bluuebunny/crossref_metadata_2025 huggingface dataset:
Case-Based Modeling for Learning Management and Interpersonal Skills
Authors: Lyons Paul
Published: September 2007

This article offers an introduction to case-based modeling (CBM) and a demonstration of the efficacy of this instructional model. CBM is grounded primarily in the concepts and theory of experiential learning, augmented by concepts of script creation. Although it is labor intensive, the model is one that has value for instruction in various management and interpersonal skills. The CBM approach may be adapted for use in many different topics or business disciplines, in colleges or on the job, in which skill building and decision situations can be embedded in case material. A brief, empirical study of a workplace variation of CBM is offered to help establish the efficacy of the model.
Behavioral Assembly Required: Particularly for Quantitative Courses
Authors: Mazen Abdelmagid
Published: September 2007

This article integrates behavioral approaches into the teaching and learning of quantitative subjects with application to statistics. Focusing on the emotional component of learning, the article presents a system dynamic model that provides descriptive and prescriptive accounts of learners' anxiety. Metaphors and the metaphorizing process are suggested as a creative strategy to deal with quantitative anxiety and to achieve transformative learning. The article provides detailed illustration for implementing the process in the learning of three core statistical concepts—expected value, normal curve, and confidence interval—in addition to brief images for regression.
Ethics Education: Using Inductive Reasoning To Develop Individual, Group, Organizational, and Global Perspectives
Authors: Taft Susan H. , White Judith
Published: September 2007

Ethics education that prepares students to address ethical challenges at work is a multifaceted and long-term endeavor. In this article, the authors propose an inductive ethics pedagogy that begins the process of ethics education by grounding students in their own individual ethical principles. The approach centers on developing students' ethical self-knowledge in three ways: using an inductive method to aid students in learning ethics from a foundation of their own beliefs, distinguishing ethics from related concepts, and examining ethical conduct at four different levels of analysis—individual, group, organizational, and international perspectives. The authors define ethics and provide a model, new to the literature, that distinguishes ethics from related concepts, such as law, morality, or values. They include a discussion of ethical and cultural relativism and ethical absolutism relevant to the global context. This article is intended for the ethics educator in undergraduate and graduate business courses.
Jarheads, Girly Men, and the Pleasures of Violence
Authors: Pelias Ronald J.
Published: September 2007

This article explores the troublesome ways in which violence and pleasure become conflated for both hypermasculine and effeminate men. Using images from contemporary culture and incidents from the author's life, the article ponders how men might negotiate this unfortunate bind.
S.I.P. (School Induced Psychosis)
Authors: Davis Amira Millicent
Published: September 2007

By way of autoethnographic poetry, I reflect on my daughter's struggle to negotiate the tenuous space created by the effects of post-Brown desegregated schooling in a predominantly White district, high family expectations, and her own identity as an African American teenage female. The story of this recent family crisis is viewed through multiple lenses as an African American female, single parent, educator, and artist. It is situated within the domain of educational critical race theory and its intersections with gender and class. Critical race theories in education have provided avenues for marginal voices to be heard. Further research and writing should be aimed toward amplifying these muted voices.
Performing the Event of Understanding in Hermeneutic Conversations With Narrative Texts
Authors: Freeman Melissa
Published: September 2007

The purpose of this article is to understand and explore the transformational potential of engaging with narrative texts in the context of research interviewing. Drawing from the hermeneutic philosophies of Heidegger, Gadamer, and Ricoeur, the process of understanding is described and framed within a specific kind of dialogue with the world: the hermeneutical. What this kind of dialogue might look like in practice is explored using examples of participant responses to texts in the context of interviews on parental involvement. The implications for research are then discussed.
How Did We Get This Far Apart? Disengagement, Relational Dialectics, and Narrative Control
Authors: Herrmann Andrew F.
Published: September 2007

In this layered account, the author explores the disintegration of the relationship with his fiancé. Through the concept of relational dialectics, the author explores the multiplicity of tensions in the relationship and the patterns of communication and interaction through which they are displayed. These tensions include the dialectics of closeness—separateness, certainty— uncertainty, and openness—closedness. Similarly, the relationship is viewed through the concept of the chaos narrative and stands as a noncanonical exemplar for romantic relationships. Finally, as authors of our own life stories, the author questions the moral responsibilities we have toward each other, both in the living of our life stories and in the telling of them. The events in this narrative corresponded with the hurricane season of 2004, which serves as a backdrop to the story.
On the Social Relations of Research
Authors: Walby Kevin
Published: September 2007

Institutional ethnography (IE) is a method of inquiry that problematizes social relations at the local site of lived experience and examines how textual sequences coordinate consciousness and ruling relations. This article explicates some of the shortcomings of IE, so future institutional ethnographers can work with these. I offer a critical assessment of IE, focusing on its ontology of the social and the issue of truncation, the constitutive hermeneutics of interviewing, and the production of possible subjects in data analysis. The promise of IE is its critique of traditional sociology and introduction of ethnographic practice inquiring beyond nominalism into extra-local social relations that, through texts, govern local action. But IE establishes itself in a binary of emancipation versus regulation, so it is less concerned with its necessary complicity in objectification. IE must continue to be a sociology of possibilities, open to its own contradictions and continual reflexive intervention into itself.
Review: Multiple sclerosis and physical exercise: recommendations for the application of resistance-, endurance- and combined training
Authors: Dalgas U. , Stenager E. , Ingemann-Hansen T.
Published: September 2007

This review summarizes the existing knowledge regarding the effects of physical exercise in patients suffering from multiple sclerosis (MS). Furthermore, recommendations are given regarding exercise prescription for MS patients and for future study directions. Previously, MS patients were advised not to participate in physical exercise. During recent years, it has been increasingly acknowledged that exercise benefits MS patients. The requirement for exercise in MS patients is emphasized by their physiological profile, which probably reflects both the effects of the disease per se and the reversible effects of an inactive lifestyle. To date the effects of exercise have only been studied in moderately impaired MS patients with an EDSS score of less than 7. Evidence exists for recommending participation in endurance training at low to moderate intensity, as the existing literature demonstrates that MS patients can both tolerate and benefit from this training modality. Also, resistance training of moderate intensity seems to be well tolerated and to have beneficial effects on MS patients, but the methodological quality of the existing evidence is in general low and the number of studies is limited. Only two studies have evaluated the effects of combined resistance- and endurance training, making solid conclusions regarding this training modality impossible. Multiple Sclerosis 2008; 14: 35—53. http://msj.sagepub.com
Longitudinal magnetic resonance spectroscopic imaging of primary progressive multiple sclerosis patients treated with glatiramer acetate: multicenter study
Authors: Sajja B.R. , Narayana P.A. , Wolinsky J.S. , Ahn C.W. , N/A the PROMiSe Trial MRSI Group
Published: September 2007

Multicenter proton magnetic resonance spectroscopic imaging (MRSI) studies were performed on 58 primary progressive multiple sclerosis (PPMS) patients from four centers for investigating the efficacy of glatiramer acetate (GA) treatment. These patients were drawn from 943 subjects who participated in the PROMiSe trial. In these MRSI studies, patients were followed over a period of 3 years. MRSI data were acquired by all the centers using the same pulse sequence, and spectral analysis was performed at a single site using a customized analysis software package. Quantitative metabolite ratios, N-acetyl aspartate (NAA)/creatine (Cr) and choline (Cho)/Cr, were compared between GA-treated and placebo-treated PPMS patients. There was no significant difference in metabolite ratios between GA-treated and placebo-treated patients. The difference in metabolite ratios between the normal-appearing tissues (NAT) and lesion-containing regions (LCR) in GA treated patients was not significantly different from placebo treated patients. Strong lipid resonances, even in the absence of lesions, were observed on MRSI data in both gray matter and white matter in placebo- and GA-treated PPMS patients. No significant difference in number of patients with lipids between the two groups over a period of 3 years was found. Multiple Sclerosis 2008; 14: 73—80. http://msj.sagepub.com
Effect of exercise training on quality of life in multiple sclerosis: a meta-analysis
Authors: Motl R.W. , Gosney J.L.
Published: September 2007

Using meta-analytic procedures, this study examined the overall effect of exercise training interventions on quality of life (QOL) among individuals with multiple sclerosis (MS). We searched MEDLINE, PSYCHINFO and CURRENT CONTENTS PLUS for the period of 1960 to November 2006 using the key words exercise, physical activity and physical fitness in conjunction with QOL and MS. We further conducted a manual search of bibliographies of the retrieved papers as well as literature reviews and contacted study authors about additional studies. Twenty-five journal articles were located and reviewed, and only 13 provided enough data to compute effect sizes expressed as Cohen's d. One hundred and nine effect sizes were retrieved from the 13 studies with 484 MS participants and yielded a weighted mean effect size of g = 0.23 (95% CI = 0.15, 0.31). There were larger effects associated with MS-specific measures of QOL and fatigue as an index of QOL. The nature of the exercise stimulus further influenced the magnitude of the mean effect size. The cumulative evidence supports that exercise training is associated with a small improvement in QOL among individuals with MS. Multiple Sclerosis 2008; 14: 129—135. http://msj.sagepub.com
Reversion of immune tolerance in advanced malignancy: modulation of myeloid-derived suppressor cell development by blockade of stem-cell factor function
Authors: Pan Ping-Ying , Wang George X. , Yin Bingjiao , Ozao Junko , Ku Teresa , Divino Celia M. , Chen Shu-Hsia
Published: September 2007

Tumor growth induced a significant increase of myeloid-derived suppressor cells (MDSCs) in the tumor-bearing host. In our previous study, we showed that MDSCs induced tumor-specific T-cell tolerance and the development of T regulatory cells (Tregs). Tumor-derived factors have been implicated in the accumulation of MDSCs. We hypothesize that reduction of MDSC accumulation in tumor-bearing hosts, through the blockade of tumor factors, can prevent T-cell anergy and Treg development and thereby improve immune therapy for the treatment of advanced tumors. Several tumor-derived factors were identified by gene array analysis. Among the candidate factors, stem- cell factor (SCF) is expressed by various human and murine carcinomas and was selected for further study. Mice bearing tumor cells with SCF siRNA knockdown exhibited significantly reduced MDSC expansion and restored proliferative responses of tumor-infiltrating T cells. More importantly, blockade of SCF receptor (ckit)–SCF interaction by anti-ckit prevented tumor-specific T-cell anergy, Treg development, and tumor angiogenesis. Furthermore, the prevention of MDSC accumulation in conjunction with immune activation therapy showed synergistic therapeutic effect when treating mice bearing large tumors. This information supports the notion that modulation of MDSC development may be required to achieve effective immune-enhancing therapy for the treatment of advanced tumors.
Histone acetylation at the human β-globin locus changes with developmental age
Authors: Yin Wenxuan , Barkess Gráinne , Fang Xiangdong , Xiang Ping , Cao Hua , Stamatoyannopoulos George , Li Qiliang
Published: September 2007

To delineate the relationship between epigenetic modifications and hemoglobin switching, we compared the pattern of histone acetylation and pol II binding across the β-globin locus at fetal and adult stages of human development. To make this comparison possible, we introduced an external control into experimental samples in chromatin immunoprecipitation (ChIP) assays. Using this common standard, we found that the locus control region (LCR) was acetylated to the same level at all stages, whereas acetylation levels at the individual gene regions correlated with the state of transcription. In the active genes, the promoters were less acetylated compared with the coding regions. Furthermore, all globin promoters were acetylated to a similar level irrespective of the state of transcription. However, after correction for the loss of nucleosomes, the level of acetylation per histone at the active γ and β promoters was 5- to 7-fold greater than that at the inactive ε promoter. Although the histone acetylation level within the LCR was developmentally stable, pol II binding in fetal erythroblasts was 2- to 3-fold greater than that in adult erythroblasts. These results demonstrate that dynamic changes in histone acetylation and pol II take place as the human β-globin gene region undergoes its developmental switches.
Gene expression profiling reveals effects of Cimicifuga racemosa (L.) NUTT. (black cohosh) on the estrogen receptor positive human breast cancer cell line MCF-7
Authors: Gaube Friedemann , Wolfl Stefan , Pusch Larissa , Kroll Torsten C , Hamburger Matthias
Published: September 2007

Background

Extracts from the rhizome of Cimicifuga racemosa (black cohosh) are increasingly popular as herbal alternative to hormone replacement therapy (HRT) for the alleviation of postmenopausal disorders. However, the molecular mode of action and the active principles are presently not clear. Previously published data have been largely contradictory. We, therefore, investigated the effects of a lipophilic black cohosh rhizome extract and cycloartane-type triterpenoids on the estrogen receptor positive human breast cancer cell line MCF-7.

Results

Both extract and purified compounds clearly inhibited cellular proliferation. Gene expression profiling with the extract allowed us to identify 431 regulated genes with high significance. The extract induced expression pattern differed from those of 17β-estradiol or the estrogen receptor antagonist tamoxifen. We observed a significant enrichment of genes in an anti-proliferative and apoptosis-sensitizing manner, as well as an increase of mRNAs coding for gene products involved in several stress response pathways. These functional groups were highly overrepresented among all regulated genes. Also several transcripts coding for oxidoreductases were induced, as for example the cytochrome P450 family members 1A1 and 1B1. In addition, some transcripts associated with antitumor but also tumor-promoting activity were regulated. Real-Time RT-PCR analysis of 13 selected genes was conducted after treatment with purified compounds – the cycloartane-type triterpene glycoside actein and triterpene aglycons – showing similar expression levels compared to the extract.

Conclusion

No estrogenic but antiproliferative and proapoptotic gene expression was shown for black cohosh in MCF-7 cells at the transcriptional level. The effects may be results of the activation of different pathways. The cycloartane glycosides and – for the first time – their aglycons could be identified as an active principle in black cohosh.
Proto-oncogene HER-2 in normal, dysplastic and tumorous feline mammary glands: an immunohistochemical and chromogenic in situ hybridization study
Authors: Ordás Javier , Millán Yolanda , Dios Rafaela , Reymundo Carlos , Martín de las Mulas Juana
Published: September 2007

Background

Feline mammary carcinoma has been proposed as a natural model of highly aggressive, hormone-independent human breast cancer. To further explore the utility of the model by adding new similarities between the two diseases, we have analyzed the oncogene HER-2 status at both the protein and the gene levels.

Methods

Formalin-fixed, paraffin-embedded tissue samples from 30 invasive carcinomas, 7 benign lesions and two normal mammary glands were analyzed. Tumour features with prognostic value were recorded. The expression of protein HER-2 was analyzed by immunohistochemistry and the number of gene copies by means of DNA chromogenicin situhybridization.

Results

Immunohistochemical HER-2 protein overexpression was found in 40% of feline mammary carcinomas, a percentage higher to that observed in human breast carcinoma. As in women, feline tumours with HER-2 protein overexpression had pathological features of high malignancy. However, amplification of HER-2 was detected in 16% of carcinomas with protein overexpression, a percentage much lower than that observed in their human counterpart.

Conclusion

Feline mammary carcinoma would be a suitable natural model of that subset of human breast carcinomas with HER-2 protein overexpression without gene amplification.
A hybrid microfluidic-vacuum device for direct interfacing with conventional cell culture methods
Authors: Chung Bong Geun , Park Jeong Won , Hu Jia Sheng , Huang Carlos , Monuki Edwin S , Jeon Noo Li
Published: September 2007

Background

Microfluidics is an enabling technology with a number of advantages over traditional tissue culture methods when precise control of cellular microenvironment is required. However, there are a number of practical and technical limitations that impede wider implementation in routine biomedical research. Specialized equipment and protocols required for fabrication and setting up microfluidic experiments present hurdles for routine use by most biology laboratories.

Results

We have developed and validated a novel microfluidic device that can directly interface with conventional tissue culture methods to generate and maintain controlled soluble environments in a Petri dish. It incorporates separate sets of fluidic channels and vacuum networks on a single device that allows reversible application of microfluidic gradients onto wet cell culture surfaces. Stable, precise concentration gradients of soluble factors were generated using simple microfluidic channels that were attached to a perfusion system. We successfully demonstrated real-time optical live/dead cell imaging of neural stem cells exposed to a hydrogen peroxide gradient and chemotaxis of metastatic breast cancer cells in a growth factor gradient.

Conclusion

This paper describes the design and application of a versatile microfluidic device that can directly interface with conventional cell culture methods. This platform provides a simple yet versatile tool for incorporating the advantages of a microfluidic approach to biological assays without changing established tissue culture protocols.
Low specificity of HIV-testing on sputum specimens kept at ambient temperatures for 4 to 7 days: a blinded comparison
Authors: Egwaga Saidi M , Chonde Timothy M , Matee Mecky I , Mfinanga Sayoki G , Ngowi Prosper E , Lwilla Fred , Cobelens Frank GJ
Published: September 2007

Background

HIV testing on sputum using the QraQuick HIV1/2® assay has high sensitivity and specificity, and holds promise for application in tuberculosis surveys. Its performance under conditions that may occur during surveys in resource-poor countries is however, unknown. We assessed, in a blinded comparison with HIV serum testing, the sensitivity and specificity of the OraQuick® assay for detecting HIV antibody in sputum specimens kept at ambient temperature for up to 7 days, with and without decontaminant.

Methods

Paired sputum and blood specimens from consecutively diagnosed smear-positive tuberculosis patients were tested with OraQuick® and 2 HIV-1/2 ELISA's. Sputum was tested within 24 hours of collection, split into 2 aliquots with and without addition of cetylpyridium chloride, and tested again after 4 and 7 days.

Results

Complete data was available for 377/435 (87%) enrolled patients; 132 (35%) tested HIV positive on serum. The sensitivity of the sputum test was 94.7% (95% CI 89.4–97.8) on day 1, 93.2% on day 4 and 92.9% on day 7. The specificity was 92.9% (95% CI 88.9–95.8) on day 1, and declined to 76.7% on day 4 (p < 0.001) and to 62.7% on day 7 (p < 0.001). Adding cetylpyridium chloride further decreased the specificity to 67.8% on day 4 (p = 0.04) and to 49.6% on day 7 (p = 0.004).

Conclusion

Transportation of sputum specimens at ambient temperatures for 4 days or more, and addition of decontaminant, strongly affect the specificity of the OraQuick® assay. Unless applied within one day, this assay is not suitable for estimation of HIV-prevalence among tuberculosis patients in survey settings.
Are physical symptoms among survivors of a disaster presented to the general practitioner? A comparison between self-reports and GP data
Authors: van den Berg Bellis , Yzermans C Joris , van der Velden Peter G , Stellato Rebecca K , Lebret Erik , Grievink Linda
Published: September 2007

Background

Most studies examining medically unexplained symptoms (MUS) have been performed in primary or secondary care and have examined symptoms for which patients sought medical attention. Disasters are often described as precipitating factors for MUS. However, health consequences of disasters are typically measured by means of questionnaires, and it is not known whether these self-reported physical symptoms are presented to the GP. It is also not known if the self-reported symptoms are related to a medical disorder or if they remain medically unexplained. In the present study, three research questions were addressed. Firstly, were self-reported symptoms among survivors presented to the GP? Secondly, were the symptoms presented to the GP associated with a high level of functional impairment and distress? Thirdly, what was the GP's clinical judgment of the presented symptoms, i.e. were the symptoms related to a medical diagnosis or could they be labeled MUS?

Methods

Survivors of a man-made disaster (N = 887) completed a questionnaire 3 weeks (T1) and 18 months (T2) post-disaster. This longitudinal health survey was combined with an ongoing surveillance program of health problems registered by GPs.

Results

The majority of self-reported symptoms was not presented to the GP and survivors were most likely to present persistent symptoms to the GP. For example, survivors with stomachache at both T1 and T2 were more likely to report stomachache to their GP (28%) than survivors with stomachache at only T1 (6%) or only T2 (13%). Presentation of individual symptoms to the GP was not consistently associated with functional impairment and distress. 56 – 91% of symptoms were labeled as MUS after clinical examination.

Conclusion

These results indicate that the majority of self-reported symptoms among survivors of a disaster are not presented to the GP and that the decision to consult with a GP for an individual symptom is not dependent on the level of impairment and distress. Also, self-reported physical symptoms such as headache, back pain and shortness of breath are likely to remain medically unexplained after the clinical judgment of a GP.
Health care utilisation under the 30-Baht Scheme among the urban poor in Mitrapap slum, Khon Kaen, Thailand: a cross-sectional study
Authors: Coronini-Cronberg Sophie , Laohasiriwong Wongsa , Gericke Christian A
Published: September 2007

Background

In 2001, the Government of Thailand introduced a universal coverage scheme with the aim of ensuring equitable health care access for even the poorest citizens. For a flat user fee of 30 Baht per consultation, or for free for those falling into exemption categories, every scheme participant may access registered health services. The exemption categories include children under 12 years of age, senior citizens aged 60 years and over, the very poor, and volunteer health workers. The functioning of these exemption mechanisms and the effect of the scheme on health service utilisation among the poor is controversial.

Methods

This cross-sectional study investigated the prevalence of 30-Baht Scheme registration and subsequent self-reported health service utilisation among an urban poor population in the Teparuk community within the Mitrapap slum in Khon Kaen city, northeastern Thailand. Furthermore, the effectiveness of the exemption mechanisms in reaching the very poor and the elderly was examined. Factors for users' choice of health facilities were identified.

Results

Overall, the proportion of the Teparuk community enrolled with the 30-Baht Scheme was high at 86%, with over one quarter of these exempted from paying the consultation fee. User fee exemption was significantly more frequent among households with an above-poverty-line income (64.7%) compared to those below the poverty line (35.3%), χ2 (df) = 5.251 (1); p-value = 0.018. In addition, one third of respondents over 60 years of age were found to be still paying user fees. Self-reported use of registered medical facilities in case of illness was stated to be predominantly due to the service being available through the scheme, with service quality not a chief consideration. Overall consumer satisfaction was high, especially among those not required to pay the 30 Baht user fee.

Conclusion

Whilst the 30-Baht Scheme seems to cover most of the poor population of Mitrapap slum in Khon Kaen, the user fee exemption mechanism only works partially with regard to reaching the poorest and exempting senior citizens. Service utilisation and satisfaction are highest amongst those who are fee-exempt. Service quality was not an important factor influencing choice of health facility. Ways should be sought to improve the effectiveness of the current exemption mechanisms.
Host predisposition by endogenous Transforming Growth Factor-β1 overexpression promotes pulmonary fibrosis following bleomycin injury
Authors: Haider Yussef , Malizia Andrea P , Keating Dominic T , Birch Mary , Tomlinson Annette , Martin Gail , Ferguson Mark WJ , Doran Peter P , Egan Jim J
Published: September 2007

Background

Idiopathic Pulmonary Fibrosis (IPF) is a progressive diffuse disease involving the lung parenchyma. Despite recent advances, the molecular mechanisms of the initiation and progression of this disease remain elusive. Previous studies have demonstrated TGFβ1 as a key effector cytokine in the development of lung fibrosis.

Methods

In this study we have used a transgenic mouse based strategy to identify the effect of overexpression of this key effector mediator on the development of pulmonary fibrosis in response to exogenous injury. We bred two lines (line 25 and 18) of transgenic mice (Tr+) that overexpressed active TGFβ1. Three-month old transgenic and wild type mice were subsequently wounded with intraperitoneal bleomycin. Mice were sacrificed at 6 weeks post-bleomycin and their lungs analysed histologically and biochemically.

Results

The severity of lung fibrosis was significantly greater in the Tr+ mice compared to the wild type mice. Using an oligonucleotide microarray based strategy we identified discrete patterns of gene expression contributing to TGFβ1 associated pulmonary fibrosis.

Conclusion

This data emphasises the importance of a host predisposition in the form of endogenous TGFβ1, in the development of pulmonary fibrosis in response to an exogenous injury.
Evaluation of a peer counselling programme to sustain breastfeeding practice in Hong Kong
Authors: Wong Esther HY , Nelson EAS , Choi Kai-Chow , Wong Kin-Ping , Ip Carmen , Ho Lau-Cheung
Published: September 2007

Background

Peer counselling is reported to increase breastfeeding rates. We evaluated an intervention consisting of mainly telephone contact peer counselling programme on breastfeeding duration and exclusivity.

Methods

Peer counsellors (PCs) were mothers who had successfully breastfed and had received formal training. Following a postnatal visit, they provided scheduled telephone consultations (Days 1, 4, 7, Weeks 2, 4, 8, and Month 4) to PC group mothers (n = 100) who continued breastfeeding their infants after discharge. Control group mothers (n = 100) received routine care.

Results

After adjusting for mothers' previous breastfeeding experiences, mothers' working status and breastfeeding problems, no statistical differences in mothers' feeding methods (exclusive, almost exclusive or predominant breastfeeding) were noted at the three follow-up times for intervention and control mothers respectively (Day 5: 37%/38%, 46%/53%, 57%/63%; Month 3: 10%/9%, 17%/23%, 20%/26%; Month 6: 2%/1%, 18%/18%, 18%/19%). All differences between the groups were not significant. Also, there was no evidence to suggest that PC intervention prolonged breastfeeding duration.

Conclusion

The lack of effect of our PC intervention may reflect the low baseline breastfeeding rate and low value placed on breastfeeding in our population, the type of PC intervention or group allocation biases.

Trial registration

ISRCTN93605280.
Determination of the threshold of cardiac troponin I associated with an adverse postoperative outcome after cardiac surgery: a comparative study between coronary artery bypass graft, valve surgery, and combined cardiac surgery
Authors: Fellahi Jean-Luc , Hedoire François , Le Manach Yannick , Monier Emmanuel , Guillou Louis , Riou Bruno
Published: September 2007

Introduction

The objective of the present study was to compare postoperative cardiac troponin I (cTnI) release and the thresholds of cTnI that predict adverse outcome after elective coronary artery bypass graft (CABG), after valve surgery, and after combined cardiac surgery.

Methods

Six hundred and seventy-five adult patients undergoing conventional cardiac surgery with cardiopulmonary bypass were retrospectively analyzed. Patients in the CABG (n = 225) and valve surgery groups (n = 225) were selected after matching (age, sex) with those in the combined surgery group (n = 225). cTnI was measured preoperatively and 24 hours after the end of surgery. The main endpoint was a severe postoperative cardiac event (sustained ventricular arrhythmias requiring treatment, need for inotropic support or intraaortic balloon pump for at least 24 hours, postoperative myocardial infarction) and/or death. Data are presented as the median and the odds ratio (95% confidence interval).

Results

Postoperative cTnI levels were significantly different among the three groups (combined surgery, 11.0 (9.5–13.1) ng/ml versus CABG, 5.2 (4.7–5.7) ng/ml and valve surgery, 7.8 (7.6–8.0) ng/ml; P < 0.05). The thresholds of cTnI predicting severe cardiac event and/or death were also significantly different among the three groups (combined surgery, 11.8 (11.5–14.8) ng/ml versus CABG, 7.8 (6.7–8.8) ng/ml and valve surgery, 9.3 (8.0–14.0) ng/ml; P < 0.05). An elevated cTnI above the threshold in each group was significantly associated with a severe cardiac event and/or death (odds ratio, 4.33 (2.82–6.64)).

Conclusion

The magnitude of postoperative cTnI release is related to the type of cardiac surgical procedure. Different thresholds of cTnI must be considered according to the procedure type to predict early an adverse postoperative outcome.
Androgenic Influences on Behavior, Body Weight, and Body Composition in a Model of Chronic Social Stress
Authors: Nguyen Mary M. N. , Tamashiro Kellie L. K. , Melhorn Susan J. , Ma Li Y. , Gardner Stacy R. , Sakai Randall R.
Published: September 2007

The visible burrow system (VBS) is a model used to study chronic social stress in colony-housed rats. A hierarchy develops among the males resulting in dominant (DOM) and subordinate (SUB) animals. Hierarchy-associated changes in body weight, body composition, behavior, and neuroendocrine measures have been observed. After 14 d of VBS housing, SUB animals have decreased body weight, elevated corticosterone, and decreased testosterone (T), compared with DOM animals and controls, placing SUB animals in an ideal endocrine state to regain lost body weight as adipose tissue. It is hypothesized that maintaining constant androgen concentrations in SUB males during stress will prevent body weight loss by maintaining more lean body mass. To test this, animals were gonadectomized and implanted with SILASTIC implants containing T, 5α-dihydrotestosterone (DHT), or cholesterol. Implants maintained constant physiological levels of T. Standard intact, T, and DHT implant colonies formed hierarchies, whereas cholesterol colonies did not. Androgen manipulations significantly altered offensive and defensive behaviors only on the first day of VBS housing. After VBS stress, intact, T, and DHT SUB animals weighed less and lost more adipose and lean tissue than DOM and control males, whereas DOM animals primarily lost adipose tissue. However, on recovery, DHT SUB animals maintained more lean tissue than intact SUB animals. Oral glucose tolerance tests revealed that glucose clears faster in stressed T-implanted males that have increased adipose tissue. Overall, these data suggest that constant androgen concentrations in SUB animals do not prevent weight loss and changes in body composition during stress but do so during recovery.
Fadrozole Reverses Cardiac Fibrosis in Spontaneously Hypertensive Heart Failure Rats: Discordant Enantioselectivity Versus Reduction of Plasma Aldosterone
Authors: Minnaard-Huiban Monica , Emmen Judith M. A. , Roumen Luc , Beugels Ilona P. E. , Cohuet Géraldine M. S. , van Essen Helma , Ruijters Eveline , Pieterse Koen , Hilbers Peter A. J. , Ottenheijm Harry C. J. , Plate Ralf , de Gooyer Marcel E. , Smits Jos F. M. , Hermans J. J. Rob
Published: September 2007

Reversal of cardiac fibrosis is a major determinant of the salutary effects of mineralocorticoid receptor antagonists in heart failure. Recently, R-fadrozole was coined as an aldosterone biosynthesis inhibitor, offering an appealing alternative to mineralocorticoid receptor antagonists to block aldosterone action. The present study aimed to evaluate the effects of R- and S-fadrozole on plasma aldosterone and urinary aldosterone excretion rate and to compare their effectiveness vs. the mineralocorticoid receptor antagonist potassium canrenoate to reverse established cardiac fibrosis. Male lean spontaneously hypertensive heart failure (SHHF) rats (40 wk) were treated for 8 wk by sc infusions of low (0.24 mg/kg·d) or high (1.2 mg/kg·d) doses of R- or S-fadrozole or by potassium canrenoate via drinking water (7.5 mg/kg·d). At the high dose, plasma aldosterone levels were decreased similarly by R- and S-fadrozole, whereas urinary aldosterone excretion rate was reduced only by S-fadrozole. In contrast, whereas at the high dose, R-fadrozole effectively reversed preexistent left ventricular interstitial fibrosis by 50% (vs. 42% for canrenoate), S-fadrozole was devoid of an antifibrotic effect. The low doses of the fadrozole enantiomers did not change cardiac fibrosis or plasma aldosterone but similarly reduced urinary aldosterone excretion rate. In conclusion, R-fadrozole may possess considerable therapeutic merit because of its potent antifibrotic actions in the heart. However, the observed discordance between the aldosterone-lowering and antifibrotic effects of the fadrozole enantiomers raises some doubt about the mechanism by which R-fadrozole diminishes cardiac collagen and about the generality of the concept of lowering aldosterone levels to treat the diseased heart.
Meiotic Maturation of Incompetent Prepubertal Sheep Oocytes Is Induced by Paracrine Factor(s) Released by Gonadotropin-Stimulated Oocyte-Cumulus Cell Complexes and Involves Mitogen-Activated Protein Kinase Activation
Authors: Cecconi Sandra , Mauro Annunziata , Capacchietti Giulia , Berardinelli Paolo , Bernabò Nicola , Di Vincenzo Anna Rita , Mattioli Mauro , Barboni Barbara
Published: September 2007

In this study, sheep oocyte-cumulus cell complexes (OCC) derived from medium (M) antral follicles (M-OCC) were in vitro matured alone or in coculture with OCC derived from small (S) antral follicles (S-OCC) to investigate the contribution of cumulus cells (CC) and oocytes to the process of oocyte meiotic maturation and cumulus expansion (CE). Experiments were conducted with or without gonadotropins (FSH/LH). Regardless of culture conditions, about 12% of S-oocytes reached the metaphase II stage, and S-CC showed a low degree of CE. In contrast, both maturational processes were significantly stimulated by gonadotropins in M-OCC. However, about 48% of S-oocytes progressed to metaphase II, and S-CC expanded after coculture with gonadotropin-stimulated M-OCC and M-CC but not with mural granulosa cells. Both maturational processes were inhibited when S-OCC were cocultured with M-denuded oocytes, or when S-denuded oocytes were cocultured with M-CC. The capacity of these paracrine factor(s) to activate the MAPK pathway in somatic and germ cells of S-complexes was investigated. It was found that MAPK kinase/MAPK phosphorylation levels in M-OCC but not in S-OCC were significantly increased by gonadotropins, first in CC and later in the oocytes. Kinase phosphorylations were activated only in S-oocytes cocultured with M-OCC or M-CC. These results demonstrate that soluble factors specifically produced by M-CC are capable to induce meiotic maturation and CE in S-complexes by acting via CC. These factors can induce MAPK activation only in S-oocytes, whose meiotic arrest could be due to the inability of surrounding CC to respond to gonadotropin stimulation.
C. elegansorthologs of components of the RB tumor suppressor complex have distinct pro-apoptotic functions
Authors: Schertel Claus , Conradt Barbara
Published: September 2007

To obtain insight into the role of the retinoblastoma susceptibility gene(Rb; also known as Rb1) in apoptosis, we analyzed Caenorhabditis elegans mutants lacking a functional lin-35RB gene. We found that the loss of lin-35 function results in a decrease in constitutive germ cell apoptosis. We present evidence that lin-35 promotes germ cell apoptosis by repressing the expression of ced-9, an anti-apoptotic C. elegans gene that is orthologous to the human proto-oncogene BCL2. Furthermore, we show that the genes dpl-1 DP, efl-1 E2F and efl-2 E2F also promote constitutive germ cell apoptosis. However, in contrast to lin-35,dpl-1 (and probably also efl-1 and efl-2) promotes germ cell apoptosis by inducing the expression of the pro-apoptotic genes ced-4 and ced-3, which encode an APAF1-like adaptor protein and a pro-caspase, respectively. Based on these results, we propose that C. elegans orthologs of components of the RB tumor suppressor complex have distinct pro-apoptotic functions in the germ line and that the transcriptional regulation of components of the central apoptosis machinery is a critical determinant of constitutive germ cell apoptosis in C. elegans. Finally, we demonstrate that lin-35, dpl-1 and efl-2, but not efl-1, function either downstream of or in parallel to cep-1 p53 (also known as TP53) and egl-1BH3-only to cause DNA damage-induced germ cell apoptosis. Our results have implications for the general mechanisms through which RB-like proteins control gene expression, the role of RB-, DP- and E2F-like proteins in apoptosis, and the regulation of apoptosis.
FGF9 and SHH regulate mesenchymalVegfaexpression and development of the pulmonary capillary network
Authors: White Andrew C. , Lavine Kory J. , Ornitz David M.
Published: September 2007

The juxtaposition of a dense capillary network to lung epithelial cells is essential for air-blood gas exchange. Defective lung vascular development can result in bronchopulmonary dysplasia and alveolar capillary dysplasia. Although vascular endothelial growth factor A (Vegfa) is required for formation of the lung capillary network, little is known regarding the factors that regulate the density and location of the distal capillary plexus and the expression pattern of Vegfa. Here, we show that fibroblast growth factor 9 (FGF9) and sonic hedgehog (SHH) signaling to lung mesenchyme, but not to endothelial cells, are each necessary and together sufficient for distal capillary development. Furthermore, both gain- and loss-of-function of FGF9 regulates Vegfa expression in lung mesenchyme, and VEGF signaling is required for FGF9-mediated blood vessel formation. FGF9, however, can only partially rescue the reduction in capillary density found in the absence of SHH signaling, and SHH is unable to rescue the vascular phenotype found in Fgf9-/- lungs. Thus, both signaling systems regulate distinct aspects of vascular development in distal lung mesenchyme. These data suggest a molecular mechanism through which FGF9 and SHH signaling coordinately control the growth and patterning of the lung capillary plexus,and regulate the temporal and spatial expression of Vegfa.
The pattern of β-catenin responsiveness within the mammary gland is regulated by progesterone receptor
Authors: Hiremath Minoti , Lydon John P. , Cowin Pamela
Published: September 2007

Experiments involving β-catenin loss- and gain-of-function in the mammary gland have decisively demonstrated the role of this protein in normal alveologenesis. However, the relationship between hormonal and β-catenin signaling has not been investigated. In this study, we demonstrate that activated β-catenin rescues alveologenesis in progesterone receptor(PR; Pgr)-null mice during pregnancy. Two distinct subsets of mammary cells respond to expression of ΔN89β-catenin. Cells at ductal tips are inherently β-catenin-responsive and form alveoli in the absence of PR. However, PR activity confers β-catenin responsiveness to progenitor cells along the lateral ductal borders in the virgin gland. Once activated by β-catenin, responding cells switch on an alveolar differentiation program that is indistinguishable from that observed in pregnancy and is curtailed by PR signaling.
Phosphorylation of the atypical kinesin Costal2 by the kinase Fused induces the partial disassembly of the Smoothened-Fused-Costal2-Cubitus interruptus complex in Hedgehog signalling
Authors: Ruel Laurent , Gallet Armel , Raisin Sophie , Truchi Arnaud , Staccini-Lavenant Laurence , Cervantes Alexandra , Thérond Pascal P.
Published: September 2007

The Hedgehog (Hh) family of secreted proteins is involved both in developmental and tumorigenic processes. Although many members of this important pathway are known, the mechanism of Hh signal transduction is still poorly understood. In this study, we analyse the regulation of the kinesin-like protein Costal2 (Cos2) by Hh. We show that a residue on Cos2,serine 572 (Ser572), is necessary for normal transduction of the Hh signal from the transmembrane protein Smoothened (Smo) to the transcriptional mediator Cubitus interruptus (Ci). This residue is located in the serine/threonine kinase Fused (Fu)-binding domain and is phosphorylated as a consequence of Fu activation. Although Ser572 does not overlap with known Smo-or Ci-binding domains, the expression of a Cos2 variant mimicking constitutive phosphorylation and the use of a specific antibody to phosphorylated Ser572 showed a reduction in the association of phosphorylated Cos2 with Smo and Ci,both in vitro and in vivo. Moreover, Cos2 proteins with an Ala or Asp substitution of Ser572 were impaired in their regulation of Ci activity. We propose that, after activation of Smo, the Fu kinase induces a conformational change in Cos2 that allows the disassembly of the Smo-Fu-Cos2-Ci complex and consequent activation of Hh target genes. This study provides new insight into the mechanistic regulation of the protein complex that mediates Hh signalling and a unique antibody tool for directly monitoring Hh receptor activity in all activated cells.
Availability analysis of post-combustion carbon capture systems: Minimum work input
Authors: McGlashan N R , Marquis A J
Published: September 2007

This paper describes the availability analysis of a generic, post-combustion carbon capture plant. The analysis first establishes the minimum work input required in an ideal plant with a flue gas inlet temperature equal to the sink temperature. The analysis shows that the ideal work input is surprisingly low and that, roughly equal amounts of work are required to first separate and then compress the CO2 contained in a typical flue gas stream. The analysis is then extended to include the effects of variable inlet temperature and extraction efficiency. This extended analysis shows that there is a considerable quantity of available energy in the flue gas of a normal power station. Indeed, in principle, carbon capture is theoretically possible without any external work input for fuels of low carbon/hydrogen ratio such as heavy fuel oil and natural gas. When burning coal, the minimum work input would be significantly reduced if the flue gases' availability were utilized.

The final section of the paper compares the actual work input of a variety of carbon capture schemes found in the literature, with the minimum work input for an ideal process. This comparison shows that the techniques presently found in the literature have a low second-law efficiency.
Minimization of transmission errors in highly loaded plastic gear trains
Authors: Meuleman P Klein , Walton D , Dearn K D , Weale D J , Driessen I
Published: September 2007

Transmission errors (TEs) are an important source of unwanted noise and vibration in gear drives. Errors can result from geometrical inaccuracies and from elastic deformations. Plastic drives are often loaded in a way that produces high deflections relative to steel gears, and the elastic component of TE is relatively more important. Furthermore, plastic gears are often run in mesh with gears made from steel or other metals. In this case there is a large difference in tooth stiffness, which leads to unusual TE problems. The current paper discusses the origins of elastic TEs and means of their calculation. A simple beam model is used to demonstrate the stiffness of a pair of meshing gear teeth. A finite-element analysis is used to refine this model and to run iterative tooth meshing enabling TEs to be accurately characterized. A number of TE traces from gear pairs running under high loads are included and compared with the theoretical predictions. Several different scenarios are proposed including balancing gear tooth stiffness for dissimilar materials and the adjustment of pressure angle to account for tooth deflection. A set of design guidelines are presented in the conclusions. A case study of a precision printer drive is used to illustrate some of the techniques for the minimization of TEs.