bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Demand for Insurance With an Upper Limit on Coverage
Authors: Cummins J. David , Mahul Olivier 
Published: May 2004

AbstractThe demand for insurance is examined when the indemnity schedule is subject to an upper limit. The optimal contract is shown to display full insurance above a deductible up to the cap. Some results derived in the standard model with no upper limit on coverage turn out to be invalid; the optimal deductible of an actuarially fair policy is positive and insurance may be a normal good under decreasing absolute risk aversion. An increase in the upper limit would induce the policyholder with constant absolute risk aversion to reduce his or her optimal deductible and therefore this would increase the demand for insurance against small losses.
A Data‐Analytic Method for Forecasting Next Record Catastrophe Loss
Authors: Hsieh Ping‐Hung 
Published: May 2004

AbstractWe develop in this article a data‐analytic method to forecast the severity of next record insured loss to property caused by natural catastrophic events. The method requires and employs the knowledge of an expert and accounts for uncertainty in parameter estimation. Both considerations are essential for the task at hand because the available data are typically scarce in extreme value analysis. In addition, we consider three‐parameter Gamma priors for the parameter in the model and thus provide simple analytical solutions to several key elements of interest, such as the predictive moments of record value. As a result, the model enables practitioners to gain insights into the behavior of such predictive moments without concerning themselves with the computational issues that are often associated with a complex Bayesian analysis. A data set consisting of catastrophe losses occurring in the United States between 1990 and 1999 is analyzed, and the forecasts of next record loss are made under various prior assumptions. We demonstrate that the proposed method provides more reliable and theoretically sound forecasts, whereas the conditional mean approach, which does not account for either prior information or uncertainty in parameter estimation, may provide inadmissible forecasts.
Malassezia Enhances Natural Killer Cell‐Induced Dendritic Cell Maturation
Authors: Buentke E. , D'Amato M. , Scheynius A. 
Published: May 2004

AbstractHuman natural killer (NK) cells can induce cell death in autologous dendritic cells (DCs), though an interaction between these two cell types can also lead to a reciprocal activation. We have recently shown cell contact between NK cells and DCs in vivo, in Malassezia‐induced lesional skin of patients with atopic eczema, where the yeast acts as an allergen although it is part of the normal skin microflora. Here we characterize the interaction of human NK cells and monocyte‐derived DCs (MDDCs) by using an in vitro system where short‐term activated polyclonal NK cells are cocultured with autologous, immature, Malassezia‐stimulated or lipopolysaccharide‐matured MDDCs. We found that the number of CD83+ MDDCs increased in the immature and Malassezia‐stimulated MDDCs upon coculture with NK cells, while an increased number of CD86+ cells was detected in the Malassezia‐stimulated MDDCs. NK cell–MDDC interaction induced the production of interleukin‐8 (IL‐8). In conclusion, our results imply that NK cells provide maturation signals and may play a role in inducing IL‐8 production in DCs. Furthermore, the increased expression of CD86 on Malassezia‐stimulated MDDCs might have a function in subsequent T‐cell activation by DCs, and indicate a role for NK cell–DC interaction in modulating the immune responses to microbial stimuli.
Chicken B‐Cell‐Activating Factor: Regulator of B‐Cell Survival in the Bursa of Fabricius
Authors: Koskela K. , Nieminen P. , Kohonen P. , Salminen H. , Lassila O. 
Published: May 2004

AbstractPrevious studies on mammals have demonstrated that a tumour necrosis factor family member, B‐cell‐activating factor (BAFF) (BlyS, TALL‐1), is mainly produced by myeloid and dendritic cells and that BAFF promotes B‐cell differentiation and survival in a paracrine fashion. We have recently shown that BAFF is upregulated at the bursal stage of the avian B‐cell development. We now show that the avian bursal B cells and B‐cell lines, RP‐9, RP‐13 and DT40, express chicken BAFF (cBAFF). In situ hybridization confirms strong cBAFF expression within the bursal follicles. Like mammals, cBAFF is expressed in the avian myeloblast and myelomonocytic cell lines but not in the peripheral blood αβ and γδ T cells. The binding of recombinant human BAFF (hBAFF) to the bursal B‐cells indicates a conserved receptor–ligand binding. Furthermore, the recombinant hBAFF has a positive effect on bursal cell proliferation and transiently inhibits cell death in vitro. In conclusion, cBAFF is highly conserved structurally, but as a novel observation we suggest cBAFF to function in an autocrine fashion to promote the growth and maturation of follicular B cells in bursa of Fabricius.
Induction of a Mucosal Immune Response to the Streptococcal M Protein by Intramuscular Administration of a PADRE‐ASREAK Peptide
Authors: Pamonsinlapatham P. , Decroix N. , Mihaila‐Amrouche L. , Bouvet A. , Bouvet J.‐P. 
Published: May 2004

AbstractIn a previous study, it was shown that an intramuscular administration of amino acid PADRE‐ELDKWA sequence induced a mucosal immune response to a conserved epitope of human immunodeficiency virus in mice. In the same model, here it is shown that this method can be used with a selected peptide from the M protein of group A streptococci. The PADRE‐ASREAK sequence was injected in mice by the intramuscular route. Antibodies against M protein were detected in extracts of mucosal tissues and in serum. The repertoire isotypes of serum immunoglobulin G (IgG) and mucosal IgA and IgG antibodies varied, according to the dose of injected peptide. The highest mucosal IgA antibody response was obtained with 0.01 µg of antigen per injection, whereas the systemic IgG antibody response increased with 10 µg of antigen. Mucosal antibody production against streptococci was confirmed by immunofluorescence analysis. These results provide evidence that this novel approach of mucosal vaccination may be of advantage for bacterial systems and suggest a new field of investigation based on synthetic peptide analogues.
Alteration of an Autoantigen by Chlorination, a Process Occurring During Inflammation, Can Overcome Adaptive Immune Tolerance
Authors: Westman E. , Harris H. E. 
Published: May 2004

AbstractAutoimmune diseases are characterized by chronic inflammation in target organs and immunoreactivity towards one or multiple autoantigens. Several potential mechanisms of tolerance breaking have been postulated, one being inflammation‐associated events. We have investigated whether chlorination of an autoantigen can lead to disruption of self‐tolerance. Chlorination of antigens might occur during inflammation via the granulocyte‐specific, myeloperoxidase‐catalysed conversion of hydrogen peroxide to hypochlorous acid (HOCl). HOCl, being a strong oxidant, reacts with proteins both within cellular phagosomes and in the immediate extracellular environment. By immunizing Lew.1AV1 rats with chlorinated or unmodified rat serum albumin (RSA), we could detect tolerance‐breaking effects of chlorination. RSA is a systemic autoantigen in rat not inducing antibody production upon immunization in its unmodified form. Rats immunized with chlorinated RSA (RSA‐Cl) developed high titres of immunoglobulin G (IgG) specific for RSA‐Cl which cross‐reacted with native RSA. T cells reactive with both RSA‐Cl and RSA were detected by [3H]‐thymidine incorporation. We hence speculated that immunological tolerance established for unmodified proteins, during certain circumstances such as inflammation, might be broken by induced protein chlorination. T cells specific for the chlorinated protein can confer help to B cells recognizing both the chlorinated and the native form of the protein, leading to the formation of high‐affinity autoreactive antibodies and possibly autoimmune disease.
Expression of SPANX proteins in human‐ejaculated spermatozoa and sperm precursors
Authors: Salemi Michele , Calogero Aldo E. , Benedetto Daniela Di , Cosentino Anna , Barone Nunziata , Rappazzo Giancarlo , Vicari Enzo 
Published: May 2004

SummaryThe sperm protein associated with nucleus in the X chromosome (SPANX) gene family is constituted by only a few members, clustered at Xq27, encoding small proteins which range from 15 to 20 kDa. These proteins have been shown to be present both in mature spermatozoa and in tumours, such as melanoma and some leukaemias. We developed polyclonal sera in order to study the distribution of the protein in human‐ejaculated spermatozoa and their precursors. A synthetic peptide was designed from a domain common to the SPANX protein family and polyclonal sera were raised in mice. Seven healthy volunteer men with normal sperm parameters were recruited and the expression of SPANX proteins was evaluated in spermatozoa and ejaculated sperm precursors by immunocytochemistry and immunofluorescence analyses. SPANX proteins, present in a large fraction (96%) of mature spermatozoa, were localized in the sperm head (39.2%), midpiece (22.8%) or in both sites (34.4%). Spermatids also showed the presence of SPANX proteins in their cytoplasm, although a significantly higher number of spermatids were SPANX‐negative compared with spermatozoa. In conclusion, SPANX proteins are expressed in an elevated percentage of spermatids and mature spermatozoa. In the latter, they are preferentially located in the sperm head. The greater number of SPANX‐negative spermatids observed could relate to their easier exfoliation from the seminiferous tubules.
The neutral comet assay detects double strand DNA damage in selected and unselected human spermatozoa of normospermic donors
Authors: Van Kooij R. J. , De Boer P. , De Vreeden‐Elbertse J. M. T. , Ganga N. A. , Singh N. , Te Velde E. R. 
Published: May 2004

SummaryThe occurrence of DNA breaks in human sperm is of concern to genetic safety in artificial reproduction techniques. Here, we have explored the neutral comet assay (NCA) for evaluating the frequency of spermatozoa with double strand (ds) DNA breaks in normospermic donors. The NCA results into DNA tail formation by fibre extension and by the separation of DNA fragments. Gamma‐irradiated native, lysed and lysed plus RNA and protein degraded human sperm nuclei have been used to assess sensitivity and specificity of fragment formation as an indication for ds DNA breaks. At 5 and 10 Gy gamma irradiation, the sensitivity increases in the order: native, lysed, lysed plus RNA and protein degraded. At 10 Gy, a uniform response between donors was obtained. For technical and biological reasons, the NCA underestimates the true incidence of ds DNA breaks by an unknown factor. Semen samples of six healthy normospermic donors were differentiated by swim up and by Percoll density centrifugation, followed by the NCA. In native semen, percentages of sperm nuclei with ds DNA breaks ranged from 15 to 25%. Swim up and selection for high‐density sperm nuclei (high Percoll fraction) reduced the frequency of sperm with ds DNA breaks by about one third, whereas an increased frequency was found in the low Percoll fraction. In conclusion, the response to gamma irradiation of DNA fragment formation indicates the NCA to demonstrate ds DNA breaks which is in keeping with theory and experimental results from somatic cells. Ds DNA breaks are a characteristic of the sperm population of normal donors. Current sperm selection procedures reduce the fractions of sperm with ds DNA breaks, yet are not effective in eliminating these cells.
Cloning and characterization of a mouse spergen‐1 localized in sperm mitochondria
Authors: Matsuoka Yasuhiro , Iguchi Naoko , Kitamura Kouichi , Nishimura Hiromi , Manabe Hiroyuki , Miyagawa Yasushi , Koga Minoru , Matsumiya Kiyomi , Okuyama Akihiko , Tanaka Hiromitsu , Nishimune Yoshitake 
Published: May 2004

SummaryDevelopment of spermatozoa is a complex process involving specific morphological formation of flagella, nucleus and mitochondria. Although detailed morphological observations of these events are available, the molecular mechanisms remain to be fully elucidated. We report here the molecular cloning and characterization of mouse spergen‐1 encoding a sperm specific mitochondrial protein, from a haploid germ cell‐specific subtracted cDNA library of mouse testis. Isolated cDNA is c. 0.7 kb and contains a 465 bp ORF that encodes mouse spergen‐1, a sperm mitochondrial protein consisting of 154 predicted amino acids. Antibodies raised against mouse Spergen‐1 identified a testis‐specific c. 18 Mr × 103 band in Western blot analysis. The protein was localized to the mitochondria of mouse sperm. Comparison of the mouse and human genomic sequences showed that 55 bps of the 5′‐upstream region containing a CAAT box and binding sequence for NF‐κB is conserved and could be important for specific expression of mouse spergen‐1 in haploid germ cells.
Expression of the apoptosis inhibitor survivin in testicular tissue of infertile patients
Authors: Weikert Steffen , Schrader Mark , Müller Markus , Krause Hans , Miller Kurt 
Published: May 2004

SummaryApoptosis is a common phenomenon during spermatogenesis, and its dysregulation has been associated with male infertility. Survivin is an inhibitor of apoptosis protein that regulates apoptosis at cell division and is overexpressed in common human cancers. We investigated whether survivin mRNA expression is detectable in testicular biopsies from patients with infertility of varying aetiology. The aim of this study was to examine the testicular survivin expression in azoospermic men with normal spermatogenesis and in those with specific spermatogenic disorders. Survivin mRNA expression was detected by reverse transcriptase‐polymerase chain reaction in histologically classified testicular biopsy specimens from 30 azoospermic men. Survivin was found to be expressed in normal spermatogenesis (n = 10), in post‐meiotic spermatogenic arrest (n = 6), and in specimens showing a mixed picture of pre‐meiotic maturation arrest with sparse islands of post‐meiotic arrest (n = 2). In contrast, a lack of survivin expression was seen in specimens without haploid germ cells (pre‐meiotic maturation arrest, n = 2) and in those with Sertoli‐cell‐only syndrome (SCOS, n = 10). These data indicate for the first time that survivin is expressed in human testis. Moreover, its expression seems to correlate with the stage of maturation arrest in patients presenting with spermatogenic disorders. Survivin mRNA expression was not found in SCOS specimens, possibly indicating germ‐cell‐specific expression in human testicular tissue. Thus, survivin is a potential molecular marker of spermatogenesis, whose expression is altered in specific spermatogenic disorders.
Putative biological functions of the DAZ family
Authors: Yen Pauline H. 
Published: May 2004

SummaryThe Deleted in Azoospermia (DAZ) gene belongs to a gene family that consists of three members: BOULE, DAZ‐Like (DAZL) and DAZ. Members of the DAZ family are expressed exclusively in the germ cells, and their protein products contain a highly conserved RNA‐binding motif and a unique DAZ repeat. Null mutations of the DAZ family members affect the fertility of either male or female, or both sexes. DAZ and DAZL are expressed throughout most of the life of germ cells and are required for the development of primordial germ cells and the differentiation and maturation of the germ cells. BOULE is expressed around the time of meiosis and has a more limited function. The DAZ proteins bind to RNAs in vitro and in vivo and are probably involved in the post‐transcriptional regulation of mRNA expression. Their downstream RNA targets remain largely unknown, although members of the CDC25 gene family are potential candidates.
Chromosomal abnormalities in couples undergoing intracytoplasmic sperm injection. A study of 370 couples and review of the literature
Authors: Morel F. , Douet‐Guilbert N. , Le Bris M.‐J. , Amice V. , Le Martelot M. T. , Roche S. , Valéri A. , Derrien V. , Amice J. , De Braekeleer M. 
Published: May 2004

SummaryIntracytoplasmic sperm injection (ICSI) is now widely acknowledged as the most effective therapeutic approach to severe male infertility or unsuccessful in vitro fertilization. Cytogenetic investigations were performed in 370 females and 335 males prior to ICSI between January 1997 and April 2003. Nine men (2.7%) and 48 women (13%) had an abnormal karyotype, 44 females having some degree of numerical sex chromosome mosaicism. A review of the literature showed the prevalence of all types of chromosomal abnormalities to be much higher among male and female partners of couples examined prior to ICSI than among newborns. As most ICSIs are performed with ejaculated spermatozoa from oligospermic men, the distribution and the prevalence of the several types of chromosomal abnormalities are closer to those of oligospermic rather than azoospermic males. Our results combined with those of the literature stress the importance of karyotyping both male and female partners before ICSI is started. Adequate genetic counselling, possibly followed by prenatal diagnosis, should be offered if a chromosomal anomaly is detected.
Nursing ethics and conceptualizations of nursing: profession, practice and work
Authors: Liaschenko Joan , Peter Elizabeth 
Published: May 2004

Background. Nursing has been understood as a calling, vocation, profession, and most recently, a practice. Each of these conceptualizations has associated with it an ethics that has emphasized particular aspects of nursing reflecting the social position of nursing in a given historical period. The ethics associated with current understandings of nursing as a profession and a practice are, we believe, no longer adequate to address the social realities and moral challenges of health care work.Aim. The aim of this paper is to discuss the limitations of the ethics associated with profession and practice and to show why the concept of work can contribute to a nursing ethics.Discussion. The characteristics that have socially defined professionals, among them the possession of a unique body of knowledge, provision of an altruistic service to society, and autonomy in the sense of control over their work and work conditions, only partially reflect the realities of contemporary health care work. This is true even for physicians, an exemplar of a professional group. The ethics associated with the professions has tended to limit what counts as a moral concern and who is authorized to label them as such. More recently, the idea of a practice has been used to argue for an ethics in which professional activities of a certain kind and understood in a specific way are inherently moral. However, this approach is limited for similar reasons. Because morality cannot be separated from the social organization of health care, we argue that considering nursing primarily as work, in contrast to a profession or a practice, offers the possibility of an ethics that more completely reflects the complexity of contemporary health care.Conclusion. Beyond the obvious conclusion that nursing is work, conceptualizing nursing as work points to changing social realities that are raising significant ethical issues. As a concept, work inherently conveys value, connects intellectual and manual labour, and recognizes social divisions of labour. At the moment an ethics of work is merely an idea, but we believe that such an ethics would lead nurses to ask different questions and propose different answers to the moral challenges of the present and near future.
Occupational stress and constructive thinking: health and job satisfaction
Authors: Stacciarini Jeanne‐Marie R. , Tróccoli Bartholomeu Torres 
Published: May 2004

Background. Occupational stress is associated with specific situations, characteristics of the work environment, and individual perceptions and reactions in the context of the workplace, but many nursing studies of occupational stress have tended to analyse aspects related to the job itself. In Brazil nursing is acknowledged as a stressful occupation whose stresses are generally associated with the job itself, while the effects of personal characteristics on an individual's response to occupational stress are dismissed.Aims. The aim of this paper is to describe: (1) occupational stress, job satisfaction and state of health in Brazilian nurses, and (2) the relationship of these variables to a constructive thinking coping style.Methods. A correlational study was performed during 1999 with 461 nurses recruited from the public health and education system in the Federal District of Brazil. Instruments used were the Nursing Stress Inventory, Constructive Thinking Inventory, subscales of the Occupational Stress Indicator, and a researcher‐designed questionnaire.Results. Normal distributions were found for occupational stress, state of health (physical and psychological), and job satisfaction. Results suggest that nurses have fewer psychological health problems and similar job satisfaction compared with other Brazilian government white‐collar workers. Occupational stress was directly associated with state of health, and inversely associated with global constructive thinking and job satisfaction.Conclusions. Brazilian nurses in this study seem to have adapted satisfactorily to their profession, but the finding that constructive thinking was significantly related to psychological ill‐health, occupational stress and physical ill‐health highlights a need to value individual coping styles in the work environment.
The process of hospital discharge for medical patients: a model
Authors: Pearson Pauline , Procter Susan , Wilcockson Jane , Allgar Vicki 
Published: May 2004

Background.  The 1990 NHS Community Care Act established a requirement for hospital discharge policies and procedures in the United Kingdom to be developed in collaboration with local government authorities in order to ensure supported discharge for those in need.Aims.  The aim of the study reported in this paper was to track decisions about hospital discharge in relation to outcomes for a sample of medical patients and their carers, identified as at risk of experiencing unsuccessful discharge processes.Methods.  Themed unstructured interviews were conducted in three different hospitals with 30 patients identified as at risk of unsuccessful discharge and their carers pre‐ and postdischarge. Hospital, community and social care staff involved in the care of the patient were also interviewed.Findings.  Patients and carers were constantly negotiating their social roles, seeking to juggle appropriate identities and limited resources to maintain their own and each others’ dignity and quality of life. When the negotiation process was destabilized (for example, by exacerbation of chronic disease, withdrawal of some resource, or the experience of additional stressors – not necessarily health‐related), then either or both parties sought a way out. In all the cases examined the result was admission to hospital – usually, but not always, mediated by community professionals.Conclusions.  The effective discharge of patients from hospital needs to move from a functional focus on symptom management to a negotiation of quality of life that seeks to promote health for all parties involved.