Improving a Web-Based Tool to Support Older Adults to Stay Independent at Home: Qualitative Study

Background

Older adults desire to stay independent at home for as long as possible. We developed an interactive website to inform older adults and caregivers about ways to achieve this.

Objective

This study aimed to perform an in-depth exploration among potential end users about how to improve the interactive website to better inform older adults and caregivers about ways to stay independent at home.

Methods

To complement the results of a quantitative survey on the usability and acceptability of the website before implementation, we conducted a qualitative descriptive study. Using multiple recruitment strategies, we recruited a purposeful sample of older adults (aged ≥65 years) and caregivers of older adults struggling to stay independent at home. We conducted face-to-face or telephonic interviews in either English or French. In addition, we collected sociodemographic characteristics, other characteristics of participants (eg, health, digital profile, and perception of retirement homes), and experiences with using the website (factors facilitating the use of the website, barriers to its use, and suggestions for improvement). Interviews were audio recorded, transcribed verbatim, and thematically analyzed by two researchers.

Results

We recruited 15 participants, including 5 older adults (mean age 75 years, SD 6) and 10 caregivers (mean age 57 years, SD 14). The mean interview time was 32 min (SD 14). Most older adults had either mobility or health problems or both, and many of them were receiving home care services (eg, blood pressure measurement and body care). Overall, participants found the website easy to navigate using a computer, reassuring, and useful for obtaining information. Barriers were related to navigation (eg, difficult to navigate with a cellphone), relevance (eg, no specific section for caregivers), realism (eg, some resources presented are not state funded), understandability (eg, the actors’ accents were difficult to understand), and accessibility (eg, not adapted for low digital literacy). Suggestions for improvement included a needs assessment section to direct users to the support appropriate to their needs, addition of information about moving into residential care, a section for caregivers, distinction between state-provided and private support services, simpler language, expansion of content to be relevant to all of Canada, and video subtitles for the hearing impaired.

Conclusions

Users provided a wealth of information about the needs of older adults who were facing a loss of autonomy and about what such a website could usefully provide. The request for less generic and more personalized information reflects the wide range of needs that electronic health innovations, such as our interactive website, need to address. After integrating the changes suggested, the new website—Support for Older Adults to Stay Independent at Home (SUSTAIN)—will be implemented and made available to better assist older adults and caregivers in staying independent at home.

Cerebral Ketones Detected by 3T MR Spectroscopy in Patients with High-Grade Glioma on an Atkins-Based Diet

BACKGROUND AND PURPOSE

Ketogenic diets are being explored as a possible treatment for several neurological diseases, but the physiologic impact on the brain is unknown. The objective of this study was to evaluate the feasibility of 3T MR spectroscopy to monitor brain ketone levels in patients with high-grade gliomas who were on a ketogenic diet (a modified Atkins diet) for 8 weeks.

MATERIALS AND METHODS

Paired pre- and post-ketogenic diet MR spectroscopy data from both the lesion and contralateral hemisphere were analyzed using LCModel software in 10 patients.

RESULTS

At baseline, the ketone bodies acetone and β-hydroxybutyrate were nearly undetectable, but by week 8, they increased in the lesion for both acetone (0.06 ± 0.03 ≥ 0.27 ± 0.06 IU, P = .005) and β-hydroxybutyrate (0.07 ± 0.07 ≥ 0.79 ± 0.32 IU, P = .046). In the contralateral brain, acetone was also significantly increased (0.041 ± 0.01 ≥ 0.16 ± 0.04 IU, P = .004), but not β-hydroxybutyrate. Acetone was detected in 9/10 patients at week 8, and β-hydroxybutyrate, in 5/10. Acetone concentrations in the contralateral brain correlated strongly with higher urine ketones (r = 0.87, P = .001) and lower fasting glucose (r = -0.67, P = .03). Acetoacetate was largely undetectable. Small-but-statistically significant decreases in NAA were also observed in the contralateral hemisphere at 8 weeks.

CONCLUSIONS

This study suggests that 3T MR spectroscopy is feasible for detecting small cerebral metabolic changes associated with a ketogenic diet, provided that appropriate methodology is used.

Approaches to considering sex and gender in continuous professional development for health and social care professionals: An emerging paradigm

Consideration of sex and gender in research and clinical practice is necessary to redress health inequities and reduce knowledge gaps. As all health professionals must maintain and update their skills throughout their career, developing innovative continuing professional education programs that integrate sex and gender issues holds great promise for reducing these gaps. This article proposes new approaches to partnership, team development, pedagogical theory, content development, evaluation and data management that will advance the integration of sex and gender in continuing professional development (CPD). Our perspectives build on an intersectoral and interprofessional research team that includes several perspectives, including those of CPD, health systems, knowledge translation and sex and gender.

Development of a decision aid for cardiopulmonary resuscitation and invasive mechanical ventilation in the intensive care unit employing user-centered design and a wiki platform for rapid prototyping

BACKGROUND

Upon admission to an intensive care unit (ICU), all patients should discuss their goals of care and express their wishes concerning life-sustaining interventions (e.g., cardiopulmonary resuscitation (CPR)). Without such discussions, interventions that prolong life at the cost of decreasing its quality may be used without appropriate guidance from patients.

OBJECTIVES

To adapt an existing decision aid about CPR to create a wiki-based decision aid individually adapted to each patient's risk factors; and to document the use of a wiki platform for this purpose.

METHODS

We conducted three weeks of ethnographic observation in our ICU to observe intensivists and patients discussing goals of care and to identify their needs regarding decision making. We interviewed intensivists individually. Then we conducted three rounds of rapid prototyping involving 15 patients and 11 health professionals. We recorded and analyzed all discussions, interviews and comments, and collected sociodemographic data. Using a wiki, a website that allows multiple users to contribute or edit content, we adapted the decision aid accordingly and added the Good Outcome Following Attempted Resuscitation (GO-FAR) prediction rule calculator.

RESULTS

We added discussion of invasive mechanical ventilation. The final decision aid comprises values clarification, risks and benefits of CPR and invasive mechanical ventilation, statistics about CPR, and a synthesis section. We added the GO-FAR prediction calculator as an online adjunct to the decision aid. Although three rounds of rapid prototyping simplified the information in the decision aid, 60% (n = 3/5) of the patients involved in the last cycle still did not understand its purpose.

CONCLUSIONS

Wikis and user-centered design can be used to adapt decision aids to users' needs and local contexts. Our wiki platform allows other centers to adapt our tools, reducing duplication and accelerating scale-up. Physicians need training in shared decision making skills about goals of care and in using the decision aid. A video version of the decision aid could clarify its purpose.

Deciding How to Stay Independent at Home in Later Years: Development and Acceptability Testing of an Informative Web-Based Module

Background

Seniors with loss of autonomy may face decisions about whether they should stay at home or move elsewhere. Most seniors would prefer to stay home and be independent for as long as possible, but most are unaware of options that would make this possible.

Objective

The study aimed to develop and test the acceptability of an interactive website for seniors, their caregivers, and health professionals with short interlinked videos presenting information about options for staying independent at home.

Methods

The approach for design and data collection varied, involving a multipronged, user-centered design of the development process, qualitative interviews, and end-user feedback to determine content (ie, needs assessment) in phase I; module development (in English and French) in phase II; and survey to test usability and acceptability with end users in phase III. Phase I participants were a convenience sample of end users, that is, seniors, caregivers, and professionals with expertise in modifiable factors (eg, day centers, home redesign, equipment, community activities, and finances), enabling seniors to stay independent at home for longer in Quebec and Alberta, Canada. Phase II participants were bilingual actors; phase III participants included phase I participants and new participants recruited through snowballing. Qualitative interviews were thematically analyzed in phase II to determine relevant topics for the video-scripts, which were user-checked by interview participants. In phase III, the results of a usability questionnaire were analyzed using descriptive statistics.

Results

In phase I, interviews with 29 stakeholders, including 4 seniors, 3 caregivers, and 22 professionals, showed a need for a one-stop information resource about options for staying independent at home. They raised issues relating to 6 categories: cognitive autonomy, psychological or mental well-being, functional autonomy, social autonomy, financial autonomy, and people involved. A script was developed and evaluated by participants. In phase II, after 4 days in a studio with 15 bilingual actors, 30 videos were made of various experts (eg, family doctor, home care nurse, and social worker) presenting options and guidance for the decision-making process. These were integrated into an interactive website, which included a comments tool for visitors to add information. In phase III (n=21), 8 seniors (7 women, mean age 75 years), 7 caregivers, and 6 professionals evaluated the acceptability of the module and suggested improvements. Clarity of the videos scored 3.6 out of 4, length was considered right by 17 (separate videos) and 13 participants (all videos together), and 18 participants considered the module acceptable. They suggested that information should be tailored more, and that seniors may need someone to help navigate it.

Conclusions

Our interactive website with interlinked videos presenting information about options for staying independent at home was deemed acceptable and potentially helpful by a diverse group of stakeholders.

Is Shared Decision Making a Utopian Dream or an Achievable Goal?

The idea of shared decision making (SDM) between patient and physician grew out of a generalized challenge to traditional social hierarchies that occurred in the middle of the last century. Governments have espoused SDM, thousands of articles about it have been published, and evidence has shown that it improves some of the healthcare processes as well as patient outcomes. Yet it has not been widely adopted. From their cross-disciplinary perspective (practical theology and clinical medicine), the authors locate this reluctance in the unfolding of scientific paradigm shifts, summarize the perceived risks and benefits of SDM and the evidence for each, and suggest practical, achievable approaches for clinicians. Finally, they explore some important emerging territories for SDM.

Development of a decision guide to support the elderly in decision making about location of care: an iterative, user-centered design

PLAIN ENGLISH SUMMARY

For the elderly to get the care and services they need, they may need to make the difficult decision about staying in their home or moving to another home. Many other people may be involved in their care too (friends, family and healthcare providers), and can support them in making the decision. We asked informal caregivers of elderly people to help us develop a decision guide to support them and their loved ones in making this decision. This guide will be used by health providers in home care who are trained to help people make decisions. The guide is in French and English. To design and test this decision guide we involved elderly people, their caregivers and health administrators. We first asked them what they needed for making the decision, and then designed a first version of the guide. Then we asked them to look at it and give feedback, which was used to make the final version. We then used scientific criteria to check its content and the language used. The final decision guide was acceptable to the caregivers, their elderly loved ones, and the health administrators. The guide is currently being evaluated in a large research project with home care teams in the province of Quebec.

ABSTRACT

Background As they grow older, many elderly people are faced with the difficult and preference-sensitive decision about staying in their home or moving to a residence better adapted to their evolving care needs. We aimed to develop an English and French decision aid (DA) for elderly people facing this decision, and to involve end-users in all phases of the development process. Methods A three-cycle design with involvement of end-users in Quebec. End-users were elderly people (n = 4) caregivers of the elderly (n = 5), health administrators involved in home-care service delivery or policy (n = 6) and an interprofessional research team (n = 19). Cycle 1: Decisional needs assessment and development of the first prototype based on existing tools and input from end-users; overview of reviews examining the impact of location of care on elderly people's health outcomes. Cycle 2: Usability testing with end-users, adaptation of prototype. Cycle 3: Refinement of the prototype with a linguist, graphic designer and end-users. The final prototype underwent readability testing and an International Patient Decision Aids (IPDAS) criteria compatibility assessment to verify minimal requirements for decision aids and was tested for usability by the elderly. ResultsCycle 1: We used the Ottawa Personal Decision Guide to design a first prototype. As the overview of reviews did not find definitive evidence regarding optimal locations of care for elderly people, we were not able to add evidence-based advantages and disadvantages to the guide. Cycle 2: Overall, the caregivers and health administrators who evaluated the prototype (n = 10) were positive. In response to their suggestions, we deleted some elements (overview of pros, cons, and consequences of the options) that were necessary to qualify the tool as a DA and renamed it a "decision guide". Cycle 3: We developed French and English versions of the guide, readable at a primary school level. The elderly judged the guide as acceptable. Conclusion We developed a decision guide to support elderly people and their caregivers in decision making about location of care. This paper is one of few to report on a fully collaborative approach to decision guide development that involves end-users at every stage (caregivers and health administrators early on, the frail elderly in the final stages). The guide is currently being evaluated in a cluster randomized trial. Trial registration: NCT02244359.

Abstract P2-05-25: TIMP-4 expression correlates with disease progression among HER2-positive breast cancers

Breast cancer with HER2 gene amplification accounts for 20-25% of invasive breast cancer. HER2 activates the PI3K/Akt and MAPK pathways promoting survival and cell proliferation resulting in aggressive biological behavior and poorer prognosis for the patient. Although trastuzumab (Herceptin®), a recombinant humanized antibody, offers effective treatment of HER2-positive cancers, a proportion of patients will not respond to trastuzumab-based regimens and those who do respond can lose clinical benefit during the late stages of their treatment.

In this IRB-approved study we have assessed HER2 and LuminalB subtypes of invasive breast cancer from an archival collection together with specimens collected in an on-going prospective study for the expression of tissue inhibitor of metalloproteinase-4 (TIMP-4), an inducer of the PI3K/Akt pathway and its possible correlation to trastuzumab resistance. Circulating TIMP-4 in the stroma binds to CD63 on the tumor epithelial cells and initiates a signaling cascade through interaction with β1-integrin.

We have previously demonstrated that elevated levels of TIMP-4 confers poor survival prognosis for triple-negative breast cancers. Genomics data found at TCGA, cBioPortal for Cancer Genomics1 have showed that TIMP-4 is amplified in 24% of breast cancer patients.

Therefore, we propose that the reported ˜20% of HER2-positive patients that will not respond to trastuzumab could in fact be TIMP-4 positive and have active PI3K/Akt signaling. In this on-going study, we have to date examined twenty-nine patients with HER2 gene amplification. Among these, eight had elevated levels of TIMP-4 as determined by immunohistochemistry, and seven had progression of their disease within one year of starting systemic therapy (all with metastasis to brain) while one had local recurrence 5 years after starting therapy. Two of these patients had stage IA disease, one had IIA, three had IIB and two were diagnosed with stage IIIC disease. These results suggest that TIMP-4 amplification could be, at least in part, responsible for the trastuzumab resistance due to TIMP4's ability to promote survival and cell proliferation by a continuous activation of the PI3K/Akt pathway.

In an attempt to test if a monoclonal antibody specific for human TIMP-4 could be used to prevent or alleviate the trastuzumab resistance, we are using human breast cancer cell-lines with amplified HER2, with and without CD63 expression as well as a CD63 knock-out line. From these experiments we hope to learn if treating for TIMP-4 could be an approach for future clinical intervention for the patients that have HER2 gene amplification and elevated levels of TIMP-4.

1 Gao et al. Sci Signal. 2013 and Cermi et al . Cancer Discov. 2012.

Citation Format: Isaac KM, Zemba-Palko V, Sabol JL, Blair L, Behbod F, Wallon UM. TIMP-4 expression correlates with disease progression among HER2-positive breast cancers. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-05-25.

Effects of active HCV replication on neurologic status in HIV RNA virally suppressed patients

BACKGROUND

Hepatitis C virus (HCV) is a frequent copathogen with HIV. Both viruses appear to replicate in the brain and both are implicated in neurocognitive and peripheral neuropathy syndromes. Interaction of the viruses is likely to be complicated and better understanding of the contributions of each virus will be necessary to make evidence-based therapeutic decisions.

METHODS

This study was designed to determine if active HCV infection, identified by quantitative HCV RNA determination, is associated with increased neurocognitive deficits or excess development of distal sensory peripheral neuropathy in HIV coinfected patients with stable HIV viral suppression. The AIDS Clinical Trials Group Longitudinal Linked Randomized Trials (ALLRT) study was the source of subjects with known HIV treatment status, neurocognitive and neuropathy evaluations, and HCV status. Subjects were selected based on HCV antibody status (249 positive; 310 negative).

RESULTS

HCV RNA viral loads were detectable in 172 participants with controlled HIV infection and available neurologic evaluations in the ALLRT. These participants were compared with 345 participants with undetectable HCV viral load and the same inclusion criteria from the same cohort. Neurocognitive performance measured by Trail-Making A or B and digit symbol testing was not dissimilar between the 2 groups. In addition, there was no significant association between active HCV replication and distal sensory neuropathy.

CONCLUSION

Clinically significant neurocognitive dysfunction and peripheral neuropathy were not exacerbated by active hepatitis C virus infection in the setting of optimally treated HIV infection.

Green fluorescent protein in the study of neuronal signaling pathways

In recent years, techniques have been established for transiently co-transfecting cells with cDNA of the jellyfish green fluorescent protein (GFP), a reporter gene that encodes a non-toxic marker. This approach can be applied to primary neurons where it has become especially useful for the study of neuronal second messenger pathways. This unit describes procedures for transfecting neurons in primary culture: transfection with GFP DNA, including co-transfecting with separate GFP and gene-of-interest constructs, transfecting with a single construct containing the gene of interest fused to a GFP gene, and transfecting with a single construct containing separate gene-of-interest and GFP cassettes. Also included is a method for the rapid, large-scale preparation of a nearly homogeneous population of neurons from rat cerebellum. The Commentary provides several examples of how this approach can be applied to specific biological questions on neuronal signaling pathways.

The mas oncogene as a neural peptide receptor: expression, regulation and mechanism of action

The human mas oncogene, which renders transfected NIH/3T3 cells tumorigenic, was identified as a subtype of angiotensin receptor by transient expression in Xenopus oocytes and stable expression in the mammalian neuronal cell line, NG115-401L. The mas receptor preferentially recognizes angiotensin III, and is expressed at high levels in brain. The mas/angiotensin receptor functions through the breakdown of inositol lipids and can drive DNA synthesis, unlike another inositol-linked peptide receptor, that for bradykinin. Comparative analysis of several early biochemical events elicited by either angiotensin or bradykinin stimulation of mas-transfected cells has not indicated a specific difference correlated with mitogenic activity. In particular, the inositol lipid kinase, phosphatidylinositol-3-kinase, thought to be involved in the mitogenic mechanism of platelet-derived growth factor receptors, is unaffected by activation of mas. These results have shown that a proto-oncogene encodes a neural peptide receptor, indicating that peptide receptors may be involved in differentiation and proliferation processes, as are other identified proto-oncogenes.

Bayesian spatial analysis of a national urinary schistosomiasis questionnaire to assist geographic targeting of schistosomiasis control in Tanzania, East Africa

Spatial modelling was applied to self-reported schistosomiasis data from over 2.5 million school students from 12,399 schools in all regions of mainland Tanzania. The aims were to derive statistically robust prevalence estimates in small geographical units (wards), to identify spatial clusters of high and low prevalence and to quantify uncertainty surrounding prevalence estimates. The objective was to permit informed decision-making for targeting of resources by the Tanzanian national schistosomiasis control programme. Bayesian logistic regression models were constructed to investigate the risk of schistosomiasis in each ward, based on the prevalence of self-reported schistosomiasis and blood in urine. Models contained covariates representing climatic and demographic effects and random effects for spatial clustering. Degree of urbanisation, median elevation of the ward and median normalised difference vegetation index (NDVI) were significantly and negatively associated with schistosomiasis prevalence. Most regions contained wards that had >95% certainty of schistosomiasis prevalence being >10%, the selected threshold for bi-annual mass chemotherapy of school-age children. Wards with >95% certainty of schistosomiasis prevalence being >30%, the selected threshold for annual mass chemotherapy of school-age children, were clustered in north-western, south-western and south-eastern regions. Large sample sizes in most wards meant raw prevalence estimates were robust. However, when uncertainties were investigated, intervention status was equivocal in 6.7–13.0% of wards depending on the criterion used. The resulting maps are being used to plan the distribution of praziquantel to participating districts; they will be applied to prioritising control in those wards where prevalence was unequivocally above thresholds for intervention and might direct decision-makers to obtain more information in wards where intervention status was uncertain.

KIR genotyping by reverse sequence-specific oligonucleotide methodology

Recent studies suggest that killer cell immunoglobulin-like receptors (KIR) genotyping may be relevant to bone marrow/stem cell transplantation. The objective of this research was to develop a bead-based reverse sequence-specific oligonucleotide DNA hybridization assay for KIR genotyping using the Luminex platform. The oligonucleotide probes were designed to recognize 14 currently known KIR genes and two pseudogenes, as well as null alleles. A unique probe design was used to allow detection of two cis-polymorphic regions for typing of KIR2DS4, because the functioning alleles cannot readily be assigned by conventional probe detection systems. Assay performance was validated using DNA samples previously typed by the 13th International Histocompatibility Working Group with 100% concordant results.

Dose-dependent schistosome-induced mortality and morbidity risk elevates host reproductive effort

Parasitism changes the host environment and may influence resource allocation between reproductive effort and somatic maintenance. We characterized the impact of dose-dependent schistosome exposure and/or infection establishment on intermediate host survival and reproduction. Four matched groups of Biomphalaria glabrata snails were individually exposed to increasing doses of Schistosoma mansoni parasites, with a fifth control group remaining unexposed. Increased mortality was observed amongst both snails infected and also those snails exposed to the parasite but within which infection did not establish, although only exposed but uninfected snails showed a dose-dependent increase in mortality. Snails also facultatively altered their reproductive output in response to parasite exposure: egg mass production decreased with increasing parasite dose in patently infected snails, whilst, in contrast, exposed but uninfected snails demonstrated a positive association between egg mass production and parasite dose in the post-patent period. These results uniquely suggest an exposure-dose-dependent post-patent fecundity compensation occurring in relation to the risk of future parasite-associated mortality.

Do Hosts and Parasites Coevolve? Empirical Support from the Schistosoma System

Coevolution between host and parasite is, in principle, a powerful determinant of the biology and genetics of infection and disease. However, coevolution is difficult to demonstrate rigorously in practice and therefore has rarely been observed empirically, particularly in animal-parasite systems. Research on host-schistosome interactions has the potential for making an important contribution to the study of coevolution or reciprocal adaptation. This may be particularly pertinent because schistosomes represent an indirectly transmitted macroparasite, so often overlooked among both theoretical and empirical studies. Here we present ideas and experiments on host-schistosome interactions, in part reviewed from published work but focusing in particular on preliminary novel data from our ongoing studies of potential host-schistosome evolution and coevolution in the laboratory. The article is split into three main sections: we first focus on the evidence for evolution in the host, then in the parasite, before combining both to illustrate the gathering evidence of host-parasite coevolution in the snail-schistosome system. In particular, we demonstrate that genetic architecture, variability, and selective pressures are present for the evolution of resistance and susceptibility, virulence, and infectivity to occur, the mechanisms allowing such polymorphisms to be maintained, and that hosts and parasites appear to have reciprocal effects on each other's phenotype and genotype.

Enhancing capacity for cardiovascular disease prevention: an overview of the British Columbia Heart Health Dissemination Research Project

British Columbia (population 3.88 million) is located on the West Coast of Canada (Statistics Canada, 1996). Primary resource activities are the province's traditional sources of economic strength, but there is also a growing economy based on knowledge-intensive secondary manufacturing, high-technology, tourism, film and international business (Ministry of Employment and Investment, 2000). Approximately one-third of the government's total expenditures go to health care (BC Stats, 2000). In 1997, health care in BC was regionalized and responsibility for health services decentralized to 52 health authorities serving eighteen regions.

Mutagenicity at the Hprt locus in T cells of female mice following inhalation exposures to low levels of 1,3-butadiene

A study was conducted to test the hypothesis that repeated low level exposures to 1,3-butadiene (BD), approaching the OSHA occupational threshold for this chemical, produce a significant mutagenic response in mice. Female B6C3F1 mice (4-5 weeks of age) were exposed by inhalation for 2 weeks (6 h/day, 5 days/week) to 0 or 3 ppm BD, and then necropsied at 4 weeks after the cessation of exposures to measure the frequency of mutations (MF) at the Hprt locus using the T-lymphocyte clonal assay. At necropsy, T cells were isolated from spleen and cultured in the presence of mitogen, growth factors, and a selection agent. Cells were scored for growth on days 8-9 after plating to determine cloning efficiencies (CEs) and Hprt MFs. There was a marginal but significant reduction in the growth of splenic T cells from mice exposed to 3 ppm (n=27) compared with control mice (n=24) (P=0.004), suggesting the occurrence of BD-induced cytotoxicity at this low exposure concentration. In addition, the average Hprt MF in mice exposed to 3 ppm BD [1.54+/-0.82 (S.D.)x10(-6)] was significantly increased by 1.6-fold over the average control value of 0.96+/-0.51 (S.D.)x10(-6) (P=0.004). Comparisons of these data to earlier Hprt mutagenicity studies of mice exposed to high concentrations of BD (where significant mutagenic but not cytotoxic effects were observed) indicate that the ability to detect the cytotoxic and mutagenic responses of T cells to low levels of BD was enhanced by using a much larger sample size than usual for both the control and treatment groups. Additional analyses of the quantitative relationships between CE and MF demonstrated that CE had no significant effect upon MF values in sham-exposed control mice or mice exposed to low-level BD. Furthermore, the approaches for assessing the impact of CE and clonality on Hprt MFs in these control and BD-exposed mice were applied with the same rigor as in in vivo Hprt mutagenicity studies in human children. The overall study results support the conclusion that short-term low-level BD exposure is mutagenic in the mouse.

Alkaline phosphatase knock-out mice recapitulate the metabolic and skeletal defects of infantile hypophosphatasia

Hypophosphatasia is an inborn error of metabolism characterized by deficient activity of the tissue-nonspecific isoenzyme of alkaline phosphatase (TNSALP) and skeletal disease due to impaired mineralization of cartilage and bone matrix. We investigated two independently generated TNSALP gene knock-out mouse strains as potential models for hypophosphatasia. Homozygous mice (-/-) had < 1% of wild-type plasma TNSALP activity; heterozygotes had the predicted mean of approximately 50%. Phosphoethanolamine, inorganic pyrophosphate, and pyridoxal 5'-phosphate are putative natural substrates for TNSALP and all were increased endogenously in the knock-out mice. Skeletal disease first appeared radiographically at approximately 10 days of age and featured worsening rachitic changes, osteopenia, and fracture. Histologic studies revealed developmental arrest of chondrocyte differentiation in epiphyses and in growth plates with diminished or absent hypertrophic zones. Progressive osteoidosis from defective skeletal matrix mineralization was noted but not associated with features of secondary hyperparathyroidism. Plasma and urine calcium and phosphate levels were unremarkable. Our findings demonstrate that TNSALP knock-out mice are a good model for the infantile form of hypophosphatasia and provide compelling evidence for an important role for TNSALP in postnatal development and mineralization of the murine skeleton.

Martyrdom by toads' tongues. Early Canadian doctors and their victims

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Beaver kidneys at your bedside. Oldest hospital in Canada has seen it all

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Cutting and pasting in Quebec. Community health centres and health care reform

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Iraq: dying voices of authority

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Inhaled nitric oxide in acute respiratory distress syndrome: a pilot randomized controlled study

This pilot randomized controlled clinical trial of patients with ARDS was implemented to study the impact of inhaled nitric oxide (inhNO) on lung function, morbidity, and mortality. Thirty patients with ARDS were randomly allocated to usual care or usual care plus inhNO. The optimal dose of inhNO was determined to be between 0.5 and 40 parts-per-million daily. All therapeutic interventions were standardized. ARDS resulted mainly from sepsis (25 of the 30). During the first 24 h, the hypoxia score increased greatly in patients treated with inhNO +70.4 mm Hg (+59%) versus +14.2 mm Hg (+9.3%) for the control group (p = 0.02), venous admixture decreased from 25.7 to 15.2% in the inhNO group, and from only 19.4 to 14.9% in the control group (p = 0.05). After the first day of therapy no further beneficial effect of inhNO was detected. Forty percent of the patients treated with inhNO were alive and weaned from mechanical ventilation within 30 d after randomization compared with 33.3% in the control group (p = 0.83). The 30-d mortality rate was similar in the two groups; most deaths (11 of 17) were due to multiple organ dysfunction syndrome. This study shows that inhNO, in this population, may improve gas exchange but does not affect mortality.

Never the same again. Family doctors' priorities challenged by ice storm

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Medical ethics during genocide

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Opening Pandora's box. Family physicians and alternative medicine

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Habits of death. Cultural variation in attitudes toward death

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