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1.
Nat Methods ; 21(7): 1257-1274, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38890427

RESUMO

The dry mass and the orientation of biomolecules can be imaged without a label by measuring their permittivity tensor (PT), which describes how biomolecules affect the phase and polarization of light. Three-dimensional (3D) imaging of PT has been challenging. We present a label-free computational microscopy technique, PT imaging (PTI), for the 3D measurement of PT. PTI encodes the invisible PT into images using oblique illumination, polarization-sensitive detection and volumetric sampling. PT is decoded from the data with a vectorial imaging model and a multi-channel inverse algorithm, assuming uniaxial symmetry in each voxel. We demonstrate high-resolution imaging of PT of isotropic beads, anisotropic glass targets, mouse brain tissue, infected cells and histology slides. PTI outperforms previous label-free imaging techniques such as vector tomography, ptychography and light-field imaging in resolving the 3D orientation and symmetry of organelles, cells and tissue. We provide open-source software and modular hardware to enable the adoption of the method.


Assuntos
Algoritmos , Imageamento Tridimensional , Imageamento Tridimensional/métodos , Animais , Camundongos , Encéfalo/diagnóstico por imagem , Microscopia/métodos , Software , Humanos , Processamento de Imagem Assistida por Computador/métodos
2.
Microsurgery ; 41(2): 119-123, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33230926

RESUMO

BACKGROUND: Intraoral defects after tumor resection are often reconstructed with free tissue transfer. However, in patients who are not good candidates for free tissue transfer, regional flaps based on the superficial temporal artery can be utilized. The authors present our technique to reconstruct intraoral defects with the superficial temporal artery perforator (STAP) flap and early outcomes. METHODS: Five patients underwent STAP flaps for defects including the hard palate, buccal sulcus, floor of mouth, and retromolar trigone between 2017 and 2019. The mean defect size was 5.6 × 3.4 cm2 (3 × 3 cm2 - 7 × 4 cm2 ). The mean age was 74 (57-88) and all patients had recurrent cancer. External Doppler, indocyanine green laser angiography, and FLIR thermal imaging were used intra-operatively to identify the best perforators and plan for flap design. RESULTS: The mean flap size was 7.6 × 3.5 cm2 (6 × 3 cm2 - 10 × 5 cm2 ). Four flaps were based off of the posterior branch of the STA, while the fifth was based off of the anterior branch. Two donor sites were closed primarily, and three required skin grafts. One patient experienced partial flap necrosis. There were no complete flap losses and no donor site complications. Average follow up was 14.6 months (9-20 months). All patients maintained preoperative level of speech, mastication, and oral continence. CONCLUSIONS: The STAP flap can be based on the anterior or posterior branch of the superficial temporal artery and is a useful regional flap for intraoral defects after tumor resection.


Assuntos
Neoplasias , Retalho Perfurante , Procedimentos de Cirurgia Plástica , Idoso , Humanos , Transplante de Pele , Artérias Temporais/cirurgia
3.
Hosp Pharm ; 55(4): 268-272, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32742016

RESUMO

Purpose: The most recent published guidelines on Clostridium difficile-associated diarrhea (CDAD) developed by the Infectious Diseases Society of America (IDSA) were released in 2017 and outline its treatment based on severity of the disease and recurrence; however, a clear first-line agent has not been recommended specifically for severe CDAD. Methods: This retrospective chart review was approved by the institutional review board and consisted of three community hospitals and one academic medical center. To be included, patients need to meet criteria for severe CDAD and receive at least 72 hours of therapy. Patients received either oral vancomycin or fidaxomicin, in addition to other therapies for CDAD, and differences in outcomes such as cost obtained from a common charge center, rates of recurrence, time to recurrence as measured at time of positive to negative polymerase chain reaction (PCR) test, and mortality were assessed. Results: Of the 147 patients, 74 patients received fidaxomicin and 73 patients received oral vancomycin. The average hospitalization cost for patients receiving fidaxomicin was $129,338.69 and for patients receiving vancomycin was $153,563.81 (P = .26). Recurrence rates were lower with fidaxomicin compared with vancomycin (6.8% vs 17.6%; P = .047), and time to recurrence was longer with fidaxomicin versus vancomycin, but not statistically significant (96.8 ± 45.9 days vs 63.2 ± 66.9 days; P = .321). Mortality, length of stay in the intensive care unit, and overall length of stay were similar between the two therapies. Conclusions: In the treatment of severe CDAD, recurrence rates were lower and time to recurrence was higher with fidaxomicin compared with oral vancomycin. A clear financial benefit has yet to translate from these known findings.

4.
Phys Rev Lett ; 123(2): 027205, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31386536

RESUMO

We report on negative thermal expansion (NTE) in the high-field, half-magnetization plateau phase of the frustrated magnetic insulator CdCr_{2}O_{4}. Using dilatometry, we precisely map the phase diagram at fields of up to 30 T and identify a strong NTE associated with the collinear half-magnetization plateau for B>27 T. The resulting phase diagram is compared with a microscopic theory for spin-lattice coupling, and the origin of the NTE is identified as a large negative change in magnetization with temperature, coming from a nearly localized band of spin excitations in the plateau phase. These results provide useful guidelines for the discovery of new NTE materials.

5.
J Emerg Med ; 53(5): 662-679, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28939396

RESUMO

BACKGROUND: Angiotensin-converting enzyme inhibitor (ACEI)-induced angioedema can occur at any point during therapy and, when severe, can require mechanical ventilation. Standard agents for anaphylactic reactions have limited efficacy for bradykinin-mediated angioedema and, therefore, agents approved for hereditary angioedema are increasingly prescribed for these patients. OBJECTIVE OF THE REVIEW: This systematic review critically evaluates evidence describing the off-label use of fresh frozen plasma (FFP), prothrombin complex concentrate (PCC), complement 1 esterase inhibitor (C1-INH), icatibant, and ecallantide for treatment of ACEI-induced angioedema. DISCUSSION: A PubMed search was conducted and articles were cross-referenced for additional citations. All full-text clinical trials, case series, and case reports published in the English language describing pharmacologic treatment of ACEI-induced angioedema were included. Thirty-seven publications detailing FFP, PCC, and regimens approved for hereditary angioedema, including icatibant, ecallantide, and C1-INH, are reviewed extensively. CONCLUSIONS: While findings of decreased time to symptom resolution or a cessation in symptom progression have been reported with each of these therapies, additional data showing clinically relevant implications, such as reduced intensive care unit length of stay or avoidance of mechanical ventilation, are warranted, especially when taking cost into consideration. FFP has limited evidence demonstrating a benefit for treatment of ACEI-induced angioedema without consistent dosing strategies. However, given its wide availability and low potential for adverse reactions, FFP therapy may be reasonable. Of the novel agents traditionally used for hereditary angioedema, icatibant has the highest level of evidence and has been reported to be successful in limiting the progression of angioedema.


Assuntos
Angioedema/tratamento farmacológico , Angioedema/etiologia , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Uso Off-Label , Angioedema/induzido quimicamente , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Fatores de Coagulação Sanguínea/farmacologia , Fatores de Coagulação Sanguínea/uso terapêutico , Bradicinina/análogos & derivados , Bradicinina/farmacologia , Bradicinina/uso terapêutico , Proteínas Inativadoras do Complemento 1/farmacologia , Proteínas Inativadoras do Complemento 1/uso terapêutico , Humanos , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Plasma/metabolismo
6.
Nat Mater ; 13(8): 782-5, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24997736

RESUMO

The spin dynamics of all ferromagnetic materials are governed by two types of collective phenomenon: spin waves and domain walls. The fundamental processes underlying these collective modes, such as exchange interactions and magnetic anisotropy, all originate at the atomic scale. However, conventional probing techniques based on neutron and photon scattering provide high resolution in reciprocal space, and thereby poor spatial resolution. Here we present direct imaging of standing spin waves in individual chains of ferromagnetically coupled S = 2 Fe atoms, assembled one by one on a Cu(2)N surface using a scanning tunnelling microscope. We are able to map the spin dynamics of these designer nanomagnets with atomic resolution in two complementary ways. First, atom-to-atom variations of the amplitude of the quantized spin-wave excitations are probed using inelastic electron tunnelling spectroscopy. Second, we observe slow stochastic switching between two opposite magnetization states, whose rate varies strongly depending on the location of the tip along the chain. Our observations, combined with model calculations, reveal that switches of the chain are initiated by a spin-wave excited state that has its antinodes at the edges of the chain, followed by a domain wall shifting through the chain from one end to the other. This approach opens the way towards atomic-scale imaging of other types of spin excitation, such as spinon pairs and fractional end-states, in engineered spin chains.

7.
Vox Sang ; 108(2): 178-85, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25469720

RESUMO

BACKGROUND AND OBJECTIVES: Repeated blood donation produces iron deficiency. Changes in dietary iron intake do not prevent donation-induced iron deficiency. Prolonging the interdonation interval or using oral iron supplements can mitigate donation-induced iron deficiency. The most effective operational methods for reducing iron deficiency in donors are unknown. MATERIALS AND METHODS: 'Strategies To Reduce Iron Deficiency' (STRIDE) was a two-year, randomized, placebo-controlled study in blood donors. 692 donors were randomized into one of two educational groups or one of three interventional groups. Donors randomized to educational groups either received letters thanking them for donating, or, suggesting iron supplements or delayed donation if they had low ferritin. Donors randomized to interventional groups either received placebo, 19-mg or 38-mg iron pills. RESULTS: Iron deficient erythropoiesis was present in 52·7% of males and 74·6% of females at enrolment. Adverse events within 60 days of enrolment were primarily mild gastrointestinal symptoms (64%). The incidence of de-enrolment within 60 days was more common in the interventional groups than in the educational groups (P = 0·002), but not more common in those receiving iron than placebo (P = 0·68). CONCLUSION: The prevalence of iron deficient erythropoiesis in donors enrolled in the STRIDE study is comparable to previously described cohorts of regular blood donors. De-enrolment within 60 days was higher for donors receiving tablets, although no more common in donors receiving iron than placebo.


Assuntos
Anemia Ferropriva/prevenção & controle , Doadores de Sangue , Deficiências de Ferro , Ferro da Dieta/uso terapêutico , Adulto , Suplementos Nutricionais , Método Duplo-Cego , Eritropoese , Feminino , Humanos , Ferro/sangue , Ferro da Dieta/administração & dosagem , Ferro da Dieta/efeitos adversos , Masculino
8.
J Sci Med Sport ; 27(6): 368-372, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38849159

RESUMO

The present study aims to investigate the demographics and characteristics of scuba diving fatalities in the Philippines which can help in the identification of local trends and ultimately in the development of appropriate preventive measures. Data on scuba diving-related fatalities in the Philippines from 2008 to 2022 were manually retrieved from online news media sources. Information on age, sex, nationality, certification, purpose, and causative factors, whenever possible were collected and analysed. A total of 39 fatalities were identified having a median age of 43.5 (range 20-80). Majority of victims were males (n = 30), and of foreign ethnicity (n = 26). Asphyxia was identified as the possible disabling injury in almost half of the cases (n = 17). The causes of death based on autopsies were determined only for few cases which included drowning (n = 2), heart attack (n = 1), and traumatic injuries from a dynamite blast (n = 1). Potential vulnerable groups were identified to be the ageing population and foreign tourist divers. In the absence of an existing database, this preliminary report provides the best available evidence at this time concerning scuba diving fatalities in the Philippines.


Assuntos
Mergulho , Humanos , Filipinas/etnologia , Filipinas/epidemiologia , Mergulho/lesões , Mergulho/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Adulto , Feminino , Idoso , Adulto Jovem , Idoso de 80 Anos ou mais , Causas de Morte , Meios de Comunicação de Massa , Afogamento/mortalidade , Asfixia/mortalidade
9.
Open Forum Infect Dis ; 11(7): ofae342, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38983710

RESUMO

Infection management in solid organ transplantation poses unique challenges, with a diverse array of potential pathogens and associated antimicrobial therapies. With limited high-quality randomized clinical trials to direct optimal care, therapeutic "myths" may propagate and contribute to suboptimal or excessive antimicrobial use. We discuss 6 therapeutic myths with particular relevance to solid organ transplantation and provide recommendations for infectious diseases clinicians involved in the care of this high-risk population.

10.
Phys Rev Lett ; 111(12): 127203, 2013 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-24093296

RESUMO

Individual Fe atoms on a Cu(2)N/Cu(100) surface exhibit strong magnetic anisotropy due to the crystal field. We show that we can controllably enhance or reduce this anisotropy by adjusting the relative position of a second nearby Fe atom, with atomic precision, in a low-temperature scanning tunneling microscope. Local inelastic electron tunneling spectroscopy, combined with a qualitative first-principles model, reveal that the change in uniaxial anisotropy is driven by local strain due to the presence of the second Fe atom.

11.
Vox Sang ; 104(4): 317-23, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23294266

RESUMO

BACKGROUND AND OBJECTIVES: To determine the accuracy of fingerstick haemoglobin assessment in blood donors, the performance of a portable haemoglobinometer (HemoCue Hb 201+) was prospectively compared with that of an automated haematology analyzer (Cell-Dyn 4000). Haemoglobin values obtained by the latter were used as the 'true' result. MATERIAL AND METHODS: Capillary fingerstick samples were assayed by HemoCue in 150 donors. Fingerstick samples from two sites, one on each hand, were obtained from a subset of 50 subjects. Concurrent venous samples were tested using both HemoCue and Cell-Dyn devices. RESULTS: Capillary haemoglobin values (HemoCue) were significantly greater than venous haemoglobin values (HemoCue), which in turn were significantly greater than venous haemoglobin values by Cell-Dyn (mean ± SD: 14.05 ± 1.51, 13.89 ± 1.31, 13.62 ± 1.23, respectively; P < 0.01 for all comparisons among groups). Nine donors (6%) passed haemoglobin screening criteria (≥ 12.5 g/dl) by capillary HemoCue, but were deferred by Cell-Dyn values (false-pass). Five donors (3%) were deferred by capillary sampling, but passed by Cell-Dyn (false-fail). Substantial variability in repeated fingerstick HemoCue results was seen (mean haemoglobin 13.72 vs. 13.70 g/dl, absolute mean difference between paired samples 0.76 g/dl). Hand dominance was not a factor. CONCLUSIONS: Capillary samples assessed via a portable device yielded higher haemoglobin values than venous samples assessed on an automated analyzer. False-pass and false-fail rates were low and acceptable in the donor screening setting, with 'true' values not differing by a clinically significant degree from threshold values used to assess acceptability for blood donation.


Assuntos
Doadores de Sangue , Seleção do Doador/métodos , Hemoglobinometria/métodos , Hemoglobinas/análise , Adulto , Idoso , Capilares , Feminino , Hemoglobinometria/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Veias , Adulto Jovem
12.
Nat Genet ; 14(1): 90-4, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8782826

RESUMO

Non-insulin dependent diabetes mellitus (NIDDM) affects more than 100 million people worldwide and is associated with severe metabolic defects, including peripheral insulin resistance, elevated hepatic glucose production, and inappropriate insulin secretion. Family studies point to a major genetic component, but specific susceptibility genes have not yet been identified-except for rare early-onset forms with monogenic or mitochondrial inheritance. We have screened over 4,000 individuals from a population isolate in western Finland, identified 26 families (comprising 217 individuals) enriched for NIDDM and performed a genome-wide scan using non-parametric linkage analysis. We found no significant evidence for linkage when the families were analysed together, but strong evidence for linkage when families were classified according to mean insulin levels in affecteds (in oral glucose tolerance tests). Specifically, families with the lowest insulin levels showed linkage (P = 2 x 10(-6)) to chromosome 12 near D12S1349. Interestingly, this region contains the gene causing the rare, dominant, early-onset form of diabetes MODY3. Unlike MODY3 families, the Finnish families with low insulin have an age-of-onset typical for NIDDM (mean = 58 years). We infer the existence of a gene NIDDM2 causing NIDDM associated with low insulin secretion, and suggest that NIDDM2 and MODY3 may represent different alleles of the same gene.


Assuntos
Mapeamento Cromossômico , Cromossomos Humanos Par 12 , Diabetes Mellitus Tipo 2/genética , Insulina/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Finlândia , Testes Genéticos , Humanos , Insulina/genética , Secreção de Insulina , Masculino , Pessoa de Meia-Idade , Linhagem
13.
Pathogens ; 12(5)2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37242341

RESUMO

A multiplexed enzyme-linked immunosorbent assay (ELISA) that simultaneously measures antibody binding to multiple antigens can extend the impact of serosurveillance studies, particularly if the assay approaches the simplicity, robustness, and accuracy of a conventional single-antigen ELISA. Here, we report on the development of multiSero, an open-source multiplex ELISA platform for measuring antibody responses to viral infection. Our assay consists of three parts: (1) an ELISA against an array of proteins in a 96-well format; (2) automated imaging of each well of the ELISA array using an open-source plate reader; and (3) automated measurement of optical densities for each protein within the array using an open-source analysis pipeline. We validated the platform by comparing antibody binding to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) antigens in 217 human sera samples, showing high sensitivity (0.978), specificity (0.977), positive predictive value (0.978), and negative predictive value (0.977) for classifying seropositivity, a high correlation of multiSero determined antibody titers with commercially available SARS-CoV-2 antibody tests, and antigen-specific changes in antibody titer dynamics upon vaccination. The open-source format and accessibility of our multiSero platform can contribute to the adoption of multiplexed ELISA arrays for serosurveillance studies, for SARS-CoV-2 and other pathogens of significance.

14.
Nat Methods ; 6(5): 339-42, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19404253

RESUMO

Structured-illumination microscopy can double the resolution of the widefield fluorescence microscope but has previously been too slow for dynamic live imaging. Here we demonstrate a high-speed structured-illumination microscope that is capable of 100-nm resolution at frame rates up to 11 Hz for several hundred time points. We demonstrate the microscope by video imaging of tubulin and kinesin dynamics in living Drosophila melanogaster S2 cells in the total internal reflection mode.


Assuntos
Citofotometria/métodos , Iluminação , Microscopia de Vídeo/métodos , Algoritmos , Animais , Linhagem Celular , Citofotometria/instrumentação , Drosophila melanogaster , Processamento Eletrônico de Dados , Análise de Fourier , Processamento de Imagem Assistida por Computador , Cinesinas/metabolismo , Microscopia de Fluorescência/métodos , Microscopia de Vídeo/instrumentação , Microtúbulos/metabolismo , Fuso Acromático/metabolismo , Tubulina (Proteína)/metabolismo
15.
Mar Pollut Bull ; 185(Pt A): 114241, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36274562

RESUMO

As an archipelago, the Philippines is heavily engaged in domestic and foreign shipping activities which makes it highly vulnerable to oil pollution. It is the purpose of this present paper to make a follow-up review of the oil spill situation in the Philippines which provides analysis and evaluation of aquatic oil spills in the past 22 years. Results showed that the frequency and volume of oil spills generally occur in areas with high maritime traffic and experienced short-term decreases on periods affected by economic recessions. The sources and causes of oil spills are discussed while examining the possible influences of the changing climate. While, these had been identified, there is a gap in the incident reporting of oil spills. It is recommended that data records on oil spill incidents in the Philippines be systematic, consistent and comprehensively entail information not limited to date, locality, source, cause, and spillage amount.


Assuntos
Poluição por Petróleo , Poluição por Petróleo/análise , Filipinas , Navios , Clima
16.
Pharmacotherapy ; 42(12): 905-920, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36373198

RESUMO

The introduction of safe and highly effective direct acting antivirals (DAAs) has significantly improved hepatitis C virus (HCV) treatment outcomes after transplant. The solid organ transplant community has sought to identify strategies aimed at increasing the donor pool including the utilization of HCV-viremic organs in HCV-negative recipients. We will review the existing literature to evaluate DAA use for the treatment of HCV viremia post-liver transplant in patients who receive HCV-viremic allografts. A PubMed search was conducted and references for each study were also reviewed to identify additional articles. Randomized controlled trials, cohort studies, case series, and case reports were included if: published in English language, evaluated DAA treatment outcomes after liver only or simultaneous liver-kidney transplantation with HCV-viremic allografts in HCV-negative recipients, and had full-text article availability. Our review included 16 studies and 2 case reports. The majority of liver transplant recipients were treated with a pangenotypic DAA for 12 weeks with a heterogeneous median time to initiation (range 1.7-118 days). Sustained virologic response was assessed in 253 liver transplant patients with 99.6% achieving cure with minimal DAA-attributed adverse drug events. There were 23 reported episodes of rejection, 12 deaths, and 1 graft loss among all studies. Treatment with DAA after transplantation of HCV-viremic livers into HCV-negative recipients appears to be safe and effective; however, long-term outcomes remain unknown. Transplant pharmacists play a key role in the development of center-specific protocols to optimize post-transplant outcomes in this unique patient population.


Assuntos
Hepatite C Crônica , Transplante de Fígado , Humanos , Hepacivirus , Antivirais/uso terapêutico
17.
Mol Biol Cell ; 33(6): ar59, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35138913

RESUMO

A cell's shape and motion represent fundamental aspects of cell identity and can be highly predictive of function and pathology. However, automated analysis of the morphodynamic states remains challenging for most cell types, especially primary human cells where genetic labeling may not be feasible. To enable automated and quantitative analysis of morphodynamic states, we developed DynaMorph-a computational framework that combines quantitative live cell imaging with self-supervised learning. To demonstrate the robustness and utility of this approach, we used DynaMorph to annotate morphodynamic states observed with label-free measurements of optical density and anisotropy of live microglia isolated from human brain tissue. These cells show complex behavior and have varied responses to disease-relevant perturbations. DynaMorph generates quantitative morphodynamic representations that can be used to compare the effects of the perturbations. Using DynaMorph, we identify distinct morphodynamic states of microglia polarization and detect rare transition events between states. The concepts and the methods presented here can facilitate automated discovery of functional states of diverse cellular systems.


Assuntos
Encéfalo , Aprendizado de Máquina Supervisionado , Anisotropia , Humanos
18.
Science ; 375(6585): eabi6983, 2022 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-35271311

RESUMO

Elucidating the wiring diagram of the human cell is a central goal of the postgenomic era. We combined genome engineering, confocal live-cell imaging, mass spectrometry, and data science to systematically map the localization and interactions of human proteins. Our approach provides a data-driven description of the molecular and spatial networks that organize the proteome. Unsupervised clustering of these networks delineates functional communities that facilitate biological discovery. We found that remarkably precise functional information can be derived from protein localization patterns, which often contain enough information to identify molecular interactions, and that RNA binding proteins form a specific subgroup defined by unique interaction and localization properties. Paired with a fully interactive website (opencell.czbiohub.org), our work constitutes a resource for the quantitative cartography of human cellular organization.


Assuntos
Mapeamento de Interação de Proteínas , Proteínas/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Sistemas CRISPR-Cas , Análise por Conglomerados , Conjuntos de Dados como Assunto , Corantes Fluorescentes , Células HEK293 , Humanos , Imunoprecipitação , Aprendizado de Máquina , Espectrometria de Massas , Microscopia Confocal , Proteínas de Ligação a RNA/metabolismo , Análise Espacial
19.
Cell Stem Cell ; 28(12): 2153-2166.e6, 2021 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-34536354

RESUMO

Microglia are resident macrophages in the brain that emerge in early development and respond to the local environment by altering their molecular and phenotypic states. Fundamental questions about microglia diversity and function during development remain unanswered because we lack experimental strategies to interrogate their interactions with other cell types and responses to perturbations ex vivo. We compared human microglia states across culture models, including cultured primary and pluripotent stem cell-derived microglia. We developed a "report card" of gene expression signatures across these distinct models to facilitate characterization of their responses across experimental models, perturbations, and disease conditions. Xenotransplantation of human microglia into cerebral organoids allowed us to characterize key transcriptional programs of developing microglia in vitro and reveal that microglia induce transcriptional changes in neural stem cells and decrease interferon signaling response genes. Microglia additionally accelerate the emergence of synchronized oscillatory network activity in brain organoids by modulating synaptic density.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Neurais , Encéfalo , Diferenciação Celular , Humanos , Microglia , Modelos Teóricos , Organoides
20.
medRxiv ; 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34013298

RESUMO

Serology has provided valuable diagnostic and epidemiological data on antibody responses to SARS-CoV-2 in diverse patient cohorts. Deployment of high content, multiplex serology platforms across the world, including in low and medium income countries, can accelerate longitudinal epidemiological surveys. Here we report multiSero, an open platform to enable multiplex serology with up to 48 antigens in a 96-well format. The platform consists of three components: ELISA-array of printed proteins, a commercial or home-built plate reader, and modular python software for automated analysis (pysero). We validate the platform by comparing antibody titers against the SARS-CoV-2 Spike, receptor binding domain (RBD), and nucleocapsid (N) in 114 sera from COVID-19 positive individuals and 87 pre-pandemic COVID-19 negative sera. We report data with both a commercial plate reader and an inexpensive, open plate reader (nautilus). Receiver operating characteristic (ROC) analysis of classification with single antigens shows that Spike and RBD classify positive and negative sera with the highest sensitivity at a given specificity. The platform distinguished positive sera from negative sera when the reactivity of the sera was equivalent to the binding of 1 ng mL âˆ'1 RBD-specific monoclonal antibody. We developed normalization and classification methods to pool antibody responses from multiple antigens and multiple experiments. Our results demonstrate a performant and accessible pipeline for multiplexed ELISA ready for multiple applications, including serosurveillance, identification of viral proteins that elicit antibody responses, differential diagnosis of circulating pathogens, and immune responses to vaccines.

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