The nitrogen fertilizer replacement values of incorporated legumes residue to wheat on vertisols of the Ethiopian highlands

Soil fertility depletion and continuous cereal cropping are reducing crop production in Ethiopia. Integrated Soil Fertility Management (ISFM) is a good approach for resource-poor farmers because ISFM can help reduce the need for inorganic fertilizer by increasing nitrogen (N) availability in the soil. The study aimed to investigate the effect of preceding crops, legume residue management practices, and N levels on wheat planted. The experiment was set up using a split plot in a randomized complete block design with three replications. The N fertilizer replacement value method was used to estimate the N contribution of legumes to a succeeding wheat crop. The results showed that grain yield and N uptake of wheat crops varied in response to N fertilizer, legume residue management treatments, and tillage practices. Legume residue incorporation positively influenced the agronomic parameters of wheat compared to teff and fallow wheat rotations. The average N fertilizer replacement value from legume rotation was 18-46 kg ha-1. This study showed that a one-year legume-in-biannual wheat rotation is preferable to lying bare fallow during the cropping season. Nevertheless, drainage during legume and wheat cropping is a condition for providing full positive impacts.

Effects of land-use-cover-changes on selected soil physicochemical properties along slope position, Coka watershed, Southern Ethiopia

Land-use changes along slope position can have a major positive or negative impact on soil environment and agricultural productivity. Relevant information to understand the negative effect of land-use change and slope variability on soil property is a vital element to monitor, plan and make the decision to improve productivity and restore the environment. The aim was to examine the effects of land-use-cover-changes along slope position on the selected soil physicochemical properties in the Coka watershed. Soil samples were gathered from 5 nearby land uses, namely forestland, grassland, bushland, cultivated land, and bare-land, and 3 slope positions (upper, middle, and lower slope) at 0-30 cm soil-depth, analyzed in Hawassa University Soil testing laboratory. The results show that the highest field capacity, available water-holding, porosity, silt, nitrogen, pH-value, cation exchange capacity, sodium, magnesium, and calcium were in forestlands and lower-slope. The highest water-permanent-wilting-point, organic-carbon, soil-organic-matter, and potassium were in bushland; bulk density was in bare land while the highest clay and available-phosphorus were revealed in cultivated land and lower slope. Most soil properties showed a positive correlation with each other except bulk density which has a negative correlation with all soil properties. Generally, cultivated land and bare land have the least concentration in most soil properties which indicates of increasing degradation rate in the area. Thus, soil-organic-matter and other yield-limiting nutrients should be improved in cultivated land to maximize productivity by using an integrated implementation of soil fertility management through cover crops and rotation, compost, manures, and minimum tillage; and amending soil pH-value by liming.

Effect of lime rates and method of application on soil properties of acidic Luvisols and wheat (Triticum aestivum, L.) yields in northwest Ethiopia

Soil acidity has become a major constraint that threatens sustainable agricultural production in Ethiopia. This study was conducted to evaluate effects of lime rates and application methods on selected soil properties and wheat (Triticum aestivum, L.) yields on acidic Luvisols of northwestern Ethiopia. The treatments included control, 0.5, 1, 2 and 3 t ha^-1 lime drilled along the seed rows and 2, 3, 6 and 12 t ha^-1 lime applied in broadcasting method. The experiment was arranged in a randomized complete block design (RCBD) with three replications. Lime rates applied for this experiment were quantified using exchangeable acidity and Buffer pH methods. To analyze selected soil properties, composite soil samples were collected immediately before sowing and after harvest. Results revealed that liming significantly increased soil pH, available phosphorus, and exchangeable bases but markedly reduced exchangeable Al³⁺ contents. The lime rates determined by buffer pH method were greater in ameliorating soil acidity, increasing soil nutrients status and crop yields than exchangeable acidity. Besides, lime application along the row was better in overcoming soil acidity constraints and increasing crop yields compared to broadcast application. Application of 12 t ha^-1 lime in the broadcasting method, 3 t ha^-1 and 2 t ha^-1 lime drilling along the row increased wheat grain yield by 65.10, 49.80 and 27.05%, respectively, compared to the control. Likewise, partial budget analysis showed that the highest net benefit (51,537 Birr ha^-1) was obtained from plots amended with 3 t ha^-1 lime while the lowest economic profit (31,627.5 Birr ha^-1) was recorded from treatments that received 12 t ha^-1 lime. Thus, we concluded that application of 3 t ha^-1 lime in row is a promising practice to mitigate soil acidity and increase available nutrients, exchangeable bases and crop yields in the study area and similar soil types elsewhere.

Dry matter production, nitrogen yield and estimation of nitrogen fixation of legumes on vertisols of the Ethiopian highlands

Traditional land management techniques on vertisols frequently lead to soil fertility loss and land degradation. The objective of this study was to evaluate the impact of improved land preparation methods on the dry biomass and nitrogen (N) content of two legume species grown under two phosphorus fertilizer applications. The experimental design employed for these experiments was a randomized complete block design, with six treatments and four replications. Land preparation methods and phosphorus application significantly (P < 0.05) increased biomass production and N content in legumes. Over years and land preparation methods, vetch N accumulation was superior (P < 0.05) to clover and teff (Eragrostis teff). Such a large amount of N accumulation may have a positive contribution to subsequent crops when incorporated into the soil. Land preparation methods and years influenced soil mineral N accumulation, particularly under legumes. The N balance values indicated that it differed among species, land preparation methods, and P treatments over the year. The N balance of vetch +P ranged from 67.1 to 185.9 kg N ha^-1 over years and land preparation methods, whereas the comparable figure for vetch-P was 40.3-141.9 kg N ha^-1. Similarly, the N balance in clover-P ranged from 13.0 to 67.2 kg N ha^-1, and in clover +P from 13.8 to 98.6 kg N ha^-1. Teff's N balance has never exceeded 35 kg ha^-1 over the years.

Effects of habitat gradient and agro-climatic variation on selected soil physical and chemical properties in the Bale Mountains national park, south-eastern Ethiopia

Background

Increasing evidence suggests that anthropogenic effects are responsible for drastic changes in landscape patterns and ecosystem services. This study aims to assess the effects of landscape change and agro-climatic variation on selected soil physical and chemical properties in the Bale Mountains national park. A combination of stratified and systematic sampling techniques was employed to draw representative soil samples. A total of 72 soil samples (3 agro-climatic zones × 3 land cover types × 2 habitat gradients × 4 replications = 72) at a depth of 0–20 cm were collected for the soil physical and chemical property analysis. A two-way analysis of variance was conducted to determine the level of variation in soil parameters. Tukey’s honest significance difference (HSD) test was used to compare treatment means at a 0.05 level of significance.

Results

The results suggest that soil parameters differed significantly (p < 0.05) among agro-climatic zones, land cover, and habitat gradients. The soil pH, SOC, TN, AP, CEC and clay content were significantly higher in the lower altitude, natural vegetation and interior habitat, whereas the soil sand and silt content as well as the soil bulk density were significantly higher in the farmland and edge habitat.

Conclusions

Conservation and restoration priority should be given to those vegetation types and ecosystems that are highly affected by human interferences such as the grassland in the middle altitude, ericaceous land in the higher altitude, and moist forest in the lower altitudes.

Soil type and fertilizer rate affect wheat (Triticum aestivum L.) yield, quality and nutrient use efficiency in Ayiba, northern Ethiopia

The blanket NP fertilizer recommendation over the past five decades in Ethiopia did not result in a significant increment of crop productivity. The main lack of success was highly linked to the extrapolating approach of one site success to others without considering the climate, soil, and ecological setting and variations. As a result, a new fertilization approach was desperately needed, and with this premise, new blended fertilizers are now being introduced to replace the conventional approach. Thus, the objective of this study was to examine the effect of NPSZnB blended fertilizer on bread wheat yield attributes, quality traits and use efficiency in two different soil types under rain-fed conditions in Ayiba, northern Ethiopia. Relevant agronomic data were evaluated and recorded from plots of each soil types for analysis. The analysis of variance revealed a significant (p < 0.001) variation on all the agronomic and grain quality traits due to the main and interaction effects of soil type and fertilizer treatment factors. Most agronomic and quality characteristics recorded the highest result in the highest treatment applications (175 and 150 kg NPSZnB ha^-1) in both soils. Yield and grain quality traits of bread wheat was also found better under fertilized plots than unfertilized plots. In both soil types increasing application of the new blended fertilizer rate from 50-175 kg NPSZnB ha^-1 showed an increasing trend in grain yield from 1.6 to 4.3 and 2.5 to 5.4 t ha^-1 in Vertisol and Cambisol soils, respectively. The varied yield as a response of fertilizer treatments across soils signifies soil-specific fertilization approach is critically important for production increment. On the other hand, based on the partial budget analysis the highest net benefit with the highest marginal rate of return in both Vertisol and Cambisol soils were obtained when treated with 100 and 125 kg NPSZnB ha^-1, respectively. Therefore, to produce optimum bread wheat yield under rainfed conditions in Ayiba (northern Ethiopia) fertilizing Vertisols with 100 kg NPSZnB ha^-1 and fertilizing Cambisols with 125 kg NPSZnB ha^-1 is recommended.

Expressing carbon storage in economic terms: The case of the upper Omo Gibe Basin in Ethiopia

Terrestrial carbon storage is important for planning decisions regarding climate change. Therefore, modelling the spatial distribution of carbon storage and valuation can help restore the sustainability of the ecosystems. This study aimed at showing the spatial and temporal variations in carbon storage and valuation in the upper Omo Gibe Basin. Land use/cover and carbon pool data based on field data collection and laboratory analyses supported by GIS and remote sensing were used. The Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) software was used for modelling carbon storage. The Global voluntary carbon market price and Tropical Economics of Ecosystems and Biodiversity (TEEB) data were used for describing carbon storage in economic terms. ANOVA was carried out to detect significant differences in carbon stock correlation with parameters. The results show that the annual carbon stock declined by 0.37 t/ha and the carbon market declined from USD 25.04 billion in 1988 to USD 24.01 billion in 2018. The highest loss of carbon storage and valuation was found in forest land followed by grazing land. Moreover, carbon stock was positively correlated with NDVI and habitat quality (p < 0.05). Slopes did not affect carbon stock (p > 0.05). This study helps promote and enhance carbon trading.

Evaluation of Water Provision Ecosystem Services Associated with Land Use/Cover and Climate Variability in the Winike Watershed, Omo Gibe Basin of Ethiopia

The provision of freshwater is essential for sustaining human life. Understanding the water provision modelling associated with the Land Use/Cover (LUC) change and climatic factors is vital for landscape water resource management. The Winike watershed is the largest tributary in the upper Omo Gibe basin of Ethiopia. This research aims to analyze the spatial and temporal change in the water yield to investigate the water yield contribution from the watershed based on the variation in input parameters. The Integrated Valuation of Ecosystem Services and Tradeoffs Tool (InVEST) water yield model was used to evaluate the spatial and temporal variation of the water yield in different years (1988, 1998, 2008 and 2018). The data required for this model include LUC data from satellite images, reference evapotranspiration, root depth, plant available water, precipitation, season factor (Z), and a biophysical table. The analysis of LUC change shows a rapid conversion of grazing land, shrubland, and forest land into cultivated land. There has been a significant variation in water provision, which increased from 1.83 × 10⁹ m³ in 1988 to 3.35 × 10⁹ m³ in 2018. Sub-watersheds 31, 32, and 39 in the eastern part of the watershed contributed more water due to higher precipitation and lower reference evapotranspiration. The major increase in the contribution of water yield was in built-up land by 207.4%, followed by bare land, 148.54%, and forest land by 63%. Precipitation had a greater impact on water yield estimation compared with the other input parameters. Hence, this research helps decision-makers to make informed decisions regarding new policies for LUC change improvement to maintain the water resources in the Winike watershed.

Characterization and classification of soils of Bako Tibe District, West Shewa, Ethiopia

The study was carried out at Bako Tibe District, West Shewa zone, Oromiya Region of Ethiopia, to characterize and classify agriculturally important acidic soils. Four soil types were considered and six representative pedons were opened and a total of 27 disturbed and 20 core ring soil samples were collected from identified horizons of each pedon and analyzed. The field and laboratory data revealed the soils were clay and sandy clay in texture, slightly acidic to strongly acidic in reaction (pH 5.2–6.63). The organic carbon content of the soil ranges between moderate 21.4 g kg⁻¹ to high 30 g kg⁻¹ for surface soil while very low (4 g kg⁻¹) to high (26 g kg⁻¹) for sub-surface soils. Both the surface and subsurface soils were very low (1.7–2.2 g kg⁻¹) in total N and deficient (5.99–7.85 mg kg⁻¹) in available P content. The cation exchange capacity (CEC) was high for all surface and sub-surface percent base saturation was low (25 cmol ₍₊₎kg⁻¹) for Alisols and medium for Nitisols, Luvisols, and Cambisols (51 and 50 cmol₍₊₎kg⁻¹). The soils were sufficient in available Fe, Mn, and Zn but deficient in B and Cu. Pedon-1 was Dystric, Rhodic Nitisols (Humic); pedon-2, Dystric Nitisols (Humic); pedon-3, Umbric Nitisols; pedon-4, Rhodic Alisols (Hyperdystric); pedon-5, Rhodic Luvisols (Hypereutric); pedon-6, Leptic Cambisols (Humic). Soil characterization is helpful to use the land according to its capability and limitations. pedons 2 and 4 were categorized under LCC IIs. pedons 1, 3, and 5 were grouped within LCC IIIes while Pedon 6 was grouped under LCC IVes. All the soil profiles studied can be used for crop production with appropriate management practices. Different agronomic and physical soil and water conservation measures such as cover crops, counter farming, graded bands, and lime application are some of the corrective measures for the limitations.

Allometric equations for selected Acacia species (Vachellia and Senegalia genera) of Ethiopia

BACKGROUND

Allometric equations are used to estimate biomass and carbon stock of forests. In Ethiopia, despite the presence of large floral diversity, only a few site-specific allometric equations have been developed so far. This study was conducted in the Omo-Gibe woodland of south-western Ethiopia to develop an allometric equation to estimate the Above-ground Biomass (AGB) of the four Acacia species (Senegalia polyacantha, Vachellia seyal, Vachellia etbaica and Vachellia tortilis). Fifty-four (54) Acacia trees were sampled and measured within 35 temporarily established square plots. In each plot, dendrometric variables were measured to derive the models based on combinations of Diameter at Breast Height (DBH), height, and wood density as predictor variables. Model performance was evaluated using goodness-of-fit statistics. The biomass was compared using four allometric biomass models that have been widely used in the tropics.

RESULTS

The model containing DBH alone was more accurate to estimate AGB compared to the use of multiple predictor variables. This study, therefore, substantiated the importance of site-specific allometric equations in estimating the AGB of Acacia woodlands. This is because a site-specific allometric equation recognizes the environmental factors, vegetation types and management practices.

CONCLUSIONS

The results of this study contribute to a better understanding of allometric equations and an accurate estimate of AGB of Acacia woodlands in Ethiopia and similar ecosystems elsewhere.

Class and landscape level habitat fragmentation analysis in the Bale mountains national park, southeastern Ethiopia

The changes of natural habitat structure and function due to human interference is hastening worldwide, and it is compulsory to preserve biological resources in a protected system. This study aims to measure the landscape ecological structure and the extent of habitat fragmentation in the Bale mountains national park. The land use/land cover change was determined by interpreting the 1985, 1995, 2005 and 2017 Landsat images with ArcGIS 10.3, and the selected landscape structural metrics was analyzed using FRAGSTATS 4.2.1. All land cover classes showed a declining trend, except the farmland, and grassland depicted the highest area reduction. From 1985 to 2017 grassland, Erica, forestland, and afro-alpine were decreased by 9.36 %, 0.26 %, 0.06 %, and 0.01 %, respectively. Whereas, farmland was increased by 43.67 %. The study area was characterized as progressively fragmented since it was signified by the escalated value of patch number (40.22 %), area-weighted mean shape index (18.84 %), and edge density (22.27 %) and a declined value of mean patch size (28.68 %) and core area (10.60 %) over the study period. Considering this result, there was a high loss in area available for core dependent species, particularly for Mountain nyala in the grasslands and woodlands, Ethiopian wolf in afro-alpine regions, and Bale monkey in the bamboo forest. Both forestland and grassland need a conservation priority since these habitats were the most fragmented and habitat lost area.

An Update on the Management of Budd-Chiari Syndrome

Budd-Chiari syndrome (BCS) is an uncommon condition, caused by obstruction to hepatic venous outflow. It is largely underdiagnosed, and a high index of suspicion is required for any patient with unexplained portal hypertension. The understanding of its etiology and pathology is improving with advances in diagnostic techniques. Recent studies reported an identifiable etiology in > 80% of cases. Myeloproliferative neoplasm (MPN) is the most common etiology, and genetic studies help in diagnosing latent MPN. Better cross-sectional imaging helps delineate the site of obstruction accurately. The majority of BCS patients are now treated by endovascular intervention and anticoagulation which have improved survival in this disease. Angioplasty of hepatic veins/inferior vena cava remains under-utilized at present. While surgical porto-systemic shunts are no longer done for BCS, liver transplantation is reserved for select indications. Some of the unresolved issues in the current management of BCS are also discussed in this review.

Impact of land use type and altitudinal gradient on topsoil organic carbon and nitrogen stocks in the semi-arid watershed of northern Ethiopia

Understanding the role of soils in the soil organic carbon (SOC) and total nitrogen (TN) cycle is essential, assumed that these parameters are among the key soil quality indicators in a given landscape. Nothing but their status is in a state of continual flux due to land-use, soil management practices, and nature of topographic features. Thus, this study has evaluated the effect of land-use types and altitudinal gradient on SOC and TN concentrations and stocks at a watershed scale in northern Ethiopia. A total of 450 topsoil samples (0–30 cm depth) were collected from four different land-use types (Fig.3) across three elevational categories (Fig.1(b)), and their SOC and TN distributions were studied using descriptive statistics and geostatistical methods. Results revealed significant (p < 0.05) differences in SOC and TN concentrations and stocks by land-use type, elevation, and their interactions. The highest SOC stock was recorded at the lower elevation in GL (7.24 Mg C ha⁻¹), followed by PF (4.65 Mg C ha⁻¹) in the middle and GL (4.61 Mg C ha⁻¹) in the upper elevations, respectively. On the other hand, the lowest SOC stock was observed in the BL areas of the upper (2.34 Mg C ha⁻¹) and middle (2.75 Mg C ha⁻¹) elevations. Spatially, the mean SOC stocks of the different land-uses were in the following order: GL > PF > CL > BL in upper elevation, PF > GL > CL > BL in middle elevation, and GL˃CL in lower elevation, respectively. The estimated total SOC and TN stocks of the study watershed were about 46,868.66 ± 7747.38 Mg C and 7,008.02 ± 441.25 Mg N, respectively. The notable difference is attributable to lack of vegetation cover, unsustainable land-use system, and land degradation via water erosion. Hence, these physical landscape disturbances result in disruption of SOC and TN's storage and stability. The SOC and TN stocks have shown a significant (p < 0.05) negative correlation with soil bulk density in the study watershed. The study concludes that variations in the land-use along topographic gradients drive the soils' SOC and TN storage. Therefore, land suitability planning, soil and water conservation measures, and reforestation practices are needed and practical worth increasing SOC and TN storage in the watershed.

Land use/land cover change effect on soil erosion and sediment delivery in the Winike watershed, Omo Gibe Basin, Ethiopia

Information on soil loss and sediment export is essential to identify hotspots of soil erosion to inform conservation interventions in a given watershed. This study investigates the dynamics of soil loss and sediment export associated with land-use/land cover changes and identifying soil loss hotspot areas in the Winike watershed of the Omo-Gibe Basin of Ethiopia. Spatial data collected from satellite images, topographic maps, meteorological and soil data were analyzed. The land-use types in the study area were categorized into six: cultivated land, woodland, forest, grazing, shrubland, and bare land. The Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) of the sediment delivery ratio (SDR) model was used based on the analysis of land use/land cover and RUSLE factors. The results show that total soil loss increased from 774.86 thousand tons in 1988 to 951.21 thousand tons in 2018 while the corresponding sediment export increased by 3.85 thousand tons for the same period. These were subsequently investigated in each land-use type. Cultivated fields generated the highest soil erosion rate, increasing from 10.02 t/ha/year in 1988 to 43.48 t/ha/year in 2018 when compared with the grazing, shrub, forest, wood land and bare land-use types. This corresponds with the expansion of the cultivated area. This is logical as the correlation between soil loss and sediment delivery and expansion of cultivated area is highly significant (p < 0.001). Sub-watershed six (SW-6) showed the highest soil loss (23.17 t/ha/year) while sub-watershed two (SW- 2) has the lowest soil loss (5.54 t/ha/year). This is because SW-2 is situated in the lower reaches of the watershed under dense vegetation cover experiencing less erosion. The findings on the erosion hotspots presented in this study allow prioritizing the segments of the watershed that need immediate application of improved management interventions and informed decision-making processes.

A246 POPULATION WIDE STUDY OF THE EPIDEMIOLOGY AND OUTCOMES OF ANTI-TNF DOSE AUGMENTATION IN INFLAMMATORY BOWEL DISEASE

Background

Inflammatory bowel disease (IBD) patients who experience loss of response to anti-tumor necrosis factor (anti-TNF) therapy are often treated with augmented doses of anti-TNF to recapture response. Despite this, factors associated with dose augmentation and treatment outcomes following dose augmentation remain largely undefined.

Aims

To examine the epidemiology of anti-TNF dose augmentation and determine the associated treatment outcomes among a province-wide cohort of anti-TNF treated IBD subjects.

Methods

The University of Manitoba Inflammatory Bowel Disease Epidemiological Database was used to identify patients receiving infliximab or adalimumab maintenance therapy for IBD in the Canadian province of Manitoba. Anti-TNF dose augmentation was defined as a ≥50% increase in anti-TNF dose or a shortening of dosing interval to ≤42 days for infliximab or ≤10 days for adalimumab. Anti-TNF failure was defined as corticosteroid use, IBD-related hospitalization, resective IBD surgery, or change in anti-TNF agent. Competing risks regression using a proportional subhazards model was used to determine the associations between dose augmentation, anti-TNF failure, anti-TNF discontinuation and a number of patient, disease, and treatment factors.

Results

871 persons (624 Crohn’s disease (CD), 247 ulcerative colitis (UC)) using anti-TNF maintenance therapy were identified. Cumulative incidence of dose augmentation among continued users was 25.7% at 90 days, 52.3% at 1 year, and 72.8% at 5 years. Anti-TNF failure occurred in 261 of 575 dose augmented subjects, with corticosteroid use the most common failure-defining event. Failure of standard dose anti-TNF in the 90 days preceding dose augmentation was strongly associated with failure of dose augmentation (HR 2.98 (2.27–3.93); p&lt;0.0001). Persons with CD were less likely to receive corticosteroids but more likely to switch anti-TNF agents than persons with UC.

Conclusions

Rates of adverse IBD outcomes remain high after dose augmentation, particularly when dose augmentation is undertaken shortly after (or in response to) one of these adverse events. Our data suggest that dose augmentation may not be as effective as uncontrolled observational studies have indicated.

Funding Agencies

None

A107 PATIENT PERSPECTIVES ON THE LONG-TERM MANAGEMENT OF CELIAC DISEASE

Background

Celiac disease (CD) is a common chronic gastrointestinal illness with a range of manifestations. The only available treatment is strict gluten avoidance, therefore patients are effectively self-managed. Despite the critical role patients play in their treatment, patient perspectives on long-term CD care have not been formally assessed and are therefore not represented in current clinical guidelines.

Aims

To determine the opinions of CD patients on the need for long-term CD follow-up, the utility of various aspects of CD follow-up, and the areas in which further information is desired.

Methods

The Manitoba Celiac Disease Cohort includes newly diagnosed adults with elevated TTG and/or EMA antibodies and Marsh III histology. At the 24-month follow-up visit, participants were asked to rate the utility of various aspects of CD care from 1–5 (low-high) and their desire for further information on CD-related issues from 1–6 (low-high).

Results

A total of 213 patients were recruited and 137 participants completed the online survey (median age 41 [interquartile range 29–57] years; 68% female). Adherence to a gluten free diet was variable, with 29% of patients having TTG antibodies above the upper limit of normal.

Two-thirds of participants felt they should be seen regularly for their celiac disease, while 79.8% of those who wished to be followed felt they should be seen every 6–12 months. Blood tests were the most highly rated component of CD care (scored ≥4 by 78% of respondents). Celiac symptom review, information on research in celiac disease, and the opportunity to ask questions about vitamins and supplements were also positively regarded. Diet review was not generally considered helpful. 79% of patients desired further information on research in CD, while approximately 60% desired information on the long-term complications of CD and the risk of nutritional deficiencies.

Conclusions

The majority of CD patients find regular specialist follow-up helpful, particularly for biochemical assessment of disease activity and its complications. Further information on CD research and the long-term complications of CD should be addressed in follow-up visits. These aspects of follow-up care should be reflected in future guidelines.

Funding Agencies

None

Cassava response to the integrated use of manure and NPK fertilizer in Zambia

Cassava is Africa's second most important food source in terms of calories consumed per capita. However, farmers use little or no fertilizer on cassava and scant information is available regarding the cassava yield response to mineral and organic fertilizer inputs in Zambia. This study was undertaken to determine the response of cassava to the integrated use of organic and inorganic nutrient sources in two contrasting agroecological zones of Zambia; Mansa located in Zone III and Kabangwe located in Zone II. The treatments consisted of a factorial combination of four NPK rates (unfertilized control, 50N-11P-41.5K, 100N-22P-83K, and 150N-33P-124.5K kg/ha) with four rates of chicken manure (0, 1.4, 2.8, and 4.2 t/ha). The treatments were laid out in a randomized complete block design with three replications. Cassava height, stem girth, canopy diameter, leaf area index, and chlorophyll index were monitored over time and roots were harvested at 12 months after planting (MAP). Growth parameters and yield varied significantly (p < 0.01) both with NPK, manure application, and their interaction effects at 12 MAP. The combined application of 4.2 t/ha of chicken manure and 100N-22P-83 K kg/ha of mineral fertilizer resulted in the highest yields of 35.2 t/ha at Kabangwe. But, the highest average yield of 34.4 t/ha was recorded with the application of 2.8 t/ha manure and 100N-22P-83 K kg/ha mineral fertilizer at Mansa. This increased treatment yield by 24 and 29% over the sole NPK fertilizer application at Mansa and Kabangwe sites, respectively. Harvest index (HI) was higher when 2.8 t/ha chicken manure was applied in combination with 50N-11P-41.5K kg/ha at Kabangwe. But, the highest HI at Mansa site was achieved with the combination of 2.8 t/ha manure and 100N-22P-83 K kg/ha. This combination also resulted in the highest agronomic efficiency of N, P and K at both sites. It is concluded that cassava productivity and nutrient use efficiency can be improved through the integrated use of NPK and manure in Zambia.

Project Career: Perceived benefits of iPad apps among college students with Traumatic Brain Injury (TBI)

BACKGROUND

Project Career is an interprofessional five-year development project designed to improve academic and employment success of undergraduate students with a traumatic brain injury (TBI) at two- and four-year colleges and universities. Students receive technology in the form of iPad applications ("apps") to support them in and out of the classroom.

OBJECTIVE

To assess participants' perspectives on technology at baseline and perceived benefit of apps after 6 and 12 months of use.

METHODS

This article address a component of a larger study. Participants included 50 college-aged students with traumatic brain injuries. Statistical analysis included data from two Matching Person and Technology (MPT) assessment forms, including the Survey of Technology Use at baseline and the Assistive Technology Use Follow-Up Survey: Apps Currently Using, administered at 6- and 12-months re-evaluation. Analyses included frequencies and descriptives.

RESULTS

Average scores at baseline indicated positive perspectives on technology. At 6 months, quality of life (67%) and academics (76%) improved moderately or more from the use of iPad apps. At 12 months, quality of life (65%) and academics (82%) improved moderately or more from the use of iPad apps.

CONCLUSION

Students with a TBI have positive perspectives on technology use. The results on perceived benefit of apps indicated that students with a TBI (including civilians and veterans) report that the apps help them perform in daily life and academic settings.

Bone mineral density and expression of vitamin D receptor-dependent calcium uptake mechanisms in the proximal small intestine after bariatric surgery

BACKGROUND

Roux-en-Y gastric bypass may lead to impaired calcium uptake. Therefore, operation-specific effects of gastric bypass and vertical banded gastroplasty on bone mineral density (BMD) were examined in a randomized clinical trial. Bone resorption markers and mechanisms of decreased calcium uptake after gastric bypass were investigated using blood and endoscopic samples from two additional patient cohorts.

METHODS

Total BMD and non-weight-bearing skull BMD were measured by dual-energy X-ray absorptiometry at baseline, and 1 and 6 years after gastric bypass or vertical banded gastroplasty in patients who were not receiving calcium supplements. Bone resorption markers in serum and calcium uptake mechanisms in jejunal mucosa biopsies were analysed after gastric bypass by proteomics including radioimmunoassay, gel electrophoresis and mass spectrometry.

RESULTS

One year after surgery, weight loss was similar after gastric bypass and vertical banded gastroplasty. There was a moderate decrease in skull BMD after gastric bypass, but not after vertical banded gastroplasty (P < 0·001). Between 1 and 6 years after gastric bypass, skull BMD and total BMD continued to decrease (P = 0·001). C-terminal telopeptide levels in serum had increased twofold by 18 months after gastric bypass. Proteomic analysis of the jejunal mucosa revealed decreased levels of heat-shock protein 90β, a co-activator of the vitamin D receptor, after gastric bypass. Despite increased vitamin D receptor levels, expression of the vitamin D receptor-regulated calcium transporter protein TRPV6 decreased.

CONCLUSION

BMD decreases independently of weight after gastric bypass. Bone loss might be attributed to impaired calcium absorption caused by decreased activation of vitamin D-dependent calcium absorption mechanisms mediated by heat-shock protein 90β and TRPV6.

Good clinical outcomes following transjugular intrahepatic portosystemic stent-shunts in Budd-Chiari syndrome

BACKGROUND

There have been encouraging reports on transjugular intrahepatic portosystemic stent-shunt (TIPSS) for Budd-Chiari syndrome (BCS). Long-term data are lacking.

AIM

To assess long-term outcomes and validate prognostic scores following TIPSS for BCS.

METHODS

A single centre retrospective study. Patients underwent TIPSS using bare or polytertrafluoroethane (PTFE)-covered stents.

RESULTS

Sixty-seven patients received successful TIPSS between 1996 and 2012 using covered (n = 40) or bare (n = 27) stents. Patients included had a Male: Female ratio of 21:46, and were characterised (mean ± s.d.) by age 39.9 ± 14.3 years, Model of end stage liver disease (MELD) 16.1 ± 7.0 and Child's score 8.8 ± 2.0. Seventy-eight percent had haematological risk factors. Presenting symptoms were ascites (n = 61) and variceal bleeding (n = 6). Nine patients underwent hepatic vein dilatation or stenting prior to TIPSS. Mean follow-up was 82 months (range 0.5-184 months). Fifteen percent had post-TIPSS encephalopathy. Two have been transplanted. Primary patency rates (76% vs. 27%, P < 0.001) and shunt re-interventions (22% vs. 100%, P < 0.001) significantly favoured covered stents. Secondary patency was 99%. Six-, 12-, 24-, 60- and 120-month survival was 97%, 92%, 87%, 80% and 72% respectively. Six patients had liver related deaths. Two patients developed hepatocellular carcinoma. The BCS TIPS PI independently predicted mortality in the whole cohort, but no prognostic score was a significant predictor of mortality after subgroup validation.

CONCLUSIONS

Long-term outcomes following TIPSS for Budd-Chiari syndrome are very good. PTFE-covered stents have significantly better primary patency. The value of prognostic scores is controversial. TIPSS should be considered as first line therapy in symptomatic patients in whom hepatic vein patency cannot be restored.

Central nervous system lipocalin-type prostaglandin D2-synthase is correlated with orexigenic neuropeptides, visceral adiposity and markers of the hypothalamic-pituitary-adrenal axis in obese humans

Lipocalin-type prostaglandin D2-synthase (L-PGDS) is the main producer of prostaglandin D2 (PGD2) in the central nervous system (CNS). Animal data suggest effects of central nervous L-PGDS in the regulation of food intake and obesity. No human data are available. We hypothesised that a role for CNS L-PGDS in metabolic function in humans would be reflected by correlations with known orexigenic neuropeptides. Cerebrospinal fluid (CSF) and serum samples were retrieved from 26 subjects in a weight loss study, comprising a 3-week dietary lead-in followed by 12-weeks of leptin or placebo treatment. At baseline, CSF L-PGDS was positively correlated with neuropeptide Y (NPY) (ρ = 0.695, P < 0.001, n = 26) and galanin (ρ = 0.651, P < 0.001) as well as visceral adipose tissue (ρ = 0.415, P = 0.035). Furthermore, CSF L-PGDS was inversely correlated with CSF leptin (ρ = -0.529, P = 0.005) and tended to correlate inversely with s.c. adipose tissue (ρ = -0.346, P = 0.084). As reported earlier, leptin treatment had no effect on weight loss and did not affect CSF L-PGDS or NPY levels compared to placebo. After weight loss, the change of CSF L-PGDS was significantly correlated with the change of CSF NPY levels (ρ = 0.604, P = 0.004, n = 21). Because of the correlation between baseline CSF L-PGDS levels and visceral adipose tissue, we examined associations with hypothalamic-pituitary-adrenal (HPA) axis components. Baseline CSF L-PGDS was correlated with corticotrophin-releasing hormone (ρ = 0.764, P < 0.001) and β-endorphin (ρ = 0.491, P < 0.001). By contrast, serum L-PGDS was not correlated with any of the measured variables either at baseline or after treatment. In summary, CSF L-PGDS was correlated with orexigenic neuropeptides, visceral fat distribution and central HPA axis mediators. The importance of these findings is unclear but could suggest a role for CSF L-PGDS in the regulation of visceral obesity by interaction with the neuroendocrine circuits regulating appetite and fat distribution. Further interventional studies will be needed to characterise these interactions in more detail.

The lipocalins retinol-binding protein-4, lipocalin-2 and lipocalin-type prostaglandin D2-synthase correlate with markers of inflammatory activity, alcohol intake and blood lipids, but not with insulin sensitivity in metabolically healthy 58-year-old Swedish men

The lipocalins retinol-binding protein (RBP)-4, lipocalin-2 and lipocalin-type prostaglandin D-synthase (L-PGDS) have been suggested to mediate obesity-associated insulin resistance and other metabolic co-morbidities. The role of lipocalins is however controversial and it is unclear whether they have a physiological role in regulation of insulin sensitivity and metabolic function in clinically healthy humans. Therefore, we examined the correlations between serum levels of RBP-4, L-PGDS and lipocalin-2 and insulin sensitivity and other metabolic parameters in non-diabetic subjects selected to display variations in insulin sensitivity. 100 clinically healthy 58-year-old Swedish men were selected by stratified sampling among 818 screened subjects to represent quintiles of varying degrees of insulin sensitivity. Insulin sensitivity was measured by the euglycaemic hyperinsulinaemic clamp method. Serum levels of lipocalins and cytokines were determined using antibody-based techniques. Serum lipids were measured by standardized laboratory methods. None of the measured lipocalins showed any correlations with insulin sensitivity. However, we found that lipocalin-2 and L-PGDS were correlated with each other, but not with RBP-4. Lipocalin-2 and L-PGDS were positively correlated with soluble TNF- receptors 1 and 2 and negatively with alcohol consumption and serum HDL. Further, lipocalin-2 was correlated with interleukin-6 whereas RBP-4 was negatively correlated with TNF-α. □These results suggest that RBP-4, lipocalin-2 and L-PGDS do not regulate insulin sensitivity in healthy men. Rather the expression levels of lipocalin-2 and L-PGDS, but not RBP-4, seemed to reflect inflammatory activity and were inversely correlated with alcohol intake and serum HDL levels.

Familial idiopathic pulmonary fibrosis in association with bone marrow hypoplasia and hepatic nodular regenerative hyperplasia: a new "trimorphic" syndrome

This is the first report of familial idiopathic pulmonary fibrosis associated with hepatic nodular regenerative hyperplasia and bone marrow hypoplasia. Four members of one family presented with this triad of organ dysfunction. The response to immunosuppressive treatment was poor and all four members succumbed to the disease processes. The current literature is reviewed and mechanisms that could have been involved in the development of this new syndrome are proposed.

Sequencing and functional assessment of hPXR (NR1I2) variants in intrahepatic cholestasis of pregnancy

1. The purpose of this study was to evaluate the role of coding variation in hPXR (NR1I2) in intrahepatic cholestasis of pregnancy (ICP) and to functionally asses the response of PXR variants to ligands of interest in ICP. 2. The coding region of hPXR was sequenced in a cohort of 121 Caucasian ICP patients and exon 2 was sequenced in an additional 226 cases. Reporter assays were used to evaluate the function of all known hPXR variants in response to the secondary bile acid lithocholic acid and therapeutic agents rifampicin, ursodeoxycholic acid and dexamethasone. 3. Two coding single nucleotide polymorphisms (C79T and G106A) were detected in the ICP cohort at frequencies consistent with healthy populations. These do not alter hPXR function in response to ligands of interest to ICP. Analysis of all known coding hPXR variants demonstrates that while subtle changes in experimental design mask or may unveil the functional effects of genetic variation, these are not maintained in a standard functional assay. 4. Coding genetic variation in hPXR does not contribute to the aetiology of ICP in Caucasian populations.

Serum lipid and lipoprotein profile of patients with glycogen storage disease types I, III and IX

With current dietary therapy, life expectancy in glycogen storage disease (GSD) has improved considerably and more children reach adulthood. Notwithstanding intensive dietary therapy, moderate to severe hyperlipidaemia is still observed frequently. There is limited information about the type and extent of hyperlipidaemia. We studied the lipid profile in 20 patients, aged 8-54 years, of the three (types I, III and IX) most common forms of adult GSD. Hyperlipidaemia was shown to be type-specific, affecting predominantly patients with GSD type Ia, who showed marked combined hypercholesterolaemia and hypertriglyceridaemia. By contrast, a heterogeneous distribution of HDL was found in patients with GSD I and III. There was no significant difference in Apo Al and Apo B concentrations between groups. In addition, mass measurements of the fractions of VLDL1, VLDL2 and IDL were raised in all patients with GSD Ia by comparison with all other patients with GSD. Patients with GSD type Ia have lipid concentrations and individual mass measurements that are consistent with ranges found in patients who have a significant risk of atherosclerosis. Accumulated evidence, however, suggest GSD type Ia patients do not have an increased risk of atherosclerotic cardiovascular disease (CVD) but the reason remains unknown. Intervention to reduce their lipid levels could therefore be on the basis of seeking to prevent the risk of pancreatitis rather than that of CVD.