bluuebunny/crossref_metadata_2025_split huggingface dataset:
Predicting Change in Academic Abilities After Conformal Radiation Therapy for Localized Ependymoma
Authors: Conklin Heather M. , Li Chenghong , Xiong Xiaoping , Ogg Robert J. , Merchant Thomas E. 
Published: August 2008

Purpose Conformal radiation therapy (CRT) aims to limit the highest radiation dose to the tissue volume at risk while sparing surrounding normal tissues. This study investigated whether treatment of childhood ependymoma with CRT would preserve cognitive function. Academic competence was chosen as the primary outcome measure given it is a measure of applied cognitive abilities in a child's natural setting. Patients and Methods Eighty-seven pediatric patients diagnosed with ependymoma received CRT in which doses ranging from 54.0 to 59.4 Gy were prescribed to the postoperative tumor bed with a 10-mm clinical target volume margin. Cognitive testing was conducted at the start of CRT, 6 months, and annually after the start of CRT. The median length of follow-up was 59.6 months. Academic testing included subtests from the Wechsler Individual Achievement Test (WIAT) and the Achenbach Child Behavior Checklist. Results Linear mixed models with random coefficients revealed a modest but significant decline in reading scores during follow-up (WIAT slope estimate −0.064 ± 0.028 points/month; P = .026). Math and spelling performance remained stable. Supratentorial tumor location and multiple surgeries were predictive of worse reading performance at CRT baseline. Male sex, longer symptomatic interval, pre-CRT chemotherapy, pre-existing endocrine deficiencies, hydrocephalus, and younger age at CRT (< 5 years) were predictive of a significant decline in reading scores over time. Conclusion CRT may result in better long-term cognitive outcomes when compared to conventional radiation therapy approaches. Reading appears more vulnerable than other academic skills and may decline over time despite stable intellectual functioning.
Performing Nondiagnostic Research Biopsies in Irradiated Tissue: A Review of Scientific, Clinical, and Ethical Considerations
Authors: Brown Aaron P. , Wendler David S. , Camphausen Kevin A. , Miller Franklin G. , Citrin Deborah 
Published: August 2008

Purpose Recent development of drugs that target specific pathways in tumors has increased scientific interest in studying drug effects on tumor tissue. As a result, biopsies have become an important part of many early-phase clinical trials. Performing nondiagnostic tumor biopsies raises technical and ethical concerns mostly related to the use of a potentially harmful procedure with no potential benefit to the patient. This issue is complicated by uncertainty about whether performing biopsies in irradiated fields adds significant risk. This article reviews the clinical, scientific, and ethical considerations involved in performing nondiagnostic tumor biopsies in competent adults for research purposes, with a focus on biopsies performed in the setting of therapeutic irradiation. Methods Clinical trials that performed biopsies during or within 4 months of the completion of radiotherapy were identified with a literature review. Results Twenty-nine studies with 2,160 patients were identified. Sixteen of 29 studies reported adverse events (AEs) but did not report active evaluation for biopsy complications. Ten studies did not mention AEs within the study report. At least three studies actively evaluated patients for biopsy complications. Taking this into consideration, 17 (>1%) of 2,160 patients were reported to have biopsy complications, although reporting of AEs was suboptimal in most studies. Conclusion Limited data suggest that biopsies can be performed in irradiated tissues without clinically significant excess risk. Ongoing and future trials including nondiagnostic research biopsies should record and report AEs related to this procedure to provide additional data on safety and toxicity.
Follow-up of pituitary tumor volume in patients with acromegaly treated with pegvisomant in clinical trials
Authors: Jimenez Camilo , Burman Pia , Abs Roger , Clemmons David R , Drake William M , Hutson Kent R , Messig Michael , Thorner Michael O , Trainer Peter J , Gagel Robert F 
Published: August 2008

ObjectiveWe examined pituitary tumor volumes in patients treated with pegvisomant for 18 months or longer, and in whom the tumors were monitored for at least 3 years. We present details on 9 of 304 patients in clinical trials with pegvisomant who experienced tumor growth within the first year of treatment.MethodMagnetic resonance images prior to start of pegvisomant and at last follow-up were examined in 43 patients (14% of participating patients). Twenty-nine had received prior radiation therapy (18% of irradiated patients) and all but five received somatostatin analogs between periods of pegvisomant treatment.ResultsAt follow-up, the median tumor volume was 0.6 cc (range 0.0–19.7 cc), in comparison with 1.6 cc (0.0–19.7 cc) at baseline (P<0.001). Twenty-five patients, of which 23 received radiation therapy, had tumor volume reduction. Seventeen patients had no significant change. One patient, who had not received radiation therapy, had an increase in tumor volume from 1.61 to 1.93 cc. Of the nine patients with tumor growth, six had progressive growth before initiating pegvisomant. Two patients with stable tumors while on octreotide experienced enlargement after octreotide discontinuation but remained stable on long-term pegvisomant therapy.ConclusionThe present data indicate that pegvisomant does not promote tumor growth and suggest that the nine observed cases of tumor progression, which occurred within 8 months after commencing pegvisomant, are likely rebound expansions after discontinuation of somatostatin analogs and/or the natural history of aggressively growing pituitary tumors. Continued long-term surveillance of tumor volume, particularly in non-irradiated patients, is recommended.
Clinical use of cabergoline as primary and adjunctive treatment for acromegaly
Authors: Moyes V J , Metcalfe K A , Drake W M 
Published: August 2008

BackgroundCabergoline is a dopamine agonist that may be used as primary or adjunctive therapy for acromegaly. Although one study suggested biochemical control may be achieved in a substantial proportion of patients, it is still commonly perceived to be a relatively ineffective treatment.Design and methodA prospective audit was performed of 15 consecutive acromegalic patients (eight males, seven females, median age 55, range 31–92 at presentation) treated with cabergoline to determine the effective dose and tolerability. All had normal anterior pituitary function; two patients had hyperprolactinaemia. Magnetic resonance imaging revealed nine adenomata, two partially empty sellae and four structurally normal pituitary glands. Nine patients had undergone transsphenoidal surgery 1–12 months, and one patient had received pituitary radiotherapy 18 years, prior to commencement of cabergoline. All patients had biochemical GH excess; median serum IGF1 471 ng/ml, range 239–746 ng/ml. The calculated mean of a series of GH measurements ranged from 2.7–45.8 mIU/l, median 9.7 mIU/l.ResultsOn a median weekly dose of cabergoline of 1.75 mg (range 0.5–7 mg) normalisation of both IGF1 and GH occurred in 4 out of the 15 patients (27%). Out of the 15 patients (33%), 5 achieved a serum IGF1 within the reference range with notable reductions seen in a further five patients. Nine patients (60%) achieved a mean serum GH level of less than 5 mIU/l. Duration of treatment was 2–52 months and was well tolerated in 14 patients.ConclusionCabergoline can be an effective and well tolerated primary or adjunctive therapy for acromegaly and useful clinical responses are noted even with modest doses.
Sex steroids in androgen-secreting adrenocortical tumors: clinical and hormonal features in comparison with non-tumoral causes of androgen excess
Authors: d'Alva Catarina B , Abiven-Lepage Gwenaelle , Viallon Vivian , Groussin Lionel , Dugue Marie Annick , Bertagna Xavier , Bertherat Jerôme 
Published: August 2008

ObjectiveAdrenocortical tumors (ACT) account for no more than 0.2% of the causes of androgen excess (AE). Conversely, these rare tumors have a very poor prognosis. It is difficult and important to exclude this diagnosis whenever there is AE.DesignRetrospective investigation of androgen profiles in a large consecutive series of androgen-secreting (AS) ACT to assess their relative diagnostic value.MethodsA total of 44 consecutive female patients with ACT-AS and a comparison group of 102 women with non-tumor causes of AE (NTAE).ResultsPatients with ACT-AS were older than the ones with NTAE (37.7 vs 24.8 years; P<0.001) and the prevalence of hirsutism, acne, and oligo/amenorrhea were not different. Free testosterone was the most commonly elevated androgen in ACT-AS (94%), followed by androstenedione (90%), DHEAS (82%), and total testosterone (76%), and all three androgens were simultaneously elevated in 56% of the cases. Androgen serum levels became subnormal in all ACT-AS patients after complete tumor removal. In NTAE, the most commonly elevated androgen was androstenedione (93%), while all three androgens were elevated in only 22% of the cases. Free testosterone values above 6.85 pg/ml (23.6 pmol/l) had the best diagnostic value for ACT-AS (sensitivity 82%, confidence interval (CI): 57–96%; specificity 97%, CI: 91–100%). Basal LH and FSH levels were significantly lower in the ACT-AS group.ConclusionFree testosterone was the most reliable marker of ACT-AS. However, the large overlap of androgen levels between ACT-AS and NTAE groups suggests that additional hormonal and/or imaging investigations are required to rule out ACT-AS in case of increased androgens.
Zero-Inflated Modeling of Fish Catch per Unit Area Resulting from Multiple Gears: Application to Channel Catfish and Shovelnose Sturgeon in the Missouri River
Authors: Arab Ali , Wildhaber Mark L. , Wikle Christopher K. , Gentry Casey N. 
Published: August 2008

Abstract
Fisheries studies often employ multiple gears that result in large percentages of zero values. We considered a zero-inflated Poisson (ZIP) model with random effects to address these excessive zeros. By employing a Bayesian ZIP model that simultaneously incorporates data from multiple gears to analyze data from the Missouri River, we were able to compare gears and make more year, segment, and macrohabitat comparisons than did the original data analysis. For channel catfish Ictalurus punctatus, our results rank (highest to lowest) the mean catch per unit area (CPUA) for gears (beach seine, benthic trawl, electrofishing, and drifting trammel net); years (1998 and 1997); macrohabitats (tributary mouth, connected secondary channel, nonconnected secondary channel, and bend); and river segment zones (channelized, inter-reservoir, and least-altered). For shovelnose sturgeon Scaphirhynchus platorynchus, the mean CPUA was significantly higher for benthic trawls and drifting trammel nets; 1998 and 1997; tributary mouths, bends, and connected secondary channels; and some channelized or least-altered inter-reservoir segments. One important advantage of our approach is the ability to reliably infer patterns of relative abundance by means of multiple gears without using gear efficiencies.
Efficiency of a Quadrat Sampling Technique for Estimating Riffle-Dwelling Crayfish Density
Authors: Larson Eric R. , DiStefano Robert J. , Magoulick Daniel D. , Westhoff Jacob T. 
Published: August 2008

Abstract
Quantitative sampling of crayfish can be challenging as a result of clustered distributions produced by a variety of factors. We tested the efficiency of a 1-m2 quadrat sampler for estimating the density of riffle-dwelling crayfish. Sampling efficiency was evaluated in an Ozark Plateau stream through a mark–recapture study. We stocked three marked crayfish per square meter into 12 enclosed riffle sections (range, 46–53 m2) and then randomly sampled five 1-m2 quadrats in each of the 12 sections. Sampling efficiency was determined by comparing the estimates of crayfish density to the known density of marked crayfish. We found crayfish sampling efficiency (mean, 69%) to be comparable to that in studies evaluating the quadrat sampler for stream fish, although efficiency across our study riffles ranged widely, from large underestimates (27%) to positively biased overestimates (140%). Coefficients of variation revealed that replicating habitat units within a stream or stream reach may provide more precise crayfish density estimates than replicating quadrat samples within a single habitat unit. None of the physical habitat or water chemistry variables that we measured were correlated with sampling efficiency. A power analysis of confidence interval (CI) precision demonstrated that moderate precision (i.e., CI half-width = 20% of mean) was achievable at a reasonable sampling effort (40 quadrats). The 1-m2 quadrat sampler can be effective for quantitatively sampling lotic crayfish. This information should benefit researchers and managers interested in estimates of crayfish density in streams.
Crappie Hybridization in Southern Minnesota Lakes and Its Effects on Growth Estimates
Authors: Miller Loren M. , McInerny Michael C. , Roloff Jason 
Published: August 2008

Abstract
Species-specific microsatellite DNA markers were used to identify hybrids of black crappies Pomoxis nigromaculatus and white crappies P. annularis and to determine the effect of hybridization on crappie growth. Specifically, we determined the contribution of hybrids to the skew in length frequency distributions that is frequently observed within year-classes of sympatric crappie populations and the resulting upward bias on growth estimates for the two species. Hybridization was found throughout most southern Minnesota lakes that contained both species, but the frequency of hybrids was low in our length-stratified subsamples (mean frequency of first-generation (F1) hybrids among all lakes and year-classes = 3.2%; mean frequency of advanced-generation (Fx) hybrids = 1.4%). Among the 22 study lakes, only 2 contained no hybrids (based on polymerase chain reaction amplification of microsatellite loci). The F1 hybrids were disproportionately classified as black crappies under a Minnesota Department of Natural Resources (MNDNR) classification system that only allowed assignment of crappies to the two parental species. In one lake sampled over multiple years, we found F1 hybrids in only 5 of 14 year-classes of MNDNR-classified black crappies and in 4 of 11 year-classes of MNDNR-classified white crappies, indicating annual variation in the prevalence of hybridization. Consistent with their faster growth and tendency to be classified as black crappies, F1 hybrids accounted for 82% of all statistical outliers in length distributions of MNDNR-classified black crappie age-classes and 33% of the infrequent outliers in MNDNR-classified white crappie age-classes. The presence of F1 hybrids in our subsamples produced an upward bias in back-calculated length estimates for black crappies but had nonsignificant effects on white crappie length estimates. The effects of hybridization should be taken into account when estimating growth in crappie species from sympatric populations.
Water-Level Fluctuation Effects on Centrarchid Reproductive Success in Reservoirs: A Modeling Analysis
Authors: Clark Mark E. , Rose Kenneth A. , Chandler James A. , Richter Tracy J. , Orth Donald J. , Van Winkle Webster 
Published: August 2008

Abstract
An individual-based model of nesting smallmouth bass Micropterus dolomieu and white crappie Pomoxis annularis is used to compare reproductive success in a deep reservoir and a shallow reservoir under different amplitudes and periods of water-level fluctuations. The model simulates nest site selection, egg deposition, and the subsequent development and survival of young from eggs through dispersal in a two-dimensional spatial grid of habitat cells representing the reservoir bottom. All simulations are for May through September using a daily time step. Nest site (cell) selection is determined from species-specific habitat suitability indices based on substrate, slope, depth, and structure. The development of the young is temperature dependent. Mortality occurs via attrition, abandonment, and whole-nest catastrophe. Model corroboration was performed with observations of nesting white crappies and smallmouth bass in Brownlee Reservoir, Idaho–Oregon. The predicted egg-to-dispersal survival declined with increasing amplitude similarly for both species and more sharply in the shallow reservoir. The minimum survival across periods tended to occur at a period of about 5 d for white crappies but at about 10 d for smallmouth bass, which coincided with the early life stage developmental times for both species. The highest survival for both species occurred at a low amplitude and short period in the deep reservoir, while white crappie survival generally increased and smallmouth bass survival decreased with increasing period and amplitude in the shallow reservoir. We generalize our modeling results to centrarchids and suggest that the duration of key early life stages should be matched with the period and amplitude of water-level fluctuations to maximize survival and that in some situations, trade-offs between species survival rates will complicate management.
Initial Mortality and Retention Associated with Using Passive Integrated Transponders in Black Crappies
Authors: Isermann Daniel A. , Carlson Andrew J. 
Published: August 2008

Abstract
We assessed initial retention and mortality associated with using passive integrated transponders (PITs) for marking black crappies Pomoxis nigromaculatus by conducting 48-h net-pen trials (N = 4 trials) in April–May 2007 and one 14-d trial in October 2007. Black crappies (N = 175; total length (TL) range = 175–328 mm; mean TL = 265 mm; SE = 2.1 mm) were captured from a Minnesota lake by boat electrofishing or angling. Before being placed in the net-pen, each fish received one of four treatments: (1) a 12-mm PIT, (2) a left pectoral fin clip, (3) a PIT and a fin clip, and (4) no fin clip or PIT (i.e., reference fish). We injected PITs posterior to the pelvic girdle using a 12-gauge hypodermic needle. Average water temperature during trials ranged from 10.5°C to 16°C. No fish died and no PITs were shed during the 48-h trials. All PITs were retained during the 14-d trial in October, but 5 of the 42 black crappies died between days 12 and 14. None of the dead fish belonged to the PIT-only treatment. Mortality was probably the result of net-pen confinement, but four of the five mortalities had received a fin clip. Black crappies that retained PITs were filleted, and all PITs were observed to remain outside the typical range of meat removed by anglers for consumption. We conclude that PITs applied in this manner were initially safe (i.e., were not consumed in fillets), were effective (i.e., 100% retention), and did not increase initial mortality of black crappies at these water temperatures. Depending on fin regeneration rates, fin clips might serve as an effective secondary mark for assessing PIT retention in black crappies over certain periods of time, but mortality associated with fin-clipping should be assessed to ensure that mortality rates are low.
Catch Rates and Selectivity among Three Trap Types in the U.S. South Atlantic Black Sea Bass Commercial Trap Fishery
Authors: Rudershausen Paul J. , Baker M. Scott , Buckel Jeffrey A. 
Published: August 2008

Abstract
We compared selectivity and catch rates of black sea bass Centropristis striata between two experimental trap types: back-panel traps (50.8-mm-mesh back panels; 38.1-mm mesh in all other panels), which represent the new legal minimum mesh configuration; and all-panel traps (50.8-mm mesh in all panels), which are electively used by a subset of fishers. Catches in both experimental trap types were compared with catches in control traps (38.1-mm mesh in all panels). Traps were fished from October 2006 to March 2007 in waters 12–30 m deep in Onslow Bay, North Carolina. Correlation analyses were used to examine postrelease condition of discarded black sea bass in relation to fish density in traps and capture depth. We found that mean catch rates of sublegal-sized black sea bass (&lt;254 mm total length) were lower for control traps than for both experimental traps and were lower for back-panel traps than for all-panel traps; however, catch rates of legal-sized fish were not different among trap types. Median black sea bass size increased with trap mesh size. Modeled selectivity for each experimental trap type was relatively knife-edged (i.e., characterized by a narrow selection range); both experimental trap types caught smaller proportions of sublegal-sized fish and higher proportions of legal-sized fish than did control traps. Estimated immediate mortality rates of black sea bass discards were 3.7 (control), 1.1 (back panel), and 0.7% (all panel). Less-favorable release condition was positively correlated with fish density and depth. Combining immediate discard mortality over observed depths (common depths for this fishery) and losses from observable barotrauma, the assumed mortality rate of discarded black sea bass in the U.S. South Atlantic commercial trap fishery (15%) may be too high.
Distribution of Genetically Differentiated Splittail Populations during the Nonspawning Season
Authors: Baerwald Melinda R. , Feyrer Frederick , May Bernie 
Published: August 2008

AbstractGenetic assignment of individuals to their population of origin has many management applications, such as forensic identification of protected species, estimation of migration rates, mixed‐stock analysis, and assessment of hybridization. In this study, microsatellite markers were used to obtain an overview of population structure and foraging distribution patterns for a migratory cyprinid, the splittailPogonichthys macrolepidotus. We (Baerwald et al. 2007) recently discovered that splittail inhabiting the San Francisco Estuary form two genetically distinct populations, the Petaluma‐Napa and Central Valley populations, and individuals reassigned back to their respective populations with high accuracy (98%). In the present study, we genotyped 242 age‐0 splittail from previously unexamined locations in Suisun Marsh and the Sacramento‐San Joaquin Delta to determine whether they belonged to one of the two established populations or to a yet‐unknown population; we also assigned foraging adults to their population of origin to determine whether they exhibited overlapping or segregated distribution patterns during the nonspawning season. We determined that these fish were members of the two established populations. Both populations foraged in Suisun Bay during the nonspawning season, whereas Suisun Marsh was almost exclusively used by the Central Valley population. The Petaluma‐Napa population was considerably more abundant in the western portion of Suisun Bay and appeared to preferentially forage closer to its spawning grounds. The results indicate that the distributions of the two splittail populations do not entirely overlap during spawning and foraging; this finding has important implications for the conservation and management of the species.