bluuebunny/crossref_metadata_2025 huggingface dataset:
Neural Stem Cell Targeting of Glioma Is Dependent on Phosphoinositide 3-Kinase Signaling
Authors: Kendall Stephen E. , Najbauer Joseph , Johnston Heather F. , Metz Marianne Z. , Li Shan , Bowers Marisa , Garcia Elizabeth , Kim Seung U. , Barish Michael E. , Aboody Karen S. , Glackin Carlotta A.
Published: March 2008

The utility of neural stem cells (NSCs) has extended beyond regenerative medicine to targeted gene delivery, as NSCs possess an inherent tropism to solid tumors, including invasive gliomas. However, for optimal clinical implementation, an understanding of the molecular events that regulate NSC tumor tropism is needed to ensure their safety and to maximize therapeutic efficacy. We show that human NSC lines responded to multiple tumor-derived growth factors and that hepatocyte growth factor (HGF) induced the strongest chemotactic response. Gliomatropism was critically dependent on c-Met signaling, as short hairpin RNA-mediated ablation of c-Met significantly attenuated the response. Furthermore, inhibition of Ras-phosphoinositide 3-kinase (PI3K) signaling impaired the migration of human neural stem cells (hNSCs) toward HGF and other growth factors. Migration toward tumor cells is a highly regulated process, in which multiple growth factor signals converge on Ras-PI3K, causing direct modification of the cytoskeleton. The signaling pathways that regulate hNSC migration are similar to those that promote unregulated glioma invasion, suggesting shared cellular mechanisms and responses.

Disclosure of potential conflicts of interest is found at the end of this article.
Breach design for managed realignment sites
Authors: Townend I. H.
Published: March 2008

In low-lying areas of the coast and particularly around estuaries, the option to realign some of the seawalls is becoming increasingly attractive. Although the wholesale removal of existing walls is possible in some cases, frequently this is not possible for a variety of reasons and it is necessary to consider simply breaching the existing wall over a limited length. In order to undertake this in a controlled manner the size of the breach needs to be determined in advance. Current guidance on breach design was derived from a regression analysis of data from sites on the east coast that have breached during storms. This provides a simple relationship between the tidal prism of the site and the breach width. The basis of this approach is re-examined and shown to have limited explanatory power. An alternative method is presented, which uses the basic flow conditions, a limiting threshold of erosion and a description of the site hypsometry (variation in area with level) to estimate the breach profile. The proposed method is tested using the east coast data for seawalls that have breached and shown to provide better estimates. As the basis of the method is quite general, it can be used in widely varying situations, allowing rough estimates to be made with the minimum of data, or more refined estimates when more site-specific information is available.
Effect of the Froude number on assessment of the bridge afflux
Authors: Seckin G. , Knight D. W. , Atabay S. , Seckin N.
Published: March 2008

This paper presents the findings of laboratory model testing of arch and straight-deck bridge constrictions, in a symmetrical compound channel flume having different roughness conditions. Four different types of bridge models, namely a single-opening, semicircular arch bridge, a multiple-opening, semicircular arch bridge, a single opening, elliptic arch bridge, and a straight-deck bridge with and without piers, were used in the testing programme. The validity of the Biery and Delleur method developed for the single cross-sectional-shaped arch bridge constrictions was examined for a compound channel case. The effect of different definitions of the Froude number on the application of the Biery and Delleur method was also investigated. The results showed that the Biery and Delleur method agreed reasonably well with the University of Birmingham data presented in the current study, provided that the Froude number was defined in the same way as originally envisaged. Significant errors may result, however, from using this method with definitions of the Froude number that are more appropriate to compound channels.
Longitudinal Change in Happiness during Aging: The Predictive Role of Positive Expectancies
Authors: Holahan Carole K. , Holahan Charles J. , Velasquez Katherine E. , North Rebecca J.
Published: March 2008

This study employed hierarchical linear modeling to document the time course of happiness across 20 years from average ages of 66 to 86 among 717 members of the Terman Study of the Gifted. In addition, the study examined the role of positive expectancies about aging, assessed at an average age of 61, in enhancing happiness in aging. The results showed a small decline in happiness over time. Higher age was associated with less happiness at baseline and with a greater decline in happiness. At the same time, the general level of happiness in this sample was moderately high, with a large majority of respondents relatively happy into later aging. Moreover, positive expectancies about aging, assessed at an average age of 61, predicted greater happiness at ages 70, 75, and 80. These results held controlling for prior happiness, as well as for prior self-rated health and income.
Rhyme and Reason: Developing Children's Understanding of Rhyme
Authors: Pramling Niklas , Carlsson Asplund
Published: March 2008

In this study, an extensive episode of teachers working with the intention of developing children's understanding of rhyme is analysed. The data for the analysis consist of a video-recording of two teachers and seven children (aged 3–5 years) working with a type of rhyme-card and trying to construct a poem. The analytical interest lies in the opportunities that the teachers provide children to develop a notion of rhyme. The result shows that what a rhyme is to large extent remains implicit in the talk. The critical distinction between a relation between words based on sound (i.e. a rhyme) and a relation between words based on sense also remains unverbalized. This means that while some children may discover this distinction themselves through participating in this activity and encountering a variety of examples, a child who has not understood this difference is not actually helped to do so. Relevance and implications of this study to the practice of preschool are briefly discussed.
Young Children's Access to Real Life: An Examination of the Growing Boundaries between Children in Child Care and Adults in the Community
Authors: Nimmo John
Published: March 2008

Young children in industrialized societies are increasingly separated from the everyday lives of adults in their community. This article explores the historical and cultural dynamics (and contradictions) of a growing boundary between children, particularly those in child care, and adults without primary care-giving roles. The article proposes that young children's participation in and contributions to a democratic society are rooted in access to this real life. The active role of children in the formation of social capital should be recognized by educators and policy makers as significant in the development of identity. A framework and strategies for developing meaningful child—adult relations in the context of child care are proposed as the basis for further research and practice.
‘Until the Cows Came Home’: Issues for Early Intervention Activities? Parental Perspectives on the Early Years Learning of Their Children with down Syndrome
Authors: Rix Jonathan , Paige-Smith Alice , Jones Helen
Published: March 2008

The article reports the views of parents of children with Down syndrome in the United Kingdom, and those of a parent-researcher, who have recently been or are currently involved in early intervention programmes. It reports on a series of semi-structured interviews with nine parents of eight children with Down syndrome and the reflective engagement of the parent-researcher. The parents reflect upon learning moments and activities with their child that have been most enjoyable, effective and easy to carry out, as well as those that were difficult or a potential cause of conflict. They also prioritise situations that had a positive impact upon their child's learning. This research adds a parental voice to evidence that suggests a need to place a greater emphasis on learning that comes from the child's interests and less upon developmental goals, and the positive impact this may have for both the parents and children currently being encouraged to engage in early intervention programmes.
Synthesis and characterization of azanonaborane-containing purine derivatives for boron neutron capture therapy
Authors: Genady Afaf , El-Zaria Mohamed , Gabel Detlef
Published: March 2008

Derivatives of purine, adenine, guanine, and 2,6-diaminopurine linked to the azanonaborane (B8N cluster) have been prepared, for possible use as powerful agents for boron neutron capture therapy (BNCT). The synthesis was carried out via a ligand exchange reaction. The exo-NH2R group of the azanonaborane of the type [(RH2N)B8H11NHR] can be exchanged by one hetero-nitrogen atom of the pyrimidine ring, and except for guanine, also by an N atom of the imidazole ring. The identity of the products was confirmed by NMR, elemental analysis, IR, and mass spectrometry. No reaction was found to occur with caffeine and theophylline under the same reaction conditions.
Textured nickel tapes prepared from commercially available material
Authors: Staller Oliver , Holzmann Dietmar , Gritzner Gerhard , Diko Pavel , Mikolaj Daniel , Kováč František
Published: March 2008

Textured Ni tapes were fabricated from commercially available nickel pellets (98.5% Ni). Ingots produced by a melt process were cold rolled to 150–400 μm thick tapes. Texturing was achieved by annealing in a reducing atmosphere (Ar + 6.5% v/v H2). Sharp cubic biaxial textured Ni tapes were obtained by thermal treatment at 1000°C for 2 hours in a reducing atmosphere. The tapes were characterized by scanning electron microscopy, X-ray diffraction and by electron backscattering diffraction. The tensile strength, the thermal expansion behavior and the Vickers hardness for the cold rolled tapes and for the heat-treated tapes were measured.
Surfactant-assisted polyol preparation of nickel powders with different morphologies
Authors: Şişman İlkay , Tütünoğlu Çağla , Aydın Ali
Published: March 2008

Sub-micrometer nickel powders of controlled size and morphology were produced by a surfactant-assisted polyol method, using ethylene glycol (EG) as solvent and reductant in the presence of sodium dodecyl sulfate (SDS) surfactant and NaOH. The resultant Ni powders were characterized by XRD, SEM, EDS, and FTIR. Spherical, hexagonal, and triangular fcc Ni powders from 0.30 to 0.60 μm were obtained in the presence of SDS; irregular spherical fcc Ni powders were obtained in its absence. The concentrations of SDS, NaOH and Ni(CH3COO)2·4H2O greatly influence the product morphology and size.
On the role of entanglement in Schrödinger’s cat paradox
Authors: Rinner Stefan , Werner Ernst
Published: March 2008

In this paper we re-investigate the core of Schrödinger’s “cat paradox”. We argue that one has to distinguish clearly between superpositions of macroscopic cat states |☺〉 + |☹〉 and superpositions of entangled states |☺, ↑〉 + |☹, ↓〉 which comprise both the state of the cat (☺=alive, ☹=dead) and the radioactive substance (↑=not decayed, ↓=decayed). It is shown, that in the case of the cat experiment recourse to decoherence or other mechanisms is not necessary in order to explain the absence of macroscopic superpositions. Additionally, we present modified versions of two quantum optical experiments as experimenta crucis. Applied rigorously, quantum mechanical formalism reduces the problem to a mere pseudo-paradox.
The Klein-Gordon equation with the Kratzer potential in d dimensions
Authors: Saad Nasser , Hall Richard , Ciftci Hakan
Published: March 2008

We apply the Asymptotic Iteration Method to obtain the bound-state energy spectrum for the d-dimensional Klein-Gordon equation with scalar S(r) and vector potentials V(r). When S(r) and V(r) are both Coulombic, we obtain all the exact solutions; when the potentials are both of Kratzer type, we obtain all the exact solutions for S(r) = V(r); if S(r) > V(r) we obtain exact solutions under certain constraints on the potential parameters: in this case, a possible general solution is found in terms of a monic polynomial, whose coefficients form a set of elementary symmetric polynomials.
Validity of Values for Metabolic Equivalents of Task During Submaximal All-Extremity Exercise and Reliability of Exercise Responses in Frail Older Adults
Authors: Mendelsohn Marissa E , Connelly Denise M , Overend Tom J , Petrella Robert J
Published: March 2008

Background and Purpose

Physical therapists and rehabilitation professionals in hospital and long-term care centers are using all-extremity semirecumbent exercise machines in their treatment programs. This study was undertaken to investigate the concurrent validity of values for software-generated metabolic equivalents of task (MET) from an all-extremity semirecumbent exercise machine and directly measured values for MET from a portable metabolic unit across a range of submaximal exercise intensities. A second purpose of this study was to determine the test-retest reliability of oxygen consumption and heart rate responses in older adults between standardized sessions of submaximal all-extremity aerobic exercise.

Subjects and Methods

The study participants were 18 older adults (mean age=82 years, SD=5; 3 women, 15 men) who were living in long-term care centers and who completed 2 test sessions of a standardized exercise protocol 1 week apart. The exercise protocol included a warm-up period, three 4-minute stages of exercise at incremental workload levels, and a cool-down period. The breath-by-breath metabolic data from the portable metabolic unit, heart rate, MET values from the exercise machine, Borg Rating of Perceived Exertion, and watts were recorded continuously throughout the exercise protocol.

Results

The concurrent validity of the MET values from the exercise machine and the portable metabolic unit ranged from very good to excellent on both day 1 and day 2 (r=.85–.97). The test-retest reliability of subjects' heart rate responses and MET values from the portable metabolic unit was moderate to high across submaximal exercise intensities (intraclass correlation coefficients [2,1]=.85–.91).

Discussion and Conclusion

The exercise machine software-generated MET values were representative of directly measured oxygen consumption values across a range of submaximal intensities during all-extremity semirecumbent exercise in older adults with multisystem impairments.
Internet and obstetrics and gynecology
Authors: Feingold Michael , Kewalramani Reshma , Kaufmann Gary E.
Published: March 2008

Background. The Internet is an unrestricted, easily accessed source of information that has been greatly touted by the mass media. It represents a major advance in information acquisition and dissemination. It is estimated that between 3(M‐0 million North Americans alone have access to the Internet. This multimedia reservoir of information has developed into a significant resource for information gathering, especially for those who depend on comprehensive and contemporary information, including scientists and physicians.

Methods and results. The purpose of this article is to describe some of the basic and practical services available on the Internet including e‐mail, literature searches, interest groups, databases and on‐line journals. Our focus is to describe these Internet resources with the physician in mind, and with particular emphasis on Internet applications for the obstetrician/gynecologist.

Conclusion. The role of the Internet in medicine has not been defined, but continues to evolve. In the field of obstetrics and gynecology, the Internet has already become incorporated in various ways and it is safe to say that we are currently going through a revolution as fundamental to the human civilization as the eighteenth century industrial revolution the information revolution.
Is a speculum examination sufficient for excluding the diagnosis of ruptured fetal membranes?
Authors: Ladfors Lars , Mattssoni Lars‐ÅKe , Eriksson Margareta , Fall Ole
Published: March 2008

Objective. To determine the false negative rate of a sterile speculum examination for the diagnosis of rupture of the membranes in women not in labor and without visible amniotic fluid at speculum examination. Furthermore, possible risks to the mother and the baby after suspected rupture of the membranes were analyzed.

Study design. In women not in labor with suspected rupture of the membranes between gestational weeks 34 and 42, a sterile speculum examination was performed. If no amniotic fluid was visible, a test for Diamine oxidase was carried out. The results of tests were not known to the obstetricians or the women. The women were allowed to return home with no further controls if no amniotic fluid was visible at the speculum examination. Neonatal and obstetric outcome was recorded prospectively.

Results. Of 27,502 deliveries, 2,099 women not in labor attended the delivery ward for suspected rupture of the membranes after week 34. Amniotic fluid was visualized in 1,580 women. In 519 women in whom no amniotic fluid was seen at the speculum examination, the Diamine oxidase test was negative in 456 and positive in 63. Antibiotics were given to eleven children (2.4 %) in the group with a negative Diamine oxidase and to one infant (1.6 %) in the positive Diamine oxidase group (p>0.05). No differences in obstetric outcome were recorded.

Conclusions. The false negative rate of a speculum examination for the diagnosis of rupture of the membranes in women without amniotic fluid visible at a speculum examination was 12 % when Diamine oxidase was used as the standard for the diagnosis of rupture of the membranes. This study did not show any disadvantages for mothers and infants if the women were sent home after a false negative speculum examination. The value of biochemical methods in the management of women not in labor with rupture of the membranes after thirty‐four weeks of gestation could be questioned.
Preterm premature rupture of membranes and the associated risk for placental abruption. Inverse correlation to gestational length
Authors: Holmgren Per Åke , Olofsson Jan I.
Published: March 2008

Objective. To evaluate the association between prolonged premature rupture of membranes (PROM) and placental abruption, especially during midtrimester pregnancy.

Methods. A retrospective hospital based study of 83 women with PROM occurring between 14 and 32 weeks of gestation and where active expectant management was undertaken. Results. Increased frequency of placental abruption was found in patients with early rupture of membranes. The incidence was 50% and 44% when rupture of the membranes occurred before 20 weeks or between 20‐24 weeks of pregnancy, respectively. When PROM occurred during gestational ages of 29‐32 weeks, the incidence was 13%. Patients with antepartum bleeding, both before (relative risk 34) and after rupture of the membranes (relative risk 38) had a significantly higher risk for placental abruption (p<.001) than women without bleeding prior to delivery. The overall neonatal survival rate was 87%. No neonatal deaths were considered to be directly caused by asphyxia due to placental abruption. Conclusion. Using active expectant management and strict routines it seems possible to minimize the risk for perinatal asphyxia and mortality. The clinician should be aware of the significant association between preterm premature rupture of membranes and the risk for subsequent placental abruption, especially in patients with early midtrimester PROM and history of bleedings before rupture of membranes or bleedings during the latency period.
Laparoscopic instillation of hyperosmolar glucose vs. expectant management of tubal pregnancies with serum hCG≤2500 mlU/mL
Authors: Lang Peter F. J. , Mäkinen Juha I. , Irjala Kerttu M. A. , Rantala Mika , Hönigl Werner , Tamussino Karl , Haas Josef
Published: March 2008

Objective. To compare expectant management with local instillation of 50% glucose solution for tubal pregnancies with a serum hCG level ≤2500 mlU/mL. Design. Prospective, non‐randomized, comparative clinical study.

Setting. Two university departments.

Patients. One hundred and twenty‐eight patients with laparoscopically‐confirmed tubal pregnancy and serum hCG ≤2500 mlU/mL.

Interventions. Eighty patients in Graz were treated with laparoscopic instillation of 50% glucose solution and 48 patients in Turku were followed expectantly.

Main outcome measures. Resolution of hCG excretion, need for further interventions.

Results. Seventy‐four of the 80 patients (92%) in the glucose group (32 of 33 with an initial hCG ≤250 mlU/mL and 42 of 47 with hCG 251‐2500 mlU/mL) and 36 of 48 (75%) patients in the expectant group (19 of 23 with an initial hCG ≤250 mlU/mL and 17 of 25 with hCG 251‐2500 mlU/mL) had resolution of the pregnancy with no further intervention (p=0.008, chi‐square test, odds ratio 0.24).

Conclusions. Glucose instillation is superior to expectant management for patients with early tubal pregnancy.
Underreporting and misclassification of maternal mortality in Taiwan
Authors: Kao Senyeong , Chen Li‐Mei , Shi Leiyu , Weinrich Martin C.
Published: March 2008

Background. Underreporting and misclassification of maternal deaths are universal. The purposes of this study were to quantify the level of underestimation of maternal mortality and to analyze possible factors that contribute to underreporting and misclassification of maternal mortality.

Methods. An interview census of all registered deaths that occurred during 1984‐1988 in women of reproductive age was undertaken in Taiwan. Pregnancy‐related deaths were screened from all collected questionnaires and death certificates by the researchers. The screened pregnancy‐related deaths were then reviewed and evaluated by obstetrician‐gynecologists; a cause of each death was assigned.

Results. For the five years, on average, the rate of underreporting of maternal mortality is 58.38% and the correct/confirmed rate of classification is 53.28%. Underreported and mis‐classified maternal deaths are more likely for women aged 20‐24, with stillbirth and fetal death, care sought for non‐obstetric reasons, care received in private hospitals and clinics, occurrence in the home, certification by non‐obstetrician‐gynecologists and court doctors, and death from non‐obstetric causes.

Conclusions. This study shows the limitations of official vital registration and concludes that dependence on death certificates alone to identify maternal deaths is incomplete and incorrect.
Pregnancy‐associated deaths in Finland 1987‐1994 ‐ definition problems and benefits of record linkage
Authors: Gissler Mika , Kauppila Riitta , Merilainen Jouni , Toukomaa Henri , Hemminki Elina
Published: March 2008

Background. Our aim was to study the impact of record linkage and different classification principles on maternal mortality rate.

Methods. The death certificates of all fertile‐aged women who died in 1987‐94 in Finland (n = 9,192) were linked to the Birth, Abortion, and Hospital Discharge Registers (n=513,472 births, 93,807 induced abortions, and 71,701 other ended pregnancies) to identify the women who had been pregnant during their last year of life. All deaths that occurred up to 1 year after the end of pregnancy were classified according to their connection to pregnancy. Results. In total, 281 qualifying deaths were found. Only in 22% of the death certificates was the pregnancy or its end mentioned. The mortality rate was 41 per 100,000 registered ended pregnancies (27 for births, 48 for miscarriages or ectopic pregnancies, and 101 for abortions). The maternal mortality rate depended greatly on which of these 281 cases were defined as maternal deaths. The early maternal mortality rate varied between 5.6 and 6.8 per 100,000 live births, and the late maternal mortality rate between 0.6 and 2.5 depending on the definition used. The classification of other than direct maternal deaths was ambiguous, especially in case of late cancers, cardio‐ and cerebrovascular diseases, and early suicides. The official Finnish figure for early maternal mortality (6.0/100,000 live births) seems to be a good estimate, although only 65% of individual deaths were unambiguously classified.

Conclusions. Register linkage is necessary to identify late maternal deaths and pregnancy‐associated deaths. The current official classification of maternal deaths as indirect, direct and fortuitous is arbitrary and allows much variation in defining a maternal death.
Infertility in an industrial setting:— a population‐based study from Northern Sweden
Authors: Wulff Marianne , Högberg Ulf , Stenlund Hans
Published: March 2008

Objective. To analyze the possible environmental effects on infertility among couples living in the immediate neighborhood of a smelter and to study prevalence and risk factors of infertility as well as care seeking behavior among infertile couples in a random sample of a local population.

Methods. A questionnaire was distributed to 1,784 women between 25 and 44 years of age working at or living close to a copper smelter, and to women living further away from the smelter. The results were analyzed with a logistic regression.

Results. No environmental effects on infertility rates among couples living near the smelter were found. The prevalence of infertility, defined as having experienced a period of inability to conceive within 12 months of regular intercourse without contraception at some point in life, was the same between the neighbors and the reference population. The prevalence of primary and secondary infertility was 6% and 3%, respectively. Infertile women were characterized by having a significantly shorter education, OR 1.8 (CI 1.2‐2.7), compared to women who had not experienced any fertility problems. Risk estimates for not seeking health care when having a low socio‐economic status was OR 2.1 (CI 1.0‐4.4) compared to those with a higher socio‐economic status.

Conclusion. No environmental effects on infertility could be demonstrated. Infertile women were characterized by having a shorter education compared to the non infertile, and women with lower socio‐economic status were less prone to seek help.
Comparison of ethacridine lactate and prostaglandin E2 in second trimester medical abortion
Authors: Inan Ismet , Kelekçi Sefa , Yazar Deniz
Published: March 2008

Background. A comparison of ethacridine lactate and prostaglandin E2 (PGE2) with or without oxytocin infusion in second trimester medical abortion cases.

Methods. A prospective study was performed on 151 women requiring second trimester medical abortions between 1989 and 1995. Patients were randomly assigned to PGE2 group (n= 30), ethacridine lactate group (n48), ethacridine lactate combined with oxytocin infusion group (n=49) and PGE2 combined with oxytocin infusion group (n=24). Rates of successful abortion (i.e., complete evacuation of fetal and placental tissxies from the uterus) within 24 hours for each group were determined and compared by x2 and the Student r‐test.

Results. Statistically significant difference concerning successful abortion rates was observed between ethacridine lactate and PGE2 groups, PGE2 and PGE2+oxytocin infusion groups, and ethacridine lactate+oxytocin infusion and PGE2 groups, while there was no significant difference between ethacridine lactate and ethacridine lactate+oxytocin infusion groups, ethacridine lactate and PGE2+oxytocin infusion groups, and PGE2+oxytocin infusion and ethacridine lactate+oxytocin infusion groups.

Conclusions. Extra‐amniotic ethacridine lactate instillation alone and intracervical PGE2 gel application are effective and safe methods for second trimester abortion.
Multiple induced abortions as risk factor for ectopic pregnancy
Authors: Skjeldestad Finn Egil , Gargiullo Paul M. , Kendrick Juliette S.
Published: March 2008

Objective. To assess the risk of ectopic pregnancy by the number of previous induced abortions.

Design. Prospective cohort study.

Methods. Three thousand seven hundred and fifty‐four women, 39 years old or younger, living permanently in one Norwegian county, who had had at least one induced abortion between January 1, 1987 and December 31, 1992, at the University Hospital of Trondheim, Norway were followed prospectively for histologically verified ectopic pregnancies until December 31, 1993. Exposure time was measured from the most recent induced abortion (index abortion) until the ectopic pregnancy, closure date, or the subject's 40th birthday. Statistical analyses were done in SAS applying survival analyses and poisson regression.

Results. During the follow‐up period of 164,167 women‐months, we observed 24 ectopic pregnancies in 3,754 women. The adjusted incidence density ratio (alDR) for women who had had two or more induced abortions was 1.2 (95% CI: 0.5‐3.1) in comparison with the reference group of women who had had one induced abortion. Measuring exposure as increasing number of consecutive induced abortions, no dose‐response to ectopic pregnancy was found between two consecutive (alDR 0.9) and three or more consecutive abortions (alDR 1.1) in comparison with the reference group.

Conclusion. In our setting, no excess risk of ectopic pregnancy was associated with multiple previous induced abortions compared with one previous induced abortion.
Subchronic Feeding Study of N,N-Dimethylformamide in Rats and Mice
Authors: Becci Peter J. , Voss Kenneth A. , Johnson William D. , Gallo Michael A. , Babish John G.
Published: March 2008

Wistar rats (25/ sex • group) and CD-1 mice (30/sex • group) were fed either a control diet or diet supplemented with N,N-dimethylformamide at the levels of 215, 750, and 2500 ppm for rats and 160,540, and 1850 ppm for mice. The duration of feeding was 104 days for rats and 119 days for mice. Body weight gain, food consumption, hematological and clinical chemical data, ophthalmic, gross, and microscopic examinations were used to study possible toxic or pathologic effects. A significant reduction in body weight gain was noted for male and female rats at the high dosage level. Food consumption in male rats at the high-dosage level and female rats at both the middle- and high-dosage levels was decreased. A significant dose-related increase in relative liver weights was noted in male and female rats. Absolute liver weights of male rats were comparable among groups, however, a dose-related increase was noted in female rats. No significant differences among groups were noted in body weight and food consumption data for mice. A significant dose-related increase in relative and absolute liver weights was noted in male and female mice. Histopathological evaluation revealed no evidence of a toxic effect related to feeding of N.N-dimethylformamide to Wistar rats and CD-1 mice. The increase in liver weight is considered to be a normal phenomenon (physiological adaptation) required for the biotransformation of N,N-dimethylformamide. The lack of hepatotoxicity in the present study may be the result of feeding N,N-dimethylf ormamide over waking hours versus bolus dosing (in other studies) in which hepatotoxicity was noted.
Carcinogenesis Bioassay of Propyl Gallate in F344 Rats and B6C3FJ Mice
Authors: Abdo K. M. , Huff J. E. , Haseman J. K. , Dieter M. P. , Boorman G. A. , Hildebrandt P. , Prejean J. D. , Farnell D. R.
Published: March 2008

Chronic toxicity studies were conducted by maintaining groups of 50 F344 rats and 50 B6C3F1 mice of each sex on nutritionally complete diets containing 0%, 0.6%, or 1.2% propyl gallate for 103 weeks. Survival of rats and mice of both sexes was not significantly affected by the administration of this compound. Dosed rats and mice showed growth retardation and reduced feed utilization efficiency. Increased incidence of hepatic cytoplasmic vacuolization and suppurative inflammation of the prostate gland were observed in dosed male rats and were considered to be related to propyl gallate administration. Tumors of the preputial gland, islet ceil tumors of the pancreas, and pheochromocytoma of the adrenal gland were observed with significantly (p < 0.05) higher incidence in the low-dose male rats; however, there was little evidence of a dose response or of an effect in the high-dose group. Rare tumors (an astrocytoma and a glioma) were found in the brains of two low-dose female rats but none was found in the high-dose group. Malignant lymphoma occurred with a significant (p < 0.05) positive trend in male mice and the incidence in the high-dose group was significantly (p < 0.05) higher than that of the concurrent controls. However, the high-dose incidence was not significantly different from the historical control rate for the laboratory that conducted the bioassay. Under the conditions of the bioassay, propyl gallate was not considered to be clearly carcinogenic for F344 rats, although the increased incidence of preputial gland tumors, islet-cell tumors of the pancreas, and pheochromocytoma of the adrenal glands in low-dose male rats may have been related to compound administration. Thus, the evidence for carcinogenicity in male rats is regarded as being equivocal, while there was no indication of a carcinogenic response in female rats. Propyl gallate was not considered to be carcinogenic for B6C3F1 mice, although the increased incidence of malignant lymphoma in dosed male mice may have been related to administration of the test compound.
A Female Rat Fertility Study with Inhaled Benzene
Authors: Kuna Robert A. , Nicolich Mark J. , Schroeder Raymond E. , Rusch George M.
Published: March 2008

Pure benzene was administered to female rats by inhalation at dose levels of 1, 10, 30, and 300 ppm for 6 h/day. The exposure took place during a 10-week premating period and during mating, gestation, and lactation periods. There was no effect on female reproductive performance. A trend toward reduced body and organ weights was observed in the 21-day-old pups at the 30 and 300 ppm dose levels. Except for reduced body and liver weights in the female pups at 300 ppm, these differences were not statistically significant. Kidney to body weight ratios for female pups were statistically higher than control values in the 10, 30, and 300 ppm exposure levels. These organ weights and organ-to-body weight ratio changes appear to have been reflective of differences in body weights. No treatment-related effects were seen in pup survival during lactation or in the gross postmortem evaluation of these pups on Day 21 of lactation. Thus exposure of dams to levels as high as 300 ppm resulted in only minimal effects on the pups. Study sponsored by U.S. manufacturers of benzene under the auspices of the Chemical Manufacturers Association and American Petroleum Institute (Ref. # BP 3.0).
Peroxisome Proliferation: A Biological Marker for Toxicological Evaluation
Authors: Reddy Janardan K. , Rao M. Sambasiva , Yeldandi Anjana V.
Published: March 2008

Peroxisome proliferators constitute an important group of xenobiotics with therapeutic, societal, and agricultural importance. Because these agents induce liver tumors in rodents, but fail to exert the genotoxic or mutagenic effects directly in short-term in vitro test systems, they are considered a paradigm to investigate the mechanisms of nongenotoxic hepatocarcinogenesis. A concerted cell biological, biochemical, and molecular biological approach is essential to understand the relationship of xenobiotic-induced peroxisome proliferation to the eventual development of liver tumors. It is our intent to provide insight into the mechanisms responsible for tissue specificity and species differences in the biological responses to peroxisome proliferators.
L2 Learner Production and Processing of Collocation: A Multi-study Perspective
Authors: Siyanova Anna , Schmitt Norbert
Published: March 2008

Abstract:

This article presents a series of studies focusing on L2 production and processing of adjective–noun collocations (e.g., social services). In Study 1, 810 adjective–noun collocations were extracted from 31 essays written by Russian learners of English. About half of these collocations appeared frequently in the British National Corpus (BNC); one-quarter failed to appear in the BNC at all, while another quarter had a very low BNC frequency. Based on frequency data and mutual information (MI) scores, it was discovered that around 45% of all learner collocations were, in fact, appropriate collocations, that is, frequent and strongly associated English word combinations. When the study data were compared to data from native speakers, very little difference was found between native speakers (NS) and non-native speakers (NNS) in the use of appropriate collocations. Unfortunately, the high percentage of appropriate collocations does not mean that NNSs necessarily develop fully native-like knowledge of collocation. In Study 2, NNSs demonstrated poorer intuition than NS respondents regarding the frequency of collocations. Likewise, Study 3 showed that NNSs were slower than NSs in processing collocations. Overall, the studies reported here suggest that L2 learners are capable of producing a large number of appropriate collocations but that the underlying intuitions and the fluency with collocations of even advanced learners do not seem to match those of native speakers.
Central nervous system therapy for lysosomal storage disorders
Authors: Enns Gregory M. , Huhn Stephen L.
Published: March 2008

✓ Most lysosomal storage disorders are characterized by progressive central nervous system impairment, with or without systemic involvement. Affected individuals have an array of symptoms related to brain dysfunction, the most devastating of which is neurodegeneration following a period of normal development. The blood–brain barrier has represented a significant impediment to developing therapeutic approaches to treat brain disease, but novel approaches—including enzyme replacement, small-molecule, gene, and cell-based therapies—have given children afflicted by these conditions and those who care for them hope for the future.
Stroke repair with cell transplantation: neuronal cells, neuroprogenitor cells, and stem cells
Authors: Kondziolka Douglas , Wechsler Lawrence
Published: March 2008

✓ Stroke is a common cause of death and disability. The role of cellular transplantation to promote functional recovery has been explored. Preclinical studies first established the potential for cultured neuronal cells derived from a teratocarcinoma cell line to be tested for safety and efficacy in the treatment of human stroke. In animal models of stroke that caused reproducible learning and motor deficits, injection of neuronal cells resulted in a return of learning behavior retention time and motor function. In this report the authors review several current concepts for cellular repair, discuss important patient selection and surgical technique issues, and discuss plans for future experiments.
Intravascular cell replacement therapy for stroke
Authors: Guzman Raphael , Choi Raymond , Gera Atul , De Los Angeles Alejandro , Andres Robert H. , Steinberg Gary K.
Published: March 2008

✓ The use of stem cell transplantation to restore neurological function after stroke is being recognized as a potential novel therapy. Before stem cell transplantation can become widely applicable, however, questions remain about the optimal site of delivery and timing of transplantation. In particular, there seems to be increasing evidence that intravascular cell delivery after stroke is a viable alternative to intracerebral transplantation. In this review, the authors focus on the intravascular delivery of stem cells for stroke treatment with an emphasis on timing, transendothelial migration and possible mechanisms leading to neuroprotection, angiogenesis, immunomodulation, and neural plasticity. They also review current concepts of in vivo imaging and tracking of stem cells after stroke.
New strategy for the analysis of phenotypic marker antigens in brain tumor–derived neurospheres in mice and humans
Authors: Bleau Anne-Marie , Howard Brian M. , Taylor Lauren A. , Gursel Demirkan , Greenfield Jeffrey P. , Lim Tung H. Y. , Holland Eric C. , Boockvar John A.
Published: March 2008

Object

Brain tumor stem cells (TSCs) hypothetically drive the malignant phenotype of glioblastoma multiforme (GBM), and evidence suggests that a better understanding of these TSCs will have profound implications for treating gliomas. When grown in vitro, putative TSCs grow as a solid sphere, making their subsequent characterization, particularly the cells within the center of the sphere, difficult. Therefore, the purpose of this study was to develop a new method to better understand the proteomic profile of the entire population of cells within a sphere.

Methods

Tumor specimens from patients with confirmed GBM and glioma models in mice were mechanically and enzymatically dissociated and grown in traditional stem cell medium to generate neurospheres. The neurospheres were then embedded in freezing medium, cryosectioned, and analyzed with immunofluorescence.

Results

By sectioning neurospheres as thinly as 5 μm, the authors overcame many of the problems associated with immunolabeling whole neurospheres, such as antibody penetration into the core of the sphere and intense background fluorescence that obscures the specificity of immunoreactivity. Moreover, the small quantity of material required and the speed with which this cryosectioning and immunolabeling technique can be performed make it an attractive tool for the rapid assessment of TSC character.

Conclusions

This study is the first to show that cryosectioning of neurospheres derived from glioma models in mice and GBM in humans is a feasible method of better defining the stem cell profile of a glioma.
Generation of embryonic stem cells: limitations of and alternatives to inner cell mass harvest
Authors: Das Sunit , Bonaguidi Michael , Muro Kenji , Kessler John A.
Published: March 2008

✓ Embryonic stem (ES) cells are pluripotent cells derived from the inner cell mass of the early mammalian embryo. Because of their plasticity and potentially unlimited capacity for self-renewal, ES cells have generated tremendous interest both as models for developmental biology and as possible tools for regenerative medicine. This excitement has been attenuated, however, by scientific, political, and ethical considerations. In this article the authors describe somatic cell nuclear transfer and transcription-induced pluripotency, 2 techniques that have been used in attempts to circumvent the need to derive ES cells by the harvest of embryonic tissue.
Cell therapy in Huntington disease
Authors: Clelland Claire D. , Barker Roger A. , Watts Colin
Published: March 2008

✓ Huntington disease (HD), caused by polyglutamate expansions in the huntingtin protein, is a progressive neurodegenerative disease resulting in cognitive and motor impairments and death. Neuronal dysfunction and degeneration contribute to progressive physiological, motor, cognitive, and emotional disturbances characteristic of HD. A major impetus for research into the treatment of HD has centered on cell therapy strategies to protect vulnerable neuronal cell populations or to replace dysfunctional or dying cells. The work underlying 3 approaches to HD cell therapy includes the potential for self-repair through the manipulation of endogenous stem cells and/or neurogenesis, the use of fetal or stem cell transplantation as a cell replacement strategy, and the administration of neurotrophic factors to protect susceptible neuronal populations. These approaches have shown some promising results in animal models of HD. Although striatal transplantation of fetal-derived cells has undergone clinical assessment since the 1990s, many cell therapy strategies have yet to be applied in the clinic environment. A more thorough understanding of the pathophysiologies underlying HD as well as the response of both endogenous and exogenous cells to the degenerating brain will inform their merit as potential therapeutic agents and enhance the framework by which the success of such strategies are determined.
Shifting the balance: cell-based therapeutics as modifiers of the amyotrophic lateral sclerosis–specific neuronal microenvironment
Authors: Riley Jonathan , Sweeney Walter , Boulis Nicholas
Published: March 2008

✓ Recent advances in the laboratory have improved the current understanding of neurobiological mechanisms underlying the initiating events and pathological progression observed in amyotrophic lateral sclerosis (ALS). Whereas initial studies have revealed the late-stage intracellular cascades contributing to neuronal dysfunction and cell death, more recently collected data have begun to elucidate the presence and importance of a “non–cell autonomous” component indicating that affected glial cell subtypes may serve distinct and required roles. Pharmacological interventions for ALS have largely been disappointing likely in part because they have failed to address either the proximate events contributing to neuronal dysfunction and death or the deleterious contributions of non-neuronal cells within the local microenvironment. Alternatively, cell-based therapeutics offer the potential of a multifaceted approach oriented toward the dual ends of protecting remaining viable neurons and attempting to restore neuronal function lost as a manifestation of disease progression. The authors review the evolving knowledge of disease initiation and progression, with specific emphasis on the role of affected glia as crucial contributors to the observed ALS phenotype. This basis is used to underscore the potential roles of cell-based therapeutics as modifiers of the ALS-specific microenvironment.
The use of LabVIEW and data acquisition unit to monitor and control a bench‐top air‐to‐water heat pump
Authors: Abu‐Mulaweh H. I. , Mueller D. W.
Published: March 2008

A bench‐top air‐to‐water heat pump was designed, developed, and constructed by a multidisciplinary capstone senior design team. This experimental apparatus is currently being used to demonstrate to undergraduate students some thermodynamics and heat transfer concepts and principles. A PC‐based control system which consists of LabVIEW and data acquisition (DAQ) unit is employed to monitor and control this experimental laboratory apparatus. This paper provides details about the integration of the electrical/electronic component and the control system. © 2008 Wiley Periodicals, Inc. Comput Appl Eng Educ 16: 83–91, 2008; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20122
A real‐time computer‐controlled simulator: For control systems
Authors: Altas I. H. , Aydar H.
Published: March 2008

A real‐time simulator to accompany automatic control system courses is introduced. The design and realization methods and processes are discussed. The simulator is basically a computer‐controlled system that implements the developed user friendly virtual interface software to control the speed of a small size DC motor. The virtual interface includes digital implementation models of classical proportional, integral, derivative, and all combinations of them as well as a fuzzy logic controller. The user is able to select and adjust the parameters of any desired controller that is defined and represented virtually. © 2008 Wiley Periodicals, Inc. Comput Appl Eng Educ 16: 115–126, 2008; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20130