Funding models in palliative care: Lessons from international experience.

BACKGROUND: Funding models influence provision and development of palliative care services. As palliative care integrates into mainstream health care provision, opportunities to develop funding mechanisms arise. However, little has been reported on what funding models exist or how we can learn from them. AIM: To assess national models and methods for financing and reimbursing palliative care. DESIGN: Initial literature scoping yielded limited evidence on the subject as national policy documents are difficult to identify, access and interpret. We undertook expert consultations to appraise national models of palliative care financing in England, Germany, Hungary, Republic of Ireland, New Zealand, The Netherlands, Norway, Poland, Spain, Sweden, Switzerland, the United States and Wales. These represent different levels of service development and a variety of funding mechanisms. RESULTS: Funding mechanisms reflect country-specific context and local variations in care provision. Patterns emerging include the following: Provider payment is rarely linked to population need and often perpetuates existing inequitable patterns in service provision. Funding is frequently characterised as a mixed system of charitable, public and private payers. The basis on which providers are paid for services rarely reflects individual care input or patient needs. CONCLUSION: Funding mechanisms need to be well understood and used with caution to ensure best practice and minimise perverse incentives. Before we can conduct cross-national comparisons of costs and impact of palliative care, we need to understand the funding and policy context for palliative care in each country of interest.

Discovering the hidden benefits of cognitive interviewing in two languages: The first phase of a validation study of the Integrated Palliative care Outcome Scale.

BACKGROUND: The Integrated Palliative care Outcome Scale is a newly developed advancement of the Palliative care Outcome Scale. It assesses patient-reported symptoms and other concerns. Cognitive interviewing is recommended for questionnaire refinement but not adopted widely in palliative care research. AIM: To explore German- and English-speaking patients' views on the Integrated Palliative care Outcome Scale with a focus on comprehensibility and acceptability, and subsequently refine the questionnaire. METHODS: Bi-national (United Kingdom/Germany) cognitive interview study using 'think aloud' and verbal probing techniques. Interviews were audio-recorded, transcribed verbatim and analysed using thematic analysis and pre-defined categories. Results from both countries were collated and discussed. The Integrated Palliative care Outcome Scale was then refined by consensus. SETTING/PARTICIPANTS: Purposely sampled patients from four palliative care teams in palliative care units, general hospital wards and in the community. RESULTS: A total of 15 German and 10 UK interviews were conducted. Overall, comprehension and acceptability of the Integrated Palliative care Outcome Scale were good. Identified difficulties comprised the following: (1) comprehension problems with specific terms (e.g. 'mouth problems') and length of answer options; (2) judgement difficulties, for example, due to the 3-day recall for questions; and (3) layout problems. Combining the results from both countries (e.g. regarding 'felt good about yourself') and discussing them from both languages' perspectives resulted in wider consideration of the items' meaning, enabling more detailed refinement. CONCLUSION: Cognitive interviewing proved valuable to increase face and content validity of the questionnaire. The concurrent approach in two languages - to our knowledge the first such approach in palliative care - benefited the refinement. Psychometric validation of the refined Integrated Palliative care Outcome Scale is now underway.

Increased breast cancer risk in in vitro fertilisation treated women with a multiple pregnancy: a new hypothesis based on historical in vitro fertilisation treatment data.

BACKGROUND: Breast cancer risk is temporarily increased after a full-term pregnancy and declines thereafter, possibly due to increased levels of gonadal and placental hormones during pregnancy. Inconsistent results, however, have been reported after twin pregnancies with higher hormone levels. Among women treated with in vitro fertilisation (IVF), for whom the number of embryos available for implantation is known, we recently observed that a multiple birth after implantation of all transferred embryos is associated with higher levels of vascular endothelial growth factor (VEGF). As VEGF is involved in breast cancer progression, we studied the effects of embryo implantation and a multiple birth on breast cancer risk in a nationwide Dutch cohort of IVF-treated women. METHODS: We performed a cohort analysis among 12,589 women who had been treated with IVF between 1983 and 1995 and completed a risk factor questionnaire between 1997 and 1999. Data on IVF treatment were obtained from medical records. Breast cancer cases were ascertained through linkage with the population-based Netherlands Cancer Registry. Breast cancer risks associated with singleton and multiple births were estimated with Cox regression. FINDINGS: There were 1688 women (13.4%) with multiples, 6027 (47.9%) with singletons and 4874 (38.7%) nulliparous women. Breast cancer occurred in 317 women of whom 57 had multiples. Breast cancer risk was 1.44 times higher in mothers of multiples than in mothers of singletons (95% confidence interval (CI) 1.06-1.97). Risk was highest in women who gave birth to multiples from all embryos transferred (adjusted hazard ratio (HR) 1.86, 95% CI 1.01-3.43), and lower for those with multiples after incomplete embryo implantation (adjusted HR 1.31, 95% CI 0.76-2.25). INTERPRETATION: A woman's potential to implant all transferred embryos may be associated with breast cancer risk. Further research is needed to confirm our results and to identify the underlying biological mechanisms.

Comparison of bivariate and multivariate joint analyses on the selection loss of beef cattle.

For genetic evaluation of beef cattle, univariate or bivariate analyses are often performed as an alternative to decrease the complexity of matrices and mathematical models compared to multivariate analysis, which considers a larger number of joint traits. The use of bivariate methods to calculate genetic predictors may cause bias in the estimation of breeding values and, as a consequence, reclassification of the rank of top-selected sires, resulting in a loss of genetic gain in future generations. The objective of this study was to compare the bivariate and multivariate joint methods of genetic evaluation, verifying the selection loss, and reclassification of the ranking of the best animals with different selection intensities. Records of 431,224 Nellore breed animals were evaluated for birth weight, weaning weight, post-weaning gain, muscle score, scrotal circumference, and selection index. The pedigree file consisted of 505,848 animals, including 218,727 males and 287,121 females. The predicted breeding values were obtained using the program PEST 2, and the complete pedigree analysis was performed by the PopReport software. The results showed that, for the four different selection intensities considered (TOP 10 and 1, 10, and 30%), selection loss and reclassification of animals in ranking, were detected for all traits evaluated when the two methods of analysis were compared.

Use of weaning management group as a random effect for a more robust estimation of genetic parameters for post-weaning traits in Nellore cattle.

Data from 69,525 animals were used to compare two types of analyses, one of them having the weaning management group (WEMANG) included as an effect in the contemporary group (F_WEMANG) and the other considering the weaning management group as a random effect, not related to the mathematical model (R_WEMANG) for post-weaning traits. The components of (co)variance were estimated for pre-weaning traits (birth weight and weaning weight) and for post-weaning traits [scrotal circumference (SC), weight gain from weaning to 18 months of age (WG) and muscle score (MUSC)] in Nellore cattle, based on a complete animal model. Heritability of SC, WG and MUSC for the F_WEMANG model was equal to 0.46 ± 0.02, 0.38 ± 0.03 and 0.26 ± 0.01, and for the R_WEMANG model it was 0.45 ± 0.02, 0.31 ± 0.03 and 0.25 ± 0.01, respectively. Genetic correlations between all the studied traits varied between 0.07 ± 0.01 and 0.77 ± 0.03 in F_WEMANG and between 0.02 ± 0.01 and 0.76 ± 0.04 in R_WEMANG. The R_ WEMANG model allowed a decrease in the number of contemporary groups as well as an increase in the number of observations per group without significant alterations in heritability coefficients, for the post-weaning traits. Consequently, the analysis became more robust and avoided having contemporary groups with low variability.

How many people need palliative care? A study developing and comparing methods for population-based estimates.

BACKGROUND: Understanding the need for palliative care is essential in planning services. AIM: To refine existing methods of estimating population-based need for palliative care and to compare these methods to better inform their use. DESIGN: (1) Refinement of existing population-based methods, based on the views of an expert panel, and (2) application/comparison of existing and refined approaches in an example dataset. Existing methods vary in approach and in data sources. (a) Higginson used cause of death/symptom prevalence, and using pain prevalence, estimates that 60.28% (95% confidence interval = 60.20%-60.36%) of all deaths need palliative care, (b) Rosenwax used the International Statistical Classification of Diseases and Related Health Problems-10th Revision (ICD-10) causes of death/hospital-use data, and estimates that 37.01% (95% confidence interval = 36.94%-37.07%) to 96.61% (95% confidence interval = 96.58%-96.64%) of deaths need palliative care, and (c) Gómez-Batiste used percentage of deaths plus chronic disease data, and estimates that 75% of deaths need palliative care. SETTING/PARTICIPANTS: All deaths in England, January 2006-December 2008, using linked mortality and hospital episode data. RESULTS: Expert panel review identified changing practice (e.g. extension of palliative care to more non-cancer conditions), changing patterns of hospital/home care and multiple, rather than single, causes of death as important. We therefore refined methods (using updated ICD-10 causes of death, underlying/contributory causes, and hospital use) to estimate a minimum of 63.03% (95% confidence interval = 62.95%-63.11%) of all deaths needing palliative care, with lower and upper mid-range estimates between 69.10% (95% confidence interval = 69.02%-69.17%) and 81.87% (95% confidence interval = 81.81%-81.93%). CONCLUSIONS: Death registration data using both underlying and contributory causes can give reliable estimates of the population-based need for palliative care, without needing symptom or hospital activity data. In high-income countries, 69%-82% of those who die need palliative care.

Preconceptional low-dose aspirin for the prevention of hypertensive pregnancy complications and preterm delivery after IVF: a meta-analysis with individual patient data.

STUDY QUESTION: Does preconceptionally started low-dose aspirin prevent hypertensive pregnancy complications and preterm delivery in IVF patients? SUMMARY ANSWER: The current data do not support the use of preconceptionally started low-dose aspirin treatment for the prevention of hypertensive pregnancy complications and preterm delivery in IVF women. WHAT IS KNOWN ALREADY: Studies starting low-dose aspirin treatment as prevention in the second trimester of pregnancy found no or only moderate reductions in the relative risk of developing pre-eclampsia. Low-dose aspirin was possibly started too late, that is after the first episode of trophoblast invasion. STUDY DESIGN, SIZE, DURATION: We performed a meta-analysis with individual patient data (IPD), in which four authors could provide IPD on a total of 268 pregnancies (n = 131 treated with aspirin, n = 137 placebo). Data on hypertensive pregnancy complications and preterm delivery were collected. PARTICIPANTS/MATERIALS, SETTING, METHODS: All separate databases were merged into a summary database. Treatment effect of aspirin on the incidence of hypertensive pregnancy complications (n = 187) and preterm delivery (n = 180) were estimated with odds ratios (OR) and 95% confidence intervals (95% CI) using multivariable logistic regression. MAIN RESULTS AND THE ROLE OF CHANCE: There were significantly fewer twin pregnancies in the aspirin group (OR 0.55 95% CI 0.30-0.98), but no significant differences for hypertensive pregnancy complications and preterm delivery: for singletons OR 0.62 (95% CI 0.22-1.7) and OR 0.52 (95% CI 0.16-1.7), respectively, as well as for twin pregnancies OR 1.2 (95% CI 0.35-4.4) and OR 1.6 (95% CI 0.51-5.0), respectively. LIMITATIONS, REASONS FOR CAUTION: We have to bear in mind that the included studies showed clinical heterogeneity; there was variation in the duration of low-dose aspirin therapy and degree of hypertension between the different studies. Although we combined IPD from four studies, we have to realize that the studies were not powered for the outcome of the current IPD meta-analysis. WIDER IMPLICATIONS OF THE FINDINGS: Based on the current meta-analysis with IPD we found no confirmation for the hypothesis that preconceptionally started low-dose aspirin reduces the incidence of hypertensive pregnancy complications or preterm delivery in IVF women. Larger studies are warranted.

Factors associated with dizygotic twinning after IVF treatment with double embryo transfer.

BACKGROUND: Dizygotic twin pregnancies after IVF treatment are the result of multiple embryos transferred into the uterine cavity, followed by successful double implantation. Factors that increase the chance of multiple implantation after IVF are relatively unknown. The present study aimed to investigate whether features of body composition, such as maternal height, weight and body mass index (BMI) are associated with an increased chance of dizygotic twinning after IVF with double embryo transfer (DET). METHODS: This study was conducted using data from a large Dutch nationwide cohort that comprised 19 861 women who had IVF or ICSI treatment between 1983 and 1995 (OMEGA study). First 'fresh' IVF and ICSI cycles with DET resulting in a delivery of a singleton or twin (living as well as stillborn) were selected. A multivariable logistic regression analysis was performed, with the delivery of a singleton or twin as the dependent variable and height, weight, BMI, maternal age, number of retrieved oocytes, use of alcohol, smoking, highest level of education and parity as independent variables. RESULTS: Of the 6598 women who completed their first IVF or ICSI cycle, 2375 had DET, resulting in 496 deliveries of 371 singletons and 125 twins. Multivariable regression analysis revealed that tall women (>1.74 cm) and women with a high number of retrieved oocytes (>8) had an increased chance of dizygotic twinning [OR: 1.8 (95% CI: 1.0-3.4) and OR: 2.2 (95% CI: 1.3-3.8), respectively]. CONCLUSIONS: Our data demonstrate that tall stature and increased number of retrieved oocytes independently increase the chance of dizygotic twinning after IVF with DET.

Standardization of catheter load speed during embryo transfer: comparison of manual and pump-regulated embryo transfer.

The position of transfer air bubbles after embryo transfer is related to the pregnancy rate. With the conventional manual embryo-transfer technique it is not possible to predict the final position of the air bubbles. This position mainly depends on the catheter load speed at transfer (injection speed), a parameter that remains uncontrollable with the conventional technique even after standardization of the protocol. Therefore, the development of an automated device that generates a standardized injection speed is desirable. This study aimed to examine the variation in injection speeds in manual embryo transfer and pump-regulated embryo transfer (PRET). Seven laboratory technicians were asked to perform simulated transfers using the conventional embryo-transfer technique. Their injection speeds were compared with that of a PRET device. The results indicate that in manually performed transfers, even after standardization of the protocol, there is still a large variation in injection speed, while a PRET device generates a reliable and reproducible injection speed and therefore brings new possibilities for further standardization of the embryo-transfer procedure. Future research should reveal whether these experiments mimic real clinical circumstances and if a standardized injection speed results in more exact positioning of the transferred embryos and therefore higher pregnancy rates.

Diversity and origin of South African chickens.

The objectives of this study were to analyze the genetic diversity and structure of South African conserved and field chicken populations and to investigate the maternal lineages of these chicken populations. Four South African conserved chicken populations (n = 89), namely, Venda (VD_C), Ovambo, Naked Neck, and Potchefstroom Koekoek from the Animal Production Institute of the Agricultural Research Council, and 2 field populations, the Venda and Ovambo (OV_F), from which the Ovambo and the Venda conservation flocks were assumed to have been sampled, were genotyped for 460 bp of the mitochondrial DNA (mtDNA) D-loop sequence. Haplotypes of these chickens were aligned to 7 Japanese and 9 Chinese and Eurasian chicken mtDNA D-loop sequences taken from GenBank and reflecting populations from presumed centers of domestication. Sequence analysis revealed 48 polymorphic sites that defined 13 haplotypes in the South African chicken populations. All 6 South African conserved and field chicken populations observed were found to be polymorphic, with the number of haplotypes ranging from 3 for VD_C to 8 for OV_F. The lowest haplotype diversity, 0.54 ± 0.08, was observed in VD_C chickens, whereas the highest value, 0.88 ± 0.05, was observed in OV_F chickens. Genetic diversity between the 4 South African conserved and 2 field chicken populations constituted 12.34% of the total genetic variation, whereas within-population diversity constituted 87.66% of the total variation. The median network analysis of the mtDNA D-loop haplotypes observed in the South African conserved and field populations and the reference set resulted in 5 main clades. All 6 South African chickens were equally represented in the major clade, E, which is presumed to be of Indian subcontinent maternal origin and may have its roots in Southeast Asia. The results showed multiple maternal lineages of South African chickens. Conservation flocks and field chicken populations shared the major haplotypes A, D and E, which were presumed to be of Chinese, Southeast Asian, and Indian subcontinental origin.

Genetic diversity and conservation of South African indigenous chicken populations.

In this study, we compare the level and distribution of genetic variation between South African conserved and village chicken populations using microsatellite markers. In addition, diversity in South African chickens was compared to that of a reference data set consisting of other African and purebred commercial lines. Three chicken populations Venda, Ovambo and Eastern Cape and four conserved flocks of the Venda, Ovambo, Naked Neck and Potchefstroom Koekoek from the Poultry Breeding Resource Unit of the Agricultural Research Council were genotyped at 29 autosomal microsatellite loci. All markers were polymorphic. Village chicken populations were more diverse than conservation flocks. structure software was used to cluster individuals to a predefined number of 2 ≤ K ≤ 6 clusters. The most probable clustering was found at K = 5 (95% identical runs). At this level of differentiation, the four conservation flocks separated as four independent clusters, while the three village chicken populations together formed another cluster. Thus, cluster analysis indicated a clear subdivision of each of the conservation flocks that were different from the three village chicken populations. The contribution of each South African chicken populations to the total diversity of the chickens studied was determined by calculating the optimal core set contributions based on Marker estimated kinship. Safe set analysis was carried out using bootstrapped kinship values calculated to relate the added genetic diversity of seven South African chicken populations to a set of reference populations consisting of other African and purebred commercial broiler and layer chickens. In both core set and the safe set analyses, village chicken populations scored slightly higher to the reference set compared to conservation flocks. Overall, the present study demonstrated that the conservation flocks of South African chickens displayed considerable genetic variability that is different from that of the assumed founder populations (village chickens).

Is aspirin effective in women undergoing in vitro fertilization (IVF)? Results from an individual patient data meta-analysis (IPD MA).

BACKGROUND: Aspirin is believed to improve the outcome of IVF, but previous conventional meta-analyses on the subject are conflicting. Therefore, we performed a meta-analysis with individual patient data (IPD MA) of randomized clinical trials (RCTs) on the subject. METHODS: A systematic literature search was conducted to identify RCTs assessing the effectiveness of aspirin in IVF. Authors were asked to share their original data. In a one step meta-analytic approach, the treatment effect of aspirin was estimated with odds ratios (ORs) and 95% confidence intervals (CIs) using logistic regression, based on the intention to treat principle. RESULTS: Ten studies fulfilled the inclusion criteria. Authors of six studies provided IPD, including 1119 patients (562 placebo and 557 aspirin). There were 160 clinical pregnancies in the aspirin (28.8%) and 179 (31.9%) in the placebo group [OR 0.86, 95% CI (0.69-1.1)]. There were 129 ongoing pregnancies in the aspirin (23.6%) and 147 in the placebo group (26.7%) [OR 0.85, 95% CI (0.65-1.1)]. Whereas the conventional meta-analysis limited to studies that could provide IPD showed an OR of 0.89 (95% CI 0.69-1.2), the conventional meta-analysis limited to the eight studies of which method of randomization could be confirmed showed an OR of 0.94 (95% CI 0.76-1.17) and the conventional meta-analysis including all 10 eligible RCTs identified with our search changed the OR to 1.07 (95% CI 0.81-1.41). This difference in direction of effect, derived from the studies not able to share IPD of which quality of randomization could not be confirmed. CONCLUSIONS: Aspirin does not improve pregnancy rates after IVF.

Genetic diversity in farm animals--a review.

Domestication of livestock species and a long history of migrations, selection and adaptation have created an enormous variety of breeds. Conservation of these genetic resources relies on demographic characterization, recording of production environments and effective data management. In addition, molecular genetic studies allow a comparison of genetic diversity within and across breeds and a reconstruction of the history of breeds and ancestral populations. This has been summarized for cattle, yak, water buffalo, sheep, goats, camelids, pigs, horses, and chickens. Further progress is expected to benefit from advances in molecular technology.

POPREP: a generic report for population management.

Genetic variation provides a basis upon which populations can be genetically improved. Management of animal genetic resources in order to minimize loss of genetic diversity both within and across breeds has recently received attention at different levels, e.g., breed, national and international levels. A major need for sustainable improvement and conservation programs is accurate estimates of population parameters, such as rate of inbreeding and effective population size. A software system (POPREP) is presented that automatically generates a typeset report. Key parameters for population management, such as age structure, generation interval, variance in family size, rate of inbreeding, and effective population size form the core part of this report. The report includes a default text that describes definition, computation and meaning of the various parameters. The report is summarized in two pdf files, named Population Structure and Pedigree Analysis Reports. In addition, results (e.g., individual inbreeding coefficients, rate of inbreeding and effective population size) are stored in comma-separate-values files that are available for further processing. Pedigree data from eight livestock breeds from different species and countries were used to describe the potential of POPREP and to highlight areas for further research.

Mitochondrial DNA D-loop sequences suggest a Southeast Asian and Indian origin of Zimbabwean village chickens.

This study sought to assess mitochondrial DNA (mtDNA) diversity and phylogeographic structure of chickens from five agro-ecological zones of Zimbabwe. Furthermore, chickens from Zimbabwe were compared with populations from other geographical regions (Malawi, Sudan and Germany) and other management systems (broiler and layer purebred lines). Finally, haplotypes of these animals were aligned to chicken sequences, taken from GenBank, that reflected populations of presumed centres of domestication. A 455-bp fragment of the mtDNA D-loop region was sequenced in 283 chickens of 14 populations. Thirty-two variable sites that defined 34 haplotypes were observed. In Zimbabwean chickens, diversity within ecotypes accounted for 96.8% of the variation, indicating little differentiation between ecotypes. The 34 haplotypes clustered into three clades that corresponded to (i) Zimbabwean and Malawian chickens, (ii) broiler and layer purebred lines and Northwest European chickens, and (iii) a mixture of chickens from Zimbabwe, Sudan, Northwest Europe and the purebred lines. Diversity among clades explained more than 80% of the total variation. Results indicated the existence of two distinct maternal lineages evenly distributed among the five Zimbabwean chicken ecotypes. For one of these lineages, chickens from Zimbabwe and Malawi shared major haplotypes with chicken populations that have a Southeast Asian background. The second maternal lineage, probably from the Indian subcontinent, was common to the five Zimbabwean chicken ecotypes, Sudanese and Northwest European chickens as well as purebred broiler and layer chicken lines. A third maternal lineage excluded Zimbabwean and other African chickens and clustered with haplotypes presumably originating from South China.

A protocol for the cryoconservation of breeds by low-cost emergency cell banks - a pilot study.

A protocol was developed for collection and storage of somatic cell samples under adverse conditions with little infrastructure, for somatic-cell banks as a backup for endangered livestock breeds. The procedure, which is uniform across species, includes sample collection with ear taggers with an integrated tag/vial system, and recording of global positioning system (GPS) coordinates, digital images and breed information. In a pilot study, the procedures were tested on six local Vietnamese populations of pigs, sheep and goats. Initial investment was around €3000, while the total variable cost for sampling one breed with 25 females and 25 males was less than €1000. With support from local organisations, the sampling of six breeds with 300 animals was carried out in 2 months. The protocol and the complete workflow for setting up a somatic-cell bank, together with data collection, are described. The procedure has proved practicable and exceedingly cheap relative to the cryopreservation of semen or embryos.

Absence of population substructuring in Zimbabwe chicken ecotypes inferred using microsatellite analysis.

The objective of this study was to investigate the population structure of village chickens found in the five agro-ecological zones of Zimbabwe. Twenty-nine microsatellites were genotyped for chickens randomly selected from 13 populations, including the five eco-zones of Zimbabwe (n = 238), Malawi (n = 60), Sudan (n = 48) and six purebred lines (n = 180). A total of 280 alleles were observed in the 13 populations. Forty-eight of these alleles were unique to the Zimbabwe chicken ecotypes. The average number (+/-SD) of alleles/locus was 9.7 +/- 5.10. The overall heterozygote deficiency in the Zimbabwe chickens (F(IT) +/- SE) was 0.08 +/- 0.01, over 90% of which was due to within-ecotype deficit (F(IS)). Small Nei's standard genetic distances ranging from 0.02 to 0.05 were observed between Zimbabwe ecotypes compared with an average of 0.6 between purebred lines. The structure software program was used to cluster individuals to 2

Thiopurine metabolism and identification of the thiopurine metabolites transported by MRP4 and MRP5 overexpressed in human embryonic kidney cells.

Mercaptopurines have been used as anticancer agents for more than 40 years, and most acute lymphoblastic leukemias are treated with 6-mercaptopurine (6MP) or 6-thioguanine (TG). Overexpression of the two related multidrug resistance proteins MRP4 and MRP5 has been shown to confer some resistance against mercaptopurines, which has been attributed to extrusion of mercaptopurine metabolites by these transporters. We have analyzed the mercaptopurine metabolites formed in human embryonic kidney cells and determined which metabolites are extruded by MRP4 and MRP5. Incubation with 6MP led to the formation of thioinosine and thioxanthosine metabolites and we found that thio-IMP was transported by both MRP4 and MRP5; MRP5 showed the highest transport rate. In contrast, only MRP5 transported thioxanthosine monophosphate (tXMP). During incubation with TG, the monophosphorylated form of thioguanosine was transported by both MRP4 and MRP5; the highest transport rate was for MRP4. Similarly, only 6-methyl-thio-IMP was formed during incubation with 6-methyl mercaptopurine riboside. This compound was a substrate for both MRP4 and MRP5; MRP4 showed the highest transport rate. Our results show that all major thiopurine monophosphates important in the efficacy of mercaptopurine treatment are transported by MRP4 and MRP5, although the substrate specificity of the two transporters differs in detail.

Characterization of the binding of urokinase-type plasminogen activator to the asialoglycoprotein receptor.

In order to study the role of the asialoglycoprotein receptor (ASGPr) in the rapid plasma clearance of urokinase-type plasminogen activator (u-PA), a microtiter plate binding assay was developed using ASGPr purified from rat liver extracts. Urinary two-chain u-PA bound to immobilized ASGPr in a saturable manner with an EC50 of 0.2 microM. Binding was inhibited by rabbit antibodies against the ASGPr. In line with the known carbohydrate specificity of the ASGPr, GalNAc proved to be the most effective inhibitor from a series of monosaccharides, followed by Gal and Fuc, whereas GlcNAc was ineffective. The N-linked oligosaccharides of urinary u-PA do not terminate with the common Gal-GlcNAc element, but with a GalNAc-GlcNAc element which is partially sulfated. Sulfated forms of u-PA were separated from non-sulfated forms by using the lectin Wisteria floribunda agglutinin. Only the non-sulfated forms of u-PA (30% of the total) appeared to bind to the ASGPr. From different u-PA preparations used for thrombolytic therapy only urinary u-PA and u-PA produced by kidney cell cultures strongly bound to the ASGPr, whereas (recombinant) u-PA expressed in mouse myeloma cells, Chinese hamster ovary cells or E. coli scarcely bound to the receptor. It is concluded that u-PA bearing non-sulfated GalNAc-GlcNAc elements is specifically recognized by the ASGPr present on liver cells.

Consumption of fructooligosaccharides and nitrogen excretion in cats.

In a cross-over study with adult cats the effect on nitrogen (N) excretion of a diet supplemented with fructooligosaccharides (FOS) was compared with a diet supplemented with an equal amount of fructose and glucose. FOS raised N excretion with faeces by 26% (P < 0.05) and non-significantly lowered N excretion with urine by 5%. Thus, there was a shift in N excretion from urine to faeces. The amount of faecal dry matter was significantly higher (by 23.3%) when FOS was consumed.