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PubMed1998

Privacy or help? The use of curtain positioning strategies within the maternity ward environment as a means of achieving and maintaining privacy, or as a form of signalling to peers and professionals in an attempt to seek information or support.

Midwives in the local maternity unit had noted that the interactions between women within the ward environment had started to decline. Women were spending long periods of time behind curtains drawn around their bed space. The staff hypothesized that this was because women desired the privacy of a single room. The literature review revealed a lack of understanding of the concept of privacy within a ward environment from a nursing or midwifery perspective. The review therefore, concentrated on the information offered by the fields of psychology and sociology. This study aimed to observe the methods women use to maintain or preserve their privacy within the ward environment. An ethnographic approach was used incorporating use of documentary evidence, participant observation and discussion, field maps and field notes. The findings of this study centred around the use of curtain positioning, subsequently referred to as 'signalling'. The strategies employed by women included complete closure for total withdrawal, semi-closure for seeking information or support, and partial closure of curtains around the individual's bed space for periods of solitude or rest. The findings have implications for both general and maternity hospital wards but in particular, wards within maternity units that incorporate women with mixed methods of infant feeding, or women in labour mixed with either postnatal or antenatal women.

Delivery Rooms↗

PubMed2006

Quantitative determination of piritramide in human plasma and urine by off- and on-line solid-phase extraction liquid chromatography coupled to tandem mass spectrometry.

A method for the liquid chromatography/tandem mass spectrometric (LC/MS/MS) quantification of piritramide, a synthetic opioid, in plasma after conventional off-line solid-phase extraction (SPE) and in urine by on-line SPE-LC/MS/MS in positive electrospray mode was developed and validated. Applicability of the on-line approach for plasma samples was also tested. Deuterated piritramide served as internal standard. For the off-line SPE plasma method mixed cation-exchange SPE cartridges and a 150 x 2 mm C18 column with isocratic elution were used. For the on-line SPE method, a Waters Oasis HLB extraction column and the same C18 analytical column in a column-switching set-up with gradient elution were utilized. All assays were linear within a range of 0.5-100 ng/mL with a limit of detection of 0.05 ng/mL. The intra- and interday coefficients of variance ranged from 1.3 to 6.1% for plasma and 0.5 to 6.4% for urine, respectively. The extraction recovery for the off-line plasma assay was between 90.7 and 100.0%. Influence of matrix effects, and freeze/thaw and long-term stability were validated for both approaches; influence of urine pH additionally for quantification in urine.

Blood Chemical Analysis↗

PubMed2026

Space to grieve and grow: A systematic review of psychosocial interventions for people newly diagnosed with multiple sclerosis.

OBJECTIVE: This systematic review synthesized evidence from intervention studies published over the past 25 years that aimed to improve coping and psychosocial well-being among individuals early in the multiple sclerosis (MS) disease course. The goal was to evaluate intervention characteristics, theoretical foundations, and psychosocial outcomes, and to identify gaps for future research. METHODS: Following PRISMA guidelines, a comprehensive search was conducted across PubMed, CINAHL, PsycINFO, and Web of Science (2000-2025). Eligible studies included quantitative or mixed-methods interventions that addressed coping or psychosocial well-being among adults newly diagnosed with MS. Data extraction and quality assessment were completed independently by multiple reviewers using the Joanna Briggs Institute Critical Appraisal Tools. RESULTS: Seven studies (n = 345) met inclusion criteria, representing cognitive-behavioral therapy, mindfulness, acceptance-based, and nurse- or peer-delivered interventions. The interval between diagnosis and intervention enrollment ranged from 14 days to >4 years, suggesting different phases of adjustment. All interventions produced significant short-term improvements in at least one psychosocial domain (e.g., anxiety, depression, stress, coping, or illness acceptance). However, sustained effects beyond 6-12 months were inconsistent. Common mechanisms across interventions included enhancing self-efficacy, stress management, and adaptive coping. CONCLUSIONS: The available evidence suggests that brief psychosocial interventions for adults in the early years after MS diagnosis are feasible and may provide short-term benefits for selected psychosocial outcomes. However, the evidence base remains limited, heterogeneous, and preliminary. Future studies should more clearly define diagnosis timing, use adequately powered designs and longer follow-up, and examine mechanisms of change.

Humans↗

PubMed1982

Effect of O2 affinity on arterial PO2 in animals with central vascular shunts.

Central vascular or intracardiac shunts result in venous admixture and reduced saturation of systemic arterial blood. This is pronounced in most species of amphibians and reptiles and may occur as congenital defects in homeotherms. A two-compartment model is useful to analyze the effects of shunt on O2 transport. The PO2 of a mixture of pulmonary (ideal) and mixed venous (shunt) blood will be a function of the resulting O2 saturation, analogous to the principle of the "mixing method" in vitro. Furthermore, for a given saturation, the PO2 of systemic arterial blood (PaO2) should be inversely related to the O2 affinity of the mixed blood. The present study tested this two-compartment model of shunt in animals with normally occurring right-to-left shunts (amphibians and reptiles) and with dogs having artificial shunts. The O2 dissociation curves (ODC) of the blood were manipulated by varying body temperature and blood pH. For any level of saturation of systemic arterial blood, the PaO2 was found to increase with factors that shifted the ODC to the right. This experimental support of mathematical models of shunting and PaO2 suggests that animals with intracardiac or central vascular shunts are benefited by low-O2-affinity blood, a condition that is common in amphibians and reptiles. For an individual ectothermic vertebrate, an increase in O2 demand due to increased body temperature would, because of decreased O2 affinity, be accompanied and perhaps facilitated by an increase in PaO2 if saturation remained constant.

Ambystoma↗

PubMedDate not supplied

Porosity in manually and machine mixed resin-modified glass ionomer cements.

The powder and liquid components of resin-modified glass ionomer cements are available in manual and machine mixed forms. This study quantified the effect mixing methods have on the porosity and shear strength of a resin-modified glass ionomer cement (RMGIC). A RMGIC (Fuji II LC) was manually or machined mixed according to manufacturer's instructions. Thin, disc-shaped specimens (n = 5) were made by compressing the cement between glass platens to a thickness of approximately 76 microns. The specimens were light cured for 120 seconds. Digital images of the specimens were recorded using a measuring microscope and slide film scanner. Digital imaging software was used to determine the number and volume of the cement's pores. Shear test specimens of manual and machine mixed cements (n = 10) of each group (approximately 800 microns thickness) were made as previously described. Shear punch tests were conducted using a 3.75 mm diameter punch mounted on a universal testing machine. The mean number and total volume of pores in the manually mixed specimens was considerably greater than that of the machine mixed group (p < 0.05). The shear punch test results of the machine mixed group was significantly higher than the manual mixed group, (p < 0.05).

Drug Compounding↗

PubMed2004

Providing more up-to-date estimates of patient survival: a comparison of standard survival analysis with period analysis using life-table methods and proportional hazards models.

OBJECTIVE: Standard survival methods can yield out-of-date estimates of long-term survival. Period analysis, based on life-table methodology, provides more up-to-date survival estimates by exploring survival during a restricted recent period of interest. It excludes the short-term survival of patients recruited at the start of the study. We use statistical models to further develop the method of period analysis, providing more up-to-date estimates of survival and the ability to explore differences in survival by covariates and adjust for case mix. METHODS: We use cancer registry data for colorectal cancer in Leicestershire, UK, to illustrate the use of Cox proportional hazards (CPH) models to estimate period and standard survival. We compare these estimates with those obtained using life-table methodology. RESULTS: Period estimates were slightly higher than the standard estimates as they reflect recent improvements in short-term survival. The results for period analysis using the life-table approach and using CPH models were similar. However, CPH models allowed further investigation of other risk factors and the ability to control for potential confounding variables. CONCLUSION: Using period survival estimates, more up-to-date information is available to clinicians and others with an interest in monitoring survival. Period CHP models offer all the advantages of statistical modeling, and are straightforward to fit in standard statistical packages.

Colorectal Neoplasms↗

PubMed2006

Contraceptive use, fertility, and unsafe abortion in developing countries.

OBJECTIVES: Despite a substantial rise in contraceptive use around the world, unplanned pregnancies and induced abortion continue to occur. Each year an estimated 19 million abortions are carried out outside the legal system, often by unskilled practitioners or under unhygienic conditions. This paper explores the relationship between contraceptive prevalence and unsafe abortion in developing regions with different levels of fertility. These relationships manifest the extent to which the desire to regulate fertility is addressed by contraception or by unsafe abortion, where access to safe abortion is legally restricted. METHODS: Secondary analysis of estimates of unsafe abortion, total fertility rate and contraceptive prevalence, by geographical regions. RESULTS: High levels of unsafe abortion persist even where contraceptive prevalence is increasing and fertility is declining. It appears that a high dependence on sterilization for limiting family size may by be preceded by reliance on unsafe abortion, where abortion is restricted, for birth spacing. CONCLUSIONS: The reliance on unsafe abortion could be reduced during fertility transition by improving women's access to reversible contraceptives for spacing births as well as to sterilization for terminating childbearing. Expanding contraceptive choices and a balanced method mix can serve as an effective strategy to prevent unsafe abortion where reliance on sterilization to limit childbearing is not preceded by the use of reversible modern methods for spacing and where access to safe abortion is restricted by law. The intriguing association between contraceptive method choice and the incidence of unsafe abortion deserves further exploration.

Abortion, Illegal↗

PubMed1995

Nitric oxide administration using constant-flow ventilation.

Nitric oxide (NO) gas is known as both a vasodilator and a toxin. It can react with oxygen to form compounds more toxic than itself, such as nitrogen dioxide (NO2). The reactions are time dependent; thus, infusing NO into breathing circuits as close to ventilated subjects as possible may help minimize toxic byproduct exposure. Unfortunately, flow rates commonly used with mechanical ventilation favor laminar gas flow (streaming) within the breathing circuits. Streaming could delay mixing of NO with other inhaled gases. This mixing delay may interfere with accurate monitoring and/or delivery of NO. We tested the hypothesis that streaming of NO infused by constant flow into the inspiratory limb of a constant-flow mechanical ventilation system can lead to NO concentration delivery estimate errors. We then compared the NO2 concentrations at the ventilator Y-piece with three different NO mixing methods: blending the gases before they reach the breathing circuit inspiratory limb, infusing NO directly into the breathing circuit inspiratory limb far enough from the Y-piece to ensure thorough mixing, and infusing NO directly into the breathing circuit inspiratory limb immediately before the gases reach an in-line mixing device placed close to the Y-piece. Our results indicate that streaming can lead to NO concentration delivery estimate errors and that these errors can be characterized by measuring NO concentration variations across the inspiratory tubing's luminal diameter. NO2 concentration measured at the ventilator Y-piece were dependent on NO concentrations (p < 0.0001), NO delivery methods (p < 0.0001), and interactions between NO concentrations and NO delivery methods (p < 0.0001). We conclude that gas streaming and toxic byproduct exposure should be considered together when choosing an NO delivery method.

Dose-Response Relationship, Drug↗

PubMed2006

Synthesis and characterization of mesoporous ceria/alumina nanocomposite materials via mixing of the corresponding ceria and alumina gel precursors.

Mesoporous ceria/alumina, CeO(2)/Al(2)O(3), composites containing 10, 20 and 30% (w/w) ceria were prepared by a novel gel mixing method. In the method, ceria gel (formed via hydrolysis of ammonium cerium(IV) nitrate by aqueous ammonium carbonate solution) and alumina gel (formed via controlled hydrolysis of aluminum tri-isopropoxide) were mixed together. The mixed gel was subjected to subsequent drying and calcination for 3 h at 400, 600, 800 and 1000 degrees C. The uncalcined (dried at 110 degrees C) and the calcined composites were investigated by different techniques including TGA, DSC, FTIR, XRD, SEM and nitrogen adsorption/desorption isotherms. Results indicated that composites calcined for 3 h at 800 degrees C mainly kept amorphous alumina structure and gamma-alumina formed only upon calcinations at 1000 degrees C. On the other hand, CeO(2) was found to crystallize in the common ceria, cerinite, phase and it kept this structure over the entire calcination range (400-1000 degrees C). Therefore, high surface areas, stable surface textures, and non-aggregated nano-sized ceria dispersions were obtained. A systematic texture change based on ceria ratio was observed, however in all cases mesoporous composite materials exposing thermally stable texture and structure were obtained. The presented method produces composite ceria/alumina materials that suit different applications in the field of catalysis and membranes technology, and throw some light on physicochemical factors that determine textural morphology and thermal stability of such important composite.

Journal Article↗

PubMed2005

'She gave it her best shot right away': patient experiences of biomedical and patient-centered communication.

OBJECTIVE: Medical educators and researchers recommend a patient-centered interviewing style, but little empirical data exists regarding what aspects of physician communication patients like and why. We investigated patient responses to videotaped doctor-patient vignettes to ascertain what they liked about patient-centered and biomedical communication. METHODS: We conducted semi-structured interviews with 230 adult medicine patients who viewed videotapes depicting both patient-centered and biomedical physician communication styles. We used a mixed methods approach to derive a "ground-up" framework of patient communication preferences. RESULTS: Respondents who preferred different communication styles articulated different sets of values, important physician behaviors, and physician-patient role expectations. Participants who preferred the patient-centered physician (69%) liked that she worked with and respected patients and explored what the patient wanted. Participants who preferred the biomedical physician (31%) liked that she prevented harm, demonstrated medical authority, and delivered information clearly. CONCLUSIONS: Patients like (and dislike) patient-centered communication for thoughtful, considered reasons that appear grounded in their values and expectations about physicians, patients, and the clinical encounter. PRACTICE IMPLICATIONS: Better understanding the diversity of patient communication preferences may lead to more effective and individualized care.

Adult↗

PubMed2001

Population mixing and childhood diabetes.

BACKGROUND: Exposure to infections, particularly in early life, may modify the risk of developing childhood diabetes. Population mixing, based on the number and diversity of incoming migrants to an area can be used as a proxy measure for exposure to infections. We tested the hypothesis that incidence of childhood Type 1 diabetes is higher in areas of low population mixing. METHODS: Children (<15 years) diagnosed with diabetes between 1986--1994 in Yorkshire, UK (n = 994) were analysed with demographic data and denominator populations from the 1991 UK Census. Population mixing was estimated separately for 'any age' (>1 year) and children (1--15 years) for each area, using the proportion of migrants and an index of diversity based on numbers and origins of migrants. Regression models calculated the effect of 'any age' and childhood population mixing on the incidence of diabetes, controlling for population density, ethnicity and proportion of migrants. RESULTS: Areas with low levels of population mixing of children (bottom decile), were significantly associated with higher incidence of childhood diabetes for 0-14 years (incidence rate ratio [IRR] = 1.46, 95% CI : 1.01--2.11). When stratified by age different effects were observed for childhood population mixing with raised IRR for ages 5-9 (2.23, 95% CI : 1.20--4.11) and 10-14 (1.47, 95% CI : 0.89--2.42), and decreased IRR for 0--4-year-olds (0.56, 95% CI : 0.17--1.82). CONCLUSION: The incidence of childhood diabetes is highest in areas where limited childhood population mixing occurs and the diversity of origins of incoming children is low; those over 4 years are at greatest risk. This is consistent with an infectious hypothesis where absence of stimulation to the developing immune system increases vulnerability to late infectious exposure, which may precipitate diabetes.

Adolescent↗

PubMed1998

Kinetic evidence for an obligatory intermediate in the folding of the membrane protein bacteriorhodopsin.

A photodiode array in conjunction with a rapid stopped-flow mixing method, with a millisecond time resolution, is used here to study the refolding of the membrane protein bacteriorhodopsin from an apoprotein state with a native-like secondary structure in mixed phospholipid/detergent micelles. Refolding to the native state is initiated by the rapid mixing of all-trans-retinal and the apoprotein bacterioopsin in mixed micelles. A lag phase of several seconds is observed in the appearance of the native state, as monitored by the increase in absorbance of the native chromophore. This observation demonstrates unequivocally that an intermediate is obligatory in the formation of bacteriorhodopsin. It is further shown that this intermediate is spectroscopically distinct from free retinal (absorbance maximum approximately 380 nm) and bacteriorhodopsin (absorbance maximum approximately 560 nm) and absorbs maximally at 430 nm. Evidence for the decay of the 430 nm intermediate into bacteriorhodopsin via three distinct parallel pathways is also provided. Taken together, these findings are used to describe a model in which distinct populations of the apoprotein in mixed micelles appear to fold along separate pathways via their corresponding intermediates into the native state. How the results of this study provide new insights into the mechanisms of protein folding is discussed.

Apoproteins↗

PubMed2001

Heteroresistance in Mycobacterium tuberculosis.

SETTING: Drug resistance in Mycobacterium tuberculosis is often linked to specific mutations in a limited number of resistance genes. Detection of these mutations in a cultured isolate can predict the resistant phenotype. Genotypic analysis of the mycobacteria directly in a clinical specimen would result in considerable time saving for resistance prediction. OBJECTIVE: To find out whether resistance-predicting genotypes of mycobacteria found after cultivation always give a good reflection of those in the original clinical sample. DESIGN: Restriction fragment length polymorphisms of repetitive polymerase chain reaction (PCR) amplification and cloning of PCR products were used as nonintegrative methods to describe the composition of katG, rpsL and embB genotypes involved in resistance to isoniazid, streptomycin and ethambutol, respectively, in the original sample. This result was then compared to the phenotypic resistance profile after cultivation. RESULTS: Using both methods, mixed, heteroresistant populations could be detected in almost every fifth analyzed sample (katG: 5 of 16; rpsL: 3 of 17; embB: 1 of 21). Direct sequencing, a widely used integrative method, repeatedly failed to detect heteroresistance. CONCLUSION: Heteroresistance is a valid phenomenon in clinical tuberculosis. It is not rare and not restricted to a particular resistance gene, and is obscured by cultivation as well as by some, not all, culture-independent resistance prediction tests.

Antitubercular Agents↗

PubMed2000

Morphology and immersion behavior of plasma-sprayed hydroxyapatite/bioactive glass coatings.

A series of hydroxyapatite/bioactive glass (HA/BG) coatings have been plasma-sprayed on Ti6Al-4V substrate using HA/BG powders that were prepared by both sinter-granulation and direct mixing methods. The morphology and immersion behavior of these coatings in a simulated body fluid (SBF) were investigated. The results showed that in-house fabricated BG and sinter-granulated HA powders were irregularly shaped and dense. When 5 wt % or more BG was added in HA, the powder became rough and porous. X-ray diffraction (XRD) patterns showed that the presence of BG enhanced the decomposition of HA structure during fabrication of the powders. Reasonably high bond strengths were obtained from all coatings. The granulated type HA/BG coatings showed no significant differences in bond strength from the mixed type HA/BG coatings. The plasma spray process itself and the presence of BG enhanced the decomposition of apatite. Surface morphology of all sinter-granulated type coatings was similar to that of monolithic HA coating, that was comprised of patches of smooth and shiny glassy film and irregularly-shaped particles on its surface. The dissolution depth of plasma-sprayed coatings immersed in SBF was largely dependent on the type and composition of the coating. Granulated type HA/BG coatings were much less dissolvable than monolithic HA or mixed type HA/BG coatings. It seems that the presently used granulation method for the preparation of HA/BG powders plays a predominant role in determining the dissolution behavior of the plasma-sprayed coatings.

Journal Article↗

PubMed2000

An exploration of the epistemological intricacies of using qualitative data to develop a quantitative measure of user views of health care.

Nurse researchers are increasingly combining qualitative and quantitative methods in order to understand more fully the world of research subjects. Qualitative data are often used to explore the subjective meanings behind survey responses and to develop quantitative measures and scales. Insights from qualitative data help researchers to design instruments which are more sensitive to respondents' meanings and interpretations. The aim of this paper is to highlight the epistemological and methodological complexities involved in this enterprise through drawing on our own experience of developing an instrument to examine person-centredness in health care from a qualitative study of dissatisfaction. The intricacies of this project relate to: epistemological continuity and inconsistency; research roles; reflexivity; confirmation; and completeness. Through discussing the literature around integrating methods, we suggest that researchers could be assisted in their attempts to develop conceptually sound quantitative measures by extending the concept of reflexivity (used in qualitative research) to the quantitative components of mixed method studies. This would aid conceptual clarity by making explicit the social, cultural, and political construction of knowledge, and would also encourage researchers to reflect upon the ethical and political consequences of their research.

Adolescent↗

PubMedDate not supplied

New knowledge for and about primary care: a view through the looking glass of the Annals of Family Medicine.

PURPOSE: At this second anniversary of the Annals of Family Medicine, we sought to characterize primary care research and to identify opportunities for new directions by analyzing the content of the first and second volumes of the Annals. METHODS: Using an a priori classification scheme, 2 editors independently categorized each research article and essay published in 2003 and 2004, excluding supplements. We categorized the domain of knowledge, methods, topical content, whether articles represented core values of primary care, and looked for articles that studied health/illness/symptoms from a uniquely primary care experience. We reconciled differences by discussion. RESULTS: Among 110 articles, knowledge domains reflected the 4 quadrants of the clinician (n = 6), patient, family, or community (10), health care system (32), disease (22), or the interface (39) between these quadrants. The most frequent methods were cross-sectional studies (23), cohorts (15), randomized clinical trials (13), qualitative interviews (11), analyses of secondary data (11), systematic reviews (11), methods/theory development (10), self-reflections (8), and mixed methods (5). The most common topical areas were chronic disease and prevention. Core primary care values were represented in 75% of articles. Only 2 articles represented an integrative illness/healing perspective. CONCLUSIONS: Despite contemporary forces driving a reductionistic approach, primary care research, as reflected by articles published in the Annals of Family Medicine, addresses the domains of knowledge that contribute to comprehensive, relationship-centered health care. More work is needed to understand the nature of health and illness in whole people and ways to integrate diverse knowledge, methods and fragmented health care.

Health Knowledge, Attitudes, Practice↗

PubMedDate not supplied

Enumeration of total coliforms and E. coli in foods by the SimPlate coliform and E. coli color indicator method and conventional culture methods: collaborative study.

The relative effectiveness of the SimPlate Coliform and E. coli Color Indicator (CEc-CI) method was compared to the AOAC 3-tube Most Probable Number (MPN) methods for enumerating and confirming coliforms and Escherichia coli in foods (966.23 and 966.24). In this study, test portions were prepared and analyzed according to the conditions stated in both the AOAC methods and SimPlate directions for use. Six food types were artificially contaminated with coliform bacteria and E. coli: frozen burritos, frozen broccoli, fluid pasteurized milk, whole almond nut meats, cheese, and powdered cake mix. Method comparisons were conducted. Overall, the SimPlate method demonstrated <0.3 log difference for total coliform and E. coli counts compared to the AOAC reference methods for the majority of food types and levels analyzed. In all cases, the repeatability and reproducibility of the SimPlate CEc-CI method were not different from those of the reference methods and in certain cases, were statistically better than those of the AOAC 3-tube MPN methods. These results indicate that the SimPlate CEc-CI method and the reference culture methods are comparable for enumeration of both total coliforms and E. coli in foods.

Colony Count, Microbial↗

PubMed1998

Fluorescence activated cell sorting: a reliable method in tissue engineering of a bioprosthetic heart valve.

BACKGROUND: Techniques of tissue engineering are used to seed human autologous cells in vitro on degradable mesh to create new functional tissue like a bioprosthetic heart valve. A precondition is subsequent seeding of native-valve-analogous pure endothelial and myofibroblast cell lines. The aim of this study is to find a safe method of isolating viable cell lines out of tissues from the operating room. METHODS: Mixed cells from ascending aorta obtained from the operating room were incubated with an endothelial-specific fluorescent marker. The labeled cells were activated and sorted by flow cytometry. Isolated cell lines were cultured and thereafter square sheets of polymeric scaffold were seeded with myofibroblasts, followed by endothelial cells. The created tissue was stained with hematoxylin and eosin, van Gieson stain, and stains for factor VIII and CD34. RESULTS: Control culture samples (n = 25) revealed vital uncontaminated endothelial and myofibroblast cell lines. Microscopy of the seeded meshes (n = 16) demonstrated a tissue-like structure. Van Gieson stain showed production of collagen. Endothelial cells formed a superficial monolayer, demonstrated by factor VIII and CD34; no invasive formation of capillaries was detectable. CONCLUSIONS: These results demonstrate that fluorescence activated cell sorting is a reliable and safe method to gain pure vital autologous cell lines out of human mixed cells for subsequent seeding on degradable mesh and that those cells are active to form new tissue.

Aorta↗