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1.
Front Public Health ; 12: 1349552, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38544733

RESUMO

Introduction: Mouse models of radiation injury are critical to the development of medical countermeasures (MCMs) against radiation. Now that MCMs against hematopoietic acute radiation syndrome (H-ARS) have achieved regulatory approval, attention is shifting to develop MCMs against the adverse effects of gastrointestinal acute radiation syndrome (GI-ARS) and delayed effects of acute radiation exposure (DEARE). The C57L/J mouse model of partial body irradiation (PBI) with 2.5% bone marrow shielding (BM2.5) is being leveraged to examine both GI-ARS and DEARE effects. Within days of PBI, mice may develop H- and GI-ARS followed several months later by DEARE as a multi-organ injury, which typically involves the lung and kidney (L- and K-DEARE, respectively). The objective of this manuscript is to describe the dose response relationship and progression of radiation injury in the C57L/J mouse and to evaluate its suitability for use in DEARE MCM testing. Materials and methods: In two separate studies conducted over 2 years, male and female C57L/J mice were exposed to PBI BM2.5 with one hindlimb shielded from radiation, representing ~2.5% bone marrow shielding/sparing. Mice were X-ray irradiated at doses ranging from 9 to 13 Gy at 10 to 12 weeks of age for the purposes of assessing ARS survival at 30 days and DEARE survival at 182 days post-irradiation. Clinical indicators of ARS and DEARE were determined by clinical observations, body weights, hematology, clinical chemistry, magnetic resonance imaging (MRI) of lung, and histopathology of selected tissues. Results: C57L/J mice developed canonical ARS responses of hematopoietic atrophy and gastrointestinal injury resulting in dose dependent mortality at doses ≥11 Gy between 1- and 15-days post-irradiation. In animals that survived ARS, DEARE associated mortality occurred in dose dependent fashion at ≥9 Gy for both sexes between 60- and 159-days post-irradiation with histopathology examinations indicating lung injury as the primary cause of death in moribund animals. Conclusion: The PBI BM2.5 C57L/J mouse model reliably produced known H- and GI-ARS effects at doses greater than those resulting in DEARE effects. Because of this, the C57L/J mouse can be used to test MCMs against L-DEARE injury, while avoiding ARS associated mortality.


Assuntos
Síndrome Aguda da Radiação , Medula Óssea , Masculino , Feminino , Camundongos , Animais , Medula Óssea/patologia , Medula Óssea/efeitos da radiação , Síndrome Aguda da Radiação/etiologia , Síndrome Aguda da Radiação/patologia , Modelos Animais de Doenças , Pulmão/patologia
2.
Bioeng Transl Med ; 9(1): e10605, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38193126

RESUMO

Primary T cell has been transformed into a cell-based delivery platform that synthesizes complex biologics at the disease site with spatiotemporal resolution. This broadly applicable technology can circumvent toxicities due to systemic administration of biologics that necessitates the use of high doses and may diffuse to the healthy tissues. Its clinical translation, however, has been impeded by manufacturing bottlenecks. In this work, a range of process parameters were investigated for increasing the production yield of the primary T cells engineered for delivery function. Compared to the common spinoculation-based method, the transduction yield was enhanced ~2.5-fold by restricting the transduction reaction volume for maximizing the lentivector-to-T-cell contact. Cell density and cytokines used in the expansion process were adjusted to achieve >100-fold expansion of the T-cell-based delivery platform in 14 days, and the function of these cells was validated in vivo using intraperitoneally implanted tumor cells. The primary T-cell-based delivery platform has human applications because it can be scaled and administrated to express a broad range of therapeutic proteins (e.g., cytokines, interferons, enzymes, agonists, and antagonists) at the disease site, obviating the need for systemic delivery of large doses of these proteins.

3.
Bioeng Transl Med ; 8(3): e10508, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37206248

RESUMO

We have developed a serology test platform for identifying individuals with prior exposure to specific viral infections and provide data to help reduce public health risks. The serology test composed of a pair of cell lines engineered to express either a viral envelop protein (Target Cell) or a receptor to recognize the Fc region of an antibody (Reporter Cell), that is, Diagnostic-Cell-Complex (DxCell-Complex). The formation of an immune synapse, facilitated by the analyte antibody, resulted into a dual-reporter protein expression by the Reporter Cell. We validated it with human serum with confirmed history of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. No signal amplification steps were necessary. The DxCell-Complex quantitatively detected the target-specific immunoglobulin G (IgG) within 1 h. Validation with clinical human serum containing SARS-CoV-2 IgG antibodies confirmed 97.04% sensitivity and 93.33% specificity. The platform can be redirected against other antibodies. Self-replication and activation-induced cell signaling, two attributes of the cell, will enable rapid and cost-effective manufacturing and its operation in healthcare facilities without requiring time-consuming signal amplification steps.

4.
Int J Radiat Oncol Biol Phys ; 117(3): 705-717, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37224926

RESUMO

PURPOSE: Patients exposed to acute high doses of ionizing radiation are susceptible to dose-dependent bone marrow depression with resultant pancytopenia. Romiplostim (RP; Nplate) is a recombinant thrombopoietin receptor agonist protein that promotes progenitor megakaryocyte proliferation and platelet production and is an approved treatment for patients with chronic immune thrombocytopenia. The goal of our study was to evaluate the postirradiation survival and hematologic benefits of a single dose of RP with or without pegfilgrastim (PF; Neulasta, granulocyte colony stimulating factor) by conducting a well-controlled, treatment-concealed, good laboratory practice-compliant study in rhesus macaques that was compliant with the United States Food and Drug Administration Animal Rule regulatory approval pathway. METHODS AND MATERIALS: Irradiated male and female rhesus macaques (20/sex in each of 3 groups: control, RP, and RP + PF) were subcutaneously administered vehicle or RP (5 mg/kg, 10 mL/kg) on day 1 in the presence or absence of 2 doses of PF (0.3 mg/kg, 0.03 mL/kg, days 1 and 8). Total body radiation (680 cGy, 50 cGy/min from cobalt-60 gamma ray source) occurred 24 ± 2 hours previously at a dose targeting 70% lethality for the control cohort over 60 days. The study examined 60-day survival postirradiation as the primary endpoint. Secondary endpoints included incidence, severity, and duration of thrombocytopenia and neutropenia, other hematology parameters, coagulation parameters, and body weight change to provide insights into potential mechanisms of action. RESULTS: Compared with sham-treated controls, treated animals demonstrated a 40% to 55% survival benefit compared with controls, less severe clinical signs, reduced incidence of thrombocytopenia and/or neutropenia, earlier hematologic recovery, and reduced morbidity from bacterial infection. CONCLUSIONS: These results were pivotal in obtaining Food and Drug Administration approval in January 2021 for RP's new indication as a single administration therapy to increase survival in adults and pediatric patients acutely exposed to myelosuppressive doses of radiation.


Assuntos
Hematologia , Neutropenia , Exposição à Radiação , Trombocitopenia , Adulto , Animais , Humanos , Masculino , Feminino , Criança , Macaca mulatta , Proteínas Recombinantes , Trombocitopenia/tratamento farmacológico , Trombocitopenia/etiologia , Neutropenia/tratamento farmacológico
5.
Int J Radiat Biol ; 99(7): 1080-1095, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36930794

RESUMO

PURPOSE: To describe the dose response relationship and natural history of radiation injury in the Wistar rat and its suitability for use in medical countermeasures (MCM) testing. MATERIALS & METHODS: In two separate studies, male and female rats were exposed to partial body irradiation (PBI) with 5% bone marrow sparing. Animals were X-ray irradiated from 7 to 12 Gy at 7-10 weeks of age. Acute radiation syndrome (ARS) survival at 30 days and delayed effects of acute radiation exposure (DEARE) survival at 182 days were assessed. Radiation effects were determined by clinical observations, body weights, hematology, clinical chemistry, magnetic resonance imaging of lung, whole-body plethysmography, and histopathology. RESULTS: Rats developed canonical ARS responses of hematopoietic atrophy and gastrointestinal injury resulting in mortality at doses ≥8Gy in males and ≥8.5 Gy in females. DEARE mortality occurred at doses ≥8Gy for both sexes. Findings indicate lung, kidney, and/or liver injury, and persistent hematological dysregulation, revealing multi-organ injury as a DEARE. CONCLUSION: The Wistar rat PBI model is suitable for testing MCMs against hematopoietic and gastrointestinal ARS. DEARE multi-organ injury occurred in both sexes irradiated with 8-9Gy, also suggesting suitability for polypharmacy studies addressing the combination of ARS and DEARE injury.


Assuntos
Síndrome Aguda da Radiação , Sistema Hematopoético , Masculino , Feminino , Ratos , Animais , Medula Óssea/efeitos da radiação , Ratos Wistar , Síndrome Aguda da Radiação/etiologia , Síndrome Aguda da Radiação/patologia , Trato Gastrointestinal/efeitos da radiação
6.
Bioeng Transl Med ; 8(2): e10434, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36925710

RESUMO

This work reports on an engineered cell that-when electrically stimulated-synthesizes a desired protein, that is, ES-Biofactory. The platform has been used to express interferon (IFN)-ß as a universal antiviral protein. Compelling evidence indicates the inevitability of new pandemics and drives the need for a pan-viral intervention that may be quickly deployed while more specific vaccines are in development. Toward this goal, a fast-growing mammalian cell (Chassis) has been engineered with multiple synthetic elements. These include-(1) a voltage-gated Ca2+ channel (Voltage-Sensor) that, upon sensing the electric field, activates the (2) Ca2+-mediated signaling pathway (Actuator) to upregulate (3) IFN-ß, via an engineered antiviral transgene (Effector), that is, ES-Biofactory➔IFN-ß. The antiviral effects of the ES-Biofactory➔IFN-ß have been validated on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected cells. The irradiated ES-Biofactory, that does not exhibit oncogenic capacity, continues to exert antiviral effect. The resulting ES-Biofactory➔IFN-ß uses a novel signaling pathway that, unlike the natural IFN synthesis pathway, is not subject to viral interference. Once clinically validated, the ES-Biofactory will be a universal antiviral cell therapy that can be immediately deployed in the event of an outbreak. The platform may also be useful in treating other diseases including cancer and autoimmune disorders.

7.
Microbiol Spectr ; 10(4): e0073122, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-35852348

RESUMO

We have engineered a cell that can be used for diagnosing active severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Isolation of individuals with active infections offers an effective solution for mitigating pandemics. However, the implementation of this practice requires robust infrastructure for rapid and intuitive testing, which is currently missing in our communities. To address this need, we engineered a fast-growing cell line into a cell-based antigen test platform for emerging viruses, i.e., DxCell, that can be rapidly deployed in decentralized health care facilities for continuous testing. The technology was characterized using cells engineered to present spike glycoprotein of SARS-CoV-2 (SARS-CoV-2-Sgp-cells) and Calu-3 host cells infected with competent SARS-CoV-2. Preclinical validation was conducted by directly incubating the DxCell with oropharyngeal swabs from mice infected with SARS-CoV-2. No sample preparation steps are necessary. The DxCell quantitatively detected the SARS-CoV-2-Sgp-cells within 1 h (P < 0.02). Reporter signal was proportional to the number of SARS-CoV-2-Sgp-cells, which represents the infection burden. The SARS-CoV-2 DxCell antigen test was benchmarked against quantitative PCR (qPCR) test and accurately differentiated between infected (n = 8) and control samples (n = 3) (P < 0.05). To demonstrate the broad applicability of the platform, we successfully redirected its specificity and tested its sensing function with cells engineered to present antigens from other viruses. In conclusion, we have developed an antigen test platform that capitalizes on the two innate functions of the cell, self-replication and activation-induced cell signaling. These provide the DxCell key advantages over existing technologies, e.g., label-free testing without sample processing, and will facilitate its implementation in decentralized health care facilities. IMPORTANCE Pandemic mitigation requires continuous testing of symptomatic or asymptomatic individuals with rapid turnaround time, and lack of this capability in our community has prolonged pandemic duration leading to obliteration of world economies. The DxCell platform is a cell-based self-replicative antigen test that detects molecular signatures of the target pathogen and can be distributed in small quantities to testing facilities for expansion on site to the desired volume. In this work, we directed this platform to target SARS-CoV-2. Unlike the PCR detection of viral mRNA that requires trained personnel, the DxCell does not require any sample preparation or signal amplification step and introduces an opportunity for a decentralized testing network.


Assuntos
COVID-19 , Animais , COVID-19/diagnóstico , Teste para COVID-19 , Camundongos , Pandemias , SARS-CoV-2/genética , Manejo de Espécimes
8.
Nicotine Tob Res ; 24(11): 1811-1820, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-35575085

RESUMO

INTRODUCTION: Although e-cigarettes are not a federally approved tobacco cessation aid in the United States, many smokers use them to quit or cut down on smoking. Tailored behavioral support could improve rates of complete smoking cessation for those individuals. AIMS AND METHODS: A novel behavioral treatment to help dual cigarette and e-cigarette users quit smoking was tested in a randomized pilot with a state tobacco quitline. Ninety-six dual users of cigarettes and e-cigarettes were recruited from incoming state quitline callers and randomized to receive enhanced e-cigarette coaching (EEC) or quitline treatment as usual (TAU) to examine EEC feasibility and acceptability. Outcomes at 3 months were treatment satisfaction, engagement, beliefs, and smoking cessation. This pilot was not powered to detect differences in quit rates. RESULTS: Sixty-nine percent responded to the 3-month survey. EEC treatment satisfaction was noninferior to TAU: 93.8% (30/32) of EEC and 73.5% (25/34) of TAU reported being "very satisfied" or "satisfied" with treatment, respectively. EEC participants completed more coaching calls than TAU (M = 3.4 vs. M = 2.7, p = .03), and the majority in both groups elected to receive nicotine replacement therapy (EEC: 100%, TAU: 94%, p = .24). With missing data imputed as smoking, intent-to-treat 7-day point prevalence smoking abstinence rates were 41.3% (19/46) for EEC and 28.0% (14/50) for TAU (p = .20). CONCLUSIONS: The EEC quitline intervention for dual cigarette and e-cigarette users demonstrated high levels of treatment satisfaction and engagement. This pilot was not powered to detect significant differences in smoking cessation; however, cessation rates were promising and warrant evaluation in a fully powered trial. IMPLICATIONS: If this scalable behavioral treatment to help dual cigarette and e-cigarette users quit smoking proves to be effective in a larger trial, quitlines could implement this harm reduction approach to improve outcomes for callers who already use e-cigarettes and are planning to use them while quitting smoking.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Abandono do Hábito de Fumar , Vaping , Humanos , Vaping/epidemiologia , Dispositivos para o Abandono do Uso de Tabaco , Projetos Piloto
9.
Contemp Clin Trials Commun ; 24: 100845, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34568637

RESUMO

BACKGROUND: Approximately 57,000 dual users of cigarettes and e-cigarettes call state tobacco quitlines in the U.S. each year. METHODS: This paper describes a behavioral intervention for dual users of cigarettes and e-cigarettes designed to increase cigarette abstinence. It also presents baseline data from a randomized pilot comparing the Enhanced E-cigarette Coaching (EEC) intervention with quitline treatment as usual (TAU). Oklahoma Tobacco Helpline callers were recruited at registration and randomized to EEC (n = 46) or TAU (n = 50). Treatment included 5 coaching calls and free nicotine replacement therapy (NRT). EEC treatment included enhanced e-cigarette assessment, education, a shared decision-making quit plan development approach, and tailored behavioral support. RESULTS: Participants averaged 40.6 years of age and 19.2 cigarettes per day; 85% smoked daily, 48% vaped daily, and 53% reported medium to high e-cigarette dependence. Most reported using e-cigarettes to quit (43%) or to cut down (26%) on smoking. Most had previously tried to quit smoking (91%) and had tried FDA-approved cessation medications (79%). Beliefs about vaping, NRT, and smoking included misinformation. After discussing the relative risks of NRT, vaping, and smoking, most EEC participants (89%) selected a quit plan that incorporated both NRT and vaping. CONCLUSIONS: At baseline, most participants reported a history of failed quit attempts with NRT and were vaping to quit or cut down on smoking, but they may need more support to completely quit smoking. If the EEC improves smoking outcomes, it would provide needed guidance on behavioral support best practices for individuals who vape and want to quit smoking.

10.
Adv Biol (Weinh) ; 5(7): e2000298, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33871182

RESUMO

The NK-92MI, a fast-growing cytolytic cell line with a track record of exerting clinical efficacy, is transformed into a vector for synthesizing calibrated amounts of desired engineered proteins at our disease site, that is, NK-cell Biofactory. This provides an allogeneic option to the previously published T-cell-based living vector that is limited by high manufacturing cost and product variability. The modularity of this pathway, which combines a "target" receptor with an "effector" function, enables reprogramming of the NK-cell Biofactory to target diseases with specific molecular biomarkers, such as cancer, viral infections, or auto-immune disorders, and overcome barriers that may affect the advancement of NK-cell therapies.


Assuntos
Neoplasias , Receptores de Antígenos Quiméricos , Humanos , Imunoterapia Adotiva , Células Matadoras Naturais , Linfócitos T
11.
Int J Radiat Biol ; 97(2): 126-130, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33259246

RESUMO

PURPOSE: Harmonized animal models are an indispensable tool for the development of safe and effective medical countermeasures (MCMs) against radiation injury, and rhesus macaques (referred herein as NHPs) play a critical role in FDA approval of radiation medical countermeasures for acute and delayed radiation syndromes. Reliance on such models requires that they be well characterized, which consists, in part, of a reproducible dose to mortality response relationship (DRR). However, data describing the DRR for both male and female NHPs from the same study are scarce. Furthermore, the level of supportive care and the use of blood transfusions may shift the DRR, yet such information can be difficult to compare across publications. To address these knowledge gaps, the DRRs of two different NHP total body irradiation (TBI) models are compared in this paper, one which is reliant on the use of male animals provided blood transfusions, and the other which incorporates both sexes wherein animals are not provided transfusions. MATERIALS AND METHODS: Studies were conducted using NHPs (Macacca mulatta) receiving TBI, with survival reported over a 60 days. Two primary studies, incorporating both male and female animals not receiving blood transfusions as a provision of supportive care, were compared to two previously published studies, which incorporated only male animals provided blood transfusions as a part of the supportive care regimen. Criterion for euthanasia, and all other provisions of supportive care were comparable. Linear probit plots estimating the lethal dose (LD) and upper and lower limits of the 95% confidence interval (CI) for 10, 30, 50, 70 and 90% mortality, were compared between individual studies and the two models presented. RESULTS: Comparison of probit estimates reveals two important findings. (1) Females have higher mortality than males at identical radiation doses, and (2) blood transfusions increased survival of male animals at lower doses but not at high doses of radiation exposure. CONCLUSIONS: The use of single sex animal models may lead to an incomplete understanding of potential sex differences in the dose to mortality response of the TBI model. Consistent use of both sexes and type of supportive care will improve the transferability and reliability of NHP-TBI models currently in use, assist in the selection of radiation doses for single dose lethality studies, and allow investigators to determine the effectiveness of a particular MCM.


Assuntos
Modelos Animais , Irradiação Corporal Total , Animais , Transfusão de Sangue , Relação Dose-Resposta à Radiação , Feminino , Macaca mulatta , Masculino , Dosagem Radioterapêutica , Caracteres Sexuais , Irradiação Corporal Total/mortalidade
12.
Adv Biosyst ; 4(6): e1900288, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32390316

RESUMO

A process for maximizing the titer of lentivirus particles, deemed to be a necessity for transducing primary cells, is developed. Lentivirus particles, with a set of transgenes encoding an artificial cell-signaling pathway, are used to transform primary T cells as vectors for calibrated synthesis of desired proteins in situ, that is, T-cell biofactory cells. The process is also used to generate primary T cells expressing antigen-specific chimeric antigen receptors, that is, CAR T cells. The two differently engineered primary T cells are expanded and validated for their respective functions, that is, calibrated synthesis of desired proteins upon engaging the target cells, which is specific for the T-cell biofactory cells, and cytolysis of the target cells common to both types of cells. The process is compliant with current Good Manufacturing Practices and can be used to support the scale-up for clinical translation.


Assuntos
Engenharia Celular , Lentivirus , Cultura Primária de Células , Receptores de Antígenos Quiméricos , Linfócitos T , Transgenes , Humanos , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/citologia , Linfócitos T/metabolismo
13.
Adv Biosyst ; 4(1): e1900224, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32293122

RESUMO

A set of genetically engineered isogenic cell lines is developed to express either folate receptor alpha or mesothelin, and a control cell line negative for both antigens. These cell lines also express fluorescent and bioluminescent reporter transgenes. The cell lines are used to authenticate specificity and function of a T-cell biofactory, a living vector that is developed to express proportionate amounts of engineered proteins upon engaging with disease cells through their specific antigenic biomarkers. The engineered cell lines are also used to assess the cytolytic function and specificity of primary T cells engineered with chimeric antigen receptors; and the specificity of monoclonal antibodies. The strategy described can be used to generate other cell lines to present different disease-specific biomarkers for use as quality control tools.


Assuntos
Engenharia Celular/métodos , Engenharia Genética/métodos , Neoplasias Ovarianas/genética , Receptores de Antígenos Quiméricos/genética , Linfócitos T , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Ovarianas/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/citologia , Linfócitos T/metabolismo
14.
J Adolesc Health ; 66(5): 567-574, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32046896

RESUMO

PURPOSE: The aim of the study was to investigate associations between sleep disturbances and mental health in adolescents. METHODS: Data are from a national sample of 11,670 U.S. participants (5,594 females, aged 9-10 years, 63.5% white) in the Adolescent Brain Cognitive Development study. Initial longitudinal analyses were conducted for a subset of the sample (n = 4,951). Measures of youth sleep disturbance (disorders of initiating and maintaining sleep, sleep-wake transition disorders, and disorders of excessive somnolence) and "typical" total sleep time (number of hours slept on most nights in the past 6 months) were obtained from the parent-report Sleep Disturbance Scale (Data Release 2.0). Parent-report measures of youth mental health (depression, internalizing, and externalizing behaviors) from the Child Behavior Checklist and typical screen time were included. RESULTS: At baseline, greater sleep disturbance and shorter total sleep time were associated with greater internalizing, externalizing, and depression scores. After controlling for baseline mental health symptoms, baseline sleep disturbance significantly predicted depression and internalizing and externalizing scores at 1-year follow-up. A significant interaction with sex indicated that the association between disorders of excessive somnolence and depression 1 year later was steeper for girls, compared with boys (p < .001; 95% confidence interval 1.04-3.45). CONCLUSIONS: Sleep disturbances predicted future mental health, particularly depression in this young sample, highlighting the potential to harness sleep as a tool to mitigate the persistence of depression across early adolescence and potentially prevent an adolescent onset of major depressive disorder.


Assuntos
Transtorno Depressivo Maior , Transtornos do Sono-Vigília , Adolescente , Encéfalo , Criança , Cognição , Depressão/diagnóstico , Depressão/epidemiologia , Feminino , Humanos , Masculino , Sono , Transtornos do Sono-Vigília/epidemiologia
15.
Int J Radiat Biol ; 96(1): 35-46, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30394814

RESUMO

Purpose: There is a need to rapidly triage individuals for absorbed radiation dose following a significant nuclear event. Since most exposed individuals will not have physical dosimeters, we are developing a method to assess exposure dose based on the analysis of a specific panel of blood proteins that can be easily obtained from a fingerstick blood sample.Materials and methods: In three large non-human primate (NHP) studies, animals were exposed to single acute total body doses of x-ray or gamma radiation. A total of 895 blood samples were obtained at baseline and for 7 days after exposure, to evaluate the temporal progression of markers in each of 10 animals (5M/5F) in six dose groups receiving 0-10 Gy. We used tandem mass spectrometry and immunoassay techniques to identify radiation-responsive proteins in blood plasma samples.Results: A blood protein biomarker panel was developed based on analysis of blood plasma samples obtained from several irradiation studies in NHPs that aimed to simulate acute radiation injury in humans from a nuclear exposure event. Panels of several subsets of proteins were shown to accurately classify plasma samples into two exposure groups either above or below a critical dose threshold with sensitivities and specificities exceeding 90%.Conclusion: This study lays the groundwork for developing a radiation biodosimetry triage tool. Our results in NHPs must be compared with those in human patients undergoing radiotherapy to determine if the biomarker panel proteins exhibit a similar radiation response and allow adequate classification power in humans.


Assuntos
Proteínas Sanguíneas/análise , Sistemas Automatizados de Assistência Junto ao Leito , Radiometria/métodos , Animais , Biomarcadores/análise , Testes Hematológicos , Imunoensaio , Macaca mulatta , Fatores de Tempo
16.
Int J Radiat Biol ; 96(1): 145-154, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31021662

RESUMO

Purpose: Rapid depletion of white blood cells, platelets, and reticulocytes are hallmarks of hematopoietic injury of acute radiation syndrome (H-ARS) and, if left untreated, can lead to severe health consequences including death. While the granulocyte colony stimulating factors (G-CSF) filgrastim (Neupogen®), pegfilgrastim (Neulasta®), and sargramostim (Leukine®) are approved to increase survival in patients exposed to a myelosuppressive dose of radiation, no medical countermeasure is currently available for treatment of the thrombocytopenia that also results following radiation exposure. Romiplostim (Nplate®), a thrombopoietin receptor agonist, is the first FDA-approved thrombopoiesis-stimulating protein for the treatment of low platelet (PLT) counts in adults with chronic immune thrombocytopenia. Herein, we present the results of an analysis in mice of romiplostim as a medical countermeasure to improve survival and PLT recovery following acute radiation.Materials and methods: Male and female C57BL/6J mice (11 - 12 weeks of age, n = 21/sex/group) were total body irradiated (TBI) with 6.8 Gy X-rays that reduces 30-day survival to 30% (LD70/30). Vehicle, romiplostim, and/or pegfilgrastim were administered subcutaneously beginning 24 h after TBI for 1-5 days. Evaluation parameters included 30-day survival, pharmacokinetics, and hematology.Results: Full or maximal efficacy with an ∼40% increase in survival was achieved after a single 30 µg/kg dose of romiplostim. No further survival benefit was seen with higher (100 µg/kg) or more frequent dosing (3 or 5 once daily doses at 30 µg/kg) of romiplostim or combined treatment with pegfilgrastim. Pharmacodynamic analysis revealed that the platelet nadir was not as low and recovery was faster in the irradiated mice treated with romiplostim when compared with irradiated control animals (Day 8 versus 10 nadir; Day 22 versus 29 recovery to near baseline). Platelet volume also increased more rapidly after romiplostim injection. Kinetic profiles of other hematology parameters were similar between TBI romiplostim-treated and control mice. Peak serum levels of romiplostim in TBI mice occurred 4 - 24 h (Tmax) after injection with a t1/2 of ∼24 h. Cmax values were at ∼6 ng/ml after 30 µg/kg ± TBI and ∼200 ng/ml after 300 µg/kg. A 10-fold higher romiplostim dose increased the AUClast values by ∼35-fold.Conclusion: A single injection of romiplostim administered 24 h after TBI is a promising radiation medical countermeasure that dramatically increased survival, with or without pegfilgrastim, and hastened PLT recovery in mice.


Assuntos
Plaquetas/efeitos dos fármacos , Plaquetas/efeitos da radiação , Contramedidas Médicas , Proteínas Recombinantes de Fusão/farmacologia , Trombopoetina/farmacologia , Animais , Plaquetas/citologia , Relação Dose-Resposta a Droga , Interações Medicamentosas , Feminino , Filgrastim/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Contagem de Plaquetas , Polietilenoglicóis/farmacologia , Receptores Fc , Proteínas Recombinantes de Fusão/farmacocinética , Análise de Sobrevida , Trombopoetina/farmacocinética , Raios X/efeitos adversos
17.
Ann Behav Med ; 53(12): 1032-1044, 2019 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-31009528

RESUMO

BACKGROUND: Understanding the characteristics of smokers who are successful in quitting may help to increase smoking cessation rates. PURPOSE: To examine heterogeneity in cessation outcome at 6 months following smoking cessation behavioral counseling with or without weight management counseling. METHODS: 2,540 smokers were recruited from a large quitline provider and then randomized to receive proactive smoking cessation behavioral counseling without or with two versions of weight management counseling. A Classification and Regression Tree (CART) analysis was conducted to identify the individual pretreatment and treatment characteristics of groups of smokers with different quitting success (as measured by point prevalence of self-reported smoking of any amount at 6 months). RESULTS: CART analysis identified 10 subgroups ranging from 25.5% to 70.2% abstinent. The splits in the CART tree involved: the total number of counseling and control calls received, whether a smoking cessation pharmacotherapy was used, and baseline measures of cigarettes per day, confidence in quitting, expectation that the study would help the participant quit smoking, the motivation to quit, exercise minutes per week, anxiety, and lack of interest or pleasure in doing things. Costs per quitter ranged from a low of $US270 to a high of $US630. Specific treatment recommendations are made for each group. CONCLUSIONS: These results indicate the presence of a substantial variation in abstinence following treatment, and that the total extent of contact via counseling calls of any type and baseline characteristics, rather than assigned treatment, were most important to subgroup membership and abstinence. Tailored treatments to subgroups who are at high risk for smoking following a quit attempt could increase successful smoking cessation.


Assuntos
Fumar Cigarros/terapia , Aconselhamento/estatística & dados numéricos , Comportamentos Relacionados com a Saúde , Avaliação de Processos e Resultados em Cuidados de Saúde/estatística & dados numéricos , Abandono do Hábito de Fumar/estatística & dados numéricos , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade
18.
Behav Med ; 45(4): 271-281, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-28985151

RESUMO

This study evaluated the feasibility and efficacy of integrating mindfulness training into a phone-based weight loss program to improve outcomes in those with high levels of emotional eating. Participants were 75 enrollees into an employer-sponsored weight loss program who reported high levels of overeating in response to thoughts and feelings. Seventy-five overweight and obese participants (92% female, 65% Caucasian, aged 26 to 68 years) were randomized to the new mindfulness weight loss program (n = 50) or the standard behavioral weight loss program (n = 25). Both programs consisted of 11 coaching calls with health coaches and registered dietitians with supplemental online materials. Satisfaction, engagement, and percent weight lost did not significantly differ for intervention vs. control at six months. Intervention participants had significantly better scores at six-month follow-up on mindful eating, binge eating, experiential avoidance, and one mindfulness subscale. Exploratory analyses showed that improvements on several measures predicted more weight loss in the intervention group. This pilot study found that integrating mindfulness into a brief phone-based behavioral weight loss program was feasible and acceptable to participants, but did not produce greater weight loss on average, despite hypothesized changes in mindful eating. Only one third of intervention participants reported participating in mindfulness exercises regularly. Mechanisms of change observed within the intervention group suggest that for adults with high levels of emotional eating those who embrace mindful eating and meditation may lose more weight with a mindfulness intervention.


Assuntos
Atenção Plena/métodos , Obesidade/psicologia , Programas de Redução de Peso/métodos , Adulto , Idoso , Peso Corporal , Ingestão de Alimentos/psicologia , Emoções , Exercício Físico , Comportamento Alimentar/psicologia , Feminino , Humanos , Masculino , Meditação , Pessoa de Meia-Idade , Sobrepeso/psicologia , Projetos Piloto , Distribuição Aleatória , Telefone , Redução de Peso/fisiologia
19.
IEEE Trans Biomed Eng ; 65(4): 733-744, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28641243

RESUMO

OBJECTIVE: This paper presents a framework for temporal shape analysis to capture the shape and changes of anatomical structures from three-dimensional+t(ime) medical scans. METHOD: We first encode the shape of a structure at each time point with the spectral signature, i.e., the eigenvalues and eigenfunctions of the Laplace operator. We then expand it to capture morphing shapes by tracking the eigenmodes across time according to the similarity of their eigenfunctions. The similarity metric is motivated by the fact that small-shaped deformations lead to minor changes in the eigenfunctions. Following each eigenmode from the beginning to end results in a set of eigenmode curves representing the shape and its changes over time. RESULTS: We apply our encoding to a cardiac dataset consisting of series of segmentations outlining the right and left ventricles over time. We measure the accuracy of our encoding by training classifiers on discriminating healthy adults from patients that received reconstructive surgery for Tetralogy of Fallot (TOF). The classifiers based on our encoding significantly surpass deformation-based encodings of the right ventricle, the structure most impacted by TOF. CONCLUSION: The strength of our framework lies in its simplicity: It only assumes pose invariance within a time series but does not assume point-to-point correspondence across time series or a (statistical or physical) model. In addition, it is easy to implement and only depends on a single parameter, i.e., the number of curves.


Assuntos
Algoritmos , Imageamento Tridimensional/métodos , Imagem Cinética por Ressonância Magnética/métodos , Adulto , Ventrículos do Coração/diagnóstico por imagem , Humanos , Tetralogia de Fallot/diagnóstico por imagem , Tetralogia de Fallot/cirurgia
20.
Nicotine Tob Res ; 18(9): 1837-1844, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27113016

RESUMO

INTRODUCTION: Metabolic enzyme variation and other patient and environmental characteristics influence smoking behaviors, treatment success, and risk of related disease. Population-specific variation in metabolic genes contributes to challenges in developing and optimizing pharmacogenetic interventions. We applied a custom genome-wide genotyping array for addiction research (Smokescreen), to three laboratory-based studies of nicotine metabolism with oral or venous administration of labeled nicotine and cotinine, to model nicotine metabolism in multiple populations. The trans-3'-hydroxycotinine/cotinine ratio, the nicotine metabolite ratio (NMR), was the nicotine metabolism measure analyzed. METHODS: Three hundred twelve individuals of self-identified European, African, and Asian American ancestry were genotyped and included in ancestry-specific genome-wide association scans (GWAS) and a meta-GWAS analysis of the NMR. We modeled natural-log transformed NMR with covariates: principal components of genetic ancestry, age, sex, body mass index, and smoking status. RESULTS: African and Asian American NMRs were statistically significantly (P values ≤ 5E-5) lower than European American NMRs. Meta-GWAS analysis identified 36 genome-wide significant variants over a 43 kilobase pair region at CYP2A6 with minimum P = 2.46E-18 at rs12459249, proximal to CYP2A6. Additional minima were located in intron 4 (rs56113850, P = 6.61E-18) and in the CYP2A6-CYP2A7 intergenic region (rs34226463, P = 1.45E-12). Most (34/36) genome-wide significant variants suggested reduced CYP2A6 activity; functional mechanisms were identified and tested in knowledge-bases. Conditional analysis resulted in intergenic variants of possible interest (P values < 5E-5). CONCLUSIONS: This meta-GWAS of the NMR identifies CYP2A6 variants, replicates the top-ranked single nucleotide polymorphism from a recent Finnish meta-GWAS of the NMR, identifies functional mechanisms, and provides pan-continental population biomarkers for nicotine metabolism. IMPLICATIONS: This multiple ancestry meta-GWAS of the laboratory study-based NMR provides novel evidence and replication for genome-wide association of CYP2A6 single nucleotide and insertion-deletion polymorphisms. We identify three regions of genome-wide significance: proximal, intronic, and distal to CYP2A6. We replicate the top-ranking single nucleotide polymorphism from a recent GWAS of the NMR in Finnish smokers, identify a functional mechanism for this intronic variant from in silico analyses of RNA-seq data that is consistent with CYP2A6 expression measured in postmortem lung and liver, and provide additional support for the intergenic region between CYP2A6 and CYP2A7.


Assuntos
Citocromo P-450 CYP2A6/genética , Nicotina/genética , Nicotina/metabolismo , Fumar/genética , Tabagismo/genética , Adulto , Povo Asiático/genética , População Negra/genética , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , População Branca/genética , Adulto Jovem
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