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1.
Micromachines (Basel) ; 15(4)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38675319

RESUMO

The critical structural parameters are optimized and studied using the numerical simulation method to improve the resolution and stability of the Micro-Thrust Measurement Platform (MTMP). Under two different ground random vibration environments, the parameters, such as pivot thickness, pendulum rod length, and pivot structure, are focused on analyzing the influence of the system's resolution and stability. The results show that when the thickness of the pivot is 0.04 mm or 0.2 mm, and the pendulum rod length is 2 m, the effect of ground random vibration on the MTMP is minimized. At 0.1 mHz, it can reach 0.0057 µN/Hz. In the series double-pivot structure, an appropriate increase in the distance between the sheets can further optimize the above conclusions. The results and analysis within this study can provide support for the engineering design of the MTMP.

2.
J Med Virol ; 95(12): e29300, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38063070

RESUMO

Little is known about antibody responses to natural Omicron infection and the risk factors for poor responders in patients with hematological malignancies (HM). We conducted a multicenter, prospective cohort study during the latest Omicron wave in Chongqing, China, aiming to compare the antibody responses, as assessed by IgG levels of anti-receptor binding domain of spike protein (anti-S-RBD), to Omicron infection in the HM cohort (HMC) with healthy control cohort (HCC), and solid cancer cohort (SCC). In addition, we intend to explore the risk factors for poor responders in the HMC. Among the 466 HM patients in this cohort, the seroconversion rate was 92.7%, no statistically difference compared with HCC (98.2%, p = 0.0513) or SCC (100%, p = 0.1363). The median anti-S-RBD IgG titer was 29.9 ng/mL, significantly lower than that of HCC (46.9 ng/mL, p < 0.0001) or SCC (46.2 ng/mL, p < 0.0001). Risk factors associated with nonseroconversion included no COVID-19 vaccination history (odds ratio [OR] = 4.58, 95% confidence interval [CI]: 1.75-12.00, p = 0.002), clinical course of COVID-19 ≤ 7 days (OR = 2.86, 95% CI: 1.31-6.25, p = 0.008) and severe B-cell reduction (0-10/µL) (OR = 3.22, 95% CI: 1.32-7.88, p = 0.010). Risk factors associated with low anti-S-RBD IgG titer were clinical course of COVID-19 ≤ 7 days (OR = 2.58, 95% CI: 1.59-4.18, p < 0.001) and severe B-cell reduction (0-10/µL) (OR = 2.87, 95% CI: 1.57-5.24, p < 0.001). This study reveals a poor antibody responses to Omicron (BA.5.2.48) infection in HM patients and identified risk factors for poor responders. Highlights that HM patients, especially those with these risk factors, may be susceptible to SARS-CoV-2 reinfection, and the postinfection vaccination strategies for these patients should be tailored. Clinical trial: ChiCTR2300071830.


Assuntos
COVID-19 , Neoplasias Hematológicas , Humanos , Formação de Anticorpos , SARS-CoV-2 , Estudos Prospectivos , Neoplasias Hematológicas/complicações , Progressão da Doença , Imunoglobulina G , Anticorpos Antivirais
3.
Oncol Nurs Forum ; 51(1): 59-69, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38108447

RESUMO

PROBLEM IDENTIFICATION: The risk of venous thromboembolism (VTE) in patients with lymphoma may be overlooked because patients often experience thrombocytopenia from the disease or chemotherapy. A meta-analysis was conducted to identify the prevalence of and risk factors for VTE in patients with lymphoma. LITERATURE SEARCH: A systematic search of Embase®, Web of Science, PubMed®, and Cochrane Library databases was conducted to identify relevant studies investigating VTE in patients with lymphoma. DATA EVALUATION: The methodologic quality of the eligible observational studies was assessed using the Newcastle-Ottawa Scale. Stata, version 12.0, was used to perform the meta-analysis. SYNTHESIS: Female sex, older age, history of VTE, a diagnosis of diffuse large B-cell lymphoma, Ann Arbor stage III-IV disease, a higher performance status score, bulky disease, central nervous system involvement, a white blood cell count greater than 11 × 109/L, a D-dimer level greater than 0.5 mg/L, central venous catheterization, and treatment with doxorubicin were significant risk factors for VTE. IMPLICATIONS FOR PRACTICE: This meta-analysis identified risk factors for VTE, which may provide a theoretical foundation for clinical staff to conduct early assessment and identification of high-risk VTE groups, allowing for timely intervention.


Assuntos
Linfoma , Tromboembolia Venosa , Humanos , Feminino , Tromboembolia Venosa/induzido quimicamente , Tromboembolia Venosa/epidemiologia , Prevalência , Linfoma/tratamento farmacológico , Pacientes , Fatores de Risco
4.
Front Nutr ; 9: 1050139, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438738

RESUMO

Objective: To investigate the predictive value of nutritional status on the prognosis of patients with human immunodeficiency virus (HIV) infection-related lymphoma. Materials and methods: A total of 149 patients with HIV infection-related lymphoma who were admitted to our hospital from August 2012 to May 2022 were selected as research subjects. Based on the patient prognosis, they were divided into a poor prognosis group (n = 30) and a good prognosis group (n = 119). General data from patients in both groups were collected, and the nutritional status of the patients was evaluated using the Controlling Nutritional Status (CONUT) score. Factors affecting the prognosis of HIV infection-related lymphoma were analyzed using univariate and multivariate analyses, and a prediction model was developed based on the analyzed factors. The receiver operating characteristic (ROC) curve was used to analyze the prediction model of the CONUT score alone and included the CONUT score in the prognosis of patients with HIV infection-related lymphoma. The predictive value of the data was assessed, and a survival curve was drawn to compare the survival of patients with different nutritional statuses. Results: There were significant differences in age, B symptoms, treatment conditions, International Prognostic Index (IPI), pathological stage, Eastern Collaborative Tumor Group physical status score (ECOG PS), CD4+ cell count, ß2 microglobulin, and lactate dehydrogenase (LDH) between the poor prognosis group and the good prognosis group (p < 0.05). The CONUT score of the poor prognosis group was higher than that of the good prognosis group, and the difference was statistically significant (p < 0.05). A univariate analysis demonstrated that the age, B symptoms, treatment status, IPI, pathological stage, ECOG PS, CD4+ cell count, ß2 microglobulin, LDH, and CONUT score were prognostic factors for patients with HIV infection-related lymphoma (p < 0.05). The results of a multivariate regression analysis demonstrated that the age, B symptoms, treatment status, IPI, pathological stage, ECOG PS, and CONUT score were independent risk factors for the prognosis of patients with HIV infection-related lymphoma (p < 0.05). The prediction model was constructed according to the multivariate Cox regression analysis results. The model formula was as follows: Logit(p) = -10.687 + 1.728 × age + 1.713 × B symptoms + 1.682 × treatment status + 1.810 × IPI + 1.643 × pathological stage + 1.584 × ECOG PS + 1.779 × CONUT score. The ROC curve was used to analyze the predictive value of the CONUT score alone and the predictive model including the CONUT score on the prognosis of patients with HIV infection-related lymphoma. The predictive value of the prognosis of patients with tumors was higher (p < 0.05). According to the results of the ROC curve analysis, the patients were divided into a high CONUT group (CONUT > 6.00 points, n = 31) and a low CONUT group (CONUT ≤ 6.00 points, n = 118) based on the Optimum threshold of the CONUT score. The survival curve showed that the survival rate of the high CONUT group was lower than that of the low CONUT group (p < 0.05). Conclusion: The poor prognosis of HIV infection-related lymphoma is related to nutritional status, which is an independent risk factor affecting the prognosis of patients and can be used as a practical indicator to predict the prognosis of patients.

5.
Theranostics ; 11(10): 4699-4709, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33754022

RESUMO

Rationale: The onset of cytokine release syndrome (CRS) and in vivo persistence of anti-CD19 chimeric antigen receptor T (CAR-T) cells after infusion correlate with clinical responsiveness. However, there are no known baseline biomarkers that can predict the prognosis of patients with B-lineage non-Hodgkin lymphoma (B-NHL). The aim of this study was to identify blood cell populations associated with beneficial outcomes in B-NHL patients administered CAR-T cell immunotherapies. Methods: We enumerated peripheral blood and CAR-T cells by retrospectively analyzing three CAR-T cell trials involving 65 B-NHL patients. We used a preclinical model to elucidate the eosinophil mechanism in CAR-T cell therapy. Results: During an observation period up to 30 mo, B-NHL patients with higher baseline eosinophil counts had higher objective response rates than those with low eosinophil counts. Higher baseline eosinophil counts were also significantly associated with durable progression-free survival (PFS). The predictive significance of baseline eosinophil counts was validated in two independent cohorts. A preclinical model showed that eosinophil depletion impairs the intratumoral infiltration of transferred CAR-T cells and reduces CAR-T cell antitumor efficacy. Conclusion: The results of this study suggest that peripheral eosinophils could serve as stratification biomarkers and a recruitment machinery to facilitate anti-CD19 CAR-T cell therapy in B-NHL patients.


Assuntos
Eosinófilos , Imunoterapia Adotiva , Linfoma de Células B/terapia , Receptores de Antígenos Quiméricos , Adulto , Idoso , Animais , Antígenos CD19 , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Humanos , Contagem de Leucócitos , Linfoma de Células B/sangue , Masculino , Camundongos , Pessoa de Meia-Idade , Prognóstico , Intervalo Livre de Progressão , Adulto Jovem
6.
J Vis Exp ; (144)2019 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-30829319

RESUMO

Miniaturized spacecraft and satellites require smart, highly efficient and durable low-thrust thrusters, capable of extended, reliable operation without attendance and adjustment. Thermochemical thrusters which utilize thermodynamic properties of gases as a means of acceleration have physical limitations on their exhaust gas velocity, resulting in low efficiency. Moreover, these engines demonstrate extremely low efficiency at small thrusts and may be unsuitable for continuously operating systems which provide real-time adaptive control of the spacecraft orientation, velocity and position. In contrast, electric propulsion systems which use electromagnetic fields to accelerate ionized gases (i.e., plasmas) do not have any physical limitation in terms of exhaust velocity, allowing virtually any mass efficiency and specific impulse. Low-thrust Hall thrusters have a lifetime of several thousand hours. Their discharge voltage ranges between 100 and 300 V, operating at a nominal power of <1 kW. They vary from 20 to 100 mm in size. Large Hall thrusters can provide fractions of millinewton of thrust. Over the past few decades, there has been an increasing interest in small mass, low power, and high efficiency propulsion systems to drive satellites of 50-200 kg. In this work, we will demonstrate how to build, test, and optimize a small (30 mm) Hall thruster capable of propelling a small satellite weighing about 50 kg. We will show the thruster operating in a large space environment simulator, and describe how thrust is measured and electric parameters, including plasma characteristics, are collected and processed to assess key thruster parameters. We will also demonstrate how the thruster is optimized to make it one of the most efficient small thrusters ever built. We will also address challenges and opportunities presented by new thruster materials.


Assuntos
Miniaturização/instrumentação , Astronave/instrumentação , Aceleração , Desenho de Equipamento , Gases/química , Temperatura , Emissões de Veículos
7.
Inorg Chem ; 50(10): 4412-6, 2011 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-21488667

RESUMO

A series of compact La/O-vacant La(1-x)CoO(3-y) compounds were prepared by a cold high-pressure procedure, and their thermoelectric (TE) properties were investigated. Compared with the ion-substituted hole-type LaCoO(3) systems (e.g., La(1-x)Sr(x)CoO(3)), the thermal conduction of La(1-x)CoO(3-y) is noticeably reduced by the La/O vacancies, whereas the electric transport is less influenced, which results in an efficient ZT enhancement. We demonstrate that the large thermal conductivity reduction originates from the strong point-defect scattering, and La(1-x)CoO(3-y) can be rationalized as a partially filled solid solution: La(1-x)◻(x)CoO(3-y)◻(y), where ◻ denotes a vacancy. Such intrinsic thermal conductivity suppression provides an effective pathway for the design of better TE materials.

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