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1.
Nature ; 602(7897): 403-407, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35173340

RESUMO

In the widely accepted 'unified model'1 solution of the classification puzzle of active galactic nuclei, the orientation of a dusty accretion torus around the central black hole dominates their appearance. In 'type-1' systems, the bright nucleus is visible at the centre of a face-on torus. In 'type-2' systems the thick, nearly edge-on torus hides the central engine. Later studies suggested evolutionary effects2 and added dusty clumps and polar winds3 but left the basic picture intact. However, recent high-resolution images4 of the archetypal type-2 galaxy NGC 10685,6, suggested a more radical revision. The images displayed a ring-like emission feature that was proposed to be hot dust surrounding the black hole at the radius where the radiation from the central engine evaporates the dust. That ring is too thin and too far tilted from edge-on to hide the central engine, and ad hoc foreground extinction is needed to explain the type-2 classification. These images quickly generated reinterpretations of the dichotomy between types 1 and 27,8. Here we present new multi-band mid-infrared images of NGC 1068 that detail the dust temperature distribution and reaffirm the original model. Combined with radio data (J.F.G. and C.M.V.I., manuscript in preparation), our maps locate the central engine that is below the previously reported ring and obscured by a thick, nearly edge-on disk, as predicted by the unified model. We also identify emission from polar flows and absorbing dust that is mineralogically distinct from that towards the Milky Way centre.

2.
Part Fibre Toxicol ; 15(1): 9, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29382351

RESUMO

BACKGROUND: The use of engineered nanoparticles (NP) is widespread and still increasing. There is a great need to assess their safety. Newly engineered NP enter the market in a large variety; therefore safety evaluation should preferably be in a high-throughput fashion. In vitro screening is suitable for this purpose. TiO 2 NP exist in a large variety (crystal structure, coating and size), but information on their relative toxicities is scarce. TiO 2 NP may be inhaled by workers in e.g. paint production and application. In mice, inhalation of TiO 2 NP increases allergic reactions. Dendritic cells (DC) form an important part of the lung immune system, and are essential in adjuvant activity. The present study aimed to establish the effect of a variety of TiO 2 NP on DC maturation in vitro. Two NP of different crystal structure but similar in size, uncoated and from the same supplier, were evaluated for their adjuvant activity in vivo. METHODS: Immature DC were differentiated in vitro from human peripheral blood monocytes. Exposure effects of a series of fourteen TiO 2 NP on cell viability, CD83 and CD86 expression, and IL-12p40 and TNF-α production were measured. BALB/c mice were intranasally sensitized with ovalbumin (OVA) alone, OVA plus anatase TiO 2 NP, OVA plus rutile TiO 2 NP, and OVA plus Carbon Black (CB; positive control). The mice were intranasally challenged with OVA. OVA-specific IgE and IgG1 in serum, cellular inflammation in bronchoalveolar lavage fluid (BALF) and IL-4 and IL-5 production in draining bronchial lymph nodes were evaluated. RESULTS: All NP dispersions contained NP aggregates. The anatase NP and anatase/rutile mixture NP induced a higher CD83 and CD86 expression and a higher IL-12p40 production in vitro than the rutile NP (including coated rutile NP and a rutile NP of a 10-fold larger primary diameter). OVA-specific serum IgE and IgG1 were increased by anatase NP, rutile NP, and CB, in the order rutile

Assuntos
Células Dendríticas/efeitos dos fármacos , Imunidade Celular/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Nanopartículas/toxicidade , Titânio/toxicidade , Animais , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Cristalização , Células Dendríticas/imunologia , Humanos , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Interleucina-4/imunologia , Interleucina-5/imunologia , Pulmão/imunologia , Camundongos Endogâmicos BALB C , Nanopartículas/química , Tamanho da Partícula , Propriedades de Superfície , Titânio/química
3.
Int J Surg Protoc ; 28(1): 31-36, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38433866

RESUMO

Background: The aim of this study is to prospectively evaluate the new minimal invasive (MINE) browlift technique with possibly superior results and minimal visible scarring. Study design: A prospective observational study will be performed on all available data from patients who will undergo a browlift procedure in the HMC from 1 June 2021 till 31 May 2024. Our goal is to include at least 50 patients. Inclusion criteria are: patients with medical (i.e. brow ptosis and facial paralysis) or cosmetic indication, patients with sufficient understanding of the Dutch or English language and willingness to participate in extra study specific follow-up moments and filling in of questionnaires. Exclusion criteria are: less than 18 years of age and patients with previous brow or eyelid surgery. Patients will be photographed preoperatively and postoperatively using the VECTRA camera. Outcome measurements: Scarring after procedure; functionality of eyebrow movement; amount of correction in brow ptosis, measured in VECTRA; longevity of procedure in months; aesthetic result as assessed by questionnaires and adverse effects of procedure will be measured. Ethics and dissemination: The database management software 'Castor' will be used to store and collect the data from the questionnaire. The Medical Research Ethics Committee found this study not eligible to be submitted to the Dutch Medical Research Involving Human Subjects Acts (WMO). Written consent will be obtained from all patients.

4.
BMC Genomics ; 12: 510, 2011 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-22004469

RESUMO

BACKGROUND: RNAi technology by feeding of E. coli containing dsRNA in C. elegans has significantly contributed to further our understanding of many different fields, including genetics, molecular biology, developmental biology and functional genomics. Most of this research has been carried out in a single genotype or genetic background. However, RNAi effects in one genotype do not reveal the allelic effects that segregate in natural populations and contribute to phenotypic variation. RESULTS: Here we present a method that allows for rapidly comparing RNAi effects among diverse genotypes at an improved high throughput rate. It is based on assessing the fitness of a population of worms by measuring the rate at which E. coli is consumed. Critically, we demonstrate the analytical power of this method by QTL mapping the loss of RNAi sensitivity (in the germline) in a recombinant inbred population derived from a cross between Bristol and a natural isolate from Hawaii. Hawaii has lost RNAi sensitivity in the germline. We found that polymorphisms in ppw-1 contribute to this loss of RNAi sensitivity, but that other loci are also likely to be important. CONCLUSIONS: In summary, we have established a fast method that improves the throughput of RNAi in liquid, that generates quantitative data, that is easy to implement in most laboratories, and importantly that enables QTL mapping using RNAi.


Assuntos
Caenorhabditis elegans/genética , Interferência de RNA , Animais , Proteínas de Caenorhabditis elegans/antagonistas & inibidores , Proteínas de Caenorhabditis elegans/genética , Genótipo , Locos de Características Quantitativas
5.
Rev Med Interne ; 42(11): 781-788, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34144842

RESUMO

Formerly called normal pressure hydrocephalus, communicating chronic hydrocephalus (CCH) is a condition affecting 0.1 to 0.5% of patients over 60years of age. The pathophysiology of this disease is poorly understood, but a defect in cerebrospinal fluid (CSF) resorption appears to be commonly defined as the cause of the neurological disorders. The last important discovery is the description of the glymphatic system and its implication in CCH and CSF resorption. Comorbidities (Alzheimer's disease, microangiopathy, parkinsonism) are very frequent, and involve a diagnostic challenge. The clinical presentation is based on the Hakim and Adams triad, comprising gait disorders, mainly impairing walking, cognitive disorders, affecting executive functions, episodic memory, visuospatial cognition, and sphincter disorders as urinary incontinence (detrusor hyperactivity). The diagnosis is suspected through a set of arguments, combining the clinical presentation, the radiological data of the magnetic resonance imaging (MRI) showing a ventriculomegaly associated with signs of transependymomous resorption of the CSF and disappearance of the cortical sulci, and the clinical response to the depletion of CSF. In the presence of all these elements, or a strong clinical suspicion, the standard treatment will be of a permanent CSF shunt, using a ventriculoatrial or ventriculoperitoneal shunt. The effectiveness of this treatment defines the diagnosis. The clinical improvement is better when treatment occurs early after the onset of the disorders, reaching 75 to 90% of motor improvement.


Assuntos
Doença de Alzheimer , Hidrocefalia de Pressão Normal , Derivações do Líquido Cefalorraquidiano , Humanos , Hidrocefalia de Pressão Normal/diagnóstico , Hidrocefalia de Pressão Normal/epidemiologia , Imageamento por Ressonância Magnética , Derivação Ventriculoperitoneal
6.
Microorganisms ; 9(2)2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33672221

RESUMO

Using 642 forest plots from three regions in Germany, we analyzed the direct and indirect effects of forest management intensity and of environmental variables on lichen functional diversity (FDis). Environmental stand variables were affected by management intensity and acted as an environmental filter: summing direct and indirect effects resulted in a negative total effect of conifer cover on FDis, and a positive total effect of deadwood cover and standing tree biomass. Management intensity had a direct positive effect on FDis, which was compensated by an indirect negative effect via reduced standing tree biomass and lichen species richness, resulting in a negative total effect on FDis and the FDis of adaptation-related traits (FDisAd). This indicates environmental filtering of management and stronger niche partitioning at a lower intensity. In contrast, management intensity had a positive total effect on the FDis of reproduction-, dispersal- and establishment-related traits (FDisRe), mainly because of the direct negative effect of species richness, indicating functional over-redundancy, i.e., most species cluster into a few over-represented functional entities. Our findings have important implications for forest management: high lichen functional diversity can be conserved by promoting old, site-typical deciduous forests with a high richness of woody species and large deadwood quantity.

7.
Surg Obes Relat Dis ; 16(11): 1673-1682, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32859526

RESUMO

BACKGROUND: Despite the publication of the American Society for Metabolic and Bariatric Surgery (ASMBS) Outcome Reporting Standards in 2015, there is still a great variety in definitions used for reporting remission of co-morbidities after bariatric surgery. This hampers meaningful comparison of results. OBJECTIVE: To assess compliance with the ASMBS standards in current literature, and to evaluate use of the standards by applying them in a report on the outcomes of 5 co-morbidities after bariatric surgery. SETTING: Two clinics of the Dutch Obesity Clinic, location Den Haag and Velp, and three affiliated hospitals: Haaglanden Medical Center in Den Haag, Groene Hart Hospital in Gouda, and Vitalys Clinic in Velp. METHODS: A systematic search in PubMed was conducted to identify studies using the ASMBS standards. Besides, the standards were applied to a cohort of patients who underwent a primary bariatric procedure between November 2016 and June 2017. Outcomes of co-morbidities were determined at 6 and 12 months after surgery. RESULTS: Ten previous studies applying ASMBS definitions were identified by the search, including 6 studies using portions of the definitions, and 4 using complete definitions for 3 co-morbidities or in a small population. In this study, the standards were applied to 1064 patients, of whom 796 patients (75%) underwent Roux-en-Y gastric bypass and 268 patients (25%) underwent sleeve gastrectomy. At 12 months, complete remission of diabetes (glycosylated hemoglobin <6%, off medication) was reached in 63%, partial remission (glycosylated hemoglobin 6%-6.4%, off medication) in 7%, and improvement in 28% of patients (n = 232/248, 94%). Complete remission of hypertension (normotensive, off medication) was noted in 8%, partial remission (prehypertensive, off medication) in 23% and improvement in 63% (n = 397/412, 96%). Remission rate for dyslipidemia (normal nonhigh-density lipoprotein, off medication) was 57% and improvement rate was 19% (n = 129/133, 97%). Resolution of gastroesophageal reflux disease (no symptoms, off medication) was observed in 54% (n = 265/265). Obstructive sleep apnea syndrome improved in 90% (n = 157/169, 93%). CONCLUSIONS: Compliance with the ASMBS standards is low, despite ease of use. Standardized definitions provided by the ASMBS guideline could be used in future research to enable comparison of outcomes of different studies and surgical procedures.


Assuntos
Cirurgia Bariátrica , Derivação Gástrica , Laparoscopia , Obesidade Mórbida , Comorbidade , Gastrectomia , Humanos , Morbidade , Obesidade Mórbida/cirurgia , Padrões de Referência , Estudos Retrospectivos , Resultado do Tratamento , Redução de Peso
8.
PhytoKeys ; 135: 11-20, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31723332

RESUMO

In 1902, the nationwide citizen science project, known as FLORIVON, for mapping the flora of the Netherlands was launched, resulting in the publication of a complete flora atlas in 1980. Until 2004, the atlas dataset of the fieldwork between 1902 and 1950 had only been partly digitised and observations were aggregated and anonymised. Between 2001 and 2018, the dataset has been entirely digitised from the original field forms, including notes on non-native taxa. This paper presents key characteristics and figures of the dataset and provides an overview of the historical survey project, the digitisation process and subsequent validation of the data. The dataset is currently curated in the National Database Flora and Fauna and published in GBIF.

9.
Environ Pollut ; 146(2): 375-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16714078

RESUMO

Decreasing local ammonia air concentrations in a moderately polluted area in The Netherlands were accompanied by a rapid increase in nitrogen-sensitive species (acidophytes) and a decline of nitrogen-tolerant macrolichens (nitrophytes). This paper presents data on the relationship between nitrophyte abundance and species abundance for three ecological groups of epiphytic lichens: nitrophytes (positively correlated with ammonia), acidophytes (negatively correlated) and neutrophytes (which have an optimum at medium concentrations) and suggests ammonia dependent optimum curves for these groups. In this study neutrophytes were found to die-off massively at sites with a decrease of the ammonia air concentration over the period 1996-2003.


Assuntos
Poluentes Atmosféricos/toxicidade , Amônia/toxicidade , Líquens/efeitos dos fármacos , Poluentes Atmosféricos/análise , Amônia/análise , Biodiversidade , Ecossistema , Monitoramento Ambiental/métodos , Líquens/química , Países Baixos
10.
J Radiol ; 86(6 Pt 2): 733-46; quiz 746-7, 2005 Jun.
Artigo em Francês | MEDLINE | ID: mdl-16142068

RESUMO

Acute pancreatitis usually is a benign disease. However it can sometimes be severe with a 5% mortality. CT is the imaging technique of choice and should be performed in all cases. When clinical symptoms and laboratory findings are typical, the role of CT is to detect complications. In those cases, CT is ideally performed 72 hours after the beginning of symptoms. In other cases, CT can be performed earlier. The main usefulness of CT is to detect complications: necrosis, fluid collections and vascular involvement. Non-invasive imaging techniques, including US, are poorly sensitive for diagnosis of biliary pancreatitis.


Assuntos
Diagnóstico por Imagem , Pancreatite/diagnóstico , Doença Aguda , Diagnóstico Diferencial , Exsudatos e Transudatos , Cálculos Biliares/diagnóstico , Humanos , Litíase/diagnóstico , Imageamento por Ressonância Magnética , Necrose , Pâncreas/irrigação sanguínea , Neoplasias Pancreáticas/diagnóstico , Pancreatite/diagnóstico por imagem , Infarto do Baço/diagnóstico , Tomografia Computadorizada por Raios X , Ultrassonografia , Doenças Vasculares/diagnóstico
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