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1.
Nature ; 605(7909): 244-247, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35546195

RESUMEN

Bright quasars, powered by accretion onto billion-solar-mass black holes, already existed at the epoch of reionization, when the Universe was 0.5-1 billion years old1. How these black holes formed in such a short time is the subject of debate, particularly as they lie above the correlation between black-hole mass and galaxy dynamical mass2,3 in the local Universe. What slowed down black-hole growth, leading towards the symbiotic growth observed in the local Universe, and when this process started, has hitherto not been known, although black-hole feedback is a likely driver4. Here we report optical and near-infrared observations of a sample of quasars at redshifts 5.8 ≲ z ≲ 6.6. About half of the quasar spectra reveal broad, blueshifted absorption line troughs, tracing black-hole-driven winds with extreme outflow velocities, up to 17% of the speed of light. The fraction of quasars with such outflow winds at z ≳ 5.8 is ≈2.4 times higher than at z ≈ 2-4. We infer that outflows at z ≳ 5.8 inject large amounts of energy into the interstellar medium and suppress nuclear gas accretion, slowing down black-hole growth. The outflow phase may then mark the beginning of substantial black-hole feedback. The red optical colours of outflow quasars at z ≳ 5.8 indeed suggest that these systems are dusty and may be caught during an initial quenching phase of obscured accretion5.

2.
Arch Gynecol Obstet ; 309(4): 1353-1367, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36971845

RESUMEN

OBJECTIVE: Restrictive foramen ovale (FO) in dextro-transposition of the great arteries (d-TGA) with intact ventricular septum may lead to severe life-threatening hypoxia within the first hours of life, making urgent balloon atrial septostomy (BAS) inevitable. Reliable prenatal prediction of restrictive FO is crucial in these cases. However, current prenatal echocardiographic markers show low predictive value, and prenatal prediction often fails with fatal consequences for a subset of newborns. In this study, we described our experience and aimed to identify reliable predictive markers for BAS. METHODS: We included 45 fetuses with isolated d-TGA that were diagnosed and delivered between 2010 and 2022 in two large German tertiary referral centers. Inclusion criteria were the availability of former prenatal ultrasound reports, of stored echocardiographic videos and still images, which had to be obtained within the last 14 days prior to delivery and that were of sufficient quality for retrospective re-analysis. Cardiac parameters were retrospectively assessed and their predictive value was evaluated. RESULTS: Among the 45 included fetuses with d-TGA, 22 neonates had restrictive FO postnatally and required urgent BAS within the first 24 h of life. In contrast, 23 neonates had normal FO anatomy, but 4 of them unexpectedly showed inadequate interatrial mixing despite their normal FO anatomy, rapidly developed hypoxia and also required urgent BAS ('bad mixer'). Overall, 26 (58%) neonates required urgent BAS, whereas 19 (42%) achieved good O2 saturation and did not undergo urgent BAS. In the former prenatal ultrasound reports, restrictive FO with subsequent urgent BAS was correctly predicted in 11 of 22 cases (50% sensitivity), whereas a normal FO anatomy was correctly predicted in 19 of 23 cases (83% specificity). After current re-analysis of the stored videos and images, we identified three highly significant markers for restrictive FO: a FO diameter < 7 mm (p < 0.01), a fixed (p = 0.035) and a hypermobile (p = 0.014) FO flap. The maximum systolic flow velocities in the pulmonary veins were also significantly increased in restrictive FO (p = 0.021), but no cut-off value to reliably predict restrictive FO could be identified. If the above markers are applied, all 22 cases with restrictive FO and all 23 cases with normal FO anatomy could correctly be predicted (100% positive predictive value). Correct prediction of urgent BAS also succeeded in all 22 cases with restrictive FO (100% PPV), but naturally failed in 4 of the 23 cases with correctly predicted normal FO ('bad mixer') (82.6% negative predictive value). CONCLUSION: Precise assessment of FO size and FO flap motility allows a reliable prenatal prediction of both restrictive and normal FO anatomy postnatally. Prediction of likelihood of urgent BAS also succeeds reliably in all fetuses with restrictive FO, but identification of the small subset of fetuses that also requires urgent BAS despite their normal FO anatomy fails, because the ability of sufficient postnatal interatrial mixing cannot be predicted prenatally. Therefore, all fetuses with prenatally diagnosed d-TGA should always be delivered in a tertiary center with cardiac catheter stand-by, allowing BAS within the first 24 h after birth, regardless of their predicted FO anatomy.


Asunto(s)
Foramen Oval , Transposición de los Grandes Vasos , Embarazo , Femenino , Recién Nacido , Humanos , Foramen Oval/diagnóstico por imagen , Foramen Oval/cirugía , Transposición de los Grandes Vasos/diagnóstico por imagen , Transposición de los Grandes Vasos/cirugía , Estudios Retrospectivos , Ultrasonografía Prenatal/métodos , Feto , Arterias , Hipoxia
3.
Arch Gynecol Obstet ; 309(1): 145-158, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-36604332

RESUMEN

OBJECTIVES: To assess the spectrum of underlying pathologies, the intrauterine course and postnatal outcome of 46 fetuses with megacystis that underwent intrauterine vesico-amniotic shunting (VAS) with the Somatex® shunt in a single center. METHODS: Retrospective analysis of 46 fetuses with megacystis that underwent VAS either up to 14 + 0 weeks (early VAS), between 14 + 1 and 17 + 0 weeks (intermediate VAS) or after 17 + 0 weeks of gestation (late VAS) in a single tertiary referral center. Intrauterine course, underlying pathology and postnatal outcome were assessed and correlated with the underlying pathology and gestational age at first VAS. RESULTS: 46 fetuses underwent VAS, 41 (89%) were male and 5 (11%) were female. 28 (61%) fetuses had isolated and 18 (39%) had complex megacystis with either aneuploidy (n = 1), anorectal malformations (n = 6), cloacal malformations (n = 3), congenital anomalies overlapping with VACTER association (n = 6) or Megacystis-Microcolon Intestinal-Hypoperistalsis Syndrome (MMIHS) (n = 2). The sonographic 'keyhole sign' significantly predicted isolated megacystis (p < 0.001). 7 pregnancies were terminated, 4 babies died in the neonatal period, 1 baby died at the age of 2.5 months and 34 (74%) infants survived until last follow-up. After exclusion of the terminated pregnancies, intention-to-treat survival rate was 87%. Mean follow-up period was 24 months (range 1-72). The underlying pathology was highly variable and included posterior urethral valve (46%), hypoplastic or atretic urethra (35%), MMIHS or prune belly syndrome (10%) and primary vesico-ureteral reflux (2%). In 7% no pathology could be detected postnatally. No sonographic marker was identified to predict the underlying pathology prenatally. 14 fetuses underwent early, 24 intermediate and 8 late VAS. In the early VAS subgroup, amnion infusion prior to VAS was significantly less often necessary (7%), shunt complications were significantly less common (29%) and immediate kidney replacement therapy postnatally became less often necessary (0%). In contrast, preterm delivery ≤ 32 + 0 weeks was more common (30%) and survival rate was lower (70%) after early VAS compared to intermediate or late VAS. Overall, 90% of liveborn babies had sufficient kidney function without need for kidney replacement therapy until last follow-up, and 95% had sufficient pulmonary function without need for mechanical respiratory support. 18% of babies with complex megacystis suffered from additional health restrictions due to their major concomitant malformations. CONCLUSIONS: Our data suggest that VAS is feasible from the first trimester onward. Early intervention has the potential to preserve neonatal kidney function in the majority of cases and enables neonatal survival in up to 87% of cases. Despite successful fetal intervention, parents should be aware of the potential of mid- or long-term kidney failure and of additional health impairments due to concomitant extra-renal anomalies that cannot be excluded at time of intervention.


Asunto(s)
Amnios , Ultrasonografía Prenatal , Embarazo , Recién Nacido , Lactante , Humanos , Masculino , Femenino , Estudios Retrospectivos , Feto , Uretra
4.
Ann Oncol ; 33(9): 916-928, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35690221

RESUMEN

BACKGROUND: Anti-CD19 chimeric antigen receptor T-cell immunotherapy (CAR-T) is now a standard treatment of relapsed or refractory B-cell non-Hodgkin lymphomas; however, a significant portion of patients do not respond to CAR-T and/or experience toxicities. Lymphodepleting chemotherapy is a critical component of CAR-T that enhances CAR-T-cell engraftment, expansion, cytotoxicity, and persistence. We hypothesized that the lymphodepletion regimen might affect the safety and efficacy of CAR-T. PATIENTS AND METHODS: We compared the safety and efficacy of lymphodepletion using either fludarabine/cyclophosphamide (n = 42) or bendamustine (n = 90) before tisagenlecleucel in two cohorts of patients with relapsed or refractory large B-cell lymphomas treated consecutively at three academic institutions in the United States (University of Pennsylvania, n = 90; Oregon Health & Science University, n = 35) and Europe (University of Vienna, n = 7). Response was assessed using the Lugano 2014 criteria and toxicities were assessed by the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0 and, when possible, the American Society for Transplantation and Cellular Therapy (ASTCT) consensus grading. RESULTS: Fludarabine/cyclophosphamide led to more profound lymphocytopenia after tisagenlecleucel infusion compared with bendamustine, although the efficacy of tisagenlecleucel was similar between the two groups. We observed significant differences, however, in the frequency and severity of adverse events. In particular, patients treated with bendamustine had lower rates of cytokine release syndrome and neurotoxicity. In addition, higher rates of hematological toxicities were observed in patients receiving fludarabine/cyclophosphamide. Bendamustine-treated patients had higher nadir neutrophil counts, hemoglobin levels, and platelet counts, as well as a shorter time to blood count recovery, and received fewer platelet and red cell transfusions. Fewer episodes of infection, neutropenic fever, and post-infusion hospitalization were observed in the bendamustine cohort compared with patients receiving fludarabine/cyclophosphamide. CONCLUSIONS: Bendamustine for lymphodepletion before tisagenlecleucel has efficacy similar to fludarabine/cyclophosphamide with reduced toxicities, including cytokine release syndrome, neurotoxicity, infectious and hematological toxicities, as well as reduced hospital utilization.


Asunto(s)
Clorhidrato de Bendamustina , Inmunoterapia Adoptiva , Depleción Linfocítica , Linfoma de Células B Grandes Difuso , Receptores de Antígenos de Linfocitos T , Clorhidrato de Bendamustina/efectos adversos , Clorhidrato de Bendamustina/uso terapéutico , Ciclofosfamida/uso terapéutico , Síndrome de Liberación de Citoquinas/tratamiento farmacológico , Humanos , Inmunoterapia Adoptiva/métodos , Depleción Linfocítica/métodos , Linfoma de Células B Grandes Difuso/terapia , Receptores de Antígenos de Linfocitos T/uso terapéutico
5.
Neuroimage ; 228: 117692, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33385546

RESUMEN

Diffusion MRI (dMRI) represents one of the few methods for mapping brain fiber orientations non-invasively. Unfortunately, dMRI fiber mapping is an indirect method that relies on inference from measured diffusion patterns. Comparing dMRI results with other modalities is a way to improve the interpretation of dMRI data and help advance dMRI technologies. Here, we present methods for comparing dMRI fiber orientation estimates with optical imaging of fluorescently labeled neurofilaments and vasculature in 3D human and primate brain tissue cuboids cleared using CLARITY. The recent advancements in tissue clearing provide a new opportunity to histologically map fibers projecting in 3D, which represents a captivating complement to dMRI measurements. In this work, we demonstrate the capability to directly compare dMRI and CLARITY in the same human brain tissue and assess multiple approaches for extracting fiber orientation estimates from CLARITY data. We estimate the three-dimensional neuronal fiber and vasculature orientations from neurofilament and vasculature stained CLARITY images by calculating the tertiary eigenvector of structure tensors. We then extend CLARITY orientation estimates to an orientation distribution function (ODF) formalism by summing multiple sub-voxel structure tensor orientation estimates. In a sample containing part of the human thalamus, there is a mean angular difference of 19o±15o between the primary eigenvectors of the dMRI tensors and the tertiary eigenvectors from the CLARITY neurofilament stain. We also demonstrate evidence that vascular compartments do not affect the dMRI orientation estimates by showing an apparent lack of correspondence (mean angular difference = 49o±23o) between the orientation of the dMRI tensors and the structure tensors in the vasculature stained CLARITY images. In a macaque brain dataset, we examine how the CLARITY feature extraction depends on the chosen feature extraction parameters. By varying the volume of tissue over which the structure tensor estimates are derived, we show that orientation estimates are noisier with more spurious ODF peaks for sub-voxels below 30 µm3 and that, for our data, the optimal gray matter sub-voxel size is between 62.5 µm3 and 125 µm3. The example experiments presented here represent an important advancement towards robust multi-modal MRI-CLARITY comparisons.


Asunto(s)
Encéfalo/anatomía & histología , Sustancia Gris/anatomía & histología , Procesamiento de Imagen Asistido por Computador/métodos , Imagen Multimodal/métodos , Neuroimagen/métodos , Sustancia Blanca/anatomía & histología , Animales , Imagen de Difusión por Resonancia Magnética/métodos , Humanos , Imagenología Tridimensional/métodos , Macaca , Imagen Óptica/métodos
6.
J Fish Dis ; 44(6): 793-801, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33332625

RESUMEN

Infection with Veronaea botryosa can result in rare cutaneous or disseminated, granulomatous to pyogranulomatous phaeohyphomycosis in humans, although disease due to the fungus has also been reported in non-mammalian vertebrates. This report documents disease due to V. botryosa in captive, juvenile to subadult or young adult white sturgeon (Acipenser transmontanus Richardson) from California USA and complements a previous report of the disease in captive Siberian sturgeon (Acipenser baerii) from Florida USA. Pathological examinations revealed granulomatous to pyogranulomatous inflammation of multiple organs. Isolates of the fungal agent were phenotypically consistent with V. botryosa, and molecular analyses of the D1/D2 region of the fungal 28S rRNA gene and the internal transcribed spacer (ITS) region located between the fungal 18S and 28S rRNA genes confirmed the aetiologic agent as V. botryosa. The disease in captive sturgeon results in a considerable economic encumbrance to the producer due to the loss of the cumulative financial resources invested in the production of older subadult to young adult sturgeon.


Asunto(s)
Ascomicetos/fisiología , Enfermedades de los Peces/microbiología , Peces , Feohifomicosis/veterinaria , Animales , California , Femenino , Masculino , Feohifomicosis/microbiología
7.
Arch Gynecol Obstet ; 302(1): 133-140, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32449061

RESUMEN

PURPOSE: The objective was to evaluate the feasibility of vesicoamniotic shunting (VAS) in the first trimester with the Somatex® intrauterine shunt and report on complications and neonatal outcome. METHODS: Retrospective cohort study of all VAS before 14 weeks at two tertiary fetal medicine centres from 2015 to 2018 using a Somatex® intrauterine shunt. All patients with a first trimester diagnosis of megacystis in male fetuses with a longitudinal bladder diameter of at least 15 mm were offered VAS. All patients that opted for VAS after counselling by prenatal medicine specialists, neonatologists and pediatric nephrologists were included in the study. Charts were reviewed for complications, obstetric and neonatal outcomes. RESULTS: Ten VAS were performed during the study period in male fetuses at a median GA of 13.3 (12.6-13.9) weeks. There were two terminations of pregnancy (TOP) due to additional malformations and one IUFD. Overall there were four shunt dislocations (40%); three of those between 25-30 weeks GA. Seven neonates were born alive at a median GA of 35.1 weeks (31.0-38.9). There was one neonatal death due to pulmonary hypoplasia. Neonatal kidney function was normal in the six neonates surviving the neonatal period. After exclusion of TOP, perinatal survival was 75%, and 85.7% if only live-born children were considered. CONCLUSION: VAS in the first trimester is feasible with the Somatex® Intrauterine shunt with low fetal and maternal complication rates. Neonatal survival rates are high due to a reduction in pulmonary hypoplasia and the rate of renal failure at birth is very low. VAS can be safely offered from the late first trimester using the Somatex® intrauterine shunt.


Asunto(s)
Ultrasonografía Prenatal/métodos , Vejiga Urinaria/anomalías , Sistema Urinario/anomalías , Femenino , Feto , Humanos , Masculino , Embarazo , Primer Trimestre del Embarazo , Estudios Retrospectivos
8.
Yale J Biol Med ; 92(2): 259-270, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31249487

RESUMEN

Circadian disruption has been linked to markers for poor health outcomes in humans and animal models. What is it about circadian disruption that is problematic? One hypothesis is that phase resetting of the circadian system, which occurs in response to changes in environmental timing cues, leads to internal desynchrony within the organism. Internal desynchrony is understood as acute changes in phase relationships between biological rhythms from different cell groups, tissues, or organs within the body. Do we have strong evidence for internal desynchrony associated with or caused by circadian clock resetting? Here we review the literature, highlighting several key studies from measures of gene expression in laboratory rodents. We conclude that current evidence offers strong support for the premise that some protocols for light-induced resetting are associated with internal desynchrony. It is important to continue research to test whether internal desynchrony is necessary and/or sufficient for negative health impact of circadian disruption.


Asunto(s)
Relojes Circadianos/fisiología , Ritmo Circadiano/fisiología , Periodicidad , Fotoperiodo , Animales , Relojes Circadianos/genética , Relojes Circadianos/efectos de la radiación , Ritmo Circadiano/genética , Ritmo Circadiano/efectos de la radiación , Regulación de la Expresión Génica/efectos de la radiación , Humanos , Luz , Núcleo Supraquiasmático/metabolismo , Núcleo Supraquiasmático/fisiopatología , Núcleo Supraquiasmático/efectos de la radiación
9.
Clin Genet ; 94(3-4): 373-380, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29926465

RESUMEN

By describing 10 new patients recruited in centres for Human Genetics, we further delineate the clinical spectrum of a Crouzon-like craniosynostosis disorder, officially termed craniosynostosis and dental anomalies (MIM614188). Singularly, it is inherited according to an autosomal recessive mode of inheritance. We identified six missense mutations in IL11RA, a gene encoding the alpha subunit of interleukin 11 receptor, 4 of them being novel, including 2 in the Ig-like C2-type domain. A subset of patients had an associated connective tissue disorder with joint hypermobility and intervertebral discs fragility. A smaller number of teeth anomalies than that previously reported in the two large series of patients evaluated in dental institutes points toward an ascertainment bias.


Asunto(s)
Disostosis Craneofacial/genética , Genes Recesivos , Subunidad alfa del Receptor de Interleucina-11/genética , Adolescente , Adulto , Niño , Preescolar , Disostosis Craneofacial/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Mutación Missense
11.
Nature ; 491(7425): 594-8, 2012 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-23151476

RESUMEN

The daily solar cycle allows organisms to synchronize their circadian rhythms and sleep-wake cycles to the correct temporal niche. Changes in day-length, shift-work, and transmeridian travel lead to mood alterations and cognitive function deficits. Sleep deprivation and circadian disruption underlie mood and cognitive disorders associated with irregular light schedules. Whether irregular light schedules directly affect mood and cognitive functions in the context of normal sleep and circadian rhythms remains unclear. Here we show, using an aberrant light cycle that neither changes the amount and architecture of sleep nor causes changes in the circadian timing system, that light directly regulates mood-related behaviours and cognitive functions in mice. Animals exposed to the aberrant light cycle maintain daily corticosterone rhythms, but the overall levels of corticosterone are increased. Despite normal circadian and sleep structures, these animals show increased depression-like behaviours and impaired hippocampal long-term potentiation and learning. Administration of the antidepressant drugs fluoxetine or desipramine restores learning in mice exposed to the aberrant light cycle, suggesting that the mood deficit precedes the learning impairments. To determine the retinal circuits underlying this impairment of mood and learning, we examined the behavioural consequences of this light cycle in animals that lack intrinsically photosensitive retinal ganglion cells. In these animals, the aberrant light cycle does not impair mood and learning, despite the presence of the conventional retinal ganglion cells and the ability of these animals to detect light for image formation. These findings demonstrate the ability of light to influence cognitive and mood functions directly through intrinsically photosensitive retinal ganglion cells.


Asunto(s)
Afecto/efectos de la radiación , Aprendizaje/efectos de la radiación , Luz , Células Ganglionares de la Retina/metabolismo , Células Ganglionares de la Retina/efectos de la radiación , Opsinas de Bastones , Afecto/efectos de los fármacos , Afecto/fisiología , Animales , Antidepresivos/farmacología , Regulación de la Temperatura Corporal/fisiología , Regulación de la Temperatura Corporal/efectos de la radiación , Ritmo Circadiano/fisiología , Cognición/efectos de los fármacos , Cognición/fisiología , Cognición/efectos de la radiación , Corticosterona/metabolismo , Depresión/etiología , Depresión/fisiopatología , Desipramina/farmacología , Fluoxetina/farmacología , Aprendizaje/efectos de los fármacos , Aprendizaje/fisiología , Potenciación a Largo Plazo/efectos de los fármacos , Masculino , Memoria/fisiología , Memoria/efectos de la radiación , Ratones , Fotoperiodo , Células Ganglionares de la Retina/efectos de los fármacos , Opsinas de Bastones/análisis , Sueño/fisiología , Vigilia/fisiología
12.
Eur Cell Mater ; 33: 294-307, 2017 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-28537650

RESUMEN

Tendon disorders are frequent both in human and veterinary medicine with high re-injury rates and unsatisfactory therapeutic treatments. Application of naked, chemically-modified mRNA (cmRNA), encoding for therapeutic proteins, is an innovative approach to address tendon healing. In the current study, we demonstrated that injection of naked cmRNA, diluted in a glucose-containing solution, into tendons resulted in high protein expression in healthy and experimentally-injured tendons. Injection of bone morphogenetic protein 7 (BMP-7)-encoding cmRNA resulted in a significantly higher expression of BMP-7 protein and reduced formation of collagen type III, compared to vehicle control. Moreover, in a large animal model, reporter protein expression was detectable not only in healthy, but also in experimentally-injured, severely inflamed tendons. Summarising, these results demonstrated the potential of cmRNAs encoding for therapeutic proteins as a new class of drugs for the treatment of tendon disorders.


Asunto(s)
ARN Mensajero/uso terapéutico , Tendones/patología , Cicatrización de Heridas , Animales , Calcáneo/lesiones , Calcáneo/patología , Femenino , Cinética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas Sprague-Dawley , Ovinos , Solventes , Traumatismos de los Tendones/patología , Traumatismos de los Tendones/terapia , Transfección
13.
Phys Chem Chem Phys ; 19(24): 16087-16094, 2017 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-28598474

RESUMEN

We report the observation of anisotropic longitudinal electronic relaxation in nitroxide radicals under typical dynamic nuclear polarization conditions. This anisotropy affects the efficiency of dynamic nuclear polarization at cryogenic temperatures of 4 K and high magnetic fields of 6.7 T. Under our experimental conditions, the electron paramagnetic resonance spectrum of nitroxides such as TEMPOL (4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl) is only partly averaged by electronic spectral diffusion, so that the relaxation times T1e(ω) vary across the spectrum. We demonstrate how the anisotropy of T1e(ω) can be taken into account in simple DNP models.

15.
Oecologia ; 179(1): 249-59, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25964063

RESUMEN

Biotic plant-soil interactions and land-use intensity are known to affect plant individual fitness as well as competitiveness and therefore plant-species abundances in communities. Therefore, a link between soil biota and land-use intensity on local abundance of plant species in grasslands can be expected. In two greenhouse experiments, we investigated the effects of soil biota from grassland sites differing in land-use intensity on three grass species that vary in local abundances along this land-use gradient. We were interested in those soil-biota effects that are associated with land-use intensity, and whether these effects act directly or indirectly. Therefore, we grew the three plant species in two separate experiments as single individuals and in mixtures and compared their performance. As single plants, all three grasses showed a similar performance with and without soil biota. In contrast, in mixtures growth of the species in response to the presence or absence of soil biota differed. This resulted in different soil-biota effects that tend to correspond with patterns of species-specific abundances in the field for two of the three species tested. Our results highlight the importance of indirect interactions between plants and soil microorganisms and suggest that combined effects of soil biota and plant-plant interactions are involved in structuring plant communities. In conclusion, our experiments suggest that soil biota may have the potential to alter effects of plant-plant interactions and therefore influence plant-species abundances and diversity in grasslands.


Asunto(s)
Biota , Pradera , Poaceae/crecimiento & desarrollo , Microbiología del Suelo , Biodiversidad , Ecosistema , Alemania , Especificidad de la Especie
16.
Anaesthesia ; 70(8): 962-8, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25827168

RESUMEN

The VivaSight-DL(™) is a new single-use double-lumen endobronchial tube with an integrated camera. We studied this device in 151 consecutive patients scheduled for elective thoracic surgery in four different hospitals. Endobronchial intubation was successful in 148 patients (98%) (95% CI 94-99%). Median (IQR [range]) endobronchial intubation time was 59 (47-82 [17-932]) s and lung isolation was successfully achieved in 147 (99%) patients (95% CI 96-99%). A fibreoptic bronchoscope was required to assist endobronchial tube placement in 19 (13%) patients (95% CI 8-19%). Sore throat was reported by 37 (25%) patients (95% CI 18-33%), but no major complications were observed. We have reported the successful use of the VivaSight double-lumen tube for endobronchial intubation in a multicentre observational trial.


Asunto(s)
Intubación Intratraqueal/instrumentación , Anciano , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Procedimientos Quirúrgicos Torácicos
17.
J Vet Pharmacol Ther ; 38(6): 606-15, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25876672

RESUMEN

The use of an extended release ceftiofur crystalline-free acid formulation (CCFA, Excede For Swine(®) , Pfizer Animal Health) in koi was evaluated after administration of single intramuscular (i.m.) or intracoelomic (i.c.) doses. Twenty koi were divided randomly into a control group and four treatment groups (20 mg/kg i.m., 60 mg/kg i.m., 30 mg/kg i.c., and 60 mg/kg i.c.). Serum ceftiofur-free acid equivalents (CFAE) concentrations were quantified. The pharmacokinetic data were analyzed using a nonlinear mixed-effects approach. Following a CCFA injection of 60 mg/kg i.m., time durations that serum CFAE concentrations were above the target concentration of 4 µg/mL ranged from 0.4 to 2.5 weeks in 3 of 4 fish, while serum CFAE concentrations remained below 4 µg/mL for lower doses evaluated. Substantial inter-individual variations and intra-individual fluctuations of CFAE concentrations were observed for all treatment groups. Histological findings following euthanasia included aseptic granulomatous reactions, but no systemic adverse effects were detected. Given the unpredictable time vs. CFAE concentration profiles for treated koi, the authors would not recommend this product for therapeutic use in koi at this time. Further research would be necessary to correlate serum and tissue concentrations and to better establish MIC data for Aeromonas spp. isolated from naturally infected koi.


Asunto(s)
Antibacterianos/farmacocinética , Carpas/metabolismo , Cefalosporinas/farmacocinética , Animales , Antibacterianos/administración & dosificación , Antibacterianos/sangre , Cefalosporinas/administración & dosificación , Cefalosporinas/sangre , Preparaciones de Acción Retardada , Inyecciones Intramusculares/veterinaria
18.
Dis Aquat Organ ; 111(3): 219-27, 2014 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-25320034

RESUMEN

In 2009, juvenile pallid sturgeon Scaphirhynchus albus, reared at the Blind Pony State Fish Hatchery (Missouri, USA) to replenish dwindling wild stocks, experienced mass mortality. Histological examination revealed extensive necrosis of the haematopoietic tissues, and a virus was isolated from affected organs in cell culture and then observed by electron microscopy. Experimental infection studies revealed that the virus is highly pathogenic to juvenile pallid sturgeon, one of several species of sturgeon currently listed as Endangered. The DNA sequence of the full length major capsid protein gene of the virus was identical to that of the species Frog virus 3 (FV3), the type species for the genus Ranavirus, originally isolated from northern leopard frog Lithobates pipiens. Although FV3 infections and epizootics in amphibians and reptiles are well documented, there is only 1 prior report of a natural infection of FV3 in fish. Our results illustrate the broad potential host range for FV3, with the known potential to cause significant mortality in poikilothermic vertebrates across 3 taxonomic classes including bony fishes, anuran and caudate amphibians, and squamate and testudine reptiles.


Asunto(s)
Infecciones por Virus ADN/veterinaria , Enfermedades de los Peces/virología , Ranavirus/aislamiento & purificación , Animales , Infecciones por Virus ADN/virología , Peces , Especificidad del Huésped
19.
J Zoo Wildl Med ; 45(1): 184-9, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24712183

RESUMEN

The purpose of this study was to compare and define the normal cross-sectional gross and computed tomographic (CT) anatomy for a species of boney fish to better gain insight into the use of advanced diagnostic imaging for future clinical cases. The pacu (Colossoma macropomum) was used because of its widespread presence in the aquarium trade, its relatively large body size, and its importance in the research and aquaculture settings. Transverse 0.6-mm CT images of three cadaver fish were obtained and compared to corresponding frozen cross sections of the fish. Relevant anatomic structures were identified and labeled at each level; the Hounsfield unit density of major organs was established. The images presented good anatomic detail and provide a reference for future research and clinical investigation.


Asunto(s)
Characiformes/anatomía & histología , Tomografía Computarizada por Rayos X/veterinaria , Animales
20.
J Zoo Wildl Med ; 45(4): 866-74, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25632675

RESUMEN

Wounds in reptiles are a common reason for presentation to a veterinarian. At this time there is limited information on effective topical medications to aid in wound closure. The objectives of this study were to translate the splinted, full-thickness dermal wound model, validated in mice, to the bearded dragon (Pogona vitticeps) and to determine the effect of topical becaplermin (BP), a platelet-derived growth factor (0.01%), on the rate of wound closure. Ten bearded dragons were anesthetized and two full-thickness cutaneous wounds were made on the dorsum of each lizard. Encircling splints were applied surrounding each wound and subsequently covered by a semi-occlusive dressing. Five lizards had one wound treated with BP and the adjacent wound treated with a vehicle control. Five additional lizards had one wound treated with saline and the second wound treated with a vehicle control. Wounds were imaged daily, and the wound area was measured using digital image analysis. The change in percentage wound closure over 17 days and the time to 50% wound closure was compared among the four treatment groups. There was no significant difference in wound closure rates between BP-treated and saline-treated wounds or in the time to 50% wound closure between any treatments. Vehicle-treated wounds adjacent to saline-treated wounds closed significantly slower than did BP (P < 0.010), saline (P < 0.001), and vehicle-treated wounds adjacent to BP-treated wounds (P < 0.013). Our preliminary study indicates that the splinted wound model, with modifications, may be used to determine wound closure rates in bearded dragons. When compared with saline, BP did not have a significant effect on wound closure rates, while the vehicle alone delayed wound closure. Histologic analysis of experimentally created wounds throughout the wound healing process is needed to further evaluate the effects of these treatments on reptile dermal wound healing.


Asunto(s)
Lagartos , Factor de Crecimiento Derivado de Plaquetas/farmacología , Cicatrización de Heridas/efectos de los fármacos , Animales , Femenino , Masculino
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