bluuebunny/crossref_metadata_2025 huggingface dataset:
Haemophilic synovitis: is rifampicin an alternative?
Authors: Lee C. A. , Kessler C. M. , Varon D. , Martinowitz U. , Heim M. , CAVIGLIA H. , GALATRO G. , DUHALDE C. , PEREZ‐BIANCO R.
Published: March 2003

Summary. Rifampicin synoviorthesis has been empirically used for the treatment of haemophilic synovitis for some time. This paper reports on the experience of three Latin American centers with this treatment and compares it with radioactive synoviorthesis results. Chemical synoviorthesis with rifampicin is best indicated in younger patients (<15 years) and small joint (ankles and elbows).
Muscle rehabilitation in haemophilia
Authors: Lee C. A. , Kessler C. M. , Varon D. , Martinowitz U. , Heim M. , BEETON K. , CORNWELL J. , ALLTREE J.
Published: March 2003

Summary. Musculoskeletal dysfunction is a common manifestation of haemophilia. This dysfunction may be associated with imbalances between muscle groups. Evidence emerging from the literature suggests that the rehabilitation of this dysfunction is very relevant for the patient with musculoskeletal problems. Treatment of muscle imbalance may be linked with a reduction in recurrence of symptoms. Further research is needed to establish the relevance of this area in patients with haemophilia but the clinical evidence supports the developing work in this field.
A retrospective study on chemical and radioactive synovectomy in severe haemophilia patients with recurrent haemarthrosis
Authors: MOLHO P. , VERRIER P. , STIELTJES N. , SCHACHER J.‐M. , OUNNOUGHÈNE N. , VASSILIEFF D. , MENKES C.‐J. , SULTAN Y.
Published: March 2003

Between 1970 and 1994, 116 chemical and 90 radioactive synovectomies were performed in 107 patients with severe haemophilia and two with type 3 von Willebrand's disease. The products used were osmic acid (OA) in 100 cases, 90‐Yttrium in 35 cases, 186‐Rhenium in 48, 169‐Erbium in two, hexacetonide triamcinolone in 16 and radioactive gold in five cases. The use of radioactive colloids is not allowed in France in patients under 15 years of age. Twenty‐nine patients had more than one synovectomy per joint. All patients were evaluated for 6 months post‐synovectomy, using both a clinical and a radiological score. Six months after synovectomy, a good or excellent result was obtained for 81% of the joints treated with isotopes, compared with 44% of those treated with OA, P < 0.001. This superiority of isotopes over osmic acid was still observed after 6 months for the 89 joints that were re‐evaluated, with follow‐up ranging from 1 to 9 years. It was possible to calculate a radiological score in 84 cases. With OA the best results were from the joints with the lowest scores pre‐synovectomy (<7). No correlation could be established between the clinical and the radiological scores, due to the small size of the sample. In summary: (1) chemical and radioactive synovectomy are simple and safe procedures for haemophilic arthropathy, (2) in our series, after 6 months the efficacy of isotopic synovectomy was greater than that of chemical synovectomy, and this benefit seems to persist after 6 months, and up to 9 years in the group of patients with longer‐term follow‐up.
Safety and efficacy of three arthroscopic procedures using Holmium: Yag laser in two high‐responder haemophiliacs
Authors: Ménart  , Lalain  , Lienhart  , Dechavanne  , Négrier
Published: March 2003

We report here on the efficacy and safety of three arthroscopic procedures using a Holmium: Yag laser in two high‐responder haemophiliacs. The two patients were treated with an activated prothrombin complex concentrate (FEIBA; Immuno, Vienna, Austria). Treatment was started just before surgery and continued for 4–8 days. On one occasion antifibrinolytics were concomitantly used without thromboembolic complication. Post‐operative blood loss was slight, joint mobility was rapidly acceptable and full weight bearing without pain was possible on day 4. Such a procedure would appear to be superior to conventional arthroscopic synovectomy utilizing mechanical devices in haemophiliacs, because it might improve the quality of local haemostasis and the rapidity of post‐operative recovery. In addition, it is also the technical procedure of choice in haemophilic patients with inhibitors who need synovectomy.
Common orthopaedic problems in haemophilia
Authors: Rodriguez‐Merchan E.C.
Published: March 2003

The most important fact in patients with haemophilia is the avoidance of recurrent haemarthroses by means of haematological prophylaxis. Unfortunately this is not currently possible in the majority of countries around the world. When only on‐demand haematological treatment is available, frequent evaluations are necessary for the early diagnosis and treatment of intra‐articular bleeding episodes. The typical outcome of these patients is towards the development of chronic synovitis, and later on to haemophilic arthropathy, if the state of synovitis is not promptly and adequately controlled. Once arthropathy develops the functional prognosis is poor, although haemophilic patients use to tolerate very well their tremendous joints destructions. Treatment of these patients should be performed in a comprehensive basis within a multidisciplinary haemophilia unit.
Loss of factor VIII activity during storage in PVC containers due to adsorption
Authors: Mcleod  , Walker  , Zheng  , Hayward
Published: March 2003

Recombinant factor VIII concentrates are stable when administered in a reconstituted form according to the manufacturer’s specifications, and undiluted via infusion with syringe mini‐pumps. However many Haemophilia centres administer recombinant factor VIII further diluted in intravenous fluids for greater ease of administration. To investigate the stability of recombinant factor VIII during administration as a diluted infusion, reconstituted factor VIII was stored in polyvinylchloride (PVC) mini‐bags undiluted (146 IU mL–1) and at factor VIII concentrations of 10 IU mL–1 and 2 IU mL–1. After 48 h of storage at room temperature in PVC mini‐bags, the recoveries of factor VIII activity were 41.9% of the initial activity for the undiluted (146 IU mL–1) product and 43.7% of the initial activity for factor VIII diluted to 10 IU mL–1. For factor VIII diluted to 2 IU mL–1, the amount of factor VIII activity remaining at 48 h was only 1.8% of the initial activity. In contrast, 100% of factor VIII activity was recovered after 48 h when undiluted reconstituted product (146 IU mL–1) was stored in a syringe. To investigate the mechanism of factor VIII activity loss during storage, factor VIII samples collected after 0, 3 and 48 h of storage were analysed by immunoblotting with factor VIII antibodies. No evidence of factor VIII proteolytic degradation during storage was found, however, large amounts of factor VIII antigen were recovered from the empty PVC mini‐bags following elution with denaturing detergent. We conclude that clinically significant losses of factor VIII activity occur during storage in PVC mini‐bags and that the loss of activity is most likely due to protein adsorption onto the plastic surface. This loss of factor VIII activity during storage in PVC containers may substantially affect the safety and potential cost savings of administering recombinant factor VIII by continuous infusion.
Elbow joint, crutches and locomotion: special reference to persons with haemophilia
Authors: Heim  , Wershavski  , Martinowitz  , Chechick  , Azaria
Published: March 2003

A 52‐year‐old, trans‐femoral amputee with haemophilia was hospitalized because of ambulatory problems arising from the osteo‐arthropathic involvement of other major articulations. Reduced function in the upper limbs, caused by the effects of recurrent haemarthroses, resulted in additional problems concerning the usage of auxiliary ambulatory aids. The advantages and disadvantages of traditional and experimental crutches highlight the functional problems of ambulation in persons with concomitant upper limb pathologies.
Total joint arthroplasty in haemophilia
Authors: Beeton  , Rodriguez‐Merchan  , Alltree
Published: March 2003

In severely affected haemophilic patients arthropathy is a common problem which can lead to considerable pain and functional deficit. Surgical management, including total joint arthroplasty, can be undertaken if conservative management fails. A search of the literature showed that a number of studies describing the use of total knee arthroplasty (TKA) and total hip arthroplasty (THA) in haemophilia have been published, whereas shoulder, elbow and ankle arthroplasties are confined to case reports. This paper reviews the functional outcome of arthroplasty in the different joints, the postoperative and long‐term complications, and the impact of HIV. Although complications are commonly described and the surgery is technically demanding, the results suggest that arthroplasty, particularly of the hip and knee, can be a valuable option in the management of severe haemophilic arthropathy.
Use of ristocetin cofactor activity in the management of von Willebrand disease
Authors: Ewenstein B.M.
Published: March 2003

von Willebrand disease (vWD), the most common of the hereditary bleeding disorders, arises from quantitative or qualitative defects in von Willebrand factor (vWF). vWF is a multimeric plasma protein that plays a key role in primary and secondary haemostasis. In the current classification scheme, vWD is divided into six subtypes that are based on the nature of the vWF defect. Therapeutic strategies depend on the accurate identification of these subtypes. In most clinical situations, desmopressin is effective treatment for the great majority of patients with mild (type 1) disease, while replacement therapy with factor VIII/vWF concentrates that contain high levels of vWF activity is required for most type 2 and nearly all type 3 vWD patients. Several factor VIII/vWF replacement products are available, one of which (Humate P) has been approved for the treatment of vWD by the US Food and Drug Administration. Preliminary results of recent studies support the hypothesis that treatment with factor VIII/vWF concentrates based upon the content of vWF activity as reflected in the ristocetin cofactor assay is practicable, safe and efficacious. The establishment of optimal treatment regimens with respect to dose intensity and duration will require further study.
New‐generation recombinant factor concentrates: bridge to gene therapy
Authors: Ragni M.V.
Published: March 2003

Despite our best efforts to deceive the immune system, outwit pathogens, and improve upon the design of nature, there continues to be a need to improve the margin of safety of treatment for those with bleeding disorders. The current approach includes: (1) recombinant factor concentrates free of added proteins; (2) ‘designer’ factor molecules that enhance function and reduce immunogenicity; and (3) modulation of the immune system to suppress immune response in those who develop inhibitors. The hope is that through advances in our understanding of the coagulation and immune systems, treatment of haemophilia in the new millennium will be safer and less immunogenic. Currently available recombinant clotting factor concentrates include those produced: (1) with pasteurized human serum albumin in the cell culture medium as a stabilizer; (2) with bovine serum proteins in the cell culture medium; and (3) free of plasma derivatives. To the extent that current recombinant clotting factor concentrates contain even trace amounts of human or animal protein, there is continuing potential for transmission of nonenveloped viruses, including hepatitis A and parvovirus, and the theoretical potential for transmission of relatively unknown agents, such as prions (Creutzfeldt–Jakob disease or its variant). Second‐generation recombinant factor concentrates that do not use human albumin as a stabilizer are currently in clinical trials, and third‐generation recombinant factor concentrates currently in development take advantage of new strategies to achieve a ‘protein‐free’ cell culture, purification, and final formulation. It is likely that improvement in safety and reduction in immunogenicity will require modification not only of antigenic structure but also of the immune response to coagulation proteins.
Synoviorthesis with radioactive gold in haemophilia
Authors: Petersson C.J.
Published: March 2003

According to the experiences of the Malmö Haemophilia Centre, the best way to avoid recurrent joint bleedings and synovitis in haemophilic patients and to prevent progressive joint disease is prophylactic factor treatment. If prophylaxis is impracticable and also in patients with factor inhibitors, radioactive synoviorthesis seems to be a good treatment option if started early.
Prophylactic treatment of severe factor X deficiency with prothrombin complex concentrate
Authors: Kouides P. A. , Kulzer L.
Published: March 2003

Factor X (FX) deficiency is an autosomal recessive trait that occurs in fewer than 1 in 500 000 people. Not surprisingly, reports of prophylactic treatment for FX deficiency are exceedingly rare. We now report our experience of the use of prophylactic therapy in a FX‐deficient patient. This 18‐year‐old African‐American male presented at the age of 4½ years with an FX level < 1%. Treatment was on demand with prothrombin complex concentrates (PCCs) given at two times the dose per kilogram of body weight for factor IX. He experienced frequent epistaxis, soft tissue bleeding and joint bleeding. The development of a target joint (right ankle) prompted the initiation of prophylactic treatment in the beginning of 1998 to the present with 30 units kg−1 Profilnine twice per week via a home infusion programme. If breakthrough bleeding occurred, he was instructed to infuse another dose. He was instructed that Profilnine should not be infused in more than two doses in 24 h or on more than three consecutive days. A trough level drawn 48 h post‐infusion showed an FX level of 30%. In the initial 12 months with prophylactic treatment, there was no breakthrough bleeding. Subsequently, with an additional 11 months of follow‐up, he has reported one bleed. He rates his quality of life improved since starting prophylactic treatment. There have been no thrombotic events. Prophylaxis with PCC for FX deficiency with adequate education and follow‐up can be performed capably in the home setting with a resultant decrease in the frequency of bleeding and attendant complications.
Motor performance and disability in Dutch children with haemophilia: a comparison with their healthy peers
Authors: Schoenmakers M. A. G. C. , Gulmans V. A. M. , Helders P. J. M. , Van Den Berg H. M.
Published: March 2003

We investigated whether haemophilic children who are on prophylactic therapy differ from their healthy peers in terms of motor performance and disability. Thirty‐nine children, aged 4–12 years, with moderate (eight) and severe (31) haemophilia were included. Patients with severe haemophilia received primary prophylactic therapy that was individually tailored. The number of target joints, amount of swelling, range of motion, muscular strength and pain were measured, as well as motor skills and disability. The scores were compared to the normal population. No patients had target joints. Normal range of motion in all joints was seen in 97% (38/39) of the patients. Strength of elbow, knee, and ankle muscles were within the normal ranges. Ninety‐five percent (37/39) of the patients had normal motor performance. Although 90% of our patients (35/39) had no disabilities in activities of daily living (ADL), 79% (31/39) of them reported that the disease impacted on their lives. Seventy‐two percent (28/39) of the patients had pain, and in 21% (6/28) of them this was mainly caused by injections. Restrictions in sports or gymnastics were seen in 56% (22/39) of the patients. Those who indicated that they experienced pain and those who indicated restrictions in sports had a higher chance of experiencing disease impact compared to those who did not have these limitations. There were no significant differences between patients with moderate and severe haemophilia. In general, Dutch children with moderate or severe haemophilia are comparable with their healthy peers with regard to motor performance and ADL. However, a majority of the patients perceive an impact of their disease associated with pain and restrictions in sports.
Single‐dose pharmacokinetics of porcine factor VIII (Hyate C)
Authors: Hermans C. , Owens D. , Lilley P. , Longo G. , Morfini M. , Lee C.A.
Published: March 2003

The objective was to establish the pharmacokinetic properties of porcine factor VIII (pFVIII) at three different doses in a single patient. The patient, born in 1952, had severe haemophilia A and developed an inhibitor to human FVIII (hFVIII) in 1966 aged 14 years. He was first treated with pFVIII in 1980. Apart from a short period of treatment with hFVIII in 1998 which resulted in the reappearance of the inhibitor, pFVIII has been constantly used since 1984. No inhibitor against human or porcine FVIII had been recordable over the 2‐year period prior to the study. Three separate pharmacokinetic studies were performed using a washout period of 72 h and doses of 10 U kg−1, 25 U kg−1, or 50 U kg−1, respectively, with sampling at preinfusion, then at 15 and 30 min and 1, 3, 6, 9, 12 and 24 h postinfusion. The FVIII levels were measured using both plasma derived one stage APTT based assay and chromogenic assay. The results were computed using a model‐independent analysis and a model‐dependent analysis. The respective clearances (mL h−1 kg−1) at doses 50 U, 25 U or 10 U kg−1 were 1.32, 1.33 1.8 (bioassay) and 2.54, 2.93, 9.43 (chromogenic). The respective half‐lives (h) at doses 50 U, 25 U, and 10 U kg−1 were 23.71, 16.54, 25.17 (bioassay) and 15.71, 17.39, and 10.66 (chromogenic). The respective recoveries (u dL−1/u kg−1) at doses 50 U, 25 U, and 10 U kg−1 were 2.32, 2.44, 2.7 (bioassay) and 1.42, 1.16 and 0.9 (chromogenic). It was found that the two compartment model best fitted the curves of the bioassay and a one compartmental model best fitted the curves of the chromogenic assay. The pharmacokinetic studies are the first to be performed at different dose levels and using different assay methods for pFVIII. Using the bioassay, they show a long half‐life and high recovery compared to hFVIII. The differences between the bioassay and the chromogenic assay reflect their different biological basis and are of relevance when potency labelling is performed using chromogenic assay (European Pharmacopeia).
Progress in haemophilic care: ethical issues
Authors: BERNTORP E.
Published: March 2003

Care of haemophilic patients has dramatically improved during the past 40–50 years. Clotting factor concentrates have become much safer. Expensive treatments such as prophylaxis, immune‐tolerance induction, the use of bypassing agents in inhibitor patients, and the replacement of joints have become available. However, there is still a shortage of factor concentrate, and we are yet to discover the most cost‐effective treatment for patients. There is also a wide gap in the availability of these treatments between developing and developed countries, and a risk that patients are treated in unnecessarily expensive ways in some parts of the world compared with those who suffer from a lack of treatment in other parts, thus creating the ethical dilemma of whether less safe but more affordable concentrates should be used in developing countries. Other issues that raise ethical problems are the use of molecular genetics and gene therapy. It is proposed that international working groups, preferably under the auspices of the World Health Organisation and the World Federation of Hemophilia, take responsibility to solve the ethical issues in haemophilic care, the basis of which should be to promote the education of modern care and to set up clinical studies, including studies on health economics, so that treatment and care are cost‐effective and based on sound evidence.
Intra‐articular hyaluronic acid in the treatment of haemophilic chronic arthropathy
Authors: FERNÁNDEZ‐PALAZZI F. , VISO R. , BOADAS A. , RUIZ‐SÁEZ A. , CAVIGLIA H. , DE BOSCH N. BLUMENFELD
Published: March 2003

We report our preliminary experience with the use of hyaluronic acid (Synvisc®) in 29 joints from 25 different haemophilic patients (17 knees, six shoulders, four ankles, one elbow and one hip). All the joints were grade III of our classification, characterized by synovial thickening, axial deformities and muscle atrophy (chronic arthropathy). In view of the very satisfactory results obtained with this procedure, we have substituted Synvisc® for the previous use of intra‐articular long‐standing corticosteroids that we had been used for some years. This method is theoretically more physiological and does not destroy the joint cartilage further, as corticosteroids can.
Clinical and radiographic scores in haemophilic arthropathies: how well do these correlate to subjective pain status and daily activities?
Authors: Wallny T. , Lahaye L. , Brackmann H. H. , Heß L. , Seuser A , Kraft C. N.
Published: March 2003

Summary. Haemophilic patients who reached adulthood before the establishment of prophylactic treatment frequently show multiple and substantial arthropathies. The aim of this study was to determine to what extent haemophiliac's subjective impairment due to arthropathies correlates with objective clinical and radiographic parameters. By means of a questionnaire and a visual analogue scale, we consulted 79 haemophiliacs concerning their joint‐pain status, how these were treated and to what extent their daily activities had been affected. Using a scoring system suggested by the Advisory Committee of the World Federation of Haemophilia, clinical evaluation was performed. Radiographs of 60 patients were assessed by means of the Petterson scale. The results were statistically compared. We found a significant correlation between pain intensity and clinical pathology as well as between pain intensity and radiographic joint damage for both knees and for the right ankle. The number of painful joints correlated well with the number of clinically/radiographically affected joints. The more pronounced the objective damage to joints, the more frequently patients claimed to have constant pain, depressive episodes and a dependency on pain‐relieving medication. The more pronounced the objectively assessed damage to the knee and ankle joint, the higher the likelihood that the patient suffers from severe joint pain and reduction of activity. Treatment of painful symptoms from arthropathies is often insufficient. Scores and questionnaires may help to define the haemophiliacs pain status more clearly, thereby offering a possibility of assessment and long‐term observation.
In vivo recovery and safety of human factor VIII product AAFACT® in patients with haemophilia A
Authors: Vossebeld P. J. M. , Tissing M. H. , Van Den Berg H. M. , Leebeek F. W. G. , De Goede‐Bolder A. , NovÁkovÁ I. R. O. , Gerrits W. B. J. , Peters M. , Koopman M. M. W. , Faber A. , Hiemstra H. , Grob P. , Strengers P. F. W.
Published: March 2003

Summary.  AAFACT®, a monoclonal purified, solvent/detergent treated human plasma‐derived coagulation factor VIII concentrate obtained from plasma of voluntary, non‐remunerated blood donors, is manufactured and marketed in the Netherlands by Sanquin Plasma Products since 1995. In a postmarketing surveillance study, 70 previously treated haemophilia A patients were included (73% severe, 14% moderate and 13% mild haemophilia A). Most of these patients were followed during 4 years for the appearance of adverse events, possible transmissions of blood‐borne viruses and the occurrence of antibodies against FVIII. The efficacy of treatment was determined in each patient by the in vivo recovery of FVIII. During this study, only six adverse events, possibly related to the use of AAFACT®, were reported. None of these were indicated as serious. Transmissions of HIV, HAV, HBV and HCV in the seronegative patients have not been observed. In none of the patients, inhibitors to FVIII were detected. The in vivo recovery of FVIII during this study was not different from the in vivo recovery observed in eight patients during the preregistration study. There was a correlation of in vivo recovery with age and body weight. From these results, we conclude that the clinical usage of this human plasma‐derived FVIII product is efficient and safe.
The unusual distribution of the neuronal/lymphoid cell surface CD200 (OX2) glycoprotein is conserved in humans
Authors: Wright G. J. , Jones M. , Puklavec M. J. , Brown M. H. , Barclay A. N.
Published: March 2003

OX2 (CD200) is a type‐1 membrane glycoprotein that contains two immunoglobulin superfamily domains and which is expressed on a variety of lymphoid and non‐lymphoid cells in the rat. The recent characterization of a receptor for OX2 (OX2R) on myeloid cells, and the phenotype of an OX2‐deficient mouse, suggests that OX2 may regulate myeloid cell activity in anatomically diverse locations. Here we report the tissue distribution of the human homologue of the rat OX2 glycoprotein using a new monoclonal antibody (mAb), OX104, raised against recombinant human OX2. Human OX2 was expressed at the cell surface of thymocytes, B cells, T cells, neurons, kidney glomeruli, tonsil follicles, the syncytiotrophoblast and endothelial cells. This broad, but not ubiquitous, distribution pattern is very similar to that observed in rats, suggesting that OX2 may regulate myeloid cell activity in a variety of tissues in humans.
The standardized‐taper root canal preparation – Part 2. GT file selection and safe handpiece‐driven file use
Authors: Buchanan L. S.
Published: March 2003

Aim

To present guidelines on GT file selection, and safe operation.

It is not necessary to remove excessive dentine for effective root canal preparation. GT files allow safe, standardized preparation, and should be selected to fit the case in hand. Small Root canals should be prepared with 0.06 and 0.08 taper GT files, whilst Large Root canals should be prepared with 0.10 GT or 0.12 Accessory GT files. The greatest challenge is un‐learning habits acquired from traditional instrumentation methods. GT files should be used with light touch, and without up–down pumping motions. Spin speeds should be controlled below 300 r.p.m. for routine preparation. GT files are subject to fatigue and should be tracked to avoid overuse. It is recommended that GT files are discarded after the equivalent of five root canal preparations. For severe curvatures, GT files should be single‐case tools.

Key learning points

The standard GT file set comprises three instruments of 0.06, 0.08 and 0.10 taper. All are size 20 at the tip, and have a maximum diameter of 1 mm.

Accessory GT files have a standard taper 0.12, and maximum diameter of 1.5 mm. They are available in tip sizes 35, 50 and 70.

Large Roots are lower canines, upper anteriors, upper and lower single‐rooted premolars, palatal roots of upper molars and distal roots of lower molars. They should be prepared with 0.10 GT or 0.12 Accessory GT files.

Small Roots are lower incisors, multirooted premolars, buccal roots of upper molars and mesial roots of lower molars. They should be prepared with 0.06 or 0.08 GT files.

All GT files should be used with light force and at the correct spin speed.

GT files should be discarded after the equivalent of five root canal uses.
Relation between climate and vegetation along a Mediterranean‐Temperate boundary in central Italy
Authors: Blasi C. , Carranza M. L. , Filesi L. , Tilia A. , Acosta A.
Published: March 2003

The relationship between climate and vegetation was investigated along a Mediterranean‐Temperate boundary in central Italy. The study area is a transition zone between the Temperate (Eurosiberian) and Mediterranean regions and has an altitudinal range of almost 1750 m. Ordination and cluster analysis were used. The results did not show any sharp boundary but a climate‐vegetation mosaic ranging from upper mountain thermotype and lower hyperhumid ombrotype with Fagus sylvatica L. woodlands at higher altitudes, to meso‐Mediterranean thermotype and lower subhumid ombrotype with Mediterranean maquis and Quercus ilex L. woods on the coast. Six phytoclimatic groups are distinguished and described in terms of climatic parameters, vegetation types and morphological and chorological traits. These parameters indicate a change without sharp discontinuities between groups. The Mediterranean to Temperate transition in this Tyrrhenian sector is broad and includes most of the study area.
Deep‐rooted vegetation, Amazonian deforestation, and climate: results from a modelling study
Authors: Kleidon Axel , Heimann Martin
Published: March 2003

The depth of the root system controls the maximum amount of soil water that can be transpired by the vegetation into the atmosphere during dry periods. Water uptake from deep soil layers has been found to contribute significantly to the dry season transpiration at some sites in Amazonia and it has been estimated that large parts of the evergreen forests in Amazonia depend on deep roots to survive the dry season. Thus, the presence of deep roots might provide a significant source of atmospheric moisture during the dry season, and one which would be affected by deforestation. We investigate the role of deep‐rooted vegetation and its removal in the context of Amazonian deforestation using an atmospheric General Circulation Model (GCM). A distribution of deep roots is obtained by a numerical optimization approach. The simulated climate with the use of the calculated deep roots substantially improves the seasonal characteristics of the GCM. Three additional simulations are then conducted in order to isolate the effect of rooting depth reduction from other parameter changes associated with large‐scale deforestation. Most of the climatic effects occur during the dry season and are attributed to the reduction of rooting depth. Dry periods are found to last longer, being more intense with drier and warmer air, while the wet season remains fairly unchanged. The implications of these climatic effects for the re‐establishment of the natural evergreen forest are discussed.
On the stability of the high‐latitude climate‐vegetation system in a coupled atmosphere‐biosphere model
Authors: Levis Samuel , Foley Jonathan A. , Brovkin Victor , Pollard David
Published: March 2003

In order to investigate the hypothesis that the Earth's climate and vegetation patterns may have more than one basic state, we use the fully coupled GENESIS‐IBIS model. GENESIS is an atmospheric general circulation model. IBIS is a dynamic global vegetation model that integrates biophysical, physiological, and ecological processes. GENESIS and IBIS are coupled by way of a common land surface interface to allow for the full and transient interaction between changes in the vegetation structure and changes in the general circulation of the atmosphere. We examine two modern climate simulations of the coupled model initialized with two different initial conditions. In one case, we initialize the model vegetation cover with the modern observed distribution of vegetation. In the other case, we initialize the vegetation cover with evergreen boreal forests extending to the Arctic coast, replacing high‐latitude tundra. We interpret the coupled model's behaviour using a conceptual model for multistability and demonstrate that in both simulations the climate‐vegetation system converges to the same equilibrium state. In the present climate, feedbacks between land, ocean, sea ice, and the atmosphere do not result in the warming required to support an expanded boreal forest.
Concluding remarks: historical perspective and the future of island biogeography theory
Authors: Brown James H. , Lomolino Mark V.
Published: March 2003

MacArthur and Wilson’s equilibrium theory revolutionized the field of island biogeography and, to a large degree, ecology as well. The theory, which quickly became the ruling paradigm of island biogeography, has changed little over the past three decades. It has not kept pace with relevant theory and our growing appreciation for the complexity of nature, especially with empirical findings that species diversity on many islands: 1) is not in equilibrium; 2) is influenced by differences in speciation, colonization, and extinction among taxa; and 3) is influenced by differences among islands in characteristics other than area and isolation. The discipline of biogeography, itself, is in a state of disequilibrium. We may again be about to witness another paradigm shift, which will see the replacement of MacArthur and Wilson’s theory. Wherever this shift may take us, we are confident that the next generation of biogeographers will still look to islands for insights into the forces that shape biological diversity.
A comparison of structural characteristics between old‐growth and postfire second‐growth hemlock–hardwood forests in Adirondack Park, New York, U. S. A.
Authors: Ziegler Susy Svatek
Published: March 2003

1 This study compares the structural characteristics of 12 old‐growth and six postfire second‐growth hemlock–northern hardwood stands in north central Adirondack Park, New York, in order to test the null hypothesis that there are no differences in species composition, size structure, age structure and attributes such as dead wood and canopy gaps between old‐growth stands and this type of second‐growth forest.

2 The second‐growth forests of this study regenerated following widespread logging‐related fires in either 1903 or 1908; the old growth and second growth have similar environmental settings.

3 Estimates of stand ages, derived from an increment core of the oldest tree in each stand, range from 88 to 390 years.

4 Structural attributes are related to stand age (i.e. stage of development). In comparison with the second‐growth forests of this study, older stands are characterized as (a) a larger average diameter of canopy trees; (b) a greater basal area of trees; (c) a lower density of canopy trees and of all trees ≥ 10 cm d.b.h.; (d) a higher density of eastern hemlock (Tsuga canadensis(L.) Carrière) trees; (e) a higher density of large trees (≥ 50 cm d.b.h.); (f) larger canopy gaps; and (g) a greater volume of coarse woody debris (both logs ≥ 20 cm d.b.h. and snags ≥ 10 cm d.b.h.).

5 Despite differences between old growth and second growth, especially in species composition, it appears from observations of the 18 stands that second‐growth forests are developing some structural characteristics of old growth.

6 Structural attributes of the old‐growth forests are similar to characteristics of the same forest type in geographically distant areas in eastern USA.
Bird species numbers in an archipelago of reeds at Lake Velence, Hungary
Authors: Báldi András , Kisbenedek Tibor
Published: March 2003

1 Bird species numbers were studied on 109 reed islands at Lake Velence, Hungary, in the 1993 and 1994 breeding seasons. The aim was to describe and account for the abundance and distribution patterns of the bird species.

2 It was expected that an exponential model would fit the calculated species–area curves. However, for the 1993 data, both the power function (LogS ~ LogArea) and the exponential (S ~ LogArea) models did so, while the power function, exponential and linear (S ~ A) models fitted the curves for the 1994 data.

3 The results showed that the pattern was not random: a collection of small islands held more species than a few large islands with the same total area.

4 The relative species richness of small islands is a result of the preference of most common passerine bird species for the edges of reed islands. Most individuals were found in the first 5 m of the reedbed, and no edge avoidance was detected on a local spatial scale. Large, rarer species (e.g. Great White Egret), however, were found to be dependent on large reed islands.

5 Comparison of results with two other studies on bird communities of reed islands revealed that the type of landscape matrix (e.g. deep water, shallow water or agricultural lands) among reed patches significantly influences bird communities. Deep water was dominated by grebes and coot, shallow water by reed‐nesting passerines, and farmed areas by reed‐ and bush‐nesting passerines.
Endemism in the Australian flora
Authors: Crisp M. D. , Laffan S. , Linder H. P. , Monro A.
Published: March 2003

Aim

To detect centres of vascular plant endemism at a continental scale by analysis of specimen‐based distributional data and to relate any pattern to environmental factors and history.

Location

Australia.

Methods

Presence of 8468 seed plant species‐level taxa throughout continental Australia and Tasmania was mapped on a 1° grid to visualize the pattern of species richness. This sample comprises half the known flora. Three indices of endemism were calculated but we preferred one that is unrelated to species richness, so that these two concepts could be distinguished in practice. Centres of endemism were detected by simple mapping and by spatial autocorrelation analysis (SAC). Linear regression was used to examine the relationship of the patterns of species richness and endemism to latitude, topography and climate.

Results

Both species richness and endemism vary greatly across the continent but in most cases the same centres were high in both richness and endemism. Twelve distinct centres were identified. The major centres of both diversity and endemism are south‐west western Australia, the Border Ranges between New South Wales and Queensland, the Wet Tropics near Cairns, Tasmania and the Iron‐McIlwraith Range of eastern Cape York Peninsula. The last centre appears to be more significant than recognized by past authors. Whether this is a true Australian centre of endemism, or is largely an outlier of the flora of Papua New Guinea, is explored. Another centre, in the Adelaide–Kangaroo Island region, has been overlooked altogether by previous authors. Regression analysis did not find a simple climatic explanation of the observed patterns. There was a suggestion that topographic variation within the 1° cells may be positively correlated with endemism, which is consistent with mountainous regions functioning as refugia. One clear result is that all the major centres of endemism are near‐coastal. A likely explanation is that Pleistocene expansions of the central desert have been a powerful limitation on the viability of refugia for narrowly endemic species. All the centres of endemism lie outside the estimated limits of the expanded arid zone at the last glacial maximum (18,000 yr BP). In particular, the ‘Central Australian Mountain Ranges centre of plant diversity and endemism’ ofBoden & Given (1995)is detected as a strong centre of species richness, but not at all as a centre of endemism. This is despite good sampling of this region.

Main conclusions

Endemism can be distinguished from species richness by using an appropriate index and mapping of such indices can detect centres of endemism. This study demonstrates the value of specimen based distributional data, such as is held in state herbaria and museums.
High incidence of adverse reactions to egg challenge on first known exposure in young atopic dermatitis children: predictive value of skin prick test and radioallergosorbent test to egg proteins
Authors: Monti G. , Muratore M. C. , Peltran A. , Bonfante G. , Silvestro L. , Oggero R. , Mussa G. C.
Published: March 2003

Background Egg skin prick test (SPT) and/or radioallergosorbent test (RAST) positivity has been described in infants and children with a food allergy, or in infants at high risk of atopy who have never eaten eggs. Clinical reactions are also observed when some of these children or infants eat eggs for the first time.

Objective and method A prospective study was made of 107 atopic dermatitis (AD) children (66 boys, 41 girls) aged 1–19 months (median 5 months) who had never ingested egg, to compare the outcome of a first oral egg challenge and the results of albumen and yolk SPTs and RASTs.

Results The egg challenge (conducted at age 12–24 months: mean 16 months, median 15 months) was positive in 72/107 children (67.3%). The reactions were immediate or early (first 6 h) in 56/72 (77.8%). The most severe (all within the first 6 h) were one case of anaphylactic shock (1.4%), three cases of laryngeal oedema (4.1%) and one serious attack of asthma (1.4%). The skin weal diameter at and above which reactions always occurred was 5 mm for both albumen and yolk. They were, however, also observed in the complete absence of a weal. The outcome of the challenge was always positive when the specific IgEs (sIgE) for albumen and yolk were > 99 KU/L and ≥ 17.5 KU/L, respectively. Here, too, reactions were noted even when sIgE levels were < 0.35 KU/L.

Conclusion AD children who have never eaten eggs may be sensitized and display reactions at the first ingestion. The percentage of reactions in this series was by no means negligible. These findings were observed in children with mild as well as moderate–severe AD when first examined. SPT for albumen and yolk diameter ≥ 5 mm, and sIgE for albumen > 99 KU/L and for yolk ≥ 17.5 KU/L were 100% specific in predicting the outcome of the challenge. It may thus be concluded that children with AD whose SPT and/or RAST for albumen and/or yolk are equal to or higher than these cut‐off values should not be subjected to the oral challenge when consideration is given to the introduction of egg in their diet. Even when these cut‐offs are not reached, however, clinical reactions to the challenge cannot be ruled out a priori, and it should be preferably performed in a protected environment, such as a hospital.
Allergy after ingestion or inhalation of cereals involves similar allergens in different ages
Authors: Armentia A. , Rodríguez R. , Callejo A. , Martín‐Esteban M. , Martín‐Santos J.‐M. , Salcedo G. , Pascual C. , Sánchez‐Monge R. , Pardo M.
Published: March 2003

Background Cereals are among the major foods that account for food hypersensitivity reactions. Salt‐soluble proteins appear to be the most important allergens contributing to the asthmatic response. In contrast, very limited information is available regarding cereal allergens responsible for allergic reactions after ingestion of cereal proteins.

Objective The aim of this study was to evaluate the allergenic reactivity of ingested and inhaled cereal allergens in different ages, in order to investigate if the response to different allergens would depend on the sensitization route.

Methods We included 66 patients in three groups. Group 1: 40 children aged 3 to 6 months who suffered from diarrhoea, vomiting, eczema or weight loss after the introduction of cereal formula in their diet and in which a possibility of coeliac disease was discarded. Group 2: 18 adults with food allergy due to cereals tested by prick tests, specific IgE and food challenge. Group 3: eight patients previously diagnosed as having baker's asthma. Sera pool samples were collected from each group of patients and IgE immunoblotting was performed.

Results We found an important sensitization to cereal in the 40 children. The most important allergens were wheat followed by barley and rye. Among the adults with cereal allergy, sensitization to other allergens was common, especially to Lolium perenne (rye grass) pollen. Immunoblotting showed similar allergenic detection in the three groups.

Conclusion Clinically significant reactivity to cereal may be observed in early life. Inhalation and ingestion routes causing cereal allergy seem to involve similar allergens. The diet control was more effective in children. The possibility of cereal allergy after the introduction of cereal formula during the lactation period should not be underestimated.
Prevalence and severity of allergic rhinitis in house dust mite‐allergic patients with bronchial asthma or atopic dermatitis
Authors: Terreehorst I. , Oosting A. J. , Tempels‐Pavlica Z. , De Monchy J. G. R. , Bruijnzeel‐Koomen C. A. F. M. , Hak E. , Van Wijk R. Gerth
Published: March 2003

Background Allergic rhinitis, asthma and atopic dermatitis are closely associated. Although population‐based studies report a high prevalence of rhinitis among asthma patients, less is known of the association between rhinitis and atopic dermatitis and the severity of concomitant rhinitis.

Objectives We aimed to determine the prevalence and severity of allergic rhinitis among asthmatics and patients with atopic dermatitis and assessed whether age and comorbidity influence the severity of rhinitis signs and symptoms.

Methods Three hundred and twenty‐five patients recruited for a multicentre trial to study the effect of encasings of mattresses, pillows and duvets on signs and symptoms of allergic rhinitis and/or asthma and/or atopic dermatitis recorded visual analogue scores (VAS) and daily symptom scores and underwent nasal challenge tests with house dust mite (HDM).

Results Based on history and clinical symptoms 92% of the 164 asthmatic patients and 85% of the 86 patients with atopic dermatitis could be diagnosed as having rhinitis. Inclusion of a positive provocation to HDM did not result in a substantial lower prevalence of rhinitis. Subjects reported moderate symptoms, with mean rhinitis VAS scores ranging from 40.0 to 55.0. Presence of atopic dermatitis was associated with lower rhinitis VAS and symptoms scores, whereas in multivariate analysis the presence of asthma was positively associated with nasal responsiveness to HDM.

Conclusion The prevalence of nasal symptoms in patients with bronchial asthma or atopic dermatitis and sensitized to house dust mites is high. Although the majority of patients experience mild to moderate symptoms, the presence of nasal disease needs to be examined in all patients with atopic disorders.
What can patients do to improve health care?
Authors: Wensing Michel , Grol Richard
Published: March 2003

ObjectiveTo give an overview of the value of different interventions for increasing the role of individual patients in improving the quality of care provision.

Search strategyMedline searches and manual searches in medical journals covering the period from 1980 until June 1997.

Inclusion criteriaStudies reporting descriptions and evaluations of seven types of interventions that aim to help integrate the needs and preferences of individual patients into health care provision.

Data extractionThe following information was extracted: assumptions underlying the interventions; resources needed for development and implementation; and acceptability to clinicians.

Main resultsSeveral interventions for increasing patients' roles in health care could be successful in clinical practice, such as feeding forward patient data to clinicians, interactive patient education and feedback to health care providers about patients' evaluations of care. The available research focuses on feedback methods. Insights into the benefits and limitations of the use of the different interventions for improving care are limited.

ConclusionThe active role that patients' views play in the contact with a care provider is often neglected. Promising interventions for the empowerment of individual patients require further development and evaluation.