bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of Positron Emission Tomography in Pharmacokinetic Studies to Investigate Therapeutic Advantage in a Phase I Study of 120-Hour Intravenous Infusion XR5000
Authors: Propper D.J. , de Bono J. , Saleem A. , Ellard S. , Flanagan E. , Paul J. , Ganesan T.S. , Talbot D.C. , Aboagye E.O. , Price P. , Harris A.L. , Twelves C.
Published: January 2003

Purpose: XR5000 (N-[2-(dimethylamino)ethyl]acridine-4-carboxamide) is a topoisomerase I and II inhibitor. Because the cytotoxicity of XR5000 increases markedly with prolonged exposure, we performed a phase I study of weekly XR5000 by 120-hour continuous infusion over 3 weeks.

Patients and Methods: Twenty-four patients with advanced solid cancer were treated at seven dose levels (700 to 4,060 mg/m2/120 hrs) for a total of 67 cycles. Three patients underwent positron emission tomography (PET) studies at the maximum-tolerated dose (MTD) to evaluate normal tissue and tumor carbon-11 radiolabeled XR5000 ([11C]XR5000) pharmacokinetics.

Results: The dose-limiting toxicity was National Cancer Institute Common Toxicity Criteria (version 1) grade 4 chest and abdominal pain affecting the single patient receiving 4,060 mg/m2/120 hours, and the MTD was 3,010 mg/m2/120 hours. Other grade 3–4 toxicities, affecting single patients at the MTD, were myelosuppression (grade 4), raised bilirubin, vomiting, and somnolence (all grade 3). There was one partial response (adenocarcinoma of unknown primary); the remainder had progressive disease. [11C]XR5000 distributed well into the three tumors studied by PET. Tumor uptake (maximum concentration or area under the concentration versus time curve [AUC]) was less than in normal tissue in which the tumors were located. Tumor exposure (AUC; mean ± SD in m2/mL/sec) increased when [11C]XR5000 was administered during an infusion of XR5000 (0.403 ± 0.1), compared with [11C]XR5000 given alone (0.292 ± 0.1; P < .05), indicating that tumor drug exposure was not saturated.

Conclusion: The recommended dose for XR5000 in phase II studies is 3,010 mg/m2/120 hours. PET studies with 11C-labeled drug were feasible and demonstrated in vivo distribution into tumors. Saturation of tumor exposure was not reached at the MTD.
Phase II Trial of Procarbazine, Lomustine, and Vincristine as Initial Therapy for Patients With Low-Grade Oligodendroglioma or Oligoastrocytoma: Efficacy and Associations With Chromosomal Abnormalities
Authors: Buckner Jan C. , Gesme Dean , O’Fallon Judith R. , Hammack Julie E. , Stafford Scott , Brown Paul D. , Hawkins Roland , Scheithauer Bernd W. , Erickson Bradley J. , Levitt Ralph , Shaw Edward G. , Jenkins Robert
Published: January 2003

Purpose: The purpose of this article is to determine the response rate and toxicity of PCV administered before radiation therapy in patients with newly diagnosed LGO/LGOA and to explore correlations between response with 1p/19q deletions and aberrant p53 expression.

Background: Despite prolonged survival of patients with low-grade oligodendroglioma (LGO) and oligoastrocytoma (LGOA), the majority will succumb to progressive disease. Because procarbazine, lomustine (CCNU), and vincristine (PCV) is active in patients with recurrent LGO/LGOA, we hypothesized that it would be beneficial as primary therapy.

Methods: Adult patients with residual tumor on magnetic resonance imaging scan following biopsy or subtotal resection of LGO/LGOA received up to six cycles of PCV. Radiation therapy (59.4 or 54.0 Gy) began within 10 weeks of completing chemotherapy or immediately if there was evidence of tumor progression on PCV. Tumor tissue was analyzed by fluorescent in situ hybridization for 1p and 19q deletion and by immunohistochemistry for p53 expression.

Results: Eight of 28 (29%) and 13 of 25 (52%) eligible patients demonstrated tumor regression as assessed by the treating physician and a blinded central neuroradiology reviewer, respectively. Myelosuppression was the predominant toxicity. Loss of 1p and 19q were associated with LGO but not LGOA (P = .009), were inversely associated with p53 detection, and were not associated with response to PCV (possibly because of the small sample size).

Conclusion: PCV produces tumor regressions in a meaningful proportion of patients with LGO/LGOA. Toxicity, especially myelosuppression, is significant. Loss of 1p and 19q seems limited to patients with pure LGO and is inversely related to p53 alterations.
Changes in food consumption expenditure in Malaysia
Authors: Ishida Akira , Law Siong‐Hook , Aita Yoshihisa
Published: January 2003

In rapidly developing Asian countries, food consumption has drastically expanded and diversified. Trends in Malaysian food consumption are typical of those of developing countries. The overriding objective of this article, therefore, was to explore the structural changes in food consumption expenditure in West Malaysia after the early 1970s when its food consumption diversified under rapid economic growth and urbanization. We have estimated Engel's expenditure elasticities for food items using aggregated cross‐sectional data from the Household Expenditure Survey. Our estimated results clearly indicate that while the expenditure elasticities of away‐from‐home food, and the elasticities of at‐home expenditures for meat, fruits and vegetables, milk and dairy products are relatively high, those of rice and sugar are low. This suggests that the food expenditure structure in West Malaysia has diversified, adding meat, fruits and vegetables, milk and dairy products to the most dominant food item, rice. Moreover, it is likely that the share of food away from home will increase with income enhancement and urbanization due mainly to economic growth. [EconLit citations: Q11 (Aggregate Demand and Supply)]. © 2003 Wiley Periodicals, Inc. Agribusiness 19: 61–76, 2003.
Asymmetric price transmission due to market power in the case of supply shocks
Authors: Bunte Frank , Peerlings Jack
Published: January 2003

In this article the market power argument for explaining asymmetric price transmission due to market power in case of supply shocks is examined. Moreover, the potential welfare effects are examined. The analysis is performed using an extension of the Azzam and Schroeter (1995) model comprising both oligopsony and oligopoly instead of just oligopsony. The model is given empirical content using data on the Dutch cucumber chain and assuming Cournot competition among retailers who have market power on either the consumer/retail or growers/retail market or both. The results show that in case of a cucumber supply shock and market power, consumer prices change more than growers' prices. Moreover, total welfare effects of market power are small but potentially large income distribution effects exist. [EconLit citations: L130, Q130.] © 2003 Wiley Periodicals, Inc. Agribusiness 19: 19–28, 2003.
Consumer demand for and attitudes toward alternative beef labeling strategies in France, Germany, and the UK
Authors: Roosen Jutta , Lusk Jayson L. , Fox John A.
Published: January 2003

Food safety scares have led to loss of consumer confidence in the quality and safety of beef products in Europe. To counteract such concerns, firms and regulators can use brands or labels to signal quality. Using data from mail surveys in France, Germany, and the United Kingdom, we analyze consumer preferences for alternative beef labeling strategies: brands, origin labels, and mandatory labeling of beef from cattle fed genetically modified feed. The analysis suggests that consumers place more importance on labels of origin as opposed to private brands. More than 90% of surveyed consumers wanted a mandatory labeling program for beef produced from cattle fed genetically modified crops. [EconLit citations: D120, L660.] © 2003 Wiley Periodicals, Inc. Agribusiness 19: 77–90, 2003.
Effect of liberalized U.S.–Mexico rice trade: A spatial, multiproduct equilibrium analysis
Authors: Fuller Stephen , Fellin Luis , Salin Victoria
Published: January 2003

A spatial, multiproduct equilibrium model featuring United States–Mexico long‐grain rice trade is developed to determine the effect of removing Mexico's rice tariffs in 2003 on U.S. rough and milled rice exports to that country. Analysis considers rice milling costs and yields in the United States and Mexico, transportation costs associated with U.S. rice exports to Mexico, mill by‐product prices in Mexico and the United States and the changing tariff levels. Results show Mexico's graduated decline in rice tariffs over the 1997 to 2003 period to increase U.S. rice exports to Mexico about 1% per year or a total of 7% over the 6‐year period. United States' long‐grain rice price and production is modestly affected by the increased exports, while the impact on Mexico's rice production and price is comparatively large. Further, results show the historic incentive to export rough rice to Mexico will be replaced by an incentive to export milled rice, thus opportunities for the U.S. rice milling industry to form alliances with Mexican packers and increase direct relationships with large retailers in Mexico. [EconLit citations:C61, Q17, and R40.] © 2003 Wiley Periodicals, Inc. Agribusiness 19: 1–17, 2003.
Consumer beliefs and attitude towards genetically modified food: Basis for segmentation and implications for communication
Authors: Verdurme Annelies , Viaene Jacques
Published: January 2003

Results from a consumer survey comprising 400 face‐to‐face interviews with Flemish consumers (Belgium), which was conducted in the summer of 2000, reveal four consumer segments based on beliefs and attitude towards genetically modified (GM) food, namely: the Halfhearted, the Green Opponents, the Balancers, and the Enthusiasts. While 23.5% of the respondents have positive attitudes (the Enthusiasts) towards GM food, 15.5% are reluctant (the Green Opponents). The other 61.0% of the respondents have rather neutral (the Balancers) to slightly negative (the Halfhearted) attitudes towards GM food. Each of these identified segments can be further profiled in terms of socio‐economic and demographic characteristics, knowledge, general attitudes including trust, information needs, consulted and trusted information sources and channels, and purchase intentions. These insights will provide the necessary input for the development of an effective segmented communication strategy. [EconLit citations: Q130, Q160, Q180.] © 2003 Wiley Periodicals, Inc. Agribusiness 19: 91–113, 2003.
Localized hypoplasia of the primary canine in bonobos, orangutans, and gibbons
Authors: Skinner Mark F. , Newell Elizabeth A.
Published: January 2003

This paper extends observations by Lukacs ([1999] Am. J. Phys. Anthropol. 110:351–363; [2001] Am. J. Phys. Anthropol. 116:199–208) of localized hypoplasia of the primary canine (LHPC) among large apes to gibbons, bonobos, and orangutans. LHPC is a roughly circular area of deficient enamel on the labial surface of primary canine teeth which, on current evidence from humans, forms several months after birth due to malnutrition‐induced craniofacial osteopenia, leading to crypt fenestration that exposes the dental follicle and more deep‐sited ameloblasts to minor physical traumata during normal motor infant development. Our goal was to determine the prevalence of LHPC among a variety of apes which differ in body mass and socioecology, with a view to elucidating the etiology of the defect. We examined juvenile dentitions from 122 animals from three taxa: 8 Hylobates lar, 75 Pongo pygmaeus from Borneo and Sumatra, and 39 Pan paniscus from central Africa. Reported variables include taxon, sex, arcade, side, and tooth size. Presence/absence and ordinal severity of defect expression were recorded by description, microphotography, and scanning electron microscopy. Molds were taken in high‐resolution dental impression materials and cast in epoxy resin.

There are clear taxonomic, but no sex, differences. Prevalence ranged from 0.0% in gibbons to 61.5% in bonobos and 85.3% in orangutans. The result for orangutans is similar to that reported by Lukacs ([1999] Am. J. Phys. Anthropol. 110:351–363), while bonobos are much more affected than were the common chimpanzees (22%) described by Lukacs ([1999] Am. J. Phys. Anthropol. 110:351–363). There are no significant antimeric differences, but the lower canine is much more affected than the upper by LHPC. We show that larger teeth are more affected by LHPC and have more severe defects. Also, we encountered several instances of patent or healing canine crypt fenestrations, occasionally in direct association with LHPC. Location of the defect indicates that LHPC may occur perinatally but more usually several months postnatally. Histological examination showing the neonatal line and LHPC is required to resolve the issue of timing. We concur with Lukacs ([1999] Am. J. Phys. Anthropol. 110:351–363) that taxonomic, anatomical, and environmental variables combine to determine the occurrence and appearance of LHPC. Nevertheless, we conclude that LHPC probably reflects deficient growth of the arcades in infant apes and humans. Am J Phys Anthropol 120:61–72, 2003. © 2003 Wiley‐Liss, Inc.
Analysis of colored teeth from precolumbian tlatelolco: Postmortem transformation or intravitam processes?
Authors: Mansilla J. , Solis C. , Chávez‐Lomeli M.E. , Gama J.E.
Published: January 2003

The etiological basis of the abnormal coloration of archaeological teeth has been an unsolved question for a long time. Differences in the appearance of some archaeological teeth from Precolumbian adult and infant skeletons, detected by external optical inspection, led us to study this problem. A blue stain is visible in a few of the deciduous erupted teeth, and a brown color in various unerupted teeth in the collection, while brown spots appear on some permanent teeth. Several processes or factors that may occur during one's life, others around the time of death, and still others resulting from postmortem alterations have been reported as potential causes of abnormal tooth coloration.

A sample of 35 colored teeth and two soil layers taken from Tlatelolco were analyzed by particle‐induced X‐ ray emission (PIXE) as well as selective dissolution techniques. Concentrations of total and extractable elements in enamel and soil layers (Cg1–Cg2) were obtained. This paper describes the occurrence and implications of a substantial secondary concentration of Zinc (Zn), manganese (Mn), strontium (Sr), and iron (Fe) in the deciduous erupted and nonerupted teeth as compared to that in the adult teeth.

Our interpretation is that, in this archaeological context, the brown spots and blue stains on the teeth are due to differences in tooth enamel porosity and to a postmortem biogeochemical process. The alterations involve cumulization and diagenesis of iron, manganese, and organic matter solutions that were eluviated from the soil and are not the result of antemortem or perimortem conditions such as trauma or disease. Am J Phys Anthropol 120:73–82, 2003. © 2003 Wiley‐Liss, Inc.
Scaling relationships between craniofacial sexual dimorphism and body mass dimorphism in primates: Implications for the fossil record
Authors: Plavcan J. Michael
Published: January 2003

Craniofacial remains (the most abundant identifiable remains in the fossil record) potentially offer important information about body size dimorphism in extinct species. This study evaluates the scaling relationships between body mass dimorphism and different measures of craniofacial dimorphism, evaluating taxonomic differences in the magnitude and scaling of craniofacial dimorphism across higher taxonomic groups. Data on 40 dimensions from 129 primate species and subspecies demonstrate that few dimensions change proportionally with body mass dimorphism. Primates show general patterns of greater facial vs. neurocranial and orbital dimorphism, and greater dimorphism in lengths as opposed to breadths. Within any species, though, different craniofacial dimensions can yield very different reconstructions of size dimorphism. There are significant taxonomic differences in the relationships between size and craniofacial dimorphism among primate groups that can have a significant impact on reconstructions of body mass dimorphism. Hominoids tend to show lower degrees of facial dimorphism proportional to size dimorphism than other primates. This in turn implies that strong craniofacial dimorphism in Australopithecus africanus could imply very strong body size dimorphism, conflicting with the relatively modest size dimorphism inferred from postcrania. Different methods of estimating the magnitude of size dimorphism from craniofacial measurements yield similar results, and yield comparatively low percent prediction errors for a number of dimensions. However, confidence intervals for most estimates are so large as to render most estimates highly tentative. Am J Phys Anthropol 120:38–60, 2003. © 2003 Wiley‐Liss, Inc.
Correlation of knee‐joint cartilage morphology with muscle cross‐sectional areas vs. anthropometric variables
Authors: Hudelmaier Martin , Glaser Christian , Englmeier Karl‐Hans , Reiser Maximilian , Putz Reinhard , Eckstein Felix
Published: January 2003

We tested the hypothesis that muscle cross‐sectional areas (MCSAs) are more highly (and independently) correlated with cartilage morphology than are body height and weight, and that the physiological reduction of cartilage thickness with aging is associated with a proportional, age‐dependent decrease in MCSAs. In 59 asymptomatic individuals (23–75 years old), morphological parameters of the knee cartilages (volume, thickness, and bone–cartilage interface area), and MCSAs were determined from magnetic resonance imaging (MRI) data. Multiple regression models were used to calculate which proportion of the variability of the normal cartilage morphology can be predicted based on independent variables. MCSAs and body height and weight showed correlation coefficients of +0.66, +0.60, and +0.25, respectively, with knee‐joint cartilage volume. The correlation coefficients with cartilage thickness were +0.44, +0.35, and +0.24, respectively. Age accounted for a significant (P < 0.01) reduction in cartilage thickness, but there was no proportional change of MCSAs. Approximately 76% of the variability of the knee cartilage volume could be predicted from independent variables in a multiple regression model with MCSAs contributing significant, independent information. In conclusion, we find that MCSAs are more highly correlated with cartilage morphology than are body height and weight. The significant decrease in cartilage volume and thickness with age is not associated with a proportional decrease in MCSAs. Anat Rec Part A 270A:175–184, 2003. © 2003 Wiley‐Liss, Inc.
p75NTR in the spleen: Age‐dependent changes, effect of NGF and 4‐methylcatechol treatment, and structural changes in p75NTR‐deficient mice
Authors: Pérez‐Pérez M. , García‐Suárez O. , Esteban I. , Germanà A. , Fariñas I. , Naves F.J. , Vega J.A.
Published: January 2003

In addition to their well‐known actions within the nervous system, neurotrophins and their receptors are involved in immune system functioning, as demonstrated by their wide distribution in lymphoid tissues and their in vitro actions on immunocompetent cells. Nevertheless, the in vivo roles of neurotrophin‐receptor systems in lymphoid tissues, as well as the scope of their influence throughout development and adulthood, are yet to be clarified. In the present study, we used combined morphological and immunohistochemical techniques to investigate the presence and cellular localization of p75NTR, the pan‐neurotrophin receptor protein, in rat spleen from newborns to aging individuals, and the structural and innervation changes in the spleens of p75NTR‐deficient mice. In rats, p75NTR was expressed by splenic nerve fibers and dendritic cells in an age‐regulated fashion, with maximal expression detected at 2 weeks. Consistently, the spleens of newborn mice lacking this receptor protein showed no signs of ingrowing sympathetic fibers, along with an absence of defined white pulp areas. The present findings suggest a prolonged role of p75NTR in the physiology of the spleen; at least during the embryonic development period, the receptor may be critical for correct innervation and compartmentalization processes to occur. Anat Rec Part A 270A:117–128, 2003. © 2003 Wiley‐Liss, Inc.
Establishment of cadherin‐based intercellular junctions in the dermal papilla of the developing hair follicle
Authors: Nanba Daisuke , Nakanishi Yasuo , Hieda Yohki
Published: January 2003

During hair follicle development, mesenchymal cells aggregate to form the dermal papilla with hair‐inducing activity. However, the cellular mechanisms underlying the aggregative behavior of dermal papilla cells are less known. The present study demonstrates that cadherin‐based intercellular junctions interconnect dermal papilla cells in developing hair follicles of mice. It is shown that as mesenchymal cells aggregate to be surrounded by epithelium in developing hair follicles, cadherin‐11 comes to exhibit the dotted patterns of distribution. The appearance of the dot‐like distribution of the molecule is concomitant with the formation of intercellular junctions in the mesenchymal aggregate, which make a tightly packed population of cells with little extracellular space. At later stages of the development, although extracellular space reappears in the dermal papilla, the cells remain interconnected by well‐developed intercellular junctions, where cadherin‐11 as well as β‐catenin is localized. Taking into consideration the normal hair development in cadherin‐11 mutant mice, it might be that multiple cadherins are responsible for the establishment of intercellular junctions in the dermal papilla and serve to maintain the aggregative behavior of the cells. Anat Rec Part A 270A:97–102, 2003. © 2003 Wiley‐Liss, Inc.
Ultrastructural morphology of adrenal chromaffin cells indicative of a process of piecemeal degranulation
Authors: Crivellato Enrico , Nico Beatrice , Perissin Laura , Ribatti Domenico
Published: January 2003

Chromaffin cells of the mouse adrenal medulla were found by transmission electron microscopy (TEM) to exhibit ultrastructural changes suggestive of piecemeal degranulation (PMD), a unique model of cell secretion characterized by the slow release of granule materials without granules opening to the cell exterior. The expression of PMD was recognized in both adrenaline‐ and noradrenaline‐containing cells. Ultrastructural changes included specific granule and cytoplasmic morphologies. In adrenaline‐releasing cells the granule content was loosely packed or condensed, and surrounded by a clear halo. In noradrenaline‐storing cells, the granule material appeared asymmetically arranged and exhibited characteristic “semilunar” electron‐dense domains within the granule chambers. Notably, altered granules did not fuse with each other or with the plasma membrane, and were intermingled with normal, resting granules. Large, empty cytoplasmic containers or vacuoles filled with partially dissolved matrices were frequently observed. In addition, both adrenaline‐ and noradrenaline‐storing cells presented a rich supply of membrane‐bound, smooth vesicles (50–200 nm diameter) that were either free in the cytoplasm or attached to granules. The finding of ultrastructural features characteristic of PMD in adrenal chromaffin cells suggests that such a secretory model may be an alternative secretory pathway to regulated exocytosis. Moreover, these results support the hypothesis that PMD may be a general degranulation pattern in cells involved in paracrine‐endocrine secretion. Anat Rec Part A 270A:103–108, 2003. © 2003 Wiley‐Liss, Inc.
Effects of experimental diabetes on the structure and ultrastructure of the coagulating gland of C57BL/6J and NOD mice
Authors: Carvalho C.A.F. , Camargo A.M. , Cagnon V.H.A. , Padovani C.R.
Published: January 2003

Diabetes mellitus can lead to reproductive disorders that in turn result in weakened fertility brought about by morphofunctional changes in the testes and accessory sex glands. However, doubts persist concerning the basic biology of the secretory epithelial cells and the stroma of the coagulating gland of diabetic mice. Thus, the objective of the present study was to analyze the histological and ultrastructural changes associated with stereology of the coagulating gland of mice with alloxan‐induced diabetes, and of spontaneously diabetic mice. Sixteen mice of the C57BL/6J strain, and eight non‐obese diabetic (NOD) mice were used. The animals were divided into three groups: 1) control (C), 2) alloxan diabetic (AD), and 3) NOD. Thirty days after the detection of diabetic status in group 2, all of the animals were killed and then perfused with Karnovsky's solution through the left cardiac ventricle. The coagulating gland was then removed and processed for morphometric study by light microscopy and electron microscopy. The results showed thickening of the stroma, atrophy of secretory epithelial cells, and disorganization of the organelles involved in the secretory process in both NOD and alloxan‐induced mice. Thus, it may be concluded that the coagulating gland suffered drastic morphological changes, and consequently impaired glandular function, in the presence of diabetes mellitus type I in both NOD and AD mice. Anat Rec Part A 270A:129–136, 2003. © 2003 Wiley‐Liss, Inc.
Specific biological functions of vacuolar‐type H+‐ATPase and lysosomal cysteine proteinase, cathepsin K, in osteoclasts
Authors: Sahara Takako , Itoh Kanami , Debari Kazuhiro , Sasaki Takahisa
Published: January 2003

We report the effects of specific and potent inhibitors of vacular‐type H+‐ATPase and lysosomal cysteine proteinases, cathepsins, on the ultrastructure, expression of these enzymes, and resorptive functions of cultured osteoclasts. Osteoclasts were formed by co‐culture of marrow cells and calvarial primary osteoblasts of ddY mice. Formed osteoclasts were cultured on dentine slices for 6–48 hr with either an H+‐ATPase inhibitor, bafilomycin A1, or a cysteine proteinase inhibitor, E‐64. In control cultures with no additive, osteoclasts were structurally characterized by the development of ruffled borders and clear zones, and formed many resorption lacunae on dentine slices. Both H+‐ATPase and cathepsin K were strongly expressed in the ruffled borders of these osteoclasts. In bafilomycin A1‐treated cultures, osteoclasts lacked ruffled borders, and resorption lacuna formation was markedly diminished. This effect of bafilomycin A1 on osteoclast structure was reversible by removal of the compound. Bafilomycin A1 treatment altered the subcellular localization and decreased the expression of H+‐ATPase molecules. H+‐ATPase expression was observed throughout the cytoplasm, but not along the plasma membranes facing dentine slices. On the other hand, E‐64 treatment did not affect the ultrastructure of osteoclasts and the expression of enzyme molecules. Although E‐64 showed no effect on demineralization of dentine slices, it dose‐dependently reduced resorption lacuna formation. Our results suggest that 1) bafilomycin A1 dose‐dependently inhibits resorption lacuna formation via inhibition of ruffled border formation, 2) H+‐ATPase expression is closely associated with the cytoskeleton of osteoclasts, and 3) E‐64 treatment decreases the depth of resorption lacunae, by inhibition of secreted cathepsin K activity, but does not impair ruffled border formation and the associated expression of H+‐ATPase and cathepsin K in osteoclasts. Anat Rec Part A 270A:152–161, 2003. © 2003 Wiley‐Liss, Inc.
Effect of the meniscus at the solid/liquid interface on the SAR distribution in Petri dishes and flasks
Authors: Schuderer Jürgen , Kuster Niels
Published: January 2003

Several authors have reported that the meniscus as occurring at the walls of Petri dishes and flasks (solid–liquid interface) can significantly affect the SAR distribution in the entire dish and flask, while others have ignored this effect. In this study, this effect has been comprehensively analyzed by numerical means supported by theoretical considerations. The focus is on E polarization, which results in the most homogeneous exposure for monolayer cell cultures and therefore is the most often applied polarization in exposure setups for risk assessment studies. This includes setups based on TEM cells, waveguides, radial transmission lines (RTL), and HF chambers. The conclusion of this study is that the meniscus and its size have a significant effect on the strength and homogeneity of the induced SAR distribution. Hence, the meniscus needs to be accounted for in the determination of the averaged SAR as well as in the uncertainty assessment. It has also been demonstrated that a voxel size of less than 0.2 mm is needed to predict the SAR values for a monolayer of cells accurately. Bioelectromagnetics 24:103–108, 2003. © 2003 Wiley‐Liss, Inc.
A 60 Hz magnetic field does not affect the incidence of squamous cell carcinomas in SENCAR mice
Authors: McLean J.R. , Thansandote A. , McNamee J.P. , Tryphonas L. , Lecuyer D. , Gajda G.
Published: January 2003

Two groups of SENCAR mice were treated with a single dose of carcinogen and then, for 23 weeks, with a chemical tumor promoter to induce skin tumors. During this period, one group was coexposed to a 2 mT power frequency (60 Hz) magnetic field, while the other was exposed to sham conditions. Application of the tumor promoter ceased after 23 weeks, but the exposure to sham conditions or magnetic fields continued for an additional 29 weeks. No difference was found between the two groups of mice in terms of the incidence of total tumors (P = .297) or squamous cell carcinomas (SSC) (P = .501). In summary, there was no evidence to support the hypotheses that 60 Hz magnetic fields (MF) can influence the development of either papillomas or SSC under our defined experimental conditions. The overall results add to previous animal studies that find no association between exposure to 60 Hz MF and the incidence of benign or malignant tumors. Bioelectromagnetics 24:75–81, 2003. © 2003 Wiley‐Liss, Inc.
ELF magnetic fields induce internalization of gap junction protein connexin 43 in Chinese hamster lung cells
Authors: Zeng Q.L. , Chiang H. , Hu G.L. , Mao G.G. , Fu Y.T. , Lu D.Q.
Published: January 2003

We have previously demonstrated that exposure of Chinese hamster lung (CHL) cells to 50 Hz magnetic fields (MFs) and/or 12‐O‐tetradecanoylphorbol‐3‐acetate (TPA)‐inhibited gap junctional intercellular communication (GJIC). To explore and compare the mechanisms of GJIC inhibition induced by extremely low frequency (ELF) MF and TPA, the number and localization of connexin 43 (Cx43) were studied. The localization of Cx43 was determined with indirect immunofluorescence histochemical analysis and detected by confocal microscopy after exposing CHL cells to 50 Hz sinusoidal magnetic field at 0.8 mT for 24 h without or with TPA (5 ng/ml) for the last 1 h. The Cx43 levels in nuclei and in cytoplasm were examined by Western blotting analysis. The results showed that the cells exposed to MF and/or TPA displayed individual plaques at regions of intercellular contact, which were fewer than the normal cells in number, while the number of Cx43 in cytoplasm increased and congregated near the nuclei. Western blot analysis further demonstrated the quantity of changes in location of Cx43. These results suggest that reduction of Cx43 at regions of intercellular contact may be one of the mechanisms of GJIC inhibition induced by ELF MF. Bioelectromagnetics 24:134–138, 2003. © 2003 Wiley‐Liss, Inc.
The effect of strong static magnetic field on lymphocytes
Authors: Aldinucci Carlo , Garcia Julian Blanco , Palmi Mitri , Sgaragli Gianpietro , Benocci Alberto , Meini Antonella , Pessina Federica , Rossi Claudio , Bonechi Claudia , Pessina Gian Paolo
Published: January 2003

We investigated whether static electromagnetic fields (EMFs) at a flux density of 4.75 T, generated by an NMR apparatus (NMRF), could promote movements of Ca2+, cell proliferation, and the eventual production of proinflammatory cytokines in human peripheral blood mononuclear cells (PBMC) as well as in Jurkat cells, after exposure to the field for 1 h. The same study was also performed after activation of cells with 5 mg/ml phytohaemagglutinin (PHA). Our results clearly demonstrate that static NMRF exposure has neither proliferative, nor activating, nor proinflammatory effects on both normal and PHA activated PBMC. Moreover, the concentration of interleukin‐1β, interleukin‐2, interleukin‐6, interferon, and tumour necrosis factor α (TNFα) remained unvaried in exposed cells. Exposure of Jurkat cells statistically decreased the proliferation and the proliferation indexes, which 24 and 48 h after exposure were 0.7 ± 0.29 and 0.87 ± 0.12, respectively. Moreover, in Jurkat cells the [Ca2+]i was higher than in PBMC and was reduced significantly to about one half after exposure. This is consistent with the decrease of proliferation and with the low levels of IL‐2 measured. On the whole, our data suggest that NMRF exposure failed to affect the physiologic behaviour of normal lymphomonocytes. Instead in Jurkat cells, by changing the properties of cell membranes, NMRF can influence Ca2+ transport processes, and hence Ca2+ homeostasis with improvement of proliferation. Bioelectromagnetics 24:109–117, 2003. © 2003 Wiley‐Liss, Inc.
Circularly polarised MF (500 μT 50 Hz) does not acutely suppress melatonin secretion from cultured Wistar rat pineal glands
Authors: Tripp H.M. , Warman G.R. , Arendt J.
Published: January 2003

Magnetic fields (MF, 50 Hz) have been proposed to affect melatonin production in mammals; however, there is very little data about the mechanism by which this possible interaction may occur. Here we describe results from the first study in which circularly polarised 50 Hz MF have been administered to isolated pineals in highly controlled conditions. Melatonin release from isolated Wistar rat pineal glands, dissected 2 h after light onset ZT 2, was measured in a flow through culture system, during and after exposure to a 4 h MF similar in nature and magnitude to that produced in extremely close proximity to a high voltage power line (500 μT 50 Hz circularly polarised). Melatonin release from isolated pineals was comparable to that observed in previous studies, plateauing to ∼100 pg/ml/30 min. No significant alterations in pineal melatonin release were caused by exposure to the MF when compared to sham exposure (< 1 μT). These results suggest that if the circadian system is acutely responsive to MF exposure of this nature, an intact circadian axis may be necessary in order to observe an effect on the production on melatonin from the pineal gland. Bioelectromagnetics 24:118–124, 2003. © 2003 Wiley‐Liss, Inc.
ELF fields and photooxidation yielding lethal effects on cancer cells
Authors: Traitcheva Nelly , Angelova Plamena , Radeva Maria , Berg Hermann
Published: January 2003

The lethal effect on human cancer cells was studied under three types of treatment: A) an ELF pulsed sinusoidal of 50 Hz electromagnetic field (PEMF) with amplitudes between 10 and 55 mT; B) the field and a cytostatic agent (actinomycin‐C); and C) the field, the cytostatic agent, which has a photodynamic effect, and exposure to a halogen lamp. The results show a decreasing vitality of human K‐562 and U‐937 cancer cells in suspension with each additional treatment. Combination with other parameters as hyperthermia and/or hyperacidity could yield high killing rates by this noninvasive method. Bioelectromagnetics 24:148–150, 2003. © 2003 Wiley‐Liss, Inc.
Stimulation and microswitch‐based programs for enhancing indices of happiness: a maintenance assessment
Authors: Lancioni Giulio E. , O'Reilly Mark F. , Singh Nirbhay N. , Oliva Doretta , Campodonico Francesca , Groeneweg Jop
Published: January 2003

This study assessed whether stimulation and microswitch‐based programs maintained their positive impact on indices of happiness over time. Three people with multiple disabilities, who had participated in a study comparing these programs, continued to be exposed to them over a maintenance period of 5 or 6 months. Maintenance data showed that the frequencies of indices of happiness increased or remained unchanged for two participants and declined for the third. The frequencies of microswitch activations were higher for two of the participants and largely unchanged for the other. Procedural aspects of the study, implications of the findings, and relevant issues for new research are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
The effects of dropping in‐situation safety behaviors in the treatment of social phobia
Authors: Garcia‐Palacios A. , Botella C.
Published: January 2003

Over the past years, important advances in the cognitive–behavioral treatment of social phobia have taken place. There is wide evidence that demonstrates exposure is an effective treatment for social phobia. However, some research has noticed that exposure has limitations in treating this disorder. In clinical practice we find patients who do not achieve marked reductions in anxiety using this technique. One of the mechanisms that can be involved is the use of in‐situation safety behaviors, which patients use to prevent the feared consequences in social situations. The aim of this study is to present a single case study where we compare the improvement achieved using exposure alone versus exposure dropping in‐situation safety behaviors. The social phobic patient improved significantly when exposure was combined with the drop of in‐situation safety behaviors. Copyright © 2003 John Wiley & Sons, Ltd.
Classroom applications of the disequilibrium model of reinforcement
Authors: Johnson Jesse W. , Munk Dennis D. , Van Laarhoven Toni , Repp Alan C. , Dahlquist Carol M.
Published: January 2003

The present study investigated applications of the disequilibrium model of reinforcement in typical classroom contexts with students perceived by their teachers as being difficult to motivate. The disequilibrium model states that reinforcing effects are produced when access to any response (task) is constrained so that an individual cannot meet an (unconstrained) baseline level for that response (task). The implication of the model is that low‐probability (low‐preference) responses can be constrained and used as reinforcers, a seeming contradiction to the common practice of using a high‐probability response to reinforce increases in a low‐probability response.

The present study investigated the effects of disequilibrium schedules of reinforcement with six students with several disabilities in classroom contexts. The specific research questions were (i) whether disequilibrium schedules would produce reinforcing effects if both the instrumental and contingent tasks were of moderate to low preference for the student; (ii) how effects of disequilibrium schedules would compare with those of a teacher‐generated contingency; and (iii) what effects disequilibrium schedules would have with students who engage in non‐task responding during the baseline period.

Results suggest that disequilibrium schedules are effective when used with moderate to low‐preference tasks. Results of the comparison with teacher‐generated contingencies were mixed. Results do suggest that the presence of higher levels of non‐task responding during the baseline period may affect subsequent effectiveness of disequilibrium schedules calculated from the baseline. Copyright © 2003 John Wiley & Sons, Ltd.
The treatment of dangerous behavior
Authors: Foxx Richard M.
Published: January 2003

Individuals who display dangerous behavior towards others have historically been under‐treated and under‐researched. This paper discusses three published case studies wherein adult males were effectively treated for severe aggression towards others, the environment, and, in two cases, self‐injury. All were diagnosed as having mental retardation and two also had a psychiatric diagnosis. All had experienced years of failed attempts to control their aggression through large pharmacological interventions and restricting their freedom of movement via restrictive environments. The use of comprehensive multifaceted behavioral programs involving punishment resulted in dramatic and long lasting reductions in aggression, the elimination or great reduction of drug use, and major lifestyle improvements. The conceptual, clinical, political, legal, philosophical, and ethical considerations that arose during the development and implementation of the programs are discussed as well as scientific issues related to achieving long term maintenance. An early published case study (Martin & Foxx, 1973) is discussed first because it illustrates how an informal functional analysis was used to design a very simple and effective non‐punishment treatment program for a woman who displayed dangerous aggression. Copyright © 2003 John Wiley & Sons, Ltd.
Functional analysis and treatment of bizarre vocalizations exhibited by an adult with schizophrenia: a replication and extension
Authors: Wilder David A. , White Holly , Yu Michael L.
Published: January 2003

A functional analysis suggested that the bizarre vocalizations exhibited by a woman with a diagnosis of schizophrenia were maintained by attention. A treatment consisting of awareness training, competing response training, differential reinforcement of the competing response, and attention extinction was effective in reducing bizarre vocalizations. The use of self‐management based treatment components with this population and target behavior is discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Brief mother–infant treatment: Psychoanalytically informed video feedback
Authors: Beebe Beatrice
Published: January 2003

Specific patterns of interactive regulation documented by microanalytic methods of infant research can be applied to clinical interventions with mothers and infants. A brief treatment model is described that includes face‐to‐face split‐screen videotaping (one camera on each partner) and therapeutic observation of the videotape with the parent. The intervention uses “video feedback” informed by a psychoanalytic approach, including positive reinforcement, modeling, and information giving, as well as interpretation, while watching the videotape. Specific interactions in the areas of attention, arousal, affect, and timing regulation are evaluated. The psychoanalytic intervention links the “story” of the presenting complaints, the “story” seen in the videotape, and the “story” of the parent's own upbringing. An attempt is made to identify specific representations of the baby that may interfere with the parents's ability to observe and process the nonverbal interaction. The mother's powerful experience of watching herself and her baby interact, and our joint attempts to translate the action‐sequences into words, facilitates the mother's ability to “see” and to “remember,” stimulating a rapid integration of the mother's procedural and declarative modes of information‐processing. One treatment case, involving six contacts, is presented to illustrate the approach. By applying the specificity of interactive regulation identified by microanalysis of videotape into the psychodynamic treatment of mother–infant pairs, basic research can be translated into clinical practice. ©2003 Michigan Association for Infant Mental Health.
Putting the pieces together: Maternal depression, maternal behavior, and toddler helplessness
Authors: Kelley Sue A. , Jennings Kay Donahue
Published: January 2003

This study assessed relations between maternal depression, maternal behavior, and helplessness in toddlers. Helplessness was assessed behaviorally in 25‐ and 32‐month‐old toddlers while the toddlers were engaged with an impossible task. Maternal behavior (warmth, negativity, control, intrusiveness) was assessed during a mother–child teaching task when toddlers were 18 and 25 months of age. Mothers who reported more depressive symptoms on the BDI had 32‐month‐old toddlers who displayed more affect‐related helplessness. No direct relations were found between maternal diagnosis of depression and helplessness in toddlers. Few differences emerged in the behavior of depressed and nondepressed mothers while interacting with their toddlers, and few relations were found between maternal behavior alone and toddlers' helplessness. However, results suggest that maternal behavior moderates the relation between maternal depression (diagnosis, recency, and symptoms) and helplessness. ©2003 Michigan Association for Infant Mental Health.
Remote forcing of East African rainfall and relationships with fluctuations in levels of Lake Victoria
Authors: Mistry Vinay V. , Conway Declan
Published: January 2003

This study investigates the climatological variables responsible for fluctuations in Lake Victoria levels, in particular the causal mechanism responsible for a major anomaly that occurred in 1961. A Lake Victoria rainfall series (LVRS) correlates significantly (5%) with Lake Victoria levels and is utilized for subsequent analysis of rainfall variability. Relationships between annual and seasonal (March–May and October–December (OND)) LVRS and a number of tropical and extra‐tropical series were analyzed. The results illustrate the dominance of the El Niño–Southern Oscillation phenomenon in modulating LVRS. The greatest correlation is found between LVRSOND and the Southern Oscillation index (r = −0.39, significant at the 1% level), although the relationship is non‐linear over the course of the century.

Velocity potential χ is employed as the principal diagnostic variable. Seasonal composite maps and empirical orthogonal function (EOF) analysis of Indian Ocean region χ‐fields are utilized to test the hypothesis that an Indian Ocean Walker cell is responsible for the anomalous 1961 rainfall episode. Subsequent analysis leads to the rejection of this hypothesis. EOF analysis of OND 200 hPa χ‐fields reveals a number of modes of tropical variability. EOF analysis of the Indian Ocean basin illustrates the emergence of a meridional circulation directed over the Indian Ocean (EOF5). This time series correlates significantly with LVRSOND (r = −0.40, 1% level), although the spatial pattern only explains a small proportion (2.35%) of the total variance.

χ analysis for OND over the broader tropical region reveals significant relationships (5%) between OND EOF3* and July–September Sahel rainfall for the preceding season and subsequent year. This relationship may assist future long‐lead seasonal forecast schemes for the Sahel region. Copyright © 2003 Royal Meteorological Society.