bluuebunny/crossref_metadata_2025_split huggingface dataset:
HFE mutations and risk of coronary heart disease in middle‐aged women
Authors: Van Der A D. L. , Peeters P. H. M. , Grobbee D. E. , Roest M. , Marx J. J. M. , Voorbij H. M. , Van Der Schouw Y. T. 
Published: September 2006

AbstractBackground  Although heterozygosity for the C282Y mutation in the HFE gene has been associated with an increased risk of cardiovascular events, epidemiological studies remain inconclusive. The aim of the present study was to obtain further evidence as to whether HFE mutations are associated with risk of coronary heart disease (CHD) in middle‐aged women. We used data of a cohort of 15 236 Dutch middle‐aged women to investigate whether C282Y carriers and H63D carriers are at increased risk of coronary heart disease compared with non‐carriers.Materials and methods  Women were included in the study between 1993 and 1997 and were followed until 1 January 2000 for cardiovascular events. HFE genotyping was performed on all 211 coronary heart disease cases and a randomly selected sample from the baseline cohort (n = 1526). A weighted Cox proportional hazards model was used to estimate crude, age‐adjusted and multivariate adjusted hazard ratios for C282Y and H63D carriership in relation to coronary heart disease.Results  Compared with non‐carriers, those that carried the C282Y allele were not at increased risk for CHD (HR = 1·25, 95% CI = 0·74–2·09). Neither did we find an association between the H63D mutation and CHD risk (HR = 0·73, 95% CI = 0·43–1·24).Conclusions  Our results are in accordance with similar studies to date, for which we present a meta‐analysis. HFE mutations appear not to affect the risk of coronary heart disease.
Inflammatory and endothelial markers in women with polycystic ovary syndrome
Authors: Diamanti‐Kandarakis E. , Alexandraki K. , Piperi C. , Protogerou A. , Katsikis I. , Paterakis T. , Lekakis J. , Panidis D. 
Published: September 2006

AbstractBackground  Women with polycystic ovary syndrome (PCOS) carry a pattern of cardiovascular risk factors. Endothelial dysfunction and chronic inflammation are early findings in the atherosclerotic process. The purpose of the study was to investigate the coexistence of active inflammation markers and endothelial dysfunction in young women with PCOS, and their relationship with metabolic and hormonal abnormalities of the syndrome.Materials and methods  Twenty‐five young women with PCOS and 25 controls of similar age and body mass index (BMI) were studied. Endothelial function was assessed by flow‐mediated dilatation (FMD) on the brachial artery and smooth muscle cells injury was excluded by nitrate‐induced dilatation (NID). Plasma levels of endothelin‐1 (ET‐1), soluble intercellular adhesion molecule‐1 (sICAM‐1), soluble vascular cell adhesion molecule‐1 (sVCAM‐1) and high sensitivity C‐reactive protein (hsCRP) were measured. Hormonal and metabolic profiles were determined in both groups.Results  Flow‐mediated dilatation (FMD) was statistically lower in PCOS (P < 0·001), whereas nitrate‐induced dilatation (NID) was similar within the two groups. Polycystic ovary syndrome (PCOS) had statistically higher levels of ET‐1 (P = 0·03), sICAM‐1 (P = 0·01), sVCAM‐1 (P = 0·02) and hsCRP (P = 0·01). Furthermore FMD was statistically higher in PCOS population with hsCRP 1 mg L−1 when compared with PCOS population with hsCRP > 1 mg L−1 (P = 0·02). Flow‐mediated dilatation (FMD) was negatively related to hsCRP (r = −0·512, P = 0·015); ET‐1 was positively related to free androgen index (r = 0·27, P = 0·05) and negatively to sex hormone‐binding globulin (r = −0·465, P = 0·022); sVCAM‐1 was positively related to total testosterone (r = 0·431, P = 0·036); hsCRP was positively related to BMI (r = 0·647, P = 0·001), and negatively related to FMD (r = −0·512, P = 0·015), quantitative insulin sensitivity check index (QUICKI) (r = −0·499, P = 0·018), and MATSUDA index (r = −0·445, P = 0·038).Conclusions  The present study demonstrates that endothelial dysfunction coexists and is influenced by the presence of increased serum levels of inflammation and endothelial activation markers in young women with PCOS. These parameters appear to be interrelated with hyperandrogenaemia in this insulin‐resistant population.
Effect of lactose on oro‐cecal transit in lactose digesters and maldigesters
Authors: He T. , Priebe M. G. , Welling G. W. , Vonk R. J. 
Published: September 2006

AbstractBackground  The transit time of the small intestine, in addition to lactase activity, may influence lactose digestion and thus play a role in the occurrence of lactose intolerance. The objectives of this study were to investigate the effect of lactose on the oro‐cecal transit time (OCTT) in lactose digesters and maldigesters as well as the possible mechanisms underlying these effects.Materials and methods  Twenty‐eight Chinese subjects and 16 Dutch subjects underwent one glucose and one lactose challenge in two single‐blinded tests. Twenty of the Chinese subjects without complaints after the challenge then underwent another lactose challenge. A 6‐h symptom score (SSC) was recorded, breath‐hydrogen concentration was measured and OCTT after consumption of glucose and lactose was determined with the lactose‐[13C] ureide breath test. The lactose digestion index (LDI) was determined in both the Dutch and 20 Chinese subjects with the 13C/2H‐glucose test.Results  Lactose digesters (n = 13) and maldigesters (n = 20) were classified based on the results of the LDI and the breath‐hydrogen test. The OCTT after the lactose and glucose challenges did not differ in the digesters, whereas in the maldigesters the OCTT, after the lactose challenge, was shorter than that after glucose. There was no difference in OCTT after the glucose challenge between the maldigesters and the digesters. However, the OCTT after the lactose challenge in the maldigesters was shorter than that in the digesters. The LDI of the digesters was significantly higher than that of the maldigesters. The OCTT after the lactose challenge was not correlated to the LDI in the maldigesters nor in the digesters. Based on the SSC after the one glucose and two lactose challenges, a tolerant (n = 7) and an intolerant (n = 5) group were classified in the Chinese subjects. The two groups did not differ in their LDI or OCTT after the lactose challenge. The OCTT after the lactose challenge was not correlated to the SSC or the LDI.Conclusions  Lactose triggers a faster oro‐cecal transit in lactose maldigesters, but not in digesters. However, this could not be explained by intestinal distension resulting from the osmotic load posed by maldigested lactose, and thus suggests a direct effect of lactose on intrinsic factors regulating intestinal motility.
Homocysteine, traditional risk factors and impaired renal function in coronary artery disease
Authors: Pizzolo F. , Friso S. , Olivieri O. , Martinelli N. , Bozzini C. , Guarini P. , Trabetti E. , Faccini G. , Corrocher R. , Girelli D. 
Published: September 2006

AbstractBackground  To establish whether the frequent finding of a moderate–intermediate increase in plasma total homocysteine (tHcy) causes coronary artery disease (CAD), the authors evaluated the number of coexisting major traditional risk factors, as well as the major tHcy determinants, in patients with the same degree of CAD but different tHcy levels.Materials and methods  The authors studied 180 patients with CAD, who were divided into three groups according to tHcy levels: 60 patients with normal tHcy, 60 patients with moderate (15–30 µmol L−1) and 60 patients with intermediate hyperhomocysteinaemia (30–100 µmol L−1). The patient groups were matched for gender, age and number of affected coronary vessels. All patients were checked for the presence of traditional risk factors for CAD (i.e. hypertension, diabetes, hyperlipidaemia, smoking habit, familial history, obesity), as well as determinants of tHcy levels. The population was subdivided into those having, or not, a substantial burden of traditional risk factors (i.e. < 4 and ≥ 4, respectively).Results  There was a significant trend towards a reduced number of subjects within the group with ≥ 4 risk factors across increasing tHcy levels (51·7%, 37·8%, 26%, for normal, moderate, intermediate tHcy, respectively, χ2 for linear‐trend = 0·006). Folate and vitamin B12 concentrations, estimated glomerular filtration rate (GFR), MTHFR 677C > T polymorphism were the major determinants of tHcy in this population.Conclusions  In patients with the same degree of CAD, those with hyperhomocysteinaemia had a reduced burden of traditional risk factors as compared with those with normal tHcy levels. Hyperhomocysteinaemia was significantly associated with an emerging non‐traditional risk factor such as lower GFR.
Combined LDI/SAT test to evaluate intestinal lactose digestion and mucosa permeability
Authors: Koetse H. A. , Klaassen D. , Van Der Molen A. R. H. , Elzinga H. , Bijsterveld K. , Boverhof R. , Stellaard F. 
Published: September 2006

AbstractBackground  Intestinal mucosal damage causes impaired digestive capacity and increased mucosal permeability. Quantification of damage can be used to improve treatment options. Currently, the Lactose Digestion Index (LDI) and the Sugar Absorption Test (SAT) are used for evaluation. The investigation studied whether both tests could be combined to provide a useful multifunctional test and whether measurements in blood (LDI) could be replaced by measurements in urine.Materials and methods  The LDI (25 g 13C‐lactose, 0·5 g 2H‐glucose), the SAT (5 g lactulose, 1 g L‐rhamnose) and the LDI/SAT combination test were performed in seven lactose‐digesting and eight lactose‐maldigesting adults. Plasma glucose 13C‐enrichment was determined by gas‐chromatography/combustion/isotope ratio mass‐spectrometry (GC/C/IRMS), 2H enrichment determined by gas‐chromatography/mass‐spectrometry (GC/MS) and urinary sugars by gas‐chromatography (GC).Results  The results of the separate LDI test were not different from those of the LDI/SAT in the lactose‐digester group (0·82 ± 0·06 vs. 0·81 ± 0·09), nor in the lactose‐maldigester group (0·36 ± 0·12 vs. 0·35 ± 0·06). A significant correlation was found between the 10‐h urinary‐lactose/lactulose ratio and the LDI (R2 = 0·71, P < 0·01). There were no differences in the lactulose/L‐rhamnose ratio between lactose‐digesters and lactose‐maldigesters using both the SAT and LDI/SAT tests.Conclusion  The LDI/SAT test is a reliable method of measuring digestion and permeability simultaneously. The 10‐h period urinary lactose/lactulose excretion ratio following lactose consumption reflects lactose digestive capacity.
Myostatin expression in ventricular myocardium in a rat model of volume‐overload heart failure
Authors: Shyu K. G. , Lu M. J. , Wang B. W. , Sun H. Y. , Chang H. 
Published: September 2006

AbstractBackground  Mechanical stress increases myocardial myostatin expression. However, the expression of myostatin in chronic heart failure resulting from volume‐overload and after treatment with β‐blockers is little known. The authors hypothesize that myostatin plays a role in the failing myocardium because of volume‐overload.Materials and methods  Aorto‐caval shunt was created over a 4‐week period in adult Sprague‐Dawley rats to induce volume‐overload heart failure.Results  Heart weight and body weight ratio significantly increased after shunting. The left ventricular end‐diastolic dimension also significantly increased. Treatment with carvedilol in the shunt group reversed the increase in heart weight and ventricular dimension to the baseline values. Myocardial and skeletal myostatin proteins were up‐regulated in the shunt group. The mRNA of myocardial myostatin also increased in the shunt group. Treatment with carvedilol reversed both protein and mRNA of myocardial myostatin to the baseline values. Treatment with N‐acetylcysteine and doxazosin partially decreased myostatin mRNA and protein expression as compared with the shunt group. Carvedilol normalized the increased immunohistochemical labelling of myocardial myostatin in the shunt group.Conclusion  Myocardial myostatin mRNA and protein expression were up‐regulated in the rat model of volume‐overload heart failure. Treatment with carvedilol is associated with a limitation of increased myostatin expression in the failing ventricular myocardium.
Stressors and coping of in‐hospital haemodialysis patients aged 65 years and over
Authors: Logan Susan M. , Pelletier‐Hibbert Maryse , Hodgins Marilyn 
Published: September 2006

Aims.  This paper reports a study to identify the types of stressors experienced by in‐hospital haemodialysis patients aged 65 years and older, and the use and perceived helpfulness of coping strategies to manage these stressors.Background.  Chronic renal failure and its treatments impose a variety of physical and psychosocial stressors, which challenge patients. Although the stressors and coping strategies of patients having dialysis treatment have been investigated, no study has specifically focused on older adults. Such investigation is important as the incidence of chronic kidney disease is increasing in this age group.Method.  In this descriptive, correlational study, the Haemodialysis Stressor Scale and Jalowiec Coping Scale were used to investigate stressors and coping strategies reported by 50 in‐hospital haemodialysis patients aged 65 years and older. The data were collected in Canada in 2004.Results.  Similar to previous research, the stressors of fatigue and fluid restrictions ranked highly as stressors in this sample. However, interference with social and recreational activities were stressors unique to this group. Findings challenge some common beliefs about haemodialysis patients. It is commonly believed that these patients ‘get used to’ haemodialysis, and therefore the number and troublesomeness of stressors decrease over time. This belief was not supported because length of time on haemodialysis did not affect participants’ appraisal of stressors. Another major finding was that older participants in this sample reported the use of fewer coping strategies and found them less helpful.Conclusion.  Further research is needed to investigate factors affecting the stressors and coping responses of older haemodialysis patients and to determine their impact on health outcomes. Such knowledge will assist nurses in developing age‐appropriate strategies for promoting optimum wellness for these patients who will likely spend the remainder of their life adhering to the regimen of haemodialysis.
Hope promoting strategies of Registered Nurses
Authors: Turner De Sales , Stokes Linda 
Published: September 2006

Aim. This paper describes self‐reported hope‐promoting strategies used by Registered Nurses whilst providing care for older patients in acute and long‐term care settings.Background. The literature is replete with claims that Registered Nurses engage in hope facilitation with their patients. However, these claims are largely conjecture, with few studies empirically identifying the extent to which Registered Nurses use hope interventions with their patients. Further, some authors have questioned whether nurses have the necessary skills to undertake this vital aspect of care.Methods. In this Gadamerian hermeneutic phenomenological study, undertaken in 2003 in Australia, we used in‐depth audiotaped interviews to collect data with 14 Registered Nurses. The interviews were transcribed verbatim and analysed using the Turner method.Findings. Whilst participants clearly reported that they engaged in hope facilitation with older patients, there were differences between the reported strategies used by Registered Nurses in acute and long‐term care settings. Further, the strategies reported were not unique to hope promotion and have been variously described in the literature on caring, presencing, holistic nursing and therapeutic nursing.Conclusion. It is clear that participants considered hope promotion to be a vital aspect of their care. However, the strategies that they reported were limited and not inclusive of many and varied suggestions emerging from published studies on hope promotion. Therefore, we recommend that nursing curricula, professional development and in‐service education programmes place hope facilitation on their agenda and foster a culture in which promoting hope is seen as a vital aspect of nursing care.
Heterosexual assumptions in verbal and non‐verbal communication in nursing
Authors: Röndahl Gerd , Innala Sune , Carlsson Marianne 
Published: September 2006

Aim.  This paper reports a study of what lesbian women and gay men had to say, as patients and as partners, about their experiences of nursing in hospital care, and what they regarded as important to communicate about homosexuality and nursing.Background.  The social life of heterosexual cultures is based on the assumption that all people are heterosexual, thereby making homosexuality socially invisible. Nurses may assume that all patients and significant others are heterosexual, and these heteronormative assumptions may lead to poor communication that affects nursing quality by leading nurses to ask the wrong questions and make incorrect judgements.Method.  A qualitative interview study was carried out in the spring of 2004. Seventeen women and 10 men ranging in age from 23 to 65 years from different parts of Sweden participated. They described 46 experiences as patients and 31 as partners.Findings.  Heteronormativity was communicated in waiting rooms, in patient documents and when registering for admission, and nursing staff sometimes showed perplexity when an informant deviated from this heteronormative assumption. Informants had often met nursing staff who showed fear of behaving incorrectly, which could lead to a sense of insecurity, thereby impeding further communication. As partners of gay patients, informants felt that they had to deal with heterosexual assumptions more than they did when they were patients, and the consequences were feelings of not being accepted as a ‘true’ relative, of exclusion and neglect. Almost all participants offered recommendations about how nursing staff could facilitate communication.Conclusion.  Heterosexual norms communicated unconsciously by nursing staff contribute to ambivalent attitudes and feelings of insecurity that prevent communication and easily lead to misconceptions. Educational and management interventions, as well as increased communication, could make gay people more visible and thereby encourage openness and awareness by hospital staff of the norms that they communicate through their language and behaviour.
Assessing the accuracy of species distribution models: prevalence, kappa and the true skill statistic (TSS)
Authors: ALLOUCHE OMRI , TSOAR ASAF , KADMON RONEN 
Published: September 2006

Summary

In recent years the use of species distribution models by ecologists and conservation managers has increased considerably, along with an awareness of the need to provide accuracy assessment for predictions of such models. The kappa statistic is the most widely used measure for the performance of models generating presence–absence predictions, but several studies have criticized it for being inherently dependent on prevalence, and argued that this dependency introduces statistical artefacts to estimates of predictive accuracy. This criticism has been supported recently by computer simulations showing that kappa responds to the prevalence of the modelled species in a unimodal fashion.
In this paper we provide a theoretical explanation for the observed dependence of kappa on prevalence, and introduce into ecology an alternative measure of accuracy, the true skill statistic (TSS), which corrects for this dependence while still keeping all the advantages of kappa. We also compare the responses of kappa and TSS to prevalence using empirical data, by modelling distribution patterns of 128 species of woody plant in Israel.
The theoretical analysis shows that kappa responds in a unimodal fashion to variation in prevalence and that the level of prevalence that maximizes kappa depends on the ratio between sensitivity (the proportion of correctly predicted presences) and specificity (the proportion of correctly predicted absences). In contrast, TSS is independent of prevalence.
When the two measures of accuracy were compared using empirical data, kappa showed a unimodal response to prevalence, in agreement with the theoretical analysis. TSS showed a decreasing linear response to prevalence, a result we interpret as reflecting true ecological phenomena rather than a statistical artefact. This interpretation is supported by the fact that a similar pattern was found for the area under the ROC curve, a measure known to be independent of prevalence.
Synthesis and applications. Our results provide theoretical and empirical evidence that kappa, one of the most widely used measures of model performance in ecology, has serious limitations that make it unsuitable for such applications. The alternative we suggest, TSS, compensates for the shortcomings of kappa while keeping all of its advantages. We therefore recommend the TSS as a simple and intuitive measure for the performance of species distribution models when predictions are expressed as presence–absence maps.
A revised model for lipid‐normalizing δ13C values from aquatic organisms, with implications for isotope mixing models
Authors: KILJUNEN MIKKO , GREY JONATHAN , SINISALO TUULA , HARROD CHRIS , IMMONEN HEMMO , JONES ROGER I. 
Published: September 2006

Summary

Stable isotope analyses coupled with mixing models are being used increasingly to evaluate ecological management issues and questions. Such applications of stable isotope analyses often require simultaneous carbon and nitrogen analyses from the same sample. Correction of the carbon isotope values to take account of the varying content of 13C‐depleted lipids is then frequently achieved by a lipid‐normalization procedure using a model describing the relationship between change in δ13C following lipid removal and the original C:N ratio of a sample.
We evaluated the applicability of two widely used normalization models using empirical data for muscle tissue from a wide range of fish and for aquatic invertebrates. Neither normalization model proved satisfactory, and we present some modifications that greatly improve the fit of one of the models to the fish muscle data. For invertebrates we found no clear relationship between change in δ13C following lipid removal and the original C:N ratio.
We also examined the effect of lipid‐normalization on the output of a mixing model designed to calculate the proportional contribution of prey items to the diet of a consumer. Mixing model output was greatly influenced by whether prey or consumer values alone or together were lipid‐normalized and we urge caution in the interpretation of results from these models pending further experimental evidence.
Synthesis and applications. We describe a revised lipid‐normalization model that should be applicable to a wide range of marine and freshwater fish species in studies applying stable isotope analyses to ecological management issues. However, we strongly advise against applying these kinds of lipid‐normalization models to aquatic invertebrate data. The interpretation of outputs from mixing models is greatly influenced by whether the carbon isotope data have been lipid‐normalized or not.