum Mohamed , Champy Marie‐France , Vonesch Jean‐Luc , Monassier Laurent 
Published: May 2007

AbstractBackground/Aim: Recognition of the limitations of liver biopsies has led to the need for non‐invasive tests to assess liver fibrosis from intensity and kinetic point of views. The aim of the present study was to evaluate non‐invasive ultrasonic tissue characterization for the continuous monitoring of this process in mice.Methods: Twelve‐week‐old male and female C57Bl6/J mice were submitted to repetitive carbon‐tetrachloride (CCl4) intraperitoneal injections during 8 weeks or analysed 28 days after common bile duct ligation (BDL). The extent and kinetic of the disease progression were followed by the measurement of ultrasound backscatter intensity. This was compared with histological and blood parameter analysis.Results: CCl4 induced a progressive increase in in vivo liver tissue backscatter intensity in both males and females. This increase was mainly correlated with interstitial fibrosis and, to a lower extent, with nuclear surface of the hepatocytes. A similar result was found after BDL.Conclusions: These data demonstrate for the first time in a systematic study that ultrasound tissue characterization can be used as a reliable tool to follow liver remodelling in mice continuously.
P21/WAF1 is an independent survival prognostic factor for patients with hepatocellular carcinoma after resection
Authors: Kao Jung‐Ta , Chuah Seng‐Kee , Huang Chao‐Cheng , Chen Chao‐Long , Wang Chih‐Chi , Hung Chao‐Hung , Chen Chien‐Hung , Wang Jing‐Houng , Lu Sheng‐Nan , Lee Chuan‐Mo , Changchien Chi‐Sin , Hu Tsung‐Hui 
Published: May 2007

AbstractBackground/Aims: The cyclin kinase inhibitor p21/WAF1 is regulated by p53‐dependent or independent pathways and inhibits the action of proliferating cell nuclear antigen (PCNA). The prognostic role of p21/WAF1 in hepatocellular carcinoma (HCC) is ambiguous. To further clarify this, we examined the expression of three genes in HCC.Methods: A total of 122 resected HCC specimens were collected from 1987 to 1998. Expression of p21/WAF1, p53, and PCNA in HCC was analysed by immunohistochemistry.Results: Immunoreactivity was detectable for p21/WAF1 in 37%, and for p53 in 41.8% of HCCs. Positive expression of both genes does not relate to each other, but both are associated with a high PCNA labelling index (LI) (P<0.05) in tumour. p53 (+) is also associated with high serum α‐foetoprotein (αFP) (P<0.001), tumour dedifferentiation (P=0.001) and advanced pathologic stages (P=0.017). However, p21/WAF1 (+) did not show clinicopathologic significance. Survival analysis indicated that poor prognostic factors were p21/WAF1 (−) (P=0.024), p53 (+) (P=0.008), high PCNA (P<0.001), tumour without capsule (P=0.001), poor tumour differentiation (P=0.004), advanced pathologic stage (P<0.001), and high serum αFP(P<0.001). Independent factors were p21/WAF1 expression, pathologic stage, and PCNA.Conclusion: In HCC, increased proliferation index PCNA is significantly associated with positive p53 and p21/WAF1. But p21/WAF1 expression did not relate to p53 expression. P21/WAF1 (+) is a good event and serves as an independent survival prognostic factor for HCC, which is a novel finding apart from previous reports.
The intention‐to‐treat principle in clinical trials and meta‐analyses of leukoreduced blood transfusions in surgical patients
Authors: Blumberg Neil , Zhao Hongwei , Wang Hongkun , Messing Susan , Heal Joanna M. , Lyman Gary H. 
Published: May 2007

BACKGROUND: The scientific method requires that only experiments actually and correctly performed be used to draw conclusions. The intention‐to‐treat principle requires that all patients, even those not or improperly treated, be included. In clinical trials and meta‐analyses investigating leukoreduced blood transfusions to reduce postoperative infections, the intention‐to‐treat principle and the scientific method have been variably applied.STUDY DESIGN AND METHODS: Clinical trials and meta‐analyses were retrieved from the literature, and their scientific and statistical methods were assessed. A meta‐analysis emphasizing the scientific method was created, restricted to patients who actually received transfusions, given that patients who did not receive transfusions cannot benefit from leukoreduction.RESULTS: Nine clinical trials and 11 meta‐analyses were identified. In 2 of the trials and all but 1 of the meta‐analyses, conclusions were based on data that included many (>10%) patients who had been randomly assigned but not received a transfusion or data not derived from investigative results. Limiting the meta‐analysis to patients who actually received transfusions (n = 3093), demonstrated that leukoreduced transfusions significantly reduced the odds of postoperative infection (summary odds ratio, 0.522; 95% confidence interval, 0.332‐0.821; p = 0.005).CONCLUSION: When data restricted to patients receiving transfusions are analyzed, and no data absent from the actual investigations are introduced, leukoreduced transfusions substantially and significantly reduce the odds of postoperative infection by approximately 50 percent. These results demonstrate the importance of including only scientifically valid data in clinical trials and meta‐analyses. The intention‐to‐treat principle should never lead to inclusion of data not actually derived from experimental results.
Rapid detection of HPA‐1 alloantibodies by platelet antigens immobilized onto microbeads
Authors: Bakchoul Tamam , Meyer Oliver , Agaylan Ashraf , Bombard Stephane , Bein Gregor , Sachs Ulrich J.H. , Salama Abdulgabar , Santoso Sentot 
Published: May 2007

BACKGROUND: Neonatal alloimmune thrombocytopenia (NAIT) is one of the most common bleeding disorders in neonates. It occurs when alloantibodies from an immunized mother react with paternally inherited alloantigens, mostly human platelet antigen 1a (HPA‐1a), on the fetal platelets (PLTs). Currently, monoclonal antibody–immobilized PLT antigen (MAIPA) assay represents the standard technique for the serologic diagnosis of NAIT. MAIPA is time‐consuming, however, and limited by the availability of monoclonal antibodies (MoAbs). Here, a gel antigen‐specific assay (GASA) was developed, which allows rapid detection of HPA‐1 alloantibodies without the use of MoAbs.STUDY DESIGN AND METHODS: Glycoprotein (GP) IIb/IIIa was purified by affinity chromatography from outdated PLT concentrates derived from HPA‐1aa or HPA‐1bb donors. Purified GPs were biotinylated, immobilized onto streptavidin beads, and used for the analysis of HPA‐1a alloantibodies by a microtyping system. HPA‐1a serum samples derived from mothers with NAIT (n = 36) and from posttransfusion purpura patients (n = 2) as well as HPA‐1b (n = 4), HPA‐5b (n = 2), HPA‐3a (n = 4), and HLA Class I (n = 2) alloantiserum samples from multitransfused patients were investigated in GASA and MAIPA assays.RESULTS: GASA was able to detect all HPA‐1a and ‐1b alloantibodies recognized by MAIPA. Cross‐reactivity with other PLT‐reactive alloantibodies was not observed. Interestingly, 3 of 36 serum samples, which showed only moderate reactivity in MAIPA, reacted strongly in GASA.CONCLUSION: GASA has proved to be a rapid method for the detection of HPA‐1a alloantibodies and maybe useful for PLT antibody screening, especially in initial assessment of suspected NAIT cases.
A Rate‐Independent Method of Assessing QT‐RR Slope Following Conversion of Atrial Fibrillation
Authors: DARBAR DAWOOD , HARDIN BRADLEY , HARRIS PAUL , RODEN DAN M. 
Published: May 2007

Introduction: Following conversion of atrial fibrillation (AF), QT interval transiently and variably prolongs and can trigger Torsades de Pointes (TdP). However, quantitative analysis of risk in this setting is difficult because cycle length variability during AF makes rate‐corrected QT impossible to calculate. In this study, a newly developed method to study heart rate dependence of the QT interval during AF was applied to assess the QT–RR relationships prior to and following cardioversion in patients with AF. Methods and Results: Cardiac rhythm was digitized for ≥30 minutes prior to and following elective cardioversion to sinus rhythm (SR) in 12 patients. Each QT interval was placed in a “bin” (50 ms), according to the preceding RR interval. All QT intervals within a bin were averaged and RR bin‐specific QT values were derived. The slope of the QT–RR relationship was much flatter in AF (0.058 ± 0.02) compared with that predicted by conventionally used QT rate corrections (0.130 [Bazett], 0.096 [Fridericia]) and much steeper after cardioversion (0.238 ± 0.14, P < 0.01 compared with AF). The method also allowed us to establish that QT at any given RR interval prolonged when SR was restored (e.g., at RR interval 800 ms: QT = 0.38 ± 0.03 second [AF] vs 0.46 ± 0.05 second [SR], P < 0.01). The longest QT values were in patients receiving sotalol or quinidine. Conclusions: The results of this study demonstrate that QT interval can be reliably measured in AF using a method that is independent of heart rate. We also showed that cardioversion of AF acutely increases the QT interval and the steepness of the QT–RR slope.
Cryoablation of Accessory Pathways in the Coronary Sinus in Young Patients: A Multicenter Study from the Pediatric and Congenital Electrophysiology Society's Working Group on Cryoablation
Authors: COLLINS KATHRYN K. , RHEE EDWARD K. , KIRSH JOEL A. , CANNON BRYAN C. , FISH FRANK A. , DUBIN ANNE M. , VAN HARE GEORGE F. 
Published: May 2007

Introduction: This is a multicenter retrospective study evaluating the immediate‐ and mid‐term outcomes of cryoablation of accessory pathways in the coronary sinus in children or in patients with congenital heart disease. Methods and Results: Twenty‐one patients (median age 13.0 years, range 2–40) from six institutions were included. The accessory pathways were concealed in 11 and manifest in 10. Of 12 patients who had coronary sinus angiography, two had large coronary sinus diverticula, one had a dilated coronary sinus due to a left superior vena cava to coronary sinus, and one had a “pouch” at the mouth of the coronary sinus. Six patients underwent ablation procedures with cryoablation alone, while in the remaining 15 patients, both cryoablation and radiofrequency ablation were utilized. The ablation procedure included left‐sided endocardial mapping via a retrograde or transeptal approach in 13 (62%). Procedural success was achieved with cryoablation in the coronary sinus in 15/21 (71%). Four patients (19%) had successful radiofrequency ablation at the right or left posterior septum. Two patients (10%) had unsuccessful procedures. Of the 15 patients with initially successful cryoablation procedures, six (40%) had arrhythmia recurrences at a median of 17 days (range 1–120). Recurrences could not be explained by differences in patient or procedural variables. Conclusion: Cryoablation in the coronary venous system in young patients is feasible but associated with a high arrhythmia recurrence rate. Cryoablation techniques and/or equipment need to be improved in order to safely create more permanent lesions in this arrhythmia substrate.
Histological and immunohistochemical analysis of initial and early osseous integration at chemically modified and conventional SLA® titanium implants: preliminary results of a pilot study in dogs
Authors: Schwarz Frank , Herten Monika , Sager Martin , Wieland Marco , Dard Michel , Becker Jürgen 
Published: May 2007

AbstractObjectives: The aim of the present pilot study was to investigate initial and early tissue reactions to modified (mod) and conventional sand‐blasted, large grit and acid‐etched (SLA) titanium implants.Material and methods: Implantation of modSLA and SLA implants was performed bilaterally in both the mandible and maxilla of dogs. The animals were sacrificed after a healing period of 1, 4, 7 and 14 days, respectively. Peri‐implant tissue reactions were assessed in non‐decalcified tissue sections using conventional histology (Toluidine blue‐TB and Masson Goldner Trichrome stain‐MG) and immunohistochemistry using monoclonal antibodies to transglutaminase II (TG) (angiogenesis) and osteocalcin (OC). Bone density (BD) and bone to implant contact (BIC) were assessed histomorphometrically.Results: Day 1 revealed an early TG antigen reactivity in the provisional fibrin matrix adjacent to both implant surfaces. Day 4 was characterized by the formation of a collagen‐rich connective tissue (MG), which revealed the first signs of OC synthesis adjacent to modSLA surfaces. Immunohistochemical staining for TG revealed a direct correlation between angiogenesis and new bone formation, which was clearly identifiable after 7 days by means of increasing BD, BIC and OC values. After 14 days, modSLA surfaces seemed to be surrounded by a firmly attached mature, parallel‐fibered woven bone.Conclusions: Within the limits of the present study, it might be concluded that the combination of immunohistochemical and conventional histological stainings in non‐decalcified tissue sections is a valuable technique to evaluate the initial and early stages of wound healing around endosseous titanium implants.
Effect of high environmental temperatures on ascorbic acid, sulfhydryl residue and oxidized lipid concentrations in plasma of dairy cows
Authors: TANAKA Masahito , KAMIYA Yuko , KAMIYA Mitsuru , NAKAI Yutaka 
Published: May 2007

ABSTRACTInformation on oxidative stress under hot conditions from the levels of cells to organs and the whole body has accumulated in the last decades. Although a hot climate decreased dairy performance, changes of oxidative stress markers under hot conditions have remained obscure. Therefore, the effect of high environmental temperature on ascorbic acid, sulfhydryl (SH) residue and oxidized lipids concentrations in plasma from a total of 128 dairy cows was investigated. The monthly average maximum day temperature varied from 9.2°C in January to 32°C in August of 2004 in this institute. High ambient temperatures increased the rectal temperature of dairy cows up to 39.3°C in August. One of the reducing equivalents in plasma, SH residue concentration, decreased in July compared with December (P < 0.05). Another antiradical molecule, ascorbic acid concentration in plasma, also decreased in July (P < 0.01). The oxidative stress index, thiobarbituric acid reactive substance (TBARS), which was produced from the oxidation of polyunsaturated fatty acids under oxidative conditions, increased in summer (P < 0.05). A significant positive relationship of SH residue and ascorbic acid concentrations in the hot season was observed (P < 0.01). A negative correlation between rectal temperatures and ascorbic acid concentrations in the hot season was obtained (P < 0.01). However, TBARS concentration varied independently of the SH residue and ascorbic acid concentration. These results suggest that the response of oxidative stress markers of SH residue, ascorbic acid and TBARS concentration to oxidative stress under hot conditions were not shown to be the same, and that oxidative stress in dairy cows in the hot season increased.
Temporal and spatial spread of Lettuce mosaic virus in lettuce crops in central Spain: factors involved in Lettuce mosaic virus epidemics
Authors: Moreno A. , Nebreda M. , Diaz B.M. , García M. , Salas F. , Fereres A. 
Published: May 2007

Abstract Lettuce mosaic virus (LMV) is transmitted by aphid vectors in a nonpersistent manner as well as by seeds. The virus causes severe disease outbreaks in commercial lettuce crops in several regions of Spain. The temporal and spatial patterns of spread of LMV were studied in autumn 2002 in the central region of Spain. Symptomatic lettuce (var. Cazorla) plant samples were collected weekly, first at the seedling stage from the greenhouse nursery and later outdoors after transplantation. The exact position of symptomatic plants sampled in the field was recorded and then material was tested by enzyme‐linked immunosorbent assay to assess virus infection. Cumulative spatial data for infected plants at different growth stages were analysed using spatial analysis by distance indices. For temporal analysis, the monomolecular, Gompertz, logistic and exponential models were evaluated for goodness of fit to the entire set of disease progress data obtained. The results indicated that the disease progress curve of LMV epidemics in the selected area is best described by a Gompertz model and that the epidemic follows a polycyclic disease progression. Our data suggest that secondary cycle of spread occurs when noncolonising aphid species land on the primary infected plants (probably coming from infected seed) and move to adjacent plants before leaving the crop. The role of weeds growing close to lettuce fields as potential inoculum sources of virus and the aphid species most likely involved in the transmission of LMV were also identified.
Riqueza y Distribución Ecológica de Especies de Pteridofitas en la Zona del Río Yavarí‐Mirín, Amazonía Peruana
Authors: Cárdenas Glenda G. , Halme y Hanna Tuomisto Kati J. 
Published: May 2007

ABSTRACTWe studied the ecological distribution of pteridophytes (ferns and fern allies) along eight 8‐km transects covering 12.7 ha in Peruvian Amazonia. Subunits of 200 m2 of the transects have previously been classified into four different forest types, and here we document and quantify the floristic differences among these forest types. Pteridophytes have been suggested as an indicator group to classify rain forest habitats, but this requires that the ecological preferences of the species are well documented and consistent across geographic regions. Here we analyzed in detail the distribution and diversity patterns of 130 species across the four rain forest types. Relative species abundance and species diversity were similar among some of the forest types and differed among others, but the species composition differed markedly. Our results largely confirmed the earlier interpretation of the edaphic preferences of the pteridophyte species in western Amazonia. This supports the proposition that deterministic processes have an important role in influencing the floristic composition of Amazonian forests.