bluuebunny/crossref_metadata_2025 huggingface dataset:
Evidence of and for what?
Authors: Csordas Thomas J.
Published: November 2004

What kind of language game do we initiate by making ‘evidence’ the focus of methodological discussion? Drawing on the example set by Wittgenstein, our first step might well be to consider the senses in which we can use the notion of evidence in anthropological writing. These senses must be different if we are asking for evidence of the existence or nature of a phenomenon (such as, for example, totemism or kinship), or evidence to test a hypothesis from the standpoint either of validation or falsification. The sense must also be different if evidence is to be understood in a juridical sense or an experimental sense. Again, evidence may be understood to be synonymous with data, or could imply a sense of what is evident, or even self-evidence - the immediacy of experience as examined by phenomenology. To determine how these different senses of evidence color our understanding of the ethnographic enterprise is the ultimate goal of this discussion.
Imparting Self-Control Skills to Decrease Aggressive Behavior in a 12-Year-Old Boy
Authors: Ronen Tammie
Published: November 2004

•Summary: This paper presents the case of a 12-year-old boy with oppositional defiant disorder (ODD) who demonstrated no interest in participating in therapy. The aims of the paper were to present a multiple therapy design as an effective measurement for social workers to use in their regular intervention process; to learn about the relative effectiveness of three common methods for addressing ODD (behavior therapy being used in teacher supervision and parental counseling and cognitive therapy being used in the child’s individual therapy); and to present a self-control model for improving the child’s behavior.

•Findings: The case study pointed to the efficacy of the self-control model for helping the child change. Therapy facilitated a significant decrease in the child’s disruptive behavior as well as a significant increase in the child’s self-control and social interaction. Also, the case study presented the feasibility of the single case design as an effective way for social workers to assess and evaluate their intervention.

•Applications: The presented case study highlighted the ability of social workers:

1. to supervise parents and teachers as important change agents in the child’s environment;

2. to use the single case design in daily intervention; and

3. to utilize cognitive behavioral therapy as an effective method for change.

The efficacy of the intervention pinpointed the need to apply the proposed methods for other problems as well.
Relations in Foster Care
Authors: Mosek Atalia
Published: November 2004

•Summary: This article explores the values, knowledge, policy and practice of three different programs of foster care in Israel and their implications for the experiences of all involved: children, parents, foster parents and social workers.

•Findings: An innovative methodology is used, whereby social work students collect data. Analysis of this qualitative data collected through semi-structured interviews clarifies the issues that are of major concern for foster children, parents, foster parents and foster workers. A connection is made between the service models that support detached, complementary or reciprocal relations and experiences in care.

•Applications: The article established the viewpoint that foster care is a creation of a new familial system that needs to deal with issues of power and create reciprocal relations amongst its partners. The conditions necessary for successful care are highlighted.
Ethical Practice in the Contemporary Human Services
Authors: Lonne Bob , Mcdonald Catherine , Fox Tricia
Published: November 2004

•Summary: This paper examines the findings of an exploratory study of emerging ethical issues and practices reported by a sample of human service managers and practitioners in public and non-profit agencies in Queensland, Australia.

•Findings: The contemporary context in which human services are delivered in Western societies is characterized by increased marketization, contractualism and managerialist practices, all of which entail different ethical values from those traditionally embraced by the social work profession. Utilizing qualitative and quantitative methodologies, this research identifies current and emerging challenges to ethical practice and existing organizational responses to it. Widespread concern about the negative aspects of changed structural arrangements on ethical practice in the contemporary human services is highlighted. Differences in the ways in which organizations and practitioners are responding to these changes are examined. The limitations of existing approaches and ethics codes are noted.

•Applications: Implications for organizations, practitioners and educators are explored, and more pro-active management and training strategies are advocated. Further research is required to identify the often-understated negative effects on ethical practice of the market-based reforms of human service structures and processes.
Drawing out emotions: the use of participant-produced drawings in qualitative inquiry
Authors: Kearney Kerri S. , Hyle Adrienne E.
Published: November 2004

In this article we outline the use of participant-produced drawings as part of a larger study that examined the emotional impact of change on individuals in an educational institution (Kearney, 2002; Kearney and Hyle, 2003). Both the participants’and the researchers’perspectives on the drawing methodology, as used in this study, provide the foundation for our findings that drawings: 1) create a path toward feelings and emotions, 2) lead to a more succinct presentation of participant experiences, 3) require additional verbal interpretation by the participant for accuracy, 4) are unpredictable as a tool for encouraging participation in the research, 5) combat researcher biases when left unstructured, 6) are affected by the amount of researcher-imposed structure in the scope of how they could be interpreted, and 7) help to create triangulation of study data.
New Bayesian Model Updating Algorithm Applied to a Structural Health Monitoring Benchmark
Authors: Ching Jianye , Beck James L.
Published: November 2004

A new two-step approach for probabilistic structural health monitoring is presented, which involves modal identification followed by damage assessment using the pre and post-damage modal parameters based on a new Bayesian model updating algorithm. The new approach aims to attack the structural health monitoring problems with incomplete modeshape information by including the underlying full modeshapes of the system as extra random variables, and by employing the Expectation-Maximisation algorithm to determine the most probable parameter values. The non-concave non-linear optimisation problem associated with incomplete modeshape cases is converted into two coupled quadratic optimisation problems, so that the computation becomes simpler and more robust. We illustrate the new approach by analysing the Phase II Simulated Benchmark problems sponsored by the IASC-ASCE Task Group on Structural Health Monitoring. The results of the analysis show that the probabilistic approach is able to successfully detect and locate the simulated damage involving stiffness loss in the braces of the analytical benchmark model based on simulated ambient-vibration data.
Experimental Damage Identification of Carbon/Epoxy Composite Beams Using Curvature Mode Shapes
Authors: Hamey Cole S. , Lestari Wahyu , Qiao Pizhong , Song Gangbing
Published: November 2004

Many composite materials and structures are susceptible to defects, which can significantly reduce the strength of structures and may grow to failure. To avoid the catastrophic failure of structures, development of a reliable method of structural health monitoring is one of the most important keys in maintaining the integrity and safety of structures. Dynamic response-based damage detection offers a simple procedure as an alternative to the conventional nondestructive evaluation techniques. However, this technique depends on the quality of measured data for its identification accuracy. In this article, experimental aspects of dynamic response-based damage detection technique on carbon/ epoxy composites are addressed. Smart piezoelectric materials are used as sensors or actuators to acquire the curvature modes of structures. These materials are surface-bonded to the beams. An impulse hammer is used as an actuating source as well. Four types of damage detection algorithms are evaluated for several possible damage configurations with two different excitation sources. The quality of damage identification with the four different detection algorithms is discussed. These experimental damage identification techniques using curvature modes and piezoelectric materials can be effectively used in damage detection and health monitoring of composite structures.
The Influence of Law in the Supreme Court’s Search-and-Seizure Jurisprudence
Authors: Kritzer Herbert M. , Richards Mark J.
Published: November 2004

In this research note/replication, we apply the construct of jurisprudential regimes as described in our recent article to the jurisprudential area of search and seizure. Given the centrality of this area of Supreme Court decision making in the core studies supporting the attitudinal model, replicating our analysis of the jurisprudential regime construct in this area provides an important test of the concept. Our results produce strong support for the proposition that post-Mapp decision making can be separated into distinct regimes, with a set of important cases decided in 1983-1984 demarcating the regimes. The predictors of decisions in the two periods are consistent with the types of changes one would expect the regime shift to produce. Our findings challenge the attitudinalists’proposition that there is at best negligible statistical evidence that law influences Supreme Court decision making.
Revisiting the Two Presidencies
Authors: Marshall Bryan W. , Pacelle Richard L.
Published: November 2004

Recent scholarly attention has considerably advanced our understanding of executive orders. We argue that executive orders represent a valuable opportunity to assess the relevance of the two presidencies and the distinction between foreign and domestic policies. The over-time analysis (1953-1997) demonstrates significant differences in the effects for most of the variables explaining executive orders depending on the issue area. For example, we find that the president’s share of congressional party seats significantly affects executive orders on domestic policy, but no such effects are found on foreign policy. This result, as well as many others in the analysis, illustrates that factors shaping the executive’s ability to influence policy in Congress differ substantially in their effects on domestic as compared to foreign policy executive orders. We infer from our analysis that the two-presidencies distinction remains a useful one, at least for understanding executive orders.
Congenital and Acquired Thrombocytopenia
Authors: Cines Douglas B. , Bussel James B. , McMillan Robert B. , Zehnder James L.
Published: November 2004

The diagnosis and management of thrombocytopenia is a growing component in the practice of hematology. The frequency with which hematologists are called in consultation for thrombocytopenia continues to increase with the advent of routine automated platelet determinations and the introduction of new medications. For most patients, such as those with inherited and auto-immune thrombocytopenia, emphasis is focused on efforts to treat or forestall bleeding without excess drug-induced toxicity or burden to the patient. However, in disorders such as heparin-induced thrombocytopenia (HIT), avoidance of thrombotic complications is the key to management. In this chapter, we provide the pediatric and adult hematologist with new insights into the pathogenesis and recognition of congenital inherited thrombocytopenias (CTP), a hitherto difficult to comprehend constellation of clinical entities. We also highlight new approaches to the diagnosis and treatment of two of the more common thrombocytopenic conditions encountered in practice, autoimmune or idiopathic thrombocytopenic purpura (ITP) and HIT.

In Section I, Dr. James Bussel discusses CTPs and their distinction from childhood ITP. He emphasizes the clinical features that enable the pediatrician and hematologist to suspect the diagnosis of CTP and those that are of use to subcategorize the various entities, where possible. He also emphasizes newer molecular markers that afford definitive diagnosis in some cases and provide insight into platelet production. This section highlights the characteristic associated findings and differences in the natural history and approaches to management of the various entities.

In Section II, Dr. Robert McMillan discusses adult chronic ITP. He revisits the utility of platelet antibody determination in diagnosis and review new insights into pathogenesis. The role of Helicobacter pylori infection and the timing of splenectomy in the management of acute and emergent ITP are examined. New insights into the natural history of ITP post-splenectomy and management strategies for patients with severe, chronic, refractory ITP are discussed.

In Section III, Dr. James Zehnder updates us on HIT. He emphasizes new insights into the clinical presentation and pathogenesis of this condition. He critically reviews the utility of laboratory testing for heparin-dependent antibodies. Recent studies on the use of direct thrombin inhibitors are examined and the management of cardiopulmonary bypass surgery in patients with HIT is discussed.
Liver Kupffer cells rapidly remove red blood cell–derived vesicles from the circulation by scavenger receptors
Authors: Willekens Frans L. A. , Werre Jan M. , Kruijt J. Kar , Roerdinkholder-Stoelwinder Bregt , Groenen-Döpp Yvonne A. M. , van den Bos Annegeet G. , Bosman Giel J. C. G. M. , van Berkel Theo J. C.
Published: November 2004

Previous studies have shown that during the lifespan of red blood cells (RBCs) 20% of hemoglobin is lost by shedding of hemoglobin-containing vesicles. However, the fate of these vesicles is unknown. To study this fate we used a rat model, after having established that rat RBCs lose hemoglobin in the same way as human RBCs, and that RBC-derived vesicles are preferentially labeled by \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{Na}_{2}^{51}\) \end{document} CrO4. Such labeled vesicles were injected into recipient rats. Within 5 minutes, 80% of the radioactivity was cleared from the circulation with a concomitant uptake by the liver of 55% of the injected dose. After 30 minutes, Kupffer cells contained considerable amounts of hemoglobin and were shown to be responsible for 92% of the liver uptake. Vesicle clearance from the blood as well as liver uptake were significantly inhibited by preinjection of the scavenger-receptor ligands polyinosinic acid and phosphatidylserine. We conclude that in rats Kupffer cells rapidly remove RBC-derived vesicles from the circulation, mainly by scavenger receptors. The same mechanism is likely to be responsible for the elimination of human RBC vesicles, thereby constituting an important pathway for the breakdown of RBCs in humans.
Vascular endothelial growth factor promotes sensitivity to ultraviolet B–induced cutaneous photodamage
Authors: Hirakawa Satoshi , Fujii Seishiro , Kajiya Kentaro , Yano Kiichiro , Detmar Michael
Published: November 2004

Acute ultraviolet B (UVB) irradiation of the skin results in erythema, vasodilation, edema, and angiogenesis, which is associated with the expression of vascular endothelial growth factor (VEGF) by epidermal keratinocytes. It is unclear, however, whether VEGF is required for the damage or repair process that occurs in the skin on UVB exposure. We subjected transgenic mice that overexpress VEGF, and their wild-type littermates, to graded doses of acute UVB irradiation. The skin of VEGF-overexpressing mice was highly photosensitive and became erythematic when exposed to half the UVB dose required to induce erythema in wild-type mice. Erythema was associated with proliferating dermal endothelial cells, cutaneous edema, and inflammatory cell infiltration. When subjected to 10 weeks of low-level UVB irradiation, no major changes were observed in wild-type mice, whereas VEGF transgenic mice developed skin damage associated with degradation of the dermal matrix and enhanced vascularization. Systemic treatment with an anti–VEGF blocking antibody reduced the sensitivity of wild-type mice to acute UVB irradiation without inhibiting post-UVB repair. Our results reveal that VEGF promotes the cutaneous damage that occurs after UVB exposure and that the VEGF signaling pathway might serve as a novel target for the prevention of UVB-induced photodamage.
Factor IX variants improve gene therapy efficacy for hemophilia B
Authors: Schuettrumpf Joerg , Herzog Roland W. , Schlachterman Alexander , Kaufhold Antje , Stafford Darrel W. , Arruda Valder R.
Published: November 2004

Intramuscular injection of adeno-associated viral (AAV) vector to skeletal muscle of humans with hemophilia B is safe, but higher doses are required to achieve therapeutic factor IX (F.IX) levels. The efficacy of this approach is hampered by the retention of F.IX in muscle extracellular spaces and by the limiting capacity of muscle to synthesize fully active F.IX at high expression rates. To overcome these limitations, we constructed AAV vectors encoding F.IX variants for muscle- or liver-directed expression in hemophilia B mice. Circulating F.IX levels following intramuscular injection of AAV-F.IX-K5A/V10K, a variant with low-affinity to extracellular matrix, were 2-5 fold higher compared with wild-type (WT) F.IX, while the protein-specific activities remained similar. Expression of F.IX-R338A generated a protein with 2- or 6-fold higher specific activity than F.IX-WT following vector delivery to skeletal muscle or liver, respectively. F.IX-WT and variant forms provide effective hemostasis in vivo upon challenge by tail-clipping assay. Importantly, intramuscular injection of AAV-F.IX variants did not trigger antibody formation to F.IX in mice tolerant to F.IX-WT. These studies demonstrate that F.IX variants provide a promising strategy to improve the efficacy for a variety of gene-based therapies for hemophilia B.
Regulation of tissue factor–induced signaling by endogenous and recombinant tissue factor pathway inhibitor 1
Authors: Ahamed Jasimuddin , Belting Mattias , Ruf Wolfram
Published: November 2004

Tissue factor (TF) triggers upstream coagulation signaling via the activation of protease-activated receptors (PARs) of relevance for inflammation and angiogenesis. TF pathway inhibitor 1 (TFPI-1) is the physiologic inhibitor of TF-initiated coagulation, but its role in regulating TF signaling is poorly understood. Here, we demonstrate that endogenous, endothelial cell-expressed TFPI-1 controls TF-mediated signaling through PARs. In endothelial cells transduced with TF to mimic exacerbated TF expression in vascular cells, TF-VIIa-Xa ternary complex-dependent activation of PAR1 remained intact when TF-mediated Xa generation was blocked with 2.5 to 5 nM recombinant TFPI-1 (rTFPI-1). Concordantly, inhibition of signaling in PAR1-expressing Chinese hamster ovary (CHO) cells required about 30-fold higher rTFPI-1 concentrations than necessary for anticoagulation. Studies with proteoglycan-deficient CHO cells document a crucial role of accessory receptors in supporting the anticoagulant and antisignaling activities of rTFPI-1. Coexpression of PAR2 with TF enhanced rTFPI-mediated inhibition of TF-VIIa-Xa–mediated PAR1 signaling, suggesting an unexpected role of PAR2 in the inhibitory control of TF signaling. These experiments are of potential significance for the limited therapeutic benefit of rTFPI-1 in systemic inflammation and recommend caution in using anticoagulant potency as a measure to predict how efficacious TF-directed inhibitors block cell signaling during initiation of coagulation.
The association of patient trust and self-care among patients with diabetes mellitus
Authors: Bonds Denise E , Camacho Fabian , Bell Ronny A , Duren-Winfield Vanessa T , Anderson Roger T , Goff David C
Published: November 2004

Background

Diabetes requires significant alterations to lifestyle and completion of self management tasks to obtain good control of disease. The objective of this study was to determine if patient trust is associated with reduced difficulty and hassles in altering lifestyle and completing self care tasks.

Methods

A cross-sectional telephone survey and medical record review was performed to measure patient trust and difficulty in completing diabetes tasks among 320 medically underserved patients attending diabetes programs in rural North Carolina, USA. Diabetes tasks were measured three ways: perceived hassles of diabetic care activities, difficulty in completing diabetes-related care activities, and a global assessment of overall ability to complete diabetes care activities. The association of patient trust with self-management was examined after controlling for patient demographics, physical functioning, mental health and co-morbidities.

Results

Level of patient trust was high (median 22, possible max 25). Higher trust levels were associated with lower levels of hassles (p = 0.006) and lower difficulty in completing care activities (p = 0.001). Patients with higher trust had better global assessments of overall ability to complete diabetes care activities (p < 0.0001).

Conclusion

Higher patient trust in physicians is associated with reduced difficulty in completing disease specific tasks by patients. Further studies are needed to determine the causal relationship of this association, the effect of trust on other outcomes, and the potential modifiability of trust
Molecular and epidemiologic analysis of a county-wide outbreak caused by Salmonella enterica subsp. enterica serovar Enteritidis traced to a bakery
Authors: Lu Po-Liang , Hwang In-Jane , Tung Ya-Lina , Hwang Shang-Jyh , Lin Chun-Lu , Siu LK
Published: November 2004

Background

An increase in the number of attendees due to acute gastroenteritis and fever was noted at one hospital emergency room in Taiwan over a seven-day period from July to August, 2001. Molecular and epidemiological surveys were performed to trace the possible source of infection.

Methods

An epidemiological investigation was undertaken to determine the cause of the outbreak. Stool and blood samples were collected according to standard protocols per Center for Disease Control, Taiwan. Typing of the Salmonella isolates from stool, blood, and food samples was performed with serotyping, antibiotypes, and pulsed field gel electrophoresis (PFGE) following XbaI restriction enzyme digestion.

Results

Comparison of the number of patients with and without acute gastroenteritis (506 and 4467, respectively) during the six weeks before the outbreak week revealed a significant increase in the number of patients during the outbreak week (162 and 942, respectively) (relative risk (RR): 1.44, 95% confidence interval (CI): 1.22–1.70, P value < 0.001). During the week of the outbreak, 34 of 162 patients with gastroenteritis were positive for Salmonella, and 28 of these 34 cases reported eating the same kind of bread. In total, 28 of 34 patients who ate this bread were positive for salmonella compared to only 6 of 128 people who did not eat this bread (RR: 17.6, 95%CI 7.9–39.0, P < 0.001). These breads were produced by the same bakery and were distributed to six different traditional Chinese markets., Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis) was isolated from the stool samples of 28 of 32 individuals and from a recalled bread sample. All S. Enteritidis isolates were of the same antibiogram. PFGE typing revealed that all except two of the clinical isolates and the bread isolates were of the same DNA macrorestriction pattern.

Conclusions

The egg-covered bread contaminated with S. Enteritidis was confirmed as the vehicle of infection. Alertness in the emergency room, surveillance by the microbiology laboratory, prompt and thorough investigation to trace the source of outbreaks, and institution of appropriate control measures provide effective control of community outbreaks.
Females do not have more injury road accidents on Friday the 13th
Authors: Radun Igor , Summala Heikki
Published: November 2004

Background

This study reinvestigated the recent finding that females – but not males – die in traffic accidents on Friday the 13th more often than on other Fridays (Näyhä S: Traffic deaths and superstition on Friday the 13th. Am J Psychiatry 2002, 159: 2110–2111). The current study used matched setting and injury accident data base that is more numerous than fatality data. If such an effect would be caused by impaired psychic and psychomotor functioning due to more frequent anxiety among women, it should also appear in injury crashes.

Methods

We used the national Finnish road accident database for 1989–2002. To control seasonal variation, 21 Fridays the 13th were compared in a matched design to previous and following Fridays, excluding all holidays, on number of accidents, male/female responsibility for accidents, and the number of dead, injured and overall number of active participants (drivers, pedestrians and bicyclists) as a consequence of the accident.

Results

There were no significant differences in any examined aspect of road injury accidents among the three Fridays, either in females or males. Women were not overrepresented in crashes that occurred on Fridays 13th.

Conclusion

There is no consistent evidence for females having more road traffic crashes on Fridays the 13th, based on deaths or road accident statistics. However, this does not imply a non-existent effect of superstition related anxiety on accident risk as no exposure-to-risk data are available. People who are anxious of "Black Friday" may stay home, or at least avoid driving a car.
Myasthenia gravis and pregnancy: clinical implications and neonatal outcome
Authors: Téllez-Zenteno José F , Hernández-Ronquillo Lizbeth , Salinas Vicente , Estanol Bruno , da Silva Orlando
Published: November 2004

Background

The myasthenia gravis is twice as common in women as in men and frequently affects young women in the second and third decades of life, overlapping with the childbearing years. Generally, during pregnancy in one third of patients the disease exacerbates, whereas in two thirds it remains clinically unchanged. Complete remission can occur in some patients.

Methods

To describe the clinical course, delivery and neonatal outcome of 18 pregnant women with the diagnosis of myasthenia gravis. Retrospective chart review of pregnant patients with myasthenia gravis, followed at the National Institute of Perinatology in Mexico City over an 8-year period. Data was abstracted from the medical records on the clinical course during pregnancy, delivery and neonatal outcome.

Results

From January 1, 1996 to December 31, 2003 18 patients with myasthenia gravis were identified and included in the study. The mean ± SD maternal age was 27.4 ± 4.0 years. During pregnancy 2 women (11%) had an improvement in the clinical symptoms of myasthenia gravis, 7 women (39%) had clinical worsening of the condition of 9 other patients (50%) remained clinically unchanged. Nine patients delivered vaginally, 8 delivered by cesarean section and 1 pregnancy ended in fetal loss. Seventeen infants were born at mean ± SD gestational age of 37.5 ± 3.0 weeks and a mean birth weight of 2710 ± 73 g. Only one infant presented with transient neonatal myasthenia gravis. No congenital anomalies were identified in any of the newborns.

Conclusions

The clinical course of myasthenia gravis during pregnancy is variable, with a significant proportion of patients experiencing worsening of the clinical symptoms. However, neonatal transient myasthenia was uncommon in our patient population.
Treatment decision-making and the form of risk communication: results of a factorial survey
Authors: Hembroff Larry A , Holmes-Rovner Margaret , Wills Celia E
Published: November 2004

Background

Prospective users of preventive therapies often must evaluate complex information about therapeutic risks and benefits. The purpose of this study was to evaluate the effect of relative and absolute risk information on patient decision-making in scenarios typical of health information for patients.

Methods

Factorial experiments within a telephone survey of the Michigan adult, non-institutionalized, English-speaking population. Average interview lasted 23 minutes. Subjects and sample design: 952 randomly selected adults within a random-digit dial sample of Michigan households. Completion rate was 54.3%.

Results

When presented hypothetical information regarding additional risks of breast cancer from a medication to prevent a bone disease, respondents reduced their willingness to recommend a female friend take the medication compared to the baseline rate (66.8% = yes). The decrease was significantly greater with relative risk information. Additional benefit information regarding preventing heart disease from the medication increased willingness to recommend the medication to a female friend relative to the baseline scenario, but did not differ between absolute and relative risk formats. When information about both increased risk of breast cancer and reduced risk of heart disease were provided, typical respondents appeared to make rational decisions consistent with Expected Utility Theory, but the information presentation format affected choices. Those 11% – 33% making decisions contrary to the medical indications were more likely to be Hispanic, older, more educated, smokers, and to have children in the home.

Conclusions

In scenarios typical of health risk information, relative risk information led respondents to make non-normative decisions that were "corrected" when the frame used absolute risk information. This population sample made generally rational decisions when presented with absolute risk information, even in the context of a telephone interview requiring remembering rates given. The lack of effect of gender and race suggests that a standard strategy of presenting absolute risk information may improve patient decision-making.
Spider silks: recombinant synthesis, assembly, spinning, and engineering of synthetic proteins
Authors: Scheibel Thomas
Published: November 2004

Since thousands of years humans have utilized insect silks for their own benefit and comfort. The most famous example is the use of reeled silkworm silk from Bombyx mori to produce textiles. In contrast, despite the more promising properties of their silk, spiders have not been domesticated for large-scale or even industrial applications, since farming the spiders is not commercially viable due to their highly territorial and cannibalistic nature. Before spider silks can be copied or mimicked, not only the sequence of the underlying proteins but also their functions have to be resolved. Several attempts to recombinantly produce spider silks or spider silk mimics in various expression hosts have been reported previously. A new protein engineering approach, which combines synthetic repetitive silk sequences with authentic silk domains, reveals proteins that closely resemble silk proteins and that can be produced at high yields, which provides a basis for cost-efficient large scale production of spider silk-like proteins.
Cyclic Adenosine 3′,5′-Monophosphate (cAMP) Enhances cAMP-Responsive Element Binding (CREB) Protein Phosphorylation and Phospho-CREB Interaction with the Mouse Steroidogenic Acute Regulatory Protein Gene Promoter
Authors: Clem Brian F. , Hudson Elizabeth A. , Clark Barbara J.
Published: November 2004

Steroidogenic acute regulatory protein (StAR) transcription is regulated through cAMP-protein kinase A-dependent mechanisms that involve multiple transcription factors including the cAMP-responsive element binding protein (CREB) family members. Classically, binding of phosphorylated CREB to cis-acting cAMP-responsive elements (5′-TGACGTCA-3′) within target gene promoters leads to recruitment of the coactivator CREB binding protein (CBP). Herein we examined the extent of CREB family member phosphorylation on protein-DNA interactions and CBP recruitment with the StAR promoter. Immunoblot analysis revealed that CREB, cAMP-responsive element modulator (CREM), and activating transcription factor (ATF)-1 are expressed in MA-10 mouse Leydig tumor cells, yet only CREB and ATF-1 are phosphorylated. (Bu)2cAMP treatment of MA-10 cells increased CREB phosphorylation approximately 2.3-fold within 30 min but did not change total nuclear CREB expression levels. Using DNA-affinity chromatography, we now show that CREB and ATF-1, but not CREM, interact with the StAR promoter, and this interaction is dependent on the activator protein-1 (AP-1) cis-acting element within the cAMP-responsive region. In addition, (Bu)2cAMP-treatment increased phosphorylated CREB (P-CREB) association with the StAR promoter but did not influence total CREB interaction. In vivo chromatin immunoprecipitation assays demonstrated CREB binding to the StAR proximal promoter is independent of (Bu)2cAMP-treatment, confirming our in vitro analysis. However, (Bu)2cAMP-treatment increased P-CREB and CBP interaction with the StAR promoter, demonstrating for the first time the physical role of P-CREB:DNA interactions in CBP recruitment to the StAR proximal promoter.
Overexpression of Gly56/Gly80/Gly81-Mutant Insulin-Like Growth Factor-Binding Protein-3 in Transgenic Mice
Authors: Silha Josef V. , Gui Yaoting , Mishra Suresh , Leckstrom Arnold , Cohen Pinchas , Murphy Liam J.
Published: November 2004

IGF-independent effects of IGF-binding protein-3 (IGFBP-3) have been demonstrated in vitro; however, the physiological significance of these effects in vivo is unclear. We generated two transgenic (Tg) mouse strains that overexpress a human Gly56/Gly80/Gly81-mutant IGFBP-3 cDNA. This mutant has a markedly reduced affinity for the IGFs, but retains the IGF-independent effects. Serum levels of mutant IGFBP-3 were 156 ± 12 and 400 ± 24 ng/ml in hemizygous mice of strains 5005 and 5012, respectively. When Tg and wild-type mice were compared, there was no reduction in birth weight, litter size, or postnatal growth. Despite differences in transgene expression in various tissues, relative organ weight was similar in Tg and wild-type mice, with exception of brain, where a modest reduction in brain weight was observed in the high-expressing 5012 lineage. There was also a significant reduction in proliferating cell nuclear antigen-staining cells observed in the periventricular region of the developing brain in embryonic d 18 Tg embryos. In the higher expressing 5012 Tg strain, IGF-I and murine IGFBP-3 levels, marker of GH action were increased. Furthermore, there was a positive correlation between mutant IGFBP-3 levels and IGF-I levels and between mutant IGFBP-3 levels and murine IGFBP-3 (P = 0.002 and P < 0.001, respectively). These data indicate that overexpression of mutant IGFBP-3 is not associated with growth retardation. The higher levels of IGF-I and murine IGFBP-3 in the 5012 Tg strain suggest that the growth inhibitory effect of mutant IGFBP-3 may be compensated for by other mechanisms.
Thyroid Hormone-Dependent Gene Expression in Differentiated Embryonic Stem Cells and Embryonal Carcinoma Cells: Identification of Novel Thyroid Hormone Target Genes by Deoxyribonucleic Acid Microarray Analysis
Authors: Liu Yan-Yun , Brent Gregory A.
Published: November 2004

T3 is required for normal early development, but relatively few T3-responsive target genes have been identified. In general, in vitro stem cell differentiation techniques stimulate a wide range of developmental programs, including thyroid hormone receptor (TR) pathways. We developed several in vitro stem cell models to more specifically identify TR-mediated gene expression in early development. We found that embryonic carcinoma (EC) cells have reduced T3 nuclear binding capacity and only modestly express the known T3 target genes, neurogranin (RC3) and Ca2+/calmodulin-dependent protein kinase IV (CaMKIV), in response to T3. Full T3 induction in transient transfection of EC cells was restored with cotransfection of a TR expression vector. We, therefore, performed gene expression profiles in wild-type embryonic stem (ES) cells compared with expression in cells with deficient (EC) or mutant TR (TRα P398H mutant ES cells), to identify T3 target genes. T3 stimulation of wild-type ES cells altered mRNA expression of 610 known genes (26% of those studied), although only approximately 60 genes (1%) met criteria for direct T3 stimulation based on the magnitude of induction and requirement for the presence of TR. We selected five candidate T3 target genes, neurexophilin 2, spermatid perinuclear RNA-binding protein (SPNR), kallikrein-binding protein (KBP), prostate-specific membrane antigen (PSMA), and synaptotagmin II, for more detailed study. T3 responsiveness of these genes was evaluated in both in vitro endogenous gene expression and in vivo mouse model systems. These genes identified in a novel stem cell system, including those induced and repressed in response to T3, may mediate thyroid hormone actions in early development.
Overexpression of an N-Terminally Truncated Isoform of the Nuclear Receptor Coactivator Amplified in Breast Cancer 1 Leads to Altered Proliferation of Mammary Epithelial Cells in Transgenic Mice
Authors: Tilli Maddalena T. , Reiter Ronald , Oh Annabell S. , Henke Ralf T. , McDonnell Kevin , Gallicano G. Ian , Furth Priscilla A. , Riegel Anna Tate
Published: November 2004

Amplified in breast cancer 1 (AIB1, also known as ACTR, SRC-3, RAC-3, TRAM-1, p/CIP) is a member of the p160 nuclear receptor coactivator family involved in transcriptional regulation of genes activated through steroid receptors, such as estrogen receptor α (ERα). The AIB1 gene and a more active N-terminally deleted isoform (AIB1-Δ3) are overexpressed in breast cancer. To determine the role of AIB1-Δ3 in breast cancer pathogenesis, we generated transgenic mice with human cytomegalovirus immediate early gene 1 (hCMVIE1) promoter-driven over-expression of human AIB1/ACTR-Δ3 (CMVAIB1/ACTR-Δ3 mice). AIB1/ACTR-Δ3 transgene mRNA expression was confirmed in CMV-AIB1/ACTR-Δ3 mammary glands by in situ hybridization. These mice demonstrated significantly increased mammary epithelial cell proliferation (P < 0.003), cyclin D1 expression (P = 0.002), IGF-I receptor protein expression (P = 0.026), mammary gland mass (P < 0.05), and altered expression of CCAAT/enhancer binding protein isoforms (P = 0.029). At 13 months of age, mammary ductal ectasia was found in CMV-AIB1/ACTR-Δ3 mice, but secondary and tertiary branching patterns were normal. There were no changes in the expression patterns of either ERα or Stat5a, a downstream mediator of prolactin signaling. Serum IGF-I levels were not altered in the transgenic mice. These data indicate that overexpression of the AIB1/ACTR-Δ3 isoform resulted in altered mammary epithelial cell growth. The observed changes in cell proliferation and gene expression are consistent with alterations in growth factor signaling that are thought to contribute to either initiation or progression of breast cancer. These results are consistent with the hypothesis that the N-terminally deleted isoform of AIB1 can play a role in breast cancer development and/or progression.
Adenosinergic and cholinergic control mechanisms during hypoxia in the epaulette shark (Hemiscyllium ocellatum), with emphasis on branchial circulation
Authors: Stensløkken Kåre-Olav , Sundin Lena , Renshaw Gillian M. C. , Nilsson Göran E.
Published: November 2004

Coral reef platforms may become hypoxic at night during low tide. One animal in that habitat, the epaulette shark (Hemiscyllium ocellatum),survives hours of severe hypoxia and at least one hour of anoxia. Here, we examine the branchial effects of severe hypoxia (<0.3 mg oxygen l–1 for 20 min in anaesthetized epaulette shark), by measuring ventral and dorsal aortic blood pressure (PVAand PDA), heart rate (fh), and observing gill microcirculation using epi-illumination microscopy. Hypoxia induced a flow of blood in two parallel blood vessels, termed longitudinal vessels, in the outer borders of the free tip of the gill filament. Hypoxia also induced significant falls in fh, PVA and PDA, and a biphasic change in ventilation frequency (increase followed by decrease). Adenosine injection (1μmol kg–1) also initiated blood flow in the longitudinal vessels, in addition to significant drops in PVA, PDA and fh, and a biphasic response in ventilation frequency (decrease followed by increase) indicating that adenosine influences ventilation. Aminophylline (10 mg kg–1),an A1 and A2 adenosine receptor antagonist, blocked the effects of adenosine injection, and also significantly reduced blood flow in the longitudinal vessels during hypoxia. In the second part of the study, we examined the cholinergic influence on the cardiovascular circulation during severe hypoxia (<0.3 mg l–1) using antagonists against muscarinic (atropine 2 mg kg–1) and nicotinic (tubocurarine 5 mg kg–1) receptors. Injection of acetylcholine (ACh; 1μmol kg–1) into the ventral aorta caused a marked fall in fh, a large increase in PVA, but small changes in PDA (suggesting increased Rgill). Atropine was able to inhibit the branchial vascular responses to ACh but not the hypoxic bradycardia, suggesting the presence of muscarinic receptors on the heart and gill vasculature, and that the hypoxia induced bradycardia is of non-cholinergic origin. The results suggest that adenosine mediates increases in the arterio–venous circulation in the gill during hypoxia. This may serve to increase blood supply to heart and gill tissue.
Bacterial lipopolysaccharide (LPS) modulates corticotropin-releasing hormone (CRH) content and release in the brain of juvenile and adult tilapia (Oreochromis mossambicus; Teleostei)
Authors: Pepels P. P. L. M. , Bonga S. E. Wendelaar , Balm P. H. M.
Published: November 2004

Although immune endocrine interactions in teleost fish have been shown to involve adrenocorticotropin hormone (ACTH) and cortisol, the involvement of corticotropin-releasing hormone (CRH) has not been demonstrated. The present study investigates whether treatment with bacterial endotoxin(lipopolysaccharide, LPS) modulates brain CRH contents or in vitroCRH release in tilapia (Oreochromis mossambicus). 10 days LPS(Escherichia coli) exposure of juvenile tilapia (4.5 weeks post hatch) via the ambient water increased brain CRH and α-MSH content,whereas cortisol contents were not increased. This indicates that the elevation of brain CRH levels were not secondary to activation of HPI-axis. Adult tilapia were treated for 6 days with LPS (intraperitoneally) and were sampled before and after 24 h of confinement. Overall LPS pre-treatment modified the reaction of tilapia to the additional stressor of 24 h confinement, as interactions between LPS treatment and confinement were observed at the level of the hypothalamus (diencephalic CRH content), the pituitary (CRH and α-MSH content) and in plasma glucose levels. In vitro, LPS pre-treatment abolished CRH release from telencephalic tissues induced by norepinephrine, one of the CRH secretagogues released during stress in vivo. This effect might be a mechanism of action through which LPS in vivo abolished the up-regulation of telencephalic CRH induced by confinement stress. Our results provide evidence that the role of CRH in immune–endocrine interactions is a phylogenetically old mechanism, and we here demonstrate that LPS molecules are able to locally modulate CRH release in the central nervous system.
Crater landscape: two-dimensional oxygen gradients in the circulatory system of the microcrustaceanDaphnia magna
Authors: Pirow R. , Bäumer C. , Paul R. J.
Published: November 2004

Oxygen transport processes in millimetre-sized animals can be very complex,because oxygen molecules do not exclusively follow the pathway predetermined by the circulating fluid but may also simultaneously move from the respiratory surfaces to the tissues along different paths by diffusion. The present study made use of the oxygen-sensitive phosphorescence probe Oxyphor R2 to analyze the internal oxygen pathway in the transparent microcrustacean Daphnia magna. Oxyphor R2 was injected into the circulatory system and the distribution of oxygen partial pressure (PO2)in the haemolymph was measured by phosphorescence lifetime imaging in the PO2 range 0–6 kPa (0–30% air saturation). There were substantial differences in the shape of the two-dimensional PO2 profiles depending on the concentration of haemoglobin (Hb) in the haemolymph. A steep global gradient,from posterior to anterior, occurred in animals with low concentrations of Hb(90–167 μmol l–1 haem). In contrast, animals with a five- to sixfold higher concentration of Hb showed flat internal PO2 gradients which, however, were only present under reduced ambient oxygen tensions(PO2amb=3–1 kPa), when Hb was maximally involved in oxygen transport. Under these conditions, the presence of Hb at high concentrations stabilized the unloading PO2 in the central body to 0.9–0.4 kPa. Independent of Hb concentration and body size, the loading PO2 was always 0.5 kPa below the PO2amb. From these PO2 profiles, it was possible (i) to follow the track of oxygen within the animal, and (ii) to visualize the shift from a diffusion-dominated to a convection-dominated transport as a result of increased Hb concentration.
Partial link between the seasonal acquisition of cold-tolerance and desiccation resistance in the goldenrod gall flyEurosta solidaginis(Diptera: Tephritidae)
Authors: Williams Jason B. , Ruehl Naomi C. , Lee Richard E.
Published: November 2004

Possible links between seasonal increases in cold-tolerance and desiccation resistance were examined in field-collected larvae of the goldenrod gall fly, Eurosta solidaginis. From 20 September to 30 October 2001, larvae exhibited a gradual increase in cold-tolerance culminating in 100% survival of freezing at –20°C for 24 h. The increase in cold-tolerance was probably due to a concomitant increase in cryoprotectants as measured by hemolymph osmolality (488–695 mOsmol kg–1). In contrast to the gradual increase in cold-tolerance, larvae exhibited two distinct phases of reduced rates of water loss. The first phase was an abrupt sixfold decrease to 0.57 μg mm–2 h–1 between 3 and 16 October. The first phase of reduced rates of water loss was not correlated with changes in cold-tolerance; nor was it correlated with hemolymph osmolality and body water content, which remained constant throughout the study. The reduction in rates of water loss during the first phase were probably the result of decreased respiratory water loss as the larvae entered diapause, and possibly reduced cuticular water loss as larvae increased the amount of their cuticular hydrocarbons. Interestingly, the first phase of reduced water loss was associated with, and may have been cued by, a reduction in the water potential of the gall tissues surrounding the larvae. The second phase was a more subtle fourfold reduction in rates of water loss occurring between 16 October and 11 December. In contrast to the first phase,the second phase of increased desiccation resistance correlated closely with increases in hemolymph osmolality (568–870 mOsmol kg–1). The correlation between seasonal increases in hemolymph osmolality and reduction in rates of water loss may represent a link between desiccation resistance and cold-tolerance in this species.