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1.
BMC Genomics ; 23(1): 321, 2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35459090

RESUMEN

BACKGROUND: Previous phylogeographic studies of the lion (Panthera leo) have improved our insight into the distribution of genetic variation, as well as a revised taxonomy which now recognizes a northern (Panthera leo leo) and a southern (Panthera leo melanochaita) subspecies. However, existing whole range phylogeographic studies on lions either consist of very limited numbers of samples, or are focused on mitochondrial DNA and/or a limited set of microsatellites. The geographic extent of genetic lineages and their phylogenetic relationships remain uncertain, clouded by massive sampling gaps, sex-biased dispersal and incomplete lineage sorting. RESULTS: In this study we present results of low depth whole genome sequencing and subsequent variant calling in ten lions sampled throughout the geographic range, resulting in the discovery of >150,000 Single Nucleotide Polymorphisms (SNPs). Phylogenetic analyses revealed the same basal split between northern and southern populations, as well as four population clusters on a more local scale. Further, we designed a SNP panel, including 125 autosomal and 14 mitochondrial SNPs, which was tested on >200 lions from across their range. Results allow us to assign individuals to one of these four major clades (West & Central Africa, India, East Africa, or Southern Africa) and delineate these clades in more detail. CONCLUSIONS: The results presented here, particularly the validated SNP panel, have important applications, not only for studying populations on a local geographic scale, but also for tracing samples of unknown origin for forensic purposes, and for guiding conservation management of ex situ populations. Thus, these genomic resources not only contribute to our understanding of the evolutionary history of the lion, but may also play a crucial role in conservation efforts aimed at protecting the species in its full diversity.


Asunto(s)
Leones , Panthera , Animales , Variación Genética , Humanos , Leones/genética , Panthera/genética , Filogenia , Polimorfismo de Nucleótido Simple , Secuenciación Completa del Genoma
2.
Acta Biomater ; 135: 243-259, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34509697

RESUMEN

In situ heart valve tissue engineering is an emerging approach in which resorbable, off-the-shelf available scaffolds are used to induce endogenous heart valve restoration. Such scaffolds are designed to recruit endogenous cells in vivo, which subsequently resorb polymer and produce and remodel new valvular tissue in situ. Recently, preclinical studies using electrospun supramolecular elastomeric valvular grafts have shown that this approach enables in situ regeneration of pulmonary valves with long-term functionality in vivo. However, the evolution and mechanisms of inflammation, polymer absorption and tissue regeneration are largely unknown, and adverse valve remodeling and intra- and inter-valvular variability have been reported. Therefore, the goal of the present study was to gain a mechanistic understanding of the in vivo regenerative processes by combining routine histology and immunohistochemistry, using a comprehensive sheep-specific antibody panel, with Raman microspectroscopy for the spatiotemporal analysis of in situ tissue-engineered pulmonary valves with follow-up to 24 months from a previous preclinical study in sheep. The analyses revealed a strong spatial heterogeneity in the influx of inflammatory cells, graft resorption, and foreign body giant cells. Collagen maturation occurred predominantly between 6 and 12 months after implantation, which was accompanied by a progressive switch to a more quiescent phenotype of infiltrating cells with properties of valvular interstitial cells. Variability among specimens in the extent of tissue remodeling was observed for follow-up times after 6 months. Taken together, these findings advance the understanding of key events and mechanisms in material-driven in situ heart valve tissue engineering. STATEMENT OF SIGNIFICANCE: This study describes for the first time the long-term in vivo inflammatory and regenerative processes that underly in situ heart valve tissue engineering using resorbable synthetic scaffolds. Using a unique combinatorial analysis of immunohistochemistry and Raman microspectroscopy, important spatiotemporal variability in graft resorption and tissue formation was pinpointed in in situ tissue-engineered heart valves, with a follow-up time of up to 24 months in sheep. This variability was correlated to heterogenous regional cellular repopulation, most likely instigated by region-specific differences in surrounding tissue and hemodynamics. The findings of this research contribute to the mechanistic understanding of in situ tissue engineering using resorbable synthetics, which is necessary to enable rational design of improved grafts, and ensure safe and robust clinical translation.


Asunto(s)
Estenosis de la Válvula Aórtica , Calcinosis , Prótesis Valvulares Cardíacas , Válvula Pulmonar , Implantes Absorbibles , Animales , Válvula Aórtica , Células Cultivadas , Válvulas Cardíacas , Ovinos , Ingeniería de Tejidos
3.
Anim Genet ; 52(5): 675-682, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34143521

RESUMEN

The domestic cat (Felis silvestris catus) is a valued companion animal throughout the world. Over 60 different cat breeds are accepted for competition by the cat fancy registries in different countries. Genetic markers, including short tandem repeats and SNPs, are available to evaluate and manage levels of inbreeding and genetic diversity, population and breed structure relationships, and individual identification for forensic and registration purposes. The International Society of Animal Genetics (ISAG) hosts the Applied Genetics in Companion Animals Workshop, which supports the standardization of genetic marker panels and genotyping for the identification of cats via comparison testing. SNP panels have been in development for many species, including the domestic cat. An ISAG approved core panel of SNPs for use in cat identification and parentage analyses is presented. SNPs (n = 121) were evaluated by different university-based and commercial laboratories using 20 DNA samples as part of the ISAG comparison testing procedures. Different SNP genotyping technologies were examined, including DNA arrays, genotyping-by-sequencing and mass spectroscopy, to select a robust and efficient panel of 101 SNPs as the ISAG core panel for cats. The SNPs are distributed across all chromosomes including two on the X chromosome and an XY pseudo-autosomal sexing marker (zinc-finger XY; ZFXY). A population study demonstrated that the markers have an average polymorphic information content of 0.354 and a power of exclusion greater than 0.9999. The SNP panel should keep testing affordable while also allowing for the development of additional panels to monitor health, phenotypic traits, hybrid cats and highly inbred cats.


Asunto(s)
Gatos/genética , Marcadores Genéticos , Técnicas de Genotipaje , Polimorfismo de Nucleótido Simple , Animales , Cruzamiento , Genética de Población , Técnicas de Genotipaje/normas , Análisis de Secuencia por Matrices de Oligonucleótidos/normas
4.
Internist (Berl) ; 61(7): 746-753, 2020 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-32533196

RESUMEN

A 57-year-old woman underwent esophagogastroduodenoscopy due to a continuous drop in hemoglobin levels reaching 7.4 g/dl after treatment with intravenous thrombolytic therapy 1 week earlier because of an ischemic insult. Numerous erosive lesions were found in the gastric corpus. Histological staining of a specimen from the gastric lesions revealed a poorly differentiated adenocarcinoma. Immunohistochemical examination confirmed the diagnosis of gastric metastasis from lung cancer based on positive staining for thyroid transcriptional factor­1 (TTF-1) and cytokeratin 7 (CK7) as well as via negative staining for caudal-type homeobox­2 (CDX-2). Chest computed tomography demonstrated a mediastinal mass, measuring 3.2 cm and involving the cervical and supraclavicular lymph nodes. A lymph node was subsequently extirpated. Immunohistochemical examination confirmed the diagnosis of lymph node metastasis from lung cancer by positive staining for TTF­1 and CK7. Symptomatic gastric metastasis from lung cancer is an extremely rare clinical entity. Transesophageal echocardiography detected a mass measuring 1.6 cm at the mitral valve with pericardial effusion. On the basis of the echocardiographic findings, a malignant origin was suggested after exclusion of infectious endocarditis. We assumed that the multiple organ infarctions (spleen, kidney, and brain) and gastric hematogenous metastasis must have been caused by disseminated arterial tumor embolism from the intracardiac metastasis. The patient was treated palliatively and died.


Asunto(s)
Adenocarcinoma/patología , Gastritis/patología , Hemoglobinas/efectos de los fármacos , Accidente Cerebrovascular/terapia , Terapia Trombolítica/efectos adversos , Ecocardiografía Transesofágica , Resultado Fatal , Femenino , Humanos , Persona de Mediana Edad
5.
Biol Sex Differ ; 10(1): 20, 2019 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-30992051

RESUMEN

BACKGROUND: Antarctica challenges human explorers by its extreme environment. The effects of these unique conditions on the human physiology need to be understood to best mitigate health problems in Antarctic expedition crews. Moreover, Antarctica is an adequate Earth-bound analogue for long-term space missions. To date, its effects on human physiology have been studied mainly in male cohorts though more female expeditioners and applicants in astronaut training programs are selected. Therefore, the identification of sex differences in stress and immune reactions are becoming an even more essential aim to provide a more individualized risk management. METHODS: Ten female and 16 male subjects participated in three 1-year expeditions to the German Antarctic Research Station Neumayer III. Blood, saliva, and urine samples were taken 1-2 months prior to departure, subsequently every month during their expedition, and 3-4 months after return from Antarctica. Analyses included cortisol, catecholamine and endocannabinoid measurements; psychological evaluation; differential blood count; and recall antigen- and mitogen-stimulated cytokine profiles. RESULTS: Cortisol showed significantly higher concentrations in females than males during winter whereas no enhanced psychological stress was detected in both sexes. Catecholamine excretion was higher in males than females but never showed significant increases compared to baseline. Endocannabinoids and N-acylethanolamides increased significantly in both sexes and stayed consistently elevated during the confinement. Cytokine profiles after in vitro stimulation revealed no sex differences but resulted in significant time-dependent changes. Hemoglobin and hematocrit were significantly higher in males than females, and hemoglobin increased significantly in both sexes compared to baseline. Platelet counts were significantly higher in females than males. Leukocytes and granulocyte concentrations increased during confinement with a dip for both sexes in winter whereas lymphocytes were significantly elevated in both sexes during the confinement. CONCLUSIONS: The extreme environment of Antarctica seems to trigger some distinct stress and immune responses but-with the exception of cortisol and blood cell counts-without any major relevant sex-specific differences. Stated sex differences were shown to be independent of enhanced psychological stress and seem to be related to the environmental conditions. However, sources and consequences of these sex differences have to be further elucidated.


Asunto(s)
Ambientes Extremos , Caracteres Sexuales , Estrés Psicológico , Adulto , Regiones Antárticas , Antígenos Fúngicos/inmunología , Catecolaminas/orina , Citocinas/inmunología , Endocannabinoides/sangre , Femenino , Pruebas Hematológicas , Humanos , Hidrocortisona/metabolismo , Masculino , Persona de Mediana Edad , Mitógenos de Phytolacca americana/inmunología , Estrés Psicológico/sangre , Estrés Psicológico/inmunología , Estrés Psicológico/metabolismo , Estrés Psicológico/orina , Adulto Joven
7.
Sci Rep ; 6: 30807, 2016 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-27488946

RESUMEN

Comparative phylogeography of African savannah mammals shows a congruent pattern in which populations in West/Central Africa are distinct from populations in East/Southern Africa. However, for the lion, all African populations are currently classified as a single subspecies (Panthera leo leo), while the only remaining population in Asia is considered to be distinct (Panthera leo persica). This distinction is disputed both by morphological and genetic data. In this study we introduce the lion as a model for African phylogeography. Analyses of mtDNA sequences reveal six supported clades and a strongly supported ancestral dichotomy with northern populations (West Africa, Central Africa, North Africa/Asia) on one branch, and southern populations (North East Africa, East/Southern Africa and South West Africa) on the other. We review taxonomies and phylogenies of other large savannah mammals, illustrating that similar clades are found in other species. The described phylogeographic pattern is considered in relation to large scale environmental changes in Africa over the past 300,000 years, attributable to climate. Refugial areas, predicted by climate envelope models, further confirm the observed pattern. We support the revision of current lion taxonomy, as recognition of a northern and a southern subspecies is more parsimonious with the evolutionary history of the lion.


Asunto(s)
ADN Mitocondrial/genética , Variación Genética/genética , Leones/genética , Análisis de Secuencia de ADN/veterinaria , África , Animales , Secuencia de Bases , Evolución Biológica , Ambiente , Evolución Molecular , Leones/clasificación , Filogeografía
8.
Aktuelle Urol ; 47(3): 214-9, 2016 05.
Artículo en Alemán | MEDLINE | ID: mdl-27138235

RESUMEN

The aim of all medical treatment is "primum nihil nocere" ("First, do no harm").Restoring the integrity of intestinal microbiota and optimising the immune response in recurrent infections, especially in the urinary tract, are treatment alternatives which are closer to this target than the usual focus on antibiotic prevention of recurrence.In the future, antibiotics will continue to be recommended for the prevention of urinary tract infections on a case-by-case basis. However, the problems of an excessive use of antibiotics, e. g. resistance and long-term interference with intestinal microbiota, are forcing us to search for alternatives. The use of probiotics alone or in combination with immunotherapeutics, or the sole use of immunotherapeutics, are important treatment options, which are already routinely available in clinical practice. These therapies are focused on the pathomechanism of an infection and tackle the root cause of the problem. Phytotherapeutics or small molecules like mannose, which restricts the adherence of bacteria to the urothelium, are complementary approaches.The EAU guidelines recommend the following treatments for the long-term prevention of urinary tract infections:Oral and parenteral immunostimulants (StroVac(®)), local estrogen replacement and administration of Lactobacillus rhamnosus and Lactobacillus reuteri.


Asunto(s)
Infecciones Bacterianas/tratamiento farmacológico , Infecciones Urinarias/tratamiento farmacológico , Antibacterianos/efectos adversos , Antibacterianos/uso terapéutico , Farmacorresistencia Microbiana , Terapia de Reemplazo de Estrógeno , Humanos , Inmunoterapia/métodos , Fitoterapia/métodos , Extractos Vegetales/uso terapéutico , Probióticos/uso terapéutico , Recurrencia , Vaccinium macrocarpon
9.
Eur Cell Mater ; 31: 296-311, 2016 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-27227787

RESUMEN

Tissue barriers function as "gate keepers" between different compartments (usually blood and tissue) and are formed by specialised membrane-associated proteins, localising to the apicolateral plasma membrane domain of epithelial and endothelial cells. By sealing the paracellular space, the free diffusion of solutes and molecules across epithelia and endothelia is impeded. Thereby, tissue barriers contribute to the establishment and maintenance of a distinct internal and external environment, which is crucial during organ development and allows maintenance of an organ-specific homeostatic milieu. So far, various epithelial and endothelial tissue barriers have been described, including the blood-brain barrier, the blood-retina barrier, the blood-testis barrier, the blood-placenta barrier, and the cerebrospinal fluid (CSF)-brain barrier, which are vital for physiological function and any disturbance of these barriers can result in severe organ damage or even death. Here, we describe the identification of a novel barrier, located in the vascular bed of tendons, which we term the blood-tendon barrier (BTB). By using immunohistochemistry, transmission electron microscopy, and tracer studies we demonstrate the presence of a functional endothelial barrier within tendons restricting the passage of large blood-borne molecules into the surrounding tendon tissue. We further provide in vitro evidence that the BTB potentially contributes to the creation of a distinct internal tissue environment impacting upon the proliferation and differentiation of tendon-resident cells, effects which might be fundamental for the onset of tendon pathologies.


Asunto(s)
Vasos Sanguíneos/fisiología , Tendones/irrigación sanguínea , Adulto , Anciano , Animales , Biotina/metabolismo , Vasos Sanguíneos/ultraestructura , Western Blotting , Proliferación Celular , Células Cultivadas , Femenino , Humanos , Inmunohistoquímica , Masculino , Ratones Endogámicos C57BL , Persona de Mediana Edad , ARN/aislamiento & purificación , Coloración y Etiquetado , Tendones/citología , Tendones/ultraestructura , beta-Galactosidasa/metabolismo
10.
Eur J Pain ; 20(8): 1253-65, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26914727

RESUMEN

BACKGROUND: Chronic pain is frequent in elderly people and, especially if widespread, associated with poor mental health. We investigated whether a resilient personality protects older adults against the adverse effects of chronic pain. METHODS: Pain status [no pain, chronic local pain (CLP) and chronic widespread pain (CWP)] was determined using the American College of Rheumatologists' criteria for widespread pain in a cross-sectional sample of 724 participants aged 68-92 years drawn from the population-based KORA-Age study in Southern Germany. Depressive symptoms and resilience were assessed via the scales GDS-15 and RS-5. The relation between pain, resilience and depressive symptoms was modelled using logistic and quantile regression. RESULTS: CLP prevalence and CWP prevalence were 57.5% and 12.3%, respectively. Confounder-adjusted logistic regression indicated a fourfold risk of depressed mood (GDS-15 ≥ 5) in CWP, vs. no pain (OR = 4.08, 95% CI 1.90-8.74). However, in quantile regression, the adverse effect of CWP was significantly attenuated by resilience when looking at the GDS-15 score lower quartile (p = 0.011) and median (p = 0.011). This effect appeared to be mainly driven by participants aged 75-84 years. Confounder adjustment reduced the effect of CLP on depressive symptoms to non-significance, and effect modification by resilience was undetectable in regression models of CLP. CONCLUSIONS: Resilience was protective in the association of CWP with depressive symptoms in this analysis. Older adults with CWP may potentially benefit from interventions supporting resilience. Prospective research should investigate the protective role of resilience in the potentially self-perpetuating relation between chronic pain and depressed affect. WHAT DOES THIS STUDY ADD?: The association of chronic widespread pain with depressive symptoms in the elderly population is attenuated by resilience.


Asunto(s)
Dolor Crónico/psicología , Depresión/epidemiología , Resiliencia Psicológica , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Estudios Transversales , Depresión/psicología , Femenino , Alemania , Humanos , Modelos Logísticos , Masculino , Dimensión del Dolor , Prevalencia
11.
Biomaterials ; 77: 207-15, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26606446

RESUMEN

Artificial generated buccal mucosa equivalents are a promising approach for the reconstruction of urethral defects. Limiting in this approach is a poor blood vessel supply after transplantation, resulting in increased morbidity and necrosis. We generated a pre-vascularized buccal mucosa equivalent in a tri-culture of primary buccal epithelial cells, fibroblasts and microvascular endothelial cells, using a native collagen membrane as a scaffold. A successful pre-vascularization and dense formation of capillary-like structures at superficial areas was demonstrated. The lumen size of pre-formed blood vessels corresponded to the capillary size in vivo (10-30 µm). Comparing native with a highly cross-linked collagen membrane we found a distinct higher formation of capillary-like structures on the native membrane, apparently caused by higher secretion of angiogenic factors such as PDGF, IL-8 and angiopoietin by the cells. These capillary-like structures became functional blood vessels through anastomosis with the host vasculature after implantation in nude mice. This in vitro method should result in an accelerated blood supply to the biomaterial with cells after transplantation and increase the succes rates of the implant material.


Asunto(s)
Células Endoteliales/citología , Células Epiteliales/citología , Fibroblastos/citología , Mucosa Bucal , Organoides/irrigación sanguínea , Ingeniería de Tejidos/métodos , Trasplantes/irrigación sanguínea , Inductores de la Angiogénesis/análisis , Animales , Capilares/citología , Capilares/crecimiento & desarrollo , Células Cultivadas , Técnicas de Cocultivo , Colágeno , Prepucio/citología , Encía/citología , Xenoinjertos , Humanos , Masculino , Membranas Artificiales , Ratones , Ratones Desnudos , Organoides/citología , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/análisis , Andamios del Tejido
13.
Eur J Pharm Sci ; 71: 1-11, 2015 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-25681628

RESUMEN

Cilengitide (Cil) represents a cyclic pentapeptide, cyclo-(Arg-Gly-Asp-D-Phe-N-MeVal). Existence of an anhydrate form (A1) and a tetrahydrate form Cil1(H2O)4 has been observed. Surprisingly the anhydrate form proved to be more stable in aqueous environment compared to the tetrahydrate form. Assessment of thermodynamic stability has been carried out by competitive slurry experiments as well as by investigation of thermodynamic solubility. The lower solubility of the anhydrate form A1 can be explained by the hydrogen bonding motifs within the crystal structures. The tetrahydrate form Cil1(H2O)4 represents a special manifestation of a class of non-stoichiometric water-alcohol solvates Cil1(H2O)x(alcohol)y where methanol and ethanol can substitute water molecules in the crystal lattice of the tetrahydrate form leading to the hydrate-solvate systems Cil1(H2O)x(methanol)y named S1 and Cil1(H2O)x(ethanol)y named S2 with x ⩽ 4, y ⩽ 1 and y ⩽ 2-0.5x. The non-stoichiometric water alcohol solvates exhibit a higher solubility compared to the anhydrate form but convert rapidly to the anhydrate form in aqueous environments. Accordingly, the better soluble non-stoichiometric water alcohol solvates cannot be obtained by crystallization from aqueous media. However slurries or crystallization from solvent mixtures containing methanol and ethanol represent a means to obtain the highly soluble pseudo-polymorphs S1 and S2 and to circumvent formation of the low soluble anhydrate form A1.


Asunto(s)
Péptidos Cíclicos/química , Venenos de Serpiente/química , Cristalización , Etanol/química , Solubilidad , Solventes/química , Agua/química
14.
Phys Rev Lett ; 113(23): 237204, 2014 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-25526154

RESUMEN

Magnetic relaxation is one of the dominating features of magnetization dynamics. Depending on the magnetic structure and the experimental approach, different magnitudes of the damping parameter are reported even for a given material. In this study, we experimentally address this issue by accessing the damping parameter in the same magnetic nanotracks using different approaches: local ferromagnetic resonance (α=0.0072) and field-driven domain wall dynamics (α=0.023). The experimental results cannot fully be accounted for by modeling only roughness in micromagnetic simulations. Consequently, we have included nonlocal texture induced damping to the micromagnetic code. We find excellent agreement with the observed increased damping in the vortex structures for the same input Gilbert alpha when texture-induced nonlocal damping is included.

15.
Urologe A ; 53(10): 1468-75, 2014 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-25292309

RESUMEN

BACKGROUND: Recurrent urinary tract infections (rUTI), defined as ≥ 3 UTIs per year, mostly affect young and postmenopausal women. Treatable predisposing factors are rare. METHODS: General recommendations to reduce rUTIs lower the recurrence rate by up to approximately two thirds. Continuous long-term prophylaxis (LP) with low dose antibiotics or single postcoital doses can reduce the recurrence rate of rUTIs to as low as 5%. According to the European Association of Urology guidelines nitrofurantoin, trimethoprim and co-trimoxazole are the first-line drugs and cephalosporins or fluoroquinolones should be restricted to specific indications. Oral and parenteral immunotherapy were found to be effective in several controlled studies for prevention of rUTIs and can be combined with acute antibiotic therapy. CONCLUSIONS: Vaginal prophylaxis with estriol has proven its positive effect without serious gynecological side effects and there is also increasing evidence that cranberries prevent rUTIs but the exact mode of this therapy remains to be defined. There are also other promising modalities, such as phytotherapeutics, mannose, urine acidification, influencing bacterial intestinal and vaginal flora and the general immune response by e.g. acupuncture and inpatient rehabilitation, the therapeutic value of which still has to be proven.


Asunto(s)
Antibacterianos/administración & dosificación , Antiinflamatorios/administración & dosificación , Infecciones Bacterianas/prevención & control , Guías de Práctica Clínica como Asunto , Conducta de Reducción del Riesgo , Infecciones Urinarias/prevención & control , Urología/normas , Infecciones Bacterianas/tratamiento farmacológico , Europa (Continente) , Femenino , Humanos , Recurrencia , Infecciones Urinarias/tratamiento farmacológico
16.
Ecol Lett ; 16(11): 1414, e4, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23962143

RESUMEN

Creel et al. argue against the conservation effectiveness of fencing based on a population measure that ignores the importance of top predators to ecosystem processes. Their statistical analyses consider, first, only a subset of fenced reserves and, second, an incomplete examination of 'costs per lion.' Our original conclusions remain unaltered.


Asunto(s)
Carnívoros , Conservación de los Recursos Naturales/métodos , Leones , Densidad de Población , Animales , Humanos
17.
Nat Commun ; 4: 2054, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23784257

RESUMEN

Two-dimensional ferromagnetic layers can serve as a playground for the study of basic physical properties of various pattern forming systems by virtue of their tuneable magnetic properties. Here we use threshold photoemission magnetic circular dichroism in combination with photoemission electron microscopy to investigate ultra-thin ferromagnetic Fe/Ni/Cu(001) films in the stripe domain phase near the spin reorientation transition as a function of film thickness, temperature and effective anisotropy. Here we report a metastable domain state with domain width larger than the thermodynamically stable one as a result of a rapid reduction of the anisotropy. The transformation into the equilibrium state takes place via the propagation of a transition front, which originates from defined steps in the film thickness.

18.
Ecol Lett ; 16(5): 635-41, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23461543

RESUMEN

Conservationists often advocate for landscape approaches to wildlife management while others argue for physical separation between protected species and human communities, but direct empirical comparisons of these alternatives are scarce. We relate African lion population densities and population trends to contrasting management practices across 42 sites in 11 countries. Lion populations in fenced reserves are significantly closer to their estimated carrying capacities than unfenced populations. Whereas fenced reserves can maintain lions at 80% of their potential densities on annual management budgets of $500 km(-2) , unfenced populations require budgets in excess of $2000 km(-2) to attain half their potential densities. Lions in fenced reserves are primarily limited by density dependence, but lions in unfenced reserves are highly sensitive to human population densities in surrounding communities, and unfenced populations are frequently subjected to density-independent factors. Nearly half the unfenced lion populations may decline to near extinction over the next 20-40 years.


Asunto(s)
Carnívoros , Conservación de los Recursos Naturales/métodos , Leones , Densidad de Población , Animales , Conservación de los Recursos Naturales/economía , Ghana , Humanos , Namibia , Dinámica Poblacional , Sector Privado , Sudáfrica
19.
Minerva Urol Nefrol ; 65(1): 9-20, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23538307

RESUMEN

Urinary tract infections (UTI) are among the most frequent bacterial infections in the community and health care setting. Mostly young and, to some extent, postmenopausal women are affected by recurrent UTI (rUTI) defined as ≥3 UTI/year or ≥2 UTI/half year. In contrast, rUTI is rare in healthy men. On the other hand, rUTI are frequently found in female and male patients with complicating urological factors, e.g. urinary catheters, infection stones. Remediable predisposing factors in uncomplicated rUTI in women are rare. In complicated rUTI the success depends mainly on the possibility to eliminate or at leastimprove the complicating risk factors. Continuous antibiotic prophylaxis or postcoital prophylaxis, if there is close correlation with sexual intercourse, are most effective to prevent rUTI. Nitrofurantoin, trimethoprim (or cotrimoxazole), and fosfomycin trometamol are available as first-line drugs. Oral cephalosporins and quinolones should be restricted to specific indications. Antibiotic prophylaxis reduces the number of uropathogens in the gut and/or vaginal flora and reduces bacterial "fitness". Given the correct indication, the recurrence rate of rUTI can be reduced by about 90%. Due to possible adverse events and the concern of selecting resistant pathogens, according to the guidelines of the European Association of Urology antimicrobial prophylaxis should be considered only after counselling, behavioural modification and non-antimicrobial measures have been attempted. In postmenopausal patients vaginal substitution of oestriol should be started first. Oral or parenteral immunoprophylaxis is another option in patients with rUTI. Other possibilities with varying scientific evidence are prophylaxis with cranberry products, specific plant combinations or probiotics. The prophylaxis of catheter-associated UTI should employ strategies which result in a reduction of frequency and duration of catheter drainage of the urinary tract. The currently available catheter materials have only little influence on reducing catheter-associated rUTI.


Asunto(s)
Infecciones Urinarias/prevención & control , Adyuvantes Inmunológicos/uso terapéutico , Antiinfecciosos/uso terapéutico , Profilaxis Antibiótica , Infecciones Relacionadas con Catéteres/etiología , Infecciones Relacionadas con Catéteres/prevención & control , Coito , Diuréticos/uso terapéutico , Terapia de Reemplazo de Estrógeno , Femenino , Humanos , Higiene , Intestinos/microbiología , Masculino , Fitoterapia , Probióticos/uso terapéutico , Factores de Riesgo , Prevención Secundaria , Cateterismo Urinario/efectos adversos , Infecciones Urinarias/epidemiología , Infecciones Urinarias/etiología , Vagina/microbiología
20.
Zentralbl Chir ; 138(6): 622-9, 2013 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-22113589

RESUMEN

BACKGROUND: Insufficient nutrition in surgical patients increases perioperative morbidity, mortality, length of stay and therapy costs. Therefore, guidelines declare the integration of nutrition into the overall management as one of the key aspects of perioperative care. This study was conducted to evaluate the current clinical practice of clinical nutrition in surgical departments in Germany. METHODS: In 2009 German Surgical Society (DGCH) members in leading positions were surveyed with a standardised online questionnaire concerning their perioperative nutritional routines in elective surgery. RESULTS: From the addressed physicians n = 156 (6.24 %) answered. Of those, 86.9 % consider the nutritional status of their patients. Only 6 % use standardised nutritional screening tools. Short preoperative fasting for solid and liquid food is practiced by 65 % and 40 %, respectively. After the operation, 65 % allow intake of clear fluids on the day of surgery and 78 % initiate solid food on the day of surgery or the first postoperative day. Oral nutritional supplements are given only "sometimes" or "rarely" by 53.9 % of the respondents. CONCLUSION: The low response rate may imply the dilemma that the evidence-based benefit of perioperative nutrition does not meet sufficient interest. Even in case of a positive selection of "pro-nutrition respondents", standardised preoperative malnutrition screening is also rare. Aspects such as shorter perioperative fasting are already practiced more progressively. However, still greater efforts are needed to promote guideline-based clinical nutrition in surgical care in Germany.


Asunto(s)
Actitud del Personal de Salud , Internet , Encuestas Nutricionales , Terapia Nutricional , Atención Perioperativa , Procedimientos Quirúrgicos Operativos , Medicina Basada en la Evidencia , Alemania , Adhesión a Directriz , Humanos , Necesidades Nutricionales , Estado Nutricional , Servicio de Cirugía en Hospital , Encuestas y Cuestionarios
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