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1.
PLoS One ; 16(12): e0258714, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34962925

RESUMEN

This study evaluates the diversity of the so-called 'Moroccan Royal lions' using genealogical information. Lions are no longer extant in North Africa, but the previous wild population was an important element of the now-recognised northern subspecies (Panthera leo leo) that ranged across West Africa, North Africa and the Middle East into India. The remaining captive population of 'Moroccan Royal lions' seems to be significantly endangered by the loss of diversity due to the effective population size decrease. The pedigree file of this captive lion population consisted of 454 individuals, while the reference population included 98 animals (47 males and 51 females). The completeness of the pedigree data significantly decreased with an increasing number of generations. The highest percentage of pedigree completeness (over 70%) was achieved in the first generation of the reference population. Pedigree-based parameters derived from the common ancestor and gene origin were used to estimate the state of diversity. In the reference population, the average inbreeding coefficient was 2.14%, while the individual increase in inbreeding over generations was 2.31%. Overall, the reference population showed lower average inbreeding and average relatedness compared with the pedigree file. The number of founders (47), the effective number of founders (24) and the effective number of ancestors (22) were estimated in the reference population. The effective population size of 14.02 individuals confirms the critically endangered status of the population and rapid loss of diversity in the future. Thus, continuous monitoring of the genetic diversity of the 'Moroccan Royal lion' group is required, especially for long-term conservation management purposes, as it would be an important captive group should further DNA studies establish an affinity to P. leo leo.


Asunto(s)
Conservación de los Recursos Naturales , Variación Genética , Leones/genética , Animales , Femenino , Genética de Población , Masculino , Marruecos , Linaje , Análisis de Componente Principal , Probabilidad
2.
Sci Rep ; 11(1): 4469, 2021 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-33627691

RESUMEN

Reintroduction of endangered species is an effective and increasingly important conservation strategy once threats have been addressed. The greater one-horned rhinoceros and swamp buffalo have declined through historic hunting and habitat loss. We identify and evaluate available habitat across their historic range (India, Nepal, and Bhutan) for reintroducing viable populations. We used Species Distribution Models in Maxent to identify potential habitats and evaluated model-identified sites through field visits, interviews of wildlife managers, literature, and population-habitat viability analysis. We prioritize sites based on size, quality, protection, management effectiveness, biotic pressures, and potential of conflict with communities. Our results suggest that populations greater than 50 for rhinoceros and 100 for buffalo were less susceptible to extinction, and could withstand some poaching, especially if supplemented or managed as a metapopulation. We note some reluctance by managers to reintroduce rhinoceros due to high costs associated with subsequent protection. Our analysis subsequently prioritised Corbett and Valmiki, for rhino reintroduction and transboundary complexes of Chitwan-Parsa-Valmiki and Dudhwa-Pilibhit-Shuklaphanta-Bardia for buffalo reintroductions. Establishing new safety-nets and supplementing existing populations of these megaherbivores would ensure their continued survival and harness their beneficial effect on ecosystems and conspecifics like pygmy hog, hispid hare, swamp deer, hog deer, and Bengal florican.

3.
Rheumatology (Oxford) ; 59(9): 2625-2636, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32365362

RESUMEN

OBJECTIVES: Cytokines released by infiltrating T cells may promote mechanisms leading to fibrosis in scleroderma. The aim of this study was to investigate the role of the Th2 cytokine IL-31, and its receptor IL-31RA, in scleroderma skin and lung fibrosis. METHODS: IL-31 was measured by ELISA of plasma, and by immunochemistry of fibrotic skin and lung tissue of scleroderma patients. The receptor, IL-31RA, was assayed by qPCR of tissue resident cells. Next-generation sequencing was used to profile the responses of normal skin fibroblasts to IL-31. In wild-type Balb/c mice, IL-31 was administered by subcutaneous mini pump, with or without additional TGFß, and the fibrotic reaction measured by histology and ELISA of plasma. RESULTS: IL-31 was present at high levels in plasma and fibrotic skin and lung lesions in a subset of scleroderma patients, and the receptor overexpressed by downstream cells relevant to the disease process, including skin and lung fibroblasts, through loss of epigenetic regulation by miR326. In skin fibroblasts, IL-31 induced next generation sequencing profiles associated with cellular growth and proliferation, anaerobic metabolism and mineralization, and negatively associated with angiogenesis and vascular repair, as well as promoting phenotype changes including migration and collagen protein release via pSTAT3, resembling the activation state in the disease. In mice, IL-31 induced skin and lung fibrosis. No synergy was seen with TGFß, which supressed IL-31RA. CONCLUSION: IL-31/IL-31RA is confirmed as a candidate pro-fibrotic pathway, which may contribute to skin and lung fibrosis in a subset of scleroderma patients.


Asunto(s)
Interleucinas/inmunología , Pulmón , Receptores de Interleucina/inmunología , Esclerodermia Sistémica , Piel , Animales , Epigénesis Genética/inmunología , Fibroblastos/metabolismo , Fibrosis/inmunología , Humanos , Pulmón/inmunología , Pulmón/patología , Ratones , Ratones Endogámicos BALB C , Esclerodermia Sistémica/inmunología , Esclerodermia Sistémica/patología , Piel/inmunología
4.
J Pharm Sci ; 109(4): 1509-1518, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31884015

RESUMEN

Cediranib maleate is an active pharmaceutical ingredient (API) in phase III of development within AstraZeneca's oncology portfolio. Analysis of the crystal structure of this API confirmed that the selected salt form was robust. The salt formation step had to be redesigned to avoid an unwanted metastable polymorph. A solvate with a twist appeared during later development and was avoided using insights gained from its crystal structure. Differences between predicted and experimental aspect ratios correlate with weaker crystal interactions. Acceptable variability in particle size was defined and accommodated. The "Matwall" is introduced as a tool for building control of API performance from the crystal structure upward.


Asunto(s)
Preparaciones Farmacéuticas , Cristalización , Maleatos , Tamaño de la Partícula , Quinazolinas
5.
J Pharm Sci ; 108(5): 1655-1662, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30615878

RESUMEN

We report the generation and statistical analysis of the CSD drug subset: a subset of the Cambridge Structural Database (CSD) consisting of every published small-molecule crystal structure containing an approved drug molecule. By making use of InChI matching, a CSD Python API workflow to link CSD entries to the online database Drugbank.ca has been produced. This has resulted in a subset of 8632 crystal structures, representing all published solid forms of 785 unique drug molecules. We hope that this new resource will lead to improvements in targeted cheminformatics and statistical model building in a pharmaceutical setting. In addition to this, as part of the Advanced Digital Design of Pharmaceutical Therapeutics collaboration between academia and industry, we have been given the unique opportunity to run comparative analysis on the internal crystal structure databases of AstraZeneca and Pfizer, alongside comparison to the CSD as a whole.


Asunto(s)
Preparaciones Farmacéuticas/química , Bibliotecas de Moléculas Pequeñas/química , Cristalografía por Rayos X/métodos , Bases de Datos Factuales , Bases de Datos Farmacéuticas , Diseño de Fármacos
6.
Conserv Biol ; 32(2): 366-375, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28856725

RESUMEN

Conservation requires successful outcomes. However, success is perceived in many different ways depending on the desired outcome. Through a questionnaire survey, we examined perceptions of success among 355 scientists and practitioners working on amphibian conservation from over 150 organizations in more than 50 countries. We also sought to identify how different types of conservation actions and respondent experience and background influenced perceptions. Respondents identified 4 types of success: species and habitat improvements (84% of respondents); effective program management (36%); outreach initiatives such as education and public engagement (25%); and the application of science-based conservation (15%). The most significant factor influencing overall perceived success was reducing threats. Capacity building was rated least important. Perceptions were influenced by experience, professional affiliation, involvement in conservation practice, and country of residence. More experienced practitioners associated success with improvements to species and habitats and less so with education and engagement initiatives. Although science-based conservation was rated as important, this factor declined in importance as the number of programs a respondent participated in increased, particularly among those from less economically developed countries. The ultimate measure of conservation success-population recovery-may be difficult to measure in many amphibians; difficult to relate to the conservation actions intended to drive it; and difficult to achieve within conventional funding time frames. The relaunched Amphibian Conservation Action Plan provides a framework for capturing lower level processes and outcomes, identifying gaps, and measuring progress.


Asunto(s)
Anfibios , Conservación de los Recursos Naturales , Animales , Ecosistema
7.
Int J Evol Biol ; 2016: 6901892, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27656310

RESUMEN

The lions of North Africa were unique in ecological terms as well as from a human cultural perspective and were the definitive lions of Roman and Medieval Europe. Labelled "Barbary" lions, they were once numerous in North Africa but were exterminated by the mid-20th century. Despite subsequent degeneration of the Atlas Mountain ecosystem through human pressures, the feasibility of lion reintroduction has been debated since the 1970s. Research on the long-established captive lion collection traditionally kept by the sultans and kings of Morocco has enabled selective breeding coordinated across Moroccan and European zoos involving a significant number of animals. Molecular genetic research has recently provided insights into lion phylogeny which, despite previous suggestions that all lions share recent common ancestry, now indicates clear distinctions between lions in North, West, and Central Africa, the Middle East, and India versus those in Southern and Eastern Africa. A review of the evolutionary relevance of North African lions highlights the important challenges and opportunities in understanding relationships between Moroccan lions, extinct North African lions, and extant lion populations in India and West and Central Africa and the potential role for lions in ecosystem recovery in those regions.

8.
PeerJ ; 3: e1224, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26357597

RESUMEN

As species become rare and approach extinction, purported sightings can be controversial, especially when scarce management resources are at stake. We consider the probability that each individual sighting of a series is valid. Obtaining these probabilities requires a strict framework to ensure that they are as accurately representative as possible. We used a process, which has proven to provide accurate estimates from a group of experts, to obtain probabilities for the validation of 32 sightings of the Barbary lion. We consider the scenario where experts are simply asked whether a sighting was valid, as well as asking them to score the sighting based on distinguishablity, observer competence, and verifiability. We find that asking experts to provide scores for these three aspects resulted in each sighting being considered more individually, meaning that this new questioning method provides very different estimated probabilities that a sighting is valid, which greatly affects the outcome from an extinction model. We consider linear opinion pooling and logarithm opinion pooling to combine the three scores, and also to combine opinions on each sighting. We find the two methods produce similar outcomes, allowing the user to focus on chosen features of each method, such as satisfying the marginalisation property or being externally Bayesian.

14.
PLoS One ; 8(4): e60174, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23573239

RESUMEN

Estimations of species extinction dates are rarely definitive, yet declarations of extinction or extirpation are important as they define when conservation efforts may cease. Erroneous declarations of extinctions not only destabilize conservation efforts but also corrode local community support. Mismatches in perceptions by the scientific and local communities risk undermining sensitive, but important partnerships. We examine observations relating to the decline and extinction of Barbary lions in North Africa. Whilst the extinction predates the era of the scientific conservation movement, the decline is relatively well documented in historical records. Recently unearthed accounts suggest Barbary lions survived later than previously assumed. We use probabilistic methods to estimate a more recent extinction date for the subspecies. The evidence presented for a much later persistence of lions in North Africa, including generations when sightings were nil, suggests caution when considering felid populations as extinct in the wild. The case raises the possibility that captive animals descended from the Moroccan royal collection are closer contemporaries to wild Barbary lions. Furthermore, our results highlight the vulnerability of very small lion populations and the significance of continued conservation of remnant lion populations in Central and West Africa.


Asunto(s)
Conservación de los Recursos Naturales , Extinción Biológica , Leones , Argelia , Animales , Modelos Estadísticos , Marruecos , Población , Túnez
15.
J Virol ; 86(9): 5221-9, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22345474

RESUMEN

Circoviruses are among the smallest and simplest of all viruses, but they are relatively poorly characterized. Here, we intensively sampled two sympatric parrot populations from Mauritius over a period of 11 years and screened for the circovirus Beak and feather disease virus (BFDV). During the sampling period, a severe outbreak of psittacine beak and feather disease, which is caused by BFDV, occurred in Echo parakeets. Consequently, this data set presents an ideal system for studying the evolution of a pathogen in a natural population and to understand the adaptive changes that cause outbreaks. Unexpectedly, we discovered that the outbreak was most likely caused by changes in functionally important regions of the normally conserved replication-associated protein gene and not the immunogenic capsid. Moreover, these mutations were completely fixed in the Echo parakeet host population very shortly after the outbreak. Several capsid alleles were linked to the replication-associated protein outbreak allele, suggesting that whereas the key changes occurred in the latter, the scope of the outbreak and the selective sweep may have been influenced by positive selection in the capsid. We found evidence for viral transmission between the two host populations though evidence for the invasive species as the source of the outbreak was equivocal. Finally, the high evolutionary rate that we estimated shows how rapidly new variation can arise in BFDV and is consistent with recent results from other small single-stranded DNA viruses.


Asunto(s)
Enfermedades de las Aves/virología , Infecciones por Circoviridae/veterinaria , Circovirus/genética , Brotes de Enfermedades/veterinaria , Especies en Peligro de Extinción , Evolución Molecular , Periquitos/virología , Animales , Enfermedades de las Aves/epidemiología , Enfermedades de las Aves/transmisión , Infecciones por Circoviridae/epidemiología , Infecciones por Circoviridae/transmisión , Circovirus/clasificación , Cruzamientos Genéticos , Genes Virales , Datos de Secuencia Molecular , Tasa de Mutación , Filogenia , Selección Genética
16.
Conserv Biol ; 24(6): 1448-58, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20825449

RESUMEN

The current shortfall in effectiveness within conservation biology is illustrated by increasing interest in "evidence-based conservation," whose proponents have identified the need to benchmark conservation initiatives against actions that lead to proven positive effects. The effectiveness of conservation policies, approaches, and evaluation is under increasing scrutiny, and in these areas models of excellence used in business could prove valuable. Typically, conservation programs require years of effort and involve rigorous long-term implementation processes. Successful balance of long-term efforts alongside the achievement of short-term goals is often compromised by management or budgetary constraints, a situation also common in commercial businesses. "Business excellence" is an approach many companies have used over the past 20 years to ensure continued success. Various business excellence evaluations have been promoted that include concepts that could be adapted and applied in conservation programs. We describe a conservation excellence model that shows how scientific processes and results can be aligned with financial and organizational measures of success. We applied the model to two well-documented species conservation programs. In the first, the Po'ouli program, several aspects of improvement were identified, such as more authority for decision making in the field and better integration of habitat management and population recovery processes. The second example, the black-footed ferret program, could have benefited from leadership effort to reduce bureaucracy and to encourage use of best-practice species recovery approaches. The conservation excellence model enables greater clarity in goal setting, more-effective identification of job roles within programs, better links between technical approaches and measures of biological success, and more-effective use of resources. The model could improve evaluation of a conservation program's effectiveness and may be used to compare different programs, for example during reviews of project performance by sponsoring organizations.


Asunto(s)
Conservación de los Recursos Naturales , Modelos Organizacionales , Liderazgo , Objetivos Organizacionales
17.
Br J Nurs ; 19(3): 186-93, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20220663

RESUMEN

AIM: The purpose of the study was to explore nurses' perceptions and understanding of patient-centred care (PCC) in Bhutan. BACKGROUND: Nurses' perceptions and understanding of PCC in Bhutan are unknown. METHODS: A non-probability convenience sample was taken and a mixed method (quantitative and qualitative descriptive) used. Survey questionnaires were administered to 87 Bhutanese nurses in three types of hospitals--the National Referral Hospital, the regional referral hospital and the district hospital. Descriptive statistics including frequency distribution, mean and standard deviation (SD) were used for analysis. Spearman's correlation coefficients were used to investigate relationships between demographic variables. RESULTS: The nursing labour force in Bhutan knows which behaviours are considered necessary for practising PCC. The mean (SD) rating of behaviours considered critical for practising PCC was 4.29 (0.22), five being the highest score. Bhutanese nurses described PCC, according to qualitative descriptive analysis, as being based on individual patient assessment (22/87 or 25% of respondents), using a holistic model of care (38/87 or 44%) that was based on evidence (38/87 or 44%). A higher level of education (79/87 or 91%) was found to be the main factor that would facilitate the development of PCC, while inadequate staffing, in terms of insufficient numbers of staff and lack of advanced practitioners (56/87 or 64%), was revealed as the main factor that hinders development of PCC. CONCLUSION: Bhutanese nurses believed certain behaviours were critical to PCC. Reform of higher nursing education, putting an emphasis on PCC, would improve nursing practice and increase its scope.


Asunto(s)
Actitud del Personal de Salud , Rol de la Enfermera/psicología , Personal de Enfermería en Hospital , Atención Dirigida al Paciente/organización & administración , Adulto , Análisis de Varianza , Bután , Comprensión , Países en Desarrollo , Educación Continua en Enfermería , Femenino , Conocimientos, Actitudes y Práctica en Salud , Necesidades y Demandas de Servicios de Salud , Humanos , Masculino , Persona de Mediana Edad , Modelos de Enfermería , Investigación Metodológica en Enfermería , Personal de Enfermería en Hospital/educación , Personal de Enfermería en Hospital/organización & administración , Personal de Enfermería en Hospital/psicología , Investigación Cualitativa , Estadísticas no Paramétricas , Encuestas y Cuestionarios
18.
J Pharm Sci ; 96(5): 1053-68, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17455329

RESUMEN

The preparation of molecular salts as potential delivery vehicles for pharmaceutically active compounds is more common than current appreciation of the phenomena governing the solubility and isolation of salts suggests. In addition, it would appear that there are no reported measurements on a large enough data set for a serious structure-property relationship analysis to have been performed for this class of material. This means that at present, the ability to predict which salt forms will have desirable physical properties is essentially nonexistent. The work reported here sets out to explore these issues using new data on 17 salts obtained from a screen performed on the basic pharmaceutical ephedrine. The importance of solvent choice in salt formation, of salt selection in the control of bioavailability and of ternary phase equilibria in salt isolation and the relationship between a number of measured and calculated crystal properties are illustrated and discussed. The consequences of these relations for the general design, implementation, interpretation, and scale-up of salts screens are also explored.


Asunto(s)
Ácidos/química , Portadores de Fármacos/síntesis química , Efedrina/química , Solventes/química , Tecnología Farmacéutica/métodos , Ácidos Carboxílicos/química , Química Farmacéutica , Cristalización , Ácidos Dicarboxílicos/química , Etanol/química , Concentración de Iones de Hidrógeno , Hidroxiácidos/química , Metanol/química , Modelos Químicos , Estructura Molecular , Transición de Fase , Sales (Química)/química , Solubilidad , Relación Estructura-Actividad , Ácidos Sulfónicos/química , Temperatura , Termodinámica , Agua/química
19.
Acta Crystallogr B ; 62(Pt 3): 498-505, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16710070

RESUMEN

The structures of two neutral and 17 salt forms of the base (1R, 2S)-(-)-ephedrine are reported. These structures are discussed in the light of the conformers of the ephedrine moiety, the existence of bilayers and the structure determining role of the counterions. Overall, most of the salt structures are essentially derived from the observed packing of the neutral base and are dominated by the amphiphilic nature of the ephedrine molecular structure. In a few cases the size and hydrophobicity of the counterion disrupts this behaviour.


Asunto(s)
Efedrina/química , Ácidos/química , Ácidos Carboxílicos/química , Cristalografía por Rayos X , Conformación Molecular , Sales (Química)/química , Ácidos Sulfónicos/química
20.
Am J Obstet Gynecol ; 192(1): 23-30, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15671997

RESUMEN

OBJECTIVE: Live birth rates are increased by treatment with heparin and aspirin in cases of poor pregnancy outcome such as antiphospholipid syndrome. Both drugs may attenuate miscarriage by inhibiting aberrant coagulation or by modulating trophoblast apoptosis. Here we assessed their roles in trophoblast apoptosis in vitro. STUDY DESIGN: BeWo cells and placental villi were cultured in sera from women with successful or failing in vitro fertilization, with and without heparin or aspirin. Apoptosis was assessed by using DNA laddering, cytokeratin 18 neoepitope formation, Bcl-2, and caspase 7 expression. RESULTS: In BeWo cells, sera from in vitro fertilization failure increased trophoblast apoptosis, whereas heparin and aspirin reversed these effects. In villous trophoblast, heparin increased Bcl-2 and cytokeratin 18 protein expression. Heparin and aspirin inhibited DNA laddering. CONCLUSION: Heparin and aspirin modulate trophoblast apoptosis suggesting a direct impact on trophoblast biology, thus providing an additional mechanism to explain the clinical benefits of heparin and aspirin on recurrent pregnancy loss.


Asunto(s)
Anticoagulantes/farmacología , Aspirina/farmacología , Heparina/farmacología , Enfermedades Placentarias/prevención & control , Placenta/efectos de los fármacos , Complicaciones Hematológicas del Embarazo/prevención & control , Aborto Habitual/patología , Aborto Habitual/prevención & control , Anticoagulantes/administración & dosificación , Anticoagulantes/uso terapéutico , Apoptosis , Aspirina/administración & dosificación , Aspirina/uso terapéutico , Línea Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Fertilización In Vitro , Heparina/administración & dosificación , Heparina/uso terapéutico , Humanos , Enfermedades Placentarias/patología , Embarazo , Complicaciones Hematológicas del Embarazo/patología , Trofoblastos/efectos de los fármacos
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