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1.
J Surg Res ; 293: 468-474, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37820395

RESUMO

INTRODUCTION: The objective of this study was to investigate the potential synergistic utility of a combination of gaseous nitric oxide (gNO)-intravenous Cangrelor as an effective pharmacological option for the prevention of thrombosis in an animal model of extracorporeal life support (ECLS) circuits. METHODS: 10 newborn lambs were placed on ECLS. 5 of them were administered a combination of gNO and intravenous Cangrelor. The remaining 5 were not administered any anticoagulant. The primary end point was duration of ECLS without clot formation. The secondary outcome measure was the absolute maximum transmembrane pressure gradient. RESULTS: The mean duration of ECLS were 168 min (standard deviation 224.98 min) in the control group and 402 min (standard deviation 287.5 min) in the experimental group (P = 0.17). The peak trans-oxygenator pressure difference was 43 mm Hg (standard deviation 23 mm Hg) in the control group and 62 mm Hg (standard deviation 71 mm Hg) in the experimental group(P = 0.64). Two animals in the experimental group were supported up to 12 h without clot formation. Clot formation in the experimental group occurred after placement of the cannulae but prior to initiation of ECLS flows after cannulation. CONCLUSIONS: A combination of gNO and Cangrelor is prevents clot formation in an experimental animal model when administered through a clean clot-free circuit. However, the combination s ineffective when there are pre-existing clots in the circuit. A bolus of anticoagulation prior to cannulation is needed prior to testing this combination in future studies with a larger sample size.


Assuntos
Oxigenação por Membrana Extracorpórea , Trombose , Ovinos , Animais , Óxido Nítrico , Gases , Trombose/etiologia , Trombose/prevenção & controle
2.
J Emerg Med ; 58(4): 603-609, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32245689

RESUMO

BACKGROUND: Acute pain represents one of the most common reasons for emergency department (ED) visits. In the opioid epidemic that North America faces, there is a significant demand for novel effective pain control modalities, especially in the acute setting. OBJECTIVES: The goal of this study was to review all the indications and summarize the efficacy of the Erector Spinae Plane Block (ESPB) in the ED. METHODS: PubMed, EMBASE, and MEDLINE, as well as CINAHL databases were searched according to the PRISMA guidelines to find any study reporting on the use of ESPB in the ED. RESULTS: Ten studies were published reporting on seven different indications for the use of ESPB in the ED. It was most commonly used for rib and spine fractures. Other indications included: mechanical pain, burn injuries, herpes zoster, renal colic, and acute pancreatitis. All the studies demonstrated a significant reduction in pain after administration of ESPB. Furthermore, it has been reported to improve respiratory function and was not associated with any complications after administration. CONCLUSIONS: ESPB is an easy-to-administer interfascial plane block that has several indications and promising potential for acute pain management in the ED. The easily identified landmarks coupled with its low complication rate makes it an appealing technique to be used by emergency physicians in the context of acute pain management. Further studies should investigate any other possible indications and compare its efficacy with other techniques, such as epidurals and serratus anterior blocks.


Assuntos
Bloqueio Nervoso , Pancreatite , Doença Aguda , Analgésicos Opioides/uso terapêutico , Serviço Hospitalar de Emergência , Humanos , Dor
3.
Semin Cancer Biol ; 27: 62-73, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24631834

RESUMO

Nuclear-cytoplasmic trafficking of proteins is a significant factor in the development of cancer and drug resistance. Subcellular localization of exported proteins linked to cancer development include those involved in cell growth and proliferation, apoptosis, cell cycle regulation, transformation, angiogenesis, cell adhesion, invasion, and metastasis. Here, we examined the basic mechanisms involved in the export of proteins from the nucleus to the cytoplasm. All proteins over 40kDa use the nuclear pore complex to gain entry or exit from the nucleus, with the primary nuclear export molecule involved in these processes being chromosome region maintenance 1 (CRM1, exportin 1 or XPO1). Proteins exported from the nucleus must possess a hydrophobic nuclear export signal (NES) peptide that binds to a hydrophobic groove containing an active-site Cys528 in the CRM1 protein. CRM1 inhibitors function largely by covalent modification of the active site Cys528 and prevent binding to the cargo protein NES. In the absence of a CRM1 inhibitor, CRM1 binds cooperatively to the NES of the cargo protein and RanGTP, forming a trimer that is actively transported out of the nucleus by facilitated diffusion. Nuclear export can be blocked by CRM1 inhibitors, NES peptide inhibitors or by preventing post-translational modification of cargo proteins. Clinical trials using the classic CRM1 inhibitor leptomycin B proved too toxic for patients; however, a new generation of less toxic small molecule inhibitors is being used in clinical trials in patients with both hematological malignancies and solid tumors. Additional trials are being initiated using small-molecule CRM1 inhibitors in combination with chemotherapeutics such as pegylated liposomal doxorubicin. In this review, we present evidence that combining the new CRM1 inhibitors with other classes of therapeutics may prove effective in the treatment of cancer. Potential combinatorial therapies discussed include the use of CRM1 inhibitors and the addition of alkylating agents (melphalan), anthracyclines (doxorubicin and daunomycin), BRAF inhibitors, platinum drugs (cisplatin and oxaliplatin), proteosome inhibitors (bortezomib and carfilzomib), or tyrosine-kinase inhibitors (imatinib). Also, the sequence of treatment may be important for combination therapy. We found that the most effective treatment regimen involved first priming the cancer cells with the CRM1 inhibitor followed by doxorubicin, bortezomib, carfilzomib, or melphalan. This order sensitized both de novo and acquired drug-resistant cancer cell lines.


Assuntos
Transporte Ativo do Núcleo Celular , Carioferinas/metabolismo , Neoplasias/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos , Humanos , Carioferinas/antagonistas & inibidores , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína Exportina 1
4.
Blood ; 122(13): 2251-61, 2013 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-23908471

RESUMO

Alloreactive donor T cells against host minor histocompatibility antigens (mHAs) cause graft-versus-host disease (GVHD) after marrow transplantation from HLA-identical siblings. We sought to identify and expand regulatory CD4 T cells (Tregs) specific for human mHAs in numbers and potency adequate for clinical testing. Purified Tregs from normal donors were stimulated by dendritic cells (DCs) from their HLA-matched siblings in the presence of interleukin 2, interleukin 15, and rapamycin. Male-specific Treg clones against H-Y antigens DBY, UTY, or DFFRY-2 suppressed conventional CD4 T cell (Tconv) response to the specific antigen. In the blood of 16 donors, we found a 24-fold (range, 8-fold to 39-fold) excess Tconvs over Tregs reactive against sibling mHAs. We expanded mHA-specific Tregs from 4 blood samples and 4 leukaphereses by 155- to 405-fold. Cultured Tregs produced allospecific suppression, maintained demethylation of the Treg-specific Foxp3 gene promoter, Foxp3 expression, and transforming growth factor ß production. The rare CD4 T conv and CD8 T cells in the end product were anergic. This is the first report of detection and expansion of potent mHA-specific Tregs from HLA-matched siblings in sufficient numbers for application in human transplant trials.


Assuntos
Técnicas de Cultura de Células/métodos , Doença Enxerto-Hospedeiro/prevenção & controle , Antígenos de Histocompatibilidade Menor/imunologia , Linfócitos T Reguladores/imunologia , Técnicas de Cocultura , Feminino , Citometria de Fluxo , Humanos , Masculino , Irmãos , Linfócitos T Reguladores/citologia , Transplante Homólogo
5.
CJEM ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39225970

RESUMO

The erector spinae plane (ESP) block is an increasingly utilized regional block in the emergency department, representing one effective alternative or adjunct to opioid analgesia in patients presenting with rib fractures. While there is growing interest, its widespread adoption faces hurdles, such as a lack of appropriate training resources. Gelatin-based phantoms to simulate human anatomy have been widely used to facilitate ultrasound-guided procedures, although no such model for the ESP block has yet been defined in the literature. To address this gap, we sought to design and assemble an inexpensive, simple to build, reusable phantom to simulate the sonographic anatomy of the posterior thoracic wall and serve as a task trainer for an ultrasound-guided ESP block. This novel phantom model reproduces an ultrasonographic fascial plane using a gelatin medium and 3D-printed thoracic spine with ribs allowing for needle guidance and hydrodissection.


RéSUMé: Le bloc plan érecteur-épine (ESP) est un bloc régional de plus en plus utilisé dans les services d'urgence, représentant une alternative efficace ou un complément à l'analgésie opioïde chez les patients présentant des fractures des côtes. Bien que l'intérêt grandisse, son adoption généralisée se heurte à des obstacles, tels que le manque de ressources de formation appropriées. Les fantômes à base de gélatine pour simuler l'anatomie humaine ont été largement utilisés pour faciliter les procédures guidées par ultrasons, bien qu'aucun modèle de ce type pour le bloc ESP n'ait encore été défini dans la littérature. Pour combler cette lacune, nous avons cherché à concevoir et assembler un fantôme peu coûteux, simple à construire et réutilisable pour simuler l'anatomie échographique de la paroi thoracique postérieure et servir d'entraîneur-tâche pour un bloc ESP guidé par ultrasons. Ce modèle fantôme reproduit un plan fascial échosonographique utilisant un milieu gélatineux et une colonne thoracique imprimée en 3D avec des nervures permettant le guidage de l'aiguille et l'hydrodissection.

6.
Acta Biomater ; 170: 39-52, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37714247

RESUMO

Despite over 50 years of silicate bioactive glass (SBG) research, commercial success, and 6000+ published articles, there remains a lack of understanding of how soluble silicate (Si) species released from SBGs influences cellular responses. Using a systematic approach, this article quantitatively compares the in vitro responses of cells to SBG dissolution products reported in the literature and determines if there is a Si concentration ([Si]) dependent effect on cell behaviour. Cell behavioural responses to SBGs [Si] in dissolution products included metabolic activity (reported in 52 % of articles), cell number (24 %), protein production (22 %), gene expression (22 %) and biomineralization (24 %). There was a difference in the [Si] reported to cause increased (desirable) cellular responses (median = 30.2 ppm) compared to the [Si] reported to cause decreased (undesirable) cellular responses (median = 52.0 ppm) (P ≤ 0.001). The frequency of undesirable outcomes increased with increasing [Si], with ∼3 times more negative outcomes reported above 52 ppm. We also investigated the effect of [Si] on specific cellular outcomes (e.g., metabolic activity, angiogenesis, osteogenesis), if cell type/species influenced these responses and the impact of other ions (Ca, P, Na) within the SBG dissolution media on cell behaviour. This review has, for the first time, quantitatively compared the cellular responses to SBGs from the literature, providing a quantitative overview of SBG in vitro practices and presents evidence of a range of [Si] where desirable cellular responses may be more likely (30-52 ppm). This review also demonstrates the need for greater standardisation of in vitro methodological approaches and recommends some minimum reporting standards. STATEMENT OF SIGNIFICANCE: This systematic review investigates the relationship between the concentration of Si released from Si-bioactive glasses (SBG) and in vitro cellular responses. Si releasing materials continue to be of considerable scientific, commercial, and medical interest (with 1500+ articles published in the last 3 years) but there is considerable variation in the reported biologically effective Si concentrations and on the importance of Si on cell behaviour. Despite the variation in methodological approaches, this article demonstrated statistical commonalities in the Si concentrations that cause desirable and undesirable cellular behaviours, suggesting a window where positive cellular outcomes are more likely. This review also provides a quantitative analysis of in vitro practices within the bioactive glass field and highlights the need for greater standardisation.

7.
Nat Med ; 29(4): 906-916, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36914893

RESUMO

Increasing evidence suggests that the gut microbiome may modulate the efficacy of cancer immunotherapy. In a B cell lymphoma patient cohort from five centers in Germany and the United States (Germany, n = 66; United States, n = 106; total, n = 172), we demonstrate that wide-spectrum antibiotics treatment ('high-risk antibiotics') prior to CD19-targeted chimeric antigen receptor (CAR)-T cell therapy is associated with adverse outcomes, but this effect is likely to be confounded by an increased pretreatment tumor burden and systemic inflammation in patients pretreated with high-risk antibiotics. To resolve this confounding effect and gain insights into antibiotics-masked microbiome signals impacting CAR-T efficacy, we focused on the high-risk antibiotics non-exposed patient population. Indeed, in these patients, significant correlations were noted between pre-CAR-T infusion Bifidobacterium longum and microbiome-encoded peptidoglycan biosynthesis, and CAR-T treatment-associated 6-month survival or lymphoma progression. Furthermore, predictive pre-CAR-T treatment microbiome-based machine learning algorithms trained on the high-risk antibiotics non-exposed German cohort and validated by the respective US cohort robustly segregated long-term responders from non-responders. Bacteroides, Ruminococcus, Eubacterium and Akkermansia were most important in determining CAR-T responsiveness, with Akkermansia also being associated with pre-infusion peripheral T cell levels in these patients. Collectively, we identify conserved microbiome features across clinical and geographical variations, which may enable cross-cohort microbiome-based predictions of outcomes in CAR-T cell immunotherapy.


Assuntos
Microbioma Gastrointestinal , Linfoma de Células B , Receptores de Antígenos Quiméricos , Humanos , Microbioma Gastrointestinal/genética , Imunoterapia , Imunoterapia Adotiva/efeitos adversos , Linfócitos T , Antígenos CD19
8.
Front Immunol ; 13: 1007042, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36225930

RESUMO

Chimeric antigen receptor (CAR)-T cells are engineered to identify and eliminate cells expressing a target antigen. Current manufacturing protocols vary between commercial CAR-T cell products warranting an assessment of these methods to determine which approach optimally balances successful manufacturing capacity and product efficacy. One difference between commercial product manufacturing methods is whether T cell engineering begins with fresh (unfrozen) patient cells or cells that have been cryopreserved prior to manufacture. Starting with frozen PBMC material allows for greater manufacturing flexibility, and the possibility of collecting and storing blood from patients prior to multiple lines of therapy. We prospectively analyzed if second generation anti-CD19 CAR-T cells with either CD28 or 4-1BB co-stimulatory domains have different phenotype or function when prepared side-by-side using fresh or cryopreserved PBMCs. We found that cryopreserved PBMC starting material is associated with slower CAR-T cell expansion during manufacture but does not affect phenotype. We also demonstrate that CAR-T cell activation, cytokine production and in vitro anti-tumor cytotoxicity were not different when CAR-T cells were manufactured from fresh or cryopreserved PBMC. As CAR-T cell therapy expands globally, the need for greater flexibility around the timing of manufacture will continue to grow. This study helps support the concept that cryopreservation of PBMCs could be the solution to these issues without compromising the quality of the final CAR-T product.


Assuntos
Receptores de Antígenos Quiméricos , Antígenos CD28 , Citocinas , Leucócitos Mononucleares/metabolismo , Receptores de Antígenos de Linfócitos T
9.
BMJ Open ; 12(8): e057852, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35948378

RESUMO

OBJECTIVES: To determine the diagnostic yield of screening patients for SARS-CoV-2 who were admitted with a diagnosis unrelated to COVID-19 and to identify risk factors for positive tests. DESIGN: Cohort from the Canadian COVID-19 Emergency Department Rapid Response Network registry. SETTING: 30 acute care hospitals across Canada. PARTICIPANTS: Patients hospitalised for non-COVID-19-related diagnoses who were tested for SARS-CoV-2 between 1 March and 29 December 2020. MAIN OUTCOME: Positive nucleic acid amplification test for SARS-CoV-2. OUTCOME MEASURE: Diagnostic yield. RESULTS: We enrolled 15 690 consecutive eligible adults who were admitted to hospital without clinically suspected COVID-19. Among these patients, 122 tested positive for COVID-19, resulting in a diagnostic yield of 0.8% (95% CI 0.64% to 0.92%). Factors associated with a positive test included presence of fever, being a healthcare worker, having a positive household contact or institutional exposure, and living in an area with higher 7-day average incident COVID-19 cases. CONCLUSIONS: Universal screening of hospitalised patients for COVID-19 across two pandemic waves had a low diagnostic yield and should be informed by individual-level risk assessment in addition to regional COVID-19 prevalence. TRIAL REGISTRATION NUMBER: NCT04702945.


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , COVID-19/diagnóstico , COVID-19/epidemiologia , Teste para COVID-19 , Canadá/epidemiologia , Hospitais , Humanos , Pandemias/prevenção & controle
10.
J Am Coll Emerg Physicians Open ; 3(6): e12868, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36579029

RESUMO

Objective: To risk-stratify COVID-19 patients being considered for discharge from the emergency department (ED). Methods: We conducted an observational study to derive and validate a clinical decision rule to identify COVID-19 patients at risk for hospital admission or death within 72 hours of ED discharge. We used data from 49 sites in the Canadian COVID-19 Emergency Department Rapid Response Network (CCEDRRN) between March 1, 2020, and September 8, 2021. We randomly assigned hospitals to derivation or validation and prespecified clinical variables as candidate predictors. We used logistic regression to develop the score in a derivation cohort and examined its performance in predicting short-term adverse outcomes in a validation cohort. Results: Of 15,305 eligible patient visits, 535 (3.6%) experienced the outcome. The score included age, sex, pregnancy status, temperature, arrival mode, respiratory rate, and respiratory distress. The area under the curve was 0.70 (95% confidence interval [CI] 0.68-0.73) in derivation and 0.71 (95% CI 0.68-0.73) in combined derivation and validation cohorts. Among those with a score of 3 or less, the risk for the primary outcome was 1.9% or less, and the sensitivity of using 3 as a rule-out score was 89.3% (95% CI 82.7-94.0). Among those with a score of ≥9, the risk for the primary outcome was as high as 12.2% and the specificity of using 9 as a rule-in score was 95.6% (95% CI 94.9-96.2). Conclusion: The CCEDRRN COVID discharge score can identify patients at risk of short-term adverse outcomes after ED discharge with variables that are readily available on patient arrival.

11.
CMAJ Open ; 9(1): E261-E270, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33731427

RESUMO

BACKGROUND: Emergency physicians lack high-quality evidence for many diagnostic and treatment decisions made for patients with suspected or confirmed coronavirus disease 2019 (COVID-19). Our objective is to describe the methods used to collect and ensure the data quality of a multicentre registry of patients presenting to the emergency department with suspected or confirmed COVID-19. METHODS: This methodology study describes a population-based registry that has been enrolling consecutive patients presenting to the emergency department with suspected or confirmed COVID-19 since Mar. 1, 2020. Most data are collected from retrospective chart review. Phone follow-up with patients at 30 days captures the World Health Organization clinical improvement scale and contextual, social and cultural variables. Phone follow-up also captures patient-reported quality of life using the Veterans Rand 12-Item Health Survey at 30 days, 60 days, 6 months and 12 months. Fifty participating emergency departments from 8 provinces in Canada currently enrol patients into the registry. INTERPRETATION: Data from the registry of the Canadian COVID-19 Emergency Department Rapid Response Network will be used to derive and validate clinical decision rules to inform clinical decision-making, describe the natural history of the disease, evaluate COVID-19 diagnostic tests and establish the real-world effectiveness of treatments and vaccines, including in populations that are excluded or underrepresented in clinical trials. This registry has the potential to generate scientific evidence to inform our pandemic response, and to serve as a model for the rapid implementation of population-based data collection protocols for future public health emergencies. TRIAL REGISTRATION: Clinicaltrials.gov, no. NCT04702945.


Assuntos
COVID-19 , Medicina de Emergência , Sistema de Registros , COVID-19/diagnóstico , COVID-19/terapia , Canadá , Confiabilidade dos Dados , Coleta de Dados , Gerenciamento de Dados , Serviço Hospitalar de Emergência , Medicina de Emergência Baseada em Evidências , Seguimentos , Humanos , Armazenamento e Recuperação da Informação , Medidas de Resultados Relatados pelo Paciente , Estudos Prospectivos , Qualidade de Vida , Estudos Retrospectivos , SARS-CoV-2 , Telefone
12.
Mol Cancer Ther ; 8(4): 794-801, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19372552

RESUMO

Histone deacetylases (HDAC) may have a prominent role in the development of cancer and the response to anticancer therapy. However, the therapeutic relevance and tissue specificity of individual HDAC enzymes remain largely unknown. HDAC inhibitors may function as sensitizing agents to chemotherapies that target DNA through their effects on chromatin structure and plasticity. Here, we report a new role for HDAC2 as a regulator of chromatin compaction status and the mediator of HDAC inhibitor-induced sensitization to chemotherapy. The selective depletion of HDAC2 by small interfering RNA led to reduced expression of heterochromatin maintenance proteins and morphologic changes indicative of chromatin decondensation. Furthermore, depletion of HDAC2 but not HDAC1 or HDAC6 was sufficient to sensitize breast cancer cells to topoisomerase inhibitor-induced apoptosis. The levels of HDAC2 expression appear to correlate with the degree of HDAC inhibitor-induced histone acetylation in a surrogate tissue in patients. These data suggest that HDAC2 may be a relevant pharmacologic and biological target for combination therapy involving drugs that target DNA.


Assuntos
Neoplasias da Mama/genética , Cromatina/metabolismo , DNA de Neoplasias/metabolismo , DNA/genética , Histona Desacetilases/fisiologia , Proteínas Repressoras/fisiologia , Acetilação , Antibióticos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Western Blotting , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , DNA/metabolismo , Inibidores Enzimáticos/farmacologia , Epirubicina/farmacologia , Perfilação da Expressão Gênica , Histona Desacetilase 1 , Histona Desacetilase 2 , Desacetilase 6 de Histona , Histonas , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , RNA Interferente Pequeno/farmacologia , Células Tumorais Cultivadas
13.
Microbiol Resour Announc ; 9(27)2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32616646

RESUMO

Roseimicrobium sp. strain ORNL1 is a soil bacterium that belongs to the phylum Verrucomicrobia and was isolated from the rhizosphere of a forest Eastern cottonwood tree, Populus deltoides, in Tennessee. Its 7.9-Mb chromosome was completely sequenced using PacBio long reads and is predicted to encode 6,288 proteins and 76 RNAs.

14.
Microbiol Resour Announc ; 9(27)2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32616649

RESUMO

Starkeya sp. strain ORNL1 is an alphaproteobacterium isolated from the rhizosphere of an Eastern cottonwood tree. Starkeya spp. are physiologically versatile, using a wide range of nutritional and energetic resources and serving important ecological roles in carbon and sulfur cycling. The 6.3-Mb chromosome of Starkeya sp. strain ORNL1 was completely sequenced and will help in understanding nutrient cycles.

15.
Materials (Basel) ; 13(7)2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32272786

RESUMO

Biological structures have emerged through millennia of evolution, and nature has fine-tuned the material properties in order to optimise the structure-function relationship. Following this paradigm, polydopamine (PDA), which was found to be crucial for the adhesion of mussels to wet surfaces, was hence initially introduced as a coating substance to increase the chemical reactivity and surface adhesion properties. Structurally, polydopamine is very similar to melanin, which is a pigment of human skin responsible for the protection of underlying skin layers by efficiently absorbing light with potentially harmful wavelengths. Recent findings have shown the subsequent release of the energy (in the form of heat) upon light excitation, presenting it as an ideal candidate for photothermal applications. Thus, polydopamine can both be used to (i) coat nanoparticle surfaces and to (ii) form capsules and ultra-small (nano)particles/nanocomposites while retaining bulk characteristics (i.e., biocompatibility, stability under UV irradiation, heat conversion, and activity during photoacoustic imaging). Due to the aforementioned properties, polydopamine-based materials have since been tested in adhesive and in energy-related as well as in a range of medical applications such as for tumour ablation, imaging, and drug delivery. In this review, we focus upon how different forms of the material can be synthesised and the use of polydopamine in biological and biomedical applications.

16.
Cancer Res ; 80(23): 5344-5354, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33023948

RESUMO

High-dose chemotherapy with melphalan followed by autologous transplantation is a first-line treatment for multiple myeloma. Here, we present preclinical evidence that this treatment may be significantly improved by the addition of exportin 1 inhibitors (XPO1i). The XPO1i selinexor, eltanexor, and KOS-2464 sensitized human multiple myeloma cells to melphalan. Human 8226 and U266 multiple myeloma cell lines and melphalan-resistant cell lines (8226-LR5 and U266-LR6) were highly sensitized to melphalan by XPO1i. Multiple myeloma cells from newly diagnosed and relapsed/refractory multiple myeloma patients were also sensitized by XPO1i to melphalan. In NOD/SCIDγ mice challenged with either parental 8226 or U266 multiple myeloma and melphalan-resistant multiple myeloma tumors, XPO1i/melphalan combination treatments demonstrated stronger synergistic antitumor effects than single-agent melphalan with minimal toxicity. Synergistic cell death resulted from increased XPO1i/melphalan-induced DNA damage in a dose-dependent manner and decreased DNA repair. In addition, repair of melphalan-induced DNA damage was inhibited by selinexor, which decreased melphalan-induced monoubiquitination of FANCD2 in multiple myeloma cells. Knockdown of FANCD2 was found to replicate the effect of selinexor when used with melphalan, increasing DNA damage (γH2AX) by inhibiting DNA repair. Thus, combination therapies that include selinexor or eltanexor with melphalan may have the potential to improve treatment outcomes of multiple myeloma in melphalan-resistant and newly diagnosed patients. The combination of selinexor and melphalan is currently being investigated in the context of high-dose chemotherapy and autologous transplant (NCT02780609). SIGNIFICANCE: Inhibition of exportin 1 with selinexor synergistically sensitizes human multiple myeloma to melphalan by inhibiting Fanconi anemia pathway-mediated DNA repair.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carioferinas/antagonistas & inibidores , Mieloma Múltiplo/tratamento farmacológico , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Dano ao DNA , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/genética , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/metabolismo , Humanos , Hidrazinas/administração & dosagem , Hidrazinas/farmacologia , Carioferinas/metabolismo , Melfalan/administração & dosagem , Camundongos Endogâmicos NOD , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Nestina/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Triazóis/administração & dosagem , Triazóis/farmacologia , Ubiquitinação/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína Exportina 1
17.
Clin Cancer Res ; 26(1): 54-60, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31636097

RESUMO

PURPOSE: Induction chemotherapy results in complete remission (CR) rates of 20% to 50% among patients with poor-risk AML. Selinexor is an oral selective inhibitor of nuclear export with promising single-agent activity. By inhibiting the primary export protein, XPO1, selinexor localizes and activates tumor suppressor proteins in the nucleus and inhibits DNA damage repair, rationalizing combination with DNA-damaging agents. PATIENTS AND METHODS: This was a single-arm phase I clinical trial of selinexor combined with cytarabine and daunorubicin (7+3). Dose escalation was selinexor alone (3+3) with an expansion at the MTD. Cohorts 1 and 2 received 60 and 80 mg orally, respectively, twice weekly during induction. Consolidation cycles (≤ 2) with selinexor at induction dose plus 5+2 were allowed for patients who achieved CR. MTD and recommended phase II dose of selinexor were the primary endpoints. RESULTS: Twenty-one patients with poor-risk AML were enrolled. All 21 patients were included in the safety evaluations and survival analyses (4 in each of 2 cohorts; 13 in the expansion); 8 (53%) of the 19 patients evaluable for response achieved CR/CRi. MTD was not reached. Selinexor 80 mg (orally, twice weekly) was used in the expansion phase. The most common grade 3/4 nonhematologic treatment-emergent adverse events were febrile neutropenia (67%), diarrhea (29%), hyponatremia (29%), and sepsis (14%). At median follow-up (28.9 months), 38% of patients were alive. Median overall survival was 10.3 months. CONCLUSIONS: Selinexor plus 7+3 is a safe regimen for patients with newly diagnosed poor-risk AML and warrants further investigation in a larger clinical trial.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Adulto , Idoso , Citarabina/administração & dosagem , Daunorrubicina/administração & dosagem , Feminino , Humanos , Hidrazinas/administração & dosagem , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/patologia , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Segurança do Paciente , Taxa de Sobrevida , Distribuição Tecidual , Resultado do Tratamento , Triazóis/administração & dosagem
18.
Microbiol Resour Announc ; 8(46)2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31727704

RESUMO

Terriglobus albidus strain ORNL is a heterotrophic soil acidobacterium isolated from the rhizosphere of an Eastern cottonwood tree (Populus deltoides) in Tennessee. Its 6.4-Mb chromosome was completely sequenced using PacBio long reads, and it encodes 5,010 proteins and 53 RNAs.

19.
Curr Med Chem ; 15(26): 2648-55, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18991627

RESUMO

Expression levels of intact tumor suppressor proteins and molecular targets of anti-neoplastic agents are critical in defining cancer cell drug sensitivity; however, the intracellular location of a specific protein may be as important. Many tumor suppressor proteins must be present in the cell nucleus to perform their policing activities or for the cell to respond to chemotherapeutic agents. Nuclear proteins needed to prevent cancer initiation or progression or to optimize chemotherapeutic response include the tumor suppressor proteins p53, APC/beta-catenin, and FOXO family genes; negative regulators of cell cycle progression and survival such as p21(CIP1) and p27(KIP1;) and chemotherapeutic targets such as DNA topoisomerases I and IIalpha. Mislocalization of a nuclear protein into the cytoplasm can render it ineffective as a tumor suppressor or as a target for chemotherapy. Blocking nuclear export of any or all of these proteins may restore tumor suppression or apoptosis or, for topoisomerases I and IIalpha, reverse drug resistance to inhibitors of these enzymes. During disease progression or in response to the tumor environment, cancer cells appear to acquire intracellular mechanisms to export anti-cancer nuclear proteins. These mechanisms generally involve modification of nuclear proteins, causing the proteins to reveal leucine-rich nuclear export signal protein sequences. Subsequent export is mediated by CRM1. This review defines the general processes involved in nuclear export mediated by CRM1/RanGTP (exportin/XPO1), examines the functions of individual tumor suppressor nuclear proteins and nuclear targets of chemotherapy, and explores potential mechanisms of cancer cells to induce export of these proteins. Novel drugs that could potentially counteract nuclear export of specific proteins are also discussed.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Carioferinas/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Transporte Ativo do Núcleo Celular , Sequência de Aminoácidos , Humanos , Dados de Sequência Molecular , Proteína Exportina 1
20.
Cancer Res ; 66(10): 5007-11, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16707421

RESUMO

To investigate transcriptional activation of the breast cancer resistance protein gene (BCRP/ABCG2), we examined the 5' untranslated region of BCRP mRNA in cell lines with high BCRP transcriptional activity and in normal tissues. Human choriocarcinoma cells with high endogenous BCRP expression (JAR and BeWo) and human cancer cells (MCF-7 and Igrov1) and their BCRP-overexpressing, drug-selected, multidrug-resistant derivatives (MCF-7/AdrVp, Igrov1/MX3, and Igrov1/T8) were studied. Rapid amplification of 5'-cDNA ends-PCR (5'RACE-PCR) revealed at least three novel forms of the untranslated exon 1 (E1a, E1b, and E1c) that are spliced to a common exon 2, with differential expression of these splice variants in the drug-selected cell lines. Additionally, sequence analysis of the 5'RACE-PCR products revealed multiple transcriptional start sites for each variant, particularly in the drug-selected cells. The E1c isoform predominated in drug-selected MCF-7 cell lines and was translated more efficiently in MCF-7 cells than the E1a isoform. Varying patterns of expression of the exon 1 isoforms were observed in a variety of human tissues, suggesting that tissue-specific alternative promoters of BCRP exist. In summary, we find that BCRP overexpression in the drug-selected cells is accompanied by multiple transcriptional start sites and predominance of the more efficiently translated E1c isoform. The exon 1 variation we observe suggests that alternative promoters of the BCRP gene exist.


Assuntos
Regiões 5' não Traduzidas/genética , Transportadores de Cassetes de Ligação de ATP/genética , Neoplasias da Mama/genética , Proteínas de Neoplasias/genética , Neoplasias Ovarianas/genética , RNA Mensageiro/genética , Regiões 5' não Traduzidas/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/biossíntese , Transportadores de Cassetes de Ligação de ATP/metabolismo , Sequência de Bases , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Coriocarcinoma/tratamento farmacológico , Coriocarcinoma/genética , Coriocarcinoma/metabolismo , Éxons , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Dados de Sequência Molecular , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Regiões Promotoras Genéticas , Biossíntese de Proteínas , Isoformas de Proteínas , RNA Mensageiro/biossíntese , Ativação Transcricional , Regulação para Cima
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