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1.
Trials ; 25(1): 334, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773643

RESUMEN

INTRODUCTION: The standard treatment for patients with focal drug-resistant epilepsy (DRE) who are not eligible for open brain surgery is the continuation of anti-seizure medication (ASM) and neuromodulation. This treatment does not cure epilepsy but only decreases severity. The PRECISION trial offers a non-invasive, possibly curative intervention for these patients, which consist of a single stereotactic radiotherapy (SRT) treatment. Previous studies have shown promising results of SRT in this patient population. Nevertheless, this intervention is not yet available and reimbursed in the Netherlands. We hypothesize that: SRT is a superior treatment option compared to palliative standard of care, for patients with focal DRE, not eligible for open surgery, resulting in a higher reduction of seizure frequency (with 50% of the patients reaching a 75% seizure frequency reduction at 2 years follow-up). METHODS: In this waitlist-controlled phase 3 clinical trial, participants are randomly assigned in a 1:1 ratio to either receive SRT as the intervention, while the standard treatments consist of ASM continuation and neuromodulation. After 2-year follow-up, patients randomized for the standard treatment (waitlist-control group) are offered SRT. Patients aged ≥ 18 years with focal DRE and a pretreatment defined epileptogenic zone (EZ) not eligible for open surgery will be included. The intervention is a LINAC-based single fraction (24 Gy) SRT treatment. The target volume is defined as the epileptogenic zone (EZ) on all (non) invasive examinations. The seizure frequency will be monitored on a daily basis using an electronic diary and an automatic seizure detection system during the night. Potential side effects are evaluated using advanced MRI, cognitive evaluation, Common Toxicity Criteria, and patient-reported outcome questionnaires. In addition, the cost-effectiveness of the SRT treatment will be evaluated. DISCUSSION: This is the first randomized trial comparing SRT with standard of care in patients with DRE, non-eligible for open surgery. The primary objective is to determine whether SRT significantly reduces the seizure frequency 2 years after treatment. The results of this trial can influence the current clinical practice and medical cost reimbursement in the Netherlands for patients with focal DRE who are not eligible for open surgery, providing a non-invasive curative treatment option. TRIAL REGISTRATION: Clinicaltrials.gov Identifier: NCT05182437. Registered on September 27, 2021.


Asunto(s)
Epilepsia Refractaria , Radiocirugia , Humanos , Anticonvulsivantes/uso terapéutico , Ensayos Clínicos Fase III como Asunto , Análisis Costo-Beneficio , Epilepsia Refractaria/cirugía , Epilepsias Parciales/cirugía , Países Bajos , Radiocirugia/efectos adversos , Radiocirugia/métodos , Factores de Tiempo , Resultado del Tratamiento , Listas de Espera
2.
Infection ; 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38499828

RESUMEN

PURPOSE: In contrast to adults, immune protection against SARS-CoV-2 in children and adolescents with natural or hybrid immunity is still poorly understood. The aim of this study was to analyze different immune compartments in different age groups and whether humoral immune reactions correlate with a cellular immune response. METHODS: 72 children and adolescents with a preceding SARS-CoV-2 infection were recruited. 37 were vaccinated with an RNA vaccine (BNT162b2). Humoral immunity was analyzed 3-26 months (median 10 months) after infection by measuring Spike protein (S), nucleocapsid (NCP), and neutralizing antibodies (nAB). Cellular immunity was analyzed using a SARS-CoV-2-specific interferon-γ release assay (IGRA). RESULTS: All children and adolescents had S antibodies; titers were higher in those with hybrid immunity (14,900 BAU/ml vs. 2118 BAU/ml). NCP antibodies were detectable in > 90%. Neutralizing antibodies (nAB) were more frequently detected (90%) with higher titers (1914 RLU) in adolescents with hybrid immunity than in children with natural immunity (62.5%, 476 RLU). Children with natural immunity were less likely to have reactive IGRAs (43.8%) than adolescents with hybrid immunity (85%). The amount of interferon-γ released by T cells was comparable in natural and hybrid immunity. CONCLUSION: Spike antibodies are the most reliable markers to monitor an immune reaction against SARS-CoV-2. High antibody titers of spike antibodies and nAB correlated with cellular immunity, a phenomenon found only in adolescents with hybrid immunity. Hybrid immunity is associated with markedly higher antibody titers and a higher probability of a cellular immune response than a natural immunity.

3.
Exp Neurol ; 374: 114706, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38311020

RESUMEN

Motor cortical circuit functions depend on the coordinated fine-tuning of two functionally diverse neuronal populations: glutamatergic pyramidal neurons providing synaptic excitation and GABAergic interneurons adjusting the response of pyramidal neurons through synaptic inhibition. Microglia are brain resident macrophages which dynamically refine cortical circuits by monitoring perineuronal extracellular matrix and remodelling synapses. Previously, we showed that colony-stimulating factor 1 receptor (CSF1R)-mediated myeloid cell depletion extended the lifespan, but impaired motor functions of MBP29 mice, a mouse model for multiple system atrophy. In order to better understand the mechanisms underlying these motor deficits we characterized the microglial involvement in the cortical balance of GABAergic interneurons and glutamatergic pyramidal neurons in 4-months-old MBP29 mice following CSF1R inhibition for 12 weeks. Lack of myeloid cells resulted in a decreased number of COUP TF1 interacting protein 2-positive (CTIP2+) layer V pyramidal neurons, however in a proportional increase of calretinin-positive GABAergic interneurons in MBP29 mice. While myeloid cell depletion did not alter the expression of important presynaptic and postsynaptic proteins, the loss of cortical perineuronal net area was attenuated by CSF1R inhibition in MBP29 mice. These cortical changes may restrict synaptic plasticity and potentially modify parvalbumin-positive perisomatic input. Collectively, this study suggests, that the lack of myeloid cells shifts the neuronal balance toward an increased inhibitory connectivity in the motor cortex of MBP29 mice thereby potentially deteriorating motor functions.


Asunto(s)
Corteza Motora , Atrofia de Múltiples Sistemas , Ratones , Animales , Neuronas , Células Piramidales/fisiología , Interneuronas/fisiología , Proteínas Tirosina Quinasas Receptoras , Células Mieloides
4.
Acta Neuropathol Commun ; 12(1): 1, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38167307

RESUMEN

The growing recognition of a dichotomous role of astrocytes in neurodegenerative processes has heightened the need for unraveling distinct astrocytic subtypes in neurological disorders. In multiple system atrophy (MSA), a rare, rapidly progressing atypical Parkinsonian disease characterized by increased astrocyte reactivity. However the specific contribution of astrocyte subtypes to neuropathology remains elusive. Hence, we first set out to profile glial fibrillary acidic protein levels in astrocytes across the human post mortem motor cortex, putamen, and substantia nigra of MSA patients and observed an overall profound astrocytic response. Matching the post mortem human findings, a similar astrocytic phenotype was present in a transgenic MSA mouse model. Notably, MSA mice exhibited a decreased expression of the glutamate transporter 1 and glutamate aspartate transporter in the basal ganglia, but not the motor cortex. We developed an optimized astrocyte isolation protocol based on magnetic-activated cell sorting via ATPase Na+/K+ transporting subunit beta 2 and profiled the transcriptomic landscape of striatal and cortical astrocytes in transgenic MSA mice. The gene expression profile of astrocytes in the motor cortex displayed an anti-inflammatory signature with increased oligodendroglial and pro-myelinogenic expression pattern. In contrast, striatal astrocytes were defined by elevated pro-inflammatory transcripts accompanied by dysregulated genes involved in homeostatic functions for lipid and calcium metabolism. These findings provide new insights into a region-dependent, dichotomous astrocytic response-potentially beneficial in the cortex and harmful in the striatum-in MSA suggesting a differential role of astrocytes in MSA-related neurodegenerative processes.


Asunto(s)
Atrofia de Múltiples Sistemas , Trastornos Parkinsonianos , Humanos , Ratones , Animales , Atrofia de Múltiples Sistemas/patología , Astrocitos/metabolismo , Trastornos Parkinsonianos/patología , Cuerpo Estriado/metabolismo , Sustancia Negra/metabolismo , Ratones Transgénicos
7.
Laryngorhinootologie ; 102(2): 89-99, 2023 02.
Artículo en Alemán | MEDLINE | ID: mdl-36750110

RESUMEN

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a multifactorial inflammatory disease of the mucous membranes of the nose and sinuses. Eosinophilic inflammation is described as a common endotype. The anti-IL5 antibody mepolizumab was approved in November 2021 as an add-on therapy to intranasal glucocorticosteroids for the treatment of adults with severe chronic rhinosinusitis with nasal polyps when systemic glucocorticosteroids or surgery do not provide adequate disease control. While national and international recommendations exist for the use of mepolizumab in CRSwNP, it has not yet been adequately specified how this therapy is to be monitored, what follow-up documentation is necessary, and when it should be terminated if necessary. METHODS: A literature search was performed to analyze previous data on the treatment of CRSwNP with mepolizumab and to determine the available evidence by searching Medline, Pubmed, the national and international trial and guideline registries and the Cochrane Library. Human studies published in the period up to and including 10/2022 were considered. RESULTS: Based on the international literature and previous experience by an expert panel, recommendations for follow-up, adherence to therapy intervals and possible therapy breaks, as well as termination of therapy when using mepolizumab for the indication CRSwNP in the German health care system are given on the basis of a documentation sheet. CONCLUSIONS: Understanding the immunological basis of CRSwNP opens up new non-surgical therapeutic approaches with biologics for patients with severe, uncontrolled courses. Here, we provide recommendations for follow-up, adherence to therapy intervals, possible therapy pauses, or discontinuation of therapy when mepolizumab is used as add-on therapy with intranasal glucocorticosteroids to treat adult patients with severe CRSwNP that cannot be adequately controlled with systemic glucocorticosteroids and/or surgical intervention.


Asunto(s)
Medicina Ambiental , Pólipos Nasales , Procedimientos Quírurgicos Nasales , Rinitis , Sinusitis , Adulto , Humanos , Rinitis/tratamiento farmacológico , Enfermedad Crónica , Sinusitis/tratamiento farmacológico , Atención a la Salud
8.
J Comp Pathol ; 201: 37-40, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36701871

RESUMEN

An adult male greater bulldog bat (Noctilio leporinus) was found dead in a suburban area in the municipality of Patos, Paraiba, northeastern Brazil. At post-mortem examination, the bat was emaciated and had multifocal to coalescent grey, crusted, dry, scaly cutaneous lesions, irregularly distributed over the dorsal thoracoabdominal region, muzzle, labial commissures, ears and dorsoventral surfaces of the patagia. Histopathology revealed numerous longitudinal and transverse sections of fungal organisms, with weakly basophilic walls, associated with multifocal areas of ulceration of the epidermis, necrosis, rupture and discontinuity of collagen fibres in the dermis without any inflammatory response. Molecular identification matched the organism to Cladosporium spp, Curvularia spp, Exserohilum spp, Bipolaris spp (100%) and Alternaria spp (97%), all of which have been associated with phaeohyphomycosis. Phaeohyphomycosis should be included as a differential diagnosis of cutaneous lesions in chiropterans.


Asunto(s)
Quirópteros , Feohifomicosis , Masculino , Animales , Brasil , Feohifomicosis/veterinaria , Piel , Cladosporium
9.
Laryngorhinootologie ; 101(11): 855-865, 2022 11.
Artículo en Alemán | MEDLINE | ID: mdl-36150698

RESUMEN

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a multifactorial inflammatory disease of the nasal and paranasal mucosa. A Type-2 inflammation is described as the most common endotype. Since October 2019 the anti-IL-4/-IL-13 antibody dupilumab has been approved in Germany as an add-on therapy to intranasal corticosteroids for the treatment of adults with severe chronic rhinosinusitis with nasal polyps, when systemic corticosteroids alone or surgery do not provide adequate disease control. While recommendations for the use of dupilumab in CRSwNP exist at both national and international levels, until now it has not been adequately established, how therapy should be monitored and when it should be discontinued in the German Health Care System. METHODS: A literature search was performed analyzing previous data on the treatment of CRSwNP with dupilumab and to determine the available evidence by searching Medline, Pubmed, the national and international trial and guideline registries and the Cochrane Library. Human studies published in the period up to 05/2022 were included. RESULTS: Based on international literature and previous experience, recommendations are given by an expert panel for follow-up and possible therapy breaks, therapy intervals or termination of therapy when using dupilumab for the indication CRSwNP in the German health care system based on a documentation form. CONCLUSIONS: Understanding the immunological basis of CRSwNP opens new non-surgical therapy approaches with biologics for patients with severe courses. The authors give recommendations for follow-up, possible therapy breaks, therapy intervals and a termination for dupilumab treatment as add-on therapy with intranasal corticosteroids for the treatment of adult patients with severe CRSwNP that cannot be adequately controlled with systemic corticosteroids and/or surgical intervention.


Asunto(s)
Pólipos Nasales , Rinitis , Sinusitis , Adulto , Humanos , Pólipos Nasales/tratamiento farmacológico , Rinitis/tratamiento farmacológico , Sinusitis/tratamiento farmacológico , Enfermedad Crónica , Corticoesteroides/uso terapéutico , Atención a la Salud , Documentación
11.
Clin Neuroradiol ; 32(1): 133-140, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34709408

RESUMEN

PURPOSE: We hypothesize that the detectability of early ischemic changes on non-contrast computed tomography (NCCT) is limited in hyperacute stroke for both human and machine-learning based evaluation. In short onset-time-to-imaging (OTI), the CT angiography collateral status may identify fast stroke progressors better than early ischemic changes quantified by ASPECTS. METHODS: In this retrospective, monocenter study, CT angiography collaterals (Tan score) and ASPECTS on acute and follow-up NCCT were evaluated by two raters. Additionally, a machine-learning algorithm evaluated the ASPECTS scale on the NCCT (e-ASPECTS). In this study 136 patients from 03/2015 to 12/2019 with occlusion of the main segment of the middle cerebral artery, with a defined symptom-onset-time and successful mechanical thrombectomy (MT) (modified treatment in cerebral infarction score mTICI = 2c or 3) were evaluated. RESULTS: Agreement between acute and follow-up ASPECTS were found to depend on OTI for both human (Intraclass correlation coefficient, ICC = 0.43 for OTI < 100 min, ICC = 0.57 for OTI 100-200 min, ICC = 0.81 for OTI ≥ 200 min) and machine-learning based ASPECTS evaluation (ICC = 0.24 for OTI < 100 min, ICC = 0.61 for OTI 100-200 min, ICC = 0.63 for OTI ≥ 200 min). The same applied to the interrater reliability. Collaterals were predictors of a favorable clinical outcome especially in hyperacute stroke with OTI < 100 min (collaterals: OR = 5.67 CI = 2.38-17.8, p < 0.001; ASPECTS: OR = 1.44, CI = 0.91-2.65, p = 0.15) while ASPECTS was in prolonged OTI ≥ 200 min (collaterals OR = 4.21,CI = 1.36-21.9, p = 0.03; ASPECTS: OR = 2.85, CI = 1.46-7.46, p = 0.01). CONCLUSION: The accuracy and reliability of NCCT-ASPECTS are time dependent for both human and machine-learning based evaluation, indicating reduced detectability of fast stroke progressors by NCCT. In hyperacute stroke, collateral status from CT-angiography may help for a better prognosis on clinical outcome and explain the occurrence of futile recanalization.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular , Isquemia Encefálica/terapia , Angiografía Cerebral/métodos , Angiografía por Tomografía Computarizada/métodos , Humanos , Aprendizaje Automático , Pronóstico , Reproducibilidad de los Resultados , Estudios Retrospectivos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/terapia , Tomografía Computarizada por Rayos X/métodos
12.
Schmerz ; 36(6): 422-428, 2022 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-34762202

RESUMEN

BACKGROUND: Cystic fibrosis (CF) is a rare genetic multisystemic disorder with progressive abdominal and pulmonary involvement. Pain is still an underestimated symptom in CF patients. METHODS: A comprehensive review of guidelines and scientific literature on the topic was performed and combined with findings from pain management in a young CF patient with progressive thoracic pain. RESULTS: German CF guidelines do not cover diagnosis and management of pain in these patients. Studies from Europe and the United States report interactions between intensity of pain and mortality in CF, but do not include data on the efficacy of pain management. These data and clinical observations of a CF patient with episodes of intense thoracic pain are used to illustrate the specific challenges in pain relief. CONCLUSION: Pain management in CF requires meticulous monitoring as well as an interdisciplinary approach and should be implemented in the German CF guidelines. The authors also want to suggest recommendations for the treatment of thoracic pain in CF. The range and severity of organ involvement complicates the use both of opioids and non-opioids. Especially opioid treatment carries the risk of hypoxia and opioid-induced constipation (OIC) and needs close medical supervision.


Asunto(s)
Fibrosis Quística , Humanos , Estados Unidos , Fibrosis Quística/complicaciones , Fibrosis Quística/diagnóstico , Fibrosis Quística/terapia , Manejo del Dolor , Analgésicos Opioides/efectos adversos , Estreñimiento , Dolor/tratamiento farmacológico
13.
Rev Sci Instrum ; 92(9): 093202, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34598519

RESUMEN

Cold atom experiments commonly use broad magnetic Feshbach resonances to manipulate the interaction between atoms. In order to induce quantum dynamics by a change in the interaction strength, rapid (∼µs) magnetic field changes over several tens of Gauss are required. Here, we present a compact design of a coil and its control circuit for a change in the magnetic field up to 36 G in 3 µs. The setup comprises two concentric solenoids with minimal space requirements, which can be readily added to existing apparatuses. This design makes the observation of non-equilibrium physics with broad Feshbach resonances accessible.

14.
Phys Rev Lett ; 126(13): 137201, 2021 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-33861132

RESUMEN

We present an experimental study of time refraction of spin waves (SWs) propagating in microscopic waveguides under the influence of time-varying magnetic fields. Using space- and time-resolved Brillouin light scattering microscopy, we demonstrate that the broken translational symmetry along the time coordinate results in a loss of energy conservation for SWs and thus allows for a broadband and controllable shift of the SW frequency. With an integrated design of SW waveguide and microscopic current line for the generation of strong, nanosecond-long, magnetic field pulses, a conversion efficiency up to 39% of the carrier SW frequency is achieved, significantly larger compared to photonic systems. Given the strength of the magnetic field pulses and its strong impact on the SW dispersion relation, the effect of time refraction can be quantified on a length scale comparable to the SW wavelength. Furthermore, we utilize time refraction to excite SW bursts with pulse durations in the nanosecond range and a frequency shift depending on the pulse polarity.

15.
Animal ; 15(3): 100155, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33573951

RESUMEN

The inclusion of corn-dried distillers' grains (DDG) could be an alternative supplement to increase animal performance, nitrogen efficiency usage (NEU), and decrease enteric methane (CH4) emissions. Our goal was to determine whether DDG could replace a traditional supplement (cottonseed meal) without affecting animal performance, N balance, and CH4 emissions. The experiment was conducted during the forage growing season (December to April), with 15 d adaptation, and a 112 d experimental period. The experimental design was completely randomized with four treatments: a mineral supplement (MS), cottonseed meal supplement (CS), 50% replacement of CS by DDG (50DDG), and 100% replacement of CS by DDG (100DDG). Cottonseed meal and DDG were used as protein supplement. A total of 12 paddocks, 3 per treatment, were used to measure forage mass: morphological and chemical composition of forage, forage allowance, and animal performance. Six animals per treatment were used to evaluate DM intake, digestibility, CH4 emissions, microbial protein production (MCP), and NEU of each treatment. Eighty-one Young Nellore bulls (48 testers, 12 per treatments and 33 adjusters) with initial BW of 255 ±â€¯5 kg (10-12 months old) were supplemented with each supplement type at a level of 0.3% of BW. Pasture management was continuous stocking with a variable stocking rate (put-and-take). Enteric CH4 was measured using the gas tracer technique. The MCP was quantified using purine derivatives and the NEU mass balance. No differences were found in nutrient intake (P > 0.228). Individual animal performance and gain per area were higher in the treatments with concentrates compared with that of MS; however, there was no difference among treatments CS, 50DDG, and 100DDG. The ADG was 0.83 for MS and 1.08 kg/animal/d when supplemented (P < 0.05). Gain per hectare was 709 kg/ha for MS and 915 kg/ha when supplemented with concentrates (P < 0.05). There was no difference in CH4 production among treatments that average 180 g/animal/d; however, CH4 per kg of gain was reduced with CS. The CH4 conversion factor averaged 5.91%. There was no difference in the synthesis of MCP and NEU. Corn DDG can replace 100% of cottonseed meal as a protein source for supplementation of young Nellore bulls grazing in tropical pastures without affecting animal performance, NEU, MCP, and CH4 emissions.


Asunto(s)
Alimentación Animal , Zea mays , Alimentación Animal/análisis , Animales , Bovinos , Dieta/veterinaria , Suplementos Dietéticos , Digestión , Masculino , Nitrógeno
16.
J Vet Cardiol ; 33: 1-5, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33221699

RESUMEN

Idiopathic dilated cardiomyopathy (DCM) is a common acquired cardiac disease in large breed dogs with a high prevalence in Doberman pinschers. It is characterized histologically by attenuated wavy fibers and fatty infiltration with degeneration. The phenotypic appearance of DCM includes ventricular dilation with systolic dysfunction and ventricular arrhythmias. These changes can be caused by other etiologies, including infectious, toxic, metabolic, and nutritional deficiencies. Chagas disease is the result of an infection with the protozoal parasite, Trypanosoma cruzi, transmitted by an insect vector. Histopathology of the myocardium is characterized by inflammation, fibrosis, and pseudocysts containing T. cruzi amastigotes. Differentiating idiopathic DCM from infectious myocarditis can be challenging when the clinical presentation and diagnostic test results are similar in affected dogs. We present thoracic radiographs, echocardiography, and post-mortem histopathology images obtained from two Doberman pinschers with similar signalment, clinical presentation, and electrocardiographic and echocardiographic appearance but with different appearing radiographs and different etiologies for their heart disease, one with idiopathic DCM and one with myocarditis attributed to Chagas disease, to highlight the value of considering alternative etiologies for DCM to guide additional clinical evaluation and owner counseling.


Asunto(s)
Cardiomiopatía Dilatada/veterinaria , Cardiomiopatía Chagásica/veterinaria , Enfermedades de los Perros/etiología , Animales , Cardiomiopatía Dilatada/diagnóstico por imagen , Cardiomiopatía Dilatada/etiología , Cardiomiopatía Dilatada/patología , Cardiomiopatía Chagásica/diagnóstico por imagen , Cardiomiopatía Chagásica/patología , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/parasitología , Enfermedades de los Perros/patología , Perros , Ecocardiografía/veterinaria , Electrocardiografía/veterinaria , Masculino , Tórax/diagnóstico por imagen , Trypanosoma cruzi/aislamiento & purificación
17.
J Phys Condens Matter ; 33(6): 065803, 2021 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-33091893

RESUMEN

We report broadband ferromagnetic resonance measurements of the in-plane magnetic field response of three- and four-fold symmetric vertices formed by non-contacting permalloy nano-ellipses together with extended lattices constructed from them. Complementing the experimental data with simulations, we are able to show that, as far as the most intense FMR responses are concerned, the spectra of vertices and lattices can largely be interpreted in terms of a superposition of the underlying hysteretic responses of the individual ellipses, as elemental building blocks of the system. This property suggest that it is possible to understand the orientation of the individual magnetic dipole moments in a dipole network in terms of dynamic measurements alone, thereby offering a powerful tool to analyze the alignment statistics in frustrated systems that are exposed to various magnetic histories.

18.
BMC Biol ; 18(1): 161, 2020 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-33158442

RESUMEN

BACKGROUND: The Wolbachia incompatible insect technique (IIT) shows promise as a method for eliminating populations of invasive mosquitoes such as Aedes aegypti (Linnaeus) (Diptera: Culicidae) and reducing the incidence of vector-borne diseases such as dengue, chikungunya and Zika. Successful implementation of this biological control strategy relies on high-fidelity separation of male from female insects in mass production systems for inundative release into landscapes. Processes for sex-separating mosquitoes are typically error-prone and laborious, and IIT programmes run the risk of releasing Wolbachia-infected females and replacing wild mosquito populations. RESULTS: We introduce a simple Markov population process model for studying mosquito populations subjected to a Wolbachia-IIT programme which exhibit an unstable equilibrium threshold. The model is used to study, in silico, scenarios that are likely to yield a successful elimination result. Our results suggest that elimination is best achieved by releasing males at rates that adapt to the ever-decreasing wild population, thus reducing the risk of releasing Wolbachia-infected females while reducing costs. CONCLUSIONS: While very high-fidelity sex separation is required to avoid establishment, release programmes tend to be robust to the release of a small number of Wolbachia-infected females. These findings will inform and enhance the next generation of Wolbachia-IIT population control strategies that are already showing great promise in field trials.


Asunto(s)
Aedes/microbiología , Control de Mosquitos/métodos , Mosquitos Vectores/microbiología , Wolbachia/fisiología , Animales , Femenino , Masculino , Cadenas de Markov , Modelos Biológicos , Dinámica Poblacional
19.
Phys Rev Lett ; 125(9): 097201, 2020 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-32915598

RESUMEN

Using first-principles transport calculations, we predict that the anisotropic magnetoresistance (AMR) of single-crystal Co_{x}Fe_{1-x} alloys is strongly dependent on the current orientation and alloy concentration. An intrinsic mechanism for AMR is found to arise from the band crossing due to magnetization-dependent symmetry protection. These special k points can be shifted towards or away from the Fermi energy by varying the alloy composition and hence the exchange splitting, thus allowing AMR tunability. The prediction is confirmed by delicate transport measurements, which further reveal a reciprocal relationship of the longitudinal and transverse resistivities along different crystal axes.

20.
Arq. bras. med. vet. zootec. (Online) ; 72(3): 754-760, May-June, 2020. ilus, tab
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1129169

RESUMEN

A captive 7-year-old male bush dog (Speothos venaticus) was diagnosed with lymphoma affecting the kidneys, adrenal glands, liver, and spleen. The animal developed renal failure and was euthanized due to poor prognosis. Grossly, both kidneys were enlarged with multiple nodules. Histologically, the neoplasm was an infiltrative and poorly demarcated round cell tumor. Two morphologically distinct cell populations were observed, smaller cells with a lymphocytic morphology, and another population of larger and pleomorphic cells. Most of the smaller cell population, approximately 40% of the population within the neoplasm, were CD3 positive. Neoplastic cells were CD45, CD11d, and granzime B positive, and negative for CD20, CD79a, PAX5, CD163, and myeloperoxidase. This is the first reported case of lymphoma in a bush dog. This report demonstrated the suitability of several cell surface markers for differential diagnosis of round cell tumors in this species.(AU)


Um cachorro-do-mato-vinagre (Speothos venaticus), de sete anos de idade, mantido em cativeiro, foi diagnosticado com linfoma que havia afetado os rins, as adrenais, o fígado e o baço. O animal desenvolveu insuficiência renal e foi submetido à eutanásia devido ao prognóstico desfavorável. Macroscopicamente, ambos os rins estavam aumentados de tamanho, com múltiplos nódulos. Histologicamente, a neoplasia era infiltrativa, pobremente delimitada e constituída por células redondas. Duas populações distintas foram observadas: células pequenas com morfologia linfocítica e células grandes e pleomórficas. A maior parte da população de células pequenas, correspondendo a aproximadamente 40% da população celular na neoplasia, foi positiva para CD3. As células neoplásicas foram positivas para CD45, CD11d e granzima B e negativas para CD20, CD79a, PAX5, CD163 e mieloperoxidase. Este é o primeiro caso de linfoma em um cachorro-do-mato-vinagre. Tal relado demonstra a utilidade de vários marcadores de superfície celular para o diagnóstico diferencial de tumores de células redondas nessa espécie.(AU)


Asunto(s)
Animales , Masculino , Perros , Extensión Extranodal , Linfoma/veterinaria , Inmunohistoquímica/veterinaria , Insuficiencia Renal/veterinaria , Animales Salvajes
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