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1.
Gan To Kagaku Ryoho ; 51(3): 291-297, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38494811

RESUMO

An 84-year-old woman was diagnosed as having acute promyelocytic leukemia(APL)in July Year X-3. The test for promyelocytic leukemia- retinoic acid receptor alpha(PML-RARA)mRNA was positive, while that for CD56 was negative. Since her white blood cell( WBC) count was <3,000/µL, with a count of APL cells of <1,000/µL, she was started on monotherapy with all-trans retinoic acid(ATRA). In September Year X-3, complete hematological remission(CHR)was confirmed. she refused to provide consent for receiving consolidation therapy. In February Year X-2, hematological relapse occurred. She was started on re-induction therapy with arsenite(ATO), and in June Year X-2, complete molecular remission(CMR)was achieved. She was started on post-remission therapy with ATO. In August Year X-1, she developed molecular relapse and was started on tamibarotene(Am80). In October Year X-1, hematological relapse was detected, and the test for CD56 was positive. She was started on combined venetoclax(VEN)+azacitidine(AZA)(VEN+AZA). After completion of 1 course of treatment, CMR was achieved, but she developed hematological relapse after 5 courses of treatment. She died of gastrointestinal hemorrhage. This is considered a valuable case for accumulating information on the treatment of CD56-positive APL resistant to ATRA and ATO.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes , Leucemia Promielocítica Aguda , Sulfonamidas , Humanos , Feminino , Idoso de 80 Anos ou mais , Leucemia Promielocítica Aguda/tratamento farmacológico , Trióxido de Arsênio/uso terapêutico , Azacitidina/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Tretinoína/uso terapêutico , Recidiva
2.
Case Rep Hematol ; 2023: 8568587, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38124780

RESUMO

We report a case of FLT3-mutated APL who developed disease relapse despite all-trans retinoic acid (ATRA) + chemotherapy, and re-induction chemotherapy with arsenic trioxide (ATO) and high-dose (HD) cytarabine (Ara-C) therapy failed to yield complete remission. Because the leukemic cells were resistant to all the aforementioned therapies, we started the patient on monotherapy with gilteritinib, a selective FLT3-inhibitor, as an alternative re-induction treatment option rather than further intensive chemotherapy. The patient showed complete hematologic remission in response to this therapy. This case serves as supporting evidence for the use of single-agent therapy with gilteritinib as a bridge to transplantation in patients with refractory FLT3-mutated APL.

4.
Gan To Kagaku Ryoho ; 50(9): 985-992, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37800294

RESUMO

An 84-year-old female developed gross hematuria. She was diagnosed as urinary bladder carcinoma. She was initiated on concurrent atezolizumab plus radiation(a phase Ⅱ clinical trial)(jRCT2031180060). After 8 cycles of atezolizumab, complete response was confirmed. Maintenance atezolizumab treatment was started. Platelet(Plt)count decreased, there was no rechallenge with atezolizumab. Bone marrow examination revealed normal. Plt count recovered. Plt count decreased again. The serum levels of interleukin-6(IL-6)were elevated. She was diagnosed as having immune thrombocytopenia. She was started on treatment with prednisolone(PSL)at dose of 20 mg/day. Plt count was increased.


Assuntos
Púrpura Trombocitopênica Idiopática , Trombocitopenia , Neoplasias da Bexiga Urinária , Feminino , Humanos , Idoso de 80 Anos ou mais , Trombocitopenia/induzido quimicamente , Anticorpos Monoclonais Humanizados/uso terapêutico , Neoplasias da Bexiga Urinária/terapia
6.
Gan To Kagaku Ryoho ; 49(11): 1233-1239, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36412027

RESUMO

A 76-year-old woman with a past history of diabetes mellitus and Hashimoto's disease, in regard to her personal history, she did not smoke or drink alcohol. In March, year X-1, she became aware of cervical lymphadenopathy. Based on the findings of lymph node biopsy, she was diagnosed as having diffuse large B-cell lymphoma(DLBCL). An upper gastrointestinal endoscopy(U-GIE)revealed white granular prominences in the gastric fornix, and biopsy of these lesions revealed the diagnosis of Russell body gastritis(RBG). Neither lymphoma infiltration nor other malignant findings were found. Diagnostic tests for Helicobacter pylori were negative. The clinical stage of the DLBCL was determined as stage ⅢA, and the International Prognostic Index was"high intermediate". She received 6 cycles of R-CHOP therapy, with concomitant use of a proton pump inhibitor. Complete remission was confirmed in November, year X-1. An U-GIE performed again no longer showed the white granular prominences in the gastric fornix. The present report is the first of DLBCL complicated by RBG; our findings suggested that the two diseases were associated with each other.


Assuntos
Gastrite , Infecções por Helicobacter , Helicobacter pylori , Linfoma Difuso de Grandes Células B , Humanos , Feminino , Idoso , Gastrite/complicações , Gastrite/tratamento farmacológico , Infecções por Helicobacter/complicações , Infecções por Helicobacter/tratamento farmacológico , Linfoma Difuso de Grandes Células B/complicações , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Rituximab
7.
mBio ; 13(6): e0230822, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36314791

RESUMO

Coronavirus disease 2019 (COVID-19) is frequently associated with neurological deficits, but how severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces these effects remains unclear. Here, we show that astrocytes are readily infected by SARS-CoV-2, but surprisingly, neuropilin-1, not angiotensin-converting enzyme 2 (ACE2), serves as the principal receptor mediating cell entry. Infection is further positively modulated by the two-pore segment channel 2 (TPC2) protein that regulates membrane trafficking and endocytosis. Astrocyte infection produces a pathological response closely resembling reactive astrogliosis characterized by elevated type I interferon (IFN) production, increased inflammation, and the decreased expression of transporters of water, ions, choline, and neurotransmitters. These combined events initiated within astrocytes produce a hostile microenvironment that promotes the dysfunction and death of uninfected bystander neurons. IMPORTANCE SARS-CoV-2 infection primarily targets the lung but may also damage other organs, including the brain, heart, kidney, and intestine. Central nervous system (CNS) pathologies include loss of smell and taste, headache, delirium, acute psychosis, seizures, and stroke. Pathological loss of gray matter occurs in SARS-CoV-2 infection, but it is unclear whether this is due to direct viral infection, indirect effects associated with systemic inflammation, or both. Here, we used induced pluripotent stem cell (iPSC)-derived brain organoids and primary human astrocytes from the cerebral cortex to study direct SARS-CoV-2 infection. Our findings support a model where SARS-CoV-2 infection of astrocytes produces a panoply of changes in the expression of genes regulating innate immune signaling and inflammatory responses. The deregulation of these genes in astrocytes produces a microenvironment within the CNS that ultimately disrupts normal neuron function, promoting neuronal cell death and CNS deficits.


Assuntos
COVID-19 , Humanos , SARS-CoV-2/fisiologia , Astrócitos , Neuropilina-1 , Encéfalo , Inflamação , Neurônios , Organoides
8.
Nat Methods ; 19(8): 995-1003, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35879608

RESUMO

Explaining the diversity and complexity of protein localization is essential to fully understand cellular architecture. Here we present cytoself, a deep-learning approach for fully self-supervised protein localization profiling and clustering. Cytoself leverages a self-supervised training scheme that does not require preexisting knowledge, categories or annotations. Training cytoself on images of 1,311 endogenously labeled proteins from the OpenCell database reveals a highly resolved protein localization atlas that recapitulates major scales of cellular organization, from coarse classes, such as nuclear and cytoplasmic, to the subtle localization signatures of individual protein complexes. We quantitatively validate cytoself's ability to cluster proteins into organelles and protein complexes, showing that cytoself outperforms previous self-supervised approaches. Moreover, to better understand the inner workings of our model, we dissect the emergent features from which our clustering is derived, interpret them in the context of the fluorescence images, and analyze the performance contributions of each component of our approach.


Assuntos
Aprendizado Profundo , Análise por Conglomerados , Organelas/metabolismo , Transporte Proteico , Proteínas/metabolismo
9.
Nat Methods ; 19(4): 461-469, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35314838

RESUMO

The promise of single-objective light-sheet microscopy is to combine the convenience of standard single-objective microscopes with the speed, coverage, resolution and gentleness of light-sheet microscopes. We present DaXi, a single-objective light-sheet microscope design based on oblique plane illumination that achieves: (1) a wider field of view and high-resolution imaging via a custom remote focusing objective; (2) fast volumetric imaging over larger volumes without compromising image quality or necessitating tiled acquisition; (3) fuller image coverage for large samples via multi-view imaging and (4) higher throughput multi-well imaging via remote coverslip placement. Our instrument achieves a resolution of 450 nm laterally and 2 µm axially over an imaging volume of 3,000 × 800 × 300 µm. We demonstrate the speed, field of view, resolution and versatility of our instrument by imaging various systems, including Drosophila egg chamber development, zebrafish whole-brain activity and zebrafish embryonic development - up to nine embryos at a time.


Assuntos
Encéfalo , Peixe-Zebra , Animais , Encéfalo/diagnóstico por imagem , Drosophila , Desenvolvimento Embrionário , Microscopia de Fluorescência/métodos
10.
Science ; 375(6585): eabi6983, 2022 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-35271311

RESUMO

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


Assuntos
Mapeamento de Interação de Proteínas , Proteínas/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Sistemas CRISPR-Cas , Análise por Conglomerados , Conjuntos de Dados como Assunto , Corantes Fluorescentes , Células HEK293 , Humanos , Imunoprecipitação , Aprendizado de Máquina , Espectrometria de Massas , Microscopia Confocal , Proteínas de Ligação a RNA/metabolismo , Análise Espacial
11.
Intern Med ; 61(16): 2503-2508, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35110483

RESUMO

A 74-year-old woman was diagnosed with Waldenstrom macroglobulinemia/lymphoplasmacytic lymphoma (WM/LPL) in X-18. Fludarabine plus rituximab (FR) was started, and she showed remission. In July X-7, the serum creatinine (Cr) level increased to 1.67 mg/dL, and bendamustine plus rituximab (BR) was started. By November X-7, the Cr level had increased to 8.41 mg/dL, so she was started on hemodialysis (HD). In September X-1, she developed nephrotic syndrome. She was started on tirabrutinib at 480 mg. In July X, her nephrotic syndrome had improved, and a complete response (CR) was achieved. This is the first case of the administration of tirabrutinib in a patient undergoing HD.


Assuntos
Linfoma , Síndrome Nefrótica , Macroglobulinemia de Waldenstrom , Idoso , Feminino , Humanos , Imidazóis , Linfoma/complicações , Síndrome Nefrótica/complicações , Síndrome Nefrótica/tratamento farmacológico , Pirimidinas , Diálise Renal , Rituximab/uso terapêutico , Macroglobulinemia de Waldenstrom/complicações , Macroglobulinemia de Waldenstrom/diagnóstico , Macroglobulinemia de Waldenstrom/tratamento farmacológico
12.
Elife ; 102021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34882088

RESUMO

In the past few decades, aquatic animals have become popular model organisms in biology, spurring a growing need for establishing aquatic facilities. Zebrafish are widely studied and relatively easy to culture using commercial systems. However, a challenging aspect of maintaining aquatic facilities is animal feeding, which is both time- and resource-consuming. We have developed an open-source fully automatic daily feeding system, Zebrafish Automatic Feeder (ZAF). ZAF is reliable, provides a standardized amount of food to every tank, is cost-efficient and easy to build. The advanced version, ZAF+, allows for the precise control of food distribution as a function of fish density per tank, and has a user-friendly interface. Both ZAF and ZAF+ are adaptable to any laboratory environment and facilitate the implementation of aquatic colonies. Here, we provide all blueprints and instructions for building the mechanics, electronics, fluidics, as well as to setup the control software and its user-friendly graphical interface. Importantly, the design is modular and can be scaled to meet different user needs. Furthermore, our results show that ZAF and ZAF+ do not adversely affect zebrafish culture, enabling fully automatic feeding for any aquatic facility.


Assuntos
Aquicultura/instrumentação , Automação/instrumentação , Software , Peixe-Zebra/fisiologia , Ração Animal , Animais , Aquicultura/métodos , Automação/métodos , Coleta de Dados , Comportamento Alimentar
13.
Sci Rep ; 11(1): 18480, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34531519

RESUMO

Underwater walking is one of the most common hydrotherapeutic exercises. Therefore, understanding muscular control during underwater walking is important for optimizing training regimens. The effects of the water environment on walking are mainly related to the hydrostatic and hydrodynamic theories of buoyancy and drag force. To date, muscular control during underwater walking has been investigated at the individual muscle level. However, it is recognized that the human nervous system modularly controls multiple muscles through muscle synergies, which are sets of muscles that work together. We found that the same set of muscle synergies was shared between the two walking tasks. However, some task-dependent modulation was found in the activation combination across muscles and temporal activation patterns of the muscle synergies. The results suggest that the human nervous system modulates activation of lower-limb muscles during water walking by finely tuning basic locomotor muscle synergies that are used during land walking to meet the biomechanical requirements for walking in the water environment.


Assuntos
Músculo Esquelético/fisiologia , Caminhada/fisiologia , Adulto , Fenômenos Biomecânicos , Geradores de Padrão Central/fisiologia , Humanos , Imersão , Masculino , Músculo Esquelético/inervação , Água
14.
Sci Rep ; 11(1): 8211, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33859271

RESUMO

How do skilled players change their motion patterns depending on motion effort? Pitchers commonly accelerate wrist and elbow joint rotations via proximal joint motions. Contrastingly, they show individually different pitching motions, such as in wind-up or follow-through. Despite the generality of the uniform and diverse features, effort-dependent effects on these features are unclear. Here, we reveal the effort dependence based on muscle activity data in natural three-dimensional pitching performed by skilled players. We extract motor modules and their effort dependence from the muscle activity data via tensor decomposition. Then, we reveal the unknown relations among motor modules, common features, unique features, and effort dependence. The current study clarifies that common features are obvious in distinguishing between low and high effort and that unique features are evident in differentiating high and highest efforts.


Assuntos
Beisebol/fisiologia , Atividade Motora/fisiologia , Fenômenos Fisiológicos Musculoesqueléticos , Esforço Físico/fisiologia , Aceleração , Adulto , Atletas , Fenômenos Biomecânicos/fisiologia , Articulação do Cotovelo/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular/fisiologia , Articulação do Ombro/fisiologia , Articulação do Punho/fisiologia , Adulto Jovem
15.
Neurorehabil Neural Repair ; 35(3): 220-232, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33514276

RESUMO

BACKGROUND: We recently discovered that individuals with complete spinal cord injury (SCI) have a higher grip force control ability in their intact upper limbs than able-bodied subjects. However, the neural basis for this phenomenon is unknown. OBJECTIVE: This study aimed to investigate the neural basis of the higher grip force control in the brains of individuals with SCI using multimodal magnetic resonance imaging (MRI). METHODS: Eight SCI subjects and 10 able-bodied subjects performed hand grip force control tasks at 10%, 20%, and 30% of their maximal voluntary contraction during functional MRI (fMRI). Resting-state fMRI and T1-weighted structural images were obtained to investigate changes in brain networks and structures after SCI. RESULTS: SCI subjects showed higher grip force steadiness than able-bodied subjects (P < .05, corrected), smaller activation in the primary motor cortex (P < .05, corrected), and deactivation of the visual cortex (P < .001, uncorrected). Furthermore, SCI subjects had stronger functional connectivity between the superior parietal lobule and the left primary motor cortex (P < .001, uncorrected), as well as larger gray matter volume in the bilateral superior parietal lobule (P < .001, uncorrected). CONCLUSIONS: The structural and functional reorganization observed in the superior parietal lobule of SCI subjects may represent the neural basis underlying the observed higher grip force control, and is likely responsible for the smaller activation in the primary motor cortex observed in these individuals. These findings could have applications in the fields of neurorehabilitation for improvement of intact limb functions after SCI.


Assuntos
Mapeamento Encefálico , Substância Cinzenta , Força da Mão/fisiologia , Imageamento por Ressonância Magnética , Córtex Motor , Plasticidade Neuronal/fisiologia , Lobo Parietal , Traumatismos da Medula Espinal/diagnóstico por imagem , Adulto , Idoso , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Substância Cinzenta/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/diagnóstico por imagem , Córtex Motor/patologia , Córtex Motor/fisiopatologia , Contração Muscular/fisiologia , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/patologia , Lobo Parietal/fisiopatologia , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologia , Adulto Jovem
16.
Artigo em Inglês | MEDLINE | ID: mdl-33345028

RESUMO

This study explored the mechanical factors that determine accuracy of a baseball pitching. In particular, we focused on the mechanical parameters at ball release, referred to as release parameters. The aim was to understand which parameter has the most deterministic influence on pitch location by measuring the release parameters during actual pitching and developing a simulation that predicts the pitch location from given release parameters. By comparing the fluctuation of the simulated pitch location when varying each release parameter, it was found that the elevation pitching angle and speed significantly influenced the vertical pitch location, and the azimuth pitching angle significantly influenced the horizontal pitch location. Moreover, a regression model was obtained to predict the pitch location, and it became clear that the significant predictors for the vertical pitch location were the elevation pitching angle, the speed, and spin axis, and those for the horizontal pitch location were the azimuth pitching angle, the spin axis, and horizontal release point. Therefore, it was suggested that the parameter most affecting pitch location weas pitching angle. On the other hand, multiple regression analyses revealed that the relation between release parameters varied between pitchers. The result is expected to contribute to an understanding of the mechanisms underlying accurate ball control skill in baseball pitching.

17.
Sports Biomech ; : 1-14, 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33118477

RESUMO

The present study was a cross-sectional comparison of probabilistic structure in the distribution of pitching location among baseball pitchers of various age groups (25 elementary school (ES), 20 junior high school (JH), 15 high school (HS), and 18 college students (CL)). In the results, despite the general age-dependent variations in pitching precision, the difference was reflected not only in error 'size' but also in the 'shape' of error as it was shown by fitting 95% confidence ellipse to the two dimensional distribution of pitch location. While the precision measure as a reflection of trial-by-trial variability of release timing (major axis length of the ellipse) was constant, minor axis length of the ellipse as a reflection of variability in the pitching form of each participant demonstrated significant differences among the groups. In the ES group particularly, the trial-by-trial variability in the trajectory angle of the throwing arm was significantly correlated with the minor axis length; this correlation was far greater than those in older groups. The present study is the first to demonstrate the detailed structure of the variability of pitching location of baseball dependent on age.

18.
Cancer Sci ; 111(10): 3770-3779, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32767806

RESUMO

The efficiency of upfront consolidation with high-dose chemotherapy/autologous stem-cell transplantation (HDCT/ASCT) for newly diagnosed high-risk diffuse large B-cell lymphoma (DLBCL) may be influenced by induction chemotherapy. To select better induction chemotherapy regimens for HDCT/ASCT, a randomized phase II study was conducted in high-risk DLBCL patients having an age-adjusted International Prognostic Index (aaIPI) score of 2 or 3. As induction chemotherapy, 6 cycles of R-CHOP-14 (arm A) or 3 cycles of R-CHOP-14 followed by 3 cycles of CHASER (arm B) were planned, and patients who responded proceeded to HDCT with LEED and ASCT. The primary endpoint was 2-y progression-free survival (PFS), and the main secondary endpoints included overall survival, overall response rate, and adverse events (AEs). In total, 71 patients were enrolled. With a median follow-up of 40.3 mo, 2-y PFS in arms A and B were 68.6% (95% confidence interval [CI], 50.5%-81.2%) and 66.7% (95% CI: 48.8%-79.5%), respectively. Overall survival at 2 y in arms A and B was 74.3% (95% CI: 56.4%-85.7%) and 83.3% (95% CI: 66.6%-92.1%). Overall response rates were 82.9% in arm A and 69.4% in arm B. During induction chemotherapy, 45.7% and 75.0% of patients in arms A and B, respectively, had grade ≥ 3 non-hematologic toxicities. One patient in arm A and 6 in arm B discontinued induction chemotherapy due to AEs. In conclusion, R-CHOP-14 showed higher 2-y PFS and less toxicity compared with R-CHOP-14/CHASER in patients with high-risk DLBCL, suggesting the former to be a more promising induction regimen for further investigations (UMIN-CTR, UMIN000003823).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Transplante de Células-Tronco Hematopoéticas/métodos , Quimioterapia de Indução/métodos , Linfoma Difuso de Grandes Células B/terapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Terapia Combinada , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Intervalo Livre de Progressão , Rituximab/administração & dosagem , Rituximab/efeitos adversos , Transplante Autólogo/efeitos adversos , Vincristina/administração & dosagem , Vincristina/efeitos adversos , Adulto Jovem
19.
Nat Commun ; 11(1): 3452, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-32651381

RESUMO

The advent of image-activated cell sorting and imaging-based cell picking has advanced our knowledge and exploitation of biological systems in the last decade. Unfortunately, they generally rely on fluorescent labeling for cellular phenotyping, an indirect measure of the molecular landscape in the cell, which has critical limitations. Here we demonstrate Raman image-activated cell sorting by directly probing chemically specific intracellular molecular vibrations via ultrafast multicolor stimulated Raman scattering (SRS) microscopy for cellular phenotyping. Specifically, the technology enables real-time SRS-image-based sorting of single live cells with a throughput of up to ~100 events per second without the need for fluorescent labeling. To show the broad utility of the technology, we show its applicability to diverse cell types and sizes. The technology is highly versatile and holds promise for numerous applications that are previously difficult or undesirable with fluorescence-based technologies.


Assuntos
Separação Celular/métodos , Análise Espectral Raman/métodos , Animais , Humanos
20.
Elife ; 92020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32393438

RESUMO

Platelets are anucleate cells in blood whose principal function is to stop bleeding by forming aggregates for hemostatic reactions. In addition to their participation in physiological hemostasis, platelet aggregates are also involved in pathological thrombosis and play an important role in inflammation, atherosclerosis, and cancer metastasis. The aggregation of platelets is elicited by various agonists, but these platelet aggregates have long been considered indistinguishable and impossible to classify. Here we present an intelligent method for classifying them by agonist type. It is based on a convolutional neural network trained by high-throughput imaging flow cytometry of blood cells to identify and differentiate subtle yet appreciable morphological features of platelet aggregates activated by different types of agonists. The method is a powerful tool for studying the underlying mechanism of platelet aggregation and is expected to open a window on an entirely new class of clinical diagnostics, pharmacometrics, and therapeutics.


Platelets are small cells in the blood that primarily help stop bleeding after an injury by sticking together with other blood cells to form a clot that seals the broken blood vessel. Blood clots, however, can sometimes cause harm. For example, if a clot blocks the blood flow to the heart or the brain, it can result in a heart attack or stroke, respectively. Blood clots have also been linked to harmful inflammation and the spread of cancer, and there are now preliminary reports of remarkably high rates of clotting in COVID-19 patients in intensive care units. A variety of chemicals can cause platelets to stick together. It has long been assumed that it would be impossible to tell apart the clots formed by different chemicals (which are also known as agonists). This is largely because these aggregates all look very similar under a microscope, making it incredibly time consuming for someone to look at enough microscopy images to reliably identify the subtle differences between them. However, finding a way to distinguish the different types of platelet aggregates could lead to better ways to diagnose or treat blood vessel-clogging diseases. To make this possible, Zhou, Yasumoto et al. have developed a method called the "intelligent platelet aggregate classifier" or iPAC for short. First, numerous clot-causing chemicals were added to separate samples of platelets taken from healthy human blood. The method then involved using high-throughput techniques to take thousands of images of these samples. Then, a sophisticated computer algorithm called a deep learning model analyzed the resulting image dataset and "learned" to distinguish the chemical causes of the platelet aggregates based on subtle differences in their shapes. Finally, Zhou, Yasumoto et al. verified iPAC method's accuracy using a new set of human platelet samples. The iPAC method may help scientists studying the steps that lead to clot formation. It may also help clinicians distinguish which clot-causing chemical led to a patient's heart attack or stroke. This could help them choose whether aspirin or another anti-platelet drug would be the best treatment. But first more studies are needed to confirm whether this method is a useful tool for drug selection or diagnosis.


Assuntos
Redes Neurais de Computação , Agregação Plaquetária , Citometria de Fluxo , Humanos , Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas , Ativação Plaquetária , Trombose/classificação
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