bluuebunny/crossref_metadata_2025_split huggingface dataset:
Divergent character clines across a recent secondary contact zone in a Hispaniolan lizard
Authors: Gifford M. E. 
Published: October 2007

AbstractStudies of genetic contact zones provide valuable information regarding the processes of population divergence, adaptation and speciation. In this paper, I examine transitions in morphology, mitochondrial DNA (mtDNA) and nuclear DNA (nDNA) haplotypes across a recent secondary contact zone in a Hispaniolan lizardAmeiva chrysolaema. Maximum likelihood cline fitting analyses suggest non‐coincidence of cline centers and that the mtDNA cline is significantly displaced to the west of the remaining clines. nDNA and morphological clines are coincident and tend to be associated with the prevailing environmental gradient. The lack of cytonuclear disequilibrium near the center of the contact zone and the non‐coincidence of character clines suggest that this zone does not conform to a tension zone model of hybridization; thus, gene flow across the zone does not seem to be impeded. The extremely narrow width of the dorsal scale size cline and the close association of this cline with the steepness of the environmental (precipitation) gradient suggest that this character may be under environmental selection. Taken together, this contact zone appears to be structured by a combination of mtDNA introgression, possibly associated with eastward movement of the zone, and environmental selection on some characters.
Tachykinin regulation of cholinergic transmission in the limbic/prefrontal territory of the rat dorsal striatum: implication of new neurokinine 1‐sensitive receptor binding site and interaction with enkephalin/mu opioid receptor transmission
Authors: Pérez Sylvie , Tierney Adrienne , Deniau Jean‐Michel , Kemel Marie‐Louise 
Published: October 2007

AbstractThe tachykinin neurokinin 1 receptors (NK1Rs) regulation of acetylcholine release and its interaction with the enkephalin/mu opioid receptors (MORs) transmission was investigated in the limbic/prefrontal (PF) territory of the dorsal striatum. Using double immunohistochemistry, we first showed that in this territory, cholinergic interneurons contain tachykinin NK1Rs and co‐express MORs in the last part of the light period (afternoon). In slices of the striatal limbic/PF territory, following suppression of the dopaminergic inhibitory control of acetylcholine release, application of the tachykinin NK1R antagonist, SSR240600, markedly reduced the NMDA‐induced acetylcholine release in the morning but not in the afternoon when the enkephalin/MOR regulation is operational. In the afternoon, the NK1R antagonist response required the suppression of the enkephalin/MOR inhibitory control of acetylcholine release by βfunaltrexamine. The pharmacological profile of the tachykinin NK1R regulation tested by application of the receptor agonists [[Pro9]substance P, neurokinin A, neuropeptide K, and substance P(6–11)] and antagonists (SSR240600, GR205171, GR82334, and RP67580) indicated that the subtype of tachykinin NK1R implicated are the new NK1‐sensitive receptor binding site. Therefore, in the limbic/PF territory of the dorsal striatum, endogenous tachykinin facilitates acetylcholine release via a tachykinin NK1R subtype. In the afternoon, the tachykinin/NK1R and the enkephalin/MOR transmissions interact to control cholinergic transmission.
Rapid estrogen regulation of DHEA metabolism in the male and female songbird brain
Authors: Pradhan Devaleena S. , Yu Yan , Soma Kiran K. 
Published: October 2007

AbstractIn the songbird brain, dehydroepiandrosterone (DHEA) is metabolized to the active and aromatizable androgen androstenedione (AE) by 3β‐hydroxysteroid dehydrogenase/Δ5‐Δ4 isomerase (3β‐HSD). Thus, brain 3β‐HSD plays a key role in regulating the steroidal milieu of the nervous system. Previous studies have shown that stress rapidly regulates brain 3β‐HSD activity in a sex‐specific manner. To elucidate endocrine regulation of brain 3β‐HSD, we asked whether 17β‐estradiol (E2) regulates DHEA metabolism in adult zebra finch (Taeniopygia guttata) and whether there are sex‐specific effects. Brain tissue was homogenized and centrifuged to obtain supernatant lacking whole cells and cell nuclei. Supernatant was incubated with [3H]DHEA and radioinert E2in vitro. Within only 10 min, E2 significantly reduced 3β‐HSD activity in both male and female brain. Interestingly, the rapid effects of E2 were more pronounced in females than males. These are the first data to show a rapid effect of estrogens on the songbird brain and suggest that rapid estrogen effects differ between male and female brains.
Hydroxytyrosol protects retinal pigment epithelial cells from acrolein‐induced oxidative stress and mitochondrial dysfunction
Authors: Liu Zhongbo , Sun Lijuan , Zhu Lu , Jia Xu , Li Xuesen , Jia Haiqun , Wang Ying , Weber Peter , Long Jiangang , Liu Jiankang 
Published: October 2007

AbstractHydroxytyrosol (HTS) is a natural polyphenol abundant in olive oil. Increasing evidence indicates HTS has beneficial effect on human health for preventing various diseases. In the present study, we investigated the protective effects of HTS on acrolein‐induced toxicity in human retinal pigment epithelial cell line, ARPE‐19, a cellular model of smoking‐ and age‐related macular degeneration. Acrolein, a major component of the gas phase cigarette smoke and also a product of lipid peroxidation in vivo, at 75 μmol/L for 24 h caused significant loss of cell viability, oxidative damage (increase in oxidant generation and oxidative damage to proteins and DNA, decrease in antioxidants and antioxidant enzymes, and also inactivation of the Keap1/Nrf2 pathway), and mitochondrial dysfunction (decrease in membrane potential, activities of mitochondrial complexes, viable mitochondria, oxygen consumption, and factors for mitochondrial biogenesis, and increase in calcium). Pre‐treatment with HTS dose dependently and also time dependently protected the ARPE‐19 cells from acrolein‐induced oxidative damage and mitochondrial dysfunction. A short‐term pre‐treatment with HTS (48 h) required > 75 μmol/L for showing protection while a long‐term pre‐treatment (7 days) showed protective effect from 5 μmol/L on. The protective effect of HTS in this model was as potent as that of established mitochondria‐targeting antioxidant nutrients. These results suggest that HTS is also a mitochondrial‐targeting antioxidant nutrient and that dietary administration of HTS may be an effective measure in reducing and or preventing cigarette smoke‐induced or age‐related retinal pigment epithelial degeneration, such as age‐associated macular degeneration.
Thirteen nuclear microsatellite loci for butternut (Juglans cinerea L.)
Authors: HOBAN SEAN , ANDERSON ROBERT , MCCLEARY TIM , SCHLARBAUM SCOTT , ROMERO‐SEVERSON JEANNE 
Published: October 2007

AbstractButternut (Juglans cinerea L.) is an eastern North American forest tree severely threatened by an exotic fungal pathogen, Sirococcus clavigignenti‐juglandacearum. We report here 13 nuclear microsatellites for genetic evaluation of the remaining natural populations. Summary statistics are reported for individuals from a population of butternuts in central Kentucky (N = 63). All markers were polymorphic, with an average of 13.7 alleles per locus observed. Four loci exhibited significantly fewer heterozygotes than expected under Hardy–Weinberg equilibrium (P < 0.05).
Subjective refraction: the mechanism underlying the routine
Authors: Harris W. F. 
Published: October 2007

AbstractThe routine of subjective refraction is usually understood, explained and taught in terms of the relative positions of line or point foci and the retina. This paper argues that such an approach makes unnecessary and sometimes invalid assumptions about what is actually happening inside the eye. The only assumption necessary in fact is that the subject is able to guide the refractionist to (or close to) the optimum power for refractive compensation. The routine works even in eyes in which the interval of Sturm does not behave as supposed; it would work, in fact, regardless of the structure of the eye. The idealized subjective refraction routine consists of two steps: the first finds the best sphere (the stigmatic component) and the second finds the remaining Jackson cross‐cylinder (the antistigmatic component). The model makes use of the concept of symmetric dioptric power space. The second part of the refraction routine can be performed with Jackson cross‐cylinders alone. However, it is usually taught and practiced using spheres, cylinders and Jackson cross‐cylinders in a procedure that is not easy to understand and learn. Recognizing that this part of the routine is equivalent to one involving Jackson cross‐cylinders only allows one to teach and understand the procedure more naturally and easily.
Image quality characteristics of a novel colour scanning digital ophthalmoscope (SDO) compared with fundus photography
Authors: Strauss Rupert W. , Krieglstein Tina R. , Priglinger Siegfried G. , Reis Werner , Ulbig Michael W. , Kampik Anselm , Neubauer Aljoscha S. 
Published: October 2007

AbstractPurpose:  To establish a set of quality parameters for grading image quality and apply those to evaluate the fundus image quality obtained by a new scanning digital ophthalmoscope (SDO) compared with standard slide photography.Methods:  On visual analogue scales a total of eight image characteristics were defined: overall quality, contrast, colour brilliance, focus (sharpness), resolution and details, noise, artefacts and validity of clinical assessment. Grading was repeated after 4 months to assess repeatability. Fundus images of 23 patients imaged digitally by SDO and by Zeiss 450FF fundus camera using Kodak film were graded side‐by‐side by three graders. Lens opacity was quantified with the Interzeag Lens Opacity Meter 701.Results:  For all of the eight scales of image quality, good repeatability within the graders (mean Kendall’s W 0.69) was obtained after 4 months. Inter‐grader agreement ranged between 0.31 and 0.66. Despite the SDO’s limited nominal image resolution of 720 × 576 pixels, the Zeiss FF 450 camera performed better in only two of the subscales – noise (p = 0.001) and artefacts (p = 0.01). Lens opacities significantly influenced only the two subscales ‘resolution’ and ‘details’, which deteriorated with increasing media opacities for both imaging systems.Conclusions:  Distinct scales to grade image characteristics of different origin were developed and validated. Overall SDO digital imaging was found to provide fundus pictures of a similarly high level of quality as expert photography on slides.
Peripheral refraction for distance and near vision in emmetropes and myopes
Authors: Calver Richard , Radhakrishnan Hema , Osuobeni Ebi , O’Leary Daniel 
Published: October 2007

AbstractWe investigated the relationship between myopia and peripheral refraction for distance and near vision by measuring peripheral refractive errors in 10 myopic and 10 emmetropic participants at viewing distances of 2.5 and 0.4 m. Measurements were made at the fovea, and at eccentricities of 10°, 20° and 30° in the temporal and nasal hemispheres of the horizontal visual field. Our results showed that peripheral astigmatism increased with increasing eccentricity, but there was no significant difference between refractive error groups except at 30° eccentricity in the temporal retina. Considering the Mean Spherical Equivalent errors, emmetropes became relatively myopic at peripheral eccentricities, but there was little change in myopes. The effect of viewing distance on astigmatism or Mean Spherical Equivalent error was not significant. Our results do not support the view that myopia is associated with changes in peripheral refraction during distance or near vision.
The relationship between the treatment zone diameter and visual, optical and subjective performance in Corneal Refractive Therapy™ lens wearers1
Authors: Lu Fenghe , Simpson Trefford , Sorbara Luigina , Fonn Desmond 
Published: October 2007

AbstractPurpose:  To investigate the stability of the treatment zone (TZ) size during Corneal Refractive Therapy (CRT™) over 4 weeks of lens wear, and to determine the relationship between TZ diameter and visual, optical and subjective performance.Methods:  Twenty‐three myopic subjects wore CRT™ lenses overnight and removed their lenses on awakening. Visual Acuity (VA), subjective vision, refractive error, aberrations and corneal topography were measured at baseline, immediately after lens removal on the first day and 14 h later, and these measurements were repeated on days 4, 10 and 28. The TZ including the central flattened zone (CFZ) and the annular steepened zone (ASZ) was demarcated by the change in corneal curvature from negative to positive and vice versa, using the tangential difference map from the Atlas corneal topographer.Results:  After overnight CRT™ lens wear, the central cornea flattened and the mid‐periphery steepened (both p < 0.001). After 4 weeks of lens wear, the CFZ (±SE) increased from 3.41 ± 0.09 mm on day 1 morning to 3.61 ± 0.07 mm on day 28 morning and the diameter of the ASZ increased from 8.17 ± 0.16 mm (day 1 morning) to 8.85 ± 0.14 mm (day 28 morning) (both p < 0.001). From day 10 onwards, the CFZ and ASZ diameter were stable in the morning (p ≥ 0.404). Throughout the day, the CFZ became smaller during the first 10 days (all p ≤ 0.022), whereas the ASZ diameter remained constant (all p ≥ 0.079). There were positive correlations between the CFZ or ASZ and residual refractive error, subjective vision and spherical aberration. The CFZ was also correlated with astigmatism and higher order aberrations, and the ASZ was positively correlated with coma (r = 0.726 to 0.961, all p ≤ 0.042). In addition, there were negative correlations between the CFZ or ASZ and total aberration and defocus and between the ASZ and VA (r = −0.707 to −0.953, all p ≤ 0.050).Conclusion:  The TZ changed during the first 10 days. Its size was associated with VA, residual refractive error, aberrations and subjective vision. The concept of a TZ is a useful metric of visual, optical and subjective performance in CRT™ lens wearers.
Vision screening of older people
Authors: Jessa Zahra , Evans Bruce , Thomson David , Rowlands Gill 
Published: October 2007

AbstractA recent systematic review found that between 20% and 50% of older people in the UK have undetected reduced vision and in most cases this is caused by refractive error or cataracts, and is correctable. Two approaches to improve the detection of these problems are to better publicise optometric services and to carry out community‐based vision screening of older people. Screening programmes should pass the Wilson criteria and a consideration of these highlights three inter‐related questions: ‘Is vision screening effective at detecting correctable low vision in older people?’; ‘Which tests should be included?’ and ‘Which venues are most appropriate?’ We carried out a systematic review to investigate these questions.For the first question, only one study was found which met our selection criteria. The ‘gold standard’ eye examination in this study lacked several important components, and the vision screening method that was used was not found to be very effective. The review revealed other studies, which, although not meeting our selection criteria, included relevant information. The screening studies highlight the lack of agreement on the content of a gold standard eye examination and of the test(s) that should be used to screen vision.Visual function in older people is not adequately described by high contrast visual acuity (VA), nor by self‐reports of visual difficulties. Other tests that may be relevant include visual field testing, low contrast VA, contrast sensitivity and stereo‐acuity. The pinhole test has often been used in attempts to detect uncorrected refractive errors, but results from this test can be problematic and possible reasons for this are discussed. Appropriate venues for vision screening are contingent upon the format of the vision screening programme.There is still uncertainty over the battery of vision tests that are most appropriate. This, and optimum venues for screening, require further research before it can be fully determined whether vision screening of older people meets the Wilson criteria. If a vision screening programme using a battery of vision tests, perhaps computerised, can be established, then this should be tested to determine the sensitivity and specificity for detecting the target conditions. Ultimately, longitudinal studies are necessary to determine whether such a screening programme will lead to improved visual performance and quality of life in older people.
Estimating Health Conditions for Small Areas: Asthma Symptom Prevalence for State Legislative Districts
Authors: Mendez‐Luck Carolyn A. , Yu Hongjian , Meng Ying‐Ying , Jhawar Mona , Wallace Steven P. 
Published: October 2007

Research Objective. To create prevalence estimates of asthma symptoms for California legislative districts.Data Sources.
Three main data sources were used for this study: 2001 California Health Interview Survey, 2000 Census, and 2000–2002 March Current Population Surveys.Study Design. Secondary data analyses were conducted from cross‐sectional data to distribute the joint probability of ever having an asthma diagnosis and symptoms in the last 12 months within an Assembly district. We applied hierarchical logistic regressions to estimate the parameters for selected survey and census data that predicted the probabilities of diagnosed asthmatics with asthma symptoms. Predictors included individual‐level variables and contextual variables at zip code levels.Principal Findings. Asthma symptom prevalence geographically varied by age within and across Assembly districts throughout California.Conclusions. With modest investments in establishing analytic data files and estimating regression parameters for target conditions, small area estimation (SAE) procedures can create health data estimates not otherwise available at the sub‐county level. Applying SAE procedures to asthma symptom prevalence suggest that these data can become essential reference tools for advocates and policy makers currently addressing this and other public health concerns in the state.
Implications of the Medicaid Undercount in a High‐Penetration Medicaid State
Authors: Goidel R. Kirby , Procopio Steven , Schwalm Douglas , Terrell Dek 
Published: October 2007

Research Objective. This study investigates the impact of misreporting by Medicaid recipients on estimates of the uninsured in Louisiana, and is based on similar work by Call et al. in Minnesota and Klerman, Ringel, and Roth in California. With its unique charity hospital system, culture, and high poverty, Louisiana provides an interesting and unique context for examining Medicaid underreporting.Study Design. Results are based on a random sample of 2,985 Medicaid households. Respondents received a standard questionnaire to identify health insurance status, and individual records were matched to Medicaid enrollment data to identify misreporting.Data Sources. Data were collected by the Public Policy Research Lab at Louisiana State University using computer‐assisted telephone interviewing. Using Medicaid enrollment data to obtain contact information, the Louisiana Health Insurance Survey was administered to 2,985 households containing Medicaid recipients. Matching responses on individuals from these households to Medicaid enrollment data yielded responses for 3,199 individuals.Conclusions. Results suggest relatively high rates of underreporting among Medicaid recipients in Louisiana for both children and adults. Given the very high proportion of Medicaid recipients in the population, this may translate up to a 3 percent bias in estimates of uninsured populations.Implications. Medicaid bias may be particularly pronounced in areas with high Medicaid enrollments. Misreporting rates and thus the bias in estimates of the uninsured may differ across areas of the United States with important consequences for Medicaid funding.Funding Source. Louisiana Department of Health and Hospitals.
Examining Variation in Treatment Costs: A Cost Function for Outpatient Methadone Treatment Programs
Authors: Dunlap Laura J. , Zarkin Gary A. , Cowell Alexander J. 
Published: October 2007

Objectives. To estimate a hybrid cost function of the relationship between total annual cost for outpatient methadone treatment and output (annual patient days and selected services), input prices (wages and building space costs), and selected program and patient case‐mix characteristics.Data Sources. Data are from a multistate study of 159 methadone treatment programs that participated in the Center for Substance Abuse Treatment's Evaluation of the Methadone/LAAM Treatment Program Accreditation Project between 1998 and 2000.Study Design. Using least squares regression for weighted data, we estimate the relationship between total annual costs and selected output measures, wages, building space costs, and selected program and patient case‐mix characteristics.Principal Findings. Findings indicate that total annual cost is positively associated with program's annual patient days, with a 10 percent increase in patient days associated with an 8.2 percent increase in total cost. Total annual cost also increases with counselor wages (p<.01), but no significant association is found for nurse wages or monthly building costs. Surprisingly, program characteristics and patient case mix variables do not appear to explain variations in methadone treatment costs. Similar results are found for a model with services as outputs.Conclusions. This study provides important new insights into the determinants of methadone treatment costs. Our findings concur with economic theory in that total annual cost is positively related to counselor wages. However, among our factor inputs, counselor wages are the only significant driver of these costs. Furthermore, our findings suggest that methadone programs may realize economies of scale; however, other important factors, such as patient access, should be considered.
Gender Differences in Friends’ Influences on Adolescent Drinking: A Genetic Epidemiological Study
Authors: Dick Danielle M. , Pagan Jason L. , Holliday Candice , Viken Richard , Pulkkinen Lea , Kaprio Jaakko , Rose Richard J. 
Published: October 2007

Background:  We use data from a population‐based twin study to examine the association between characteristics of the friendship group and adolescents’ own alcohol use at age 14, with focus on gender differences, both with respect to the adolescent’s own gender and the gender composition of his/her friendship group.Methods:  (1) We conducted analyses on the full epidemiological sample of individuals to determine the magnitude of association between friendship characteristics and alcohol use, and to test for interaction with gender and gender of friends. (2) We used the twin structure of the dataset to study the extent to which similarity in drinking behaviors between adolescents and their friends was due to shared genetic and/or environmental pathways.Results:  Friends’ drinking, smoking, and delinquency were more strongly related to alcohol use in girls, compared to boys, and in adolescents with opposite‐sex friends, compared to adolescents with only same‐sex friends. Friends’ alcohol use showed modest evidence of genetic influence in girls, suggesting peer selection; however, there was no evidence of genetic influence on friends’ alcohol use in boys. The correlation between adolescent and friend drinking was largely attributable to shared environmental effects across genders.Conclusions:  Gender and gender of friends moderate the associations between friends’ behavior and adolescents’ alcohol use, with evidence that girls, and those with opposite‐sex friends, may be more susceptible to friends’ influence. Genetically informative analyses suggest that similarity in alcohol use between adolescents and their friends is mediated, at least partially, through environmental pathways.