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1.
Nat Immunol ; 23(4): 543-555, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35288714

RESUMO

Despite the success of the BNT162b2 mRNA vaccine, the immunological mechanisms that underlie its efficacy are poorly understood. Here we analyzed the innate and adaptive responses to BNT162b2 in mice, and show that immunization stimulated potent antibody and antigen-specific T cell responses, as well as strikingly enhanced innate responses after secondary immunization, which was concurrent with enhanced serum interferon (IFN)-γ levels 1 d following secondary immunization. Notably, we found that natural killer cells and CD8+ T cells in the draining lymph nodes are the major producers of this circulating IFN-γ. Analysis of knockout mice revealed that induction of antibody and T cell responses to BNT162b2 was not dependent on signaling via Toll-like receptors 2, 3, 4, 5 and 7 nor inflammasome activation, nor the necroptosis or pyroptosis cell death pathways. Rather, the CD8+ T cell response induced by BNT162b2 was dependent on type I interferon-dependent MDA5 signaling. These results provide insights into the molecular mechanisms by which the BNT162b2 vaccine stimulates immune responses.


Assuntos
Linfócitos T CD8-Positivos , Vacinas , Imunidade Adaptativa , Animais , Vacina BNT162 , Humanos , Imunidade Inata , Camundongos , Vacinas Sintéticas , Vacinas de mRNA
2.
Metab Eng ; 81: 227-237, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38072357

RESUMO

5-Aminovaleric acid (5-AVA), 5-hydroxyvalerate (5HV), copolymer P(3HB-co-5HV) of 3-hydroxybutyrate (3HB) and 5HV were produced from L-lysine as a substrate by recombinant Halomonas bluephagenesis constructed based on codon optimization, deletions of competitive pathway and L-lysine export protein, and three copies of davBA genes encoding L-lysine monooxygenase (DavB) and 5-aminovaleramide amidohydrolase (DavA) inserted into its genome to form H. bluephagenesis YF117ΔgabT1+2, which produced 16.4 g L-1 and 67.4 g L-1 5-AVA in flask cultures and in 7 L bioreactor, respectively. It was able to de novo synthesize 5-AVA from glucose by L-lysine-overproducing H. bluephagenesis TD226. Corn steep liquor was used instead of yeast extract for cost reduction during the 5-AVA production. Using promoter engineering based on Pporin mutant library for downstream genes, H. bluephagenesis YF117 harboring pSEVA341-Pporin42-yqhDEC produced 6 g L-1 5HV in shake flask growth, while H. bluephagenesis YF117 harboring pSEVA341-Pporin42-yqhDEC-Pporin278-phaCRE-abfT synthesized 42 wt% P(3HB-co-4.8 mol% 5HV) under the same condition. Thus, H. bluephagenesis was successfully engineered to produce 5-AVA and 5HV in supernatant and intracellular P(3HB-co-5HV) utilizing L-lysine as the substrate.


Assuntos
Halomonas , Engenharia Metabólica , Lisina/genética , Lisina/metabolismo , Halomonas/genética , Halomonas/metabolismo , Ácido 3-Hidroxibutírico/metabolismo , Poliésteres/metabolismo , Porinas/genética , Porinas/metabolismo
3.
Metab Eng ; 84: 95-108, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38901556

RESUMO

Microbial instability is a common problem during bio-production based on microbial hosts. Halomonas bluephagenesis has been developed as a chassis for next generation industrial biotechnology (NGIB) under open and unsterile conditions. However, the hidden genomic information and peculiar metabolism have significantly hampered its deep exploitation for cell-factory engineering. Based on the freshly completed genome sequence of H. bluephagenesis TD01, which reveals 1889 biological process-associated genes grouped into 84 GO-slim terms. An enzyme constrained genome-scale metabolic model Halo-ecGEM was constructed, which showed strong ability to simulate fed-batch fermentations. A visible salt-stress responsive landscape was achieved by combining GO-slim term enrichment and CVT-based omics profiling, demonstrating that cells deploy most of the protein resources by force to support the essential activity of translation and protein metabolism when exposed to salt stress. Under the guidance of Halo-ecGEM, eight transposases were deleted, leading to a significantly enhanced stability for its growth and bioproduction of various polyhydroxyalkanoates (PHA) including 3-hydroxybutyrate (3HB) homopolymer PHB, 3HB and 3-hydroxyvalerate (3HV) copolymer PHBV, as well as 3HB and 4-hydroxyvalerate (4HB) copolymer P34HB. This study sheds new light on the metabolic characteristics and stress-response landscape of H. bluephagenesis, achieving for the first time to construct a long-term growth stable chassis for industrial applications. For the first time, it was demonstrated that genome encoded transposons are the reason for microbial instability during growth in flasks and fermentors.


Assuntos
Halomonas , Halomonas/genética , Halomonas/metabolismo , Halomonas/enzimologia , Halomonas/crescimento & desenvolvimento , Engenharia Metabólica , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Redes e Vias Metabólicas/genética , Deleção de Genes , Modelos Biológicos
4.
Allergy ; 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39033312

RESUMO

BACKGROUND: During the COVID-19 pandemic, novel nanoparticle-based mRNA vaccines were developed. A small number of individuals developed allergic reactions to these vaccines although the mechanisms remain undefined. METHODS: To understand COVID-19 vaccine-mediated allergic reactions, we enrolled 19 participants who developed allergic events within 2 h of vaccination and 13 controls, nonreactors. Using standard hemolysis assays, we demonstrated that sera from allergic participants induced stronger complement activation compared to nonallergic subjects following ex vivo vaccine exposure. RESULTS: Vaccine-mediated complement activation correlated with anti-polyethelyne glycol (PEG) IgG (but not IgM) levels while anti-PEG IgE was undetectable in all subjects. Depletion of total IgG suppressed complement activation in select individuals. To investigate the effects of vaccine excipients on basophil function, we employed a validated indirect basophil activation test that stratified the allergic populations into high and low responders. Complement C3a and C5a receptor blockade in this system suppressed basophil response, providing strong evidence for complement involvement in vaccine-mediated basophil activation. Single-cell multiome analysis revealed differential expression of genes encoding the cytokine response and Toll-like receptor (TLR) pathways within the monocyte compartment. Differential chromatin accessibility for IL-13 and IL-1B genes was found in allergic and nonallergic participants, suggesting that in vivo, epigenetic modulation of mononuclear phagocyte immunophenotypes determines their subsequent functional responsiveness, contributing to the overall physiologic manifestation of vaccine reactions. CONCLUSION: These findings provide insights into the mechanisms underlying allergic reactions to COVID-19 mRNA vaccines, which may be used for future vaccine strategies in individuals with prior history of allergies or reactions and reduce vaccine hesitancy.

5.
Nature ; 555(7698): 683-687, 2018 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-29562237

RESUMO

The optimization of engineered metabolic pathways requires careful control over the levels and timing of metabolic enzyme expression. Optogenetic tools are ideal for achieving such precise control, as light can be applied and removed instantly without complex media changes. Here we show that light-controlled transcription can be used to enhance the biosynthesis of valuable products in engineered Saccharomyces cerevisiae. We introduce new optogenetic circuits to shift cells from a light-induced growth phase to a darkness-induced production phase, which allows us to control fermentation with only light. Furthermore, optogenetic control of engineered pathways enables a new mode of bioreactor operation using periodic light pulses to tune enzyme expression during the production phase of fermentation to increase yields. Using these advances, we control the mitochondrial isobutanol pathway to produce up to 8.49 ± 0.31 g l-1 of isobutanol and 2.38 ± 0.06 g l-1 of 2-methyl-1-butanol micro-aerobically from glucose. These results make a compelling case for the application of optogenetics to metabolic engineering for the production of valuable products.


Assuntos
Reatores Biológicos/microbiologia , Fermentação/efeitos da radiação , Luz , Engenharia Metabólica/métodos , Redes e Vias Metabólicas/efeitos da radiação , Optogenética/métodos , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/efeitos da radiação , Biocombustíveis/provisão & distribuição , Butanóis/metabolismo , Escuridão , Etanol/metabolismo , Pentanóis/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento
6.
Health Info Libr J ; 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38303128

RESUMO

BACKGROUND: Although knowledge sharing online has been recognised as an important strategy for health professionals to apply research findings to their practice, limited research exists on how to develop and implement these platforms to help facilitate collaboration and knowledge sharing. OBJECTIVES: This study evaluated an online knowledge sharing platform and community of practice developed in the North East of England and Yorkshire during COVID-19 to support UK health and care professionals to reduce the impact of the wider consequences of COVID-19. METHODS: Semi-structured interviews with stakeholders (n = 8) and users of C-WorKS (n = 13), followed by an online survey (n = 19) among a wider group of users to analyse knowledge use. RESULTS: Interview and survey findings highlighted several strengths, weaknesses, opportunities and threats to support future development of online knowledge sharing platforms. DISCUSSION: Online knowledge sharing supports six 'pillars' of successful research and innovation partnerships. This requires distributed forms of leadership and linking of different knowledge sharing strategies, and careful combination of platforms with communities of practice. CONCLUSION: Online knowledge sharing provides pragmatic and timely strategies for health professionals in the UK to apply research evidence to their practice. Our study provides generalisable, practical insights in how to develop and implement a knowledge sharing platform.

7.
Pediatr Dermatol ; 40(3): 422-427, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36579717

RESUMO

BACKGROUND/OBJECTIVES: The primary objective was to assess pain catastrophizing and functional disability in pediatric patients with epidermolysis bullosa (EB) and their parents/guardians. Secondary objectives included examining relationships between pain catastrophizing, functional disability, and correlations with other factors (e.g., age, disease severity, and percent of body surface area (BSA) involved). METHODS: Patients with EB ages 8-16 and their parents/guardians who were English or Spanish speaking completed a one-time online survey. Parent measures included: demographics questionnaire, Pain Catastrophizing Scale-Parent (PCS), and Parent Functional Disability Inventory (FDI). Child measures included: PCS child and child FDI. Higher scores on both scales indicate higher levels of catastrophizing and functional disability. RESULTS: Of 31 children, the mean age was 11.47 years and the majority (70.97%) had dystrophic EB. Mean scores were: 35.84 = PCS parent; 34.58 = PCS child; 30.87 = parent FDI; 29.77 = child FDI. Total scores for PCS parent, parent FDI, and child FDI increased significantly with disease severity and percentage of involved BSA (p < .01 for all). Total scores for PCS child increased significantly with percent of EB skin involvement (p = .04) but not disease severity. Older children reported more functional disability than their parents and younger children (p = .02). CONCLUSIONS: Our results demonstrate significant positive correlations between negative thoughts related to pain and the experience of functional difficulties in patients with EB and their caregivers. Psychological, psychiatric, and/or behavioral interventions to help managing chronic pain may be effective for patients with EB.


Assuntos
Dor Crônica , Epidermólise Bolhosa , Criança , Humanos , Adolescente , Pais/psicologia , Inquéritos e Questionários , Epidermólise Bolhosa/complicações , Catastrofização/psicologia
8.
Magn Reson Med ; 87(4): 1938-1951, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34904726

RESUMO

PURPOSE: Restriction spectrum imaging (RSI) decomposes the diffusion-weighted MRI signal into separate components of known apparent diffusion coefficients (ADCs). The number of diffusion components and optimal ADCs for RSI are organ-specific and determined empirically. The purpose of this work was to determine the RSI model for breast tissues. METHODS: The diffusion-weighted MRI signal was described using a linear combination of multiple exponential components. A set of ADC values was estimated to fit voxels in cancer and control ROIs. Later, the signal contributions of each diffusion component were estimated using these fixed ADC values. Relative-fitting residuals and Bayesian information criterion were assessed. Contrast-to-noise ratio between cancer and fibroglandular tissue in RSI-derived signal contribution maps was compared to DCE imaging. RESULTS: A total of 74 women with breast cancer were scanned at 3.0 Tesla MRI. The fitting residuals of conventional ADC and Bayesian information criterion suggest that a 3-component model improves the characterization of the diffusion signal over a biexponential model. Estimated ADCs of triexponential model were D1,3 = 0, D2,3 = 1.5 × 10-3 , and D3,3 = 10.8 × 10-3 mm2 /s. The RSI-derived signal contributions of the slower diffusion components were larger in tumors than in fibroglandular tissues. Further, the contrast-to-noise and specificity at 80% sensitivity of DCE and a subset of RSI-derived maps were equivalent. CONCLUSION: Breast diffusion-weighted MRI signal was best described using a triexponential model. Tumor conspicuity in breast RSI model is comparable to that of DCE without the use of exogenous contrast. These data may be used as differential features between healthy and malignant breast tissues.


Assuntos
Neoplasias da Mama , Imagem de Difusão por Ressonância Magnética , Teorema de Bayes , Mama/diagnóstico por imagem , Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Meios de Contraste , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Sensibilidade e Especificidade
9.
Pediatr Dermatol ; 39(1): 155-161, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34986507

RESUMO

Current medical literature and practice utilize limited resources to enhance pediatric patients' coping with and understanding of disease. Here, we provide a template for accessing current resources and developing practice-specific written materials focused on the child's experience.


Assuntos
Alopecia em Áreas , Dermatite Atópica , Dermatologia , Criança , Humanos
10.
J Magn Reson Imaging ; 53(5): 1581-1591, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33644939

RESUMO

BACKGROUND: Diffusion-weighted (DW) echo-planar imaging (EPI) is prone to geometric distortions due to B0 inhomogeneities. Both prospective and retrospective approaches have been developed to decrease and correct such distortions. PURPOSE: The purpose of this work was to evaluate the performance of reduced-field-of-view (FOV) acquisition and retrospective distortion correction methods in decreasing distortion artifacts for breast imaging. Coverage of the axilla in reduced-FOV DW magnetic resonance imaging (MRI) and residual distortion were also assessed. STUDY TYPE: Retrospective. POPULATION/PHANTOM: Breast phantom and 169 women (52.4 ± 13.4 years old) undergoing clinical breast MRI. FIELD STRENGTH/SEQUENCE: A 3.0 T/ full- and reduced-FOV DW gradient-echo EPI sequence. ASSESSMENT: Performance of reversed polarity gradient (RPG) and FSL topup in correcting breast full- and reduced-FOV EPI data was evaluated using the mutual information (MI) metric between EPI and anatomical images. Two independent breast radiologists determined if coverage on both EPI data sets was adequate to evaluate axillary nodes and identified residual nipple distortion artifacts. STATISTICAL TESTS: Two-way repeated-measures analyses of variance and post hoc tests were used to identify differences between EPI modality and distortion correction method. Generalized linear mixed effects models were used to evaluate differences in axillary coverage and residual nipple distortion. RESULTS: In a breast phantom, residual distortions were 0.16 ± 0.07 cm and 0.22 ± 0.13 cm in reduced- and full-FOV EPI with both methods, respectively. In patients, MI significantly increased after distortion correction of full-FOV (11 ± 5% and 18 ± 9%, RPG and topup) and reduced-FOV (8 ± 4% both) EPI data. Axillary nodes were observed in 99% and 69% of the cases in full- and reduced-FOV EPI images. Residual distortion was observed in 93% and 0% of the cases in full- and reduced-FOV images. DATA CONCLUSION: Minimal distortion was achieved with RPG applied to reduced-FOV EPI data. RPG improved distortions for full-FOV images but with more modest improvements and limited correction near the nipple. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 1.


Assuntos
Artefatos , Imagem Ecoplanar , Adulto , Idoso , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos
11.
J Gen Intern Med ; 34(10): 2005-2013, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30238404

RESUMO

BACKGROUND: Birth cohort screening is recommended for hepatitis C virus (HCV) and underserved populations are disproportionally affected by HCV. Little is known about the influence of race on the HCV care continuum in this population. OBJECTIVE: To assess the cascade of HCV care in a large racially diverse and underserved birth cohort. DESIGN: Retrospective cohort study using electronic medical record data abstracted until August 31, 2017. PATIENTS: 34,810 patients born between 1945 and 1965 engaged in primary care between October 1, 2014, and October 31, 2016, within the safety-net clinics of the San Francisco Health Network. MAIN MEASURES: Rate of hepatitis C testing, hepatitis C treatment, and response to therapy. RESULTS: Cohort characteristics were as follows: median age 59 years, 57.6% male, 25.5% White (20.6% Black, 17.7% Latino, 33.0% Asian/Pacific Islander (API), 2% other), and 32.6% preferred a non-English language. 99.7% had an HCV test (95.4% HCV antibody, 4.3% HCVRNA alone). Among HCV antibody-positive patients (N = 4587), 22.9% were not tested for confirmatory HCVRNA. Among viremic patients (N = 3673), 20.8% initiated HCV therapy, 90.6% achieved sustained virologic response (SVR) and 8.1% did not have a SVR test. HCV screening and treatment were highest in APIs (98.7 and 34.7% respectively; p < 0.001). Blacks had the highest chronic HCV rate (22.2%; p < 0.001). Latinos had the lowest SVR rate (81.3%; p = 0.01). On multivariable analysis, API race (vs White, OR 1.20; p = 0.001), presence of HIV co-infection (OR 1.58; p = 0.02), presence of chronic kidney disease (OR 0.47; p < 0.001), English (vs non-English) as preferred language (OR 0.54; p = 0.002), ALT (OR 0.39 per doubling; p < 0.001), and HCVRNA (OR 0.83 per 10-fold increase; p < 0.001) were associated with HCV treatment. CONCLUSIONS: Despite near-universal screening, gaps in active HCV confirmation, treatment, and verification of cure were identified and influenced by race. Tailored interventions to engage and treat diverse and underserved populations with HCV infection are needed.


Assuntos
Negro ou Afro-Americano/estatística & dados numéricos , Continuidade da Assistência ao Paciente/normas , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/tratamento farmacológico , Populações Vulneráveis/etnologia , Antivirais/uso terapêutico , Testes Diagnósticos de Rotina/estatística & dados numéricos , Uso de Medicamentos/estatística & dados numéricos , Registros Eletrônicos de Saúde , Feminino , Hepacivirus/isolamento & purificação , Hepatite C Crônica/etnologia , Hepatite C Crônica/virologia , Humanos , Masculino , Programas de Rastreamento/normas , Programas de Rastreamento/estatística & dados numéricos , Pessoa de Meia-Idade , Atenção Primária à Saúde/normas , Estudos Retrospectivos , São Francisco , Resposta Viral Sustentada , Resultado do Tratamento
12.
Age Ageing ; 45(6): 767-775, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27496936

RESUMO

OBJECTIVE: atrial fibrillation (AF) is associated with dementia. If AF-related cognitive decline is driven by cerebral embolic events, thromboprophylaxis may impact on this. This systematic review assessed the association between cognitive impairment and AF thromboprophylaxis. METHODS: two independent reviewers searched CINAHL, EMBASE, MEDLINE, PsycINFO, Web of Science Core Collection and Cochrane Library from inception until 12 November 2014. Eligible studies compared AF thromboprophylaxis to control with an outcome measure of cognition or dementia. Where data allowed, meta-analyses describing between-group differences in cognitive test scores or rates of incident dementia were performed. RESULTS: nineteen studies were eligible. For two prospective studies (one randomised controlled trial, RCT) comparing anticoagulation against antiplatelet therapy, change in Mini-Mental Score Examination (MMSE) score from baseline to last follow-up (maximal duration: 5.9 years) suggested a difference favouring anticoagulation (mean difference: 0.90, 95% CI: 0.29-1.51), in keeping with a trend seen in the single RCT (mean difference MMSE: 0.80, 95% CI: -0.07 to 1.67). Pooled odds ratio (OR) suggested no association with incident dementia, comparing anticoagulant to antiplatelet therapy (two studies, OR: 1.23, 95% CI: 0.80-1.91) or no treatment (three studies, OR: 0.89, 95% CI: 0.47-1.69). CONCLUSION: our analyses show no definitive evidence of cognitive benefit or harm from anticoagulation. We demonstrated a potential benefit of anticoagulation in comparison to antiplatelet over time. Larger scale studies with longer follow-up are needed to determine the true cognitive impact of AF thromboprophylaxis.


Assuntos
Anticoagulantes/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Transtornos Cognitivos/psicologia , Cognição , Fibrinolíticos/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Anticoagulantes/efeitos adversos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/epidemiologia , Fibrinolíticos/efeitos adversos , Humanos , Razão de Chances , Inibidores da Agregação Plaquetária/efeitos adversos , Fatores de Proteção , Medição de Risco , Fatores de Risco , Resultado do Tratamento
13.
Curr Opin Biotechnol ; 85: 103064, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38262074

RESUMO

The use of extremophile organisms such as Halomomas spp. can eliminate the need for fermentation sterilization, significantly reducing process costs. Microbial fermentation is considered a pivotal strategy to reduce reliance on fossil fuel resources; however, sustainable processes continue to incur higher costs than their chemical industry counterparts. Most organisms require equipment sterilization to prevent contamination, a practice that introduces complexity and financial strain. Fermentations involving extremophile organisms can eliminate the sterilization process, relying instead on conditions that are conductive solely to the growth of the desired organism. This review discusses current challenges in pilot- and industrial-scale bioproduction when using the extremophile bacteria Halomomas spp. under nonsterile conditions.


Assuntos
Halomonas , Fermentação , Bactérias
14.
Biotechnol Adv ; 71: 108320, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38272380

RESUMO

Polyhydroxyalkanoates (PHA) have evolved into versatile biopolymers, transcending their origins as mere bioplastics. This extensive review delves into the multifaceted landscape of PHA applications, shedding light on the diverse industries that have harnessed their potential. PHA has proven to be an invaluable eco-conscious option for packaging materials, finding use in films foams, paper coatings and even straws. In the textile industry, PHA offers a sustainable alternative, while its application as a carbon source for denitrification in wastewater treatment showcases its versatility in environmental remediation. In addition, PHA has made notable contributions to the medical and consumer sectors, with various roles ranging from 3D printing, tissue engineering implants, and cell growth matrices to drug delivery carriers, and cosmetic products. Through metabolic engineering efforts, PHA can be fine-tuned to align with the specific requirements of each industry, enabling the customization of material properties such as ductility, elasticity, thermal conductivity, and transparency. To unleash PHA's full potential, bridging the gap between research and commercial viability is paramount. Successful PHA production scale-up hinges on establishing direct supply chains to specific application domains, including packaging, food and beverage materials, medical devices, and agriculture. This review underscores that PHA's future rests on ongoing exploration across these industries and more, paving the way for PHA to supplant conventional plastics and foster a circular economy.


Assuntos
Poli-Hidroxialcanoatos , Poli-Hidroxialcanoatos/metabolismo , Biopolímeros , Alimentos
15.
mSystems ; 9(1): e0002623, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38078749

RESUMO

Microbial communities have evolved to colonize all ecosystems of the planet, from the deep sea to the human gut. Microbes survive by sensing, responding, and adapting to immediate environmental cues. This process is driven by signal transduction proteins such as histidine kinases, which use their sensing domains to bind or otherwise detect environmental cues and "transduce" signals to adjust internal processes. We hypothesized that an ecosystem's unique stimuli leave a sensor "fingerprint," able to identify and shed insight on ecosystem conditions. To test this, we collected 20,712 publicly available metagenomes from Host-associated, Environmental, and Engineered ecosystems across the globe. We extracted and clustered the collection's nearly 18M unique sensory domains into 113,712 similar groupings with MMseqs2. We built gradient-boosted decision tree machine learning models and found we could classify the ecosystem type (accuracy: 87%) and predict the levels of different physical parameters (R2 score: 83%) using the sensor cluster abundance as features. Feature importance enables identification of the most predictive sensors to differentiate between ecosystems which can lead to mechanistic interpretations if the sensor domains are well annotated. To demonstrate this, a machine learning model was trained to predict patient's disease state and used to identify domains related to oxygen sensing present in a healthy gut but missing in patients with abnormal conditions. Moreover, since 98.7% of identified sensor domains are uncharacterized, importance ranking can be used to prioritize sensors to determine what ecosystem function they may be sensing. Furthermore, these new predictive sensors can function as targets for novel sensor engineering with applications in biotechnology, ecosystem maintenance, and medicine.IMPORTANCEMicrobes infect, colonize, and proliferate due to their ability to sense and respond quickly to their surroundings. In this research, we extract the sensory proteins from a diverse range of environmental, engineered, and host-associated metagenomes. We trained machine learning classifiers using sensors as features such that it is possible to predict the ecosystem for a metagenome from its sensor profile. We use the optimized model's feature importance to identify the most impactful and predictive sensors in different environments. We next use the sensor profile from human gut metagenomes to classify their disease states and explore which sensors can explain differences between diseases. The sensors most predictive of environmental labels here, most of which correspond to uncharacterized proteins, are a useful starting point for the discovery of important environment signals and the development of possible diagnostic interventions.


Assuntos
Metagenômica , Microbiota , Humanos , Metagenoma , Aprendizado de Máquina , Planeta Terra
16.
Nanotechnology ; 24(36): 365604, 2013 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-23958555

RESUMO

A facile and straightforward method is suggested to synthesize nanoporous-TiO2 thin films for dye-sensitized solar cells (DSSCs). Silver/TiO2 co-sputtering led to the formation of nanocomposite films which consisted of silver nanoclusters with surrounding TiO2 matrices, and metal particles were subsequently etched by just immersing in nitric acid. Nanoporous-TiO2 DSSCs fabricated by this simple and effective process showed power-conversion efficiencies of up to 3.4% at a thickness of only 1.8 µm, which is much superior to that of conventional nanoparticulate-TiO2 DSSCs with similar thickness.

17.
Nanomaterials (Basel) ; 13(24)2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38133009

RESUMO

Over the last decade, research in organic-inorganic lead halide perovskite solar cells (PSCs) has gathered unprecedented momentum, putting the technology on the brink of full-scale commercialization. A wide range of strategies have been implemented for enhancing the power conversion efficiency of devices and modules, as well as improving stability toward high levels of irradiation, temperature, and humidity. Another key element in the path to commercialization is the scalability of device manufacturing, which requires large-scale deposition of conformal layers without compromising the delicate structure of the perovskite film. In this context, atomic layer deposition (ALD) tools excel in depositing high-quality conformal films with precise control of film composition and thickness over large areas at relatively low processing temperatures. In this commentary, we will briefly outline recent progress in PSC technology enabled by ALD tools, focusing on layers deposited above the absorber layer. These interlayers include charge transport layers, passivation layers, buffer layers, and encapsulation techniques. Additionally, we will discuss some of the challenges and potential avenues for research in PSC technology underpinned by ALD tools.

18.
Microb Biotechnol ; 16(2): 307-321, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36353812

RESUMO

Halomonas bluephagenesis TD1.0 was engineered to produce the biofuel propane, bioplastic poly-3-hydroxybutyrate (PHB), and biochemicals mandelate and hydroxymandelate in a single, semi-continuous batch fermentation under non-sterile conditions. Multi-product separation was achieved by segregation of the headspace gas (propane), fermentation broth ([hydroxy]mandelate) and cellular biomass (PHB). Engineering was performed by incorporating the genes encoding fatty acid photodecarboxylase (CvFAP) and hydroxymandelic acid synthase (SyHMAS) into a H. bluephagenesis hmgCAB cassette knockout to channel flux towards (hydroxy)mandelate. Design of Experiment strategies were coupled with fermentation trials to simultaneously optimize each product. Propane and mandelate titres were the highest reported for H. bluephagenesis (62 g/gDCW and 71 ± 10 mg/L respectively) with PHB titres (69% g/gDCW) comparable to other published studies. This proof-of-concept achievement of four easily separated products within one fermentation is a novel achievement probing the versatility of biotechnology, further elevating H. bluephagenesis as a Next Generation Industrial Biotechnology (NGIB) chassis by producing highly valued products at a reduced cost.


Assuntos
Halomonas , Fermentação , Halomonas/genética , Halomonas/metabolismo , Biocombustíveis , Propano , Hidroxibutiratos , Poliésteres/metabolismo , Biopolímeros
19.
Bioinform Biol Insights ; 17: 11779322231171779, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37200674

RESUMO

Multi-omic data mining has the potential to revolutionize synthetic biology especially in non-model organisms that have not been extensively studied. However, tangible engineering direction from computational analysis remains elusive due to the interpretability of large datasets and the difficulty in analysis for non-experts. New omics data are generated faster than our ability to use and analyse results effectively, resulting in strain development that proceeds through classic methods of trial-and-error without insight into complex cell dynamics. Here we introduce a user-friendly, interactive website hosting multi-omics data. Importantly, this new platform allows non-experts to explore questions in an industrially important chassis whose cellular dynamics are still largely unknown. The web platform contains a complete KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway enrichment analysis derived from principal components analysis, an interactive bio-cluster heatmap analysis of genes, and the Halomonas TD1.0 genome-scale metabolic (GEM) model. As a case study of the effectiveness of this platform, we applied unsupervised machine learning to determine key differences between Halomonas bluephagenesis TD1.0 cultivated under varied conditions. Specifically, cell motility and flagella apparatus are identified to drive energy expenditure usage at different osmolarities, and predictions were verified experimentally using microscopy and fluorescence labelled flagella staining. As more omics projects are completed, this landing page will facilitate exploration and targeted engineering efforts of the robust, industrial chassis H bluephagenesis for researchers without extensive bioinformatics background.

20.
JAAD Int ; 11: 165-173, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37252182

RESUMO

Chronic hand eczema (CHE) is persistent inflammatory dermatitis that may significantly affect the quality of life, with psychosocial effects, impact on school, work, and leisure activities, influence on socioeconomic status, and high health care costs. Pediatric-CHE (P-CHE) has a high prevalence yet has not been extensively studied in children and adolescents. There is minimal published data on P-CHE in North America, and no specific management guidelines. Limited prevalence data show broad ranges (0.9%-4.4%) in preschool and school children, with 1 study stating up to 10.0% 1-year prevalence for ages 16 to 19 years. Atopic dermatitis and allergic contact dermatitis appear important in the pathogenesis of this disease process, although there is limited pediatric data assessing disease associations and no standardized methodology for evaluating this disorder. Given the potential life-changing consequences of P-CHE, further research into this disease process is warranted to help generate best therapeutic practices and minimize this disease process' morbidity in adulthood.

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