bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of applying a bacterial inoculant to silage immediately before feeding on silage intake, digestibility, degradability and rumen volatile fatty acid concentrations in growing beef cattle
Authors: KEADY T. W. J. , STEEN R. W. J.
Published: April 2006

In an experiment, involving twelve male cattle (initially 235 kg live weight), the effects of applying lactic acid bacteria [Lactobacillus plantarum; 109 colony‐forming units (g fresh silage)−1] to grass silage, immediately prior to that silage being fed, on dry‐matter (DM) intake of the silage, degradability of nitrogen (N) and fibre in the rumen, total tract digestibility and composition of rumen fluid in the animals were examined. A grass silage, which had been made from the primary growth of a predominantly perennial ryegrass sward, was offered as the sole diet. The inoculant was applied to the silage at the rate of 2 g of freeze‐dried powder reconstituted in 12 ml of water (kg fresh silage)−1 immediately prior to that silage being fed and an equivalent amount of water was applied to the silage in the control treatment. The two diets were compared in a change‐over design. The silage was well preserved, having a pH and concentrations of ammonia N and butyrate of 3.72, 74 g (kg total N)−1 and 0.11 g (kg DM)−1 respectively. Application of the inoculant significantly increased true protein, acid‐insoluble N and water‐soluble carbohydrate concentrations (P < 0.001) in the diet. Silage DM intake was not significantly increased (P= 0.072) by this of inoculant treatment, which had no significant effect (P > 0.05) on rumen degradability or total tract digestibility of DM, N, neutral detergent fibre or modified acid detergent fibre. Rumen pH, ammonia concentration or the molar proportions of volatile fatty acids were not altered (P>0.05) by inoculant treatment. It is concluded that application of the inoculant to the silage prior to silage being fed did not significantly affect silage DM intake, total tract digestibility, or degradability or fermentation in the rumen of cattle offered grass silage as the sole diet. It is also concluded that the results of this experiment provide no evidence that the mode of action of L plantarum, applied as an additive to grass at ensiling in previous studies, is through ‘direct’ effects in the rumen.
An evaluation of the effects of rate of nitrogen fertilization of grassland on silage fermentation, in‐silo losses, effluent production and aerobic stability
Authors: KEADY T. W. J. , O'KIELY P.
Published: April 2006

A factorial experiment was carried out to evaluate the effects of level of nitrogen (N) application to grassland and subsequent treatment of the herbage at ensiling with formic acid on the rate of silage fermentation, dry‐matter (DM) recovery, aerobic stability and effluent production. Herbage from the primary regrowth of predominantly perennial ryegrass swards received either 72 (LN), 126 (MN) or 180 (HN) kg N ha−1. The herbages were harvested and yield estimated after a 50‐day regrowth interval. After storage for 24 h in polythene bags, the herbages were ensiled, unwilled, in laboratory silos (6 kg capacity) either untreated (UT) or treated with formic acid (F) at 3 ml (kg herbage)−1. Three silos per treatment were opened and sampled on days 1, 3, 6, 15, 50 and 105 after ensiling. The mean herbage yields for the LN, MN and HN swards were 5.2, 6.3 and 6.2 (s.e. = 0.27) t DM ha−1 and there was no carryover effect of nitrogen treatment on the yield of a subsequent 22‐day regrowth harvested on 2 September. As level of fertilizer N application increased, concentrations in the herbage at mowing of crude protein, nitrate and ash increased, DM decreased and water‐soluble carbohydrate and in vitro DM digestibility remained unchanged. Increasing the rate of N fertilizer to the sward resulted in higher silage pH (P< 0.001) and ammonia N concentrations (P <0.001) at each time of sampling. Increasing the rate of fertilizer N increased effluent output (P < 0.001) and DM recovery (P < 0.001). Aerobic stability was improved (P <0.001) by use of high rates of N fertilizer application. Formic acid treatment restricted fermentation and increased effluent output (P <0.001) but had no effect (P > 0.05) on DM recovery. It is concluded that the rate and extent of pH decline was reduced with increasing N application, associated with increased buffering capacity and decreased DM concentrations of the herbage at ensiling. However, increasing the level of N fertilizer applied increased DM recovery and effluent output, and improved aerobic stability of the resulting silages.
Yield and quality of winter and spring triticales for forage and grain
Authors: ROYO C. , PARES D.
Published: April 2006

In field experiments conducted over 2 years in Mediterranean conditions, five winter and five spring triticales were evaluated for forage and grain production in the same cropping season. The experiments had two treatments, namely harvesting for grain only, and dual‐purpose forage and grain production. In the latter treatment, forage was cut when the first node was detectable (Zadoks' stage 31), without removing the apical meristems. Grain was harvested when ripe (Zadoks' stage 92) in both cut and uncut plots.

Environmental conditions affected grain production and protein content more than forage yield and quality. Winter triticales yielded about 43% more forage than spring types, but after forage removal the spring types yielded about 36% more grain than winter triticales.

Reductions in grain yield after clipping were more pronounced in winter (32%) than in spring (19%) types. Forage crude protein content was significantly higher in the spring types studied (24.6%) than in the winter types (23.5%), the opposite being true for fibre content (20.7 and 21.6% respectively). Grain crude protein content did not differ between grain and dual‐purpose treatments, but was higher in the spring triticales (12.8%) than in the winter types (11.9%). There was more variability for the measured traits within the winter triticales studied than within the spring types.
The effect of a high‐magnesium perennial ryegrass variety on the magnesium status of sheep
Authors: BINNIE R. C. , JOHNSTON D. T. , CHESTNUTT D. M. B.
Published: April 2006

An early‐heading variety of perennial ryegrass (Ramore) bred for high magnesium (Mg) content was compared with an early control variety (Frances) for its ability to increase Mg intake, Mg utilization and blood Mg concentration in sheep, and so reduce the incidence of hypomagnesaemic tetany. Swards of the two varieties were established and each was grazed by ewes suckling twin lambs from turn‐out to weaning and thereafter by dry ewes. In early and late season herbage from a proportion of each sward was cut daily and fed fresh to ewes housed indoors in metabolism crates.

Under grazing conditions herbage from Ramore swards had, over the 1992 and 1993 grazing seasons, a higher Mg concentration than Frances (2.35 g kg−1 vs. 2.18 g kg−1; s.e.m. 0.019, P< 0.001). During the spring period there was a higher (P 0.001, s.e.m. 0.0074) Mg concentration in the blood of ewes grazing Ramore (0.854 m mol 1−l) swards compared with those grazing Frances (0.793 m mol 1 −1) whereas during the autumn period blood Mg concentrations were higher in ewes grazing Frances. Ewe and lamb liveweight gains, recorded in 1992 only, were higher on Ramore swards than on Frances swards, although the difference was not significant.

Indoor feeding studies showed that Mg intake was significantly higher (P< 0.001, s.e.m. 0.026) in ewes offered Ramore (1.98 g d−1) herbage compared with those offered Frances (1.74 g d−1) herbage with no significant difference in dry‐matter intake between the two varieties. Apparent availability and retention of Mg were higher for animals fed Ramore during the spring feeding periods than those fed Frances, but during the autumn feeding periods the reverse was true. Under indoor feeding conditions, variety had no significant effect on blood Mg concentrations.

It was concluded that under grazing conditions a high Mg variety could provide an effective means of reducing the incidence of hypomagnesaemic tetany.
Performance of white clover/perennial ryegrass mixtures under cutting
Authors: Elgersma A. , Schlepers H.
Published: April 2006

Clover persistence in mixtures of two varieties of perennial ryegrass (Lolium perenne) with contrasting growth habits and three white clover (Trifolium repens) varieties differing in leaf sizes was evaluated at two cutting frequencies. An experiment was sown in 1991 on a clay soil. The plots received no nitrogen fertilizer. In 1992, 1993 and 1994, mixtures containing the large‐leaved clover cv. Alice yielded significantly more herbage dry matter (DM) and had a higher clover content than mixtures containing cvs Gwenda and Retor. Companion grass variety did not consistently affect yield or botanical composition. Cutting at 2 t DM ha−1 resulted in slightly higher total annual yields than cutting at 1.2 t DM ha−1, but did not affect clover content. In 1992 the mixtures yielded, depending on cutting frequency and variety, 10·6–14·6 t DM ha−1 and 446–599 kg ha−1 N, whereas grass monocultures yielded only 1·2–2·0 t DM ha−1 and 25–46 kg ha−1 N. From 1992 to 1994 the annual mean total herbage yield of DM in the mixtures declined from 12·2 to 10·5 to 8·7 t ha−1, the white clover yield declined from 8·7 to 6·5 to 4·1 t ha−1 and the average clover content during the growing season declined from 71% to 61% to 46%, whereas the grass yield increased from 3·4 to 4·0 to 4·5 t ha−1. The N yield decreased from 507 to 406 to 265 kg N ha−1 and the apparent N fixation from 470 to 380 to 238 kg N ha−1. Nitrate leaching losses during the winters of 1992–93 and 1994–95 were highest under mixtures with cv. Alice, but did not exceed 10 kg N ha−1. The in vitro digestible organic matter (IVDOM) was generally higher in clover than in grass, particularly in the summer months. No differences in IVDOM were found among clover or grass varieties. The experiment will be continued to study clover persistence and the mechanisms that affect the grass/clover balance.
Changes in plant population density, composition and sward structure of a hill pasture during a pastoral fallow
Authors: Nie Z. N. , Mackay A. D. , Barker D. J. , Valentine I. , Hodgson J.
Published: April 2006

Appropriate pre‐sowing methods for the introduction of improved forage legume and grass germplasm are an important issue for hill pasture improvement in New Zealand. A pastoral fallow, which involves not defoliating pasture for a period generally from late spring/early summer to autumn, could create a potentially favourable environment for introducing improved germplasm. A field study was conducted on two aspects (shady and sunny) of moist, low‐fertility hill country with or without added fertilizer (phosphorus and sulphur) in the southern North Island of New Zealand, to investigate the changes in plant population density and sward structure during a full or partial pastoral fallow, compared with a rotationally grazed pasture. A 7‐month (October to May) pastoral fallow dramatically decreased the densities of grass tillers by 72% (P < 0·01), white clover (Trifolium repens L.) growing points by 87% (P < 0·01) and other species by 87% (P < 0·05). The decline in tiller density by pastoral fallow was enhanced on the shady aspect. Fertilizer application increased white clover growing‐point density on the shady aspect (P < 0·05) and grass tiller density on the sunny aspect (P < 0·05). Decreased plant density during pastoral fallowing was attributed to aboveground biomass accumulation, which altered sward structure, leading to interplant competition and mortality by self‐thinning and completion of the life cycle of some matured plants. The plant size‐density relationship during pastoral fallowing in this mixed‐species sward followed the serf‐thinning rule, particularly when the calculation was based on all plant species rather than grass alone. There was no significant (P > 0·05) difference in final plant population density between the 7‐month pastoral fallow and a shorter term (October to December) pastoral fallow. It is concluded that pastoral fallowing effectively reduced the plant population density and altered sward structure of a hill pasture. Such changes create a more favourable environment for the introduction of improved forage species.
Effect of various bale treatments on physical quality and chemical composition of rhodes grass (Chloris gayana) hay
Authors: Haffar I. , Alhadrami G.
Published: April 2006

The effect of harvest season (winter vs. summer), moisture content at baling and bale mass on hay physical quality and chemical composition of two varieties of Rhodes grass (Chloris gayana) was studied during bale storage. Three moisture levels (15–20%, 20–25%, 25–30%) and three bale masses (13 kg, 18 kg, 24 kg, at an equal volume) were tested in varieties Pioneer and Alimba ‐ the most common cultivars in the Arabian Gulf region. Variety Alimba has a rougher texture with more stems and fewer leaves. This caused significantly higher water retention and consequently higher bale temperatures. In summer, bale temperatures of Alimba stored at 25–30% moisture content and 24 kg bale mass averaged 37.7°C compared with 28·2°C in variety Pioneer. Lowest dry‐matter (DM) content was 793 g kg−1 and was recorded in the winter cut of variety Alimba baled at the upper moisture level (25–30%), whereas the highest was that of variety Pioneer. Lowest crude protein content was that of variety Pioneer (61 g kg DM−1). Prolonged heat build‐up of some bales caused dark‐brown discoloration, and, although colour variations were significant, they were not large. There was no contribution of bale mass to changes in DM content, indicating that the selected levels of bale mass in the experiment were lower than those expected to cause significant effects on hay chemical composition and nutritive value. In general, it is recommended to store Rhodes grass hay at moistures up to 30% and even higher in the summer season in the case of variety Alimba. Higher moisture contents at baling could preserve hay quality by minimizing shattering of leaves excessively dried under the prevailing hay‐making conditions, especially in the variety Pioneer.
Effects of continuous sheep stocking and strategic rest periods on the sward characteristics of binary perennial grass/white clover associations
Authors: GOODING R. F. , FRAME J.
Published: April 2006

Five binary perennial grass/white clover (Trifolium repens, cv. Menna) mixtures were evaluated over a 3‐year period under continuous sheep stocking together with the imposition of a rest period for either an early or a late conservation cut; the experiment with plot sizes of 0·16 ha was replicated three times. The grass species and cultivars used were Merlinda tetraploid and Magella diploid perennial ryegrass (Lolium perenne), Prairial cocksfoot (Dactylis glomerata), Rossa meadow fescue (Festuca pratensis) and Goliath timothy (Phleum pratense). The greatest total lengths of white clover stolon developed in the meadow fescue (171·6 m m−2) and timothy (151·9 m m−2) associations compared with those in tetraploid perennial ryegrass (98·6 m m−2), diploid perennial ryegrass (91·9 m m−2) and cocksfoot (74·6 m m−2) (s.e.d. 16·4, P < 0·001). On average, the proportion of white clover stolon that was buried was between 0·86 and 0·89 and this was more abundant in late than early season. Whereas timothy persisted, the persistence of meadow fescue was low under any of the managements tested and this was markedly reduced by the third grazing season. In the diploid perennial ryegrass sward, a late June to early August rest period for conservation enhanced white clover stolon length. An early April to late May rest period greatly reduced total white clover stolon length in both diploid perennial ryegrass and tetraploid perennial ryegrass associations (diploid perennial ryegrass‐unrested 89 m m−2, early rest 56·1 m m−2, late rest 130·7 m m−2; tetraploid perennial ryegrass ‐ unrested 125·1 m m−2, early rest 71 m m−2, late rest 99·7 m m−2; s.e.d. 19·19, P < 0·001). The numbers of white clover stolon growing points per unit stolon length were greatest when the sward was rested during late June to early August −55·9 m−1 stolon length compared with 45·7 m−1 for an April to late May rest and 46 m−1 in the absence of a rest (s.e.d. 2·59, P < 0·001). Likewise, the percentage of stolon above ground was greatest with the late June to early August rest −15·78% compared with 10·61% for the April to late May rest and 7·69% for no rest (s.e.d. 1·569, P < 0·001). The complementary percentages of buried stolon indicate the important role this fraction has and the need to study stolon behaviour in grazing studies generally. It is concluded that, in relation to perennial ryegrass as a companion grass, meadow fescue and timothy allow better white clover development and cocksfoot less. However, other attributes have to be considered, for example the poor persistence of meadow fescue and the slower regrowth of timothy, both of which allow the invasion of weed grasses, or the lower acceptability of cocksfoot to livestock. The timing of the rest period before the conservation cut can influence white clover development considerably, but the effects differed with different companion grasses.
The importance of water‐soluble carbohydrate reserves on regrowth and root growth of Lolium perenne (L.)
Authors: DONAGHY D. J. , FULKERSON W. J.
Published: April 2006

This glasshouse study aimed to determine the relative importance of water‐soluble carbohydrates (WSC) and current photosynthate on root and top regrowth of perennial ryegrass (Lolium perenne L.). Individual plants were arranged in one of two miniswards (Experiments 1 and 2) and underwent varying defoliation frequencies designed to obtain a gradient of WSC content at the final harvest of each treatment (H1), when all treatments were defoliated. In Experiment 1, the plants were defoliated either three times at the one new leaf per tiller stage of regrowth (treatment 3 × 1), once at the two‐leaf and again at the one‐leaf stage (treatment 2, 1), once at the one‐leaf and again at the two‐leaf stage (treatment 1, 2) or once only at the three‐leaf stage (treatment 1 × 3), up to H1. Leaf and root growth and other parameters were assessed over 6 d after H1 in sunlight, and over a 4‐week period in darkness, and related to initial plant WSC content. In Experiment 2, plant defoliation treatments were: 3 × 1, 1, 2 or 1 × 3. Leaf regrowth was assessed for 36 d until the plants had three fully expanded new leaves per tiller.

Leaf regrowth in both experiments was significantly related to stubble WSC (below 50 mm height).

In Experiment 1, plants were almost fully reliant upon plant reserves for the first 3 d of regrowth, with reliance decreasing up to 6 d. When regrowth of plants was compared after 1 week in light or in darkness, it was estimated that one‐third of leaf regrowth was due to plant WSC reserves and the remainder due to photosynthesis. However, the capacity to photosynthesize and to grow roots after H1 was also significantly related to stubble WSC content.

In Experiment 2, there was a significant difference (P<0·01) between defoliation treatments on leaf dry matter (DM) yield at 12 d (×1 leaf tiller−1) of regrowth, and this was, as in Experiment 1, significantly positively related to WSC content in the stubble. However, after 36 d of regrowth, DM yield of plants defoliated at 2 or 3 leaves tiller−1 up to H1 were similar, and both were significantly higher (P<0·01) than regrowth of plants defoliated at the one‐leaf stage.

After defoliation, the period of reliance on WSC reserves may be substantially increased in situations of shading (canopy competition or cloud cover) or if the new regrowth shoot is removed by regrazing.
In vitro digestibility of green lamina of cocksfoot (Dactylis glomerata L.) in relation to water deficit
Authors: DUCROCQ H. , DURU M.
Published: April 2006

The effect of water deficit on in vitro dry‐matter digestibility (IVDMD) of green lamina of cocksfoot (Dactylis glomerata) was investigated over a 6‐week period following a cut. Two levels of water deficit were compared with a well‐irrigated sward. The leaf water potentials were –10·3, –7·6, –1·9 bars, respectively, for the three treatments. For the last 25 d of the regrowth period, the IVDMD of green laminae decreased significantly faster on the well‐watered (–0·11) than on the treatments that were subjected to a water deficit (from –0·036 to –0·068). This difference was associated with a smaller drop in the leaf appearance rate and a greater increase in the length of the successively emerging leaves on the well‐watered than on the two water‐stressed treatments. Overall, the IVDMD showed greater correlation with the average leaf insertion level on a tiller than the sampling date. In the range of water stress observed, the IVDMD increased in relation to a delay of the normal onto‐genetical drift.
Datailed surveying and mapping of plant communities on featureless terrain
Authors: GOODING R. F. , RACKHAM D. , HOLLAND J. P. , ROBERTSON D.
Published: April 2006

A system of detailed vegetation mapping has been developed for use on undulating terrain where there is a complex mosaic of soil types, drainage characteristics and plant communities and where topography is such that it is impossible to locate a position by reference solely to a map grid reference point, for example hill/moorland grazings, sand dunes and mud flats. The system involved using electronic surveying equipment to locate accurately, in terms of National Grid coordinates and altitude, a large number of points over the area to be surveyed for which vegetation types were identified and recorded. The merged location and vegetation data set for individual points were imported into a geographic information system (GIS) to map ‘point’ vegetation data accurately. The GIS was then used to create regions around points (voronoi) using Delaunay triangulation to produce a vegetation map. Altitude information was used within the GIS to produce a contour map of the surveyed area.

Vegetation was classified into communities of the British National Vegetation Classification and, although it does not describe all the variants within communities/sub‐communities fully, extra information for individual point locations was stored in tables within the GIS. This information was readily accessed by using the mouse cursor to highlight a point and reveal a window containing all the tabulated information for that point.

This methodology was used to produce a reliable map that accurately positioned and mapped previously unmarked landscape features, new boundaries/fences, vegetation types and contours. This facility could be used for a variety of experimental, planning and consultancy applications including botanical survey work, grazing behaviour studies, conservation, land use planning and management.
Simulation of allocation of accumulated biomass to leaf and stem in a grass growth model
Authors: WU L. , MCGECHAN M. B. , KNIGHT A. C.
Published: April 2006

To model variations in leaf/stem ratio in connection with studies of field‐drying of grass, account was taken of the effects that the stage of morphological development of grass has on the allocation of biomass to plant components, as well as on duration of growth and peak yield. A comparison of experimental data and corresponding daily weather data suggested that it is more satisfactory to express the stages of grass development in terms of degree‐days than time alone. On the basis of one set of weekly measured data, the ratio of green leaf weight to aboveground biomass was found to be a close fit to a positive linear relationship early in the growth period (durïng expansion of the first leaf on each tiller), followed by negative exponential relationship (during expansion of subsequent leaves), in relation to relative development expressed as growing degree‐days. Similar trends, but with some quite large variations in absolute values because of unknown factors, were found in two other datasets consisting of a few measurements only.
The pharmacokinetics of coagulation factors
Authors: LEE M. , MORFINI M. , NEGRIER C. , CHAMOUARD V.
Published: April 2006

Summary.  In this article, we provide a summary of the generally accepted approaches to the design and analysis of studies examining the pharmacokinetic (PK) profile of an infused coagulation factor in patients with a deficiency of one or more of these factors. Furthermore, we briefly review the known PK results for various commercially available coagulation factor preparations under single and continuous infusion.
Haemophilia and ageing
Authors: STREET A. , HILL K. , SUSSEX B. , WARNER M. , SCULLY M‐F.
Published: April 2006

Summary.  Men with haemophilia have not only the challenges of living with HIV and/or HCV infection and premature arthritis as complications of their disorder, but they also confront the other ails of ageing. These include genitourinary problems such as prostatic hypertrophy, prostatic cancer and renal stone disease, and arterial disease for which haemophilia is not protective. Progressive arthritis and declining fitness may lead to loss of independence which causes great concern. Associated with the physical aspects of ageing, many patients also suffer from psychological symptoms which may be precipitated by changes in work such as early retirement and altered family dynamics. Many older men with haemophilia may never have consulted primary care physicians because of the rarity and complexity of their disorder. Haemophilia centre staff often assume responsibility for the identification and management of all health problems of their patients. Even when other clinicians are involved, patients require their centre's involvement in the investigation and support of many procedures such as coronary artery surgery and urological surgery. This paper addresses falls in the older man with haemophilia, their causes and consequences and cardiovascular problems in particular. Very little literature has been published about these common problems. We need to be aware of the ageing issues in haemophilia and develop ‘wellness’ programs which are directed to the early identification of disease as well as preventative strategies to reduce the physical and psychological impacts of ageing.
The natural evolution of haemophilia care: developing and sustaining comprehensive care globally
Authors: EVATT B. L.
Published: April 2006

Summary.  Comprehensive care is vital for patients with haemophilia to prevent early death and free patients from the complications that inhibit living normal lives. Experience has shown that once introduced in a country, there is a progressive restoration of normal healthy lives to the haemophilia community. Accompanying this progress is a gradual decreased dependency on the haemophilia comprehensive centre – except during brief periods when expertise contained within the comprehensive centre is mandatory for life‐saving clinical management or to prevent severe morbidity. During each stage of the natural evolution of comprehensive haemophilia care in a country, challenges to the existence of the centre occur, which threaten the comprehensive treatment concept. The haemophilia community must understand this natural evolution and be prepared to work collaboratively with governments, physicians and other patients to ensure that centres retain the expertise to meet the emergent needs when they arise.
Ethical issues in haemophilia
Authors: DIMICHELE D. , CHUANSUMRIT A. , LONDON A. J. , THOMPSON A. R. , COOPER C. G. , KILLIAN R. M. , ROSS L. F. , LILLICRAP D. , KIMMELMAN J.
Published: April 2006

Summary.  Ethical issues surrounding both the lack of global access to care as well as the implementation of advancing technologies, continue to challenge the international haemophilia community. Haemophilia is not given the priority it deserves in most developing countries. Given the heavy burdens of sickness and disease and severe resource constraints, it may not be possible to provide effective treatment to all who suffer from the various ‘orphan’ diseases. Nevertheless, through joint efforts, some package of effective interventions can be deployed for a significant number of those who are afflicted with ‘orphan’ diseases. With cost‐effective utilization of limited resources, a national standard of care is possible and affordable. Gene‐based diagnosis carries attendant ethical concerns whether for clinical testing or for research purposes, even as the list of its potential benefits to the haemophilia community grows rapidly. As large‐scale genetic sequencing becomes quicker and cheaper, moving from the research to the clinic, we will face decisions about the implementation of prenatal, neonatal and other screening programs. Such debates will require input from not just the health care professionals but from all stakeholders in the haemophilia community. Finally, long‐term therapeutic success gene transfer in small and large animal models raises the question of when and in which patient population the novel therapeutic approach should first be studied in humans with haemophilia. Although gene therapy represents a worthy goal, the central question for the haemophilia community should be whether it wishes to volunteer itself as a model for a much broader set of innovations.
Strategies towards a longer acting factor VIII
Authors: SAENKO E. L. , PIPE S. W.
Published: April 2006

Summary.  The reduced mortality, improved joint outcomes and enhanced quality of life, which have been witnessed in the developed world for patients with haemophilia, have been an outstanding achievement. Advancements in biotechnology contributed significantly through the development of improved pathogen screening, viral inactivation techniques and the development of recombinant clotting factors. These were partnered with enhanced delivery of care through comprehensive haemophilia centres, adoption of home therapy and most recently effective prophylaxis. This came at great costs to governments, medical insurers and patients’ families. In addition, barriers persist limiting the adoption and adherence of effective prophylactic therapy. Biotechnology has been successful at overcoming similar barriers in other disease states. Long‐acting biological therapeutics are an incremental advance towards overcoming some of these barriers. Strategies that have been successful for other therapeutic proteins are now being applied to factor VIII (FVIII) and include modifications such as the addition of polyethylene glycol (PEG) polymers and polysialic acids and alternative formulation with PEG‐modified liposomes. In addition, insight into FVIII structure and function has allowed targeted modifications of the protein to increase the duration of its cofactor activity and reduce its clearance in vivo. The potential advantages and disadvantages of these approaches will be discussed.
Tissue engineering in musculoskeletal problems related to haemophilia
Authors: CAVIGLIA H.
Published: April 2006

Summary.  This article is a review of how advances in tissue engineering can be applied to the musculoskeletal pathology of patients with haemophilia. This article will also explain the theory that the deterioration of joints in patients with haemophilia is due to biological and mechanical causes.

Current concepts of tissue engineering would be to replace the degenerated and damaged tissue by live cells, using them as a biological implant. However, before these new technologies are applied, an appropriate control of their indication and results is required.
Rare bleeding disorders
Authors: PEYVANDI F. , KAUFMAN R. J. , SELIGSOHN U. , SALOMON O. , BOLTON‐MAGGS P. H. B. , SPREAFICO M. , MENEGATTI M. , PALLA R. , SIBONI S. , MANNUCCI P. M.
Published: April 2006

Summary.  Deficiencies of coagulation factors other than factor VIII and factor IX (afibrinogenemia, FII, FV, FV+FVIII, FVII, FX, FXI, FXIII) that cause bleeding disorders (RBDs) are inherited as autosomal recessive traits and are rare, with prevalences in the general population varying between 1 in 500.000 and 1 in 2 million for the homozygous forms. As a consequence of the rarity of these deficiencies, the type and severity of bleeding symptoms, the underlying molecular defects, and the actual management of bleeding episodes are not as well established as for hemophilia A and B. The study of the genetic basis of these disorders could represent an important tool for prevention through prenatal diagnosis. Treatment of patients with RBDs during bleeding episodes or surgery is a challenge because of the lack of experience and the paucity of data. For some deficiency factor concentrates are still non available and severe complications can occur. These complications can be minimized by assessment of risks of bleeding and thrombosis, use of haemostatic means other than blood components or no therapy at all. The RBDs pose a problem for guideline writers because there are no suitable clinical trials to supply good evidence for how these people are best treated. The lack of adequate information on clinical manifestations, treatment and genetic basis of RBDs could be improved by the collection of data in an International Database (http://www.rbdd.org), linkable to others previously published. This could be a useful tool to fill the gap between clinical data and clinical practice. This article reviews the genetic basis of RBDs, problems and complications of treatment, problems in the preparation of suitable guidelines for treatment and the future perspectives of the International Registry on RBDs.
Laboratory issues in bleeding disorders
Authors: LILLICRAP D. , NAIR S. C. , SRIVASTAVA A. , RODEGHIERO F. , PABINGER I. , FEDERICI A. B.
Published: April 2006

Summary.  The clinical history of the patient and of his/her relatives is the most important tool for making correct diagnosis of inherited or acquired bleeding disorders. Several attempts have been made by clinicians to evaluate the sensitivity and specificity of bleeding symptoms. Specific and detailed questionnaires have been designed to quantify the bleeding tendency of patients with von Willebrand's disease (VWD) and a bleeding score has been calculated. VWD is considered the most frequent inherited bleeding disorder according to population studies: however, due to the complexity of its diagnosis, the number of patients with correct diagnosis of VWD in many developing countries is relatively low and most cases remain still under‐ or misdiagnosed. Once bleeding history is carefully evaluated by means of a bleeding score, the laboratory workout should be organized to find out the specific defect of haemostasis responsible for bleeding. Since factors involved in haemostasis are many, the correct approach must include first level screening tests with the aim to identify the abnormal phase of haemostasis involved: then, second level tests should be focused on the specific factors within the abnormal step of haemostasis. Among many other acquired bleeding disorders related to clinical conditions or to the use of drugs, the acquired inhibitors of haemostasis are rare but should be immediately characterized by appropriate laboratory tests because they can be often life‐threatening for the patients.
Flow cytometric evaluation of selected antimicrobial efficacy for clearance ofAnaplasma marginalein short‐term erythrocyte cultures
Authors: COETZEE J. F. , APLEY M. D. , KOCAN K. M. , JONES D. E.
Published: April 2006

The tick‐borne rickettsia,Anaplasma marginale, causes the economically important cattle disease anaplasmosis. Once infected, cattle remain lifelong carriers. Herein, we used flow cytometry to test the efficacy of three antimicrobials; oxytetracycline, imidocarb and enrofloxacin against Virginia (VGN) or Oklahoma (OK)A. marginaleisolates in short‐term erythrocyte cultures. Parasite viability was assessed using the vital dye hydroethidine (HE), which is detectable when living organisms convert HE to ethidium bromide. Viability ofA. marginalein selected cultures was determined by subinoculation into susceptible calves. Data were analyzed by MANOVA, Tukey‐Kramer honest significant difference and Wilcoxon rank sum tests. Receiver operating characteristic (ROC) analysis was used to correlate results with culture infectivity. Enrofloxacin inhibitedA. marginalein a dose dependent manner. Surprisingly, higher concentrations of imidocarb were less effective than lower concentrations againstA. marginalewith significant differences (P < 0.05) observed between the two isolates. Oxytetracycline was the least active drug tested. Cultures infected with the OK isolate exposed to 4.0 μg/mL enrofloxacin and those of the VGN and OK isolates exposed to 1.0 μg/mL imidocarb were sterilized. This is the firstin vitrostudy demonstrating the efficacy of enrofloxacin againstA. marginale. Furthermore, these data indicate that flow cytometry is a useful assay for screening antimicrobials againstA. marginale.
Lupus erythematosus tumidus: a series of 26 cases
Authors: Vieira Vanessa , Del Pozo Jesús , Yebra‐Pimentel Maria Teresa , Martínez Walter , Fonseca Eduardo
Published: April 2006

Objective  To study 26 cases of lupus erythematosus tumidus (LET), a subset of chronic cutaneous lupus erythematosus (CCLE), referred to in the literature as a rare entity.

Patients and methods  A retrospective study was conducted of 26 patients diagnosed with LET between 1996 and 2002. The clinical characteristics, histopathologic and laboratory findings, response to treatment, association with other subsets of lupus, course, and diagnostic criteria were analyzed.

Results  The incidence by sex was similar. The mean age of presentation was 49.19 years. The clinical presentation usually involved erythematous, edematous plaques located on the face, chest, back, or extremities, related to sun exposure. A dermal lymphocytic infiltrate with a perivascular disposition and differing degrees of mucin deposition was observed in all cases. Minimal epidermal changes were present in 18 cases, and 11 of these also showed minimal dermal–epidermal changes. Only one case showed dermal–epidermal changes without any epidermal alteration. Direct immunofluorescence test was performed in 15 patients, and 11 were negative. All cases showed a benign course without systemic manifestations. The response to topical steroids or antimalarial treatment was excellent, but a seasonal recurrence was usually observed.

Discussion  No defined criteria for LET are universally accepted. The main controversies are the acceptance of LET as a separate subset of CCLE, and the histopathologic diagnostic features, mainly the presence or absence of epidermal and dermal–epidermal changes in these lesions.

Conclusions  No inflexible histologic criteria should be employed for the diagnosis of LET. This subset of lupus erythematosus is characterized by intense photosensitivity, definite clinical lesions, a benign course, the absence of systemic disease, good response to antimalarial treatment, and a tendency to recur. More studies should be performed in order to establish the true incidence of LET because this subset of CCLE is probably underestimated.
Quantification of blood intake of the head louse: Pediculus humanus capitis
Authors: Speare Rick , Canyon Deon V. , Melrose Wayne
Published: April 2006

Although head lice, Pediculus humanus capitis, are globally prevalent blood‐sucking ectoparasites, the amount of blood imbibed by head lice has not been determined. This study investigated this parameter, as regular loss of a small quantity of blood may lead to an iron deficiency and anaemia. Adult female lice (66), adult males (46), and nymphs (152) were weighed before and after feeding in groups of 17–109 lice. The average amounts of blood imbibed at a single feed were: adult female louse (0.0001579 ml), adult male (0.0000657 ml) and nymph (0.0000387 ml). Assuming three feeds per day by an average infection of 30 lice (10 females, 10 males, and 10 nymphs), the average child with active pediculosis would loose 0.008 ml of blood per day. This amount of blood loss is of no clinical significance even in iron‐deficient children. The most heavily infected child observed with 2657 lice could be expected to loose 0.7 ml/day or 20.8 ml/month, which may be of clinical importance in a child on an adequate diet, and would be significant in an iron‐deficient child. However, if head lice feed more often than three times a day, a heavy infestation would have a greater potential to lead to iron deficiency. The frequency of feeding of head lice on the head of the human host needs to be determined.
POST CAESAREAN VESICOUTERINE FISTULAE – YOUSSEF SYNDROME: OUR EXPERIENCE AND REVIEW OF PUBLISHED WORK
Authors: Rao M. Prasad , Dwivedi U. S. , Datta B. , Vyas N. , Nandy P. R. , Trivedi S. , Singh P. B.
Published: April 2006

Objective:  To analyse the incidence, symptomatology, diagnosis and therapeutic aspects of Youssef syndrome (post caesarean vesicouterine fistula), and to review relevant published work.

Methods:  A retrospective study from the urosurgical unit of a tertiary care referral hospital was carried out. In a retrospective analysis of urogenital fistulae over 10 years, we identified 14 patients with uterovesical fistulae, resulting from caesarean section. All the patients were evaluated by history, physical examination, radiological tests and cystoscopy. All patients underwent transperitoneal repair of these fistulae with omental interposition. Results of surgery were evaluated by absence of cyclic haematuria, stoppage of urinary incontinence, and achievement of fertility.

Results:  A total of 12 patients who had minimum follow up was included in the present study. The results showed that 50% of the fistulae resulted from emergency caesarean operation with 58% of patients presenting after their second caesarean section. The mean age of the patients was 19 years (range 15–29) and mean duration of symptoms was 7 months (range 3–16). Menouria and amenorrhoea were predominant presenting symptoms. The results of surgical treatment were excellent with good continence and resolution of the cyclic haematuria. Three pregnancies (37.5%) which resulted in elective caesarean section were recorded.

Conclusion:  Vesicouterine fistulae, despite being infrequent, are no longer a rare diagnosis and are most commonly secondary to lower segment caesarean section. With patient history and selected investigations diagnosis is relatively easy. The surgical repair of these fistulae is standard treatment, especially with delayed fistulae with achievement of total continence, and complete resolution of cyclic haematuria. Meticulous practice of obstetric and surgical principles during caesarean section can prevent the formation of these fistulae.
HEPATECTOMY FOR METASTATIC NONCOLORECTAL GASTROINTESTINAL, BREAST AND TESTICULAR TUMOURS
Authors: Metcalfe Matthew S. , Mullin Emma J. , Maddern Guy J.
Published: April 2006

Background:  The indications for hepatectomy for colorectal or neuroendocrine metastases are becoming clear with increasing experience reported. For other primary diseases, however, the overall number of cases is relatively small, and it is more difficult to derive clear guidelines. This paper reviews the reported experience of hepatectomy for metastases from non‐colorectal gastrointestinal primary cancers, breast cancer and testicular teratoma. The aim is to determine for each whether and under what circumstances hepatectomy is indicated.

Methods:  A Medline search was used to identify papers reporting hepatectomy for metastases from non‐colorectal gastrointestinal carcinomas, breast carcinomas and testicular teratomas. The data collected included the primary disease, the number of cases reported, the survival post‐hepatectomy and any prognostic factors associated with outcome.

Results:  Of the gastrointestinal malignancies, hepatectomy for gastric metastases yields a 5‐year survival, roughly half that reported for colorectal disease, and further elucidation of prognostic factors would be desirable. Results were poor for other gastrointestinal malignancies. Good results were reported for breast and testicular teratoma.

Conclusion:  Of the non‐colorectal gastrointestinal primaries, at present only hepatectomy for gastric metastases can be cautiously recommended. For nongastrointestinal primaries, hepatic metastases probably represent widespread dissemination even if occult, and therefore, hepatectomy may only be of use when effective adjuvant treatments are available.
OPTIMIZATION OF OUTCOME AFTER LAPAROSCOPIC ANTIREFLUX SURGERY
Authors: Hayden Jeremy D. , Jamieson Glyn G.
Published: April 2006

Laparoscopic fundoplication has emerged as an effective treatment for gastro‐oesophageal reflux disease. The majority of patients who have undergone antireflux surgery report an improvement in reflux symptoms and in quality of life. However, some patients are dissatisfied with the outcome of antireflux surgery, and attempts have been made by surgeons to improve the results of this surgery. Careful case selection based on objective evidence of acid reflux, refinement of the surgical technique and ‘tailoring’ the wrap to suit the patient by selective use of a partial fundoplication may help to optimize the outcome from laparoscopic antireflux surgery.
Welfare Economics with Intransitive Revealed Preferences: A Theory of the Endowment Effect
Authors: CARMICHAEL H. LORNE , MACLEOD W. BENTLEY
Published: April 2006

Economists use the standard rational model to predict behavior after a policy change and to determine the policy's welfare implications. Recent experimental observations are casting doubt on the predictive accuracy of the standard model, but the more realistic behavioral alternatives often provide a poor basis for making normative evaluations. This paper suggests that we can still predict behavior and measure welfare within the same model. We show that optimizing agents with standard preferences will in some cases behave as if they are subject to an endowment effect. Even so, we may still be able to uncover information about their preferences.
Effort and Performance in Public Policy Contests
Authors: EPSTEIN GIL S. , NITZAN SHMUEL
Published: April 2006

Government intervention often gives rise to contests in which the possible “prizes” are determined by the status quo and some new public policy proposal. In this paper we study a general class of such two‐player public policy contests and examine the effect of a change in the proposed policy, a change that may affect the payoffs of the two contestants, on their effort and performance. Our results extend the existing comparative statics studies that focus, in symmetric contests, on the effect of a change in the value of the prize or, in asymmetric contests, on the effect of one contestant's valuation of the prize. Our results hinge on a fundamental equation that specifies the equilibrium relationship between the strategic own‐stake effect and the strategic rival's‐stake effect. This fundamental equation clarifies the role of the three possible types of ability and stake asymmetry in determining the effect of payoff variations on the efforts and performance of the contestants.