bluuebunny/crossref_metadata_2025_split huggingface dataset:
Long‐term mechanical ventilation in a critical care unit: existing in an uneveryday world
Authors: Johnson Patricia , St John Winsome , Moyle Wendy 
Published: February 2006

Aim.  This paper reports a study to describe and interpret the meaning of being on long‐term mechanical ventilation.Background.  Patients who require mechanical ventilation in a critical care unit for prolonged periods of time are typically sicker than those who are ventilated for shorter periods. Despite advances in treatment modalities for critically ill patients, many still require long‐term mechanical ventilation for 7 days or more. Therefore, caring for a long‐term ventilated patient is often an everyday occurrence for critical care nurses; however, there is insufficient evidence of the meaning of this experience from a patient perspective.Method.  We used an ontological phenomenological approach informed by the ideas of Heidegger. Data were collected using unstructured audio‐taped interviews with nine former patients from critical care units unit in Queensland, Australia. The data were collected between January 2000 and December 2001 and analysed thematically using the method developed by van Manen.Findings.  Thematic analysis revealed four themes. This paper presents the findings from the theme titled ‘existing in an uneveryday world’, which revealed what it meant for participants to exist, live through and survive the many physiological and psychological effects arising from their critical illness episode. For the most part, this was an unpleasant and frightening experience that involved bizarre nightmares and inability to distinguish time, place and the familiar body; disagreeable effects from the technology used and patient care activities; and reliance on external agents for survival. In addition, participants reported how they questioned their chances of surviving the critical illness ordeal.Conclusion.  There is a need for further research in the areas of sedative and analgesic management in critically ill patients, methods of communicating with intubated and mechanically ventilated patients, and debriefing and follow‐up support services for survivors.
Searching for meaning in negative events: concept analysis
Authors: Skaggs Brenda G. , Barron Cecilia R. 
Published: February 2006

Aim. The aim of this paper was to synthesize the literature related to meaning and present a conceptual analysis of searching for meaning in unexpected, significant, negative events.Background. Events or situations that are perceived as unexpected and negative (e.g. chronic and/or life‐threatening illness) can disrupt life plans and lead to emotional distress. Nurses are in a key position to aid in the coping process by assisting individuals to integrate the meaning of an unexpected, negative event into the life experience.Methods. In May 2004, a comprehensive literature search using the terms meaning, search for meaning, meaning‐making, making meaning, life change events, adaptation‐psychological, stress, and coping was carried out. Of 339 possible references, 86 were included in the analysis.Findings. Global meaning refers to an individual's beliefs, values, and purpose/goals. Situational meaning refers to the meaning the individual attaches to a situation. When the meaning attached to the situation is not congruent with global meaning, meaning is considered shattered and a search for meaning ensues. In the search for meaning, people may attempt to change the meaning of the event (through reattributions or creating illusions) or change global meaning (through positive reappraisal, problem‐solving coping, or revaluing ordinary events).Conclusion. Nurses are in a key position to assist people through negative events. The process of searching for meaning provides a solid foundation for the development of nursing interventions to assist individuals through difficult times. Research is needed to develop nursing interventions based on the process of the search for meaning, as well as measures reflective of the search for meaning.
Mosquito midguts and malaria: cell biology, compartmentalization and immunology
Authors: WHITTEN M. M. A. , SHIAO S. H. , LEVASHINA E. A. 
Published: February 2006

SUMMARY The malaria parasite Plasmodium has an absolute requirement for both a vertebrate and a mosquito host in order to complete its life cycle, and its interactions with the latter provide the focus for this review. The mosquito midgut represents one of the most challenging environments for the survival and development of Plasmodium, and is thus also one of the most attractive sites for novel targeted malaria control strategies. During their attempts to cross the midgut epithelium en route to the salivary glands, motile ookinetes are swiftly detected and labelled by mosquito recognition factors and targeted for destruction by a variety of immune responses that recruit killing factors both from the midgut and from other tissues in the surrounding body cavity. The exact interplay between these factors and the parasite is highly species‐ and strain‐specific, as are the timing and the route of parasite invasion. These features are paramount to determining the success of the infection and the vector competence of the mosquito. Here we discuss recent advances in genomic analyses, coupled with detailed microscopical investigations, which are helping to unravel the identity and roles of the major players of these complex systems.
The immunomodulatory factors of arthropod saliva and the potential for these factors to serve as vaccine targets to prevent pathogen transmission
Authors: TITUS R. G. , BISHOP J. V. , MEJIA J. S. 
Published: February 2006

SUMMARY In general, attempts to develop vaccines for pathogens transmitted by arthropods have met with little or no success. It has been widely observed that the saliva of arthropods that transmit disease enhances the infectivity of pathogens the arthropod transmits to the vertebrate host. Indeed, it has been observed that vaccinating against components of the saliva of arthropods or against antigens expressed in the gut of arthropods can protect the host from infection and decrease the viability of the arthropod. These results suggest that multi‐subunit vaccines that target the pathogen itself as well as arthropod salivary gland components and arthropod gut antigens may be the most effective at controlling arthropod‐borne pathogens as these vaccines would target several facets of the lifecycle of the pathogen. This review covers known immunomodulators in arthropod salivary glands, instances when arthropod saliva has been shown to enhance infection and a limited number of examples of antiarthropod vaccines, with emphasis on three arthropods: sandflies, mosquitoes and hard ticks.
Elimination of deleterious mutations in plastid genomes by gene conversion
Authors: Khakhlova Olga , Bock Ralph 
Published: February 2006

SummaryAsexual reproduction is believed to be detrimental, mainly because of the accumulation of deleterious mutations over time, a hypothesis known as Muller's ratchet. In seed plants, most asexually reproducing genetic systems are polyploid, with apomictic species (plants forming seeds without fertilization) as well as plastids and mitochondria providing prominent examples. Whether or not polyploidy helps asexual genetic systems to escape Muller's ratchet is unknown. Gene conversion, particularly when slightly biased, represents a potential mechanism that could allow asexual genetic systems to reduce their mutation load in a genome copy number‐dependent manner. However, direct experimental evidence for the operation of gene conversion between genome molecules to correct mutations is largely lacking. Here we describe an experimental system based on transgenic tobacco chloroplasts that allows us to analyze gene conversion events in higher plant plastid genomes. We provide evidence for gene conversion acting as a highly efficient mechanism by which the polyploid plastid genetic system can correct deleterious mutations and make one good genome out of two bad ones. Our finding that gene conversion can be biased may provide a molecular link between asexual reproduction, high genome copy numbers and low mutation rates.
Comparison of two different techniques of reperfusion in adult orthotopic liver transplantation
Authors: Gruttadauria Salvatore , Cintorino Davide , Musumeci Alfredo , Arcadipane Antonio , Burgio Gaetano , Clarizia Sergio , Piazza Tommaso , Spada Marco , Verzaro Roberto , Marsh James W. , Marcos Amadeo , Gridelli Bruno 
Published: February 2006

Abstract: The aim of this study was to determine the impact of two reperfusion techniques on the peri‐operative hemodynamic changes and early post‐operative graft function of adult patients undergoing orthotopic liver transplantation.Material and methods: From June 2003 to May 2004, 50 consecutive liver transplants were performed and divided into two groups: group A, 25 patients, portal vein flush with 500 cm3 of Ringer's lactate without vena caval venting. Group B, 25 patients, vena caval venting with no portal vein flush. Donor and recipient characteristics were similar in both groups. Sixty‐four different parameters were analyzed, and Pearson's χ2 test and t‐test were used for statistical analysis, p0.05.Results: One patient (4%) in group B experienced a post‐reperfusion syndrome (PRS). Pearson's χ2 test found a significant relationship between the analyzed parameters and the two different reperfusion techniques for 10 parameters (t‐test analysis showed a significant difference between the two groups in favor of group A).Conclusions: In our transplant center, portal vein flush without vena caval venting provided a lower incidence of hemodynamic changes in the peri‐operative period after liver transplantation and earlier recovery of the graft function.
Validation of a screening protocol for identifying low‐risk candidates with type 1 diabetes mellitus for kidney with or without pancreas transplantation
Authors: Ma Irene W.Y. , Valantine Hannah A. , Shibata Atsuko , Waskerwitz Jane , Dafoe Donald C. , Alfrey Edward J. , Tan Jane C. , Millan Maria , Busque Stephan , Scandling John D. 
Published: February 2006

Abstract: Background:Certain clinical risk factors are associated with significant coronary artery disease in kidney transplant candidates with diabetes mellitus. We sought to validate the use of a clinical algorithm in predicting post‐transplantation mortality in patients with type 1 diabetes. We also examined the prevalence of significant coronary lesions in high‐risk transplant candidates.Methods:All patients with type 1 diabetes evaluated between 1991 and 2001 for kidney with/without pancreas transplantation were classified as high‐risk based on the presence of any of the following risk factors: age ≥45 yr, smoking history ≥5 pack years, diabetes duration ≥25 yr or any ST–T segment abnormalities on electrocardiogram. Remaining patients were considered low risk. All high‐risk candidates were advised to undergo coronary angiography. The primary outcome of interest was all‐cause mortality post‐transplantation.Results:Eighty‐four high‐risk and 42 low‐risk patients were identified. Significant coronary artery stenosis was detected in 31 high‐risk candidates. Mean arterial pressure was a significant predictor of coronary stenosis (odds ratio 1.68; 95% confidence interval 1.14–2.46), adjusted for age, sex and duration of diabetes. In 75 candidates who underwent transplantation with median follow‐up of 47 months, the use of clinical risk factors predicted all eight deaths. No deaths occurred in low‐risk patients. A significant mortality difference was noted between the two risk groups (p=0.03).Conclusions:This clinical algorithm can identify patients with type 1 diabetes at risk for mortality after kidney with/without pancreas transplant. Patients without clinical risk factors can safely undergo transplantation without further cardiac evaluation.
Prediction of glomerular filtration rate in renal transplant recipients: cystatin C or Modification of Diet in Renal Disease equation?
Authors: Pöge Uwe , Gerhardt Thomas , Stoffel‐Wagner Birgit , Palmedo Holger , Klehr Hans‐Ulrich , Sauerbruch Tilman , Woitas Rainer P. 
Published: February 2006

Abstract: Background: To overcome disadvantages of serum creatinine two strategies have been suggested to identify patients with reduced glomerular filtration rate (GFR). On the one hand, the Modification of Diet in Renal Disease (MDRD) equation is now recommended to classify the stage of chronic kidney disease. On the other hand, cystatin C (Cys C) has been investigated in numerous studies, finding a higher sensitivity than creatinine in detecting diminished GFR. To date, no comparison of both strategies in patients after renal transplantation has been performed.Methods: One hundred and five consecutive renal transplant recipients underwent 99mTc‐DTPA – clearance measurement. Simultaneously, MDRD estimates were calculated and Cys C serum levels were determined. ROC analyses were performed at different decision points from 20 to 70 mL/min/1.73 m2.Results: Although the area under the curve did not differ significantly between MDRD and Cys C within the tested GFR range, the AUC for Cys C tended to be higher when GFR exceeded 55 mL/min/1.73 m2. A significantly higher diagnostic accuracy for Cys C compared with MDRD (p=0.045 at 65 mL/min/1.73 m2) was found when investigating the subgroup of patients with well‐functioning grafts (GFR>40 mL/min/1.73 m2).Conclusion: MDRD equation is equivalent to Cys C measurement in renal transplant recipients. As availability of MDRD is superior to Cys C, we recommend GFR estimation using the MDRD equation. Nevertheless, Cys C may serve as a confirmation test of high MDRD estimates in patients with well‐functioning grafts because of superior accuracy in these patients.
Characteristics of long‐term live‐donor pediatric renal transplant survivors: A single‐center experience
Authors: El‐Husseini Amr A. , Foda Mohamed A. , Osman Yasser M. , Sobh Mohamed A. 
Published: February 2006

Abstract: Objectives: To study the characteristics and the predictors of survival observed in our pediatric live‐donor renal transplant recipients with an allograft that functioned for more than 10 yr.Methods: One hundred fifteen children underwent renal transplantation between 1976 and 1995. Of these, 30 had functioning allografts for more than 10 yr (range, 11–18). The patients included 18 males and 12 females, with a mean age at transplantation of 13 yr (range, 5–18). Characteristics of the patients, data on graft survival, and determinants of outcome were obtained by reviewing all medical charts.Results: At most recent follow‐up (January 2005), the mean daily dose of azathioprine was 1.2 mg/kg (range, 1–2) and that of prednisone was 0.16 mg/kg (range, 0.1–0.2). Mean creatinine clearance was 72 mL/min per 1.73 m2 (range, 45–112). Acute rejection occurred in 14 (47%) patients. Seven patients had one episode, five had two episodes, and two had three episodes of acute rejection. Three patients (10%) developed malignancy. A substantial proportion of patients (44%) were short, with a height standard deviation score (SDS) less than −1.88, which is below the third percentile for age and gender. One quarter of the patients, more commonly the females, were obese. Other complications included osteoporosis in 16 (53%) patients, avascular bone necrosis in four (13%), post‐transplantation diabetes mellitus in three (10%), and hypertension in 18 (60%). Twelve (40%) patients were married and 27% had children post‐transplantation. The independent determinants of long‐term graft survival were acute rejection and post‐transplant hypertension.Conclusion: Despite good renal function, long‐term pediatric renal transplant survivors are at risk of significant morbidity. The determinants of long‐term graft survival are acute rejection and post‐transplant hypertension.
An Analysis of Inter‐Population Divergence in Visual Display Behavior of the Green Anole Lizard (Anolis carolinensis)
Authors: Bloch Natasha , Irschick Duncan J. 
Published: February 2006

AbstractVariation in habitat structure can profoundly affect the evolution of visual displays in animals. We compared the field display behavior of two populations of the green anole lizard (Anolis carolinensis) in Southern Louisiana. These two populations occupy habitats varying markedly in structure (clumped vs. continuous), ecological setting (urban vs. natural) and the degree of male competition and predation. We filmed 56 large adult male lizards during the active spring reproductive period and detected substantial divergence in display behavior between populations. We found that (1) relative dewlap areas did not differ significantly between populations, (2) Tulane anoles spent about twice as much time displaying compared with Good Hope field anoles, although the average display duration did not differ significantly between populations, and (3) the two populations differed significantly in the relative frequency of display types: lizards from the Tulane population used a higher proportion of A and B display types, whereas Good Hope Field anoles used C displays more often. Finally, we detected differences in other aspects of display behavior (use of display modifiers, volley length distributions). We suggest that these display differences may result from differences in green anole male density (three times higher at Tulane), combined with habitat differences (clumped vs. continuous).
Broken Copulatory Organs are Low‐Cost Adaptations to Sperm Competition in Redback Spiders
Authors: Snow Lindsay S. E. , Abdel‐Mesih Amal , Andrade Maydianne C. B. 
Published: February 2006

AbstractIn some spiders, a discrete portion of the male's copulatory organ (the apical sclerite) breaks off during copulation and remains in the female's reproductive tract. Apical sclerites may prevent insemination by rivals (sperm competition), stimulate females to favourably bias paternity (cryptic choice) or breakage may reflect sexual conflict over copulation duration with little direct effect on paternity. It has been assumed that any benefits of organ breakage are balanced by a large cost (male sterility) in species where males could otherwise mate multiply, but this has never been experimentally tested. We examined these ideas in the Australian redback spider (Latrodectus hasselti Thorell 1870, Araneae: Theridiidae), a species where males are functionally sterile after one normal mating. We experimentally removed sclerites and found males were able to mate, had similar copulation durations and transferred similar numbers of sperm as males with intact sclerites. Benefits of organ breakage were examined by forcing intact, rival males to inseminate the same or opposite reproductive tracts (female have paired, independent tracts in this taxon) and assessing paternity as a function of sclerite location. As predicted, apical sclerites were typically deposited at the entrance to the female's sperm storage organ, where they could physically block insemination by rivals. First male precedence was common when males inseminated the same tract and deposited sclerites at the entrance to the spermatheca, but not when sclerites were found elsewhere in the tract, or when rivals inseminated opposite tracts (where physically blocking rivals was impossible). Our data show that, in redbacks, copulatory organ breakage is not a side‐effect of sexual conflict, is unlikely to be a cue for cryptic female choice, but allows males to avoid sperm competition. Moreover, copulatory organ damage can have minimal reproductive cost for males, so assumptions of sterility after organ breakage are unjustified without supporting data.
Functionally Referential Alarm Calls in Tamarins (Saguinus fuscicollis and Saguinus mystax) – Evidence from Playback Experiments
Authors: Kirchhof Janna , Hammerschmidt Kurt 
Published: February 2006

AbstractStudies on primate vocalisation have revealed different types of alarm call systems ranging from graded signals based on response urgency to functionally referential alarm calls that elicit predator‐specific reactions. In addition, alarm call systems that include both highly specific and other more unspecific calls have been reported. There has been consistent discussion on the possible factors leading to the evolution of different alarm call systems, among which is the need of qualitatively different escape strategies. We studied the alarm calls of free‐ranging saddleback and moustached tamarins (Saguinus fuscicollis and Saguinus mystax) in northeast Peru. Both species have predator‐specific alarm calls and show specific non‐vocal reactions. In response to aerial predators, they look upwards and quickly move downwards, while in response to terrestrial predators, they look downwards and sometimes approach the predator. We conducted playback experiments to test if the predator‐specific reactions could be elicited in the absence of the predator by the tamarins’ alarm calls alone. We found that in response to aerial alarm call playbacks the subjects looked significantly longer upwards, and in response to terrestrial alarm call playbacks they looked significantly longer downwards. Thus, the tamarins reacted as if external referents, i.e. information about the predator type or the appropriate reaction, were encoded in the acoustic features of the calls. In addition, we found no differences in the responses of S. fuscicollis and S. mystax whether the alarm call stimulus was produced by a conspecific or a heterospecific caller. Furthermore, it seems that S. fuscicollis terrestrial alarm calls were less specific than either S. mystax terrestrial predator alarms or either species’ aerial predator alarms, but because of the small sample size it is difficult to draw a final conclusion.
Uncontested categories: the use of race and ethnicity variables in nursing research
Authors: Drevdahl Denise J. , Philips Debby A. , Taylor Janette Y. 
Published: February 2006

Classifying human beings according to race and ethnicity may seem straightforward to some but it, in fact, belies a difficult process. No standard procedure exists for categorizing according to race and ethnicity, calling into question the variables’ use in research. This article explores the use of race and ethnicity variables in the nursing research literature. Content analysis was conducted of a sample of 337 original research studies published in Nursing Research from the years 1952, 1955, and then every 5 years through to 2000. Of the 337 research articles reviewed, 167 mentioned race, ethnicity, or their 81 code words or phrases. Out of the 167 articles, 153 used race or ethnicity to describe the study sample, and 45 of the 167 articles included race or ethnicity as an element of data analysis. Throughout the sample, there was substantial inconsistency related to race and ethnicity categorization, meanings of the terms, and use of these variables. Specificity related to conceptual assumptions, definitions, and context was missing and, as a result, data interpretation and understanding are suspect. The integrity of nursing knowledge requires that nurse researchers recognize and address the difficulties inherent in using race and ethnicity in health research.