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Reintroduction
Terms modified by Reintroduction Selected AbstractsReduced FAS transcription in clones of U937 cells that have acquired resistance to Fas-induced apoptosisFEBS JOURNAL, Issue 2 2009Jeanette Blomberg Susceptibility to cell death is a prerequisite for the elimination of tumour cells by cytotoxic immune cells, chemotherapy or irradiation. Activation of the death receptor Fas is critical for the regulation of immune cell homeostasis and efficient killing of tumour cells by apoptosis. To define the molecular changes that occur during selection for insensitivity to Fas-induced apoptosis, a resistant variant of the U937 cell line was established. Individual resistant clones were isolated and characterized. The most frequently observed defect in the resistant cells was reduced Fas expression, which correlated with decreased FAS transcription. Clones with such reduced Fas expression also displayed partial cross-resistance to tumour necrosis factor-, stimulation, but the mRNA expression of tumour necrosis factor receptors was not decreased. Reintroduction of Fas conferred susceptibility to Fas but not to tumour necrosis factor-, stimulation, suggesting that several alterations could be present in the clones. The reduced Fas expression could not be explained by mutations in the FAS coding sequence or promoter region, or by silencing through methylations. Protein kinase B and extracellular signal-regulated kinase, components of signalling pathways downstream of Ras, were shown to be activated in some of the resistant clones, but none of the three RAS genes was mutated, and experiments using chemical inhibitors could not establish that the activation of these proteins was the cause of Fas resistance as described in other systems. Taken together, the data illustrate that Fas resistance can be caused by reduced Fas expression, which is a result of an unidentified mode of regulation. [source] Could we live with reintroduced large carnivores in the UK?MAMMAL REVIEW, Issue 3 2004CHARLES J. WILSON ABSTRACT 1.,Literature on the wolf Canis lupus, brown bear Ursus arctos and lynx Lynx lynx is reviewed to determine if sufficient semi-natural habitat exists in the UK for a viable population of any of these species and to assess the potential risks to human safety, livestock and economically valuable wildlife. Public attitudes to the recovery and reintroduction of some other mammals are also briefly reviewed. 2.,The large home range sizes and low population densities of large carnivores mean that the Scottish Highlands is the only UK region with the potential to support a viable population. Human population density is also lower in the Highlands and the density of wild ungulate prey higher than in many parts of Europe where large carnivores survive. 3.,Attacks on people have been recorded in Europe for healthy bears and for rabid bears and wolves but there are no reports of attacks by lynx. Bears are more carnivorous in the north of their range than in the south and although wild mammals seldom appear to be important prey serious predation of livestock can occur. Livestock predation is also reported for the wolf and the lynx but they appear to prefer wild prey if available. However, mass kills of up to 100 or more sheep are occasionally recorded for wolves. 4.,Attitudes to reintroductions and carnivores generally tend to be favourable amongst the general public, but negative amongst those most likely to be adversely affected. Fears for human safety and significant livestock predation with bears and wolves, respectively, suggest that reintroduction of these species is unlikely to be acceptable in the foreseeable future. Reintroduction of the lynx may be feasible but habitat suitability and potential impact on vulnerable native wildlife need to be assessed. Socio-economic and legal issues also need to be addressed before such a reintroduction is considered. [source] Rehabilitation of Stream Ecosystem Functions through the Reintroduction of Coarse Particulate Organic MatterRESTORATION ECOLOGY, Issue 1 2009Kane T. Aldridge Abstract In streams, coarse particulate organic matter (CPOM) acts as a substrate for microbial activity, which promotes nutrient retention. However, in urban areas, increased peak flows within streams lead to decreased retention of CPOM. The aim of this study was to investigate whether the reintroduction of CPOM, in the form of leaf litter, into a degraded urban stream would increase biofilm activity and phosphorus retention, two ecosystem functions that reflect the integrity of the ecosystem. Stream metabolism and nutrient retention were assessed in treated (T) and control (C) channels of the Torrens River Catchment, South Australia, before and after CPOM addition. Gross primary production and community respiration (CR) were measured as oxygen production and consumption within benthic chambers. Phosphorus retention was measured through a series of short-term filterable reactive phosphorus (FRP) addition experiments. Before CPOM addition, there were no differences in CR, but C retained 6.8% more FRP than T. After CPOM addition, CR was greater in T than in C (572 and 276 mg O2·m,2·day,1, respectively), and T retained 7.7% more FRP than C. The increase in FRP retention in T compared to C was attributed to phosphorus limitation of the CPOM and increased demand for phosphorus of the attached microbial heterotrophic community. The reintroduction of CPOM into degraded streams will be an important step in the restoration of stream metabolism and nutrient retention. Maintenance of CPOM may be achieved through restoration of riparian vegetation, a reduction in the increased peak flows, and rehabilitation of stream morphology. [source] Scream,embrace displays in wild black-horned capuchin monkeysAMERICAN JOURNAL OF PRIMATOLOGY, Issue 6 2008Jessica Lynch Alfaro Abstract Reintroduction of capuchin monkeys (Cebus apella) into their social group in captivity can elicit sirena screams and embraces. Captive scream,embrace displays are male biased, and females never perform sirena screams. One hypothesis is that scream,embrace displays serve a tension-reduction or reconciliatory function between males with conflicting interests. Alternatively, these displays may function to maintain strong affiliative bonds between friendly male dyads. Scream and/or embrace displays in wild Brazilian black-horned capuchins were analyzed for social and ecological contexts, behavioral components, and individuals involved. Seventy-two displays were observed during the 199-day study period. Among the 66 displays for which both members could be identified by sex, there were 42 occurrences of male,male dyads, 17 of male,female dyads, and seven of female,female dyads. Scream,embrace dyads were male,male pairs significantly more often than expected from group membership, and the , male was the only male to engage in scream,embrace displays with females. Female,female pairs did embrace, but never emitted sirena screams. Displays most commonly occurred in "reunion" contexts, primarily the reuniting of subgroups after hours or days out of contact, but also after intergroup encounters, and across groups in "intergroup" displays. Displays were rare, but socially contagious, and subgroup reunions could elicit multiple displays in rapid succession. Although the occurrence of screams and embraces was positively correlated, both behaviors also occurred independently, and their functions may be different. Male sirena screams may be honest advertisements of united alliances, directed toward a third party, whereas the embrace may be a risky affiliative signal, directed primarily within the dyad. Am. J. Primatol. 70:551,559, 2008. © 2008 Wiley-Liss, Inc. [source] Reevaluating suitable habitat for reintroductions: lessons learnt from the eastern barred bandicoot recovery programANIMAL CONSERVATION, Issue 2 2010C. N. Cook Abstract Reintroduction and translocation programs are widely used conservation tools but their success rates are low. Poor success rates for reintroduction programs are commonly attributed to insufficient knowledge of species' habitat requirements, especially if they are critically endangered. Yet conservation managers are frequently required to make decisions about suitable reintroduction sites when information is incomplete or uncertain. A widely used strategy to assist the selection of reintroduction sites , habitat suitability models , may rely on assumptions and simplifications to fill gaps in existing data. It is essential that these models are then evaluated and refined as new evidence becomes available. In this study, we examine the effectiveness of a reintroduction program based on habitat suitability modelling: that for the critically endangered eastern barred bandicoot Perameles gunnii in Australia. After collecting a variety of data from the reintroduction sites, we found that habitat preferences for this species could be accurately predicted using a simple logistic regression model within two predictor variables rather than the five previously used to select reintroduction sites. This made it possible to better focus limited resources on the most suitable reintroduction sites. We believe that building such a process of review into a reintroduction program can contribute to improving its success, while ensuring that scarce conservation resources are used more effectively. [source] Aberrant hypertrophy in Smad3-deficient murine chondrocytes is rescued by restoring transforming growth factor ,,activated kinase 1/activating transcription factor 2 signaling: A potential clinical implication for osteoarthritisARTHRITIS & RHEUMATISM, Issue 8 2010Tian-Fang Li Objective To investigate the biologic significance of Smad3 in the progression of osteoarthritis (OA), the crosstalk between Smad3 and activating transcription factor 2 (ATF-2) in the transforming growth factor , (TGF,) signaling pathway, and the effects of ATF-2 overexpression and p38 activation in chondrocyte differentiation. Methods Joint disease in Smad3-knockout (Smad3,/,) mice was examined by microfocal computed tomography and histologic analysis. Numerous in vitro methods including immunostaining, real-time polymerase chain reaction, Western blotting, an ATF-2 DNA-binding assay, and a p38 kinase activity assay were used to study the various signaling responses and protein interactions underlying the altered chondrocyte phenotype in Smad3,/, mice. Results In Smad3,/, mice, an end-stage OA phenotype gradually developed. TGF,-activated kinase 1 (TAK1)/ATF-2 signaling was disrupted in Smad3,/, mouse chondrocytes at the level of p38 MAP kinase (MAPK) activation, resulting in reduced ATF-2 phosphorylation and transcriptional activity. Reintroduction of Smad3 into Smad3,/, cells restored the normal p38 response to TGF,. Phosphorylated p38 formed a complex with Smad3 by binding to a portion of Smad3 containing both the MAD homology 1 and linker domains. Additionally, Smad3 inhibited the dephosphorylation of p38 by MAPK phosphatase 1 (MKP-1). Both ATF-2 overexpression and p38 activation repressed type X collagen expression in wild-type and Smad3,/, chondrocytes. P38 was detected in articular cartilage and perichondrium; articular and sternal chondrocytes expressed p38 isoforms ,, ,, and ,, but not ,. Conclusion Smad3 is involved in both the onset and progression of OA. Loss of Smad3 abrogates TAK1/ATF-2 signaling, most likely by disrupting the Smad3,phosphorylated p38 complex, thereby promoting p38 dephosphorylation and inactivation by MKP-1. ATF-2 and p38 activation inhibit chondrocyte hypertrophy. Modulation of p38 isoform activity may provide a new therapeutic approach for OA. [source] Wildfire Policy and Public Lands: Integrating Scientific Understanding with Social Concerns across LandscapesCONSERVATION BIOLOGY, Issue 4 2004MICHAEL P. DOMBECK administración de bosques; fuego no controlado; política; Servicio Forestal Estados Unidos; tierras públicas Abstract:,Efforts to suppress wildfires have become increasingly problematic in recent years as costs have risen, threats to firefighter safety have escalated, and detrimental impacts to ecosystems have multiplied. Wildfires that escape initial suppression often expand into large, high-intensity summer blazes. Lost is the legacy of smaller fires that likely burned outside extreme weather and fuel conditions and resulted in less severe impacts. Despite the recognized need for modifications to existing policies and practices, resource agencies have been slow to respond. The spread of exotic species, climate change, and increasing human development in wildlands further complicates the issue. New policies are needed that integrate social and ecological needs across administrative boundaries and broad landscapes. These policies should promote a continuum of treatments with active management and reduction of fuel hazard in wildland-urban interface zones and reintroduction of fire in wildlands. Management goals should focus on restoration of the long-term ecological health of the land. Projects that reduce fuel loads but compromise the integrity of soil, water supplies, or watersheds will do more harm than good in the long run. Despite significant ecological concerns, learning to live with fire remains primarily a social issue that will require greater political leadership, agency innovation, public involvement, and community responsibility. Resumen:,En años recientes, los esfuerzos para suprimir los fuegos no controlados se han vuelto cada vez más problemáticos por el incremento de costos, el aumento de las amenazas a la seguridad de bomberos y se la multiplicio, de los impactos perjudiciales a los ecosistemas. Los incendios que escapan la supresión inicial a menudo se expanden a grandes conflagraciones estivales de alta intensidad. Se ha perdido el legado de fuegos menores que probablemente se llevaban a cabo en condiciones climáticas y de combustible extremas que tenían impactos menos severos. A pesar del reconocimiento de la necesidad de modificaciones a las políticas y prácticas actuales, las agencias han respondido lentamente. La expansión de especies exóticas, el cambio climático y el incremento del desarrollo humano en áreas silvestres complican el problema aún más. Se requieren políticas nuevas que integren necesidades sociales y ecológicas más allá de límites administrativos y en paisajes amplios. Estas políticas deben promover un continuo de tratamientos con gestión activa y reducción de riesgo de combustión en la interfase área silvestre-urbana y la reintroducción de fuego en áreas silvestres. Las metas de la gestión deben enfocar en la restauración de la salud ecológica a largo plazo. Los proyectos que reducen la carga de combustible pero que comprometen la integridad del suelo, las reservas de agua o cuencas hidrológicas no serán de mucha utilidad en el largo plazo. A pesar de preocupaciones ecológicas significativas, aprender a vivir con fuego seguirá siendo un aspecto social que requerirá de mayor liderazgo político, innovación de agencias, participación del público y responsabilidad comunitaria. [source] Increased Behavioral Variation and the Calculation of Release Numbers for Reintroduction ProgramsCONSERVATION BIOLOGY, Issue 3 2004M. ELSBETH McPHEE This increased variation can translate into decreased survivorship upon reintroduction to native habitats. Data show that captive populations of oldfield mice (Peromyscus polionotus subgriseus) exhibit such an increase in variation. Motivated by these results, we developed a series of calculations for a "release ratio" that can be used to determine the number of captive-bred animals needed to compensate for the increased variance. We present calculations of release ratios for behavioral and morphological variables with different distributions and illustrate the functional relationship between release numbers, increased variation, and change in average behavior and morphology. Our calculations indicated that the release of 130,150 captive-bred oldfield mice is equivalent to the release of 100 wildlike animals. Release ratios will vary among species, however, and perhaps among different populations of the same species and should be calculated separately for each situation. Development of the release ratio is the first rigorous effort to incorporate behavioral and morphological changes due to captivity into reintroduction planning. Release ratios will help conservation biologists ensure that the appropriate number of animals is released, thus increasing the success of reintroduction programs. Resumen:,Las poblaciones cautivas pueden exhibir mayor variación conductual que sus contrapartes silvestres como resultado del relajamiento de presiones selectivas en el ambiente de cautiverio. Esta variación incrementada puede traducirse en una disminución de la supervivencia en la reintroducción a hábitats nativos. Hay datos que muestran que poblaciones cautivas de ratones Peromyscus polionotus subgriseus exhiben tal incremento en la variación. Motivados por estos resultados, desarrollamos una serie de cálculos para un "índice de liberación" que pueda utilizarse para determinar el número de animales criados en cautiverio requerido para compensar la variación incrementada. Presentamos los cálculos de 2 índices de liberación para variables conductuales y morfológicas con distribuciones diferentes e ilustramos la relación funcional entre el número de liberaciones, la variación incrementada y el cambio en la conducta promedio y la morfología. Nuestros cálculos indicaron que la liberación de 130 a 150 ratones es equivalente a la liberación de 100 animales silvestres. Sin embargo, los índices de liberación varían entre especies y quizás entre poblaciones diferentes de la misma especie y deben calcularse por separado en cada situación. El desarrollo de índices de liberación es el primer esfuerzo riguroso para incorporar cambios conductuales y morfológicos debido al cautiverio en la planificación de reintroducciones. Los índices de liberación ayudarán a que los biólogos de la conservación se aseguren que el número de animales liberados es el apropiado, incrementando con ello el éxito de los programas de reintroducción. [source] Phylogenetic Reanalysis of the Saudi Gazelle and Its Implications for ConservationCONSERVATION BIOLOGY, Issue 4 2001Robert L. Hammond The Saudi gazelle ( Gazella saudiya) was endemic to the Arabian peninsula but is now considered extinct in the wild and is potentially a candidate for captive breeding and reintroduction. Using 375 base pairs of mitochondrial DNA (mtDNA) cytochrome b gene derived from museum samples collected from the wild prior to the presumed extinction of this species, we show that G. saudiya is the sister taxon of the African dorcas gazelle ( G. dorcas). Reciprocal monophyly of G. saudiya mtDNA haplotypes with G. dorcas, coupled with morphological distinctiveness, suggests that it is an evolutionarily significant unit. These data indicate that captive populations identified previously as potential sources of G. saudiya for captive breeding appear incorrectly designated and are irrelevant to the conservation of G. saudiya. The polymerase chain reaction,restriction fragment length polymorphism ( PCR-RFLP) analysis of several private collections of living gazelles in Saudi Arabia provides no evidence for the survival of G. saudiya. We recommend that field surveys be undertaken to establish whether G. saudiya is indeed extinct in the wild and that other private collections within the Arabian peninsula be screened genetically. We urge caution when captive animals of unknown provenance are used to investigate the phylogenetics of cryptic species groups. Resumen: La identificación de poblaciones taxonómicamente apropiadas de especies en peligro para programas de reproducción en cautiverio y de reintroducción es fundamental para su éxito. La Gacela Saudi (Gazella saudiya) fue endémica a la península de Arabia pero ahora está considerada como extinta en su medio y es un candidato potencial para reproducción en cautiverio y reintroducción. Utilizando 375 pares de bases de ADN mitocondrial (ADNmt) del gene citocromo b derivados de muestras de museos colectadas en el medio silvestre antes de la extinción de la especie, mostramos que G. saudiya es el taxón hermano de la gacela dorcas africana (G. dorcas). La monofilia recíproca de haplotipos de ADNmt de G. saudiya con G. dorcas, aunado a diferencias morfológicas, sugiere que es una unidad evolutiva significativa. Estos datos indican que las poblaciones cautivas identificadas previamente como fuente potencial de G. saudiya para reproducción en cautiverio están incorrectamente identificadas y son irrelevantes para la conservación de G. saudiya. El análisis PCR-RFLP de varias colecciones privadas de gacelas vivas en Arabia Saudita no proporcionan evidencia para la supervivencia de G. saudiya. Recomendamos que se realicen muestreos en el campo para establecer si en efecto G. saudiya está extinta en su hábitat y que se examinen genéticamente las otras colecciones privadas en la península Arábiga. Recomendamos precaución cuando animales cautivos de origen desconocido son utilizados para investigar la filogenia de grupos de especies crípticas. [source] Palatal tremor in childhood: clinical and therapeutic considerationsDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 12 2006J Campistol-Plana PhD Palatal tremor (PT) is a rhythmic movement of the soft palate that often causes an ear click. PT can be symptomatic (SPT) or essential (EPT). The symptomatic form usually occurs in adults and the essential form mainly occurs in children. Several different treatments for EPT in children appear in the literature with variable reported efficacy. This report details four paediatric patients with EPT (three males, one female; mean age 6y 4mo [SD 6mo]; age at onset 6,7y) treated with piracetam (2-oxo-1-pyrrolidine acetamide). Piracetam was used to treat EPT because of its antimyoclonic properties. All children showed a good response to doses of 100 to 300mg/kg/day. EPT relapsed on withdrawal of piracetam and remitted on reintroduction. Piracetam's effect on EPT was sustained. It is concluded that piracetam is an effective drug for the treatment of EPT in children. [source] Sensitivity to sulphonylureas in patients with hepatocyte nuclear factor-1, gene mutations: evidence for pharmacogenetics in diabetesDIABETIC MEDICINE, Issue 7 2000E. R. Pearson SUMMARY Introduction Maturity-onset diabetes of the young (MODY) is characterized by autosomal dominantly inherited, early-onset, non-insulin-dependent diabetes. Mutations in the hepatocyte nuclear factor (HNF)-1, gene are the commonest cause of MODY. Individual patients with HNF-1, mutations have been reported as being unusually sensitive to the hypoglycaemic effects of sulphonylurea therapy. We report three patients, attending a single clinic, with HNF-1, mutations that show marked hypersensitivity to sulphonylureas. Case reports In cases 1 and 2 there were marked changes in HbA1c on cessation (4.4% and 5.8%, respectively) and reintroduction (5.0% and 2.6%) of sulphonylureas. Case 3 had severe hypoglycaemic symptoms on the introduction of sulphonylureas despite poor glycaemic control and was shown with a test dose of 2.5 mg glibenclamide to have symptomatic hypoglycaemia (blood glucose 2 mmol/l) after 4 h despite eating. Conclusions HNF-1, MODY diabetic subjects are more sensitive to sulphonylureas than Type 2 diabetic subjects and this is seen in different families, with different mutations and may continue up to 13 years from diagnosis. This is an example of pharmacogenetics, with the underlying aetiological genetic defect altering the pharmacological response to treatment. The present cases suggest that in HNF-1, MODY patients: (i) sulphonylureas can dramatically improve glycaemic control and should be considered as initial treatment for patients with poor glycaemic control on an appropriate diet; (ii) hypoglycaemia may complicate the introduction of sulphonylureas and therefore very low doses of short acting sulphonylureas should be used initially; and (iii) cessation of sulphonylureas should be undertaken cautiously as there may be marked deterioration in glycaemic control. Keywords, genetics, HNF-1,, MODY, pharmacogenetics, sulphonylurea sensitivity [source] Species loss leads to community closureECOLOGY LETTERS, Issue 6 2000P. Lundberg Global extinction of a species is sadly irreversible. At a local scale, however, extinctions may be followed by re-invasion. We here show that this is not necessarily the case and that an ecological community may close its doors for re-invasion of species lost from it. Previous studies of how communities are assembled have shown that there may be rules for that process and that limitations are set to the order by which species are introduced and put together. Instead of focusing on the assembly process we randomly generated simple competitive model communities that were stable and allowed for two to 10 coexisting species. When a randomly selected single species was removed from the community, the cascading species loss was recorded and frequently the resulting community was more than halved. Cascading extinctions have previously been recorded, but we here show that the relative magnitude of the cascade is dependent on community size (and not only trophic structure) and that the reintroduction of the original species lost often is impossible. Hence, species loss does not simply leave a void potentially refilled, but permanently alters the entire community structure and consequently the adaptive landscape for potential re-invaders. [source] Eradication of the invasive Pseudorasbora parva results in increased growth and production of native fishesECOLOGY OF FRESHWATER FISH, Issue 1 2009J. R. Britton Abstract,,, The topmouth gudgeon, Pseudorasbora parva, has been described as Europe's most invasive fish. To control their UK invasion, some lentic populations at risk of causing fluvial dispersal have been eradicated. The first of these operations was from a lake in north-west UK in March 2005 using rotenone application; prior to eradication, their mean density was estimated as 6.1 m,2 whereas since eradication, no P. parva have been recorded. Prior to rotenone application, the majority of native fishes were removed, held off-site and reintroduced following degradation of rotenone to safe levels. In the three growth seasons since their reintroduction and P. parva eradication, the abundance, somatic growth rate and production of roach Rutilus rutilus and common bream Abramis brama have increased significantly; production is now driven by a lower number of comparatively larger, faster growing individuals. These data suggest that the eradication of this P. parva population has been highly beneficial for the growth, recruitment and production of these native species. [source] An estrogen receptor , suppressor, microRNA-22, is downregulated in estrogen receptor ,-positive human breast cancer cell lines and clinical samplesFEBS JOURNAL, Issue 7 2010Jianhua Xiong Previous studies have suggested that microRNAs (miRNAs) may play important roles in tumorigenesis, but little is known about the functions of most miRNAs in cancer development. In the present study, we set up a cell-based screen using a luciferase reporter plasmid carrying the whole , 4.7 kb 3,-UTR of estrogen receptor , (ER,) mRNA cotransfected with a synthetic miRNA expression library to identify potential ER,-targeting miRNAs. Among all the miRNAs, miR-22 was found to repress robustly the luciferase signal in both HEK-293T and ER,-positive MCF-7 cells. Mutation of the target site was found to abrogate this repression effect of miR-22, whereas antagonism of endogenous miR-22 in MDA-MB-231 cells resulted in elevated reporter signals. We assessed the miR-22 expression patterns in five breast cancer cell lines and 23 clinical biopsies and revealed that there is a significant inverse association between the miR-22 levels and ER, protein expression. To evaluate the potential of miR-22 as a potential therapeutic intervention, we found that reduction of endogenous ER, protein levels and suppression of cancer cell growth could be achieved in MCF-7 cells by miR-22 overexpression in a way that can be recapitulated by the introduction of specific small interfering RNA against ER,. The phenomena can be rescued by the reintroduction of ER,. Taken together, our data indicate that miR-22 was frequently downregulated in ER,-positive human breast cancer cell lines and clinical samples. Direct involvement in the regulation of ER, may be one of the mechanisms through which miR-22 could play a pivotal role in the pathogenesis of breast cancer. [source] Phosphorus-limited growth dynamics in two Baltic Sea cyanobacteria, Nodularia sp. and Aphanizomenon sp.FEMS MICROBIOLOGY ECOLOGY, Issue 3 2006Jenny Degerholm Abstract Rates of carbon (C) specific growth and nitrogen (N2) fixation were monitored in cultures of Baltic Sea Nodularia and Aphanizomenon exposed to gradual limitation by inorganic phosphorus (P). Both cyanobacteria responded by decreased cellular P content followed by lowered rates of growth and N2 fixation. C-specific growth and cellular N content changed faster in Aphanizomenon both when inorganic P was lowered as well as during reintroduction of P. Aphanizomenon also showed a more rapid increase in N-specific N2 fixation associated with increased C-specific growth. When ambient concentrations of inorganic P declined, both cyanobacteria displayed higher rates of alkaline phosphatase (APase) activity. Lower substrate half-saturation constants (KM) and higher Vmax : KM ratio of the APase enzyme associated with Nodularia suggest a higher affinity for dissolved organic P (DOP) substrate than Aphanizomenon. Aphanizomenon, which appears more sensitive to changes in ambient dissolved inorganic P, may be adapted to environments with elevated concentrations of P or repeated intrusions of nutrient-rich water. Nodularia on the other hand, with its higher tolerance to increased P starvation may have an ecological advantage in stratified surface waters of the Baltic Sea during periods of low P availability. [source] Carbofuran degradation mediated by three related plasmid systemsFEMS MICROBIOLOGY ECOLOGY, Issue 3 2000A.V. Ogram Abstract Two carbofuran-metabolizing Sphingomonas strains, TA and CD, were isolated from soils with differing histories of exposure to carbofuran. These strains were compared with a previously described strain, Sphingomonas sp. CFO6, with regard to growth rate, formation of metabolites, and plasmid content and structure. Extensive regions of similarity were observed between the three different plasmid systems as evidenced by cross hybridization. In addition, all three systems harbor IS1412, an insertion sequence (IS) element involved in heat-induced loss of carbofuran phenotype in CFO6, and heat-induced carbofuran deficient mutants of all three strains correlated with loss of IS1412. A carbofuran deficient mutant of TA generated by induction of IS elements was complemented by reintroduction of the wild-type plasmid, confirming the presence of genes required for carbofuran metabolism on this plasmid. Carbofuran metabolism in these three strains is clearly linked via plasmids of different numbers and sizes that share extensive common regions, and carbofuran-degrading genes may be associated with active IS elements. [source] Inactivation of the cystatin E/M tumor suppressor gene in cervical cancerGENES, CHROMOSOMES AND CANCER, Issue 9 2008Mysore S. Veena We have previously localized a cervical cancer tumor suppressor gene to a 300 kb interval of 11q13. Analysis of candidate genes revealed loss of expression of cystatin E/M, a lysosomal cysteine protease inhibitor, in 6 cervical cancer cell lines and 9 of 11 primary cervical tumors. Examination of the three exons in four cervical cancer cell lines, 19 primary tumors, and 21 normal controls revealed homozygous deletion of exon 1 sequences in one tumor. Point mutations were observed in six other tumors. Two tumors contained mutations at the consensus binding sites for cathepsin L, a lysosomal protease overexpressed in cervical cancer. Introduction of these two point mutations using site directed mutagenesis resulted in reduced binding of mutated cystatin E/M to cathepsin L. Although mutations were not observed in any cell lines, four cell lines and 12 of 18 tumors contained promoter hypermethylation. Reexpression of cystatin E/M was observed after 5,aza 2-deoxycytidiene and/or Trichostatin A treatment of cervical cancer cell lines, HeLa and SiHa, confirming promoter hypermethylation. Ectopic expression of cystatin E/M in these two cell lines resulted in growth suppression. There was also suppression of soft agar colony formation by HeLa cells expressing the cystatin E/M gene. Reexpression of cystatin E/M resulted in decreased intracellular and extracellular expression of cathepsin L. Overexpression of cathepsin L resulted in increased cell growth which was inhibited by the reintroduction of cystatin E/M. We conclude, therefore, that cystatin E/M is a cervical cancer suppressor gene and that the gene is inactivated by somatic mutations and promoter hypermethylation. © 2008 Wiley-Liss, Inc. [source] LIVESTOCK VERSUS "WILD BEASTS": CONTRADICTIONS IN THE NATURAL PATRIMONIALIZATION OF THE PYRENEESGEOGRAPHICAL REVIEW, Issue 4 2009ISMAEL VACCARO ABSTRACT. The Pyrenees are becoming an environmental reservoir. The acute human depopulation experienced during the twentieth century and the progressive appropriation of large parts of the mountainous territory by the state in order to implement conservation policies have resulted in the return, via reintroduction or natural regeneration, of bears, wolves, beavers, river otters, marmots, mouflon, feral goats, and deer, among other species. This development, however, has not occurred without social and scientific controversy and leads to questions about territorialization and governmentality. Herders perceive wild animals as unregulated public property subsidized by the work of the local populace. Agriculturalists see their fields trespassed on a daily basis by animals they cannot kill because of their protected status. Ranchers, under extremely strict sanitation regulations, see their animals coming into contact with these unchecked wild populations. The work and living space of the mountain communities has fallen under the jurisdiction of external institutions and constituencies that value conservation and ecotourism above local subsistence. [source] Explaining trends in concentration of healthcare commissioning in the English NHSHEALTH ECONOMICS, Issue 8 2008Mark Dusheiko Abstract In recent years there have been marked changes in organisational structures and budgetary arrangements in the English National Health Service, potentially altering the relationships between purchasers (primary care organisations (PCOs) and general practices) and hospitals. We show that elective admissions from PCOs and practices became significantly more concentrated across hospitals between 1997/98 and 2002/03. There was a reduction in the average number of hospitals used by PCOs (16.7,14.2), an increase in the average share of admissions accounted for by the main hospital (49,69%), and an increase in the average Herfindahl index (0.35,0.55). About half the increase in concentration arose from the increase in the number of purchasing organisations as 100 health authorities were replaced by 303 primary care trusts. Most of the remainder was probably due to hospital mergers. Fundholding general practices that held budgets for elective admissions had less concentrated admission patterns than non-fundholders whose admissions were paid for by their PCO. Around 1/10th of the increase in concentration at practice level was due to the abolition of fundholding in April 1999. Our results have implications for the effects of the recent reintroduction of fundholding and the halving of the number of PCOs. Copyright © 2007 John Wiley & Sons, Ltd. [source] Lopinavir/ritonavir monotherapy as maintenance treatment in HIV-infected individuals with virological suppression: results from a pilot study in BrazilHIV MEDICINE, Issue 5 2008E Sprinz Objective The aim of the study was to evaluate the possibility of using lopinavir/ritonavir (LPV/RTV) alone as maintenance therapy in HIV-infected individuals with virological suppression. Design This was a single-armed single-centre pilot trial. Methods Asymptomatic HIV-infected patients on highly active antiretroviral therapy (HAART) including LPV/RTV, and with plasma HIV RNA <40 copies/mL for at least 6 months, were enrolled in the study, during which they continued with LPV/RTV alone. The intention was to recruit 25 patients to be followed for 2 years. Viral failure was defined as two consecutive HIV RNA measurements >40 copies/mL. Nadir and baseline CD4 cell counts, highest ever HIV RNA load, time with undetectable viraemia before monotherapy, number of previous antiretroviral (ARV) regimens, and gene polymorphism at CYP3A4 and CYP3A5 were evaluated. Results All patients (27) completed the study. Their median age was 43 years, and 66% were men. Ten patients (37%) failed to maintain virological suppression (the median time to HIV rebound was 10.5 months, with a range of 4,23 months). One patient developed full resistance to LPV and another developed neurocognitive impairment while on LPV/RTV which improved after HAART reintroduction. There were no differences between failures and nonfailures according to the analysed parameters. Patients with viral failure were successfully resuppressed. Conclusions LPV/RTV maintenance therapy was associated with 37% failure, a higher than expected failure rate. In order to ensure that unnecessary risks are not being taken in patients on LPV/RTV, this finding should be further evaluated in large randomized trials for longer periods of follow-up. [source] A uniform nodal strain tetrahedron with isochoric stabilizationINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 4 2009M. W. Gee Abstract A stabilized node-based uniform strain tetrahedral element is presented and analyzed for finite deformation elasticity. The element is based on linear interpolation of a classical displacement-based tetrahedral element formulation but applies nodal averaging of the deformation gradient to improve mechanical behavior, especially in the regime of near-incompressibility where classical linear tetrahedral elements perform very poorly. This uniform strain approach adopted here exhibits spurious modes as has been previously reported in the literature. We present a new type of stabilization exploiting the circumstance that the instability in the formulation is related to the isochoric strain energy contribution only and we therefore present a stabilization based on an isochoric,volumetric splitting of the stress tensor. We demonstrate that by stabilizing the isochoric energy contributions only, reintroduction of volumetric locking through the stabilization can be avoided. The isochoric,volumetric splitting can be applied for all types of materials with only minor restrictions and leads to a formulation that demonstrates impressive performance in examples provided. Copyright © 2008 John Wiley & Sons, Ltd. [source] Flying an amphibian flagship: conservation of the Axolotl Ambystoma mexicanum through nature tourism at Lake Xochimilco, MexicoINTERNATIONAL ZOO YEARBOOK, Issue 1 2008I. G. BRIDE The effectiveness of flagship species as a conservation tool is controversial, and amphibians are not usually regarded as meeting the strategic criteria that flagships demand. Capitalizing on the historical, cultural and economic importance of the Axolotl Ambystoma mexicanum at Lake Xochimilco, Mexico, a conservation programme for this species and its habitat was developed using the Axolotl as a flagship. The threats to the lake are complex and stem from the unsustainable use of its resources. The needs and livelihoods of local stakeholders must therefore be taken into account before attempting to address the threats. The programme therefore focused on developing nature tourism by training local boatmen (remeros) in environmental interpretation. Surveys showed that the boatmen increased their incomes and job satisfaction after training, and that the environmental interpretation programme improved relevant knowledge and awareness of visitors. Although ongoing threats mean that reintroduction of captive-bred Axolotls is not appropriate, zoos with captive populations of Axolotls supported the programme regionally and internationally by providing publicity, funds, staff expertise, training support and themed educational activities. By raising both funds and awareness for the wider conservation of Lake Xochimilco, the Axolotl is probably the first amphibian flagship to be launched successfully. [source] Rhinoceros behaviour: implications for captive management and conservationINTERNATIONAL ZOO YEARBOOK, Issue 1 2006M. HUTCHINS All species of rhinoceros are, to varying degrees, threatened with extinction because of poaching, habitat loss, human-rhinoceros conflict, hunting and civil unrest. Clearly the threats facing the five remaining species (Black rhinoceros Diceros bicornis, White rhinoceros Ceratotherium simum, Greater one-horned rhinoceros Rhinoceros unicornis, Javan rhinoceros Rhinoceros sondaicus and Sumatran rhinoceros Dicerorhinus sumatrensis) are anthropogenic. Although many disciplines are important for conservation, understanding the behaviour characteristics of a species should be considered a key component when developing wildlife-management and conservation strategies. A general overview of the behaviour of rhinoceros is presented, addressing ecology and social organization, activity and habitat use, feeding strategies, courtship and reproduction, and anti-predator behaviour. The implications of behavioural studies for successful management and husbandry of rhinoceros in captivity are discussed in sections on group size and composition, enclosure design and enrichment programmes, activity patterns, introductions, reproduction, hand-rearing, and health and stress. Finally, there is some discussion about the implications of this knowledge for in situ conservation in relation to designing protected areas, further aspects of animal health and stress, and reintroduction and translocation. A detailed understanding of rhinoceros behaviour is important for survival both in range-country protected areas and captivity, and such knowledge should be used to provide the most appropriate animal care and environments for these species. [source] Management of the Double-eyed or Red-browed fig parrot Cyclopsitta diophthalma macleayana at Currumbin Sanctuary, QueenslandINTERNATIONAL ZOO YEARBOOK, Issue 1 2000L. ROMER The Double-eyed fig parrot Cyclopsitta diophthalma has three subspecies in Australia which occur in isolated populations. Since 1987 Currumbin Sanctuary has been involved in a breeding programme for the Red-browed fig parrot Cyclopsitta diophthalma macleayana, to develop techniques which might be applied for the management of the highly threatened Coxen's fig parrot Cyclopsitta diophthalma coxeni should the subspecies come into captivity in the future. The aim of the programme is primarily to produce parent-reared offspring, which would be most suited to reintroduction, but the work also involves egg-fostering trials and cross-fostering of chicks. The results of the breeding programme, the problems encountered and additional conservation work carried out by Currumbin Sanctuary are described. [source] Conservation strategy maps: a tool to facilitate biodiversity action planning illustrated using the heath fritillary butterflyJOURNAL OF APPLIED ECOLOGY, Issue 2 2003G. J. Holloway Summary 1.,The UK Biodiversity Action Plan (UKBAP) identifies invertebrate species in danger of national extinction. For many of these species, targets for recovery specify the number of populations that should exist by a specific future date but offer no procedure to plan strategically to achieve the target for any species. 2.,Here we describe techniques based upon geographic information systems (GIS) that produce conservation strategy maps (CSM) to assist with achieving recovery targets based on all available and relevant information. 3.,The heath fritillary Mellicta athalia is a UKBAP species used here to illustrate the use of CSM. A phase 1 habitat survey was used to identify habitat polygons across the county of Kent, UK. These were systematically filtered using relevant habitat, botanical and autecological data to identify seven types of polygon, including those with extant colonies or in the vicinity of extant colonies, areas managed for conservation but without colonies, and polygons that had the appropriate habitat structure and may therefore be suitable for reintroduction. 4.,Five clusters of polygons of interest were found across the study area. The CSM of two of them are illustrated here: the Blean Wood complex, which contains the existing colonies of heath fritillary in Kent, and the Orlestone Forest complex, which offers opportunities for reintroduction. 5.,Synthesis and applications. Although the CSM concept is illustrated here for the UK, we suggest that CSM could be part of species conservation programmes throughout the world. CSM are dynamic and should be stored in electronic format, preferably on the world-wide web, so that they can be easily viewed and updated. CSM can be used to illustrate opportunities and to develop strategies with scientists and non-scientists, enabling the engagement of all communities in a conservation programme. CSM for different years can be presented to illustrate the progress of a plan or to provide continuous feedback on how a field scenario develops. [source] Assessing the suitability of central European landscapes for the reintroduction of Eurasian lynxJOURNAL OF APPLIED ECOLOGY, Issue 2 2002Stephanie Schadt Summary 1After an absence of almost 100 years, the Eurasian lynx Lynx lynx is slowly recovering in Germany along the German,Czech border. Additionally, many reintroduction schemes have been discussed, albeit controversially, for various locations. We present a habitat suitability model for lynx in Germany as a basis for further management and conservation efforts aimed at recolonization and population development. 2We developed a statistical habitat model using logistic regression to quantify the factors that describe lynx home ranges in a fragmented landscape. As no data were available for lynx distribution in Germany, we used data from the Swiss Jura Mountains for model development and validated the habitat model with telemetry data from the Czech Republic and Slovenia. We derived several variables describing land use and fragmentation, also introducing variables that described the connectivity of forested and non-forested semi-natural areas on a larger scale than the map resolution. 3We obtained a model with only one significant variable that described the connectivity of forested and non-forested semi-natural areas on a scale of about 80 km2. This result is biologically meaningful, reflecting the absence of intensive human land use on the scale of an average female lynx home range. Model testing at a cut-off level of P > 0·5 correctly classified more than 80% of the Czech and Slovenian telemetry location data of resident lynx. Application of the model to Germany showed that the most suitable habitats for lynx were large-forested low mountain ranges and the large forests in east Germany. 4Our approach illustrates how information on habitat fragmentation on a large scale can be linked with local data to the potential benefit of lynx conservation in central Europe. Spatially explicit models like ours can form the basis for further assessing the population viability of species of conservation concern in suitable patches. [source] Immediate acid-suppressing effects of ranitidine hydrochloride and rabeprazole sodium following initial administration and reintroduction: A randomized, cross-over study using wireless pH monitoring capsulesJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 4 2009Shouko Ono Abstract Background and Aim:, Histamine 2 receptor antagonists and proton-pump inhibitors, drugs that are widely used for the treatment of acid-related diseases, have different clinical characteristics. The objective of this study was to compare the acid-suppressing effects of ranitidine hydrochloride and those of rabeprazole sodium at the first administration and re-administration after withdrawal. Methods:, The study was designed as an open-label, randomized, two-way cross-over trial. Seven Helicobacter pylori -negative healthy volunteers were enrolled in this study. Ranitidine hydrochloride (300 mg/day) or rabeprazole sodium (20 mg/day) was administered from days 1 to 7 and from days 11 to 13. The percentage of time with gastric pH < 4 and the median gastric pH were evaluated for 15 consecutive days by a Bravo capsule fixed to the stomach. Results:, On day 1, there was no significant difference between the acid-suppressing effects of the two drugs (ranitidine vs rabeprazole: not significant). Although rabeprazole sodium maintained a potent and stable effect from days 2 to 7 (ranitidine vs rabeprazole: P < 0.05), the effect of ranitidine hydrochloride was attenuated after day 4. In addition, the effect of ranitidine hydrochloride at re-administration was attenuated (days 11, 12, and 13 vs pre-administration: not significant). Conclusion:, In view of our observations, we expect symptoms associated with gastric acidity to be more adequately controlled with rabeprazole sodium in the short term when compared to ranitidine hydrochloride. [source] Clinical audit of the effects of low-fibre diet on irritable bowel syndromeJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 4 2000J. T. Woolner Introduction High-fibre diets are frequently advocated for the treatment of irritable bowel syndrome (IBS) although there is little scientific evidence to support this. Experience of patients on low-fibre diets suggests that this may be an effective treatment for IBS, warranting investigation. Methods Symptoms were recorded for 204 IBS patients presenting in the gastroenterology clinic. They were then advised on a low-fibre diet with bulking agents as appropriate. Symptoms were reassessed by postal questionnaire 4 weeks later. Patients who had improved on the diet were advised on the gradual reintroduction of different types of fibre to determine the quantity and type of fibre tolerated by the individual. Results Seventy-four per cent of questionnaires were returned. A significant improvement (60,100% improvement in overall well-being) was recorded by 49% of patients. Conclusion This preliminary study suggests that low-fibre diets may be an effective treatment for some IBS patients and justifies further investigation as a full clinical trial. [source] Favorable outcome of ex-vivo purging of monocytes after the reintroduction of treatment after interruption in patients infected with multidrug resistant HIV-1,JOURNAL OF MEDICAL VIROLOGY, Issue 11 2007Hamid Hasson Abstract In multidrug resistant patients treatment interruptions allow the selection of archived wild-type drug-susceptible viruses that compete for the less fit drug-resistant strains. However, the selection of viruses with increased replicative capacity is often followed by a loss of CD4+ T cells. In addition, drug resistant variants later re-emerge limiting the overall clinical benefit of treatment interruption. Blood monocytes are a key component of the HIV reservoir and can be partially removed by a system for purging of myeloid cells (MYP). This study tested the safety and efficacy of MYP on multidrug resistant patients who underwent treatment interruption. Twelve patients were randomized to receive or not six cycles of MYP during treatment interruption. An optimized antiretroviral regimen was reintroduced after the reappearance of a drug susceptible genotype. Following therapy reintroduction, a long lasting increase in CD4+ T cell counts was observed only in the treatment interruption,+,MYP patients but not in the control patients. Five/six treatment interruption,+,MYP patients never experienced virological rebound during a median follow up period of 98 weeks. In contrast, 4/6 patients who did not receive MYP never reached complete viral suppression and had a virological rebound after a median of 16.5 weeks after treatment reintroduction. The difference between the two groups in the time to virological rebound was statistically significant (P,=,0.021). A consistent decrease of HIV DNA load in CD14+ purified cells was observed only in treatment interruption,+,MYP patients. These data suggest that MYP can improve the immunological and virological response to treatment interruption. J. Med. Virol. 79:1640,1649, 2007. © 2007 Wiley-Liss, Inc. [source] New evidence for the occurrence of Eurasian lynx (Lynx lynx) in medieval Britain,JOURNAL OF QUATERNARY SCIENCE, Issue 1 2006David A. Hetherington Abstract The presence of Eurasian lynx as a former native species in Britain during the Holocene is known from bones recovered from several sites. AMS radiocarbon dating of lynx bone recovered from two sites in the Craven area of northern England gave 1842,±,35 14C,yr,BP and 1550,±,24 14C,yr,BP, together representing the youngest dates for lynx from England, and in the case of the latter, the youngest for Britain as a whole. These dates support the view that the game animal whose occurrence in the nearby Lake District is described in the early 7th century Cumbric text Pais Dinogad, and whose translation to date has been problematic, is a lynx. The occurrence of lynx in early medieval Britain shows that earlier periods of climate change, previously blamed for the species' extinction in Britain, were not responsible. Instead, anthropogenic factors such as severe deforestation, declining deer populations, and persecution, are likely to have caused the extirpation of lynx in Britain. Consequently, the lynx qualifies as a candidate for reintroduction. Large-scale reafforestation, the growth of deer populations, and more positive attitudes towards carnivores in modern society, could permit the restoration of lynx to Britain, particularly in Scotland. Copyright © 2005 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||||||||