bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cost-effectiveness analysis of endovascular versus neurosurgical treatment for ruptured intracranial aneurysms in the United States
Authors: Maud Alberto , Lakshminarayan Kamakshi , Suri M. Fareed K. , Vazquez Gabriela , Lanzino Giuseppe , Qureshi Adnan I. 
Published: January 2009

Object
The results of the International Subarachnoid Aneurysm Trial (ISAT) demonstrated lower rates of death and disability with endovascular treatment (coiling) than with open surgery (clipping) to secure the ruptured intracranial aneurysm. However, cost-effectiveness may not be favorable because of the greater need for follow-up cerebral angiograms and additional follow-up treatment with endovascular methods. In this study, the authors' goal was to compare the cost-effectiveness of endovascular and neurosurgical treatments in patients with ruptured intracranial aneurysms who were eligible to undergo either type of treatment.

Methods
Clinical data (age, sex, frequency of retreatment, and rebleeding) and quality of life values were obtained from the ISAT. Total cost included those associated with disability, hospitalization, retreatment, and rebleeding. Cost estimates were derived from the Premier Perspective Comparative Database, data from long-term care in stroke patients, and relevant literature. Incremental cost-effectiveness ratios (ICERs) were estimated during a 1-year period. Parametric bootstrapping was used to determine the uncertainty of the estimates.

Results
The median estimated costs of endovascular and neurosurgical treatments (in US dollars) were $45,493 (95th percentile range $44,693–$46,365) and $41,769 (95th percentile range $41,094–$42,518), respectively. The overall quality-adjusted life years (QALY) in the endovascular group was 0.69, and for the neurosurgical group it was 0.64. The cost per QALY in the endovascular group was $65,424 (95th percentile range $64,178–$66,772), and in the neurosurgical group it was $64,824 (95th percentile range $63,679–$66,086). The median estimated ICER at 1 year for endovascular treatment versus neurosurgical treatment was $72,872 (95th percentile range $50,344–$98,335) per QALY gained. Given that most postprocedure angiograms and additional treatments occurred in the 1st year and the 1-year disability status is unlikely to change in the future, ICER for endovascular treatment will progressively decrease over time.

Conclusions
Using outcome and economic data obtained in the US at 1 year after the procedure, endovascular treatment is more costly but is associated with better outcomes than the neurosurgical alternative among patients with ruptured intracranial aneurysms who are eligible to undergo either procedure. With accrual of additional years with a better outcome status, the ICER for endovascular coiling would be expected to progressively decrease and eventually reverse.
The predictive value of low–field strength magnetic resonance imaging for intraoperative residual tumor detection
Authors: Hirschl Robert A. , Wilson Jeff , Miller Brandon , Bergese Sergio , Chiocca E. Antonio 
Published: January 2009

Object
Neurosurgeons have been utilizing intraoperative MR (iMR) imaging to evaluate the extent of tumor resection since the 1990s. A low–field strength (0.12 T) MR imaging unit (PoleStar N20, Medtronic) is a practical and relatively inexpensive iMR imaging system that has found increased use in neurosurgery. The gold standard for postoperative detection of residual tumor has been high-strength MR imaging performed within 48 hours of resection. The object of this study was to determine the predictive concordance of low-strength iMR imaging with standard high-strength MR imaging for detection of residual tumor.

Methods
The authors retrospectively evaluated the MR images from 74 intracranial tumor resections, comparing the intraoperative images obtained using a 0.12-T iMR imaging unit to the immediate postoperative images obtained using a standard 1.5-T MR imaging unit within 48 hours after surgery.

Results
The sensitivity of low-field MR imaging for detection of residual tumor was 0.74 (95% CI 0.58–0.86), and its specificity was 0.97 (95% CI 0.83–1). When only glial tumors (42 of the 74 lesions) were analyzed, the sensitivity was 0.82 (95% CI 0.59–0.94) and the specificity was 0.95 (95% CI 0.73–1).

Conclusions
These data could assist the neurosurgeon who has to decide intraoperatively whether the observed iMR images show residual tumor or not.
Malaria in southeast Bangladesh: A descriptive study
Authors: Maude Richard J. , Dondorp A.M. , Faiz M.A. , Yunus Emran Bin , Samad R. , Hossain Amir , Rahman M. Ridwanur 
Published: January 2009

Malaria in Asia is thought to be grossly under-reported and this is evident from previously published statistics from Bangladesh. Malaria screening data from four Upazillas was analysed alongside census data to assess the trends in malaria incidence over time and distribution of malaria by age and gender. Malaria incidence in this area has decreased by around two thirds since 2003, although control measures were not significantly increased until 2005.Â Malaria occurred in people of all ages with the highest incidence being in young adults. This is consistent with higher occupational exposure in this group. The probability of being screened for malaria decreased with age suggesting significant numbers of adults with malaria may be being missed.Keywords: Bangladesh; MalariaOnline: 29-1-2009DOI: 10.3329/bmrcb.v34i3.1757Bangladesh Med Res Counc Bull 2008; 34: 87-89
Major post-operative complications of thyroid surgery: Preventable or not?
Authors: Majid M.A. , Siddique Md. Ibrahim 
Published: January 2009

Factors responsible for major complications following thyroid surgery in 598 patients were studied. Patients with non toxic multinodular goiter involving both lobes of thyroid constituted the maximum bulk subjected to thyroidectomy. The most frequent procedure was bilateral subtotal thyroidectomy. Reactionary hemorrhage occurred in 6 patients, all following bilateral procedures and among them 5 patients developed tension hematoma with respiratory obstruction despite the presence of a drain. Temporary vocal cord palsy was observed in 7 patients whereas one patient subjected to total thyroidectomy with neck dissection for papillary carcinoma of thyroid developed permanent right vocal cord palsy. Temporary parathyroid insufficiency was seen in 51 patients and one patient developed permanent hypoparathyroidism. Incidence of parathyroid insufficiency was higher in bilateral procedures as compared to unilateral ones. There was no operation related death in this series, but complications like hemorrhage, vocal cord palsy and parathyroid insufficiency following thyroid surgery are still a deep concern. Keywords: Complication; Post-operative; Thyroid surgeryOnline: 29-1-2009DOI: 10.3329/bmrcb.v34i3.1973Â Â Â Â Â Bangladesh Med Res Counc Bull 2008; 34: 99-103.Â
Evolution of Neurotoxins: From Research Modalities to Clinical Realities
Authors: Kostrzewa Richard M. 
Published: January 2009

AbstractIn the 1950s, the discovery of anti‐nerve growth factor, an immunotoxin stunting sympathetic neural development, signaled the advent of neurotoxins as research modalities. Other selective neurotoxins were discovered in rapid succession. In the 1960s, 6‐hydroxydopamine and 6‐hydroxydopa were shown to destroy noradrenergic and dopaminergic nerves. Excitotoxins (glutamate, aspartate, and analogs) were discovered in the 1970s. DSP‐4 [N‐(2‐chloroethyl)‐N‐ethyl‐2‐bromobenzylamine] proved to be selective for noradrenergic destruction, while 5,6‐ and 5,7‐dihydroxytryptamines were relatively selective for serotonin neurons. Additional neurotoxins were discovered, but it was MPTP (1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine) that predominated neurotoxicity research in the 1980s. Eventually,Clostridium botulinumneurotoxin (BoNT), discovered as a “poisonous” principle in the late 1800s, resurfaced in purified and standardized forms as a clinically useful drug. Neurotoxins represent chemical tools, useful not only for discerning neuronal mechanisms and animal modeling of neurological disorders, but also for their use in medicine and potential as treatments for medical disorders. This unit reviews the early discovery of neurotoxins, describes categories of neurotoxins, and finally characterizes their usefulness—first as research tools, and eventually as clinical therapeutic agents.Curr. Protoc. Neurosci. 46:1.18.1‐1.18.10. © 2009 by John Wiley & Sons, Inc.
Use of Mouse Models for the Analysis of Human Disease
Authors: Semsarian Christopher 
Published: January 2009

AbstractThe first half of this unit discusses the two main approaches to developing genetically engineered mouse models of human disease (i.e., transgenesis and gene targeting). The experimental steps for each method are discussed. Potential pitfalls, advantages, and limitations are also addressed. The second half of the unit describes two mouse models of hypertrophic cardiomyopathy, which illustrate the value of studying such models of human disease, both in terms of understanding disease pathogenesis as well as potential new therapeutic avenues. Curr. Protoc. Hum. Genet. 60:15.2.1‐15.2.10. © 2009 by John Wiley & Sons, Inc.
Human iPS Cell Derivation/Reprogramming
Authors: Park In‐Hyun , Daley George Q. 
Published: January 2009

AbstractThis unit describes a protocol for deriving induced pluripotent stem (iPS) cells from human fibroblast cells. Human fibroblast cells are infected with retroviral vectors expressing four transcription factors (Oct4, Sox2, Klf4, and Myc) and selected for 3 to 4 weeks under human embryonic stem (hES) cell culture conditions. iPS cell colonies are mechanically isolated using a dissection microscope and handled like hES cells thereafter. Human iPS cells share similarities with hES cells including the expression of pluripotency genes, and differentiation as embryoid bodies in vitro into three germ layers (EB) and in vivo as teratomas. Curr. Protoc. Stem Cell Biol. 8:4A.1.1‐4A.1.8. © 2009 by John Wiley & Sons, Inc.
Visual acuity in the cathemeral strepsirrhine Eulemur macaco flavifrons
Authors: Veilleux Carrie C. , Christopher Kirk E. 
Published: January 2009

AbstractStudies of visual acuity in primates have shown that diurnal haplorhines have higher acuity (30–75 cycles per degree (c/deg)) than most other mammals. However, relatively little is known about visual acuity in non‐haplorhine primates, and published estimates are only available for four strepsirrhine genera (Microcebus, Otolemur, Galago, and Lemur). We present here the first measurements of visual acuity in a cathemeral strepsirrhine species, the blue‐eyed black lemur (Eulemur macaco flavifrons). Acuity in two subjects, a 3‐year‐old male and a 16‐year‐old female, was assessed behaviorally using a two‐alternative forced choice discrimination task. Visual stimuli consisted of high contrast square wave gratings of seven spatial frequencies. Acuity threshold was determined using a 70% correct response criterion. Results indicate a maximum visual acuity of 5.1 c/deg for the female (1718 trials) and 3.8 c/deg for the male (846 trials). These values for E. macaco are slightly lower than those reported for diurnal Lemur catta, and are generally comparable to those reported for nocturnal Microcebus murinus and Otolemur crassicaudatus. To examine ecological sources of variation in primate visual acuity, we also calculated maximum theoretical acuity for Cheirogaleus medius (2.8 c/deg) and Tarsius syrichta (8.9 c/deg) using published data on retinal ganglion cell density and eye morphology. These data suggest that visual acuity in primates may be influenced by activity pattern, diet, and phylogenetic history. In particular, the relatively high acuity of T. syrichta and Galago senegalensis suggests that visual predation may be an important selective factor favoring high visual acuity in primates. Am. J. Primatol. 71:343–352, 2009. © 2009 Wiley‐Liss, Inc.
The relation between Pearson's correlation coefficient r and Salton's cosine measure
Authors: Egghe Leo , Leydesdorff Loet 
Published: January 2009

AbstractThe relation between Pearson's correlation coefficient and Salton's cosine measure is revealed based on the different possible values of the division of the L1‐norm and the L2‐norm of a vector. These different values yield a sheaf of increasingly straight lines which together form a cloud of points, being the investigated relation. The theoretical results are tested against the author co‐citation relations among 24 informetricians for whom two matrices can be constructed, based on co‐citations: the asymmetric occurrence matrix and the symmetric co‐citation matrix. Both examples completely confirm the theoretical results. The results enable us to specify an algorithm that provides a threshold value for the cosine above which none of the corresponding Pearson correlations would be negative. Using this threshold value can be expected to optimize the visualization of the vector space.
The decline in the concentration of citations, 1900–2007
Authors: Larivière Vincent , Gingras Yves , Archambault Éric 
Published: January 2009

AbstractThis article challenges recent research (Evans, 2008) reporting that the concentration of cited scientific literature increases with the online availability of articles and journals. Using Thomson Reuters' Web of Science, the present article analyses changes in the concentration of citations received (2‐ and 5‐year citation windows) by papers published between 1900 and 2005. Three measures of concentration are used: the percentage of papers that received at least one citation (cited papers); the percentage of papers needed to account for 20%, 50%, and 80% of the citations; and the Herfindahl‐Hirschman index (HHI). These measures are used for four broad disciplines: natural sciences and engineering, medical fields, social sciences, and the humanities. All these measures converge and show that, contrary to what was reported by Evans, the dispersion of citations is actually increasing.
Insights into metabolic mechanisms underlying folate‐responsive neural tube defects: A minireview
Authors: Beaudin Anna E. , Stover Patrick J. 
Published: January 2009

AbstractNeural tube defects (NTDs), including anencephaly and spina bifida, arise from the failure of neurulation during early embryonic development. Neural tube defects are common birth defects with a heterogenous and multifactorial etiology with interacting genetic and environmental risk factors. Although the mechanisms resulting in failure of neural tube closure are unknown, up to 70% of NTDs can be prevented by maternal folic acid supplementation. However, the metabolic mechanisms underlying the association between folic acid and NTD pathogenesis have not been identified. This review summarizes our current understanding of the mechanisms by which impairments in folate metabolism might ultimately lead to failure of neural tube closure, with an emphasis on untangling the relative contributions of nutritional deficiency and genetic risk factors to NTD pathogenesis. Birth Defects Research (Part A) 2009. © 2009 Wiley‐Liss, Inc.
Review of published studies of kidney, liver, and gastrointestinal birth defects in fetal alcohol spectrum disorders
Authors: Hofer Ryan , Burd Larry 
Published: January 2009

AbstractOBJECTIVE: Review of published studies of birth defects of the renal, liver, and gastrointestinal organ systems in subjects with fetal alcohol spectrum disorders (FASD). METHOD: We searched PubMed (http://www.pubmed.gov) using the following terms: fetal alcohol syndrome and: gastrointestinal tract, kidney, liver, and congenital abnormalities for all years and English only citations. RESULTS: We located 12 studies of FASD and defects of or functional impairments for the liver, 12 of renal abnormalities, and only two with gastrointestinal defects. We did not identify specific patterns of malformations or functional deficits for any of the three organ systems. The existing literature suggests a series of nonspecific outcomes in FASD. CONCLUSIONS: Fetal alcohol spectrum disorder includes a diagnostic category of alcohol‐related birth defects which is clinically difficult to apply. This study adds to the existing literature on birth defects in FASD which is still very limited. The categorical diagnosis of alcohol‐related birth defects requires additional research to determine if a specific pattern of organ specific abnormalities or functional deficits emerges in subjects with FASD. Birth Defects Research (Part A), 2009. © 2009 Wiley‐Liss, Inc.
Zoonotic Ljungan virus associated with central nervous system malformations in terminated pregnancy
Authors: Niklasson Bo , Samsioe Annika , Papadogiannakis Nikos , Gustafsson Susanne , Klitz William 
Published: January 2009

AbstractBACKGROUND:The Ljungan virus (LV) has been shown to cause central nervous system malformations in laboratory mouse models. The LV has also been associated with intrauterine fetal death in humans. We investigated the presence of LV in a series of human hydrocephaly and anencephaly cases from elective abortions.METHODS:A series of elective abortions owing to hydrocephaly, anencephaly, and similarly aged trisomy 21 elective abortions as controls were examined for LV by immunohistochemistry and real time RT‐PCR. A second experiment involved newborn mice exposed to LV.RESULTS:LV was diagnosed in 9 of 10 cases with hydrocephalus and in 1 of 18 trisomy 21 controls by immunohistochemistry. Five of nine cases with anencephaly had a positive PCR result, whereas none of the 12 trisomy 21 available for PCR testing had a positive result. The 47 newborn mice exposed to LV all developed encephalitis, with eight having hydrocephalus. None of the 52 control animals had encephalitis or hydrocephalus.CONCLUSION:The association between LV and both hydrocephaly and anencephaly suggests that LV may be playing an important role in central nervous system malformations in humans. Birth Defects Research (Part A), 2009. © 2009 Wiley‐Liss, Inc.
Modeling fluid flow through irregular scaffolds for perfusion bioreactors
Authors: Maes Frédéric , Van Ransbeeck Peter , Van Oosterwyck Hans , Verdonck Pascal 
Published: January 2009

AbstractDirect perfusion of 3D tissue engineered constructs is known to enhance osteogenesis, which can be partly attributed to enhanced nutrient and waste transport. In addition flow mediated shear stresses are known to upregulate osteogenic differentiation and mineralization. A quantification of the hydrodynamic environment is therefore crucial to interpret and compare results of in vitro bioreactor experiments. This study aims to deal with the pitfalls of numerical model preparation of highly complex 3D bone scaffold structures and aims to provide more accurate wall shear stress (WSS) estimates. µCT imaging techniques were used to reconstruct the geometry of both a titanium (Ti) and a hydroxyapatite scaffold, starting from 430 images with a resolution of 8 µm. To tackle the tradeoff between model size and mesh resolution we selected two concentric regions of interest (cubes with a volume of 1 and 3.375 mm3, respectively) for both scaffolds. A flow guidance in front of the real inlet surface of the scaffold was designed to mimic realistic inlet conditions. With a flow rate of 0.04 mL/min perfused through a 5 mm diameter scaffold at an inlet velocity of 33.95 µm/s we obtained average WSSs of 1.10 and 1.46 mPa for the 1 mm3 and the 3.375 mm3 model of the hydroxyapatite scaffold compared to 1.40 and 1.95 mPa for the 1 mm3 model and the 3.375 mm3 model of the Ti scaffold, showing the important influence of the scaffold micro‐architecture heterogeneity and the proximity of boundaries. To assess that influence we selected cubic portions, of which the WSS data were analyzed, with the same size and the same location within both 1 and 3.375 mm3 cubic models. Varying the size of the inner portions simultaneously in both model selections gives a quantification of the sensitivity to boundary neighborhood. This methodology allows to get more insight in the complex concept of tissue engineering and will likely help to understand and eventually improve the fluid‐mechanical aspects. Biotechnol. Bioeng. 2009;103: 621–630. © 2009 Wiley Periodicals, Inc.
Production of recombinant HIV‐1 nef protein using different expression host systems: A techno‐economical comparison
Authors: Vermasvuori Raisa , Koskinen Jani , Salonen Katri , Sirén Noora , Weegar Jan , Dahlbacka John , Kalkkinen Nisse , von Weymarn Niklas 
Published: January 2009

AbstractThree popular expression host systemsEscherichia coli,Pichia pastorisandDrosophilaS2 were analyzed techno‐economically using HIV‐1 Nef protein as the model product. On scale of 100 mg protein, the labor costs corresponded to 52–83% of the manufacturing costs. When analyzing the cost impact of the different phases (strain/cell line construction, bioreactor production, and primary purification), we found that with the microbial host systems the strain construction phase was most significant generating 56% (E. coli) and 72% (P. pastoris) of the manufacturing costs, whereas with theDrosophilaS2 system the cell line construction and bioreactor production phases were equally significant (46 and 47% of the total costs, respectively). With different titers and production goal of 100 mg of Nef protein, the costs ofP. pastorisandDrosophilaS2 systems were about two and four times higher than the respective costs of theE. colisystem. When equal titers and bioreactor working volumes (10 L) were assumed for all three systems, the manufacturing costs of the bioreactor production of theP. pastorisandDrosophilaS2 systems were about two and 2.5 times higher than the respective costs of theE. colisystem. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Metabolic pathway analysis of glycerol metabolism in Klebsiella pneumoniae incorporating oxygen regulatory system
Authors: Zhang Qingrui , Xiu Zhilong 
Published: January 2009

AbstractIt is well known that environmental and genetic perturbations have major effects on the metabolic behavior of cells. In this work, a model that utilizes existing knowledge of oxygen and redox sensing/regulatory system to assist elementary flux modes (EFMs) has been developed and was carried out to predict the metabolic potential of Klebsiella pneumoniae for the production of 1,3‐propanediol (1,3‐PD) under anaerobic and aerobic conditions. It was found that the theoretical optimal 1,3‐PD yield could reach to 0.844 mol mol−1 if the pentose phosphate pathway (PPP), and transhydrogenase had a high flux under anaerobic condition. However, PPP had little influence on the theoretical 1,3‐PD yield, and the flux through tricarboxylic acid (TCA) cycle was high under aerobic conditions. In addition, the effect of oxygen level on the 1,3‐PD and biomass was further analyzed. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009