bluuebunny/crossref_metadata_2025 huggingface dataset:
Modulating Neural Networks With Transcranial Magnetic Stimulation Applied Over the Dorsal Premotor and Primary Motor Cortices
Authors: Chouinard Philippe A. , Van Der Werf Ysbrand D. , Leonard Gabriel , Paus Tomás
Published: May 2006

Our study uses the combined transcranial magnetic stimulation/positron emission tomography (TMS/PET) method for elucidating neural connectivity of the human motor system. We first altered motor excitability by applying low-frequency repetitive TMS over two cortical motor regions in separate experiments: the dorsal premotor and primary motor cortices. We then assessed the consequences of modulating motor excitability by applying single-pulse TMS over the primary motor cortex and measuring: 1) muscle responses with electromyography and 2) cerebral blood flow with PET. Low-frequency repetitive stimulation reduced muscle responses to a similar degree in both experiments. To map networks of brain regions in which activity changes reflected modulation of motor excitability, we generated t-statistical maps of correlations between reductions in muscle response and differences in cerebral blood flow. Low-frequency repetitive stimulation altered neural activity differently in both experiments. Neural modulation occurred in multiple brain regions after dorsal premotor cortex stimulation; these included motor regions in the frontal cortex as well as more associational regions in the parietal and prefrontal cortices. In contrast, neural modulation occurred in a smaller number of brain regions after primary motor cortex stimulation, many of these confined to the motor system. These findings are consistent with the known differences between the dorsal premotor and primary motor cortices in the extent of cortico-cortical anatomical connectivity in the monkey.
Distinct Roles of P2X Receptors in Modulating Glutamate Release at Different Primary Sensory Synapses in Rat Spinal Cord
Authors: Nakatsuka Terumasa , Tsuzuki Kenzo , Ling Jennifer X. , Sonobe Hideki , Gu Jianguo G.
Published: May 2006

Using spinal cord slice preparations and patch-clamp recordings in lamina II and lamina V regions, we tested a hypothesis that P2X receptor subtypes differentially modulate glutamate release from primary afferent terminals innervating different sensory regions. We found that activation of P2X receptors by α,β-methylene-ATP increased glutamate release onto >80% of DH neurons in both lamina regions. However, two distinct types of modulation, a transient and a long-lasting enhancement of glutamate release were observed. In lamina II recordings, >70% of the modulation was transient. In contrast, P2X receptor-mediated modulation was always long-lasting in lamina V. Pharmacologically, both transient and long-lasting types of modulation were blocked by 10 μM pyridxal-phospahte-6-azophenyl-2′,4′-disulphonic acid tetrasodium, a broad-spectrum P2X receptor antagonist. Transient modulation was not observed in the presence of 1 μM trinitrophenyl-ATP (TNP-ATP), a subtype-selective P2X receptor antagonist, suggesting that homomeric P2X3receptors may be involved in the transient modulation in lamina II. The long-lasting modulation remained in the presence of 1 μM TNP-ATP. Selective removal of P2X3-expressing afferent terminals by the targeting toxin saporin-conjugated isolectin B4 or surgical removal of superficial DH did not affect P2X receptor-mediated long-lasting modulation in lamina V. Taken together, these results suggest that P2X receptor subtypes play distinct roles in sensory processing in functionally different sensory regions.
GABA-Mediated Trophic Effect on Oligodendrocytes Requires Na-K-2Cl Cotransport Activity
Authors: Wang Hao , Yan Yiping , Kintner Douglas B. , Lytle Christian , Sun Dandan
Published: May 2006

The Na-K-2Cl cotransporter isoform1 (NKCC1) is present in many animal cells where it plays prominent roles in regulating cell volume and maintaining intracellular Cl–concentration ([Cl–]i) above electrochemical equilibrium. We show here that NKCC1 is present and active in cultured oligodendrocytes. Expression of NKCC1 in the rat spinal cord increased during development from postnatal day 6 through 21 in parallel with that of myelin basic protein. In cultured oligodendrocytes, 39% of the total K+(86Rb+) influx represented NKCC1 activity. Activation of GABAAreceptors with muscimol produced a reduction in intracellular Cl–content, cell shrinkage, and a stimulation of NKCC1 activity. Muscimol also triggered an increase in intracellular Ca2+, which depended on NKCC1 activity. Survival of oligodendrocytes following withdrawal of growth factors was enhanced by muscimol and this effect also required NKCC1 activity. Our results suggest that NKCC1 functions in oligodendrocytes to maintain [Cl–]iabove electrochemical equilibrium and that NKCC1 is required for GABAergic trophic effects.
Predicting Proenvironmental Behavior Cross-Nationally
Authors: Oreg Shaul , Katz-Gerro Tally
Published: May 2006

This article builds on Ajzen's theory of planned behavior and on Stern et al.'s value-belief-norm theory to propose and test a model that predicts proenvironmental behavior. In addition to relationships between beliefs, attitudes, and behaviors, we incorporate Inglehart's postmaterialist and Schwartz's harmony value dimensions as contextual antecedents at the national level. Structural equation modeling analyses of a 27-country sample provide almost full support for the mediation model. Postmaterialistic values, but not harmony, affect environmental concern; in turn, environmental concern, perceived threat, and perceived behavioral control affect willingness to sacrifice, which then affects a variety of proenvironmental behaviors. The findings emphasize the contribution of cultural conditions to the shaping of individuals'actions vis-à-vis environmental issues, alongside individual-level social-psychological variables.
Introduction
Authors: Garrioch David , Peel Mark
Published: May 2006

Social historians have generally regarded neighborhoods as crucial elements of the urban landscape in Europe, North America, and Australia. Introducing a collection of articles generated for a symposium on the history of urban neighborhoods, this discussion of concepts, key questions, and approaches suggests that a long-term and comparative view undermines a common narrative about growth and decline, or a straightforward distinction between early modern and modern neighborhoods. Instead, a survey of histories suggests that neighboring is best understood, in all periods, as a dynamic process, which may be triggered and reinforced rather than diminished by the processes commonly associated with modernity and increased mobility. The survey also suggests that the urban social relationships that constitute neighboring—and the problems and opportunities of proximity that they negotiate—form a consistent rhythm in city life.
Local Life in Working-Class Paris at the end of the Nineteenth Century
Authors: Faure Alain
Published: May 2006

This article questions the emphasis that many historians have placed on community and solidarity in nineteenth-century working-class neighborhoods, and the associated idea that these values were under-mined by improved housing, social welfare systems, urban transit, and growing links with the outside world. Taking late nineteenth-century Paris as a case study, it shows that working-class neighborhoods always contained strong internal tensions and that forced proximity did not necessarily create solidarity. Far from being communitarian in outlook, people had a strong sense of private life and of boundaries. Poverty and unstable employment made residential and daily mobility so high, well before mass transit arrived, that attachment to a single neighborhood was impossible. Neighborhood solidarities did exist, but they were only one small aspect of urban life.
Your Money or Your Self-Esteem: Threatened Egotism Promotes Costly Entrapment in Losing Endeavors
Authors: Zhang Liqing , Baumeister Roy F.
Published: May 2006

The present research explored egotism—maintaining favorable views of the self—as a motivation underlying entrapment in losing endeavors. Four studies suggested that threatened selfesteem would cause decision makers to invest and lose more money in a previously chosen course of action. Ego-threatened participants consistently lost more money than nonthreatened participants across diverse entrapping situations regardless of whether the outcome was ostensibly determined by luck (Experiments 1 and 4), ability (Experiment 2), or interpersonal competition (Experiment 3). Thus, pursuing favorable views of the self could be costly to decision makers' financial well-being and may produce self-defeating behaviors.
Increasing Acquaintanceship and Complementarity of Behavioral Styles and Personality Traits Among College Roommates
Authors: Markey Patrick M. , Kurtz John E.
Published: May 2006

Robert Carson's principle of complementarity asserts that the behavioral styles of interaction partners tend to complement each other by encouraging individuals to act opposite in terms of dominance and similar in terms of warmth. The principles of complementarity further hypothesize that as relationships progress through multiple interactions, the behavioral styles of its members will be altered to increase complementarity. To examine this acquaintanceship hypothesis, the behavioral styles and personalities of 102 college roommate dyads were assessed after living together for 2 weeks and again after living together for 15 weeks. Consistent with the acquaintanceship hypothesis, after 2 weeks the behavioral styles of roommates did not complement each other; however, after 15 weeks, the behavioral styles of roommates strongly complemented each other. In contrast to the change in complementarity observed in roommates' behavioral styles, participants' perceptions of their own personalities were relatively unaffected by the personalities of their roommates.
Does Social Identification Harm or Serve as a Buffer? The Impact of Social Identification on Anger After Experiencing Social Discrimination
Authors: Hansen Nina , Sassenberg Kai
Published: May 2006

Research on targets' affective reactions to social discrimination has not yet addressed self- and other-directed anger at the same time. Four studies tested the hypothesis that the perceived cause of negative feedback moderates the impact of social identification on self-directed anger. In Studies 1 and 2, high levels of social identification led to less self-directed anger when negative feedback was attributed to social discrimination but not when it was attributed either to other external causes or internally. In Study 3, a cross-lagged design showed that higher identification led to less self-directed anger when negative feedback was attributed to social discrimination but not the other way around. This effect was found using scenarios (Studies 1-3) and also when using the recollection of personal experiences to manipulate attribution (Study 4). These results indicate that following social discrimination, social identification protects the self and does not increase individual vulnerability.
Becoming the Harvard Man: Person-Environment Fit, Personality Development, and Academic Success
Authors: Harms P. D. , Roberts Brent W. , Winter David
Published: May 2006

The continuity and change of the needs and evaluations of the college environment and person-environment fit (PE fit) with the college environment were studied in a 4-year longitudinal study of students ( N = 191). Perceptions of the environment changed more dramatically than corresponding self-perceived needs. PE fit demonstrated moderate levels of consistency over the 4-year span, but no significant increases in mean levels were found over time. Antecedents to PE fit in the college environment included both intelligence and openness to experience. Outcomes associated with PE fit included changes in personality traits linked to openness to experience and higher academic achievement. The implications of the findings for personality development and the relationship of PE fit to successful outcomes are discussed.
Accounting and Washing
Authors: Pols Jeannette
Published: May 2006

This article analyzes how the recent call for accounting in health care interferes with daily care practice and raises the question of how accounting practices relate to the aim of good care. The most influential accounting methods in the Netherlands suggest ways for professionals to legitimize their activities. The analysis of washing patients in long-term mental health care shows that different styles of accounting evaluate and legitimize care while structuring notions of what good care is. A specific style of accounting enforces certain values but does not tell about the tragic or unexpected effects that come with it, nor does it provide a repertoire to deal with these. Thus, care practices incorporating specific styles of accounting remain dependent on forms of care that are not accountable or ask for new forms of reflexivity.
Countering the Loading-Dock Approach to Linking Science and Decision Making
Authors: Cash David W. , Borck Jonathan C. , Patt Anthony G.
Published: May 2006

This article provides a comparative institutional analysis between El Niño/Southern Oscillation (ENSO) forecasting systems in the Pacific and southern Africa with a focus on how scientific information is connected to the decision-making process. With billions of dollars in infrastructure and private property and human health and well-being at risk during ENSO events, forecasting systems have begun to be embraced by managers and firms at multiple levels. The study suggests that such systems need to consciously support the coproduction of knowledge. A critical component of such coproduction seems to be managing the boundaries between science and policy and across disciplines, scale, and knowledges to create information that is salient, credible, and legitimate to multiple audiences. This research suggests institutional mechanisms that appear to be useful in managing such boundaries, including mechanisms for structuring convening, translation, collaboration, and mediation functions.
The Impact of Concentrations of Religious Denominational Affiliations on the Rate of Currently Divorced in Counties in the United States
Authors: Mullins Larry C. , Brackett Kimberly P. , Bogie Donald W. , Pruett Daniel
Published: May 2006

This study examines the question Does the rate of currently divorced in counties in the United States vary inversely to the relative percentage of concentration of adherents of seven different religious denominational groupings—Catholic, Jewish, Mormon, conservative Protestant, moderate Protestant, liberal Protestant, and miscellaneous Protestant—within those counties? The analysis is based on data from the 1990 U.S. Census and the Glenmary Research Center that pertain to a 20% random sample of counties from each of the 50 states (i.e., 621 counties). The results show, controlling for other selected variables known to be associated with the likelihood of divorce, that higher divorced rates are significantly related to a lower concentration of moderate Protestants, miscellaneous Protestants, Catholics, and Mormons.
The Effect of Gamma Irradiation on Anterior Cruciate Ligament Allograft Biomechanical and Biochemical Properties in the Caprine Model at Time Zero and at 6 Months after Surgery
Authors: Schwartz Herbert E. , Matava Matthew J. , Proch Frank S. , Butler Charles A. , Ratcliffe Anthony , Levy Martin , Butler David L.
Published: May 2006

Background

High levels of gamma irradiation are required to eliminate the risk of bacterial and viral transmission during implantation of musculoskeletal allografts. The effects of high levels of gamma irradiation on anterior cruciate ligament allograft biomechanics are still not known.

Hypothesis

High-dose gamma irradiation (4 Mrad) adversely affects anterior cruciate ligament allograft biomechanics at surgery and at 6 months after surgery and affects biochemistry at 6 months.

Study Design

Controlled laboratory study.

Methods

Bilateral anterior cruciate ligament reconstructions were performed in 18 adult goats, with one knee receiving an irradiated patellar tendon allograft (4 Mrad) and the other receiving a frozen control allograft (0 Mrad). In 6 recipients (time zero group), graft pairs were tested immediately after sacrifice, and load relaxation of the femur-allograft-tibia preparation was measured during cyclic anterior displacement. Twelve recipients received bilateral anterior cruciate ligament reconstructions, staged 2 months apart, and were sacrificed a mean of 6 months postoperatively. Load relaxation and tensile failure testing were performed, followed by allograft biochemistry assessment.

Results

At time zero, irradiated grafts showed less load relaxation than did contralateral controls, but by 6 months, the trend had reversed because of decreases in control graft relaxation, with no changes in irradiated graft relaxation. By 6 months, irradiated grafts showed lower stiffness and maximum force compared to controls but no differences in modulus, maximum stress, or biochemistry.

Conclusion

High levels of gamma irradiation affect anterior cruciate ligament allograft subfailure viscoelastic and structural properties but not material or biochemical properties over time.

Clinical Relevance

Although high levels of gamma irradiation may inactivate infectious agents, this treatment is not a feasible clinical option because of altered allograft biomechanics.
The Spatial Model and the Senate Trial of President Clinton
Authors: Bertelli Anthony M. , Grose Christian R.
Published: May 2006

Most accounts of the Clinton Senate trial are based on legal theories and description or suggest that the Senate trial was sui generis, unrelated to regular Senate business. Alternatively, we argue that presidential removal trials can best be explained through a spatial voting model, with ideological estimates for senators best predicting the trial outcome. To examine these hypotheses, we generate (a) ideal-point estimates using Markov chain Monte Carlo methods on roll-call data as well as (b) text-based (wordscores) point estimates scaled from public statements. Our results support the spatial hypothesis, but not legal or idiosyncratic accounts. Moreover, the significant discrepancy between text- and vote-based estimates provides support for Mayhew’s contention that position taking for constituency benefit is rather costless. We conclude that when asked to be judges, senators, faced with multifarious political incentives, are more likely to act like legislators.
The Role of Group Consciousness in Political Participation Among Latinos in the United States
Authors: Sanchez Gabriel R.
Published: May 2006

There are approximately 40 million Latinos living in the United States, which represents 13.7% of the U.S. population. Despite the growing attention the newly titled largest minority group has yielded, there is still a large question of whether this community can translate demographics into political influence. This study attempts to add to this literature by testing dominant theories of political participation in conjunction with the concept of group consciousness utilizing the 1999 Kaiser/Post National Survey of Latinos. Through the use of measures for all dimensions of group consciousness across multiple Latino subgroups, this analysis helps to clarify the role of group consciousness in Latino political behavior. Through an examination of the relationship between group consciousness and political participation across both voting and Latino-specific activities, this study suggests that group consciousness is more meaningful in the context of political activities that are directly tied to the Latino community.
Dynamics of Diffusion
Authors: Sulkin Tracy , Evans Jillian
Published: May 2006

We examine patterns in campaign agendas for a sample of 1,141 House and Senate candidates in the 1984 to 1996 elections, using a content analysis of coverage of their campaigns in CQ Weekly Report’s “Special Election Issue” to extract each candidate’s priority issues. The results indicate that, contrary to some of the predictions in the broader literature on congressional campaigns and elections, these agendas are very diffuse, with a high level of diversity in themes across candidates, races, and time. We uncover evidence of systematic differences in the issue priorities highlighted by Democrats and Republicans, by House and Senate candidates, and by incumbents, challengers, and candidates for open seats. We also find substantial independence in the agenda choices of opposing candidates, of same-state copartisans, of candidates who run in multiple elections, and of same-district or -state candidates across time. These findings have important implications for understanding the role of campaigns in agenda setting and in the broader representative process.
Human complement receptor type 1–directed loading of tissue plasminogen activator on circulating erythrocytes for prophylactic fibrinolysis
Authors: Zaitsev Sergei , Danielyan Kristina , Murciano Juan-Carlos , Ganguly Kumkum , Krasik Tatiana , Taylor Ronald P. , Pincus Steven , Jones Steven , Cines Douglas B. , Muzykantov Vladimir R.
Published: May 2006

Plasminogen activators (PAs) are not used for thromboprophylaxis due to rapid clearance, bleeding, and extravascular toxicity. We describe a novel strategy that overcomes these limitations. We conjugated tissue-type PA (tPA) to a monoclonal antibody (mAb) against complement receptor type 1 (CR1) expressed primarily on human RBCs. Anti-CR1/tPA conjugate, but not control conjugate (mIgG/tPA), bound to human RBCs (1.2 × 103 tPA molecules/cell at saturation), endowing them with fibrinolytic activity. In vitro, RBC-bound anti-CR1/tPA caused 90% clot lysis versus 20% by naive RBCs. In vivo, more than 40% of anti-CR1/125I-tPA remained within the circulation (∼90% bound to RBCs) 3 hours after injection in transgenic mice expressing human CR1 (TgN-hCR1) versus less than 10% in wild-type (WT) mice, without RBC damage; approximately 90% of mIgG/125I-tPA was cleared from the circulation within 30 minutes in both WT and TgN-hCR1 mice. Anti-CR1/tPA accelerated lysis of pulmonary emboli and prevented stable occlusive carotid arterial thrombi from forming after injection in TgN-hCR1 mice, but not in WT mice, whereas soluble tPA and mIgG/tPA were ineffective. Anti-CR1/tPA caused 20-fold less rebleeding in TgN-hCR1 mice than the same dose of tPA. CR1-directed immunotargeting of PAs to circulating RBCs provides a safe and practical means to deliver fibrinolytics for thromboprophylaxis in settings characterized by a high imminent risk of thrombosis.
Identification of genic moss SSR markers and a comparative analysis of twenty-four algal and plant gene indices reveal species-specific rather than group-specific characteristics of microsatellites
Authors: von Stackelberg Mark , Rensing Stefan A , Reski Ralf
Published: May 2006

Background

The moss Physcomitrella patens is an emerging model in comparative plant science. At present, the Physcomitrella genome is sequenced at the Joint Genome Institute (USA). In this study we present our results on the development of expressed sequence tag-derived microsatellite markers for Physcomitrella patens, their classification and applicability as genetic markers on the intra- as well as on the interspecies level. We experienced severe restrictions to compare our results on Physcomitrella with earlier studies for other plant species due to varying microsatellite search criteria and a limited selection of analysed species. As a consequence, we performed a side by side analysis of expressed sequence tag-derived microsatellites among 24 plant species covering a broad phylogenetic range and present our results on the observed frequencies.

Results

We identified 3,723 microsatellites using the software MISA in a non-redundant Physcomitrella expressed sequence tag database comprising more than 37 megabases of nucleotide information. For 2,951 microsatellites appendant primer sequences have been derived. PCR of 376 microsatellites yielded 88 % successful amplicons and over 30 % polymorphisms between two Physcomitrella accessions. The polymorphism information content of 64 microsatellites based on 21 different Physcomitrella accessions was comparably high with a mean of 0.47 +/- 0.17. Of the 64 Physcomitrella microsatellite markers, 34 % respectively 79.7 % revealed cross-species applicability in two closely related moss species.

In our survey of two green algae, two mosses, a fern, a fern palm, the ginkgo tree, two conifers, ten dicots and five monocots we detected an up to sevenfold variation in the overall frequency with a minimum of 37 up to maximal 258 microsatellites per megabase and a high variability among the different microsatellite class and motif frequencies. Numerous species-specific microsatellite frequencies became evident and several deviations to earlier reports were ascertained.

Conclusion

With the Physcomitrella microsatellite marker set a valuable tool has been made available for further genetic and genomic applications on the intra- as well as on the interspecies level. The comparative survey of expressed sequence tag-derived microsatellites among the plant kingdom is well suited for a classification of future studies on plant microsatellites.
Insight dimensions and cognitive function in psychosis: a longitudinal study
Authors: Cuesta Manuel J , Peralta Victor , Zarzuela Amalia , Zandio Maria
Published: May 2006

Background

It has been reported that lack of insight is significantly associated with cognitive disturbance in schizophrenia. This study examines the longitudinal relationships between insight dimensions and cognitive performance in psychosis.

Methods

Participants were 75 consecutively admitted inpatients with schizophrenia, affective disorder with psychotic symptoms or schizoaffective disorder. Assessments were conducted at two time points during the study: at the time of hospital discharge after an acute psychotic episode and at a follow-up time that occurred more than 6 months after discharge. A multidimensional approach of insight was chosen and three instruments for its assessment were used: the Scale to Assess Unawareness of Mental Disorder (SUMD), three items concerning insight on the Assessment and Documentation in Psychopathology (AMDP) system and the Insight and Treatment Attitudes Questionnaire. The neuropsychological battery included a wide range of tests that assessed global cognitive function, attention, memory, and executive functions.

Results

After conducting adequate statistical correction to avoid Type I bias, insight dimensions and cognitive performance were not found to be significantly associated at cross-sectional and longitudinal assessments. In addition, baseline cognitive performance did not explain changes in insight dimensions at follow-up. Similar results were found in the subset of patients with schizophrenia (n = 37). The possibility of a Type II error might have increased due to sample attrition at follow-up.

Conclusion

These results suggest that lack of insight dimensions and cognitive functioning may be unrelated phenomena in psychosis.
End of life content in geriatric textbooks: what is the current situation?
Authors: Wu Huei Yaw , Malik Farida A , Higginson Irene J
Published: May 2006

Background

Physicians caring for elderly people encounter death and dying more frequently than their colleagues in most other disciplines. Therefore we sought to examine the end-of-life content in popular geriatric textbooks and determine their usefulness in helping geriatricians manage patients at the end of their lives.

Methods

Five popular geriatric textbooks were chosen. Chapters on Alzheimer's disease, stroke, chronic heart failure, chronic obstructive pulmonary disease and lung cancer were examined because of their high mortality rates among the elderly patients. Text relevant to end-of-life care was highlighted. Two reviewers independently coded text into 10 pre specified domains and rated them for the presence of end-of-life information. Content was rated as absent, minimally helpful, or helpful. The proportion of helpful information was calculated.

Results

The textbook with the best end-of-life coverage contained 38% helpful information, the worst had only 15% helpful information. Minimally helpful information ranged from 24% to 50%. As much as 61% of the content in one textbook contained no helpful information at all. Of the ten domains, epidemiology, disease progression and prognostic factors were fairly well covered. Information on advance care planning, ethical issues, decision making and effects of death and dying on patient's family were generally lacking under the individual diseases though they were covered as general topics in other parts of the textbooks. All except one textbook dedicated a chapter to the care of the dying.

Conclusion

This study showed that end-of-life content in geriatric textbooks differed significantly. Most of the textbooks lack good coverage on end-of-life care and more can be done to improve on this.
Minor psychiatric disorders among Brazilian ragpickers: a cross-sectional study
Authors: da Silva Marcelo Cozzensa , Fassa Anaclaudia Gastal , Kriebel David
Published: May 2006

Background

Ragpickers are informal workers who collect recyclable materials to earn a small wage. Their life and working conditions are extremely difficult. We examined minor psychiatric disorders (MPD) among a cohort of ragpickers in Pelotas, a city in southern Brazil.

Methods

Ragpickers were matched by sex, age, and years of schooling with a sample of non-ragpickers from the same poor neighborhoods. The cross-sectional study gathered data by interview on 990 individuals in 2004. MPD were assessed using a standard self-reporting questionnaire, the SRQ-20.

Results

The prevalence of MPD among ragpickers was 44.7%, higher than reported by neighborhood controls (33.6%; p < 0.001). MPD were more common among females, those of lower economic level, smokers and alcoholics. Among occupational characteristics, MPD prevalence was associated with frequent static postures, low job satisfaction and recent work accidents.

Conclusion

Ragpickers more frequently report MPD than other poor workers living in the same neighborhoods, with many of the same life conditions. Improving the work lives of these precarious workers should address not only the physical hazards of their jobs but their mental and emotional health as well.
The effect of pregnancy and lactation on bone mineral density in fluoride-exposed rats
Authors: Yildiz Mustafa , Oral Baha
Published: May 2006

Fluoride increases metabolic turnover of the bone in favour of bone formation. Excessive intake of fluoride may lead to pathological changes in teeth and bones: dental and skeletal fluorosis. In this study, we investigated the effect of pregnancy and lactation on bone mineral density (BMD) in fluoride-exposed rats. Female Wistar rats were given commercially available spring water with 100 ppm fluoride (N-8), or without addition (N-8) for 18 weeks. At 16 weeks of age, four female rats and one male rat were kept in a cage for 5 days; all females were successfully impregnated. BMD was measured at 16 weeks of age, on the first day postpartum, and at the end of lactation. Spinal BMD was significantly higher in fluoride-exposed rats than control (P≤0.05), but there were no differences in femoral BMD (P-0.670). During pregnancy, spinal BMD and femoral BMD were not significantly changed in fluoride-exposed rats, whereas BMD of the spine was significantly decreased in the control rats (P-0.013), but not in the femur. During lactation, BMD was significantly decreased at the two regions compared to initial values (P≤0.05) in both groups. This study shows that pregnancy has no effect on bone, but lactation has a decreasing effect on BMD in fluoride-exposed rats.
Effects of v-3 essential fatty acids against formaldehyde-induced nephropathy in rats
Authors: Zararsiz Ismail , Sonmez Mehmet Fatih , Yilmaz H. Ramazan , Tas Ufuk , Kus Ilter , Kavakli Ahmet , Sarsilmaz Mustafa
Published: May 2006

The aim of this study was to examine the toxicity of formaldehyde (FA) on the kidney and the protective effects of v-3 essential fatty acids against these toxic effects. Twenty-one male Wistar rats were divided into three groups. Rats in Group I comprised the controls, while the rats in Group II were injected every other day with FA. Rats in Group III received v-3 fatty acids daily while exposed to FA. At the end of the 14-day experimental period, all rats were killed by decapitation and the kidneys removed. Some of the kidney tissue specimens were used for determination of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activities, and malondialdehyde (MDA) levels. The remaining kidney tissue specimens were used for light microscopic evaluation. The levels of SOD and GSH-Px were significantly decreased, and MDA levels were significantly increased in rats treated with FA compared with those of the controls. Furthermore, in the microscopic examination of this group, glomerular and tubular degeneration, vascular congestion and tubular dilatation were observed. However, increased SOD and GSH-Px enzyme activities, and decreased MDA levels were detected in the rats administered v-3 fatty acids while exposed to FA. Additionally, kidney damage caused by FA was decreased and structural appearance was similar to that of the control rats in this group. In conclusion, it was determined that FA-induced kidney damage was prevented by administration of v-3 essential fatty acids.
Lethal acute lung injury and hypoglycemia after subcutaneous administration of monochloroacetic acid
Authors: Kato Junko , Dote Tomotaro , Shimizu Hiroyasu , Shimbo Yukari , Fujihara Michiko , Kono Koichi
Published: May 2006

Hypoglycemia is suspected in the acute lethal toxicity induced by cutaneous exposure to monochloroacetic acid (MCA). Although it has been shown that hepato-renal dysfunction is involved, the mechanism and the target organs that directly affect mortality remain to be determined. We suspected respiratory failure as a main cause of death in some reported cases. We investigated dose-response effects, hypoglycemia, and lung injury in rats exposed to MCA. Serum glucose, blood gases, and parameters of alveolar injury in bronchoalveolar lavage fluid (BALF) were analysed 2 and 4 h after subcutaneous administration of MCA (108, 135 or 163 mg/kg). Apparent pulmonary injury and hypoglycemia were not identified 2 h after administration, but lactate dehydrogenase (LDH) and total cells in BALF were dose-dependently increased; and severe hypoglycemia was identified 4 h after administration. Blood gas analysis showed remarkable alveolar gas dysfunction as exchange in the 163 mg/kg group. Thus, hypoglycemia and lung injury appear to cause death in response to MCA exposure.
Socio-economic impacts of microfinance and repayment performance: a case study of the Small Enterprise Foundation, South Africa
Authors: Hietalahti Johanna , Linden Mikael
Published: May 2006

The socio-economic impacts of microcredits on women's welfare were studied in northeastern South Africa using a qualitative semi-structured interviewing method. The study focuses particularly on the benefits, disadvantages and challenges obtained from The Small Enterprise Foundation (SEF) microcredit village programmes (Micro Credit Programme (MCP) and the T'shomisano Credit Programme (TCP)). Impacts of microcredits and a comparison of two programmes were analysed on a household level. The results revealed that a number of the poorest women have been released from deepest poverty through the opportunities provided by SEF. The MCP clients, who tend to have a better starting point, seemed to be more educated, able to diversify and improve their businesses as well as being more capable of protecting themselves against vulnerability than the poorer TCP clients. Many repayment problems were caused by group heterogeneity. Particularly in the MCP, the incentive to free-ride seemed to be a problem phenomenon. These drawbacks demonstrate that there are still some unresolved disadvantages in the programmes.
Breast Cancer Risk Estimates for Relatives of White and African American Women With Breast Cancer in the Women's Contraceptive and Reproductive Experiences Study
Authors: Simon Michael S. , Korczak Jeannette F. , Yee Cecilia L. , Malone Kathleen E. , Ursin Giske , Bernstein Leslie , McDonald Jill A. , Deapen Dennis , Strom Brian L. , Press Michael F. , Marchbanks Polly A. , Burkman Ronald T. , Weiss Linda K. , Schwartz Ann G.
Published: May 2006

Purpose

Family history is a well-recognized risk factor for breast cancer. Familial aggregation and segregation analyses have estimated breast cancer risk based on family history primarily for white women; such information is limited for African American (AA) women. The purpose of this report is to update breast cancer risk estimates associated with a family history of breast cancer for white and AA women.

Methods

We used family cancer history from 2,676 white and 1,525 AA women with breast cancer (probands) in the population-based National Institute of Child Health and Human Development's Women's Contraceptive and Reproductive Experiences (CARE) Study to estimate age-specific breast cancer risks in their first degree adult female relatives. Cumulative hazard curves were calculated for relatives of all probands using Cox proportional hazards models, and were stratified by the proband's race and age at diagnosis and number of relatives affected.

Results

Breast cancer risks for white and AA women with a family history of the disease are similar through age 49 years, but diverge afterwards, with higher risks by age 79 in white women than in AA women (17.5% [SE, 0.9%] v 12.2% [SE, 1.1%]; P < .001). These risks increase as the number of affected first degree relatives increases, reaching 25.2% (SE, 3.4%) and 16.9% (SE, 4.0%) in white and AA women with more than one affected relative, respectively (P = .3).

Conclusion

We found age-related racial differences in breast cancer risk in women with a family history of breast cancer and have updated risk estimates for white and AA women for clinical use.
PML nuclear bodies are highly organised DNA-protein structures with a function in heterochromatin remodelling at the G2 phase
Authors: Luciani J. J. , Depetris D. , Usson Y. , Metzler-Guillemain C. , Mignon-Ravix C. , Mitchell M. J. , Megarbane A. , Sarda P. , Sirma H. , Moncla A. , Feunteun J. , Mattei M.-G.
Published: May 2006

We have recently demonstrated that heterochromatin HP1 proteins are aberrantly distributed in lymphocytes of patients with immunodeficiency, centromeric instability and facial dysmorphy (ICF) syndrome. The three HP1 proteins accumulate in one giant body over the 1qh and 16qh juxtacentromeric heterochromatins, which are hypomethylated in ICF. The presence of PML (promyelocytic leukaemia) protein within this body suggests it to be a giant PML nuclear body (PML-NB). The structural integrity of PML-NBs is of major importance for normal cell functioning. Nevertheless, the structural organisation and the functions of these nuclear bodies remain unclear. Here, we take advantage of the large size of the giant body to demonstrate that it contains a core of satellite DNA with proteins being organised in ordered concentric layers forming a sphere around it. We extend these results to normal PML-NBs and propose a model for the general organisation of these structures at the G2 phase. Moreover, based on the presence of satellite DNA and the proteins HP1, BRCA1, ATRX and DAXX within the PML-NBs, we propose that these structures have a specific function: the re-establishment of the condensed heterochromatic state on late-replicated satellite DNA. Our findings that chromatin-remodelling proteins fail to accumulate around satellite DNA in PML-deficient NB4 cells support a central role for PML protein in this cellular function.
On the Asymptotic Optimality of a Simple On-Line Algorithm for the Stochastic Single-Machine Weighted Completion Time Problem and Its Extensions
Authors: Chou Mabel C. , Liu Hui , Queyranne Maurice , Simchi-Levi David
Published: May 2006

We consider the stochastic single-machine problem, when the objective is to minimize the expected total weighted completion time of a set of jobs that are released over time. We assume that the existence and the parameters of each job including its release date, weight, and expected processing times are not known until its release date. The actual processing times are not known until processing is completed. We analyze the performance of the on-line nonpreemptive weighted shortest expected processing time among available jobs (WSEPTA) heuristic. When a scheduling decision needs to be made, this heuristic assigns, among the jobs that have arrived but not yet processed, one with the largest ratio of its weight to its expected processing time. We prove that when the job weights and processing times are bounded and job processing times are mutually independent random variables, WSEPTA is asymptotically optimal for the single-machine problem. This implies that WSEPTA generates a solution whose relative error approaches zero as the number of jobs increases. This result can be extended to the stochastic flow shop and open shop problems, as well as models with stochastic job weights.
On the Asymptotic Validity of Fully Sequential Selection Procedures for Steady-State Simulation
Authors: Kim Seong-Hee , Nelson Barry L.
Published: May 2006

We present fully sequential procedures for steady-state simulation that are designed to select the best of a finite number of simulated systems when “best” is defined by the largest or smallest long-run average performance. We also provide a framework for establishing the asymptotic validity of such procedures and prove the validity of our procedures. An example based on the M/M/1 queue is given.
Design and Control of a Large Call Center: Asymptotic Analysis of an LP-Based Method
Authors: Bassamboo Achal , Harrison J. Michael , Zeevi Assaf
Published: May 2006

This paper analyzes a call center model with m customer classes and r agent pools. The model is one with doubly stochastic arrivals, which means that the m-vector λ of instantaneous arrival rates is allowed to vary both temporally and stochastically. Two levels of call center management are considered: staffing the r pools of agents, and dynamically routing calls to agents. The system manager’s objective is to minimize the sum of personnel costs and abandonment penalties. We consider a limiting parameter regime that is natural for call centers and relatively easy to analyze, but apparently novel in the literature of applied probability. For that parameter regime, we prove an asymptotic lower bound on expected total cost, which uses a strikingly simple distillation of the original system data. We then propose a method for staffing and routing based on linear programming (LP), and show that it achieves the asymptotic lower bound on expected total cost; in that sense the proposed method is asymptotically optimal.
Optimal Policy for a Multiechelon Inventory System with Remanufacturing
Authors: DeCroix Gregory A.
Published: May 2006

We analyze a multiechelon inventory system with inventory stages arranged in series. In addition to traditional forward material flows, used products are returned to a recovery facility, where they can be stored, disposed, or remanufactured and shipped to one of the stages to re-enter the forward flow of material. This system combines the key elements of two simpler systems: the series system studied by Clark and Scarf (1960) and the single-stage remanufacturing systems studied by Simpson (1978) and Inderfurth (1997). We focus on identifying the structure of the optimal remanufacturing/ordering/disposal policy for such a system. In particular, we investigate whether the optimal policy inherits the basic structural properties of the simpler systems. We show that if remanufactured items flow into the most upstream stage, then this is the case. Specifically, the system can be solved by decomposition into a sequence of single-stage systems, with each downstream stage following an echelon base-stock policy and the most upstream stage following a three-parameter policy with a simple (and intuitive) structure. We show that similar results hold when remanufactured products flow into a downstream stage; however, in this case some modifications must be made. In particular, the definition of echelon inventory must be adjusted for stages upstream of the remanufacturing stage, and disposal of used items can no longer be allowed. We also compare the information required for managing this system to that required in the Clark and Scarf or Inderfurth settings, and we point out how the requirements are somewhat different depending on whether remanufacturing occurs upstream or downstream.
How Can Osteoporosis Patients Benefit More from Their Therapy? Adherence Issues with Bisphosphonate Therapy
Authors: Gold Deborah T , Alexander Ivy M , Ettinger Mark P
Published: May 2006

Objective:

To review the evidence on adherence with bisphosphonates and evolving dosing strategies for osteoporosis treatment.

Data Sources:

Articles were identified by searching MEDLINE (1975–December 2005) using the following terms: osteoporosis, postmenopausal, fracture, adherence, compliance, persistence, drug therapy, bisphosphonates, alendronate, risedronate, ibandronate, and zoledronate. Additional data included bibliographies from identified articles.

Study Selection and Data Extraction:

All pertinent English-language articles that discussed adherence issues in patients with osteoporosis were included. Both those that reviewed overall issues of medication adherence in osteoporosis and those that focused specifically on adherence to bisphosphonates were included, as were articles that addressed strategies for overcoming nonadherence.

Data Synthesis:

Inadequate diagnosis and treatment of osteoporosis result in a higher risk of fractures than is necessary. Even patients who are diagnosed and beginning treatment often do not persist with their osteoporosis medication because they perceive their fracture risk to be low and, given the asymptomatic nature of osteoporosis, do not experience the benefit of symptom reduction after taking the drugs. Factors that affect adherence to osteoporosis therapy include drug costs, adverse effects, dosing frequency, disease education, patient follow-up, and patient involvement in treatment decisions.

Conclusions:

By considering and implementing strategies that can improve adherence and persistence, primary care providers and pharmacists (via counseling) may enhance long-term outcomes for patients with osteoporosis.