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At least 19 recordsLinked to original sources
PubMed2000

Conservative interventions for treating distal radial fractures in adults.

BACKGROUND: Fracture of the distal radius is a common clinical problem particularly in elderly white women with osteoporosis, in whom the lifetime risk of this injury has been estimated as 15 per cent. OBJECTIVES: To determine the most appropriate conservative treatment for fractures (such as Colles') of the distal radius in adults. SEARCH STRATEGY: We searched the Cochrane Musculoskeletal Injuries Group trials register, Medline and reference lists of trials. Date of the most recent search: April 1998. SELECTION CRITERIA: Randomised or quasi-randomised clinical trials involving skeletally mature patients with a fracture of the distal radius, which compared commonly applied conservative interventions for fracture fixation. These included the application of an external support (plaster cast or brace) and fracture manipulation. DATA COLLECTION AND ANALYSIS: All trials, judged as fitting the selection criteria by both reviewers, were independently assessed by both reviewers for methodological quality. Data were extracted for anatomical, functional and clinical, including complications, outcomes. The trials were grouped into categories relating to cast position, extent and duration of immobilisation, use of braces, cast material and fracture manipulation. Although quantitative data from some trials are presented, the lack of good quality trials and trial heterogeneity inhibited pooling of results. MAIN RESULTS: Over 50 randomised trials comparing treatment options for distal radial fractures were identified. Twenty nine trials of these, involving a total of 3199 mainly female and older patients, met the inclusion criteria for this review. Comprehensive details of the individual trials are provided in tabular form, and their results, grouped as indicated above, have been presented in text and analyses tables. The poor quality and heterogeneity in terms of patient characteristics, interventions compared and outcome measurement, of the included trials meant that no meta-analyses were undertaken. REVIEWER'S CONCLUSIONS: There is insufficient evidence from randomised trials to determine which methods of conservative treatment are the most appropriate for the more common types of distal radial fractures in adults. Therefore, at present, practitioners applying conservative management should use an accepted technique with which they are familiar, and which is cost-effective from the perspective of their provider unit. Whilst tempting, any call for further research to clarify the most appropriate conservative treatment for this common fracture must be resisted for now. Instead it is important to reflect on the issues raised in this review, to ascertain patient preferences, prioritise researchable questions and undertake a systematic programme of research after agreeing a core data set for classification of fractures and outcomes.

Adult↗
PubMed2003

Global variation in terrestrial conservation costs, conservation benefits, and unmet conservation needs.

Our ability to identify cost-efficient priorities for conserving biological diversity is limited by the scarcity of data on conservation costs, particularly at fine scales. Here we address this issue using data for 139 terrestrial programs worldwide. We find that the annual costs of effective field-based conservation vary enormously, across seven orders of magnitude, from <$0.1 to >$1,000,000 per km(2). This variation can be closely predicted from positive associations between costs per unit area and an array of indices of local development. Corresponding measures of conservation benefit are limited but show opposing global trends, being higher in less developed parts of the world. The benefit-to-cost ratio of conservation is thus far greater in less developed regions, yet these are where the shortfall in current conservation spending is most marked. Substantially increased investment in tropical conservation is therefore urgently required if opportunities for cost-effective action are not to be missed.

Conservation of Natural Resources↗
PubMedDate not supplied

Optimum allocation of conservation funds and choice of conservation programs for a set of African cattle breeds.

Although funds for livestock conservation are limited there is little known about the optimal allocation of conservation funds. A new algorithm was used to allocate Mio US dollar 1, 2, 3, 5 or unlimited funds, discounted over 50 years, on 23 African cattle breeds conserved with four different possible conservation programs. Additionally, Mio US dollar 1 was preferably allocated to breeds with special traits. The conceptional in situ conservation programs strongly involve breeders and give them part of the responsibility for the conservation of the breed. Therefore, the pure in situ conservation was more efficient than cryoconservation or combined in situ and cryoconservation. The average annual discounted conservation cost for a breed can be as low as US dollar 1000 to US dollar 4400 depending on the design of the conservation program and the economic situation of the country of conservation. The choice of the breeds and the optimal conservation program and the amount of money allocated to each breed depend on many factors such as the amount of funds available, the conservation potential of each breed, the effects of the conservation program as well as its cost. With Mio US dollar 1, 64% of the present diversity could be maintained over 50 years, which is 13% more than would be maintained if no conservation measures were implemented. Special traits could be conserved with a rather small amount of the total funds. Diversity can not be conserved completely, not even with unlimited funds. A maximum of 92% of the present diversity could be conserved with Mio US dollar 10, leaving 8% of the diversity to unpredictable happenings. The suggested algorithm proved to be useful for optimal allocation of conservation funds. It allocated the funds optimally among breeds by identifying the most suited conservation program for each breed, also accounting for differences in currency exchange rates between the different countries.

Africa↗
PubMed2002

Conserving biodiversity that matters: practitioners' perspectives on brownfield development and urban nature conservation in London.

Policies designed to conserve sites of nature conservation importance are an important aspect of city planning in the UK. London has led the way in putting in place a spatial hierarchy of sites of nature conservation importance designed to protect wildlife habitats from development. Some wasteland habitats associated with derelict and vacant land receive protection in this way but development pressure on these so-called 'brownfield sites' is high and is likely to continue. This paper examines how conservation professionals in the private, public and voluntary sectors are responding to the threats of biodiversity loss and opportunities for habitat creation posed by re-development of brownfield sites. The study draws on in-depth interviews conducted with conservation professionals and the practices employed by ecological advisers employed by developers seeking to re-develop wasteland sites. It finds that practitioners are negotiating their role in the re-development process in different ways. Key issues relate to the role of ecological science in codifying wasteland habitats, uncertainties about how best to evaluate the conservation importance of such sites and the strategies and tactics employed by different practitioners as they seek to mobilise a range of knowledges and practices to secure ecologically sensitive proposals. Scientific knowledge about wasteland habitats has not stabilised in ways that can consistently inform conservation policy and practice. As a result biodiversity issues of wasteland sites are often discounted in the re-development process. Investment in studies of the basic ecology of urban wastelands could provide a firmer scientific foundation on which conservation policies could build. At the same time, many conservation professionals involved in urban re-development are struggling to promote a pro-active approach to secure environmentally sensitive development. The knowledge and co-operation networks being mobilised to support this approach are fluid and unstable, and favourable development outcomes as yet are few. Formalising these networks to achieve more effective engagements with developers and the construction industry could consolidate ecological practices designed to conserve and re-create the biodiversity of wasteland habitats.

Animals↗
PubMed1996

Conservation of amino acids in multiple alignments: aspartic acid has unexpected conservation.

Analysis of the relationship between surface accessibility and amino acid conservation in multiple sequence alignments of homologous proteins confirms expected trends for hydrophobic amino acids, but reveals an unexpected difference between the conservation of Asp, Glu and Gln. Even when not in an active site, Asp is more highly conserved than Glu. There is a clear preference for conserved and buried Asp to be present in coil, but there is no tendency for Asp to conserve phi/psi in the ++ region of the Ramachandran map. Glu does not show any preference to be conserved in a particular secondary structure. Analysis of recently derived substitution matrices (e.g. BLOSUM) confirms that Glu tends to substitute more frequently with other amino acids than does Asp. Analysis of relative accessibility versus relative conservation for individual amino acid positions in alignments shows a negative correlation for all amino acid types. With the exception of Arg, Lys, Gly, Glu, Asp and Tyr, a relative conservation of > 2 suggests the amino acid will have a relative accessibility of < 50%. Observation of conserved Cys, Gly or Asp in a reliable multiple alignment suggests a position important for the structure of the protein. Furthermore, the Asp is likely to be involved in polar interactions through its side chain oxygen atoms. In contrast, Gln is the least conserved amino acid overall.

Amino Acid Sequence↗
PubMed2003

The conserved and non-conserved regions of Rpb4 are involved in multiple phenotypes in Saccharomyces cerevisiae.

Rpb4, the fourth largest subunit of RNA polymerase II in Saccharomyces cerevisiae, is required for many phenotypes, including growth at high and low temperatures, sporulation, pseudohyphal growth, activated transcription of a subset of genes, and efficient carbon and energy metabolism. We have used deletion analysis to delineate the domains of the protein involved in these multiple phenotypes. The scRpb4 protein is conserved at the N and C termini but possesses certain non-conserved regions in the central portion. Our deletion analysis and molecular modeling results show that the N- and C-terminal conserved regions of Rpb4 are involved in interaction with Rpb7, the Rpb4 interacting partner in the RNA polymerase II. We further show that the conserved N terminus is required for efficient activated transcription from the INO1 promoter but not the GAL10- or the HSE-containing promoters. The N terminus is not required for any of the stress responses tested: growth at high temperatures, sporulation, and pseudohyphal growth. The conserved C-terminal 23 amino acids are not required for the role of Rpb4 in the pseudohyphal growth phenotype but might play a role in other stress responses and activated transcription. From the deletion analysis of the non-conserved regions, we report that they influence phenotypes involving both the N and C termini (interaction with Rpb7 and transcription from the INO1 promoter) but not any of the stress-responsive phenotypes tested suggesting that they might be involved in maintaining the two conserved domains in an appropriate conformation for interaction with Rpb7 and other proteins. Taken together, our results allow us to assign phenotype-specific roles for the different conserved and non-conserved regions of Rpb4.

Amino Acid Sequence↗
PubMed2006

Conservation as virtue: a scientific and social process for conservation ethics.

Most scientists take ethical arguments for conservation as given and focus on scientific or economic questions. Although nature conservation is often considered a just cause, it is given little further consideration. A lack of attention to ethical theory raises serious concerns for how conservation scientists conceive and practice ethics. I contrast two common ways scientists approach ethics, as demonstrated in the writings of Stephen Jay Gould and E. O. Wilson. Gould casts severe doubt as to whether any ethics are possible from science, whereas Wilson proposes science as the only path to ethics. I argue these two methods ultimately limit popular support for conservation and offer Alasdair MacIntyre's "virtue ethics" as an alternative. Unlike Gould and Wilson, MacIntyre provides an ethical theory that reconciles scientific inquiry and social traditions. Recent studies of the Civil Rights Movement in the United States affirm MacIntyre's claims and provide important insights for conservation today. These accounts argue that social solidarity and political success against segregation were possible only as rooted in the particular language, logic, and practices of a robust cultural tradition. If correct, conservation science should attend to several questions. On what basis can conservation achieve widespread cultural legitimacy? What are the particular social currencies for a conservation ethic? What role does science play in such a scheme? MacIntyre's careful positioning of scientific and social traditions provides a hopeful ethical direction for conservation.

Bioethical Issues↗
PubMed2000

Conservative versus operative treatment for extracapsular hip fractures.

BACKGROUND: Until operative treatment involving the use of various implants was introduced in the 1950s, hip fractures were managed using conservative methods based on traction and bed rest. OBJECTIVES: To compare conservative with operative treatment for extracapsular fractures of the proximal femur (hip) in adults. SEARCH STRATEGY: We searched the Cochrane Musculoskeletal Injuries Group trials register and bibliographies of published papers, and contacted trialists. Date of the most recent search: August 1999. SELECTION CRITERIA: Randomised and quasi-randomised trials comparing these two treatment methods in adults with hip fracture. Outcomes sought fell into four categories: a) fracture fixation complications, b) post-operative or clinical complications, c) final outcome measures including mortality and d) anatomical restoration. DATA COLLECTION AND ANALYSIS: Both reviewers independently assessed trial quality, by use of an eleven item scale, and extracted data. Additional information was sought from trialists. Comparable groups of trials were subgrouped by implant type (fixed nail plate or sliding hip screw) and where appropriate, data were pooled using the fixed effects model. MAIN RESULTS: The four randomised trials identified involved only 402 elderly patients. These tested a variety of surgical techniques and implant devices and only one trial involving 106 patients can be considered to test current practice. In this trial, no differences were found in medical complications, mortality and long-term pain. However, operative treatment was more likely to result in the fracture healing without leg shortening, a shorter hospital stay and a statistically non-significant increase in the return of patients back to their original residence. REVIEWER'S CONCLUSIONS: The limited available evidence from randomised trials does not suggest major differences in outcome between conservative and operative management programmes for extracapsular femoral fractures, but operative treatment appears to be associated with a reduced length of hospital stay and improved rehabilitation. However these results are derived mainly from one study. Conservative treatment will be acceptable where modern surgical facilities are unavailable, and will result in a reduction in complications associated with surgery, but rehabilitation is likely to be slower and limb deformity more common. Although further randomised trials would provide more robust data, they may be difficult to mount.

Adult↗
PubMed1976

Perception as a possible source of conservation: evidence for length conservation.

In conservation problems, it is commonly assumed that equivalence judgments are not facilitated by observation of the stimuli following transformation. The reverse is usually assumed to be the case. These assumptions were tested in a training experiment. Perceptual counterparts of a series of conservation of length tests were presented to subjects who were catagorized as conservers or nonconservers on conservations of length pretests, and to conservers and nonconservers given conservation of length training. Perceptual performance of the untrained nonconservers was significantly worse than that of the other 3 groups, that is, trained nonconservers, untrained conservers, and trained conservers. These findings are interpreted as consistent with the hypothesis that conservation is attained with the support of perception, not in spite of it.

Child↗
PubMed2006

Conservation of intrinsic disorder in protein domains and families: II. functions of conserved disorder.

Regions of conserved disorder prediction (CDP) were found in protein domains from all available InterPro member databases, although with varying frequency. These CDP regions were found in proteins from all kingdoms of life, including viruses. However, eukaryotes had 1 order of magnitude more proteins containing long disordered regions than did archaea and bacteria. Sequence conservation in CDP regions varied, but was on average slightly lower than in regions of conserved order. In some cases, disordered regions evolve faster than ordered regions, in others they evolve slower, and in the rest they evolve at roughly the same rate. A variety of functions were found to be associated with domains containing conserved disorder. The most common were DNA/RNA binding, and protein binding. Many ribosomal proteins also were found to contain conserved disordered regions. Other functions identified included membrane translocation and amino acid storage for germination. Due to limitations of current knowledge as well as the methodology used for this work, it was not determined whether these functions were directly associated with the predicted disordered region. However, the functions associated with conserved disorder in this work are in agreement with the functions found in other studies to correlate to disordered regions. We have established that intrinsic disorder may be more common in bacterial and archaeal proteins than previously thought, but this disorder is likely to be used for different purposes than in eukaryotic proteins, as well as occurring in shorter stretches of protein. Regions of predicted disorder were found to be conserved within a large number of protein families and domains. Although many think of such conserved domains as being ordered, in fact a significant number of them contain regions of disorder that are likely to be crucial to their functions.

Amino Acid Sequence↗
PubMed2000

Conservative management of post prostatectomy incontinence.

BACKGROUND: Urinary incontinence after prostatectomy is a common problem. Conservative management of this condition includes pelvic floor muscle training, biofeedback, electrical stimulation using a rectal electrode, transcutaneous electrical nerve stimulation, or a combination of methods. OBJECTIVES: To assess the effects of conservative management for urinary incontinence after transurethral, suprapubic, radical retropubic or perineal prostatectomy. SEARCH STRATEGY: The Cochrane Incontinence Group's trials register, Medline, Cinahl, Embase, PsycLit and ERIC all up to January 1999, and reference lists of relevant articles. We contacted investigators to locate studies and we handsearched the following conference proceedings: American Urological Association (1989-1999); Society of Urologic Nurses and Associates (1991-1998); Wound Ostomy and Continence Nurses (1996-1999); and International Continence Society (1980-1998). Date of most recent searches: January 1999. SELECTION CRITERIA: Randomised or quasi-randomised trials which evaluated conservative management aimed at improving urinary continence after prostatectomy. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed the methodological quality of studies and abstracted data from included trials onto a standard form. MAIN RESULTS: Only five randomised trials were identified which included 365 men, each evaluating different treatments, and all studying men after radical prostatectomy. The trials were of moderate quality and data were not available for many of the pre-stated outcomes. Confidence intervals for both dichotomous and continuous data were wide; it was not possible to reliably identify or rule out a useful effect. Men's symptoms tended to improve over time, irrespective of management. REVIEWER'S CONCLUSIONS: The value of the various approaches to conservative management of post prostatectomy incontinence remains uncertain. Further well designed trials are needed.

Biofeedback, Psychology↗
PubMed1986

Conservation of kinetoplastid minicircle characteristics without nucleotide sequence conservation.

The nucleotide sequence and restriction fragment electrophoretic mobility of four minicircles from the kinetoplast DNA of Trypanosoma brucei were determined. Each minicircle possesses an approximately 130 base pair conserved sequence which occurs in other African trypanosome minicircles and contains a 13 base pair sequence that is conserved among kinetoplastid genera [Kidane et al. (1984) Gene 27, 265-277]. A sequence located adjacent to the conserved sequence conserves purine versus pyrimidine strand bias, but not nucleotide sequence, and contains periodic oligo(dA) tracts. Minicircle fragments containing the conserved sequence and adjacent segment exhibited anomalous electrophoretic mobility in polyacrylamide gels. The position of the oligo(dA) tracts in the fragments appears to influence this anomalous mobility. The presence of conserved features independent of conserved nucleotide sequence and the lack of conserved open reading frames among these minicircles suggests that minicircles may have a function other than encoding protein.

Animals↗
PubMed2005

Sequence conservation, relative isoform frequencies, and nonsense-mediated decay in evolutionarily conserved alternative splicing.

Studies of expressed sequence tag data sets have revealed large numbers of splicing variants for human genes, but it remains challenging to distinguish functionally important variants from aberrant splicing, clarify the nature of the alternative functions, and understand the signals that regulate splicing choices. To help address these issues, we have constructed and analyzed a large data set of 1,478 exon-skipping alternative splicing (AS) variants evolutionarily conserved in human and mouse. In about one-fifth of cases, one isoform appears subject to nonsense-mediated mRNA decay (NMD), supporting the idea that a major role of AS is to regulate gene expression; one-quarter of these NMD-inducing cases involve a conserved exon whose apparent sole purpose is to mediate destruction of the message when included. We explore sequence conservation likely related to splicing regulation, using in part a measure of the overall amount of conserved information in a sequence, and find that the increased conservation that has been observed within AS exons primarily affects synonymous sites, suggesting that regulatory signals significantly constrain synonymous substitution rates. We show that a lower frequency of the inclusion isoform relative to the exclusion isoform tends to be associated with weaker splice site signals, smaller exon size, and higher intronic sequence conservation, and provide evidence that all of these factors are under selection to control relative isoform frequencies. Some conserved instances of AS appear to represent aberrant splicing events that by chance have occurred in both species, and we develop a nonparametric likelihood approach to identify these.

Alternative Splicing↗
PubMed2006

Highly conserved syntenic blocks at the vertebrate Hox loci and conserved regulatory elements within and outside Hox gene clusters.

Hox genes in vertebrates are clustered, and the organization of the clusters has been highly conserved during evolution. The conservation of Hox clusters has been attributed to enhancers located within and outside the Hox clusters that are essential for the coordinated "temporal" and "spatial" expression patterns of Hox genes in developing embryos. To identify evolutionarily conserved regulatory elements within and outside the Hox clusters, we obtained contiguous sequences for the conserved syntenic blocks from the seven Hox loci in fugu and carried out a systematic search for conserved noncoding sequences (CNS) in the human, mouse, and fugu Hox loci. Our analysis has uncovered unusually large conserved syntenic blocks at the HoxA and HoxD loci. The conserved syntenic blocks at the human and mouse HoxA and HoxD loci span 5.4 Mb and 4 Mb and contain 21 and 19 genes, respectively. The corresponding regions in fugu are 16- and 12-fold smaller. A large number of CNS was identified within the Hox clusters and outside the Hox clusters spread over large regions. The CNS include previously characterized enhancers and overlap with the 5' global control regions of HoxA and HoxD clusters. Most of the CNS are likely to be control regions involved in the regulation of Hox and other genes in these loci. We propose that the regulatory elements spread across large regions on either side of Hox clusters are a major evolutionary constraint that has maintained the exceptionally long syntenic blocks at the HoxA and HoxD loci.

Animals↗
PubMed2002

A multidomain TIGR/olfactomedin protein family with conserved structural similarity in the N-terminal region and conserved motifs in the C-terminal region.

Based on the similarity between the TIGR (trabecular-meshwork inducible glucocorticoid response) (also known as myocilin) and olfactomedin protein families identified throughout the length of the TIGR protein, we have identified more distantly related proteins to determine the elements essential to the function/structure of the TIGR and olfactomedin proteins. Using a sequence walk method and the Shotgun program, we have identified a family including 31 olfactomedin domain-containing sequences. Multiple sequence alignments and secondary structure analyses were used to identify conserved sequence elements. Pairwise identity in the olfactomedin domain ranges from 8 to 64%, with an average pairwise identity of 24%. The N-terminal regions of the proteins fall into two subgroups, one including the TIGR and olfactomedin families and another group of apparently unrelated domains. The TIGR and olfactomedin sequences display conserved motifs including a residual leucine zipper region and maintain a similar secondary structure throughout the N-terminal region. The correlation between conserved elements and disease-associated mutations and apparent polymorphisms in human TIGR was also examined to evaluate the apparent importance of conserved residues to the function/structure of TIGR. Several residues have been identified as essential to the function and/or structure of the human TIGR protein based on their degree of conservation across the family and their implication in the pathogenesis of primary open-angle glaucoma. Additionally, we have identified a group of chitinase sequences containing several of the highly conserved motifs present in the C-terminal region of the olfactomedin domain-containing sequences.

Algorithms↗
PubMed2006

Conserved distances between vertebrate highly conserved elements.

High numbers of sequence element with very high (>95%) sequence conservation between the human and other vertebrate genomes have been reported and ascribed putative cis-regulatory functions. We have investigated the structural relationships between such elements in mammalian genomes and find that not only their sequences, but also the distances between them are significantly (P<2.2x10(-16)) more conserved than corresponding distances between orthologous protein-coding genes or between exons within these genes. Regions of largely conserved distance between consecutive highly conserved elements (HCE) generally overlap previously identified HCE clusters, but may be far longer (up to 20 Mb) and possibly cover close to 25% of the human genome sequence. Similar conservation of distance is found between bird (chicken) and mammalian genomes and is also discernible in comparisons between fish and mammals. The data suggest either that a substantial amount of essential (functionally active) elements with lower sequence conservation occupy the space between the HCEs or that distance itself is an important factor in transcriptional regulation or chromatin modelling.

Animals↗
PubMed2006

Conservation Biology and real-world conservation.

In the 20 years since Conservation Biology was launched with the aim of disseminating scientific knowledge to help conserve biodiversity and the natural world, our discipline has hugely influenced the practice of conservation. But we have had less impact outside the profession itself and we have not transformed that practice into an enterprise large enough to achieve our conservation goals. As we look to the next 20 years, we need to become more relevant and important to the societies in which we live. To do so, the discipline of conservation biology must generate answers even when full scientific knowledge is lacking, structure scientific research around polices and debates that influence what we value as conservationists, go beyond the certitude of the biological sciences into the more contextual debates of the social sciences, engage scientifically with human-dominated landscapes, and address the question of how conservation can contribute to the improvement of human livelihoods and the quality of human life.

Conservation of Natural Resources↗
PubMed1991

Changing indications for breast conserving therapy: proportion of patients with operable breast cancer suitable for breast conservation.

The changes in indication for breast conserving therapy and the proportion of operable stage-I and stage-II breast cancers suitable for breast conserving therapy were studied in three time periods. The percentage of patients treated with breast conserving therapy gradually increased through the years: 77/199 (39%) in 1980-1981, 122/245 (50%) in 1985-1987, and 168/305 (55%) in 1987-1989. Using the actual selection criteria more patients might have been candidates for breast conserving therapy: 69, 64 and 59 per cent respectively. In the period 1987-1989 almost all patients who were considered good candidates for breast conserving therapy had a breast sparing procedure. Indications widened in relation to age limit (less than or equal to 70 years) and, over the years, more factors became relative contra-indications: very young age, presence of extensive intra-ductal component, data from mammography (multicentricity, size and aspect of the lesion). About 40 per cent of the patients were no appropriate candidates for breast conserving therapy. This percentage would be higher when operable stage-III patients would have been included.

Age Factors↗