Dose due to man-made radionuclides in terrestrial wild foods near Sellafield

Radiological dose implications for consumers of wild foods around Sellafield have been assessed. Habits were surveyed from 72 households, mostly within a few kilometres of Sellafield. A few people were included who lived further away but collect wild foods close to Sellafield. Dose estimates were based on measured gamma emitters, as well as 239Pu, 241Am, 14C and 129I in selected samples. In all cases, doses were dominated by 137Cs. One infant was identified who consumed wild food, giving an estimated effective dose of 0.3 microSv a(-1). In the age group 2 to 10 years a mean dose of 0.51 microSv a(-1), and a maximum of 2.8 microSv a(-1), were estimated. Intakes by adults were higher and resulted in more radiologically significant doses. The extreme individual received a dose of 32 microSv a(-1) largely due to consumption of honey that included contributions from the Chernobyl accident, and hedgerow fruits. This is comparable to doses to the critical group for consumption of conventional agricultural produce close to the Sellafield site. The 97.5th percentile dose, for all age groups of consumers taken together, was 16.6 microSv a(-1), or 6.2 microSv a(-1) if the contributions from Chernobyl are excluded. Considering the contributions from different foods to the whole group of 181 wild food consumers, the rank order is honey, blackberries and venison.

Is the incidence of acute appendicitis really falling?

To determine if there has been a genuine fall in the incidence of acute appendicitis, an epidemiological study using HAA and Korner datasets for the years 1975-1994 was carried out to identify those children and young adults undergoing appendicectomy for acute appendicitis. The overall incidence of acute appendicitis fell from 1.84/1000 to 1.17/1000. This fall was statistically significant (R2 = 0.74, P < 0.01). The decrease was significant in both males (overall reduction, 34%) and females (overall reduction, 40%). No significant reduction was observed in either males or females between 15 and 19 years of age. The overall reduction remains essentially unexplained, but may have implications for health planning and provision of services.

OB-GYN Consultants and Sharp the BirthPlace: an exemplar of nurse-midwife and obstetrician interdependence and integration

The "co-management" model of perinatal care as practiced at OB-GYN Consultants and Sharp The BirthPlace maximizes the practice strengths of both nurse-midwives and obstetricians. The nurse-midwife is the primary provider for 95% of the clients; high-risk women are referred to the physician as appropriate. The model provides extensive health education and an option of a freestanding birth center for low-risk women. In the face of rapid health care changes, which emphasize cost effectiveness, this model has appealing features for managed care systems.

More than motherhood? A feminist exploration of 'women's health' in papers indexed by CINAHL 1993-1995

Holism is claimed to be the signifying feature that sets women's health apart from traditional approaches to health care. As such, articles published in the nursing literature about women's health would, one might expect, reflect the centrality of holism to women's health care nursing. The findings of a study which examined the content and the focus of articles published about women's health in journals indexed by CINAHL in the period 1993-1995 challenge this assumption. It was found that women's health is a taken-for-granted notion and is used interchangeably and synonymously to refer to reproductive health, maternal health, neonatal health, family health and (hetero) sexual health. Confounding the view that holism is foundational to a women's health perspective, the papers forming the study's sample largely depict issues to do with women's health from a narrow and stereotypical perspective and with a bio-medical focus. Women were referred to as fragmented bodies, body parts and diseases, and were depicted as being passive and silent. By contrast, the voice (and the activity) of nurses and nursing's imperative to intervene was clearly discernible.

Mucosal addressin cell adhesion molecule-1 (MAdCAM-1). Its binding motif for alpha 4 beta 7 and role in experimental colitis

The integrin alpha 4 beta 7 and mucosal addressin cell adhesion molecule-1 (MAdCAM-1) are molecules involved in the normal recirculation of lymphocytes between the blood and the gastrointestinal tract. These molecules may play a complementary and significant role in animal models of colitis. We have investigated the structural interaction between alpha 4 beta 7 and MAdCAM-1. Site-directed mutagenesis studies of the MAdCAM-1 molecule has led to the identification of the amino acid residue (LDT) in the loop between beta strands C and D of the Ig-superfamily-like folds being involved in the adhesive and cell activation functions of MAdCAM-1 with alpha 4 beta 7.

A role for fibroblast growth factor signaling in the lobuloalveolar development of the mammary gland

The inappropriate expression of growth factors, or activating mutations of their receptors, have been implicated as causative factors in mouse and human mammary cancer. For example, it has been known for some time that three members of the fibroblast growth factor (FGF) family behave like oncogenes in virally induced mammary cancer of mice. In normal circumstances, signaling via FGF receptors is known to mediate growth, differentiation, and patterning, during embryogenesis and fetal development. A powerful approach to dissecting the roles for these signaling pathways is to determine the developmental consequences of abrogating their function in transgenic mice. In this review, we describe the use of dominant negative FGF receptors to evaluate the contribution of specific FGF signals in normal mammary gland development. These studies have revealed that normal lobuloalveolar development requires FGF signaling to the mammary epithelium, a function that is presumably usurped by MMTV in mouse mammary tumorigenesis.

Retrograde cerebral perfusion provides limited distribution of blood to the brain: a study in pigs

OBJECTIVE

The objective of this study was to investigate flow distribution during retrograde and antegrade cerebral perfusion with India ink as a marker.

METHODS

Ten pigs received cerebral perfusion with a solution containing 50% filtered India ink for 5 minutes either antegradely through both internal carotid arteries at a flow of 180 to 200 ml/min (n = 5) or retrogradely via the superior vena cava at a flow of 300 to 500 ml/min (n = 5). The brains were then fixed for quantitative measurement of the density of ink-filled capillaries (reported as a percentage of the total selected area). The assessment was done with the use of an in-house software program.

RESULTS

In the antegrade cerebral perfusion group, the intracranial arterial and venous systems were completely filled with ink. The gray matter was colored uniformly black, and light coloring was observed in the white matter. During retrograde cerebral perfusion, the majority of ink was returned to the inferior vena cava, and only a small amount of ink was found in the innominate artery draining from the brain. Massive ink filling was observed in the sagittal sinus and other venous sinuses in all the pigs. Vessels on the surface of the brain and large vessels in the brain were also well filled with ink. However, only 10% of capillaries were filled with ink during retrograde cerebral perfusion relative to the number observed with antegrade cerebral perfusion.

CONCLUSIONS

Retrograde cerebral perfusion supplies a limited amount of blood to brain tissue, which flows mainly through superficial and large deep cerebral vessels.

Lactate accumulation in the shell of the turtle Chrysemys picta bellii during anoxia at 3°C and 10°C

Lactate concentrations were measured in the shell and plasma of the turtle Chrysemys picta bellii after 3 months of submergence anoxia at 3&deg;C and during and after 9 days of submergence anoxia at 10&deg;C. Liver and skeletal muscle lactate levels were also measured in control and anoxic animals at each temperature. At 3&deg;C, mean shell lactate concentration (N=4) reached 133mmolkg-1shellmass and plasma lactate levels were 144mmoll-1; at 10&deg;C, shell and plasma lactate concentrations (N=5) rose in parallel during anoxic exposure, to 70.8mmolkg-1shellmass and 78.9mmoll-1, respectively, and returned in parallel to control levels during 9 days of recovery. At the end of the anoxic periods, an estimated 44% of the total body lactate resided in the shell at 3&deg;C and 43% at 10&deg;C, and indirect evidence suggests that the shell buffered these same fractions of the acid load. Because of the high lactate concentration per kilogram of shell water (416mmolkg-1 at 3&deg;C; 221mmolkg-1 at 10&deg;C) and the known formation of calcium lactate complexes, it is postulated that most of the lactate existed in the shell in combined form. I conclude that sequestration of lactate within the shell represents a potentially major adaptation to anoxic acidosis for this animal and, together with the previously described release of shell carbonates, may account for up to two-thirds of the total lactic acid buffering in this animal.

Morphogenesis on the move: cell-to-cell trafficking of plant regulatory proteins

It has been shown recently that some plant transcription factors that regulate cell fate during development can traffic through plasmodesmata-the intercellular channels that connect plant cells. This phenomenon helps explain the non-autonomous effects of many developmental mutations in plants and defines a novel mechanism by which cells signal to each other during development.

Fibroblast growth factor receptor signalling has a role in lobuloalveolar development of the mammary gland

We have used the mouse mammary tumor virus promoter to express two dominant negative (DN) fibroblast growth factor receptor (FGFR) isoforms in the mammary epithelium of transgenic mice. While expression of DN-FGFR1(IIIc) showed no discernible phenotype, a similar kinase negative form of FGFR2(IIIb) caused a marked impairment of lobuloalveolar development. The growth retardation was apparent by mid-pregnancy and persisted in the post-partum glands. Despite the substantial underdevelopment of the mammary gland there was a measurable lactational response, but it was insufficient to properly sustain the new-born pups. These findings demonstrate that fibroblast growth factor signalling is necessary for pregnancy dependent lobuloalveolar development of the mammary gland.

Feminism: a path to clinical knowledge development

Nurses are under increasing pressure to defend the efficacy, value and cost benefits of professional nursing care. Now more than ever, there is a need for nurses to undertake quality clinical research, through which practice may be shaped and guided. Feminist theory can provide a lens through which nurses may explore clinical issues. It also provides a framework by which socially constructed differences, such as gender and culture, may be incorporated into the design of clinical research projects. Because feminism is an openly political and transformative process, feminist concepts are suitable for use where the aim of the research is to catalyse practice change. This paper explores the use of feminism as a theoretical framework for nursing research.

A randomized trial of group outpatient visits for chronically ill older HMO members: the Cooperative Health Care Clinic

OBJECTIVE

To compare the impact of group outpatient visits to traditional "physician-patient dyad" care among older chronically ill HMO members on health services utilization and cost, self-reported health status, and patient and physician satisfaction.

DESIGN

A 1-year randomized trial.

SETTING

A group model HMO in the Denver Metropolitan area.

PARTICIPANTS

Three hundred twenty-one members aged 65 and older, randomized to a group visit intervention (n = 160) or to usual care (n = 161).

INTERVENTION

Patients with high health services utilization and one or more chronic conditions had monthly group visits with their primary care physician and nurse. Visits included health education, prevention measures, opportunities for socialization, mutual support, and for one-to-one consultations with their physician, where necessary.

MEASUREMENTS

Health services utilization and associated cost, health status, and patient and physician satisfaction.

RESULTS

Outcome measures obtained after a 1-year follow-up period showed that group participants had fewer emergency room visits (P = .009), visits to subspecialists (P = .028), and repeat hospital admissions per patient (P = .051). Group participants made more visits (P = .021) and calls (P = .038) to nurses than control group patients and fewer calls to physicians (P = .019). In addition, a greater percentage of group participants received influenza and pneumonia vaccinations (P < .001). Group participants had greater overall satisfaction with care (P = .019), and participating physicians reported higher levels of satisfaction with the groups than with individual care. No differences were observed between groups on self-reported health and functional status. Cost of care per member per month was $14.79 less for the group participants.

CONCLUSIONS

Group visits for chronically ill patients reduce repeat hospital admissions and emergency care use, reduce cost of care, deliver certain preventive services more effectively, and increase patient and physician satisfaction.

Antibody to Haemophilus ducreyi among trucking company workers in Kenya

BACKGROUND AND OBJECTIVES

To determine the prevalence, correlates, and incidence of Haemophilus ducreyi antibodies, a cohort of East African trucking company employees was evaluated.

STUDY DESIGN

Human immunodeficiency virus (HIV)-1-seronegative men working in six trucking companies in Mombasa, Kenya, were evaluated with a questionnaire and serologic testing for antibodies to H. ducreyi and other sexually transmitted pathogens. Men who were initially H. ducreyi seronegative were retested at 1 year of follow-up.

RESULTS

The H. ducreyi seroprevalence among 501 men at enrollment was 26.5%. Seropositivity was significantly associated with older age, married status, years of active sex life, number of sex partners in the past year, history of unprotected sex with a prostitute in the past year, and history of alcohol intake (all P values < 0.01). Occupational travel for more than 14 days per month was also significantly associated with H. ducreyi seropositivity (odds ratio [OR] 2.1, 95% confidence interval [CI] 1.3-3.2). Using multivariate analysis, H. ducreyi seropositivity was independently associated with age, married status, history of sex with a prostitute, and history of alcohol intake. Presence of H. ducreyi antibodies was significantly associated with seropositivity to the other major genital ulcerative pathogens, Treponema pallidum (OR 4.3, 95% CI 2.2-8.3), herpes simplex virus type 2 (OR 4.9, 95% CI 2.0-11.5), and Chlamydia trachomatis (OR 3.2, 95% CI 1.5-6.9). These associations remained significant after adjusting for demographic and exposure variables. The incidence of seroconversion to H. ducreyi antibodies was 3.6 per 100 person years.

CONCLUSIONS

Serologic evidence of H. ducreyi infection was common among male trucking company employees. H. ducreyi seropositivity is an objective marker of high-risk behavior and is associated with serologic evidence of other ulcerative sexually transmitted diseases.

In uncharted waters: confronting the culture of silence in a residential care institution

This paper describes a study grounded in feminism, which explored the experiences of three registered nurses who were employed in a residential care institution in which they believed the standard of care to be unacceptably poor. Ultimately, the nurses became 'whistle blowers'. Data surrounding these events were gathered through serial encounters and analysed using feminist interpretive methods. Three distinct phases were revealed: (i) trepidation and optimizm; (ii) barriers and obstacles; and (iii) disillusionment and defeat. It was in this final phase that the whistle blowing occurred. For these women, whistle blowing was an intervention of last resort; a stressful and negative event that carried personal and professional cost. Issues pertaining to professional autonomy and patient advocacy are raised, together with concerns surrounding the appropriation by business people of the language and images of nursing, and the power of these people to negatively impact upon nursing practice.

Proliferin transport and binding in the mouse fetus

Proliferin (PLF), a member of the PRL/GH family secreted by the placenta, can be detected in both the maternal and fetal compartments. We now show that PLF immunoreactivity can be detected in association with the yolk sac, consistent with the transport of PLF across this structure into the amniotic fluid. Furthermore, PLF is transported across the extraembryonic membranes in isolated conceptuses that are placed in culture, and specific binding sites for PLF are detected in these embryos. The major binding sites for PLF in the cultured conceptus correspond to sites at which endogenous PLF localizes in the fetus, including developing vertebral and vascular structures. Similar binding patterns were also detected for PLF that was incubated with fetal sections. Competition and comparative binding studies indicate that the insulin-like growth factor II/mannose 6-phosphate receptor is involved in PLF binding to specific cells in the fetus. These results suggest that in addition to the effects of PLF in the placenta on neovascularization and in the maternal uterus on cell proliferation, PLF may also act at specific sites in the developing fetus.

Transfer rates from freestanding birth centers. A comparison with the National Birth Center Study

This article reviews retrospective data derived from Sharp The BirthPlace. San Diego for 1993-94 and from the University of California. Irvine, Birthing Center for 1994 and compares these findings to data obtained from the National Birth Center Study (NBCS). The focus of this article is on intrapartum transfer rates from the two freestanding birth centers as a critical clinical indicator. Cause-specific transfer rates were calculated for eight clinical conditions. Data suggest that cause-specific intrapartum transfer rates are influenced by factors such as risk profile of the client population, distance to the referral center and mechanisms of transfer, definitions and diagnostic criteria used, and clinical practice guidelines. Reports from the literature, such as NBCS data, might serve as points of reference, but are likely not appropriate baseline indicators (benchmarks of "best practice") for clinical events, against which individual performance can be measured; rather, these benchmarks should be individually defined, based on characteristics unique to each birth center.

Prior knowledge and reading comprehension ability of deaf adolescents

Fifty-one severely to profoundly deaf students (mean dB hearing loss = 89) were randomly assigned to two groups that differed by the type of probes (short or long) used to elicit prior knowledge (PK). PK scores were used to predict reading comprehension (RC), which was assessed by students' responses to three types of questions: test-explicit (TE), text-implicit (TI), and script-implicit (SI). Multiple regression models with PK scores and scores from a standardized achievement test (Stanford Achievement Test - Hearing Impaired Version, reading subtest) were also used to predict RC. The regression model showed that, for the group pretested with an in-depth, or long, probe of PK, the best predictor of RC was the ability to answer TE and SI questions. We present discussions of the observed differences in comprehension as a function of long and short knowledge probes and the use of three question types, together with implications for instruction.

Defence against the immune barrage: helminth survival strategies

Parasites have generated a range of countermeasures against the host immune system which allows their survival long enough for reproduction to occur. Parasite subsistence is enhanced by evasion of the immune response utilizing mechanisms such as antigenic variation of exposed immunogenic proteins, shedding of surface proteins which are the target of an immune response, and protease production to neutralise specific anti-parasite immune components. Recent advances in the fields of immunology and parasitology have highlighted a range of mechanisms by which the parasite actively modulates the immune response to allow survival. Parasite factors can directly suppress the function of certain subsets of immune cells as well as stimulating other cell populations which have suppressive activity. Strategies such as the skewing of the type 1-type 2 cytokine profile to that of a less appropriate response, and the mimicry of host immune regulatory proteins are becoming more widely acknowledged as means by which helminths enhance their survival. An illustration of the extent by which parasites can exploit host immune components is emphasized by the use of host cytokines as parasite growth factors. This review will examine some of the strategies developed by helminths which enables them not only to survive in the host, but also to prosper.

Mucosal addressin cell adhesion molecule-1: a structural and functional analysis demarcates the integrin binding motif

The leukocyte integrin receptor, alpha 4 beta 7, and the mucosal addressin cell adhesion molecule-1 (MAdCAM-1) are postulated to be important in regulating lymphocyte trafficking to normal intestine. Here we provide the first description of MAdCAM-1 expression in inflamed intestine. Using mouse models of experimentally induced colitis, we show a concordant increase in MAdCAM-1 expression associated with increased cellular infiltrates in areas of intestinal inflammation. To understand more of the molecular nature of the interactions between MAdCAM-1 and its leukocyte ligand, the alpha 4 beta 7 integrin receptor, we have analyzed the structural and functional properties of chimeric recombinant MAdCAM-1 proteins in vitro. Using site-directed mutagenesis and molecular modeling, we demarcate the alpha 4 beta 7 binding motif as three linear residues within the C-D loop in the first domain of MAdCAM-1. Mutation of residue L40, D41, or T42 in the first domain completely abrogates alpha 4 beta 7+ cell binding and cellular activation. Mutagenesis of other residues in the first domain do not impact these functions. We have modeled peptides based on the predicted structure of the alpha 4 beta 7 integrin binding motif on MAdCAM-1 and are able to show specific and selective blocking of cell binding. These observations suggest that the amino acid residues LDT on MAdCAM-1 play a role in the interaction with alpha 4 beta 7 in cell adherence and cell activation.

Mucosal addressin cell adhesion molecule-1: a structural and functional analysis demarcates the integrin binding motif

The leukocyte integrin receptor, alpha 4 beta 7, and the mucosal addressin cell adhesion molecule-1 (MAdCAM-1) are postulated to be important in regulating lymphocyte trafficking to normal intestine. Here we provide the first description of MAdCAM-1 expression in inflamed intestine. Using mouse models of experimentally induced colitis, we show a concordant increase in MAdCAM-1 expression associated with increased cellular infiltrates in areas of intestinal inflammation. To understand more of the molecular nature of the interactions between MAdCAM-1 and its leukocyte ligand, the alpha 4 beta 7 integrin receptor, we have analyzed the structural and functional properties of chimeric recombinant MAdCAM-1 proteins in vitro. Using site-directed mutagenesis and molecular modeling, we demarcate the alpha 4 beta 7 binding motif as three linear residues within the C-D loop in the first domain of MAdCAM-1. Mutation of residue L40, D41, or T42 in the first domain completely abrogates alpha 4 beta 7+ cell binding and cellular activation. Mutagenesis of other residues in the first domain do not impact these functions. We have modeled peptides based on the predicted structure of the alpha 4 beta 7 integrin binding motif on MAdCAM-1 and are able to show specific and selective blocking of cell binding. These observations suggest that the amino acid residues LDT on MAdCAM-1 play a role in the interaction with alpha 4 beta 7 in cell adherence and cell activation.