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1.
Dev Biol ; 503: 25-42, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37573008

RESUMO

Craniofacial development is orchestrated by transcription factor-driven regulatory networks, epigenetic modifications, and signaling pathways. Signaling molecules and their receptors rely on endo-lysosomal trafficking to prevent accumulation on the plasma membrane. ESCRT (Endosomal Sorting Complexes Required for Transport) machinery is recruited to endosomal membranes enabling degradation of such endosomal cargoes. Studies in vitro and in invertebrate models established the requirements of the ESCRT machinery in membrane remodeling, endosomal trafficking, and lysosomal degradation of activated membrane receptors. However, investigations during vertebrate development have been scarce. By ENU-induced mutagenesis, we isolated a mouse line, Vps25ENU/ENU, carrying a hypomorphic allele of the ESCRT-II component Vps25, with craniofacial anomalies resembling features of human congenital syndromes. Here, we assessed the spatiotemporal dynamics of Vps25 and additional ESCRT-encoding genes during murine development. We show that these genes are ubiquitously expressed although enriched in discrete domains of the craniofacial complex, heart, and limbs. ESCRT-encoding genes, including Vps25, are expressed in both cranial neural crest-derived mesenchyme and epithelium. Unlike constitutive ESCRT mutants, Vps25ENU/ENU embryos display late lethality. They exhibit hypoplastic lower jaw, stunted snout, dysmorphic ear pinnae, and secondary palate clefting. Thus, we provide the first evidence for critical roles of ESCRT-II in craniofacial morphogenesis and report perturbation of NOTCH signaling in craniofacial domains of Vps25ENU/ENU embryos. Given the known roles of NOTCH signaling in the developing cranium, and notably the lower jaw, we propose that the NOTCH pathway partly mediates the craniofacial defects of Vps25ENU/ENU mouse embryos.


Assuntos
Proteínas de Transporte , Complexos Endossomais de Distribuição Requeridos para Transporte , Animais , Humanos , Camundongos , Transporte Proteico/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Proteínas de Transporte/metabolismo , Transdução de Sinais , Morfogênese , Endossomos/metabolismo
2.
Pract Neurol ; 21(3): 228-230, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33850031

RESUMO

A 73-year-old man presented with unsteadiness and general malaise and later had problems with cognition. This was initially diagnosed as benign paroxysmal positional vertigo, but he was later found to have giant cell arteritis. Neurologists and physicians should be aware that giant cell arteritis can present with encephalopathy rather than the more typical features of headache, jaw pain and visual disturbance.


Assuntos
Arterite de Células Gigantes , Idoso , Arterite de Células Gigantes/complicações , Arterite de Células Gigantes/diagnóstico , Cefaleia/etiologia , Humanos , Masculino , Transtornos da Visão/etiologia
3.
Blood ; 126(14): 1638-9, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26429964

RESUMO

In this issue of Blood, Bernard et al provide evidence that ibrutinib, the orally administered inhibitor of Bruton tyrosine kinase (BTK), crosses the blood-brain barrier and has activity against mantle cell lymphoma (MCL) in the central nervous system (CNS).


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Linfoma de Célula do Manto/tratamento farmacológico , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Feminino , Humanos , Masculino
4.
Environ Microbiol Rep ; 16(4): e70001, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39189590

RESUMO

To characterize the source and effects of bacterial communities on corrosion of intertidal structures, three different UK coastal sites were sampled for corrosion materials, sediment and seawater. Chemical analyses indicate the activity of sulfate-reducing microbes (SRBs) at 2 sites (Shoreham and Newhaven), but not at the third (Southend-on-Sea). Microbial communities in the deep sediment and corrosion samples are similar. The phylum Proteobacteria is dominant (40.4% of the total ASV), followed by Campilobacterota (11.3%), Desulfobacterota and Firmicutes (4%-5%). At lower taxonomic levels, corrosion causing bacteria, such as Shewanella sp. (6%), Colwellia sp. (7%) and Mariprofundus sp. (1%), are present. At Southend-on-sea, the relative abundance of Campilobacterota is higher compared to the other two sites. The mechanism of action of microorganisms at Shoreham and Newhaven involves biogenic sulfuric acid corrosion of iron by the combined action of SRBs and sulfur-oxidizing microbes. However, at Southend-on-sea, sulfur compounds are not implicated in corrosion, but SRBs and other electroactive microbes may play a role in which cathodic reactions (electrical MIC) and microbial enzymes (chemical MIC) are involved. To contribute to diagnosis of accelerated intertidal corrosion types, we developed a rapid identification method for SRBs using quantitative polymerase chain reaction high-resolution melt curve analysis of the dsrB gene.


Assuntos
Bactérias , Sequenciamento de Nucleotídeos em Larga Escala , Água do Mar , Aço , Corrosão , Aço/química , Água do Mar/microbiologia , Bactérias/genética , Bactérias/classificação , Bactérias/isolamento & purificação , Sedimentos Geológicos/microbiologia , Microbiota/genética , Filogenia , Reino Unido , RNA Ribossômico 16S/genética
5.
R Soc Open Sci ; 8(8): 202013, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34386244

RESUMO

Conodont elements, microfossil remains of extinct primitive vertebrates, are commonly exploited as mineral archives of ocean chemistry, yielding fundamental insights into the palaeotemperature and chemical composition of past oceans. Geochemical assays have been traditionally focused on the so-called lamellar and white matter crown tissues; however, the porosity and crystallographic nature of the white matter and its inferred permeability are disputed, raising concerns over its suitability as a geochemical archive. Here, we constrain the characteristics of this tissue and address conflicting interpretations using ptychographic X-ray-computed tomography (PXCT), pore network analysis, synchrotron radiation X-ray tomographic microscopy (srXTM) and electron back-scatter diffraction (EBSD). PXCT and pore network analyses based on these data reveal that while white matter is extremely porous, the pores are unconnected, rendering this tissue closed to postmortem fluid percolation. EBSD analyses demonstrate that white matter is crystalline and comprised of a single crystal typically tens of micrometres in dimensions. Combined with evidence that conodont elements grow episodically, these data suggest that white matter, which comprises the denticles of conodont elements, grows syntactically, indicating that individual crystals are time heterogeneous. Together these data provide support for the interpretation of conodont white matter as a closed geochemical system and, therefore, its utility of the conodont fossil record as a historical archive of Palaeozoic and Early Mesozoic ocean chemistry.

6.
EClinicalMedicine ; 19: 100229, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32140667

RESUMO

BACKGROUND: UK and European guidelines recommend HIV testing in general practice. We report on the implementation of the Rapid HIV Assessment trial (RHIVA2) promoting HIV screening in general practice into routine care. METHODS: Interrupted time-series, difference-in-difference analysis and Pearson-correlation on three cohorts comprising 42 general practices in City & Hackney (London, UK); covering three periods: pre-trial (2009-2010), trial (2010-2012) and implementation (2012-2014). Cohorts comprised practices receiving: "trial intervention" only (n = 19), "implementation intervention" only (n = 13); and neither ("comparator") (n = 10). Primary outcomes were HIV testing and diagnosis rates per 1000 people and CD4 at diagnosis. FINDINGS: Overall, 55,443 people were tested (including 38,326 among these cohorts), and 101 people were newly diagnosed HIV positive (including 65 among these cohorts) including 74 (73%) heterosexuals and 69 (68%) people of black African/Caribbean background; with mean CD4 count at diagnosis 357 (SD=237). Among implementation intervention practices, testing rate increased by 85% (from 1·798 (95%CI=(1·657,1·938) at baseline to 3·081 (95%CI=(2·865,3·306); p = 0·0000), diagnosis rate increased by 34% (from 0·0026 (95%CI=(0·0004,0·0037)) to 0·0035 (95%CI=(0·0007,0·0062); p = 0·736), and mean CD4 count at diagnosis increased by 55% (from 273 (SD=372) to 425 (SD=274) cells per µL; p = 0·433). Implementation intervention and trial intervention practices achieved similar testing rates (3·764 vs. 3·081; 6% difference; 95% CI=(-5%,18%); p = 0·358), diagnosis rates (0·0035 vs. 0·0081; -13% difference; 95%CI=(-77%,244%; p = 0·837), and mean CD4 count (425 (SD=274) vs. 351 (SD=257); 69% increase; 95% CI=(-61%,249%); p = 0·359). HIV testing was positively correlated with diagnosis (r = 0·114 (95% CI=[0·074,0·163])), and diagnosis with CD4 count at diagnosis (r = 0·011 (95% CI=[-0·177,0·218])). INTERPRETATION: Implementation of the RHIVA programme promoting nurse-led HIV screening into routine practice in inner-city practices with high HIV prevalence increased HIV testing, and may be associated with increased and earlier diagnosis. HIV screening in primary care should be considered a key strategy to reduce undiagnosed infection particularly among high risk persons not attending sexual health services. FUNDING: National Institute for Health Research ARC North Thames, and Barts and The London School of Medicine and Dentistry.

7.
Arch Ophthalmol ; 124(8): 1171-4, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16908820

RESUMO

Achieving secure bony fixation of medial canthus is a challenge. We used a resorbable poly-L-lactic acid-polyglycolic acid screw (LactoSorb office fixation kit) in 5 cases: 2 with traumatic medial canthal dystopia, 1 with scleroderma and orbital fat atrophy causing malapposition of the medial canthus to globe, and 2 with invasive medial canthal tumors necessitating subtotal medial orbital exenteration. The resorbable screw with preplaced suture was drilled into the medial orbital wall, using a handheld self-drilling tap. The preplaced suture was used to anchor the medial canthus. We achieved satisfactory canthal position in all 5 cases. There were no complications in 4 cases during a mean +/- SD follow-up of 11.3 +/- 6 months; however, the scleroderma case developed wound dehiscence 6 weeks after surgery. The LactoSorb kit is a safe and effective technique to achieve bony medial canthal fixation in carefully selected cases.


Assuntos
Implantes Absorvíveis , Materiais Biocompatíveis , Doenças Palpebrais/cirurgia , Pálpebras/cirurgia , Ácido Láctico , Procedimentos Cirúrgicos Oftalmológicos , Órbita/cirurgia , Ácido Poliglicólico , Polímeros , Adulto , Idoso , Parafusos Ósseos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Técnicas de Sutura
8.
Zootaxa ; 4139(4): 451-80, 2016 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-27470819

RESUMO

During a project of the Luxembourg National Museum of Natural History the parasitism of water mites dwelling a small stream (Lurenzgriecht) in the southern part of the country (Gutland) was investigated. The first step of the project was to clarify the taxonomy of the larvae of all stream-dwelling species. For that reason emergence traps were installed in the stream during 2002 and emptied every 14 days to obtain parasitized hosts. Additionally, rearing experiments were implemented in the laboratory to produce larvae of well-defined species/mothers but only with partly success. The stream has a well-known water mite inventory of 22 species, almost equally composed of true benthic species and species strongly adapted to hyporheic interstitial. The larvae of five species (Torrenticola elliptica, Atractides pumilus, Feltria motasi, Ljania macilenta, Neoacarus hibernicus) were described here as new to science. Due to the poor quality and availability of former descriptions a re-description was made for another species living in the stream (Sperchon denticulatus-gr.) and, additionally, for Hygrobates fluviatilis, a common stream-dwelling species of the area. The larvae of nine species of the Lurenzgriecht had already been sufficiently described for identification purposes (Protzia eximia, Sperchonopsis verrucosa, Sperchon clupeifer, S. thienemanni, Lebertia glabra, Atractides fonticolus, Feltria rouxi, Ljania bipapillata, Aturus fontinalis). The larvae of some other species (Aturus crinitus, Kongsbergia spp., Stygohydracarus subterraneus, Arrenurus haplurus) could neither be reared in the lab nor attributed to species for taxonomic reasons. With the exception of Kongsbergia spp. (no known larva of the genus worldwide) and Aturus crinitus (a rare species in the Lurenzgriecht) an identification key was compiled for the larvae of all known species of the stream using the new descriptions and all available information on the other ones.


Assuntos
Ácaros/anatomia & histologia , Ácaros/crescimento & desenvolvimento , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Ecossistema , Feminino , Larva/anatomia & histologia , Larva/classificação , Larva/crescimento & desenvolvimento , Masculino , Ácaros/classificação , Tamanho do Órgão , Rios/parasitologia
9.
Front Vet Sci ; 3: 85, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27713881

RESUMO

Small-scale pig producers are believed to pose higher biosecurity risks for the introduction and spread of exotic diseases than commercial pig producers. However, the magnitude of these risks is poorly understood. This study is a comparative assessment of the risk of introduction and spread of foot-and-mouth disease (FMD) through different sectors of the pig industry: (1) large-scale pig producers; (2) small-scale producers (<100 sows) selling at saleyards and abattoirs; and (3) small-scale producers selling through informal means. An exposure and consequence assessments were conducted using the World Organization for Animal Health methodology for risk analysis, assuming FMD virus was introduced into Australia through illegal importation of infected meat. A quantitative assessment, using scenario trees and Monte Carlo stochastic simulation, was used to calculate the probabilities of exposure and spread. Input data for these assessments were obtained from a series of data gathering exercises among pig producers, industry statistics, and literature. Findings of this study suggest there is an Extremely low probability of exposure (8.69 × 10-6 to 3.81 × 10-5) for the three sectors of the pig industry, with exposure through direct swill feeding being 10-100 times more likely to occur than through contact with infected feral pigs. Spread of FMD from the index farm is most likely to occur through movement of contaminated fomites, pigs, and ruminants. The virus is more likely to spread from small-scale piggeries selling at saleyards and abattoirs than from other piggeries. The most influential factors on the spread of FMD from the index farm is the ability of the farmer to detect FMD, the probability of FMD spread through contaminated fomites and the presence of ruminants on the farm. Although small-scale producers selling informally move animals less frequently and do not use external staff, movement of pigs to non-commercial pathways could jeopardize animal traceability in the event of a disease outbreak. This study suggests that producers' awareness on and engagement with legislative and industry requirements in relation to biosecurity and emergency animal disease management needs to be improved. Results from this study could be used by decision-makers to prioritize resource allocation for improving animal biosecurity in the pig industry.

10.
Cancer Discov ; 4(9): 1022-35, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25082755

RESUMO

UNLABELLED: Despite the unprecedented clinical activity of the Bruton tyrosine kinase (BTK) inhibitor ibrutinib in mantle cell lymphoma (MCL), acquired resistance is common. By longitudinal integrative whole-exome and whole-transcriptome sequencing and targeted sequencing, we identified the first relapse-specific C481S mutation at the ibrutinib binding site of BTK in MCL cells at progression following a durable response. This mutation enhanced BTK and AKT activation and tissue-specific proliferation of resistant MCL cells driven by CDK4 activation. It was absent, however, in patients with primary resistance or progression following transient response to ibrutinib, suggesting alternative mechanisms of resistance. Through synergistic induction of PIK3IP1 and inhibition of PI3K-AKT activation, prolonged early G1 arrest induced by PD 0332991 (palbociclib) inhibition of CDK4 sensitized resistant lymphoma cells to ibrutinib killing when BTK was unmutated, and to PI3K inhibitors independent of C481S mutation. These data identify a genomic basis for acquired ibrutinib resistance in MCL and suggest a strategy to override both primary and acquired ibrutinib resistance. SIGNIFICANCE: We have discovered the first relapse-specific BTK mutation in patients with MCL with acquired resistance, but not primary resistance, to ibrutinib, and demonstrated a rationale for targeting the proliferative resistant MCL cells by inhibiting CDK4 and the cell cycle in combination with ibrutinib in the presence of BTK(WT) or a PI3K inhibitor independent of BTK mutation. As drug resistance remains a major challenge and CDK4 and PI3K are dysregulated at a high frequency in human cancers, targeting CDK4 in genome-based combination therapy represents a novel approach to lymphoma and cancer therapy. Cancer Discov; 4(9); 1022-35. ©2014 AACR. This article is highlighted in the In This Issue feature, p. 973.


Assuntos
Ciclo Celular/genética , Genômica , Linfoma de Célula do Manto/genética , Linfoma de Célula do Manto/metabolismo , Mutação , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Tirosina Quinases/genética , Adenina/análogos & derivados , Tirosina Quinase da Agamaglobulinemia , Substituição de Aminoácidos , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Análise Mutacional de DNA , Resistencia a Medicamentos Antineoplásicos/genética , Sinergismo Farmacológico , Ativação Enzimática , Humanos , Linfoma de Célula do Manto/tratamento farmacológico , Linfoma de Célula do Manto/patologia , NF-kappa B/metabolismo , Recidiva Local de Neoplasia , Nitratos/farmacologia , Nitratos/uso terapêutico , Piperidinas , Polietilenoglicóis/farmacologia , Polietilenoglicóis/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcr/metabolismo , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Transdução de Sinais , Resultado do Tratamento
11.
Pharm Dev Technol ; 10(4): 451-60, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16370174

RESUMO

Micronization is a commonly used enabling technology to improve the bioavailability of compounds where absorption is dissolution rate limited. However, decreasing particle size often results in increased Van der Waals' interactions and electrostatic attraction between particles. This causes agglomeration of particles, thereby compromising the increase in surface area gained by micronization. Comicronization with excipients has been reported to offer significant advantages over neat micronization. The present work describes the comicronization of a model compound CI-1040 at a high drug load that shows an increase in the dissolution rate and bioavailability in male Wistar rats. Physicochemical characterization of the comicronized and neat micronized material is presented to help explain the in-vitro and in-vivo data.


Assuntos
Benzamidas/química , Benzamidas/farmacocinética , Celulose/química , Excipientes/química , Tecnologia Farmacêutica/métodos , Animais , Disponibilidade Biológica , Masculino , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Ratos , Ratos Wistar , Solubilidade , Propriedades de Superfície , Difração de Raios X
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