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1.
Nano Lett ; 21(21): 9069-9076, 2021 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-34714087

RESUMO

One of the significant challenges to translation of intravenously administered nanomaterials has been complement-mediated infusion reactions which can be lethal. Slow infusions can reduce infusion reactions, but slow infusions are not always possible in applications like controlling bleeding following trauma. Thus, avoiding complement activation and infusion responses is essential to manage bleeding. We identified nanocapsules based on polyurethane as candidates that did not activate C5a and explored their PEGylation and functionalization with the GRGDS peptide to create a new class of hemostatic nanomaterials. Using the clinically relevant rotational thromboelastography (ROTEM), we determined that nanocapsules promote faster clotting than controls and maintain the maximum clot firmness, which is critical for reducing bleeding. Excitingly, these polyurethane-based nanocapsules did not activate complement or the major pro-inflammatory cytokines. This work provides critical evidence for the role of modulating the core material in developing safer nanomedicines for intravenous applications.


Assuntos
Hemostáticos , Nanocápsulas , Hemorragia/tratamento farmacológico , Hemostasia , Hemostáticos/uso terapêutico , Humanos , Tromboelastografia
2.
Prostate ; 79(7): 732-745, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30900284

RESUMO

BACKGROUND: Elevated expression of the proinflammatory cytokine interleukin 1ß (IL-1ß) has been observed in expressed prostatic secretions of patients with chronic prostatitis/chronic pelvic pain syndrome, and genetic polymorphisms associated with the IL1B gene are linked to increased risk for aggressive prostate cancer. METHODS: To study the role of IL-1ß expression in prostate inflammation, we examined IL1B expression in human prostatic proliferative inflammatory atrophy (PIA) lesions and developed a tetracycline-regulated human IL1B transgene in the mouse prostate. RESULTS: Here, we demonstrate that IL1B expression is a common finding in human PIA lesions, which harbored focal IL1B expression in epithelial and stromal compartments. Human IL1B expression in the mouse prostate elicited acute and chronic inflammation. Penetrance and expressivity were variable and tunable by altering transgene dosage and the presence of an exogenous inducible marker antigen (green fluorescent protein). Inflammation was characterized by infiltration of CD4+ T cells, demonstrating an adaptive immune response. Chronic inflammation persisted after doxycycline (Dox) withdrawal. Reactive epithelia increased expression of downstream cytokines, and altered glandular architecture was observed upon sustained induction of IL1B. Immunohistochemical analyses revealed a higher proliferative index and decreased Nkx3.1 expression in inflamed mouse prostates. CONCLUSIONS: These data implicate IL-1ß in human prostate pathology and this model provides a versatile platform to interrogate molecular mechanisms of inflammation-associated prostate pathologies associated with episodic or sustained IL-1ß expression.


Assuntos
Atrofia/imunologia , Linfócitos T CD4-Positivos/imunologia , Inflamação/imunologia , Interleucina-1beta/biossíntese , Próstata/imunologia , Doenças Prostáticas/imunologia , Animais , Doença Crônica , Modelos Animais de Doenças , Humanos , Interleucina-1beta/genética , Masculino , Camundongos , Neoplasias da Próstata/genética , Neoplasias da Próstata/imunologia , Prostatite/imunologia
3.
J Pathol ; 244(1): 11-24, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28888037

RESUMO

Telomerase consists of at least two essential elements, an RNA component hTR or TERC that contains the template for telomere DNA addition and a catalytic reverse transcriptase (TERT). While expression of TERT has been considered the key rate-limiting component for telomerase activity, increasing evidence suggests an important role for the regulation of TERC in telomere maintenance and perhaps other functions in human cancer. By using three orthogonal methods including RNAseq, RT-qPCR, and an analytically validated chromogenic RNA in situ hybridization assay, we report consistent overexpression of TERC in prostate cancer. This overexpression occurs at the precursor stage (e.g. high-grade prostatic intraepithelial neoplasia or PIN) and persists throughout all stages of disease progression. Levels of TERC correlate with levels of MYC (a known driver of prostate cancer) in clinical samples and we also show the following: forced reductions of MYC result in decreased TERC levels in eight cancer cell lines (prostate, lung, breast, and colorectal); forced overexpression of MYC in PCa cell lines, and in the mouse prostate, results in increased TERC levels; human TERC promoter activity is decreased after MYC silencing; and MYC occupies the TERC locus as assessed by chromatin immunoprecipitation (ChIP). Finally, we show that knockdown of TERC by siRNA results in reduced proliferation of prostate cancer cell lines. These studies indicate that TERC is consistently overexpressed in all stages of prostatic adenocarcinoma and that its expression is regulated by MYC. These findings nominate TERC as a novel prostate cancer biomarker and therapeutic target. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasia Prostática Intraepitelial/genética , Neoplasias da Próstata/genética , Proteínas Proto-Oncogênicas c-myc/genética , RNA Interferente Pequeno/genética , RNA/genética , Telomerase/genética , Adulto , Idoso , Animais , Proliferação de Células , Genes Reporter , Humanos , Hibridização In Situ , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Próstata/patologia , Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/patologia , Análise de Sequência de RNA , Telômero/genética
4.
Blood Adv ; 8(15): 3880-3892, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739710

RESUMO

ABSTRACT: Provirus integration site for Moloney murine leukemia virus (PIM) family serine/threonine kinases perform protumorigenic functions in hematologic malignancies and solid tumors by phosphorylating substrates involved in tumor metabolism, cell survival, metastasis, inflammation, and immune cell invasion. However, a comprehensive understanding of PIM kinase functions is currently lacking. Multiple small-molecule PIM kinase inhibitors are currently being evaluated as cotherapeutics in patients with cancer. To further illuminate PIM kinase functions in cancer, we deeply profiled PIM1 substrates using the reverse in-gel kinase assay to identify downstream cellular processes targetable with small molecules. Pathway analyses of putative PIM substrates nominated RNA splicing and ribosomal RNA (rRNA) processing as PIM-regulated cellular processes. PIM inhibition elicited reproducible splicing changes in PIM-inhibitor-responsive acute myeloid leukemia (AML) cell lines. PIM inhibitors synergized with splicing modulators targeting splicing factor 3b subunit 1 (SF3B1) and serine-arginine protein kinase 1 (SRPK1) to kill AML cells. PIM inhibition also altered rRNA processing, and PIM inhibitors synergized with an RNA polymerase I inhibitor to kill AML cells and block AML tumor growth. These data demonstrate that deep kinase substrate knowledge can illuminate unappreciated kinase functions, nominating synergistic cotherapeutic strategies. This approach may expand the cotherapeutic armamentarium to overcome kinase inhibitor-resistant disease that limits durable responses in malignant disease.


Assuntos
Leucemia Mieloide Aguda , Inibidores de Proteínas Quinases , Proteínas Proto-Oncogênicas c-pim-1 , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Humanos , Proteínas Proto-Oncogênicas c-pim-1/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-pim-1/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Camundongos , Animais , Linhagem Celular Tumoral , Especificidade por Substrato , Splicing de RNA/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Neurology ; 101(8): 357-368, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-36997322

RESUMO

BACKGROUND AND OBJECTIVES: Use a modified Delphi approach to develop competencies for neurologists completing ≥1 year of advanced global neurology training. METHODS: An expert panel of 19 United States-based neurologists involved in global health was recruited from the American Academy of Neurology Global Health Section and the American Neurological Association International Outreach Committee. An extensive list of global health competencies was generated from review of global health curricula and adapted for global neurology training. Using a modified Delphi method, United States-based neurologists participated in 3 rounds of voting on a survey with potential competencies rated on a 4-point Likert scale. A final group discussion was held to reach consensus. Proposed competencies were then subjected to a formal review from a group of 7 neurologists from low- and middle-income countries (LMICs) with experience working with neurology trainees from high-income countries (HICs) who commented on potential gaps, feasibility, and local implementation challenges of the proposed competencies. This feedback was used to modify and finalize competencies. RESULTS: Three rounds of surveys, a conference call with United States-based experts, and a semistructured questionnaire and focus group discussion with LMIC experts were used to discuss and reach consensus on the final competencies. This resulted in a competency framework consisting of 47 competencies across 8 domains: (1) cultural context, social determinants of health and access to care; (2) clinical and teaching skills and neurologic medical knowledge; (3) team-based practice; (4) developing global neurology partnerships; (5) ethics; (6) approach to clinical care; (7) community neurologic health; (8) health care systems and multinational health care organizations. DISCUSSION: These proposed competencies can serve as a foundation on which future global neurology training programs can be built and trainees evaluated. It may also serve as a model for global health training programs in other medical specialties as well as a framework to expand the number of neurologists from HICs trained in global neurology.


Assuntos
Bolsas de Estudo , Neurologia , Humanos , Estados Unidos , Consenso , Currículo , Neurologia/educação , Competência Clínica , Saúde Pública , Técnica Delphi
6.
Mult Scler Relat Disord ; 29: 1-6, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30654245

RESUMO

The differential diagnosis for transverse myelitis is extensive, and the prognosis is highly variable depending on the etiology. We describe a rare case of a 56-year-old previously healthy male who presented with thoracic paresthesias and hyperesthesias involving the T6-11 dermatomes several weeks after a febrile illness. A thoracic MRI demonstrated a T7-10 transverse myelitis, and an exhaustive evaluation revealed neuroborreliosis. His symptoms improved significantly after an initial steroid course and 21 day course of ceftriaxone. We review neuroborreliosis and summarize the features of 23 previously reported cases of Lyme myelopathy. Although Lyme myelopathy is rare, including Lyme in the differential diagnosis of an acute transverse myelitis work up is important in endemic regions, as it is a potentially reversible disorder with a generally good prognosis when appropriately treated with antibiotics.


Assuntos
Neuroborreliose de Lyme/diagnóstico , Mielite Transversa/diagnóstico , Antibacterianos/farmacologia , Humanos , Neuroborreliose de Lyme/complicações , Neuroborreliose de Lyme/tratamento farmacológico , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mielite Transversa/tratamento farmacológico , Mielite Transversa/etiologia , Vértebras Torácicas
7.
Mol Cancer Res ; 17(12): 2480-2491, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31611308

RESUMO

A key hallmark of cancer, unlimited replication, requires cancer cells to evade both replicative senescence and potentially lethal chromosomal instability induced by telomere dysfunction. The majority of cancers overcome these critical barriers by upregulating telomerase, a telomere-specific reverse transcriptase. However, a subset of cancers maintains telomere lengths by the telomerase-independent Alternative Lengthening of Telomeres (ALT) pathway. The presence of ALT is strongly associated with recurrent cancer-specific somatic inactivating mutations in the ATRX-DAXX chromatin-remodeling complex. Here, we generate an ALT-positive adenocarcinoma cell line following functional inactivation of ATRX and telomerase in a telomerase-positive adenocarcinoma cell line. Inactivating mutations in ATRX were introduced using CRISPR-cas9 nickase into two prostate cancer cell lines, LAPC-4 (derived from a lymph node metastasis) and CWR22Rv1 (sourced from a xenograft established from a primary prostate cancer). In LAPC-4, but not CWR22Rv1, abolishing ATRX was sufficient to induce multiple ALT-associated hallmarks, including the presence of ALT-associated promyelocytic leukemia bodies (APB), extrachromosomal telomere C-circles, and dramatic telomere length heterogeneity. However, telomerase activity was still present in these ATRXKO cells. Telomerase activity was subsequently crippled in these LAPC-4 ATRXKO cells by introducing mutations in the TERC locus, the essential RNA component of telomerase. These LAPC-4 ATRXKO TERCmut cells continued to proliferate long-term and retained ALT-associated hallmarks, thereby demonstrating their reliance on the ALT mechanism for telomere maintenance. IMPLICATIONS: These prostate cancer cell line models provide a unique system to explore the distinct molecular alterations that occur upon induction of ALT, and may be useful tools to screen for ALT-specific therapies.


Assuntos
Neoplasias da Próstata/genética , RNA/genética , Telomerase/genética , Homeostase do Telômero/genética , Proteína Nuclear Ligada ao X/genética , Sistemas CRISPR-Cas/genética , Linhagem Celular Tumoral , Montagem e Desmontagem da Cromatina/genética , Instabilidade Cromossômica/genética , Regulação Neoplásica da Expressão Gênica/genética , Técnicas de Inativação de Genes , Humanos , Masculino , Mutação , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/patologia , Telômero/genética
8.
J Clin Neurosci ; 43: 132-134, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28526178

RESUMO

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease resulting from infection of oligodendrocytes in the central nervous system with John Cunningham virus. Although PML is commonly diagnosed in immunocompromised patients with human immunodeficiency virus, it can also arise in other immunodeficient states. In this report, we present an unusual case of PML occurring 40years after chemoradiation therapy for Hodgkin lymphoma in a patient with normal total lymphocyte counts on annual surveillance. Although current guidelines recommend annual complete blood counts for patients in remission, this testing may be insufficient to monitor patients with chronic CD4+ lymphopenia.


Assuntos
Leucoencefalopatia Multifocal Progressiva/complicações , Idoso , Doença de Hodgkin/complicações , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/radioterapia , Humanos , Transtornos de Início Tardio/complicações , Masculino
9.
Science ; 345(6198): 795-9, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25124435

RESUMO

Self-assembly enables nature to build complex forms, from multicellular organisms to complex animal structures such as flocks of birds, through the interaction of vast numbers of limited and unreliable individuals. Creating this ability in engineered systems poses challenges in the design of both algorithms and physical systems that can operate at such scales. We report a system that demonstrates programmable self-assembly of complex two-dimensional shapes with a thousand-robot swarm. This was enabled by creating autonomous robots designed to operate in large groups and to cooperate through local interactions and by developing a collective algorithm for shape formation that is highly robust to the variability and error characteristic of large-scale decentralized systems. This work advances the aim of creating artificial swarms with the capabilities of natural ones.

12.
Int J Dev Biol ; 53(5-6): 869-81, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19557691

RESUMO

This paper presents a novel perspective of Robotic Stem Cells (RSCs), defined as the basic non-biological elements with stem cell like properties that can self-reorganize to repair damage to their swarming organization. Self here means that the elements can autonomously decide and execute their actions without requiring any preset triggers, commands, or help from external sources. We develop this concept for two purposes. One is to develop a new theory for self-organization and self-assembly of multi-robots systems that can detect and recover from unforeseen errors or attacks. This self-healing and self-regeneration is used to minimize the compromise of overall function for the robot team. The other is to decipher the basic algorithms of regenerative behaviors in multi-cellular animal models, so that we can understand the fundamental principles used in the regeneration of biological systems. RSCs are envisioned to be basic building elements for future systems that are capable of self-organization, self-assembly, self-healing and self-regeneration. We first discuss the essential features of biological stem cells for such a purpose, and then propose the functional requirements of robotic stem cells with properties equivalent to gene controller, program selector and executor. We show that RSCs are a novel robotic model for scalable self-organization and self-healing in computer simulations and physical implementation. As our understanding of stem cells advances, we expect that future robots will be more versatile, resilient and complex, and such new robotic systems may also demand and inspire new knowledge from stem cell biology and related fields, such as artificial intelligence and tissue engineering.


Assuntos
Biologia do Desenvolvimento/métodos , Células-Tronco Hematopoéticas/citologia , Algoritmos , Animais , Inteligência Artificial , Diferenciação Celular , Proliferação de Células , Simulação por Computador , Humanos , Modelos Biológicos , Linguagens de Programação , Regeneração , Robótica , Software , Engenharia Tecidual/métodos
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