bluuebunny/crossref_metadata_2025 huggingface dataset:
Transcultural nursing: the relationship between individualist ideology and individualized mental health care
Authors: LEIGHTON K.
Published: February 2005

This article attempts to clarify and underpin the view that individualized mental health nursing is culture biased and politically instrumental, adding weight to the transcultural argument that mental health care should be more culture sensitive than is often the case within conventional UK settings. It examines the political history of individualist ideology, and then uses social conflict theory to explore the potentially counter‐therapeutic relationship of individualism and individualized nursing care in the UK mental health sector. The article challenges the widespread idea that individualized mental health nursing is ‘liberal’, ‘democratic’, ‘holistic’ and ‘scientific’, and in so doing extends the transcultural agenda to large scale infracultural differences within the UK population. It also explores the potential for policy change towards a more pluralistic service, and outlines some of the practical steps which may be taken to access alternative care approaches. It is a power analysis, which may be of transferable value to nurses in mental health care inpatient units where conventional individualized approaches are failing to reintegrate service users into the community. A glossary of terms is presented at the end of this article.
Appendix: a novel type of homeotic mutation affecting floral morphology
Authors: Broadhvest Jean , Daigle Nathalie , Martin Marilyn , Haughn George W. , Bernier François
Published: February 2005

A mutant with altered floral morphology, designated Appendix, was observed among the progeny of a regenerated transgenic tobacco (Nicotiana tabacum) plant. Appendix flowers had small outgrowths resembling pistils on the tips of fertile anthers. No Obvious morphological changes could be seen in any other part of the plant. A more careful analysis using histological methods and scanning electron microscopy revealed that the outgrowths were composed only of a style and a stigma and that these added organs can support pollen germination and pollen tube growth. Examination of anther ontogeny using scanning electron microscopy indicated that the anther style and stigma of the Appendix mutant developed from a small group of cells at the anther tip coincident with development of the carpel style and stigma. Genetic analysis indicated that this mutation is nuclear, recessive and linked to the ‘transferred DNA’ (T‐DNA) inserted during the generation of transgenic plants using Agrobacterium tumefaciens. The Appendix phenotype does not correspond to any of the other types of floral homeotic mutations that have been described so far.
Support needs of supply nurses in rural and remote Queensland
Authors: Fiore Steven , Souzani Sanam , D’Amore Rita , Behan Kieran , Cutts Christopher , La Caze Adam
Published: February 2005

Objective:  The aim of this report is to discuss a needs analysis conducted with rural and remote nurses in Queensland undertaking supply of medications in public hospitals without a pharmacist.

Design:  Survey questionnaire.

Methods:  A questionnaire was faxed to 65 Queensland Health rural and remote hospitals using supply nurses. It contained six closed questions regarding previously identified medication ‘supply’ issues, and three open questions to determine additional information.

Results:  Of the surveys, 42 (65%) were returned. Major areas of interest included a safety checklist for medication supply (90%, 38/42), more information on medication labelling requirements (83%, 35/42) and timing of medications with regard to food (86%, 36/42). Requirements for patient counselling, increased access to consumer medication information (CMI) (76%, 32/42), and resources regarding doses, indications, interactions and adverse effects also rated highly (73%, 31/42). Thirty‐three supply nurses highlighted at least one issue in the open questions: more information on the legal requirements of repackaging medications (39%, 13/42), increased access to CMI and counselling tools (36%, 12/42) and an efficient stock control system (30%, 10/42).

Conclusions:  This report highlights the need to broaden current support services available to nurses undertaking the supply of medications. It is vital that support programs, and the laws and guidelines related to supplying medications in rural and remote hospitals, support health care professionals providing quality use of medicines (QUM) and reflect the realities of rural and remote health care.
Faecal incontinence: an unrecognised epidemic in rural North Queensland? Results of a hospital‐based outpatient study
Authors: Ho Yik‐Hong , Muller Reinhold , Veitch Craig , Rane Ajay , Durrheim David
Published: February 2005

Objectives:  We explored the prevalence of faecal incontinence (FI) in a referral hospital outpatient population, to explore suspicions that FI is inadequately studied, underestimated and poorly appreciated in the rural North Queensland (NQ) community.

Design:  Prospective cross‐sectional study using a specifically designed questionnaire.

Setting:  The Townsville Hospital, a referral centre serving rural NQ.

Subjects:  A total of 435 consecutive patients attending the gynaecology (n = 261) and colorectal clinics (n = 174) between 31 January and 12 June 2003 were enrolled (participating proportion 96.5%).

Main outcome measures:  FI prevalence, severity, impact on patients’ lives, and risk factors.

Results:  The prevalence of FI in the study population (median age 53 years) was 20.7%. Amongst affected patients (n = 90) the median duration of FI was 2 years with more than half of those affected soiling themselves at least once a month. Many patients with FI (42%) reported feeling hopeless at least some of the time. Rectal prolapse, chronic constipation, psychiatric problems, colon disease, and urinary incontinence were all significantly associated with FI. A CART analysis revealed that many patients (45%) with urinary incontinence and chronic constipation also experienced FI.

Conclusions:  This FI prevalence in a clinical setting in NQ is, apart from nursing home studies, the highest reported in the literature. FI negatively impacted on affected persons’ lives. In patients presenting with urinary incontinence and chronic constipation, physicians should specifically enquire whether FI is also present. Definitive community studies to determine the scale of this ‘silent epidemic’ in northern Australia are now required.
Laparoscopic or trephine faecal diversion: is there a preferred approach and why?
Authors: Jugool S. , McKain E. S. , Swarnkar K. , Vellacott K. D. , Stephenson B. M.
Published: February 2005

Background  Faecal diversion is often indicated in perineal sepsis and in the palliation of advanced ano‐rectal malignancy. This can be performed open or laparoscopically. The aim of this study was to assess the outcome of these two approaches to stoma creation.

Methods  Prospective evaluation of laparoscopic or ‘trephine’ stoma creation in 49 consecutive unselected patients.

Results  Eighteen (37%) patients (median age 68 years) underwent a laparoscopic approach in which there were no conversions. One patient required a laparotomy for stoma mal‐orientation and there were two (11%) deaths. Thirty‐one patients (median age 70 years) had a trephine stoma formed with two (6%) conversions but no deaths. Thirteen (42%) of these patients had surgery performed under regional anaesthesia. There was no difference in the hospital stay between the two groups and at a mean follow‐up of 16 months, 20 (41%) patients had died mainly from disease progression.

Conclusion  Both approaches to faecal diversion give adequate results in the short term. Laparoscopic techniques should be reserved for fitter patients as a trephine stoma can be performed under regional anaesthesia.
Cardiovascular responses to external compression of human calf muscle vary during graded metaboreflex stimulation
Authors: Bell Martin P. D. , White Michael J.
Published: February 2005

This study investigated the cardiovascular response to a standard external muscle compression during concomitant muscle metaboreflex stimulation of varying intensity in human calf muscle. Eleven healthy male subjects (mean (s.d.) age, 26 (5.6) years; height, 177 (5) cm; weight, 74.3 (6.8) kg) were seated in an isometric dynamometer with the angle of the knee at 90 deg, and the angle of the ankle at 85 deg. After a 150‐s rest period, subjects were asked to either perform isometric plantar flexion at 20, 30, 40, 50, 60, 70 or 80% of previously determined maximum isometric contractile force (MVC) for 90 s, or to sit at rest for this period. A thigh cuff maintained circulatory occlusion throughout the exercise period and for 180 s post exercise. After 60 s of post‐exercise circulatory occlusion (PECO), a calf cuff was inflated to 300 mmHg for 60 s followed by a further 60 s of PECO alone after which the thigh cuff was deflated. During PECO the mean arterial pressure (MAP) increase from rest was dependent upon the preceding exercise intensity (P < 0.001). Compression elicited a further significant change in MAP, and the magnitude of this change from the PECO baseline was also dependent upon the preceding exercise intensity (P < 0.01). These results are compatible with activation of a metabolically sensitised population of mechanoreceptive afferents in human muscle during external compression.
Betamethasone effects on fetal sheep cerebral blood flow are not dependent on maturation of cerebrovascular system and pituitary–adrenal axis
Authors: Löhle Matthias , Müller Thomas , Wicher Carola , Roedel Marcus , Schubert Harald , Witte Otto W. , Nathanielsz Peter W. , Schwab Matthias
Published: February 2005

Synthetic glucocorticoids are administered to pregnant women in premature labour to accelerate fetal lung maturation at a time when fetal cerebrovascular and endocrine systems are maturing. Exposure to glucocorticoids at 0.8–0.9 of gestation increases peripheral and cerebrovascular resistance (CVR) in fetal sheep. We examined whether the increase of CVR and its adverse effect on cerebral blood flow (CBF) depend on the current level of maturation of the pituitary–adrenal axis and the cerebrovascular system. Using fluorescent microspheres, regional CBF was measured in 11 brain regions before and 24 h and 48 h after the start of 3.3 μg kg−1 h−1 betamethasone (n= 8) or vehicle (n= 7) infusions to fetal sheep at 0.73 of gestation. Hypercapnic challenges were performed before and 24 h after the onset of betamethasone exposure to examine betamethasone effects on cerebrovascular reactivity. Betamethasone exposure decreased CBF by approximately 40% in all brain regions after 24 h of infusion (P < 0.05). The decline in CBF was mediated by a CVR increase of 111 ± 16% in the cerebral cortex and 129 ± 29% in subcortical regions (P < 0.05). Hypercapnic cerebral vasodilatation and associated increase in CBF were blunted (P < 0.05). Fetal CBF recovered after 48 h of betamethasone administration. There were no differences in glucocorticoid induced CBF and CVR changes compared with our previous findings at 0.87 of gestation. We conclude that the cerebrovascular effects of antenatal glucocorticoids are independent of cerebrovascular maturation and preparturient increase in activity of the fetal pituitary–adrenal axis.
Left ventricular endocardial longitudinal and transverse changes during isovolumic contraction and relaxation: a challenge
Authors: Goetz Wolfgang A. , Lansac Emmanuel , Lim Hou-Sen , Weber Patricia A. , Duran Carlos M. G.
Published: February 2005

Left ventricular (LV) longitudinal and transverse geometric changes during isovolumic contraction and relaxation are still controversial. This confusion is compounded by traditional definitions of these phases of the cardiac cycle. High-resolution sonomicrometry studies might clarify these issues. Crystals were implanted in six sheep at the LV apex, fibrous trigones, lateral and posterior mitral annulus, base of the aortic right coronary sinus, anterior and septal endocardial wall, papillary muscle tips, and edge of the anterior and posterior mitral leaflets. Changes in distances were time related to LV and aortic pressures and to mitral valve opening. At the beginning of isovolumic contraction, while the mitral valve was still open, the LV endocardial transverse diameter started to shorten while the endocardial longitudinal diameter increased. During isovolumic relaxation, while the mitral valve was closed, LV transverse diameter started to increase while the longitudinal diameter continued to decrease. These findings are inconsistent with the classic definitions of the phases of the cardiac cycle.
Retinal arteriolar diameter, blood velocity, and blood flow response to an isocapnic hyperoxic provocation
Authors: Gilmore Edward D. , Hudson Chris , Preiss David , Fisher Joe
Published: February 2005

The aim of this study was to simultaneously quantify the magnitude and response characteristics of retinal arteriolar diameter and blood velocity induced by an isocapnic hyperoxic provocation in a group of clinically normal subjects. The sample comprised 10 subjects (mean age, 25 yr; range, 21–40 yr). Subjects initially breathed air for 5–10 min, then breathed O2 for 20 min, and then air for a final 10-min period via a sequential rebreathing circuit (Hi-Ox; Viasys) to maintain isocapnia. Retinal arteriolar diameter and blood velocity measurements were simultaneously acquired with a Canon laser blood flowmeter (CLBF-100). The response magnitude, time, and lag of diameter and velocity were calculated. In response to hyperoxic provocation, retinal diameter was reduced from control values of 111.6 (SD 13.1) to 99.8 (SD 10.6; P < 0.001) μm and recovered after withdrawal of hyperoxia. Retinal blood velocity and flow concomitantly declined from control values of 32.2 (SD 6.4) mm/s and 9.4 (SD 2.5) μl/min to 20.7 (SD 3.4) mm/s and 5.1 (SD 1.3) μl/min, respectively ( P < 0.001 for both velocity and flow), and recovered after withdrawal of hyperoxia. The response times and response lags were not significantly different for each parameter between effect and recovery or between diameter and velocity. We conclude that arteriolar retinal vascular reactivity to hyperoxic provocation is rapid with a maximal vasoconstrictive effect occurring within a maximum of 4 min. Although there was a trend for diameter to respond before velocity to the isocapnic hyperoxic provocation, the response characteristics were not significantly different between diameter and velocity.
Comparative effects of single- and linear triple-site rapid bipolar pacing on atrial activation in canine models
Authors: Ryu Kyungmoo , Ghanem Raja N. , Khrestian Celeen M. , Matsumoto Naomichi , Goldstein Robert N. , Sahadevan Jayakumar , Dorostkar Parvin C. , Waldo Albert L.
Published: February 2005

Nonuniform conduction may cause block and/or delay, thereby providing a substrate for the onset and maintenance of reentrant atrial arrhythmias. We tested the hypothesis that linear triple-site, bipolar, rapid pacing (LTSBRP) of the right atrium generates more uniform wave-front propagation compared with single-site, bipolar, rapid pacing (SSBRP), thereby reducing and/or eliminating conduction block and delay that is otherwise present. Five dogs with pericarditis and three normal dogs were studied. Three plunge-wire electrode pairs were placed 5–7 mm apart in both perpendicular and parallel configurations at the superior aspect of the crista terminalis and were used to pace at 200- and 300-ms cycle lengths for ≤6 s. During pacing, 380 electrograms were recorded simultaneously from electrode arrays placed epicardially on the atria, which produced activation sequence maps for each pacing episode. Local conduction-velocity vectors were computed for each site during each episode. Histograms of absolute velocity vector angles from the x-axis (of the crista terminalis) were plotted to assess uniformity of wave-front propagation, and the magnitude of each vector was computed to assess the local speed. LTSBRP showed 1) more uniform linear activation wave fronts compared with SSBRP, 2) velocity vectors with a more uniform magnitude and direction compared with SSBRP, 3) a predominant absolute velocity vector angle vs. a scattered angle distribution with SSBRP, and 4) shorter right atrial activation time and faster mean epicardial speed than SSBRP for each pacing cycle length. LTSBRP created a more uniform wave-front propagation with less or no conduction block and/or delay compared with SSBRP.
Inhibition of hypoxic pulmonary vasoconstriction by antagonists of store-operated Ca2+ and nonselective cation channels
Authors: Weigand Letitia , Foxson Joshua , Wang Jian , Shimoda Larissa A. , Sylvester J. T.
Published: February 2005

Previous studies indicated that acute hypoxia increased intracellular Ca2+ concentration ([Ca2+]i), Ca2+ influx, and capacitative Ca2+ entry (CCE) through store-operated Ca2+ channels (SOCC) in smooth muscle cells from distal pulmonary arteries (PASMC), which are thought to be a major locus of hypoxic pulmonary vasoconstriction (HPV). Moreover, these effects were blocked by Ca2+-free conditions and antagonists of SOCC and nonselective cation channels (NSCC). To test the hypothesis that in vivo HPV requires CCE, we measured the effects of SOCC/NSCC antagonists (SKF-96365, NiCl2, and LaCl3) on pulmonary arterial pressor responses to 2% O2 and high-KCl concentrations in isolated rat lungs. At concentrations that blocked CCE and [Ca2+]i responses to hypoxia in PASMC, SKF-96365 and NiCl2 prevented and reversed HPV but did not alter pressor responses to KCl. At 10 μM, LaCl3 had similar effects, but higher concentrations (30 and 100 μM) caused vasoconstriction during normoxia and potentiated HPV, indicating actions other than SOCC blockade. Ca2+-free perfusate and the voltage-operated Ca2+ channel (VOCC) antagonist nifedipine were potent inhibitors of pressor responses to both hypoxia and KCl. We conclude that HPV required influx of Ca2+ through both SOCC and VOCC. This dual requirement and virtual abolition of HPV by either SOCC or VOCC antagonists suggests that neither channel provided enough Ca2+ on its own to trigger PASMC contraction and/or that during hypoxia, SOCC-dependent depolarization caused secondary activation of VOCC.
Attenuation of aortic baroreflex responses by microinjections of endomorphin-2 into the rostral ventrolateral medullary pressor area of the rat
Authors: Kasamatsu Ken , Sapru Hreday N.
Published: February 2005

The presence of μ-opioid receptors and endomorphins has been demonstrated in the general area encompassing the rostral ventrolateral medullary pressor area (RVLM). This investigation was carried out to test the hypothesis that endomorphins in the RVLM may have a modulatory role in regulating cardiovascular function. Blood pressure and heart rate (HR) were recorded in urethane-anesthetized male Wistar rats. Unilateral microinjections of endomorphin-2 (0.0125–0.5 mmol/l) into the RVLM elicited decreases in mean arterial pressure (16–30 mmHg) and HR (12–36 beats/min), which lasted for 2–4 min. Bradycardia was not vagally mediated. The effects of endomorphin-2 were mediated via μ-opioid receptors because prior microinjections of naloxonazine (1 mmol/l) abolished these responses; the blocking effect of naloxonazine lasted for 15–20 min. Unilateral stimulations of aortic nerve for 30 s (at frequencies of 5, 10, and 25 pulses/s; each pulse 0.5 V and 1-ms duration) elicited depressor and bradycardic responses. These responses were significantly attenuated by microinjections of endomorphin-2 (0.2 and 0.4 mmol/l). The inhibitory effect of endomorphin-2 on baroreflex responses was prevented by prior microinjections of naloxonazine. Microinjections of naloxonazine alone did not affect either baseline blood pressure and HR or baroreflex responses. These results indicate that endomorphin-2 elicits depressor and bradycardic responses and inhibits baroreflex function when injected into the RVLM. These effects are consistent with the known hyperpolarizing effect of opioid peptides on RVLM neurons.
Catullus 63 In a Roman Context
Authors: Nauta Ruurd
Published: February 2005

In this paper,1) Catullus' intentions in writing the Attis poem and his possible use of a Greek model are deliberately left out of account. Instead, the focus is on the meaning his poem may have had for his contemporary audience. Attis is a gallus, a castrated devotee of the Mater Magna, and thus a reconstruction is attempted of the mental picture that Romans of Catullus' time had of galli. Special importance is given to Lucretius' excursus on the Mater Magna, and his interpretation of castration as a punishment for lack of pietas. Finally, a slightly later source, Vergil's Aeneid, is used to suggest that Catullus' poem may also have been read as participating in a discourse about Roman national identity.
The Effect of the Echo. A Text Linguistic Approach to Catullus Carmen 63
Authors: Kroon Caroline
Published: February 2005

A text linguistic analysis of the narrative structure of Catullus 63 attempts, in the first half of this paper, to provide a better insight into the extraordinary nature of this poem as a narrative. On the basis of this analysis it is observed that the 'narrative event structure' is in fact subservient to what is called the 'thematic structure' of the poem, in which the devices of contrast and repetition play an essential role. The second half of the article elaborates on the all-pervasive use of repetition in the poem and the implications of this observation for its interpretation, leading up to the conclusion that in Catullus 63 repetition is a theme (or aim) in itself.
Ontological visualization of protein-protein interactions
Authors: Drabkin Harold J , Hollenbeck Christopher , Hill David P , Blake Judith A
Published: February 2005

Background

Cellular processes require the interaction of many proteins across several cellular compartments. Determining the collective network of such interactions is an important aspect of understanding the role and regulation of individual proteins. The Gene Ontology (GO) is used by model organism databases and other bioinformatics resources to provide functional annotation of proteins. The annotation process provides a mechanism to document the binding of one protein with another. We have constructed protein interaction networks for mouse proteins utilizing the information encoded in the GO annotations. The work reported here presents a methodology for integrating and visualizing information on protein-protein interactions.

Results

GO annotation at Mouse Genome Informatics (MGI) captures 1318 curated, documented interactions. These include 129 binary interactions and 125 interaction involving three or more gene products. Three networks involve over 30 partners, the largest involving 109 proteins. Several tools are available at MGI to visualize and analyze these data.

Conclusions

Curators at the MGI database annotate protein-protein interaction data from experimental reports from the literature. Integration of these data with the other types of data curated at MGI places protein binding data into the larger context of mouse biology and facilitates the generation of new biological hypotheses based on physical interactions among gene products.
A note on generalized Genome Scan Meta-Analysis statistics
Authors: Koziol James A , Feng Anne C
Published: February 2005

Background

Wise et al. introduced a rank-based statistical technique for meta-analysis of genome scans, the Genome Scan Meta-Analysis (GSMA) method. Levinson et al. recently described two generalizations of the GSMA statistic: (i) a weighted version of the GSMA statistic, so that different studies could be ascribed different weights for analysis; and (ii) an order statistic approach, reflecting the fact that a GSMA statistic can be computed for each chromosomal region or bin width across the various genome scan studies.

Results

We provide an Edgeworth approximation to the null distribution of the weighted GSMA statistic, and, we examine the limiting distribution of the GSMA statistics under the order statistic formulation, and quantify the relevance of the pairwise correlations of the GSMA statistics across different bins on this limiting distribution. We also remark on aggregate criteria and multiple testing for determining significance of GSMA results.

Conclusion

Theoretical considerations detailed herein can lead to clarification and simplification of testing criteria for generalizations of the GSMA statistic.
Evaluation of an education and activation programme to prevent chronic shoulder complaints: design of an RCT [ISRCTN71777817]
Authors: Bruijn Camiel De , de Bie Rob , Geraets Jacques , Goossens Marielle , Köke Albère , van den Heuvel Wim , van der Heijden Geert , Dinant Geert-Jan
Published: February 2005

Background

About half of all newly presented episodes of shoulder complaints (SC) in general practice are reported to last for at least six months. Early interventions aimed at the psychological and social determinants of SC are not common in general practice, although such interventions might prevent the development of chronic SC.

The Education and Activation Programme (EAP) consists of an educational part and a time-contingent activation part. The aim of the EAP is to provide patients with the proper cognitions by means of education, and to stimulate adequate behaviour through advice on activities of daily living.

Design

The article describes the design of a randomised clinical trial (RCT) to evaluate the effectiveness and cost-effectiveness of an EAP in addition to usual care, compared to usual care only, in the prevention of chronic SC after six months. It also describes the analysis of the cost and effect balance. Patients suffering from SC for less than three months are recruited in general practice and through open recruitment. A trained general practitioner or a trained therapist administers the EAP.

Primary outcome measures are patient-perceived recovery, measured by self-assessment on a seven-point scale, and functional limitations in activities of daily living. Questionnaires are used to study baseline measures, prognostic measures, process measures and outcome measures.

Discussion

The inclusion of patients in the study lasted until December 31st 2003. Data collection is to end in June 2004.
Treatment of osteoporosis in an older home care population
Authors: Vik Shelly A , Maxwell Colleen J , Hanley David A
Published: February 2005

Background

Previous research indicates that many patients with fractures indicative of underlying osteoporosis are not receiving appropriate diagnostic follow-up and therapy. We assessed osteoporosis treatment coverage in older home care clients with a diagnosis of osteoporosis and/or prevalent fracture.

Methods

Subjects included 330 home care clients, aged 65+, participating in a longitudinal study of medication adherence and health-related outcomes. Data on clients' demographic, health and functional status and service utilization patterns were collected using the Minimum Data Set for Home Care (MDS-HC). A medication review included prescribed and over-the-counter medications taken in the past 7 days. Criteria for indications for osteoporosis therapy included diagnosis of osteoporosis or a recent fracture. Coverage for treatment was examined for anti-osteoporotic therapies approved for use in 2000.

Results

Of the 330 home care clients, 78 (24%) had a diagnosis of osteoporosis (n = 47) and/or had sustained a recent fracture (n = 34). Drug data were available for 77/78 subjects. Among the subjects with osteoporosis or a recent fracture, 45.5% were receiving treatment for osteoporosis; 14% were receiving only calcium and vitamin D, and an additional 31% were receiving drug therapy (bisphosphonate or hormone replacement therapy). The remaining 54.5% of subjects were not receiving any approved osteoporosis therapy.

Conclusions

The high prevalence of undertreatment among a population of older adults with relatively high access to health care services raises concern regarding the adequacy of diagnosis and treatment of osteoporosis in the community.
The case for well-conducted experiments to validate statistical protocols for 2D gels: different pre-processing = different lists of significant proteins
Authors: Meleth Sreelatha , Deshane Jessy , Kim Helen
Published: February 2005

Background

The proteomics literature has seen a proliferation of publications that seek to apply the rapidly improving technology of 2D gels to study various biological systems. However, there is a dearth of systematic studies that have investigated appropriate statistical approaches to analyse the data from these experiments.

Results

Comparison of the effects of statistical pre-processing on the results of two sample t-tests suggests that the results of 2D gel experiments and by extension the conclusions derived from these experiments are not independent of the statistical protocol used.

Conclusions

This study suggests that there is a need for well-conducted validation studies to establish optimal statistical techniques to be used on such data sets.
Life history traits in selfing versus outcrossing annuals: exploring the 'time-limitation' hypothesis for the fitness benefit of self-pollination
Authors: Snell Rebecca , Aarssen Lonnie W
Published: February 2005

Background

Most self-pollinating plants are annuals. According to the 'time-limitation' hypothesis, this association between selfing and the annual life cycle has evolved as a consequence of strong r-selection, involving severe time-limitation for completing the life cycle. Under this model, selection from frequent density-independent mortality in ephemeral habitats minimizes time to flower maturation, with selfing as a trade-off, and / or selection minimizes the time between flower maturation and ovule fertilization, in which case selfing has a direct fitness benefit. Predictions arising from this hypothesis were evaluated using phylogenetically-independent contrasts of several life history traits in predominantly selfing versus outcrossing annuals from a data base of 118 species distributed across 14 families. Data for life history traits specifically related to maturation and pollination times were obtained by monitoring the start and completion of different stages of reproductive development in a greenhouse study of selfing and outcrossing annuals from an unbiased sample of 25 species involving five pair-wise family comparisons and four pair-wise genus comparisons.

Results

Selfing annuals in general had significantly shorter plant heights, smaller flowers, shorter bud development times, shorter flower longevity and smaller seed sizes compared with their outcrossing annual relatives. Age at first flower did not differ significantly between selfing and outcrossing annuals.

Conclusions

This is the first multi-species study to report these general life-history differences between selfers and outcrossers among annuals exclusively. The results are all explained more parsimoniously by selection associated with time-limitation than by selection associated with pollinator/mate limitation. The shorter bud development time reported here for selfing annuals is predicted explicitly by the time-limitation hypothesis for the fitness benefit of selfing (and not by the alternative 'reproductive assurance' hypothesis associated with pollinator/mate limitation). Support for the time-limitation hypothesis is also evident from published surveys: whereas selfers and outcrossers are about equally represented among annual species as a whole, selfers occur in much higher frequencies among the annual species found in two of the most severely time-limited habitats where flowering plants grow – deserts and cultivated habitats.
The small heat-shock proteins IbpA and IbpB reduce the stress load of recombinant Escherichia coli and delay degradation of inclusion bodies
Authors: LeThanh Ha , Neubauer Peter , Hoffmann Frank
Published: February 2005

Background

The permanently impaired protein folding during recombinant protein production resembles the stress encountered at extreme temperatures, under which condition the putative holding chaperones, IbpA/IbpB, play an important role. We evaluated the impact of ibpAB deletion or overexpression on stress responses and the inclusion body metabolism during production of yeast α-glucosidase in Escherichia coli.

Results

Deletion of ibpAB, which is innocuous under physiological conditions, impaired culture growth during α-glucosidase production. At higher temperatures, accumulation of stress proteins including disaggregation chaperones (DnaK and ClpB) and components of the RNA degradosome, enolase and PNP, was intensified. Overexpression of ibpAB, conversely, suppressed the heat-shock response under these conditions. Inclusion bodies of α-glucosidase started to disaggregate after arrest of protein synthesis in a ClpB and DnaK dependent manner, followed by degradation or reactivation. IbpA/IbpB decelerated disaggregation and degradation at higher temperatures, but did hardly influence the disaggregation kinetics at 15°C. Overexpression of ibpAB concomitant to production at 42°C increased the yield of α-glucosidase activity during reactivation.

Conclusions

IbpA/IbpB attenuate the accumulation of stress proteins, and – at high temperatures – save disaggregated proteins from degradation, at the cost, however, of delayed removal of aggregates. Without ibpAB, inclusion body removal is faster, but cells encounter more intense stress and growth impairment. IbpA/IbpB thus exert a major function in cell protection during stressful situations.
Passive and active ventricular elastances of the left ventricle
Authors: Zhong Liang , Ghista Dhanjoo N , Ng Eddie YK , Lim Soo T
Published: February 2005

Background

Description of the heart as a pump has been dominated by models based on elastance and compliance. Here, we are presenting a somewhat new concept of time-varying passive and active elastance. The mathematical basis of time-varying elastance of the ventricle is presented. We have defined elastance in terms of the relationship between ventricular pressure and volume, as: dP = EdV + VdE, where E includes passive (Ep) and active (Ea) elastance. By incorporating this concept in left ventricular (LV) models to simulate filling and systolic phases, we have obtained the time-varying expression for Ea and the LV-volume dependent expression for Ep.

Methods and Results

Using the patient's catheterization-ventriculogram data, the values of passive and active elastance are computed. Ea is expressed as: "Equation missing"; Epis represented as: "Equation missing". Ea is deemed to represent a measure of LV contractility. Hence, Peak dP/dt and ejection fraction (EF) are computed from the monitored data and used as the traditional measures of LV contractility. When our computed peak active elastance (Ea,max) is compared against these traditional indices by linear regression, a high degree of correlation is obtained. As regards Ep, it constitutes a volume-dependent stiffness property of the LV, and is deemed to represent resistance-to-filling.

Conclusions

Passive and active ventricular elastance formulae can be evaluated from a single-beat P-V data by means of a simple-to-apply LV model. The active elastance (Ea) can be used to characterize the ventricle's contractile state, while passive elastance (Ep) can represent a measure of resistance-to-filling.
FADD adaptor in cancer
Authors: Tourneur Léa , Buzyn Agnès , Chiocchia Gilles
Published: February 2005

FADD (Fas Associated protein with Death Domain) is a key adaptor molecule transmitting the death signal mediated by death receptors. In addition, this multiple functional protein is implicated in survival/proliferation and cell cycle progression. FADD functions are regulated via cellular sublocalization, protein phosphorylation, and inhibitory molecules. In the present review, we focus on the role of the FADD adaptor in cancer. Increasing evidence shows that defects in FADD protein expression are associated with tumor progression both in mice and humans. Better knowledge of the mechanisms leading to regulation of FADD functions will improve understanding of tumor growth and the immune escape mechanisms, and could open a new field for therapeutic interventions.
Engineered G protein coupled receptors reveal independent regulation of internalization, desensitization and acute signaling
Authors: Scearce-Levie Kimberly , Lieberman Michael D , Elliott Heather H , Conklin Bruce R
Published: February 2005

Background

The physiological regulation of G protein-coupled receptors, through desensitization and internalization, modulates the length of the receptor signal and may influence the development of tolerance and dependence in response to chronic drug treatment. To explore the importance of receptor regulation, we engineered a series of Gi-coupled receptors that differ in signal length, degree of agonist-induced internalization, and ability to induce adenylyl cyclase superactivation. All of these receptors, based on the kappa opioid receptor, were modified to be receptors activated solely by synthetic ligands (RASSLs). This modification allows us to compare receptors that have the same ligands and effectors, but differ only in desensitization and internalization.

Results

Removal of phosphorylation sites in the C-terminus of the RASSL resulted in a mutant that was resistant to internalization and less prone to desensitization. Replacement of the C-terminus of the RASSL with the corresponding portion of the mu opioid receptor eliminated the induction of AC superactivation, without disrupting agonist-induced desensitization or internalization. Surprisingly, removal of phosphorylation sites from this chimera resulted in a receptor that is constitutively internalized, even in the absence of agonist. However, the receptor still signals and desensitizes in response to agonist, indicating normal G-protein coupling and partial membrane expression.

Conclusions

These studies reveal that internalization, desensitization and adenylyl cyclase superactivation, all processes that decrease chronic Gi-receptor signals, are independently regulated. Furthermore, specific mutations can radically alter superactivation or internalization without affecting the efficacy of acute Gi signaling. These mutant RASSLs will be useful for further elucidating the temporal dynamics of the signaling of G protein-coupled receptors in vitro and in vivo.
Replicative Homeostasis: A fundamental mechanism mediating selective viral replication and escape mutation
Authors: Sallie Richard
Published: February 2005

Hepatitis C (HCV), hepatitis B (HBV), the human immunodeficiency viruses (HIV), and other viruses that replicate via RNA intermediaries, cause an enormous burden of disease and premature death worldwide. These viruses circulate within infected hosts as vast populations of closely related, but genetically diverse, molecules known as "quasispecies". The mechanism(s) by which this extreme genetic and antigenic diversity is stably maintained are unclear, but are fundamental to understanding viral persistence and pathobiology. The persistence of HCV, an RNA virus, is especially problematic and HCV stability, maintained despite rapid genomic mutation, is highly paradoxical. This paper presents the hypothesis, and evidence, that viruses capable of persistent infection autoregulate replication and the likely mechanism mediating autoregulation – Replicative Homeostasis – is described. Replicative homeostasis causes formation of stable, but highly reactive, equilibria that drive quasispecies expansion and generates escape mutation. Replicative homeostasis explains both viral kinetics and the enigma of RNA quasispecies stability and provides a rational, mechanistic basis for all observed viral behaviours and host responses. More importantly, this paradigm has specific therapeutic implication and defines, precisely, new approaches to antiviral therapy. Replicative homeostasis may also modulate cellular gene expression.
Inhibition of human immunodeficiency virus type-1 (HIV-1) glycoprotein-mediated cell-cell fusion by immunor (IM28)
Authors: Mavoungou Donatien , Poaty-Mavoungou Virginie , Akoume Marie-Yvonne , Ongali Brice , Mavoungou Elie
Published: February 2005

Background

Immunor (IM28), an analog of dehydroepiandrosterone (DHEA), inhibits human immunodeficiency virus type-1 (HIV-1) by inhibiting reverse transcriptase. We assessed the ability of IM28 to inhibit the cell-cell fusion mediated by HIV envelope glycoprotein in an in vitro system. For this purpose, we co-cultured TF228.1.16, a T-cell line expressing stably HIV-1 glycoprotein envelopes, with an equal number of 293/CD4+, another T cell line expressing CD4, and with the SupT1 cell line with or without IM28.

Results

In the absence of IM28, TF228.1.16 fused with 293/CD4+, inducing numerous large syncytia. Syncytia appeared more rapidly when TF228.1.16 was co-cultured with SupT1 cells than when it was co-cultured with the 293/CD4+ cell line. IM28 (1.6 – 45 μg/ml) completely inhibits cell-cell fusion. IM28 also prevented the development of new syncytia in infected cells and protected naive SupT1 cells from HIV-1 infection. Evaluation of 50% inhibitory dose (IC50) of IM28 revealed a decrease in HIV-1 replication with an IC50 of 22 mM and 50% cytotoxicity dose (CC50) as determined on MT2 cells was 75 mM giving a selectivity index of 3.4

Conclusions

These findings suggest that IM28 exerts an inhibitory action on the env proteins that mediate cell-cell fusion between infected and healthy cells. They also suggest that IM28 interferes with biochemical processes to stop the progression of existing syncytia. This property may lead to the development of a new class of therapeutic drug.
Profile of Patients With Kaposi's Sarcoma in the Era of Highly Active Antiretroviral Therapy
Authors: Gallafent James H. , Buskin Susan E. , De Turk Peter B. , Aboulafia David M.
Published: February 2005

Purpose

Since the advent of highly active antiretroviral therapy (HAART), the incidence of Kaposi's sarcoma (KS) among AIDS patients has declined both nationwide and in King County, Washington. We sought to compare clinical parameters of patients diagnosed with KS in the pre-HAART (1990 to 1996) and HAART (1997 to 2002) eras.

Methods

We used patient data abstracted from the Adult/Adolescent Spectrum of HIV-Related Diseases study of Public Health—Seattle and King County.

Results

Patients diagnosed with KS in the HAART era (n = 40) were significantly more likely (P < .05) than pre–HAART-era KS patients (n = 366) to be diagnosed with alcohol problems (43% v 18%), noninjection drug use (45% v 18%), injection drug use (25% v 10%), psychosis (25% v 13%), and hypertension (13% v 2%). Although median CD4+ count and HIV-1 viral load at the time of KS diagnosis were not significantly different between the two groups, significantly fewer (P < .01) HAART-era KS patients developed opportunistic illnesses (OIs) during their follow-up. The risk of dying among KS patients diagnosed in the HAART era is significantly lower (P < .01) than for KS patients diagnosed in the pre-HAART era (hazard ratio, 0.24).

Conclusion

Although HAART-era KS patients in King County were as likely to have a depleted CD4+ cell count and high HIV-1 viral loads at the time of KS diagnosis as pre-HAART KS patients, they survived longer and fewer of them were diagnosed with other OIs. They also had an increased prevalence of substance abuse and mental illness, contributing to a dynamic and changing KS clinical profile.
Proopiomelanocortin Processing in the Anterior Pituitary of the Ovine Fetus after Lesion of the Hypothalamic Paraventricular Nucleus
Authors: Bell M. Elizabeth , McDonald Thomas J. , Myers Dean A.
Published: February 2005

The hypothalamic-pituitary-adrenocortical axis plays an essential role in the maturation of fetal organs and, in sheep, birth. Lesioning the paraventricular nucleus (PVN) in fetal sheep prevents adrenocortical maturation and parturition without altering plasma immunoreactive ACTH concentrations. The purpose of this study was to determine the effect of PVN lesion on anterior pituitary processing of proopiomelanocortin (POMC) to ACTH, plasma concentrations of ACTH and ACTH precursors (POMC; 22-kDa proACTH), and expression of subtilisin-like prohormone convertase 3 (SPC3) in corticotropes in fetal sheep. PVN lesion did not affect anterior pituitary POMC and 22-kDa proACTH levels, whereas ACTH was significantly affected. The ACTH precursor (POMC plus 22-kDa proACTH) to ACTH ratio in the anterior pituitary was significantly increased after PVN lesion. Post-PVN lesion, fetal plasma ACTH1–39, was below the limit of detection, whereas ACTH precursors (POMC plus 22-kDa proACTH) were not affected. In the inferior region of the anterior pituitary, 40–50% of corticotropes had detectable SPC3 hybridization signal, and PVN lesion did not change the extent of colocalization of POMC and SPC3, or SPC3 mRNA levels within corticotropes. Neither the percent of corticotropes in the superior region containing SPC3 hybridization (7–12%) or hybridization signal strength was altered in response to PVN lesion. In conclusion, the fetal PVN is necessary for sustaining adequate anterior pituitary processing of POMC to ACTH and ACTH release needed for maturing the adrenal cortex in the sheep fetus.
The use of therapeutic drug monitoring in the management of protease inhibitor-related toxicity
Authors: Forsyth S F , French P D , Macfarlane E , Gibbons S E , Miller R F
Published: February 2005

The aim of this project was to determine whether therapeutic drug monitoring (TDM) and subsequent dose modification is effective in the management of protease inhibitor (PI)-associated toxicity. A retrospective case-notes review of patients who had had TDM for suspected antiretroviral drug toxicity from November 2000 to March 2002 was carried out. This identified six symptomatic patients in whom high plasma drug levels of a PI had been found and subsequent dose modification was associated with improvement/resolution of symptoms. In 5/6 patients viral loads were below the level of detection prior to TDM and remained so after dose reduction of PI. TDM-directed dose modification of PI enables patients to continue effective regimens of highly active antiretroviral therapy, thus avoiding the need to switch the regimen.
Sexually transmitted infections among pregnant women attending antenatal clinics in Mongolia: potential impact on the Mongolian HIV epidemic
Authors: Amindavaa Oyunbileg , Kristensen Sibylle , Pak Chin Y , Khalzan Davaajav , Chultemsuren Byambaa , Randall Andrea S , Mikolon Andrea , Lkhamsuren Erdenechimeg , Tulgaa Khosbayar , Chimeddorj Battogtokh , Natsag Udval
Published: February 2005

We conducted Mongolia's first nation-wide cross-sectional survey of sexually transmitted infections (STIs) among pregnant women attending prenatal care. Among our 2000 participants, 386 (19.3%) were infected with Chlamydia trachomatis, 133 (6.7%) with Trichomonas vaginalis, 121 (6.1%) with Neisseria gonorrhoeae, and 128 (6.4%) were seropositive for Treponemal antibodies. None of our participants were seropositive for HIV infection. Additionally, 605 (30.3%) of the women had at least one STI, 133 (6.7%) had a double infection, and 15 (0.8%) had a triple infection. Our results suggest that STIs are a serious problem in Mongolia. Pregnant women represent a lower-risk general population; these high STI rates suggest that at this nascent stage, the identification, treatment, and prevention of STIs as risk factors for HIV transmission are crucial in the prevention of the emerging Mongolian HIV epidemic.