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1.
Cell ; 160(3): 433-46, 2015 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-25635457

RESUMO

Antibodies developed during HIV-1 infection lose efficacy as the viral spike mutates. We postulated that anti-HIV-1 antibodies primarily bind monovalently because HIV's low spike density impedes bivalent binding through inter-spike crosslinking, and the spike structure prohibits bivalent binding through intra-spike crosslinking. Monovalent binding reduces avidity and potency, thus expanding the range of mutations permitting antibody evasion. To test this idea, we engineered antibody-based molecules capable of bivalent binding through intra-spike crosslinking. We used DNA as a "molecular ruler" to measure intra-epitope distances on virion-bound spikes and construct intra-spike crosslinking molecules. Optimal bivalent reagents exhibited up to 2.5 orders of magnitude increased potency (>100-fold average increases across virus panels) and identified conformational states of virion-bound spikes. The demonstration that intra-spike crosslinking lowers the concentration of antibodies required for neutralization supports the hypothesis that low spike densities facilitate antibody evasion and the use of molecules capable of intra-spike crosslinking for therapy or passive protection.


Assuntos
Anticorpos Neutralizantes/química , Anticorpos Anti-HIV/química , HIV-1 , Fragmentos Fab das Imunoglobulinas/química , Imunoglobulina G/química , Anticorpos Neutralizantes/imunologia , Reagentes de Ligações Cruzadas/metabolismo , Cristalografia por Raios X , Epitopos , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/imunologia , Imunoglobulina G/imunologia , Engenharia de Proteínas
2.
Proteomics ; 24(17): e2300385, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39001627

RESUMO

The mzIdentML data format, originally developed by the Proteomics Standards Initiative in 2011, is the open XML data standard for peptide and protein identification results coming from mass spectrometry. We present mzIdentML version 1.3.0, which introduces new functionality and support for additional use cases. First of all, a new mechanism for encoding identifications based on multiple spectra has been introduced. Furthermore, the main mzIdentML specification document can now be supplemented by extension documents which provide further guidance for encoding specific use cases for different proteomics subfields. One extension document has been added, covering additional use cases for the encoding of crosslinked peptide identifications. The ability to add extension documents facilitates keeping the mzIdentML standard up to date with advances in the proteomics field, without having to change the main specification document. The crosslinking extension document provides further explanation of the crosslinking use cases already supported in mzIdentML version 1.2.0, and provides support for encoding additional scenarios that are critical to reflect developments in the crosslinking field and facilitate its integration in structural biology. These are: (i) support for cleavable crosslinkers, (ii) support for internally linked peptides, (iii) support for noncovalently associated peptides, and (iv) improved support for encoding scores and the corresponding thresholds.


Assuntos
Reagentes de Ligações Cruzadas , Espectrometria de Massas , Proteômica , Proteômica/métodos , Reagentes de Ligações Cruzadas/química , Espectrometria de Massas/métodos , Peptídeos/química , Peptídeos/análise , Bases de Dados de Proteínas , Software , Proteínas/química
3.
Nat Methods ; 18(7): 768-770, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34183830

RESUMO

Mass spectra provide the ultimate evidence to support the findings of mass spectrometry proteomics studies in publications, and it is therefore crucial to be able to trace the conclusions back to the spectra. The Universal Spectrum Identifier (USI) provides a standardized mechanism for encoding a virtual path to any mass spectrum contained in datasets deposited to public proteomics repositories. USI enables greater transparency of spectral evidence, with more than 1 billion USI identifications from over 3 billion spectra already available through ProteomeXchange repositories.


Assuntos
Bases de Dados de Proteínas , Espectrometria de Massas/métodos , Proteômica/métodos , Processamento de Sinais Assistido por Computador , Software , Algoritmos
4.
J Surg Res ; 300: 8-14, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38788482

RESUMO

INTRODUCTION: The shock index (SI) is a known predictor of unfavorable outcomes in trauma. This study seeks to examine and compare the SI values between geriatric patients and younger adults. METHODS: We conducted a retrospective study of the Trauma Quality Improvement Program database from 2017 to 2019. All patients≥ 25 y with injury severity score ≥ 16 were included. Age groups were defined as 25-44 y (group A), 45-64 y (group B), and ≥65 y (group C). SI was calculated for all patients. The primary outcome was mortality and secondary outcomes were need for blood transfusion and need for major surgical intervention (consisting angiography, exploratory laparotomy, and thoracotomy). RESULTS: A total of 244,943 patients were studied. The SI was highest in group A (0.82 ± 0.33) and lowest in group C (0.62 ± 0.30) (P < 0.001). Mortality rate of group C (17%) was significantly higher than group A (9.7%) and B (11.3%) (P < 0.001). In group A, each 0.1 increase in SI was associated with mortality (odds ratio [OR] = 1.079), need for blood transfusion (OR = 1.225) and need for major surgical intervention (OR = 1.347) (P < 0.001 for all). In group C, each 0.1 increase in SI was associated with mortality (OR = 1.126), need for blood transfusion (OR = 1.318), and need for major surgical intervention (OR = 1.648) (P < 0.001 for all). The area under the curve of SI was significantly higher in group C compared to other groups for needing a major surgical intervention and need for blood transfusion (P < 0.05 for both). CONCLUSIONS: These results highlight the significance of the SI as a valuable indicator in geriatric patients with severe trauma. The findings show that SI predicts outcomes in geriatrics more strongly than in younger counterparts.


Assuntos
Choque , Humanos , Estudos Retrospectivos , Pessoa de Meia-Idade , Masculino , Feminino , Idoso , Adulto , Fatores Etários , Choque/mortalidade , Choque/diagnóstico , Choque/terapia , Transfusão de Sangue/estatística & dados numéricos , Ferimentos e Lesões/mortalidade , Ferimentos e Lesões/terapia , Ferimentos e Lesões/diagnóstico , Escala de Gravidade do Ferimento , Prognóstico
5.
Mol Cell Proteomics ; 21(11): 100412, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36103992

RESUMO

Amino acid sequences of immunodominant domains of hemagglutinin (HA) on the surface of influenza A virus (IAV) evolve rapidly, producing viral variants. HA mediates receptor recognition, binding and cell entry, and serves as the target for IAV vaccines. Glycosylation, a post-translational modification that places large branched polysaccharide molecules on proteins, can modulate the function of HA and shield antigenic regions allowing for viral evasion from immune responses. Our previous work showed that subtle changes in the HA protein sequence can have a measurable change in glycosylation. Thus, being able to quantitatively measure glycosylation changes in variants is critical for understanding how HA function may change throughout viral evolution. Moreover, understanding quantitatively how the choice of viral expression systems affects glycosylation can help in the process of vaccine design and manufacture. Although IAV vaccines are most commonly expressed in chicken eggs, cell-based vaccines have many advantages, and the adoption of more cell-based vaccines would be an important step in mitigating seasonal influenza and protecting against future pandemics. Here, we have investigated the use of data-independent acquisition (DIA) mass spectrometry for quantitative glycoproteomics. We found that DIA improved the sensitivity of glycopeptide detection for four variants of A/Switzerland/9715293/2013 (H3N2): WT and mutant, each expressed in embryonated chicken eggs and Madin-Darby canine kidney cells. We used the Tanimoto similarity metric to quantify changes in glycosylation between WT and mutant and between egg-expressed and cell-expressed virus. Our DIA site-specific glycosylation similarity comparison of WT and mutant expressed in eggs confirmed our previous analysis while achieving greater depth of coverage. We found that sequence variations and changing viral expression systems affected distinct glycosylation sites of HA. Our methods can be applied to track glycosylation changes in circulating IAV variants to bolster genomic surveillance already being done, for a more complete understanding of IAV evolution.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A , Vacinas contra Influenza , Influenza Humana , Cães , Animais , Humanos , Vírus da Influenza A/metabolismo , Glicosilação , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Vírus da Influenza A Subtipo H3N2 , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/metabolismo , Espectrometria de Massas
6.
Skeletal Radiol ; 53(9): 1711-1725, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38969781

RESUMO

Computed tomography (CT) is a common modality employed for musculoskeletal imaging. Conventional CT techniques are useful for the assessment of trauma in detection, characterization and surgical planning of complex fractures. CT arthrography can depict internal derangement lesions and impact medical decision making of orthopedic providers. In oncology, CT can have a role in the characterization of bone tumors and may elucidate soft tissue mineralization patterns. Several advances in CT technology have led to a variety of acquisition techniques with distinct clinical applications. These include four-dimensional CT, which allows examination of joints during motion; cone-beam CT, which allows examination during physiological weight-bearing conditions; dual-energy CT, which allows material decomposition useful in musculoskeletal deposition disorders (e.g., gout) and bone marrow edema detection; and photon-counting CT, which provides increased spatial resolution, decreased radiation, and material decomposition compared to standard multi-detector CT systems due to its ability to directly translate X-ray photon energies into electrical signals. Advanced acquisition techniques provide higher spatial resolution scans capable of enhanced bony microarchitecture and bone mineral density assessment. Together, these CT acquisition techniques will continue to play a substantial role in the practices of orthopedics, rheumatology, metabolic bone, oncology, and interventional radiology.


Assuntos
Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Doenças Musculoesqueléticas/diagnóstico por imagem , Sistema Musculoesquelético/diagnóstico por imagem
7.
J Assist Reprod Genet ; 41(8): 2021-2036, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38814543

RESUMO

PURPOSE: Determine if the gene expression profiles of ovarian support cells (OSCs) and cumulus-free oocytes are bidirectionally influenced by co-culture during in vitro maturation (IVM). METHODS: Fertility patients aged 25 to 45 years old undergoing conventional ovarian stimulation donated denuded immature oocytes for research. Oocytes were randomly allocated to either OSC-IVM culture (intervention) or Media-IVM culture (control) for 24-28 h. The OSC-IVM culture condition was composed of 100,000 OSCs in suspension culture with human chorionic gonadotropin (hCG), recombinant follicle stimulating hormone (rFSH), androstenedione, and doxycycline supplementation. The Media-IVM control lacked OSCs and contained the same supplementation. A limited set of in vivo matured MII oocytes were donated for comparative evaluation. Endpoints consisted of MII formation rate, morphological and spindle quality assessment, and gene expression analysis compared to in vitro and in vivo controls. RESULTS: OSC-IVM resulted in a statistically significant improvement in MII formation rate compared to the Media-IVM control, with no apparent effect on morphology or spindle assembly. OSC-IVM MII oocytes displayed a closer transcriptomic maturity signature to IVF-MII controls than Media-IVM control MII oocytes. The gene expression profile of OSCs was modulated in the presence of oocytes, displaying culture- and time-dependent differential gene expression during IVM. CONCLUSION: The OSC-IVM platform is a novel tool for rescue maturation of human oocytes, yielding oocytes with improved nuclear maturation and a closer transcriptomic resemblance to in vivo matured oocytes, indicating a potential enhancement in oocyte cytoplasmic maturation. These improvements on oocyte quality after OSC-IVM are possibly occurring through bidirectional crosstalk of cumulus-free oocytes and ovarian support cells.


Assuntos
Técnicas de Maturação in Vitro de Oócitos , Oócitos , Indução da Ovulação , Transcriptoma , Humanos , Feminino , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Oócitos/efeitos dos fármacos , Técnicas de Maturação in Vitro de Oócitos/métodos , Adulto , Indução da Ovulação/métodos , Transcriptoma/genética , Células do Cúmulo/metabolismo , Células do Cúmulo/efeitos dos fármacos , Fertilização in vitro/métodos , Gonadotropina Coriônica/farmacologia , Técnicas de Cocultura , Pessoa de Meia-Idade , Hormônio Foliculoestimulante/farmacologia , Hormônio Foliculoestimulante/genética , Ovário/metabolismo
8.
J Proteome Res ; 22(2): 287-301, 2023 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-36626722

RESUMO

The Human Proteome Organization (HUPO) Proteomics Standards Initiative (PSI) has been successfully developing guidelines, data formats, and controlled vocabularies (CVs) for the proteomics community and other fields supported by mass spectrometry since its inception 20 years ago. Here we describe the general operation of the PSI, including its leadership, working groups, yearly workshops, and the document process by which proposals are thoroughly and publicly reviewed in order to be ratified as PSI standards. We briefly describe the current state of the many existing PSI standards, some of which remain the same as when originally developed, some of which have undergone subsequent revisions, and some of which have become obsolete. Then the set of proposals currently being developed are described, with an open call to the community for participation in the forging of the next generation of standards. Finally, we describe some synergies and collaborations with other organizations and look to the future in how the PSI will continue to promote the open sharing of data and thus accelerate the progress of the field of proteomics.


Assuntos
Proteoma , Proteômica , Humanos , Padrões de Referência , Vocabulário Controlado , Espectrometria de Massas , Bases de Dados de Proteínas
9.
Radiology ; 308(2): e230344, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37606571

RESUMO

CT is one of the most widely used modalities for musculoskeletal imaging. Recent advancements in the field include the introduction of four-dimensional CT, which captures a CT image during motion; cone-beam CT, which uses flat-panel detectors to capture the lower extremities in weight-bearing mode; and dual-energy CT, which operates at two different x-ray potentials to improve the contrast resolution to facilitate the assessment of tissue material compositions such as tophaceous gout deposits and bone marrow edema. Most recently, photon-counting CT (PCCT) has been introduced. PCCT is a technique that uses photon-counting detectors to produce an image with higher spatial and contrast resolution than conventional multidetector CT systems. In addition, postprocessing techniques such as three-dimensional printing and cinematic rendering have used CT data to improve the generation of both physical and digital anatomic models. Last, advancements in the application of artificial intelligence to CT imaging have enabled the automatic evaluation of musculoskeletal pathologies. In this review, the authors discuss the current state of the above CT technologies, their respective advantages and disadvantages, and their projected future directions for various musculoskeletal applications.


Assuntos
Inteligência Artificial , Tomografia Computadorizada de Feixe Cônico , Humanos , Tomografia Computadorizada Quadridimensional , Extremidade Inferior , Movimento (Física)
10.
Hum Reprod ; 38(12): 2456-2469, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37815487

RESUMO

STUDY QUESTION: Can in vitro maturation (IVM) and developmental competence of human oocytes be improved by co-culture with ovarian support cells (OSCs) derived from human-induced pluripotent stem cells (hiPSCs)? SUMMARY ANSWER: OSC-IVM significantly improves the rates of metaphase II (MII) formation and euploid Day 5 or 6 blastocyst formation, when compared to a commercially available IVM system. WHAT IS KNOWN ALREADY: IVM has historically shown highly variable performance in maturing oocytes and generating oocytes with strong developmental capacity, while limited studies have shown a positive benefit of primary granulosa cell co-culture for IVM. We recently reported the development of OSCs generated from hiPSCs that recapitulate dynamic ovarian function in vitro. STUDY DESIGN, SIZE, DURATION: The study was designed as a basic science study, using randomized sibling oocyte specimen allocation. Using pilot study data, a prospective sample size of 20 donors or at least 65 oocytes per condition were used for subsequent experiments. A total of 67 oocyte donors were recruited to undergo abbreviated gonadotropin stimulation with or without hCG triggers and retrieved cumulus-oocyte complexes (COCs) were allocated between the OSC-IVM or control conditions (fetal-like OSC (FOSC)-IVM or media-only IVM) in three independent experimental design formats. The total study duration was 1 April 2022 to 1 July 2023. PARTICIPANTS/MATERIALS, SETTING, METHODS: Oocyte donors between the ages of 19 and 37 years were recruited for retrieval after informed consent, with assessment of anti-Mullerian hormone, antral follicle count, age, BMI and ovarian pathology used for inclusion and exclusion criteria. In experiment 1, 27 oocyte donors were recruited, in experiment 2, 23 oocyte donors were recruited, and in experiment 3, 17 oocyte donors and 3 sperm donors were recruited. The OSC-IVM culture condition was composed of 100 000 OSCs in suspension culture with hCG, recombinant FSH, androstenedione, and doxycycline supplementation. IVM controls lacked OSCs and contained either the same supplementation, FSH and hCG only (a commercial IVM control), or FOSCs with the same supplementation (Media control). Experiment 1 compared OSC-IVM, FOSC-IVM, and a Media control, while experiments 2 and 3 compared OSC-IVM and a commercial IVM control. Primary endpoints in the first two experiments were the MII formation (i.e. maturation) rate and morphological quality assessment. In the third experiment, the fertilization and embryo formation rates were assessed with genetic testing for aneuploidy and epigenetic quality in blastocysts. MAIN RESULTS AND THE ROLE OF CHANCE: We observed a statistically significant improvement (∼1.5×) in maturation outcomes for oocytes that underwent IVM with OSCs compared to control Media-IVM and FOSC-IVM in experiment 1. More specifically, the OSC-IVM group yielded a MII formation rate of 68% ± 6.83% SEM versus 46% ± 8.51% SEM in the Media control (P = 0.02592, unpaired t-test). FOSC-IVM yielded a 51% ± 9.23% SEM MII formation rate which did not significantly differ from the media control (P = 0.77 unpaired t-test). Additionally, OSC-IVM yielded a statistically significant ∼1.6× higher average MII formation rate at 68% ± 6.74% when compared to 43% ± 7.90% in the commercially available IVM control condition (P = 0.0349, paired t-test) in experiment 2. Oocyte morphological quality between OSC-IVM and the controls did not significantly differ. In experiment 3, OSC-IVM oocytes demonstrated a statistically significant improvement in Day 5 or 6 euploid blastocyst formation per COC compared to the commercial IVM control (25% ± 7.47% vs 11% ± 3.82%, P = 0.0349 logistic regression). Also in experiment 3, the OSC-treated oocytes generated blastocysts with similar global and germline differentially methylated region epigenetic profiles compared commercial IVM controls or blastocysts after either conventional ovarian stimulation. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: While the findings of this study are compelling, the cohort size remains limited and was powered on preliminary pilot studies, and the basic research nature of the study limits generalizability compared to randomized control trials. Additionally, use of hCG-triggered cycles results in a heterogenous oocyte cohort, and potential differences in the underlying maturation state of oocytes pre-IVM may limit or bias findings. Further research is needed to clarify and characterize the precise mechanism of action of the OSC-IVM system. Further research is also needed to establish whether these embryos are capable of implantation and further development, a key indication of their clinical utility. WIDER IMPLICATIONS OF THE FINDINGS: Together, these findings demonstrate a novel approach to IVM with broad applicability to modern ART practice. The controls used in this study are in line with and have produced similar to findings to those in the literature, and the outcome of this study supports findings from previous co-culture studies that found benefits of primary granulosa cells on IVM outcomes. The OSC-IVM system shows promise as a highly flexible IVM approach that can complement a broad range of stimulation styles and patient populations. Particularly for patients who cannot or prefer not to undergo conventional gonadotropin stimulation, OSC-IVM may present a viable path for obtaining developmentally competent, mature oocytes. STUDY FUNDING/COMPETING INTEREST(S): A.D.N., A.B.F., A.G., B.P., C.A., C.C.K., F.B., G.R., K.S.P., K.W., M.M., P.C., S.P., and M.-J.F.-G. are shareholders in the for-profit biotechnology company Gameto Inc. P.R.J.F. declares paid consultancy for Gameto Inc. P.C. also declares paid consultancy for the Scientific Advisory Board for Gameto Inc. D.H.M. has received consulting services from Granata Bio, Sanford Fertility and Reproductive Medicine, Gameto, and Buffalo IVF, and travel support from the Upper Egypt Assisted Reproduction Society. C.C.K., S.P., M.M., A.G., B.P., K.S.P., G.R., and A.D.N. are listed on a patent covering the use of OSCs for IVM: U.S. Provisional Patent Application No. 63/492,210. Additionally, C.C.K. and K.W. are listed on three patents covering the use of OSCs for IVM: U.S. Patent Application No. 17/846,725, U.S Patent Application No. 17/846,845, and International Patent Application No.: PCT/US2023/026012. C.C.K., M.P.S., and P.C. additionally are listed on three patents for the transcription factor-directed production of granulosa-like cells from stem cells: International Patent Application No.: PCT/US2023/065140, U.S. Provisional Application No. 63/326,640, and U.S. Provisional Application No. 63/444,108. The remaining authors have no conflicts of interest to declare.


Assuntos
Técnicas de Maturação in Vitro de Oócitos , Células-Tronco Pluripotentes Induzidas , Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Técnicas de Cocultura , Hormônio Foliculoestimulante/metabolismo , Gonadotropinas/metabolismo , Técnicas de Maturação in Vitro de Oócitos/métodos , Oócitos/metabolismo , Projetos Piloto , Estudos Prospectivos , Sêmen
11.
Eur Radiol ; 2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-37951855

RESUMO

BACKGROUND: Pneumonia-related hospitalization may be associated with advanced skeletal muscle loss due to aging (i.e., sarcopenia) or chronic illnesses (i.e., cachexia). Early detection of muscle loss may now be feasible using deep-learning algorithms applied on conventional chest CT. OBJECTIVES: To implement a fully automated deep-learning algorithm for pectoralis muscle measures from conventional chest CT and investigate longitudinal associations between these measures and incident pneumonia hospitalization according to Chronic Obstructive Pulmonary Disease (COPD) status. MATERIALS AND METHODS: This analysis from the Multi-Ethnic Study of Atherosclerosis included participants with available chest CT examinations between 2010 and 2012. We implemented pectoralis muscle composition measures from a fully automated deep-learning algorithm (Mask R-CNN, built on the Faster Region Proposal Network (R-) Convolutional Neural Network (CNN) with an extension for mask identification) for two-dimensional segmentation. Associations between CT-derived measures and incident pneumonia hospitalizations were evaluated using Cox proportional hazards models adjusted for multiple confounders which include but are not limited to age, sex, race, smoking, BMI, physical activity, and forced-expiratory-volume-at-1 s-to-functional-vital-capacity ratio. Stratification analyses were conducted based on baseline COPD status. RESULTS: This study included 2595 participants (51% female; median age: 68 (IQR: 61, 76)) CT examinations for whom we implemented deep learning-derived measures for longitudinal analyses. Eighty-six incident pneumonia hospitalizations occurred during a median 6.67-year follow-up. Overall, pectoralis muscle composition measures did not predict incident pneumonia. However, in fully-adjusted models, only among participants with COPD (N = 507), CT measures like extramyocellular fat index (hazard ratio: 1.98, 95% CI: 1.22, 3.21, p value: 0.02), were independently associated with incident pneumonia. CONCLUSION: Reliable deep learning-derived pectoralis muscle measures could predict incident pneumonia hospitalization only among participants with known COPD. CLINICAL RELEVANCE STATEMENT: Pectoralis muscle measures obtainable at zero additional cost or radiation exposure from any chest CT may have independent predictive value for clinical outcomes in chronic obstructive pulmonary disease patients. KEY POINTS: •Identification of independent and modifiable risk factors of pneumonia can have important clinical impact on patients with chronic obstructive pulmonary disease. •Opportunistic CT measures of adipose tissue within pectoralis muscles using deep-learning algorithms can be quickly obtainable at zero additional cost or radiation exposure. •Deep learning-derived pectoralis muscle measurements of intermuscular fat and its subcomponents are independently associated with subsequent incident pneumonia hospitalization.

12.
Mol Cell Proteomics ; 20: 100093, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33992776

RESUMO

The sulfated glycosaminoglycans (GAGs) are long, linear polysaccharide chains that are typically found as the glycan portion of proteoglycans. These GAGs are characterized by repeating disaccharide units with variable sulfation and acetylation patterns along the chain. GAG length and modification patterns have profound impacts on growth factor signaling mechanisms central to numerous physiological processes. Electron activated dissociation tandem mass spectrometry is a very effective technique for assigning the structures of GAG saccharides; however, manual interpretation of the resulting complex tandem mass spectra is a difficult and time-consuming process that drives the development of computational methods for accurate and efficient sequencing. We have recently published GAGfinder, the first peak picking and elemental composition assignment algorithm specifically designed for GAG tandem mass spectra. Here, we present GAGrank, a novel network-based method for determining GAG structure using information extracted from tandem mass spectra using GAGfinder. GAGrank is based on Google's PageRank algorithm for ranking websites for search engine output. In particular, it is an implementation of BiRank, an extension of PageRank for bipartite networks. In our implementation, the two partitions comprise every possible sequence for a given GAG composition and the tandem MS fragments found using GAGfinder. Sequences are given a higher ranking if they link to many important fragments. Using the simulated annealing probabilistic optimization technique, we optimized GAGrank's parameters on ten training sequences. We then validated GAGrank's performance on three validation sequences. We also demonstrated GAGrank's ability to sequence isomeric mixtures using two mixtures at five different ratios.


Assuntos
Glicosaminoglicanos/química , Software , Algoritmos , Modelos Teóricos , Espectrometria de Massas em Tandem
13.
J Proteome Res ; 21(4): 1189-1195, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35290070

RESUMO

It is important for the proteomics community to have a standardized manner to represent all possible variations of a protein or peptide primary sequence, including natural, chemically induced, and artifactual modifications. The Human Proteome Organization Proteomics Standards Initiative in collaboration with several members of the Consortium for Top-Down Proteomics (CTDP) has developed a standard notation called ProForma 2.0, which is a substantial extension of the original ProForma notation developed by the CTDP. ProForma 2.0 aims to unify the representation of proteoforms and peptidoforms. ProForma 2.0 supports use cases needed for bottom-up and middle-/top-down proteomics approaches and allows the encoding of highly modified proteins and peptides using a human- and machine-readable string. ProForma 2.0 can be used to represent protein modifications in a specified or ambiguous location, designated by mass shifts, chemical formulas, or controlled vocabulary terms, including cross-links (natural and chemical) and atomic isotopes. Notational conventions are based on public controlled vocabularies and ontologies. The most up-to-date full specification document and information about software implementations are available at http://psidev.info/proforma.


Assuntos
Proteoma , Proteômica , Humanos , Processamento de Proteína Pós-Traducional , Proteoma/genética , Padrões de Referência , Software
14.
Surg Technol Int ; 412022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-36041078

RESUMO

INTRODUCTION: Using direct peritoneal resuscitation (DPR) as an adjunct when managing patients undergoing damage control laparotomy (DCL) shows promising results. We report our initial experience in utilizing DPR when managing patients who underwent DCL for emergent surgery at the index operation. MATERIALS AND METHODS: We prospectively collected data on 37 patients between August 2020 to October 2021 who underwent DCL with open abdomens after the index operation and utilized DPR. DPR was performed using peritoneal lavage with DIANEAL PD-2-D 2.5% Ca 3.5 mEq/L at a rate of 400ml/hour. Patients' physiological scores and clinical outcomes were evaluated. RESULTS: 86% required DCL and DPR due to septic abdomen/bowel ischemia. The median (interquartile range [IQR]) age was 62 years (53-70); 62% were male, and median (IQR) body mass index was 30.0kg/m2 (25.5-38.4). On DPR initiation, median (IQR) APACHE-IV score was 48 (33-64) and median (IQR) Acute Physiology Score (APS) was 31 (18-54). After initiation, median (IQR) APACHE-IV score and median (IQR) APS were 39 (21-62) and 19 (11-56), respectively, and both showed significant improvement in survivors (p<0.05). Median (IQR) DPR duration was four days (2-8) and primary abdominal closure was achieved in 30 patients (81%). There were eight mortalities (21.6%) within 30 days postoperatively, of which seven were within 3-24 days due to uncontrolled sepsis/multiple organ failure. The most frequent complication was surgical-site infection recorded in 12 patients (32%). Twenty-four patients (67%) were discharged home/transferred to a rehab center/nursing home. CONCLUSION: DPR application showed significant improvement of APACHE-IV score and APS in patients with peritonitis/septic abdomen.

15.
Medicina (Kaunas) ; 58(12)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36557055

RESUMO

Background and Objectives: To achieve pregnancy, it is highly beneficial to identify the time of ovulation as well as the greater period of fertile days during which sperm may survive leading up to ovulation. Confirming successful ovulation is also critical to accurately diagnose ovulatory disorders. Ovulation predictor kits, fertility monitors, and tracking apps are all available to assist with detecting ovulation, but often fall short. They may not detect the full fertile window, provide accurate or real-time information, or are simply expensive and impractical. Finally, few over-the-counter products provide information to women about their ovarian reserve and future fertility. Therefore, there is a need for an easy, over-the-counter, at-home quantitative hormone monitoring system that assesses ovarian reserve, predicts the entire fertile window, and can screen for ovulatory disorders. Materials and Methods: Proov Complete is a four-in-one at-home multihormone testing system that utilizes lateral flow assay test strips paired with the free Proov Insight App to guide testing of four hormones-FSH, E1G, LH, and PdG-across the woman's cycle. In a pilot study, 40 women (including 16 with a fertility-related diagnosis or using fertility treatments) used Complete for one cycle. Results: Here, we demonstrate that Proov Complete can accurately and sensitively predict ovarian reserve, detect up to 6 fertile days and confirm if ovulation was successful, in one easy-to-use kit. Ovulation was confirmed in 38 cycles with a detectable PdG rise. An average of 5.3 fertile days (from E1G rise to PdG rise) were detected, with an average of 2.7 days prior to LH surge. Ovulation was confirmed via PdG rise an average of 2.6 days following the LH surge. While 38/40 women had a PdG rise, only 22 had a sustained PdG level above 5 µg/mL throughout the critical implantation window, indicating ovulatory dysfunction in 16 women. Conclusions: Proov Complete can detect the entire fertile window of up to 6 fertile days and confirm ovulation, while also providing information on ovarian reserve and guidance to clinicians and patients.


Assuntos
Ovulação , Sêmen , Masculino , Feminino , Humanos , Projetos Piloto , Fertilidade , Hormônio Luteinizante
16.
Anal Bioanal Chem ; 413(29): 7305-7318, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34635934

RESUMO

The spike protein of SARS-CoV-2, the virus responsible for the global pandemic of COVID-19, is an abundant, heavily glycosylated surface protein that plays a key role in receptor binding and host cell fusion, and is the focus of all current vaccine development efforts. Variants of concern are now circulating worldwide that exhibit mutations in the spike protein. Protein sequence and glycosylation variations of the spike may affect viral fitness, antigenicity, and immune evasion. Global surveillance of the virus currently involves genome sequencing, but tracking emerging variants should include quantitative measurement of changes in site-specific glycosylation as well. In this work, we used data-dependent acquisition (DDA) and data-independent acquisition (DIA) mass spectrometry to quantitatively characterize the five N-linked glycosylation sites of the glycoprotein standard alpha-1-acid glycoprotein (AGP), as well as the 22 sites of the SARS-CoV-2 spike protein. We found that DIA compared favorably to DDA in sensitivity, resulting in more assignments of low-abundance glycopeptides. However, the reproducibility across replicates of DIA-identified glycopeptides was lower than that of DDA, possibly due to the difficulty of reliably assigning low-abundance glycopeptides confidently. The differences in the data acquired between the two methods suggest that DIA outperforms DDA in terms of glycoprotein coverage but that overall performance is a balance of sensitivity, selectivity, and statistical confidence in glycoproteomics. We assert that these analytical and bioinformatics methods for assigning and quantifying glycoforms would benefit the process of tracking viral variants as well as for vaccine development.


Assuntos
Glicômica/métodos , Espectrometria de Massas/métodos , Proteômica/métodos , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/química , COVID-19/virologia , Glicosilação , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Glicoproteína da Espícula de Coronavírus/metabolismo
17.
World J Surg ; 45(5): 1323-1329, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33481083

RESUMO

BACKGROUND: To analyze and report on the changes in epidemiology traumatic causes of death in the USA. METHODS: Data were extracted from the annual National Vital Statistics Reports (2008-2017) from Center for Disease Control and analyzed for trends during the time period given. Generalized additive model was applied to evaluate the significance of trend using R software. RESULTS: Firearm deaths (39,790) and firearm death rate (12.2/100,000) in 2017 were the highest reported, and this increasing trend was significant (p < 0.001) the last ten years. Deaths from motor vehicle crash (MVC) and firearm homicides did not change significantly during the same time period. Firearm deaths were lower than MVC deaths by 21% (8,197/39,790) in 2008, but after 10 years, the difference was only 1% (458/40,231). Years of life lost from firearms is now higher than MVC. Suicides by firearm in 2017 were the highest reported at 23,854/39,773 (60%). In 2017, suicides by firearm victims were predominantly white 20,328/23,562 (85%), men 20,362/23,562 (86%), and the largest group was between the ages of 55-64. CONCLUSIONS: Death from firearms in the USA is increasing and endemic. They were the highest ever reported in 2017 by the CDC. While deaths from MVC used to be the main cause of traumatic death in the USA, deaths from firearms now almost equal it. Calculated years of life lost from firearms is now more than from MVC. Most firearm deaths are not from homicides but are from suicides, and they are predominantly in white older males of the baby boomer generation (born 1946-1964).


Assuntos
Armas de Fogo , Suicídio , Ferimentos por Arma de Fogo , Acidentes de Trânsito , Causas de Morte , Homicídio , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos/epidemiologia
18.
Mol Cell Proteomics ; 18(3): 571-575, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30563850

RESUMO

mzML and mzIdentML are commonly used, powerful tools for representing mass spectrometry data and derived identification information. These formats are complex, requiring non-trivial logic to translate data into the appropriate representation. Most published implementations are tightly coupled to data structures. The most complete implementations are written in compiled languages that cannot expose the complete flexibility of the implementation to external programs or bindings. To our knowledge, there are no complete implementations for mzML or mzIdentML available to scripting languages like Python or R. We present psims, a library written in Python for writing mzML and mzIdentML. The library allows writing either XML format using built-in Python data structures. It includes a controlled vocabulary resolution system to simplify the encoding process and an identity tracking system to manage entity relationships. The source code is available at https://github.com/mobiusklein/psims, and through the Python Package Index as psims, licensed under the Apache 2 common license.


Assuntos
Proteômica/métodos , Humanos , Espectrometria de Massas , Linguagens de Programação , Vocabulário Controlado
19.
Mol Cell Proteomics ; 18(11): 2138-2148, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31471497

RESUMO

The most straightforward applications of proteomics database searching involve intracellular proteins. Although intracellular gene products number in the thousands, their well-defined post-translational modifications (PTMs) makes database searching practical. By contrast, cell surface and extracellular matrisome proteins pass through the secretory pathway where many become glycosylated, modulating their physicochemical properties, adhesive interactions, and diversifying their functions. Although matrisome proteins number only a few hundred, their high degree of complex glycosylation multiplies the number of theoretical proteoforms by orders of magnitude. Given that extracellular networks that mediate cell-cell and cell-pathogen interactions in physiology depend on glycosylation, it is important to characterize the proteomes, glycomes, and glycoproteomes of matrisome molecules that exist in a given biological context. In this review, we summarize proteomics approaches for characterizing matrisome molecules, with an emphasis on applications to brain diseases. We demonstrate the availability of methods that should greatly increase the availability of information on matrisome molecular structure associated with health and disease.


Assuntos
Biomarcadores/análise , Proteínas da Matriz Extracelular/metabolismo , Matriz Extracelular/metabolismo , Glicômica/métodos , Glicoproteínas/metabolismo , Proteoma/análise , Proteômica/métodos , Animais , Glicosilação , Humanos , Processamento de Proteína Pós-Traducional
20.
Toxicol Mech Methods ; 31(4): 288-292, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33297803

RESUMO

Highly toxic industrial chemicals that are widely accessible, and hazardous chemicals like phosgene oxime (CX) that can be easily synthesized, pose a serious threat as potential chemical weapons. In addition, their accidental release can lead to chemical emergencies and mass casualties. CX, an urticant, or nettle agent, grouped with vesicating agents, causes instant pain, injury and systemic effects, which can lead to mortality. With faster cutaneous penetration, corrosive properties, and more potent toxicity compared to other vesicating agents, CX causes instantaneous and severe tissue damage. CX, a potential chemical terrorism threat agent, could therefore be weaponized with other chemical warfare agents to enhance their harmful effects. CX is the least studied vesicant and its acute and long-term toxic effects as well as its mechanism of action are largely unknown. This has hampered the identification of therapeutic targets and the development of effective medical countermeasures. There are only protective measures, decontamination, and supportive treatments available for reducing the toxic effects from CX exposure. This review summarizes CX toxicity, its known mechanism of action, and our current studies exploring the role of mast cell activation and associated signaling pathways in CX cutaneous exposure under the National Institutes of Health Countermeasures Against Chemical Threats program. Potential treatment options and the development of effective targeted countermeasures against CX-induced morbidity and mortality is also discussed.


Assuntos
Oximas/toxicidade , Fosgênio/toxicidade , Substâncias para a Guerra Química/toxicidade , Irritantes , Pele/efeitos dos fármacos
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