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1.
Annu Rev Biochem ; 81: 795-822, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22482909

RESUMO

Is it possible to meaningfully comprehend the diversity of the viral world? We propose that it is. This is based on the observation that, although there is immense genomic variation, every infective virion is restricted by strict constraints in structure space (i.e., there are a limited number of ways to fold a protein chain, and only a small subset of these have the potential to construct a virion, the hallmark of a virus). We have previously suggested the use of structure for the higher-order classification of viruses, where genomic similarities are no longer observable. Here, we summarize the arguments behind this proposal, describe the current status of structural work, highlighting its power to infer common ancestry, and discuss the limitations and obstacles ahead of us. We also reflect on the future opportunities for a more concerted effort to provide high-throughput methods to facilitate the large-scale sampling of the virosphere.


Assuntos
Fenômenos Fisiológicos Virais , Vírus/classificação , Animais , Genoma Viral , Humanos , Células Procarióticas/virologia , Vírion/fisiologia , Viroses/virologia , Vírus/genética , Vírus/metabolismo
2.
PLoS Biol ; 21(2): e3001922, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36780432

RESUMO

A universal taxonomy of viruses is essential for a comprehensive view of the virus world and for communicating the complicated evolutionary relationships among viruses. However, there are major differences in the conceptualisation and approaches to virus classification and nomenclature among virologists, clinicians, agronomists, and other interested parties. Here, we provide recommendations to guide the construction of a coherent and comprehensive virus taxonomy, based on expert scientific consensus. Firstly, assignments of viruses should be congruent with the best attainable reconstruction of their evolutionary histories, i.e., taxa should be monophyletic. This fundamental principle for classification of viruses is currently included in the International Committee on Taxonomy of Viruses (ICTV) code only for the rank of species. Secondly, phenotypic and ecological properties of viruses may inform, but not override, evolutionary relatedness in the placement of ranks. Thirdly, alternative classifications that consider phenotypic attributes, such as being vector-borne (e.g., "arboviruses"), infecting a certain type of host (e.g., "mycoviruses," "bacteriophages") or displaying specific pathogenicity (e.g., "human immunodeficiency viruses"), may serve important clinical and regulatory purposes but often create polyphyletic categories that do not reflect evolutionary relationships. Nevertheless, such classifications ought to be maintained if they serve the needs of specific communities or play a practical clinical or regulatory role. However, they should not be considered or called taxonomies. Finally, while an evolution-based framework enables viruses discovered by metagenomics to be incorporated into the ICTV taxonomy, there are essential requirements for quality control of the sequence data used for these assignments. Combined, these four principles will enable future development and expansion of virus taxonomy as the true evolutionary diversity of viruses becomes apparent.


Assuntos
Bacteriófagos , Vírus , Humanos , Metagenômica , Filogenia , Vírus/genética
3.
Mol Psychiatry ; 28(5): 2018-2029, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36732587

RESUMO

Seven Tesla magnetic resonance spectroscopy (7T MRS) offers a precise measurement of metabolic levels in the human brain via a non-invasive approach. Studying longitudinal changes in brain metabolites could help evaluate the characteristics of disease over time. This approach may also shed light on how the age of study participants and duration of illness may influence these metabolites. This study used 7T MRS to investigate longitudinal patterns of brain metabolites in young adulthood in both healthy controls and patients. A four-year longitudinal cohort with 38 patients with first episode psychosis (onset within 2 years) and 48 healthy controls was used to examine 10 brain metabolites in 5 brain regions associated with the pathophysiology of psychosis in a comprehensive manner. Both patients and controls were found to have significant longitudinal reductions in glutamate in the anterior cingulate cortex (ACC). Only patients were found to have a significant decrease over time in γ-aminobutyric acid, N-acetyl aspartate, myo-inositol, total choline, and total creatine in the ACC. Together we highlight the ACC with dynamic changes in several metabolites in early-stage psychosis, in contrast to the other 4 brain regions that also are known to play roles in psychosis. Meanwhile, glutathione was uniquely found to have a near zero annual percentage change in both patients and controls in all 5 brain regions during a four-year follow-up in young adulthood. Given that a reduction of the glutathione in the ACC has been reported as a feature of treatment-refractory psychosis, this observation further supports the potential of glutathione as a biomarker for this subset of patients with psychosis.


Assuntos
Glutamina , Transtornos Psicóticos , Humanos , Adulto Jovem , Adulto , Glutamina/metabolismo , Transtornos Psicóticos/metabolismo , Encéfalo/metabolismo , Ácido Glutâmico/metabolismo , Giro do Cíngulo/metabolismo , Ácido Aspártico/metabolismo , Glutationa/metabolismo
4.
J Psychiatry Neurosci ; 49(2): E135-E142, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38569725

RESUMO

BACKGROUND: Recent reports have indicated that symptom exacerbation after a period of improvement, referred to as relapse, in early-stage psychosis could result in brain changes and poor disease outcomes. We hypothesized that substantial neuroimaging alterations may exist among patients who experience relapse in early-stage psychosis. METHODS: We studied patients with psychosis within 2 years after the first psychotic event and healthy controls. We divided patients into 2 groups, namely those who did not experience relapse between disease onset and the magnetic resonance imaging (MRI) scan (no-relapse group) and those who did experience relapse between these 2 timings (relapse group). We analyzed 3003 functional connectivity estimates between 78 regions of interest (ROIs) derived from resting-state functional MRI data by adjusting for demographic and clinical confounding factors. RESULTS: We studied 85 patients, incuding 54 in the relapse group and 31 in the no-relapse group, along with 94 healthy controls. We observed significant differences in 47 functional connectivity estimates between the relapse and control groups after multiple comparison corrections, whereas no differences were found between the no-relapse and control groups. Most of these pathological signatures (64%) involved the thalamus. The Jonckheere-Terpstra test indicated that all 47 functional connectivity changes had a significant cross-group progression from controls to patients in the no-relapse group to patients in the relapse group. LIMITATIONS: Longitudinal studies are needed to further validate the involvement and pathological importance of the thalamus in relapse. CONCLUSION: We observed pathological differences in neuronal connectivity associated with relapse in early-stage psychosis, which are more specifically associated with the thalamus. Our study implies the importance of considering neurobiological mechanisms associated with relapse in the trajectory of psychotic disorders.


Assuntos
Transtornos Psicóticos , Esquizofrenia , Humanos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Neuroimagem , Doença Crônica , Recidiva
5.
BMC Infect Dis ; 24(1): 1027, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39327564

RESUMO

BACKGROUND: Bacterial antimicrobial resistance (AMR) is a global threat to both humans and livestock. Despite this, there is limited global consensus on data-informed, priority areas for intervention in both sectors. We compare current livestock AMR data collection efforts with other variables pertinent to human and livestock AMR to identify critical data gaps and mutual priorities. METHODS: We globally synthesized livestock AMR data from open-source surveillance reports and point prevalence surveys stratified for six pathogens (Escherichia coli, Staphylococcus aureus, non-typhoidal Salmonella, Campylobacter spp., Enterococcus faecalis, Enterococcus faecium) and eleven antimicrobial classes important in human and veterinary use, published between 2000 and 2020. We also included all livestock species represented in the data: cattle, chickens, pigs, sheep, turkeys, ducks, horses, buffaloes, and goats. We compared this data with intended priorities calculated from: disability-adjusted life years (DALYs), livestock antimicrobial usage (AMU), livestock biomass, and a global correlation exercise between livestock and human proportion of resistant isolates. RESULTS: Resistance to fluoroquinolones and macrolides in Staphylococcus aureus were identified as priorities in many countries but, less than 10% of these reported livestock AMR data. Resistance data for Escherichia coli specific to cattle, chickens, and pigs, which we prioritized, were also well collected. AMR data collection on non-typhoidal Salmonella and other livestock species were often not prioritized. Of 232 categories prioritized by at least one country, data were only collected for 48% (n = 112). CONCLUSIONS: The lack of livestock AMR data globally for broad resistance in Staphylococcus aureus could underplay their zoonotic threat. Countries can bolster livestock AMR data collection, reporting, and intervention setting for Staphylococcus aureus as done for Escherichia coli. This framework can provide guidance on areas to strengthen AMR surveillance and decision-making for humans and livestock, and if done routinely, can adapt to resistance trends and priorities.


Assuntos
Antibacterianos , Farmacorresistência Bacteriana , Gado , Animais , Gado/microbiologia , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Bactérias/classificação , Bovinos , Monitoramento Epidemiológico
6.
Retina ; 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39312894

RESUMO

PURPOSE: to describe a new surgical technique that combines 4-point, flanged polypropylene scleral fixation with a hydrophobic IOL. METHODS: Using the Envista MX60 and 6.0 polypropylene, scleral 4-point fixation was achieved using a flanged-suture technique 5 times in a model eye and in a case series of 8 patients, retrospectively reviewed. The polypropylene is passed through each eyelet in a novel configuration (LOTO: Loop to Optic and Trailing ends to Outside). Conjunctival peritomies, scleral flaps/pockets, glue, and suture knots are avoided. The load needed for haptic fracture and scanning electron microscopy (SEM) at fracture sites were studied. RESULTS: Haptic fracture occurred once following the first model eye implantation due to excessive suture tension. The fracture load was similar between the LOTO and the simple-pass technique (1.08 ± 0.52 N vs 1.09 ± 0.32 N), suggesting no safety compromise. SEM did not disclose cheese-wiring effect. Over a mean follow-up of 10.8 months (range: 3 to 19; median 11.5 months), all cases experienced visual improvement with best-achieved-postoperative uncorrected visual acuity (BAPUCVA) of 20/25-20/200, and the IOL was well-centered. Postoperative IOL tilt averaged 2.9 degrees (range: 0 to 9.6; median: 2.9 degrees). Two patients developed post-operative CME treated topically. The first case developed flange extrusion that was readily repaired in clinic. CONCLUSIONS: This novel technique adds 2 main advantages to previously described flanged-suture techniques: 1) 4-point fixation of a hydrophobic IOL and 2) immediate application at the time of initial complicated cataract surgery since it requires no additional supply, IOL, or instrumentation.

7.
Int Ophthalmol ; 44(1): 275, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916818

RESUMO

PURPOSE: To assess the effectiveness of a switch to faricimab in individuals affected by DME and previously treated with aflibercept. METHODS: In this retrospective, single-center study, DME patients previously treated with at least 3 injections of aflibercept then switched to faricimab were enrolled. Best corrected visual acuity (BCVA) and central subfield thickness (CST) were recorded at baseline, at the time of the switch and at 6 months follow-up. At transition to faricimab, patients were categorized as "good visual responders" (≥ 5 letters from baseline) or "poor visual responders" (< 5 letters), and as "good anatomical responders" (any reduction in edema compared to baseline) or "poor anatomical responders" (no reduction or worsening of edema). Changes in BCVA and CST were recorded at 6 months after the switch to faricimab. RESULTS: 100 eyes of 100 patients (61 female, 61%) were switched to faricimab after a mean of 6.8 ± 3.3 aflibercept injections. At the 6 months follow-up, only "poor visual responders" (N = 62) demonstrated a meaningful increase in BCVA (Δswitch-6M = + 5 letters; P = 0.007), coupled with a reduction in CST (Δswitch-6M = - 67.9 µm; P = 0.004); participants with "poor anatomical response" upon transitioning exhibited a significant functional gain (Δswitch-6M = + 4.5 letters; p = 0.05) but limited CST enhancements (Δswitch-6M = - 95.1 µm; p = 0.05). CONCLUSIONS: Faricimab shows a positive impact on anatomical and functional metrics in DME cases refractory to aflibercept.


Assuntos
Inibidores da Angiogênese , Retinopatia Diabética , Injeções Intravítreas , Edema Macular , Receptores de Fatores de Crescimento do Endotélio Vascular , Proteínas Recombinantes de Fusão , Tomografia de Coerência Óptica , Acuidade Visual , Humanos , Receptores de Fatores de Crescimento do Endotélio Vascular/administração & dosagem , Receptores de Fatores de Crescimento do Endotélio Vascular/uso terapêutico , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/uso terapêutico , Feminino , Masculino , Estudos Retrospectivos , Edema Macular/tratamento farmacológico , Edema Macular/diagnóstico , Edema Macular/etiologia , Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/complicações , Retinopatia Diabética/fisiopatologia , Pessoa de Meia-Idade , Inibidores da Angiogênese/administração & dosagem , Tomografia de Coerência Óptica/métodos , Seguimentos , Idoso , Resultado do Tratamento , Substituição de Medicamentos/métodos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
8.
Angew Chem Int Ed Engl ; : e202414016, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39212480

RESUMO

Digital light processing (DLP) printing forms solid constructs from fluidic resins by photochemically crosslinking polymeric resins with reactive functional groups. DLP is used widely due to its efficient, high-resolution printing, but its use and translational potential has been limited in some applications as state-of-the-art resins experience unpredictable and anisotropic part shrinkage due to the use of solvent needed to reduce resin viscosity and layer dependent crosslinking. Herein, poly(allyl glycidyl ether succinate) (PAGES), a low viscosity, degradable polyester, was synthesized by ring opening copolymerization and used in combination with degradable thiol crosslinkers to afford a solvent free resin that can be utilized in DLP printing. Varying resin formulations of PAGES polymer are shown to decrease part shrinkage from 14% to 0.3%. Photochemically printed parts fabricated from PAGES possess tensile moduli between 0.43 and 6.18 MPa and degradation profiles are shown to vary between 12 and 40 days under accelerated conditions based on degree of polymerization and crosslink ratio.

9.
Hepatology ; 75(3): 550-566, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34510498

RESUMO

BACKGROUND AND AIMS: Hepatic ischemia-reperfusion injury (IRI) is the leading cause of early posttransplantation organ failure as mitochondrial respiration and ATP production are affected. A shortage of donors has extended liver donor criteria, including aged or steatotic livers, which are more susceptible to IRI. Given the lack of an effective treatment and the extensive transplantation waitlist, we aimed at characterizing the effects of an accelerated mitochondrial activity by silencing methylation-controlled J protein (MCJ) in three preclinical models of IRI and liver regeneration, focusing on metabolically compromised animal models. APPROACH AND RESULTS: Wild-type (WT), MCJ knockout (KO), and Mcj silenced WT mice were subjected to 70% partial hepatectomy (Phx), prolonged IRI, and 70% Phx with IRI. Old and young mice with metabolic syndrome were also subjected to these procedures. Expression of MCJ, an endogenous negative regulator of mitochondrial respiration, increases in preclinical models of Phx with or without vascular occlusion and in donor livers. Mice lacking MCJ initiate liver regeneration 12 h faster than WT and show reduced ischemic injury and increased survival. MCJ knockdown enables a mitochondrial adaptation that restores the bioenergetic supply for enhanced regeneration and prevents cell death after IRI. Mechanistically, increased ATP secretion facilitates the early activation of Kupffer cells and production of TNF, IL-6, and heparin-binding EGF, accelerating the priming phase and the progression through G1 /S transition during liver regeneration. Therapeutic silencing of MCJ in 15-month-old mice and in mice fed a high-fat/high-fructose diet for 12 weeks improves mitochondrial respiration, reduces steatosis, and overcomes regenerative limitations. CONCLUSIONS: Boosting mitochondrial activity by silencing MCJ could pave the way for a protective approach after major liver resection or IRI, especially in metabolically compromised, IRI-susceptible organs.


Assuntos
Fígado Gorduroso/metabolismo , Regeneração Hepática/fisiologia , Ativação de Macrófagos/fisiologia , Mitocôndrias/metabolismo , Proteínas Mitocondriais , Chaperonas Moleculares , Traumatismo por Reperfusão/metabolismo , Fatores Etários , Animais , Modelos Animais de Doenças , Metabolismo Energético/fisiologia , Inativação Gênica/fisiologia , Rejeição de Enxerto/prevenção & controle , Fígado/metabolismo , Transplante de Fígado/métodos , Camundongos , Camundongos Knockout , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Traumatismo por Reperfusão/prevenção & controle
10.
Ann Bot ; 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37410810

RESUMO

BACKGROUND AND AIMS: The Greater Cape Floristic Region is one of the world's biodiversity hotspots and is considered poor in polyploids. To test this assumption, ploidy variation was investigated in a widespread Cape shrub Dicerothamnus rhinocerotis (renosterbos, Asteraceae). The aim is to elucidate the cytotype distribution and population composition across the species range, and to assess differences in morphology, environmental niches, and genetics. METHODS: Ploidy level and genome size were determined via flow cytometry, cytotype assignment was confirmed by chromosome counting. RADseq analyses were used to infer genetic relationships. Cytotype climatic and environmental niches were compared using a range of environmental layers and a soil model, while morphological differences were examined using multivariate methods. KEY RESULTS: The survey of 171 populations and 2370 individuals showed that the species comprises diploid and tetraploid cytotypes, no intermediates and only 16.8 % of mixed populations. Mean 2C-values are 1.80-2.06 pg for diploids and 3.48-3.80 pg for tetraploids, with very similar monoploid genome sizes. Intra-cytotype variation showed a significant positive correlation with altitude and longitude in both cytotypes and with latitude in diploids. Although niches of both cytotypes are highly equivalent and similar, their optima and breadth are shifted due to differences mainly in isothermality and available water capacity. Morphometric analyses showed significant differences in the leaves and corolla traits, in the number of florets per capitulum, and cypsela dimensions between the two cytotypes. Genetic analyses revealed four groups, three of them including both cytotypes. CONCLUSIONS: Dicerothamnus rhinocerotis includes two distinct cytotypes that are genetically similar. While tetraploids arise several times independently within different genetic groups, morphological and ecological differences are evident between cytotypes. Our results open up new avenues for questions regarding the importance of ploidy in the megadiverse Cape flora, and exemplify the need for population-based studies focused on ploidy variation.

11.
Mol Psychiatry ; 26(8): 3931-3942, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33173197

RESUMO

Major mental illnesses such as schizophrenia (SZ) and bipolar disorder (BP) frequently accompany metabolic conditions, but their relationship is still unclear, in particular at the mechanistic level. We implemented an approach of "from population to neuron", combining population-based epidemiological analysis with neurobiological experiments using cell and animal models based on a hypothesis built from the epidemiological study. We characterized high-quality population data, olfactory neuronal cells biopsied from patients with SZ or BP, and healthy subjects, as well as mice genetically modified for insulin signaling. We accessed the Danish Registry and observed (1) a higher incidence of diabetes in people with SZ or BP and (2) higher incidence of major mental illnesses in people with diabetes in the same large cohort. These epidemiological data suggest the existence of common pathophysiological mediators in both diabetes and major mental illnesses. We hypothesized that molecules associated with insulin resistance might be such common mediators, and then validated the hypothesis by using two independent sets of olfactory neuronal cells biopsied from patients and healthy controls. In the first set, we confirmed an enrichment of insulin signaling-associated molecules among the genes that were significantly different between SZ patients and controls in unbiased expression profiling data. In the second set, olfactory neuronal cells from SZ and BP patients who were not pre-diabetic or diabetic showed reduced IRS2 tyrosine phosphorylation upon insulin stimulation, indicative of insulin resistance. These cells also displayed an upregulation of IRS1 protein phosphorylation at serine-312 at baseline (without insulin stimulation), further supporting the concept of insulin resistance in olfactory neuronal cells from SZ patients. Finally, Irs2 knockout mice showed an aberrant response to amphetamine, which is also observed in some patients with major mental illnesses. The bi-directional relationships between major mental illnesses and diabetes suggest that there may be common pathophysiological mediators associated with insulin resistance underlying these mental and physical conditions.


Assuntos
Transtorno Bipolar , Resistência à Insulina , Esquizofrenia , Animais , Transtorno Bipolar/genética , Humanos , Insulina , Camundongos , Neurônios , Esquizofrenia/genética
12.
Mol Psychiatry ; 26(7): 3502-3511, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33077854

RESUMO

Involvement of oxidative stress in the pathophysiology of schizophrenia (SZ) is suggested by studies of peripheral tissue. Nonetheless, it is unclear how such biological changes are linked to relevant, pathological neurochemistry, and brain function. We designed a multi-faceted study by combining biochemistry, neuroimaging, and neuropsychology to test how peripheral changes in a key marker for oxidative stress, glutathione (GSH), may associate with central neurochemicals or neuropsychological performance in health and in SZ. GSH in dorsal anterior cingulate cortex (dACC) was acquired as a secondary 3T 1H-MRS outcome using a MEGA-PRESS sequence. Fifty healthy controls and 46 patients with SZ were studied cross-sectionally, and analyses were adjusted for effects of confounding variables. We observed lower peripheral total GSH in SZ compared to controls in extracellular (plasma) and intracellular (lymphoblast) pools. Total GSH levels in plasma positively correlated with composite neuropsychological performance across the total population and within patients. Total plasma GSH levels were also positively correlated with the levels of Glx in the dACC across the total population, as well as within each individual group (controls, patients). Furthermore, the levels of dACC Glx and dACC GSH positively correlated with composite neuropsychological performance in the patient group. Exploring the relationship between systemic oxidative stress (in particular GSH), central glutamate, and cognition in SZ will benefit further from assessment of patients with more varied neuropsychological performance.


Assuntos
Esquizofrenia , Encéfalo/diagnóstico por imagem , Cognição , Ácido Glutâmico , Glutationa , Giro do Cíngulo , Humanos
13.
Curr Opin Anaesthesiol ; 35(3): 357-360, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35671024

RESUMO

PURPOSE OF REVIEW: The concept of quality improvement (QI) is well implemented in pediatric anesthesia. Conductance, reporting and publishing of QI projects and -results is well described and promoted. However, the perception of quality might differ between stakeholders and beneficiaries. Based on measures of quality as perceived by healthcare professionals and pediatric patients, a pragmatic approach to choosing the relevant quality measure is suggested. RECENT FINDINGS: Design of QI projects is often motivated by an incentive to avoid errors and adverse events, and with an overall aim to reduce morbidity and mortality. From a patient- and parent point of view, avoidance of perioperative stress and anxiety might be a priority measure of quality. SUMMARY: In an attempt to embrace both perspectives of quality in pediatric anesthesia care, it is suggested to choose quality items for improvement based on patient safety, professional excellency and benignancy. By following this approach, QI is expected to remain relevant to both healthcare professionals and patients.


Assuntos
Anestesia , Anestesiologia , Anestesia/efeitos adversos , Criança , Humanos , Segurança do Paciente , Melhoria de Qualidade
14.
J Biol Chem ; 295(1): 1-12, 2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31649031

RESUMO

African swine fever virus (ASFV) is a complex nucleocytoplasmic large DNA virus (NCLDV) that causes a devastating swine disease currently present in many countries of Africa, Europe, and Asia. Despite intense research efforts, relevant gaps in the architecture of the infectious virus particle remain. Here, we used single-particle cryo-EM to analyze the three-dimensional structure of the mature ASFV particle. Our results show that the ASFV virion, with a radial diameter of ∼2,080 Å, encloses a genome-containing nucleoid surrounded by two distinct icosahedral protein capsids and two lipoprotein membranes. The outer capsid forms a hexagonal lattice (triangulation number T = 277) composed of 8,280 copies of the double jelly-roll major capsid protein (MCP) p72, arranged in trimers displaying a pseudo-hexameric morphology, and of 60 copies of a penton protein at the vertices. The inner protein layer, organized as a T = 19 capsid, confines the core shell, and it is composed of the mature products derived from the ASFV polyproteins pp220 and pp62. Also, an icosahedral membrane lies between the two protein layers, whereas a pleomorphic envelope wraps the outer capsid. This high-level organization confers to ASFV a unique architecture among the NCLDVs that likely reflects the complexity of its infection process and may help explain current challenges in controlling it.


Assuntos
Vírus da Febre Suína Africana/ultraestrutura , Proteínas do Capsídeo/ultraestrutura , Capsídeo/ultraestrutura , Proteínas do Envelope Viral/ultraestrutura , Vírus da Febre Suína Africana/metabolismo , Animais , Proteínas do Capsídeo/química , Chlorocebus aethiops , Microscopia Crioeletrônica , Lipídeos/química , Multimerização Proteica , Células Vero , Proteínas do Envelope Viral/química
15.
Glycobiology ; 31(8): 1005-1017, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-33909073

RESUMO

Paucimannosidic glycans are restricted to the core structure [Man1-3GlcNAc2Fuc0-1] of N-glycans and are rarely found in mammalian tissues. Yet, especially [Man2-3GlcNAc2Fuc1] have been found significantly upregulated in tumors, including in colorectal and liver cancer. Mannitou IgM is a murine monoclonal antibody that was previously shown to recognize Man3GlcNAc2 with an almost exclusive selectivity. Here, we have sought the definition of the minimal glycan epitope of Mannitou IgM, initiated by screening on a newly designed paucimannosidic glycan microarray; among the best binders were Man3GlcNAc2 and its α1,6 core-fucosylated variant, Man3GlcNAc2Fuc1. Unexpectedly and in contrast to earlier findings, Man5GlcNAc2-type structures bind equally well and a large tolerance was observed for substitutions on the α1,6 arm. It was confirmed that any substitution on the single α1,3-linked mannose completely abolishes binding. Surface plasmon resonance for kinetic measurements of Mannitou IgM binding, either directly on the glycans or as presented on omega-1 and kappa-5 soluble egg antigens from the helminth parasite Schistosoma mansoni, showed submicromolar affinities. To characterize the epitope in greater and atomic detail, saturation transfer difference nuclear magnetic resonance spectroscopy was performed with the Mannitou antigen-binding fragment. The STD-NMR data demonstrated the strongest interactions with the aliphatic protons H1 and H2 of the α1-3-linked mannose and weaker imprints on its H3, H4 and H5 protons. In conclusion, Mannitou IgM binding requires a nonsubstituted α1,3-linked mannose branch of paucimannose also on proteins, making it a highly specific tool for the distinction of concurrent human tumor-associated carbohydrate antigens.


Assuntos
Glicoproteínas , Schistosoma mansoni , Animais , Proteínas de Ligação a DNA , Epitopos/química , Fucose/metabolismo , Glicoproteínas/metabolismo , Humanos , Imunoglobulina M , Mamíferos/metabolismo , Proteínas de Membrana , Camundongos , Polissacarídeos/química , Schistosoma mansoni/química , Schistosoma mansoni/metabolismo
16.
Mol Ecol ; 30(6): 1381-1397, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33503298

RESUMO

Phenotypic plasticity can serve as a stepping stone towards adaptation. Recently, studies have shown that gene expression contributes to emergent stress responses such as thermal tolerance, with tolerant and susceptible populations showing distinct transcriptional profiles. However, given the dynamic nature of gene expression, interpreting transcriptomic results in a way that elucidates the functional connection between gene expression and the observed stress response is challenging. Here, we present a conceptual framework to guide interpretation of gene expression reaction norms in the context of stress tolerance. We consider the evolutionary and adaptive potential of gene expression reaction norms and discuss the influence of sampling timing, transcriptomic resilience, as well as complexities related to life history when interpreting gene expression dynamics and how these patterns relate to host tolerance. We highlight corals as a case study to demonstrate the value of this framework for non-model systems. As species face rapidly changing environmental conditions, modulating gene expression can serve as a mechanistic link from genetic and cellular processes to the physiological responses that allow organisms to thrive under novel conditions. Interpreting how or whether a species can employ gene expression plasticity to ensure short-term survival will be critical for understanding the global impacts of climate change across diverse taxa.


Assuntos
Aclimatação , Antozoários , Adaptação Fisiológica , Animais , Evolução Biológica , Mudança Climática
17.
Int J Mol Sci ; 22(11)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34206141

RESUMO

The interaction of multi-LacNAc (Galß1-4GlcNAc)-containing N-(2-hydroxypropyl) methacrylamide (HPMA) copolymers with human galectin-1 (Gal-1) and the carbohydrate recognition domain (CRD) of human galectin-3 (Gal-3) was analyzed using NMR methods in addition to cryo-electron-microscopy and dynamic light scattering (DLS) experiments. The interaction with individual LacNAc-containing components of the polymer was studied for comparison purposes. For Gal-3 CRD, the NMR data suggest a canonical interaction of the individual small-molecule bi- and trivalent ligands with the lectin binding site and better affinity for the trivalent arrangement due to statistical effects. For the glycopolymers, the interaction was stronger, although no evidence for forming a large supramolecule was obtained. In contrast, for Gal-1, the results indicate the formation of large cross-linked supramolecules in the presence of multivalent LacNAc entities for both the individual building blocks and the polymers. Interestingly, the bivalent and trivalent presentation of LacNAc in the polymer did not produce such an increase, indicating that the multivalency provided by the polymer is sufficient for triggering an efficient binding between the glycopolymer and Gal-1. This hypothesis was further demonstrated by electron microscopy and DLS methods.


Assuntos
Proteínas Sanguíneas/química , Galectina 1/química , Galectinas/química , Metacrilatos/química , Polímeros/química , Acrilamidas/química , Acrilamidas/farmacologia , Sítios de Ligação/efeitos dos fármacos , Proteínas Sanguíneas/genética , Carboidratos/química , Microscopia Crioeletrônica , Galectina 1/genética , Galectinas/genética , Humanos , Ligantes , Metacrilatos/farmacologia , Polímeros/farmacologia , Ligação Proteica/efeitos dos fármacos
18.
J Perianesth Nurs ; 36(3): 275-278, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33637409

RESUMO

PURPOSE: Children undergoing surgery and general anesthesia often experience preoperative anxiety (POA) with related negative short-, medium- and long-term consequences. Anxiolytic premedication has negative side effects, and nonpharmacologic interventions are often resource demanding and not always readily available in a busy clinical setting. The use of an age-appropriate game on a tablet computer may reduce POA, postoperative pain, and occurrence of emergence delirium (ED). DESIGN: Children aged 3 to 6 years scheduled to undergo elective minor surgery were randomly assigned to play a game on a tablet computer while in the holding area before anesthesia (n = 30) or prepared as per departmental standard only (n = 30). METHODS: POA, ED, and levels of pain were assessed by the modified Yale Preoperative Anxiety Scale, Pediatric Anesthesia Emergence Delirium, and Face, Legs, Activity, Cry, Consolability scale, respectively. FINDINGS: A total of 60 children were randomized to either the intervention group or the control group. Gender, bodyweight, duration of anesthesia and surgery, and fentanyl dosages were comparable between the two groups. Tablet-gaming children tended to be less anxious than control subjects at the time of anesthesia induction (modified Yale Preoperative Anxiety Scale, 55.7 vs 65.8; 95% confidence interval, -0.63 to 20.8; P = .066). There was no difference in occurrence of ED or pain 20 minutes after arrival in the postanesthesia care unit. CONCLUSIONS: Although not statistically significant, the use of an age-appropriate tablet computer game may reduce the level of anxiety at the anesthetic induction in 3 to 6 years old children undergoing elective day-case surgery. However, the occurrence of ED and levels of pain appeared unaffected. Standardization of nonpharmacologic interventions to reduce perioperative anxiety and pain is required.


Assuntos
Ansiedade/prevenção & controle , Delírio do Despertar , Cuidados Pré-Operatórios , Período de Recuperação da Anestesia , Ansiedade/epidemiologia , Criança , Pré-Escolar , Computadores de Mão , Humanos
19.
Angew Chem Int Ed Engl ; 60(35): 19287-19296, 2021 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-34124805

RESUMO

The importance of multivalency for N-glycan-protein interactions has primarily been studied by attachment of minimal epitopes to artificial multivalent scaffold and not in the context of multi-antennary glycans. N-glycans can be modified by bisecting GlcNAc, core xylosides and fucosides, and extended N-acetyl lactosamine moieties. The impact of such modifications on glycan recognition are also not well understood. We describe here a chemoenzymatic methodology that can provide N-glycans expressed by the parasitic worm S. mansoni having unique epitopes at each antenna and containing core xyloside. NMR, computational and electron microscopy were employed to investigate recognition of the glycans by the human lectin DC-SIGN. It revealed that core xyloside does not influence terminal epitope recognition. The multi-antennary glycans bound with higher affinity to DC-SIGN compared to mono-valent counterparts, which was attributed to proximity-induced effective concentration. The multi-antennary glycans cross-linked DC-SIGN into a dense network, which likely is relevant for antigen uptake and intracellular routing.


Assuntos
Epitopos/química , Lectinas/análise , Polissacarídeos/química , Schistosoma mansoni/química , Animais , Humanos , Polissacarídeos/síntese química
20.
Ophthalmology ; 127(11): 1567-1577, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32507351

RESUMO

PURPOSE: To evaluate multimodal imaging findings of solitary idiopathic choroiditis (SIC; also known as unifocal helioid choroiditis) to clarify its origin, anatomic location, and natural course. DESIGN: Multicenter retrospective observational case series. PARTICIPANTS: Sixty-three patients with SIC in 1 eye. METHODS: Demographic and clinical data were collected. Multimodal imaging included color fundus photography, OCT (including swept-source OCT), OCT angiography (OCTA), fundus autofluorescence, fluorescein and indocyanine green angiography, and B-scan ultrasonography. MAIN OUTCOME MEASURES: Standardized grading of imaging features. RESULTS: Mean age at presentation was 56 ± 15 years (range, 12-83 years). Mean follow-up duration in 39 patients was 39 ± 55 months (range, 1 month-25 years). The lesions measured a mean of 2.4 × 2.1 mm in basal diameter, were located inferior (64%) or nasal to the optic disc, and appeared yellow (53%). No systemic associations were found. The lesions all appeared as an elevated subretinal mass, with OCT demonstrating all lesions to be confined to the sclera, not the choroid. On OCT, the deep lesion margin was visible in 12 eyes with a mean lesion thickness of 0.6 mm. Overlying choroidal thinning or absence was seen in 95% (mean choroidal thickness, 28 ± 35 µm). Mild subretinal fluid was observed overlying the lesions in 9 patients (14%). Retinal pigment epithelial disruption and overlying retinal thinning was observed in 56% and 57%, respectively. OCT angiography was performed in 13 eyes and demonstrated associated choroidal and lesional flow voids. Four lesions (6%) were identified at the macula, leading to visual loss in 1 patient. One lesion demonstrated growth and another lesion showed spontaneous resolution. CONCLUSIONS: In this largest series to date, multimodal imaging of SIC demonstrated a scleral location in all patients. The yellow and white clinical appearance may be related to scleral unmasking resulting from atrophy of overlying tissues. Additional associated features included documentation of deep margin on swept-source OCT, trace subretinal fluid in a few patients, and OCTA evidence of lesional flow voids. Because of the scleral location of this lesion in every patient, a new name, focal scleral nodule, is proposed.


Assuntos
Corioide/patologia , Corioidite/diagnóstico , Angiofluoresceinografia/métodos , Esclera/patologia , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Seguimentos , Fundo de Olho , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
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