Understanding and promoting adoption of conservation practices by rural landholders

Research on the adoption of rural innovations is reviewed and interpreted through a cross-disciplinary lens to provide practical guidance for research, extension and policy relating to conservation practices. Adoption of innovations by landholders is presented as a dynamic learning process. Adoption depends on a range of personal, social, cultural and economic factors, as well as on characteristics of the innovation itself. Adoption occurs when the landholder perceives that the innovation in question will enhance the achievement of their personal goals. A range of goals is identifiable among landholders, including economic, social and environmental goals. Innovations are more likely to be adopted when they have a high ‘relative advantage’ (perceived superiority to the idea or practice that it supersedes), and when they are readily trialable (easy to test and learn about before adoption). Non-adoption or low adoption of a number of conservation practices is readily explicable in terms of their failure to provide a relative advantage (particularly in economic terms) or a range of difficulties that landholders may have in trialing them.

Protein–Surface Interactions: An Energy-Based Mathematical Model

This article describes an energy-based approach to protein adsorption, focusing on the energies involved in the interactions between a protein and a surface. Mathematical modeling and simulation based on this approach allow an improved understanding of the conditions that favor or prevent adsorption of a protein onto a surface and that can play a significant role in the design of material surfaces that interact with biological tissues according to specific needs. Biocompatibility with respect to fluids in motion, such as blood, is the main foreseeable application of our work. The considered energies are the van der Waals energy, the electrostatic energy, and the hydrophobic or hydrophilic energy. Moreover, the motion of the medium in which particles are immersed is also taken into account, considering the drag effect of the motion of the fluid on the particle, leading to a kinetic contribution to the total energy. It is shown that the adsorption behavior is not mainly determined by the van der Waals energy and by the double layer energy, but that a significant role is also played by the hydrophobic or hydrophilic energy. These results support the findings of experimental studies.

Identification of a mutation in synapsin I, a synaptic vesicle protein, in a family with epilepsy

A four generation family is described in which some men of normal intelligence have epilepsy and others have various combinations of epilepsy, learning difficulties, macrocephaly, and aggressive behaviour. As the phenotype in this family is distinct from other X linked recessive disorders linkage studies were carried out. Linkage analysis was done using X chromosome microsatellite polymorphisms to define the interval containing the causative gene. Genes from within the region were considered possible candidates and one of these, SYN1, was screened for mutations by direct DNA sequencing of amplified products. Microsatellite analysis showed that the region between MAOB (Xp11.3) and DXS1275 (Xq12) segregated with the disease. Two point linkage analysis demonstrated linkage with DXS1039, lod score 4.06 at theta = 0, and DXS991, 3.63 at theta = 0. Candidate gene analysis led to identification of a nonsense mutation in the gene encoding synapsin I that was present in all affected family members and female carriers and was not present in 287 control chromosomes. Synapsin I is a synaptic vesicle associated protein involved in the regulation of synaptogenesis and neurotransmitter release. The SYN1 nonsense mutation that was identified is the likely cause of the phenotype in this family.

Micro and nano-structured surfaces

The study of cell reaction to micro and nanotopography is dependent on the method of manufacture available. Several methods of manufacture have been developed: polymer demixing, embossing and photolithography. Surfaces obtained with these different techniques, having micro and/or nanodomains, have been studied toward the same type of cells, i.e. human endothelial cells (HGTFN) and mouse fibroblasts (3T3). Polymer demixing of polystyrene (PS) and poly(4-bromostyrene) (PBrS) producing nanometrically islands of 18, 45 and 100 nm height, polycarbonate (PC) and polycaprolactone (PCL) grooved with grooves 450 nm wide and 190 high, the natural polysaccharide hyaluronic acid (Hyal) and its sulfated derivative (HyalS) photoimmobilized on silanized glass as grooves 250 nm high and 100, 50, 25 or 10 microm wide have been obtained. The morphology and polarization of the cells has been studied by optical microscopy and scanning electron microscopy. Cells respond in different way to the topography of the materials, but the surface chemistry is dominant in inducing different cell behavior.

Successful umbilical cord blood stem cell transplantation for chronic granulomatous disease

Chronic granulomatous disease (CGD) causes growth failure, inflammatory lung damage and often early death. Prophylactic cotrimoxazole improves medium-term survival, but cannot prevent inflammatory sequelae. We report the first patient with CGD who underwent successful HLA identical sibling umbilical cord stem cell transplantation (UCSCT) after myeloablative conditioning. The patient presented with colitis, confirmed as CGD at 2 years of age. Following BU16/CY200 conditioning, he had UCSCT from his unaffected HLA identical sister. A year post-transplant, his colitis had resolved clinically and on radioisotope scan growth has improved. Neutrophil oxidative burst was 92% normal with full donor lymphocyte reconstitution.

Prevalence of R117H mutation in the cationic trypsinogen gene in patients with hereditary pancreatitis

Background

The R117H mutation of the cationic trypsinogen (CT) gene (G to A mutation in exon 3), located on chromosome 7q35, is one of the known mutations that is linked to hereditary pancreatitis (HP) and is thought to alter a trypsin recognition site responsible for the breakdown of inappropriately activated trypsinogen so resulting in pancreatitis. The aim of this study was to determine the prevalence of this mutation in patients with HP and to correlate presence of the mutation with disease characteristics.

Methods

Polymerase chain reaction amplification of the third exon of the CT gene was performed on blood DNA. This was digested by the restriction endonuclease Afl III and fragments were sized by agarose gel electrophoresis. Haplotype analysis was carried out using three short tandem repeat markers in the region of the CT gene.

Results

Seven discrete families with HP (three to seven generations) were identified (22 affected individuals). The mutation was present in individuals from three of the seven families. It was absent in all affected individuals from the other four families. A higher proportion of patients requiring pancreatic surgery was seen in families expressing this mutation (eight of 14 versus one of eight, P = 0·016). Mean(s.d.) age of onset was similar in both groups (7·9(5·8) versus 6·3(10·1) years, P = 0·13). In the affected families, the same high-risk haplotype was present in two families, suggesting a common ancestor. The third family carried a unique haplotype.

Conclusion

A single G to A mutation in the third exon of the CT gene was found in three families with HP originating from this region and appears to be associated with more severe disease. Further work is being undertaken to analyse the CT gene more fully in families in which this common first mutation was not identified.

CAMPATH-1M T-cell depleted BMT for SCID: long-term follow-up of 19 children treated 1987-98 in a single center

BACKGROUND

SCID can be cured by BMT. Depletion of mature T cells from BM has enabled HLA non-identical stem-cell transplantation. We report the outcome of 30 patients treated with 37 T-cell depleted BMT procedures using CAMPATH-1M in vitro between 1987-98 in a single center.

METHODS

Immune reconstitution and quality-of-life were assessed in 19 longterm survivors. All but two received pre-transplant conditioning. T- and B-cell chimerism, numbers and function were analyzed during a median follow-up of 5.3 years (range 1.33-12).

RESULTS

The overall engraftment rate was 59%, six children required repeated BMT and the survival rate was 63%. All have donor T cells, 58% normal T-cell numbers and 74% normal T-cell function. Of 17 evaluated, 16 patients (94%) have normal IgM and IgG levels, and production of specific Abs to protein Ags, but only 5/16 (31%) have a good response to pneumococcal polysaccharide. Early and late post-BMT complications were rare and there were no delayed deaths. Only one child continues on long-term i.v. Ig 4-years post-BMT. Eleven children died (37%).

DISCUSSION

CAMPATH-1M T-cell depleted BMT for SCID resulted in 63% survival. Deaths of 11 children were mainly due to pre-existing infections. Seventeen of 19 long-term survivors have normal immune function and good quality-of-life.

Absence of a genetic association between IL-1RN and IL-1B gene polymorphisms in ulcerative colitis and Crohn disease in multiple populations from northeast England

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic inflammation of the gastrointestinal tract of unknown aetiology, phenotypically categorized into ulcerative colitis (UC) and Crohn disease (CD). Genetic factors are of considerable importance in both. The genetic relationship between IBD and the interleukin-1 receptor antagonist and interleukin-1beta genes (IL-1RN, and IL-1B, respectively) has been extensively studied. However, the quality and outcome of the genetic association studies, in particular the association with IL-1RN*2, have been variable and these associations remain controversial. The aim of the present study was to re-investigate these two candidate genes in a large series of IBD patients from a genetically homogeneous population with low levels of population admixture, and provide a definitive answer to this question.

METHODS

A total of 529 northern European Caucasoid patients with IBD (347 UC, 182 CD) and 289 racially and geographically matched healthy controls were studied. The IL-1RN and IL-1B genotypes, allele frequencies and most probable haplotypes were determined by standard PCR protocols.

RESULTS

There were no significant differences in the distributions of the IL-1RN and IL-1B genotypes, allele frequencies or haplotypes in either patient series compared to healthy controls or between clinical subsets. Genotype distribution and frequency data for allele 2 (IL-1RN*2) in particular showed no significant differences across all patient groups for all three series.

CONCLUSION

The findings of this study lead us to reject the IL-1RN*2 association with IBD.

Donor-acquired small cell lung cancer following pulmonary transplantation

We describe a case of donor-acquired small cell lung cancer after pulmonary transplantation for cystic fibrosis. The recipient was an ex-smoker with minimal smoking history and had been abstinent for 20 years. At the time of death, the donor chest radiographic finding was normal. The recipient had multiple posttransplant bronchoscopies and a normal CT scan result at 4 months after transplantation. The recipient presented 13 months after transplantation with metastatic disease. He did not respond to chemotherapy and died shortly thereafter. Molecular genetic techniques revealed that the primary tumor and metastases were different to recipient tissues, confirming the donor origin.

Mutation in the gene encoding ferritin light polypeptide causes dominant adult-onset basal ganglia disease

We describe here a previously unknown, dominantly inherited, late-onset basal ganglia disease, variably presenting with extrapyramidal features similar to those of Huntington's disease (HD) or parkinsonism. We mapped the disorder, by linkage analysis, to 19q13.3, which contains the gene for ferritin light polypeptide (FTL). We found an adenine insertion at position 460-461 that is predicted to alter carboxy-terminal residues of the gene product. Brain histochemistry disclosed abnormal aggregates of ferritin and iron. Low serum ferritin levels also characterized patients. Ferritin, the main iron storage protein, is composed of 24 subunits of two types (heavy, H and light, L) which form a soluble, hollow sphere. Brain iron deposition increases normally with age, especially in the basal ganglia, and is a suspected causative factor in several neurodegenerative diseases in which it correlates with visible pathology, possibly by its involvement in toxic free-radical reactions. We found the same mutation in five apparently unrelated subjects with similar extrapyramidal symptoms. An abnormality in ferritin strongly indicates a primary function for iron in the pathogenesis of this new disease, for which we propose the name 'neuroferritinopathy'.

Tissue engineering: the biophysical background

Tissue engineering is the construction, repair or replacement of damaged or missing tissue in humans and other animals. This engineering may take place within the animal body or as tissue constructs to be made in a bioreactor for later grafting into the animal. The minimal set of materials for this are the appropriate types of cell. Usually, however, non-living substrata are used as well. These substrata may be nothing more than materials that bulk up any voids in the damaged tissue and provide the mechanical strength that has been lost when the tissue is damaged or removed. They may serve a similar pair of functions in the bioreactor. They can do much more in terms of pattern formation. The orientations and morphology of the cells, the arrangement of intercellular material as it is laid down and the relationships between different cell types in the repairing or construct tissue are all of importance, for these should resemble the correct normal tissue as closely as possible. Most of these requirements are ones involving pattern formation. This review discusses the various ways in which tissue pattern can be engineered chiefly from a biophysical standpoint. Unpatterned cells are effectively not tissue. This engineering includes the use of topography on the substrata, chemical patterning of adhesive and other cues for the cells, mechanical force application to cause cell orientation and appropriate synthetic responses and electrical fields. The review also discusses the methods used to impart the appropriate cues to and through the materials which are often biodegradable polymers. The article gives particular attention to regions of research and practice where the involvement of the physicist or biophysicist is of importance.

Nantotechniques and approaches in biotechnology

Nanotechnology has enabled the development of an amazing variety of methods for fabricating nanotopography and nanopatterned chemistry in recent years. Some of these techniques are directed towards producing single component particles, as well as multi-component assembly or self-assembly. Other methods are aimed at nanofeaturing and patterning surfaces that have a specific chemistry or topography. This article concentrates mainly on surface-directed nanobiotechnologies because they are nearer to commercial realisation, such as use in tissue engineering, control of biofouling and cell culture, than those directed at producing nanoparticles.

Medical and surgical treatment of parapneumonic effusions : an evidence-based guideline

OBJECTIVE

A panel was convened by the Health and Science Policy Committee of the American College of Chest Physicians to develop a clinical practice guideline on the medical and surgical treatment of parapneumonic effusions (PPE) using evidence-based methods.

OPTIONS AND OUTCOMES CONSIDERED

Based on consensus of clinical opinion, the expert panel developed an annotated table for evaluating the risk for poor outcome in patients with PPE. Estimates of the risk for poor outcome were based on the clinical judgment that, without adequate drainage of the pleural space, the patient with PPE would be likely to have any or all of the following: prolonged hospitalization, prolonged evidence of systemic toxicity, increased morbidity from any drainage procedure, increased risk for residual ventilatory impairment, increased risk for local spread of the inflammatory reaction, and increased mortality. Three variables, pleural space anatomy, pleural fluid bacteriology, and pleural fluid chemistry, were used in this annotated table to categorize patients into four separate risk levels for poor outcome: categories 1 (very low risk), 2 (low risk), 3 (moderate risk), and 4 (high risk). The panel's consensus opinion supported drainage for patients with moderate (category 3) or high (category 4) risk for a poor outcome, but not for patients with very low (category 1) or low (category 2) risk for a poor outcome. The medical literature was reviewed to evaluate the effectiveness of medical and surgical management approaches for patients with PPE at moderate or high risk for poor outcome. The panel grouped PPE management approaches into six categories: no drainage performed, therapeutic thoracentesis, tube thoracostomy, fibrinolytics, video-assisted thoracoscopic surgery (VATS), and surgery (including thoracotoiny with or without decortication and rib resection). The fibrinolytic approach required tube thoracostomy for administration of drug, and VATS included post-procedure tube thoracostomy. Surgery may have included concomitant lung resection and always included postoperative tube thoracostomy. All management approaches included appropriate treatment of the underlying pneumonia, including systemic antibiotics. Criteria for including articles in the panel review were adequate data provided for >/=20 adult patients with PPE to allow evaluation of at least one relevant outcome (death or need for a second intervention to manage the PPE); reasonable assurance provided that drainage was clinically appropriate (patients receiving drainage were either category 3 or category 4) and drainage procedure was adequately described; and original data were presented. The strength of panel recommendations on management of PPE was based on the following approach: level A, randomized, controlled trials with consistent results or individual randomized, controlled trial with narrow confidence interval (CI); level B, controlled cohort and case control series; level C, historically controlled series and case series; and level D, expert opinion without explicit critical appraisal or based on physiology, bench research, or "first principles."

EVIDENCE

The literature review revealed 24 articles eligible for full review by the panel, 19 of which dealt with the primary management approach to PPE and 5 with a rescue approach after a previous approach had failed. Of the 19 involving the primary management approach to PPE, there were 3 randomized, controlled trials, 2 historically controlled series, and 14 case series. The number of patients included in the randomized controlled trials was small; methodologic weaknesses were found in the 19 articles describing the results of primary management approaches to PPE. The proportion and 95% CI of patients suffering each of the two relevant outcomes (death and need for a second intervention to manage the PPE) were calculated for the pooled data for each management approach from the 19 articles on the primary management approach. (ABST