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Genetic evaluation of the efficacy of in situ and ex situ conservation of Parashorea chinensis (Dipterocarpaceae) in Southwestern China.

The majority of research in genetic diversity yields recommendations rather than actual conservation achievements. We assessed the efficacy of actual in situ and ex situ efforts to conserve Parashorea chinensis (Dipterocarpaceae) against the background of the geographic pattern of genetic variation of this species. Samples from seven natural populations, including three in a nature reserve, and one ex situ conservation population were studied. Across the natural populations, 47.8% of RAPD loci were polymorphic; only 20.8% on average varied at the population level. Mean population genetic diversity was 0.787 within natural populations and 1.410 for the whole species. Significant genetic differentiation among regions and isolation by distance were present on larger scales (among regions). AMOVA revealed that the majority of the among-population variation occurred among regions rather than among populations within regions. Regression analysis, Mantel test, principal coordinates analysis, and cluster analysis consistently demonstrated increasing genetic isolation with increasing geographic distance. Genetic differentiation within the region was quite low compared to that among regions. Multilocus spatial autocorrelation analysis of these three populations revealed random distribution of genetic variation in two populations, but genetic clustering was detected in the third population. The ex situ conserved population contained a medium level of genetic variation compared with the seven natural populations; it contained 77.1% of the total genetic variation of this species and 91% of the moderate to high frequency RAPD fragments (f > 0.05). Exclusive bands were detected in natural populations, but none were found in the ex situ conserved population. The populations protected in the nature reserve contained most of the genetic variation of the whole species, with 81.4% of the total genetic variation and 95.7% of the fragments with moderate to high frequency (f > 0.05) of this species conserved. The results show that the ex situ conserved population does not contain enough genetic variation to meet the need of release in the future, and that more extensive ex situ sampling in natural populations TY, NP, HK, and MG is needed. The in situ conserved population contains representative genetic variation to maintain long-term survival and evolutionary processes of P. chinensis.

Animals↗

Conservation physiology.

Conservation biologists increasingly face the need to provide legislators, courts and conservation managers with data on causal mechanisms underlying conservation problems such as species decline. To develop and monitor solutions, conservation biologists are progressively using more techniques that are physiological. Here, we review the emerging discipline of conservation physiology and suggest that, for conservation strategies to be successful, it is important to understand the physiological responses of organisms to their changed environment. New physiological techniques can enable a rapid assessment of the causes of conservation problems and the consequences of conservation actions.

Adaptation, Physiological↗

Greater GNN pattern bias in sequence elements encoding conserved residues of ancient proteins may be an indicator of amino acid composition of early proteins.

The possibility that RNY pattern bias in extant sequences is a remnant of more pronounced bias of this type in early ancestors was investigated. To this end, conserved residues (those residues for which the inferred ancestral and known descendant amino acids are identical) and non-conserved residues of ancient proteins dating to the Last Universal Ancestor were identified within six species: two archaea, two eubacteria and two eukaryotes. Bias within sequence elements encoding each subset of residues, conserved and non-conserved, was then determined. In all species, GNN bias is greater within conserved than non-conserved sequence elements, whereas ANN is not. This difference is statistically significant in all six species examined. Since the relative mutability of the GNN-encoded amino acids does not explain the greater bias in conserved sequences, it is concluded that early sequences probably possessed a strong GNN bias. It is suggested that this bias may be a consequence of the GNN codons being the first introduced into the genetic code. Although NNY bias is also greater within conserved sequence elements of the six species, that difference is statistically significant in only half of them. Therefore, the evidence for early NNY bias remains inconclusive. The findings of this study do not support the proposal of Diaz-Lazcoz et al. (J. Mol. Biol. 250 (1995) 123) that the codons of the TCN four-codon block were the first assigned to serine during the evolution of the genetic code.

Amino Acids↗

Freshwater biodiversity: importance, threats, status and conservation challenges.

Freshwater biodiversity is the over-riding conservation priority during the International Decade for Action - 'Water for Life' - 2005 to 2015. Fresh water makes up only 0.01% of the World's water and approximately 0.8% of the Earth's surface, yet this tiny fraction of global water supports at least 100000 species out of approximately 1.8 million - almost 6% of all described species. Inland waters and freshwater biodiversity constitute a valuable natural resource, in economic, cultural, aesthetic, scientific and educational terms. Their conservation and management are critical to the interests of all humans, nations and governments. Yet this precious heritage is in crisis. Fresh waters are experiencing declines in biodiversity far greater than those in the most affected terrestrial ecosystems, and if trends in human demands for water remain unaltered and species losses continue at current rates, the opportunity to conserve much of the remaining biodiversity in fresh water will vanish before the 'Water for Life' decade ends in 2015. Why is this so, and what is being done about it? This article explores the special features of freshwater habitats and the biodiversity they support that makes them especially vulnerable to human activities. We document threats to global freshwater biodiversity under five headings: overexploitation; water pollution; flow modification; destruction or degradation of habitat; and invasion by exotic species. Their combined and interacting influences have resulted in population declines and range reduction of freshwater biodiversity worldwide. Conservation of biodiversity is complicated by the landscape position of rivers and wetlands as 'receivers' of land-use effluents, and the problems posed by endemism and thus non-substitutability. In addition, in many parts of the world, fresh water is subject to severe competition among multiple human stakeholders. Protection of freshwater biodiversity is perhaps the ultimate conservation challenge because it is influenced by the upstream drainage network, the surrounding land, the riparian zone, and - in the case of migrating aquatic fauna - downstream reaches. Such prerequisites are hardly ever met. Immediate action is needed where opportunities exist to set aside intact lake and river ecosystems within large protected areas. For most of the global land surface, trade-offs between conservation of freshwater biodiversity and human use of ecosystem goods and services are necessary. We advocate continuing attempts to check species loss but, in many situations, urge adoption of a compromise position of management for biodiversity conservation, ecosystem functioning and resilience, and human livelihoods in order to provide a viable long-term basis for freshwater conservation. Recognition of this need will require adoption of a new paradigm for biodiversity protection and freshwater ecosystem management - one that has been appropriately termed 'reconciliation ecology'.

Animals↗

Conserved residues and their role in the structure, function, and stability of acyl-coenzyme A binding protein.

In the family of acyl-coenzyme A binding proteins, a subset of 26 sequence sites are identical in all eukaryotes and conserved throughout evolution of the eukaryotic kingdoms. In the context of the bovine protein, the importance of these 26 sequence positions for structure, function, stability, and folding has been analyzed using single-site mutations. A total of 28 mutant proteins were analyzed which covered 17 conserved sequence positions and three nonconserved positions. As a first step, the influence of the mutations on the protein folding reaction has been probed, revealing a folding nucleus of eight hydrophobic residues formed between the N- and C-terminal helices [Kragelund, B. B., et al. (1999) Nat. Struct. Biol. (In press)]. To fully analyze the role of the conserved residues, the function and the stability have been measured for the same set of mutant proteins. Effects on function were measured by the extent of binding of the ligand dodecanoyl-CoA using isothermal titration calorimetry, and effects on protein stability were measured with chemical denaturation followed by intrinsic tryptophan and tyrosine fluorescence. The sequence sites that have been conserved for direct functional purposes have been identified. These are Phe5, Tyr28, Tyr31, Lys32, Lys54, and Tyr73. Binding site residues are mainly polar or charged residues, and together, four of these contribute approximately 8 kcal mol-1 of the total free energy of binding of 11 kcal mol-1. The sequence sites conserved for stability of the structure have likewise been identified and are Phe5, Ala9, Val12, Leu15, Leu25, Tyr28, Lys32, Gln33, Tyr73, Val77, and Leu80. Essentially, all of the conserved residues that maintain the stability are hydrophobic residues at the interface of the helices. Only one conserved polar residue, Gln33, is involved in stability. The results indicate that conservation of residues in homologous proteins may result from a summed optimization of an effective folding reaction, a stable native protein, and a fully active binding site. This is important in protein design strategies, where optimization of one of these parameters, typically function or stability, may influence any of the others markedly.

Acyl Coenzyme A↗

Noncoding sequences conserved in a limited number of mammals in the SIM2 interval are frequently functional.

Cross-species DNA sequence comparison is a fundamental method for identifying biologically important elements, because functional sequences are evolutionarily conserved, wheres nonfunctional sequences drift. A recent genome-wide comparison of human and mouse DNA discovered over 200,000 conserved noncoding sequences with unknown function. Multispecies DNA comparison has been proposed as a method to prioritize these conserved noncoding sequences for functional analysis based on the hypothesis that elements present in many species are more likely to be functional than elements present in limited numbers of species. Here, we perform a comparative analysis of the single-minded 2 (SIM2) gene interval on human chromosome 21 with horse, cow, pig, dog, cat, and mouse DNA. We classify conserved sequences based on the number of mammals in which they are present, and experimentally test sequences in each class for function. As hypothesized, conserved sequences present in many mammals are frequently functional. Additionally, we demonstrate that sequences conserved in a limited number of mammals are also frequently functional. Examination of genomic deletions in chimpanzee and rhesus macaque DNA showed that several putatively functional conserved noncoding human sequences were absent in these primates. These findings suggest that functional conserved noncoding human sequences can be missing in other mammals, even closely related primate species.

Animals↗

Genome-wide regulatory complexity in yeast promoters: separation of functionally conserved and neutral sequence.

To gauge the complexity of gene regulation in yeast, it is essential to know how much promoter sequence is functional. Conservation across species can be a sensitive means of detecting functional sequences, provided that the significance of conservation can be accurately calibrated with the local neutral mutation rate. By analyzing yeast coding and promoter sequences, we find that neutral mutation rates in yeast are uniform genome-wide, in contrast to mammals, where neutral mutation rates vary along chromosomes. We develop an approach that uses this uniform rate to estimate the amount of promoter sequence under purifying selection. This amount is approximately 30%, corresponding to roughly 90 bp for a typical promoter. Furthermore, using a hidden Markov model, we are able to separate each promoter into distinct high and low conservation regions. Known regulatory motifs are strongly biased toward high conservation regions, while low conservation regions have mutation rates similar to that of the neutral background. Certain Gene Ontology groupings of genes (e.g., Carbohydrate Metabolism) have large amounts of high conservation sequence, suggesting complexity in their transcriptional regulation. Others (e.g., RNA Processing) have little high conservation sequence and are likely to be simply regulated. The separation of functionally conserved sequence from the neutral background allows us to estimate the complexity of cis-regulation on a genomic scale.

Base Sequence↗

Are protein-protein interfaces more conserved in sequence than the rest of the protein surface?

Protein interfaces are thought to be distinguishable from the rest of the protein surface by their greater degree of residue conservation. We test the validity of this approach on an expanded set of 64 protein-protein interfaces using conservation scores derived from two multiple sequence alignment types, one of close homologs/orthologs and one of diverse homologs/paralogs. Overall, we find that the interface is slightly more conserved than the rest of the protein surface when using either alignment type, with alignments of diverse homologs showing marginally better discrimination. However, using a novel surface-patch definition, we find that the interface is rarely significantly more conserved than other surface patches when using either alignment type. When an interface is among the most conserved surface patches, it tends to be part of an enzyme active site. The most conserved surface patch overlaps with 39% (+/- 28%) and 36% (+/- 28%) of the actual interface for diverse and close homologs, respectively. Contrary to results obtained from smaller data sets, this work indicates that residue conservation is rarely sufficient for complete and accurate prediction of protein interfaces. Finally, we find that obligate interfaces differ from transient interfaces in that the former have significantly fewer alignment gaps at the interface than the rest of the protein surface, as well as having buried interface residues that are more conserved than partially buried interface residues.

Amino Acid Sequence↗

"A mission-driven discipline": the growth of conservation biology.

Conservation biology emerged in the mid-1980s, drawing on established disciplines and integrating them in pursuit of a coherent goal: the protection and perpetuation of the Earth's biological diversity. Opportunistic in its borrowing and application of knowledge, conservation biology had its roots within the established biological sciences and resource management disciplines but has continually incorporated insights from the empirical experience of resource managers, from the social sciences and humanities, and from diverse cultural sources. The Society for Conservation Biology (SCB) has represented the field's core constituency, while expanding that constituency in keeping with the field's integrative spirit. Conservation Biology has served as SCB's flagship publication, promoting research, dialog, debate, and application of the field's essential concepts. Over the last 20 years the field, SCB, and the journal have evolved to meet changing conservation needs, to explore gaps in our knowledge base, to incorporate new information from related fields, to build professional capacity, and to provide expanded opportunities for international participation. In turn, the field, SCB, and journal have prompted change in related fields, organizations, and publications. In its dedication to advancing the scientific foundations of biodiversity conservation and placing that science at the service of society in a world whose variety, wildness, and beauty we care for conservation biology represents both a continuation and radical reconfiguration of the traditional relationship between science and conservation.

Conservation of Natural Resources↗

The NarX and NarQ sensor-transmitter proteins of Escherichia coli each require two conserved histidines for nitrate-dependent signal transduction to NarL.

The NarX, NarQ, and NarL proteins of Escherichia coli constitute a two-component regulatory system that controls the expression of a number of anaerobic respiratory pathway genes in response to nitrate. NarX and NarQ are sensor-transmitter proteins that can independently detect the presence of nitrate in the cell environment and transmit this signal to the response regulator, NarL. Upon activation, NarL binds DNA and modulates the expression of its target genes by the repression or activation of transcription. NarX and NarQ each contain a conserved histidine residue that corresponds to the site of autophosphorylation of other sensor-transmitter proteins. They also contain a second conserved histidine residue that is present in the NarX, NarQ, UhpB, DegS, and ComP subfamily of sensor-transmitter proteins. The second histidine is located near a universally conserved asparagine residue, the role of which in signal transduction is unknown. To investigate the role of these conserved amino acids in the NarX and NarQ proteins, we mutated the narX and narQ genes by site-directed mutagenesis. In vivo, each mutation severely impaired NarL-dependent activation or repression of reporter gene expression in response to nitrate. The in vivo data suggest that the environmental signal nitrate controls both the kinase and phosphatase activities of the two sensor-transmitter proteins. The altered NarX and NarQ proteins were purified and shown to be defective in their ability to autophosphorylate in the presence of [gamma-32P]ATP. The NarX and NarQ proteins with amino acid substitutions at the first conserved histidine position were also unable to dephosphorylate NarL-phosphate in vitro. In contrast, the proteins containing amino acid substitutions at the second conserved histidine or at the conserved asparagine residue retained NarL-phosphate dephosphorylation activity. The conserved histidine and asparagine residues are essential for NarX and NarQ function, and this suggests that other two-component sensor-transmitter proteins may function in a similar fashion.

Amino Acid Sequence↗

Mapping the economic costs and benefits of conservation.

Resources for biodiversity conservation are severely limited, requiring strategic investment. Understanding both the economic benefits and costs of conserving ecosystems will help to allocate scarce dollars most efficiently. However, although cost-benefit analyses are common in many areas of policy, they are not typically used in conservation planning. We conducted a spatial evaluation of the costs and benefits of conservation for a landscape in the Atlantic forests of Paraguay. We considered five ecosystem services (i.e., sustainable bushmeat harvest, sustainable timber harvest, bioprospecting for pharmaceutical products, existence value, and carbon storage in aboveground biomass) and compared them to estimates of the opportunity costs of conservation. We found a high degree of spatial variability in both costs and benefits over this relatively small (approximately 3,000 km(2)) landscape. Benefits exceeded costs in some areas, with carbon storage dominating the ecosystem service values and swamping opportunity costs. Other benefits associated with conservation were more modest and exceeded costs only in protected areas and indigenous reserves. We used this cost-benefit information to show that one potential corridor between two large forest patches had net benefits that were three times greater than two otherwise similar alternatives. Spatial cost-benefit analysis can powerfully inform conservation planning, even though the availability of relevant data may be limited, as was the case in our study area. It can help us understand the synergies between biodiversity conservation and economic development when the two are indeed aligned and to clearly understand the trade-offs when they are not.

Biodiversity↗

Conservation planning for ecosystem services.

Despite increasing attention to the human dimension of conservation projects, a rigorous, systematic methodology for planning for ecosystem services has not been developed. This is in part because flows of ecosystem services remain poorly characterized at local-to-regional scales, and their protection has not generally been made a priority. We used a spatially explicit conservation planning framework to explore the trade-offs and opportunities for aligning conservation goals for biodiversity with six ecosystem services (carbon storage, flood control, forage production, outdoor recreation, crop pollination, and water provision) in the Central Coast ecoregion of California, United States. We found weak positive and some weak negative associations between the priority areas for biodiversity conservation and the flows of the six ecosystem services across the ecoregion. Excluding the two agriculture-focused services-crop pollination and forage production-eliminates all negative correlations. We compared the degree to which four contrasting conservation network designs protect biodiversity and the flow of the six services. We found that biodiversity conservation protects substantial collateral flows of services. Targeting ecosystem services directly can meet the multiple ecosystem services and biodiversity goals more efficiently but cannot substitute for targeted biodiversity protection (biodiversity losses of 44% relative to targeting biodiversity alone). Strategically targeting only biodiversity plus the four positively associated services offers much promise (relative biodiversity losses of 7%). Here we present an initial analytical framework for integrating biodiversity and ecosystem services in conservation planning and illustrate its application. We found that although there are important potential trade-offs between conservation for biodiversity and for ecosystem services, a systematic planning framework offers scope for identifying valuable synergies.

Biodiversity↗

[Conservation priorities for plant species of forest-meadow ecotone in Sanjiangyuan Nature Reserve].

Based on field survey, information collection and experts consultation, the quantitative grading index system and assessment standards for preference conservation of rare and endangered plant species of forest-meadow ecotone in Sanjiangyuan Nature Reserve were established by using the methods and principles of systematical analysis. The quantitative grading index system included endangered coefficient, genetic coefficient, and useful value coefficient. In addition, 10 indicators used to evaluate endangered grading and conservation priorities sequenc, were also included in 3 subsystems respectively. Furthermore, the weights of 3 subsystem and 10 indicators were given through experts consultation and analytic hierarchy process. Endangered coefficient and conservation priorities coefficient, which respectively described the endangered grading, and preferential conservation of plant species were calculated by mathematic models and computer program. Contrasting to the standards of endangered grading and conservation priorities for plant species, we quantitatively evaluated the status of endangered and conservation priorities of plant species. The results showed that the number of endangered species was 4, vulnerable species 68, lower risk species 179, safety species 695; the number of the first class species was 8, the second class species 78, the third class species 164, and the delayed conservation species 696. Finally, we discussed the problems of indicator system and its weight, the relationship between endangered grading and conservation priorities sequence, and the spatial scale problem of plant species assessment.

Biodiversity↗

Conservation of polyproline II helices in homologous proteins: implications for structure prediction by model building.

Left-handed polyproline II (PPII) helices commonly occur in globular proteins in segments of 4-8 residues. This paper analyzes the structural conservation of PPII-helices in 3 protein families: serine proteinases, aspartic proteinases, and immunoglobulin constant domains. Calculations of the number of conserved segments based on structural alignment of homologous molecules yielded similar results for the PPII-helices, the alpha-helices, and the beta-strands. The PPII-helices are consistently conserved at the level of 100-80% in the proteins with sequence identity above 20% and RMS deviation of structure alignments below 3.0 A. The most structurally important PPII segments are conserved below this level of sequence identity. These results suggest that the PPII-helices, in addition to the other 2 secondary structure classes, should be identified as part of structurally conserved regions in proteins. This is supported by similar values for the local RMS deviations of the aligned segments for the structural classes of PPII-helices, alpha-helices, and beta-strands. The PPII-helices are shown to participate in supersecondary elements such as PPII-helix/alpha-helix. The conservation of PPII-helices depends on the conservation of a supersecondary element as a whole. PPII-helices also form links, possibly flexible, in the interdomain regions. The role of the PPII-helices in model building by homology is 2-fold; they serve as additional conserved elements in the structure allowing improvement of the accuracy of a model and provide correct chain geometry for modeling of the segments equivalenced to them in a target sequence. The improvement in model building is demonstrated in 2 test studies.

Amino Acid Sequence↗

Creating Biodiversity Partnerships: The Nature Conservancy's Perspective

/ The Nature Conservancy is an international organization dedicated to the mission of conserving biodiversity throughout the world. By working in a nonconfrontational manner, an approach that has promoted both government and corporate sponsorship of its activities, The Nature Conservancy has developed symbiotic relationships with many electric utility companies. Drawing on the organization's experiences, and the experiences of the author as the President and Chief Executive Officer of The Nature Conservancy, five broad areas of cooperation between conservation organizations and the utility industry are explored: land-management agreements, mitigation projects, conflict-avoidance programs, program support, and volunteer activities. The paper is concluded with comments on the future trends of biodiversity conservation, challenging the electric utility industry to become involved with conservation efforts by forming cooperative partnerships.KEY WORDS: Biodiversity; Conservation; Electricity; Environment; Partnership; Utility

Journal Article↗

Breast-conserving therapy versus modified radical mastectomy in the treatment of early breast cancer in Japan.

BACKGROUND: Breast-conserving therapy has been widely utilized as a treatment option for women with early breast cancer. However, no randomized study comparing modified radical mastectomy and breast-conserving therapy has been conducted in Japan. METHODS: Two hundred and twenty-eight Japanese women with early breast cancer enrolled in the Gunma Breast Conserving Therapy Study between 1991 and 1994 were examined to determine whether there is any difference in disease-free survival or overall survival between radical mastectomy and breast-conserving therapy. After informed consent was obtained, a total of 119 patients underwent breast-conserving therapy and 109 underwent mastectomy. RESULTS: Mastectomy was a more frequently utilized treatment than breast-conserving therapy in patients with clinical stage II lesions, older age, larger tumor size or shorter distance between tumor and nipple. The mean follow-up period for all patients was 81 months (median 86 months). There was no significant difference in overall survival or disease-free survival between breast-conserving therapy and mastectomy even after adjusting for the clinical stage of the disease. A multivariate analysis of tumor size, lymph node status, estrogen receptor status and operation method using the Cox proportion hazard model confirmed that only lymph node status was an independent prognostic factor. CONCLUSION: Breast-conserving therapy is comparable to modified radical mastectomy in overall survival and disease-free survival.

Adult↗

Steps in the processing of Ad2 mRNA: poly(A)+ nuclear sequences are conserved and poly(A) addition precedes splicing.

The conservation of nuclear Ad2 sequences during nucleocytoplasmic transport has been estimated from the accumulation of 3H-uridine in nuclear and cytoplasmic Ad2-specific RNA from the major late transcription unit. From 10-28% is conserved of the total Ad2 nuclear RNA synthesized from each of five regions of the genome that specify groups of 3' co-terminal mRNAs. The sum of the conservation of all the regions was equivalent to 100%, signifying the conservation of at least a part of each transcript or all of about one fifth to one sixth of the transcripts. The conservation of poly(A)+ Ad2 nuclear RNA is about 4 times greater than of total Ad2 nuclear RNA, approaching 100% conservation of poly(A)+ nuclear sequences. Since each mRNA contains three "spliced" sequences that are probably encoded only once per transcript, these data on conservation of the Ad2 sequences suggest that each transcriptional event from the 16-99 transcription unit gives rise to one of a possible 13-14 mRNA molecules with destruction of the remainder of the transcribed RNA. The portion which is conserved resides next to the region to which which poly(A) is added. Three models for the choice of poly(A) sites were considered: termination at the poly(A) site, cleavage shortly after synthesis of one of the sites before transcription was complete, and cleavage after completion of transcription. The first model was ruled out by the demonstration of equimolar synthesis over the 16-99 region. The second model is strongly supported because 3H-uridine label appears equally rapidly in the time range 2-10 min in each of the five 3' poly(A) addition sites, whereas chain completion before cleavage would lead to a faster appearance of label in the most promoter-distal site. Furthermore, briefly labeled RNA molecules extending from 16 to each of several poly(A) addition sites were the first poly(A)- terminated 3H-uridine-labeled molecules detected, demonstrating that poly(A) addition precedes splicing. The choice of which mRNA emerges from each transcriptional event would appear to depend upon first choosing one of five 3' mRNA ends followed by a 5' splicing event.

Adenoviruses, Human↗

Urinary complications of Miami pouch: trend of conservative management.

OBJECTIVE: Continent urinary diversions have become popular among gynecologic oncologists. Much information has been gained concerning the complications and current management of patients with continent ileocolonic reservoirs. The high mortality rate associated with reoperation has led clinicians to adopt a trend toward conservative means of management. The purpose of this study was to evaluate the applicability of conservative management of complications related to the creation of the continent ileocolonic reservoir Miami pouch. STUDY DESIGN: Patients who underwent creation of the Miami pouch at the Division of Gynecologic Oncology, University of Miami School of Medicine, since 1988 have been included in this study. Management of complications, with particular emphasis on the conservative treatment, has been reviewed in detail for each patient. Open surgery and conservative treatment have been compared. RESULTS: Seventy-seven patients underwent creation of the Miami pouch from February 1988 to September 1997. Sixty (77.9%) patients were affected by recurrent cervical cancer; 72 (93.5%) were previously radiated. The perioperative mortality rate was 11.7% (9 patients). Six of these patients died as a result of sepsis; all of them underwent reoperation at least once. The most common urinary complications were ureteral stricture or obstruction (22.1%), difficult catheterization (19.5%), and pyelonephritis (13%). Conservative management strategies used for these complications included percutaneous nephrostomy, stent placement, balloon dilatation, radiologically (ultrasonography, fluoroscopy, computed tomography) guided placement of catheters, and antibiotic treatment. Eighty percent of the complications associated with the ileocolonic reservoir were resolved with conservative treatment, whereas 16.9% required surgical revision. CONCLUSION: On the basis of these findings, conservative management of urinary reservoir complications should always be considered before surgical intervention is attempted. The exact time to engage in open revision should be individualized on the basis of the clinical condition of each patient. It is our belief that the conservative approach should be instituted whenever possible but surgical intervention not be delayed when absolutely indicated.

Adult↗