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1.
J Phys Chem B ; 128(4): 1108-1117, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38232317

RESUMO

We have developed a multi-input E(n) equivariant graph convolution-based model designed for the prediction of chemical properties that result from the interaction of heterogeneous molecular structures. By incorporating spatial features and constraining the functions learned from these features to be equivariant to E(n) symmetries, the interactional-equivariant graph neural network (IEGNN) can efficiently learn from the 3D structure of multiple molecules. To verify the IEGNN's capability to learn interactional properties, we tested the model's performance on three molecular data sets, two of which are curated in this study and made publicly available for future interactional model benchmarking. To enable the loading of these data sets, an open-source data structure based on the PyTorch Geometric library for batch loading multigraph data points is also created. Finally, the IEGNN's performance on a data set consisting of an unknown interactional relationship (the frictional properties resulting between monolayers with variable composition) is examined. The IEGNN model developed was found to have the lowest mean absolute percent error for the predicted tribological properties of four of the six data sets when compared to previous methods.

2.
J Chem Inf Model ; 63(4): 1218-1228, 2023 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-36791286

RESUMO

MoSDeF-GOMC is a python interface for the Monte Carlo software GOMC to the Molecular Simulation Design Framework (MoSDeF) ecosystem. MoSDeF-GOMC automates the process of generating initial coordinates, assigning force field parameters, and writing coordinate (PDB), connectivity (PSF), force field parameter, and simulation control files. The software lowers entry barriers for novice users while allowing advanced users to create complex workflows that encapsulate simulation setup, execution, and data analysis in a single script. All relevant simulation parameters are encoded within the workflow, ensuring reproducible simulations. MoSDeF-GOMC's capabilities are illustrated through a number of examples, including prediction of the adsorption isotherm for CO2 in IRMOF-1, free energies of hydration for neon and radon over a broad temperature range, and the vapor-liquid coexistence curve of a four-component surrogate for the jet fuel S-8. The MoSDeF-GOMC software is available on GitHub at https://github.com/GOMC-WSU/MoSDeF-GOMC.


Assuntos
Ecossistema , Software , Fluxo de Trabalho , Método de Monte Carlo , Simulação por Computador
3.
Int J Biol Macromol ; 230: 123175, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36623624

RESUMO

The global trend of increasing energy demand along the large volume of wastewater generated annually from the paper pulping and cellulose production industries are considered as serious dilemma that may need to be solved within these current decades. Within this discipline, lignin, silica or lignin-silica hybrids attained from biomass material have been considered as prospective candidates for the synthesis of advanced materials. In this study, the roles and linking mechanism between lignin and silica in plants were studied and evaluated. The effects of the extraction method on the quality of the obtained material were summarized to show that depending on the biomass feedstocks, different retrieval processes should be considered. The combination of alkaline treatment and acidic pH adjustment is proposed as an effective method to recover lignin-silica with high applicability for various types of raw materials. From considerations of the advanced applications of lignin and silica materials in environmental remediation, electronic devices and rubber fillers future valorizations hold potential in conductive materials and electrochemistry. Along with further studies, this research could not only contribute to the development of zero-waste manufacturing processes but also propose a solution for the fully exploiting of by-products from agricultural production.


Assuntos
Lignina , Dióxido de Silício , Celulose , Plantas , Biomassa
4.
J Chem Phys ; 156(15): 154902, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35459321

RESUMO

Monolayer films have shown promise as a lubricating layer to reduce friction and wear of mechanical devices with separations on the nanoscale. These films have a vast design space with many tunable properties that can affect their tribological effectiveness. For example, terminal group chemistry, film composition, and backbone chemistry can all lead to films with significantly different tribological properties. This design space, however, is very difficult to explore without a combinatorial approach and an automatable, reproducible, and extensible workflow to screen for promising candidate films. Using the Molecular Simulation Design Framework (MoSDeF), a combinatorial screening study was performed to explore 9747 unique monolayer films (116 964 total simulations) and a machine learning (ML) model using a random forest regressor, an ensemble learning technique, to explore the role of terminal group chemistry and its effect on tribological effectiveness. The most promising films were found to contain small terminal groups such as cyano and ethylene. The ML model was subsequently applied to screen terminal group candidates identified from the ChEMBL small molecule library. Approximately 193 131 unique film candidates were screened with approximately a five order of magnitude speed-up in analysis compared to simulation alone. The ML model was thus able to be used as a predictive tool to greatly speed up the initial screening of promising candidate films for future simulation studies, suggesting that computational screening in combination with ML can greatly increase the throughput in combinatorial approaches to generate in silico data and then train ML models in a controlled, self-consistent fashion.


Assuntos
Ensaios de Triagem em Larga Escala , Simulação de Dinâmica Molecular , Fricção , Aprendizado de Máquina
5.
J Am Acad Dermatol ; 87(3): 559-566, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35487332

RESUMO

BACKGROUND: The incidence of systemic lupus in children with discoid lupus is unknown. OBJECTIVE: This study assessed the baseline characteristics of patients with pediatric discoid lupus erythematosus (pDLE). METHODS: Medical records at 17 sites were reviewed for pediatric dermatology and rheumatology patients with discoid lupus erythematosus. The inclusion criteria were clinical and/or histopathologic diagnosis of discoid lupus erythematosus with an age at onset of <18 years. Baseline data were collected at the first documented visit. Outcomes included diagnosis of systemic lupus erythematosus (SLE) at the baseline visit using the 1997 American College of Rheumatology (primary) and the 2012 Systemic Lupus International Collaborating Clinics (secondary) criteria. RESULTS: Of the >1500 charts reviewed, 438 patients met the inclusion criteria. The cohort was predominantly female (72%) and racially/ethnically diverse. A diagnosis of SLE at the baseline visit (pDLE + SLE) was rendered in 162 (37%) patients using the American College of Rheumatology and in 181 (41%) patients using the Systemic Lupus International Collaborating Clinics criteria. Patients with pDLE + SLE were older at the time of rash onset (median, 12.9 vs 8.9 years; P < .001), with shorter time from discoid lupus erythematosus onset to diagnosis, compared with patients with pDLE-only (median, 2 vs 7 months; P < .001). Patients with pDLE + SLE were more likely to be female (P = .004), with generalized discoid lupus erythematosus and clinically aggressive disease, including end-organ involvement, positive serologies, and higher- titer levels of antinuclear antibodies (P < .001). LIMITATIONS: Retrospective study. CONCLUSION: A diagnosis of discoid lupus erythematosus in adolescence should prompt thorough screening for SLE.


Assuntos
Lúpus Eritematoso Discoide , Lúpus Eritematoso Sistêmico , Adolescente , Criança , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Lúpus Eritematoso Discoide/diagnóstico , Lúpus Eritematoso Discoide/epidemiologia , Lúpus Eritematoso Sistêmico/epidemiologia , Masculino , Estudos Retrospectivos
6.
Mol Phys ; 118(9-10)2020.
Artigo em Inglês | MEDLINE | ID: mdl-33100401

RESUMO

Systems composed of soft matter (e.g., liquids, polymers, foams, gels, colloids, and most biological materials) are ubiquitous in science and engineering, but molecular simulations of such systems pose particular computational challenges, requiring time and/or ensemble-averaged data to be collected over long simulation trajectories for property evaluation. Performing a molecular simulation of a soft matter system involves multiple steps, which have traditionally been performed by researchers in a "bespoke" fashion, resulting in many published soft matter simulations not being reproducible based on the information provided in the publications. To address the issue of reproducibility and to provide tools for computational screening, we have been developing the open-source Molecular Simulation and Design Framework (MoSDeF) software suite. In this paper, we propose a set of principles to create Transparent, Reproducible, Usable by others, and Extensible (TRUE) molecular simulations. MoSDeF facilitates the publication and dissemination of TRUE simulations by automating many of the critical steps in molecular simulation, thus enhancing their reproducibility. We provide several examples of TRUE molecular simulations: All of the steps involved in creating, running and extracting properties from the simulations are distributed on open-source platforms (within MoSDeF and on GitHub), thus meeting the definition of TRUE simulations.

7.
Hum Reprod ; 34(1): 69-78, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30428062

RESUMO

STUDY QUESTION: Does incisional endometriosis (IE) harbor somatic cancer-driver mutations? SUMMARY ANSWER: We found that approximately one-quarter of IE cases harbor somatic-cancer mutations, which commonly affect components of the MAPK/RAS or PI3K-Akt-mTor signaling pathways. WHAT IS KNOWN ALREADY: Despite the classification of endometriosis as a benign gynecological disease, it shares key features with cancers such as resistance to apoptosis and stimulation of angiogenesis and is well-established as the precursor of clear cell and endometrioid ovarian carcinomas. Our group has recently shown that deep infiltrating endometriosis (DE), a form of endometriosis that rarely undergoes malignant transformation, harbors recurrent somatic mutations. STUDY DESIGN, SIZE, DURATION: In a retrospective study comparing iatrogenically induced and endogenously occurring forms of endometriosis unlikely to progress to cancer, we examined endometriosis specimens from 40 women with IE and 36 women with DE. Specimens were collected between 2004 and 2017 from five hospital sites in either Canada, Germany or the Netherlands. IE and DE cohorts were age-matched and all women presented with histologically typical endometriosis without known history of malignancy. PARTICIPANTS/MATERIALS, SETTING, METHODS: Archival tissue specimens containing endometriotic lesions were macrodissected and/or laser-capture microdissected to enrich endometriotic stroma and epithelium and a hypersensitive cancer hotspot sequencing panel was used to assess for presence of somatic mutations. Mutations were subsequently validated using droplet digital PCR. PTEN and ARID1A immunohistochemistry (IHC) were performed as surrogates for somatic events resulting in functional loss of respective proteins. MAIN RESULTS AND THE ROLE OF CHANCE: Overall, we detected somatic cancer-driver events in 11 of 40 (27.5%) IE cases and 13 of 36 (36.1%) DE cases, including hotspot mutations in KRAS, ERBB2, PIK3CA and CTNNB1. Heterogeneous PTEN loss occurred at similar rates in IE and DE (7/40 vs 5/36, respectively), whereas ARID1A loss only occurred in a single case of DE. While rates of detectable somatic cancer-driver events between IE and DE are not statistically significant (P > 0.05), KRAS activating mutations were more prevalent in DE. LIMITATIONS, REASONS FOR CAUTION: Detection of somatic cancer-driver events were limited to hotspots analyzed in our panel-based sequencing assay and loss of protein expression by IHC from archival tissue. Whole genome or exome sequencing, or epigenetic analysis may uncover additional somatic alterations. Moreover, because of the descriptive nature of this study, the functional roles of identified mutations within the context of endometriosis remain unclear and causality cannot be established. WIDER IMPLICATIONS OF THE FINDINGS: The alterations we report may be important in driving the growth and survival of endometriosis in ectopic regions of the body. Given the frequency of mutation in surgically displaced endometrium (IE), examination of similar somatic events in eutopic endometrium, as well as clinically annotated cases of other forms of endometriosis, in particular endometriomas that are most commonly linked to malignancy, is warranted. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by a Canadian Cancer Society Impact Grant [701603, PI Huntsman], Canadian Institutes of Health Research Transitional Open Operating Grant [MOP-142273, PI Yong], the Canadian Institutes of Health Research Foundation Grant [FDN-154290, PI Huntsman], the Canadian Institutes of Health Research Project Grant [PJT-156084, PIs Yong and Anglesio], and the Janet D. Cottrelle Foundation through the BC Cancer Foundation [PI Huntsman]. D.G. Huntsman is a co-founder and shareholder of Contextual Genomics Inc., a for profit company that provides clinical reporting to assist in cancer patient treatment. R. Aguirre-Hernandez, J. Khattra and L.M. Prentice have a patent MOLECULAR QUALITY ASSURANCE METHODS FOR USE IN SEQUENCING pending and are current (or former) employees of Contextual Genomics Inc. The remaining authors have no competing interests to declare. TRIAL REGISTRATION NUMBER: Not applicable.


Assuntos
Biomarcadores Tumorais/genética , Carcinogênese/genética , Endometriose/patologia , Procedimentos Cirúrgicos em Ginecologia/efeitos adversos , Neoplasias/genética , Adulto , Biomarcadores Tumorais/metabolismo , Canadá , Progressão da Doença , Endometriose/etiologia , Endométrio/patologia , Endométrio/cirurgia , Feminino , Alemanha , Humanos , Doença Iatrogênica , Pessoa de Meia-Idade , Mutação , Neoplasias/patologia , Países Baixos , Estudos Retrospectivos , Transdução de Sinais/genética
8.
Rev Sci Instrum ; 85(4): 044101, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24784629

RESUMO

High abundances of iodine monoxide (IO) are known to exist and to participate in local photochemistry of the marine boundary layer. Of particular interest are the roles IO plays in the formation of new particles in coastal marine environments and in depletion episodes of ozone and mercury in the Arctic polar spring. This paper describes a ground-based instrument that measures IO at mixing ratios less than one part in 10(12). The IO radical is measured by detecting laser-induced fluorescence at wavelengths longer that 500 nm. Tunable visible light is used to pump the A(2)Π3/2 (v(') = 2) ← X(2)Π3/2 (v(″) = 0) transition of IO near 445 nm. The laser light is produced by a solid-state, Nd:YAG-pumped Ti:Sapphire laser at 5 kHz repetition rate. The laser-induced fluorescence instrument performs reliably with very high signal-to-noise ratios (>10) achieved in short integration times (<1 min). The observations from a validation deployment to the Shoals Marine Lab on Appledore Island, ME are presented and are broadly consistent with in situ observations from European Coastal Sites. Mixing ratios ranged from the instrumental detection limit (<1 pptv) to 10 pptv. These data represent the first in situ point measurements of IO in North America.


Assuntos
Fluorescência , Radicais Livres/análise , Compostos de Iodo/análise , Lasers , Óxidos/análise
9.
Mol Reprod Dev ; 60(4): 433-8, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11746953

RESUMO

The introduction of mammalian artificial chromosomes (ACs) into zygotes represents an alternative, more predictive technology for the production of recombinant proteins in transgenic animals. The aim of these experiments was to examine the effects of artificial chromosome microinjection into bovine pronuclei on embryo development and reporter gene expression. Bovine oocytes aspirated from 2-5 mm size follicles were matured in vitro for 22 hr. Mature oocytes were fertilized in vitro with frozen- thawed bull spermatozoa. Artificial chromosome carrying either beta-galactosidase (Lac-Z) gene or green fluorescence protein (GFP) gene were isolated by flow cytometry. A single chromosome was microinjected into one of the two pronuclei of bovine zygotes. Sham injected zygotes served as controls. Injected zygotes were cultured in G 1.2 medium for 7 days. Hatched blastocysts were cultured on blocked STO cell feeder layer for attachment and outgrowth of ICM and trophectoderm cells. The results showed a high zygote survival rate following LacZ-ACs microinjection (74%). However, the blastocyst development rate after 7 days of culture was significantly lower than that of sham injected zygotes (7.5 vs. 22%). Embryonic cells positive for Lac-Z gene were detected by PCR in three of nine outgrowth colonies. In addition, GFP gene expression was observed in 15 out of 85 (18%) embryos at the arrested 2-cell stage to blastocyst stage. Six blastocysts successfully outgrew, three outgrowths were GFP positive for up to 3 weeks in culture. We conclude that the methodology for artificial chromosome delivery into bovine zygotes could lead to viable blastocyst development, and reporter gene expression could be sustained during pre-implantation development.


Assuntos
Núcleo Celular/genética , Cromossomos Artificiais de Mamíferos/genética , Expressão Gênica , Genes Reporter/genética , Zigoto/citologia , Zigoto/metabolismo , Animais , Blastocisto/citologia , Blastocisto/metabolismo , Bovinos , Feminino , Fertilização , Citometria de Fluxo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Fluorescência Verde , Óperon Lac/genética , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Masculino , Microinjeções , Taxa de Sobrevida , Zigoto/crescimento & desenvolvimento
10.
J Immunol ; 166(10): 6367-75, 2001 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11342661

RESUMO

Granuloma formation is a form of delayed-type hypersensitivity requiring CD4(+) T cells. Granulomas control the growth and dissemination of pathogens, preventing host inflammation from harming surrounding tissues. Using a murine model of Mycobacterium bovis strain bacillus Calmette-Guérin (BCG) infection we studied the extent of T cell heterogeneity present in liver granulomas. We demonstrate that the TCR repertoire of granuloma-infiltrating T cells is very diverse even at the single-granuloma level, suggesting that before granuloma closure, a large number of different T cells are recruited to the lesion. At the same time, the TCR repertoire is selected, because AND TCR transgenic T cells (Valpha11/Vbeta3 anti-pigeon cytochrome c) are preferentially excluded from granulomas of BCG-infected AND mice, and cells expressing secondary endemic Vbeta-chains are enriched among AND cells homing to granulomas. Next, we addressed whether TCR heterogeneity is required for effective granuloma formation. We infected 5CC7/recombinase-activating gene 2(-/-) mice with recombinant BCG that express pigeon cytochrome c peptide in a mycobacterial 19-kDa bacterial surface lipoprotein. A CD4(+) T cell with a single specificity in the absence of CD8(+) T cells is sufficient to form granulomas and adequately control bacteria. Our study shows that expanded monoclonal T cell populations can be protective in mycobacterial infection.


Assuntos
Granuloma/imunologia , Granuloma/microbiologia , Fígado/imunologia , Fígado/microbiologia , Infecções por Mycobacterium/imunologia , Mycobacterium bovis/imunologia , Receptores de Antígenos de Linfócitos T/biossíntese , Subpopulações de Linfócitos T/imunologia , Animais , Movimento Celular/imunologia , Células Clonais , Epitopos de Linfócito T/fisiologia , Granuloma/genética , Granuloma/patologia , Imunofenotipagem , Fígado/patologia , Ativação Linfocitária/genética , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Infecções por Mycobacterium/genética , Infecções por Mycobacterium/microbiologia , Infecções por Mycobacterium/patologia , Receptores de Antígenos de Linfócitos T/genética , Baço/imunologia , Baço/microbiologia , Baço/patologia , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/patologia
11.
Chromosome Res ; 8(3): 183-91, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10841045

RESUMO

We have generated transgenic mice by pronuclear microinjection of a murine satellite DNA-based artificial chromosome (SATAC). As 50% of the founder progeny were SATAC-positive, this demonstrates that SATAC transmission through the germline had occurred. FISH analyses of metaphase chromosomes from mitogen-activated peripheral blood lymphocytes from both the founder and progeny revealed that the SATAC was maintained as a discrete chromosome and that it had not integrated into an endogenous chromosome. To our knowledge, this is the first report of the germline transmission of a genetically engineered mammalian artificial chromosome within transgenic animals generated through pronuclear microinjection. We have also shown that murine SATACs can be similarly introduced into bovine embryos. The use of embryo microinjection to generate transgenic mammals carrying genetically engineered chromosomes provides a novel method by which the unique advantages of chromosome-based gene delivery systems can be exploited.


Assuntos
Núcleo Celular/genética , Cromossomos/genética , DNA Satélite/genética , Técnicas de Transferência de Genes , Oócitos/citologia , Animais , Bovinos , Embrião de Mamíferos , Feminino , Citometria de Fluxo , Hibridização in Situ Fluorescente , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Transgênicos , Microinjeções , Reação em Cadeia da Polimerase
13.
J Biol Chem ; 268(9): 6622-8, 1993 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-8454633

RESUMO

The polymerase chain reaction was used to amplify protein tyrosine phosphatase (PTPase)-related cDNA from a template of total RNA isolated from human skeletal muscle. A novel PTPase, which we term PTP-PEST, was detected by this method. The polymerase chain reaction fragment was used to screen two different HeLa cell libraries to obtain full length cDNA clones. The cDNA predicts a protein of 510 amino acids, approximately 60 kDa, that does not contain an obvious signal sequence or transmembrane segment suggesting it is a nonreceptor type enzyme. The PTPase domain is located in the N-terminal portion of the molecule and displays approximately 35% identity to other members of this family of enzymes. The C-terminal segment is rich in Pro, Glu, Asp, Ser, and Thr residues, possessing features of PEST motifs which have previously been identified in proteins with very short intracellular half-lives. The protein was expressed in Escherichia coli as a fusion product with glutathione S-transferase. Intrinsic activity was demonstrated in vitro against a variety of phosphotyrosine-containing substrates including BIRK, the autophosphorylated cytoplasmic kinase domain of the insulin receptor beta subunit. It did not dephosphorylate phosphoseryl-phosphorylase a. PTP-PEST mRNA is broadly distributed in a variety of cell lines. Stimulation of human rhabdomyosarcoma A204 cells, a transformed muscle line, with insulin led to an approximately 4-fold induction of PTP-PEST mRNA within 36 h.


Assuntos
Proteínas Tirosina Fosfatases/genética , Adulto , Sequência de Aminoácidos , Sequência de Bases , Northern Blotting , Clonagem Molecular , DNA , Células HeLa , Humanos , Masculino , Dados de Sequência Molecular , Fosforilação , Proteínas Tirosina Fosfatases/metabolismo , Homologia de Sequência de Aminoácidos
14.
J Rheumatol ; 17(6): 849-51, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2388212

RESUMO

A patient with a Staphylococcus aureus infection of the subacromial/subdeltoid bursa is described. Instillation of radiocontrast dye into the purulent cavity provided evidence that the infection was localized to the subacromial/subdeltoid bursa. The use of bursography/arthrography to define the site and extent of shoulder infections may help to determine the optimal duration of antibiotic therapy and the prognosis for cartilage and/or bone destruction.


Assuntos
Bolsa Sinovial/microbiologia , Infecções Estafilocócicas/patologia , Acrômio , Adulto , Bolsa Sinovial/diagnóstico por imagem , Bolsa Sinovial/patologia , Diagnóstico Diferencial , Humanos , Artropatias/diagnóstico , Artropatias/tratamento farmacológico , Artropatias/patologia , Masculino , Nafcilina/uso terapêutico , Prognóstico , Radiografia , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/tratamento farmacológico
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