Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
1.
HPB (Oxford) ; 26(7): 938-948, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38705793

RESUMO

BACKGROUND: Intrahepatic cholangiocarcinoma (iCCA) is the second most common hepatic malignancy and has a poor prognosis. Surgical resection is the standard of care for patients with resectable disease, representing 30-40% of cases. Increasingly, neoadjuvant systemic therapy is being utilized in patients due to high-risk anatomic or biologic considerations. However, data on the clinical effect of this approach are limited. We performed a cohort study to evaluate the effect of neoadjuvant therapy in patients with oncologically high-risk iCCA. METHODS: iCCA patients (n = 181) between the years 2014-2020 were reviewed for clinical, histopathologic, treatment, and outcome-related data. Tumor regression grade was scored per CAP criteria for gastrointestinal carcinomas. RESULTS: 47 iCCA patients received neoadjuvant therapy and 72 did not. Neoadjuvant treatment led to objective response and tumor regression by CAP score. After adjustment for age, clinical stage, and tumor size, the outcomes of patients who had neoadjuvant therapy followed by surgery were not significantly different from those patients who had surgery first. DISCUSSION: In conclusion, neoadjuvant therapy in iCCA facilitated surgical care. The progression-free and overall survival for surgical patients with and without neoadjuvant therapy were not significantly different suggesting this approach needs further exploration as an effective treatment paradigm.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Terapia Neoadjuvante , Humanos , Colangiocarcinoma/terapia , Colangiocarcinoma/mortalidade , Colangiocarcinoma/patologia , Colangiocarcinoma/cirurgia , Neoplasias dos Ductos Biliares/terapia , Neoplasias dos Ductos Biliares/patologia , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/cirurgia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Hepatectomia , Resultado do Tratamento
2.
HPB (Oxford) ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789383

RESUMO

The Publisher regrets that this article is an accidental duplication of an article that has already been published, https://doi.org/10.1016/j.hpb.2024.04.011. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/policies/article-withdrawal.

3.
J Infect Dis ; 228(10): 1367-1374, 2023 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-37141390

RESUMO

BACKGROUND: Protection against herpes zoster is primarily conferred by cell-mediated immunity. However, anti-varicella-zoster virus (VZV) glycoprotein (anti-gp) antibody responses to zoster vaccine live (ZVL) are correlated with protection, suggesting a potential protective role for antibody. Detailed studies of antibody responses to the recombinant zoster vaccine (RZV) are provided. METHODS: We compared enzyme-linked immunosorbent assay-measured anti-VZV glycoproteins (anti-gp) and glycoprotein E (anti-gE) antibody levels and avidity in 159 participants randomized to RZV (n = 80) or ZVL (n = 79) recipients over 5 years after vaccination and identified predictors of antibody persistence. RESULTS: The comparison between vaccine groups showed higher anti-gE and anti-gp antibody levels after RZV than after ZVL over the 5-year study duration. RZV recipients also had higher anti-gE avidity for 5 years and higher anti-gp avidity in the first year after vaccination. Compared with prevaccination levels, RZV recipients maintained higher levels of anti-gE antibodies and avidity for 5 years, whereas ZVL recipients only maintained higher anti-gE avidity. Anti-gp antibody levels and avidity decreased to prevaccination levels or below beyond 1 year after vaccination in both groups. Independent predictors of persistence of antibody levels and avidity included vaccine type, prevaccination and peak antibody levels and avidity, prevaccination and peak cell-mediated immunity, and age. Sex or prior ZVL administration did not affect persistence. CONCLUSIONS: Antibody responses and avidity were higher and more persistent in RZV than in ZVL recipients. The effect of age on antibody persistence in RZV recipients is novel.


Assuntos
Vacina contra Herpes Zoster , Herpes Zoster , Humanos , Formação de Anticorpos , Herpes Zoster/prevenção & controle , Herpesvirus Humano 3 , Glicoproteínas , Vacinas Sintéticas
4.
Comput Methods Appl Mech Eng ; 417(Pt B)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38249440

RESUMO

The glymphatic system is a brain-wide system of perivascular networks that facilitate exchange of cerebrospinal fluid (CSF) and interstitial fluid (ISF) to remove waste products from the brain. A greater understanding of the mechanisms for glymphatic transport may provide insight into how amyloid beta (Aß) and tau agglomerates, key biomarkers for Alzheimer's disease and other neurodegenerative diseases, accumulate and drive disease progression. In this study, we develop an image-guided computational model to describe glymphatic transport and Aß deposition throughout the brain. Aß transport and deposition are modeled using an advection-diffusion equation coupled with an irreversible amyloid accumulation (damage) model. We use immersed isogeometric analysis, stabilized using the streamline upwind Petrov-Galerkin (SUPG) method, where the transport model is constructed using parameters inferred from brain imaging data resulting in a subject-specific model that accounts for anatomical geometry and heterogeneous material properties. Both short-term (30-min) and long-term (12-month) 3D simulations of soluble amyloid transport within a mouse brain model were constructed from diffusion weighted magnetic resonance imaging (DW-MRI) data. In addition to matching short-term patterns of tracer deposition, we found that transport parameters such as CSF flow velocity play a large role in amyloid plaque deposition. The computational tools developed in this work will facilitate investigation of various hypotheses related to glymphatic transport and fundamentally advance our understanding of its role in neurodegeneration, which is crucial for the development of preventive and therapeutic interventions.

5.
J Infect Dis ; 225(8): 1477-1481, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-34850039

RESUMO

We compared glycoprotein E (gE)- and varicella zoster virus (VZV)-specific Th1 immunity in 160 adults, aged 50-85 years, randomized to receive live or recombinant zoster vaccine (RZV). gE-specific responses measured by interferon-γ (IFN-γ) and interleukin 2 (IL-2) dual-color Fluorospot were significantly higher at all time points postimmunization in RZV recipients. VZV-specific IL-2+ memory, but not IFN-γ+ or IFN-γ+IL-2+ effector responses, were higher in RZV recipients at ≥3 months postimmunization. Only RZV recipients maintained higher postvaccination gE-specific IL-2+ and IFN-γ+ and VZV-specific IL-2+ responses for 5 years. The 5-year persistence of VZV-specific memory and gE-specific Th1 immunity may underlie superior RZV efficacy. Clinical Trials Registration NCT02114333.


Assuntos
Vacina contra Herpes Zoster , Herpes Zoster , Idoso , Idoso de 80 Anos ou mais , Herpes Zoster/prevenção & controle , Herpesvirus Humano 3 , Humanos , Imunidade Celular , Interferon gama , Interleucina-2 , Pessoa de Meia-Idade , Vacinas Sintéticas
6.
Clin Infect Dis ; 75(6): 996-1005, 2022 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-35037049

RESUMO

BACKGROUND: The effect of pneumococcal vaccination of mothers with human immunodeficiency virus (HIV) on infant responses to childhood vaccination has not been studied. We compared the immunogenicity of 10-valent pneumococcus conjugate vaccine (PCV-10) in HIV-exposed uninfected infants born to mothers who received PCV-10, 23-valent pneumococcus polysaccharide vaccine (PPV-23), or placebo during pregnancy. METHODS: Antibody levels against 7 serotypes were measured at birth, before the first and second doses of PCV-10m and after completion of the 2-dose regimen in 347 infants, including 112 born to mothers who received PPV-23, 112 who received PCV-10, and 119 who received placebo during pregnancy. Seroprotection was defined by antibody levels ≥0.35 µg/mL. RESULTS: At birth and at 8 weeks of life, antibody levels were similar in infants born to PCV-10 or PPV-23 recipients and higher than in those born to placebo recipient. After the last dose of PCV-10, infants in the maternal PCV-10 group had significantly lower antibody levels against 5 serotypes than those in the maternal PPV-23 group and against 3 serotypes than those in the maternal placebo group, and they did not have higher antibody levels against any serotype. The seroprotection rate against 7 serotypes was 50% in infants in the maternal PCV-10 group, compared with 71% in both of the maternal PPV-23 and placebo groups (P < .001). CONCLUSIONS: Administration of PCV-10 during pregnancy was associated with decreased antibody responses to PCV-10 and seroprotection rates in infants. Considering that PCV-10 and PPV-23 had similar immunogenicity in pregnant women with HIV and that administration of PPV-23 did not affect the immunogenicity of PCV-10 in infants, PPV-23 in pregnancy may be preferred over PCV-10.


Assuntos
Infecções por HIV , Infecções Pneumocócicas , Anticorpos Antibacterianos/uso terapêutico , Feminino , HIV , Infecções por HIV/tratamento farmacológico , Humanos , Lactente , Recém-Nascido , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas , Polissacarídeos , Gravidez , Streptococcus pneumoniae , Vacinação , Vacinas Conjugadas
7.
Nat Mater ; 20(12): 1683-1688, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34294884

RESUMO

Superionic conductors possess liquid-like ionic diffusivity in the solid state, finding wide applicability from electrolytes in energy storage to materials for thermoelectric energy conversion. Type I superionic conductors (for example, AgI, Ag2Se and so on) are defined by a first-order transition to the superionic state and have so far been found exclusively in three-dimensional crystal structures. Here, we reveal a two-dimensional type I superionic conductor, α-KAg3Se2, by scattering techniques and complementary simulations. Quasi-elastic neutron scattering and ab initio molecular dynamics simulations confirm that the superionic Ag+ ions are confined to subnanometre sheets, with the simulated local structure validated by experimental X-ray powder pair-distribution-function analysis. Finally, we demonstrate that the phase transition temperature can be controlled by chemical substitution of the alkali metal ions that compose the immobile charge-balancing layers. Our work thus extends the known classes of superionic conductors and will facilitate the design of new materials with tailored ionic conductivities and phase transitions.

8.
Am J Hematol ; 97(1): 90-98, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34699616

RESUMO

Monoclonal B-cell lymphocytosis (MBL) and chronic lymphocytic leukemia (CLL) are clonal B-cell disorders associated with an increased risk of infections and impaired vaccination responses. We investigated the immunogenicity of recombinant zoster vaccine (RZV) in these patients. Individuals with MBL/untreated CLL and Bruton tyrosine kinase inhibitor (BTKi)-treated CLL patients were given two doses of RZV separated by 2 months. Responses assessed at 3 and 12 months from the first dose of RZV by an anti-glycoprotein E ELISA antibody assay and by dual-color Interferon-γ and Interleukin-2FLUOROSPOT assays were compared to historic controls matched by age and sex. About 62 patients (37 MBL/untreated CLL and 25 BTKi-treated CLL) were enrolled with a median age of 68 years at vaccination. An antibody response at 3 months was seen in 45% of participants, which was significantly lower compared to historic controls (63%, p = .03). The antibody response did not significantly differ between MBL/untreated CLL and BTKi-treated CLL (51% vs. 36%, respectively, p = .23). The CD4+ T-cell response to vaccination was significantly lower in study participants compared to controls (54% vs. 96%, p < .001), mainly due to lower responses among BTKi-treated patients compared to untreated MBL/CLL (32% vs. 73%, p = .008). Overall, only 29% of participants achieved combined antibody and cellular responses to RZV. Among participants with response assessment at 12 months (n = 47), 24% had antibody titers below the response threshold. Hypogammaglobulinemia and BTKi therapy were associated with reduced T-cell responses in a univariate analysis. Strategies to improve vaccine response to RZV among MBL/CLL patients are needed.


Assuntos
Vacina contra Herpes Zoster/uso terapêutico , Herpes Zoster/prevenção & controle , Imunidade Celular , Imunidade Humoral , Leucemia Linfocítica Crônica de Células B/complicações , Linfocitose/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos B/imunologia , Feminino , Herpes Zoster/imunologia , Humanos , Leucemia Linfocítica Crônica de Células B/imunologia , Linfocitose/imunologia , Masculino , Pessoa de Meia-Idade
9.
J Virol ; 93(15)2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31092579

RESUMO

Older age is associated with increased infectious morbidity and decreased immune responses to vaccines, but the mechanisms that mediate this effect are incompletely understood. The efficacy and immunogenicity of the live attenuated zoster vaccine (ZVL) have a very-well-described negative association with the age of the vaccinee. In a study of 600 ZVL recipients 50 to >80 years of age, we investigated immunological factors that might explain the effect of age on the immunogenicity of ZVL. Using FluoroSpot assays and flow cytometry, we determined that varicella-zoster virus (VZV)-specific peak T helper 1 (VZV-Th1) responses to ZVL were independently predicted by prevaccination VZV-Th1 responses, regulatory T cells (Treg), and PD1-expressing immune checkpoint T cells (Tcheck) but not by the age of the vaccinee. Persistence of VZV-Th1 1 year after vaccination was independently predicted by the factors mentioned above, by peak VZV-Th1 responses to ZVL, and by the age of the vaccinee. We further demonstrated by ex vivo blocking experiments the mechanistic role of PD1 and CTLA4 as modulators of decreased VZV-Th1 responses in the study participants. VZV-specific cytotoxic T cell (VZV-CTL) and T follicular helper responses to ZVL did not correlate with age, but similar to other Th1 responses, VZV-CTL peak and baseline responses were independently correlated. These data expand our understanding of the factors affecting the magnitude and kinetics of T cell responses to ZVL in older adults and show the importance of prevaccination Treg and Tcheck in modulating the immunogenicity of ZVL. This presents new potential interventions to increase vaccine responses in older adults.IMPORTANCE Vaccination is the most effective method to protect older adults against viral infections. However, the immunogenicity of viral vaccines in older adults is notoriously poor. The live attenuated zoster vaccine (ZVL) provides the best example of a gradual decrease of vaccine immunogenicity with every 10-year age increase above 50 years. Here we show that the abundance of regulatory T cells before vaccine administration to older adults has a significant inhibitory effect on immune responses to ZVL and, together with baseline immunity to varicella-zoster virus, explains the effect of age on the immunogenicity of ZVL. Moreover, in vitro blockade of regulatory T cell mechanisms of action with biologic modulators restores immune responses to varicella-zoster virus in vaccinees. Collectively, these observations suggest that immune modulators that block regulatory T cell activity may increase responses to viral attenuated vaccines in older adults.


Assuntos
Vacina contra Herpes Zoster/imunologia , Herpes Zoster/prevenção & controle , Herpesvirus Humano 3/imunologia , Imunidade Celular , Subpopulações de Linfócitos T/imunologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Vacina contra Herpes Zoster/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia
10.
J Infect Dis ; 219(2): 335-338, 2019 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-30165651

RESUMO

Protection against zoster conferred by zoster vaccine live (ZVL; Zostavax) wanes over time. We compared varicella-zoster virus cell-mediated immunity (VZV-CMI) of adults ≥70 years who received a second dose of ZVL ≥10 years after the initial dose with de novo-immunized age-matched controls. Before and during the first year after vaccination, VZV-CMI was significantly higher in reimmunized compared with de novo vaccinees. At 3 years, VZV-CMI differences between groups decreased and only memory responses remained marginally higher in reimmunized participants. In conclusion, the increase in VZV-CMI generated by reimmunization with ZVL is at least equally persistent compared with de novo immunization.


Assuntos
Vacina contra Herpes Zoster/administração & dosagem , Vacina contra Herpes Zoster/imunologia , Herpesvirus Humano 3/imunologia , Imunidade Celular/imunologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Feminino , Humanos , Memória Imunológica , Interferon gama/imunologia , Interleucina-2/imunologia , Masculino , Vacinação , Vacinas Atenuadas/imunologia
11.
J Infect Dis ; 218(suppl_2): S81-S87, 2018 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-30247596

RESUMO

Background: Live attenuated (ZV) and recombinant adjuvanted (HZ/su) zoster vaccines differ with respect to efficacy, effect of age, and persistence of protection. We compared cell-mediated immunity (CMI responses to ZV and HZ/su. Methods: This was a randomized, double-blind, placebo-controlled trial stratified by age (50-59 and 70-85 years) and by HZ vaccination status (received ZV ≥5 years before entry or not). Varicella zoster virus (VZV)- and glycoprotein E (gE)-specific CMI were analyzed by interleukin 2 (IL-2) and interferon gamma (IFN-γ) FluoroSpot and flow cytometry at study days 0, 30, 90, and 365. Results: Responses to ZV peaked on day 30 and to HZ/su (administered in 2 doses separated by 60 days) peaked on day 90. Age and vaccination status did not affect peak responses, but higher baseline CMI correlated with higher peak responses. HZ/su generated significantly higher VZV-specific IL-2+ and gE-specific IL-2+, IFN-γ+, and IL-2+/IFN-γ+ peak and 1-year baseline-adjusted responses compared with ZV. VZV-specific IFN-γ+ and IL-2+/IFN-γ+ did not differ between vaccines. HZ/su generated higher memory and effector-memory CD4+ peak responses and ZV generated higher effector CD4+ responses . Conclusions: The higher IL-2 and other memory responses generated by HZ/su compared with ZV may contribute to its superior efficacy. Clinical Trials Registration: NCT02114333.


Assuntos
Vacina contra Herpes Zoster/imunologia , Herpes Zoster/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Citocinas/genética , Citocinas/metabolismo , Método Duplo-Cego , Feminino , Humanos , Interferon gama/metabolismo , Interleucina-2/metabolismo , Masculino , Pessoa de Meia-Idade , Linfócitos T/classificação , Linfócitos T/fisiologia
12.
J Infect Dis ; 213(1): 14-22, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26452397

RESUMO

BACKGROUND: Herpes zoster vaccine (ZV) was administered as a second dose to 200 participants ≥ 70 years old who had received a dose of ZV ≥ 10 years previously (NCT01245751). METHODS: Varicella zoster virus (VZV) antibody titers (measured by a VZV glycoprotein-based enzyme-linked immunosorbent assay [gpELISA]) and levels of interferon γ (IFN-γ) and interleukin 2 (IL-2; markers of VZV-specific cell-mediated immunity [CMI], measured by means of ELISPOT analysis) in individuals aged ≥ 70 years who received a booster dose of ZV were compared to responses of 100 participants aged 50-59 years, 100 aged 60-69 years, and 200 aged ≥ 70 years who received their first dose of ZV. The study was powered to demonstrate noninferiority of the VZV antibody response at 6 weeks in the booster-dose group, compared with the age-matched first-dose group. RESULTS: Antibody responses were similar at baseline and after vaccination across all age and treatment groups. Both baseline and postvaccination VZV-specific CMI were lower in the older age groups. Peak gpELISA titers and their fold rise from baseline generally correlated with higher baseline and postvaccination VZV-specific CMI. IFN-γ and IL-2 results for subjects ≥ 70 years old were significantly higher at baseline and after vaccination in the booster-dose group, compared with the first-dose group, indicating that a residual effect of ZV on VZV-specific CMI persisted for ≥ 10 years and was enhanced by the booster dose. CONCLUSIONS: These findings support further investigation of ZV administration in early versus later age and of booster doses for elderly individuals at an appropriate interval after initial immunization against HZ. CLINICAL TRIALS REGISTRATION: NCT01245751.


Assuntos
Anticorpos Antivirais/imunologia , Vacina contra Herpes Zoster/imunologia , Herpesvirus Humano 3/imunologia , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Feminino , Seguimentos , Herpes Zoster/imunologia , Herpes Zoster/prevenção & controle , Humanos , Imunidade Celular/imunologia , Imunização Secundária , Masculino , Pessoa de Meia-Idade
13.
J Clin Nurs ; 25(23-24): 3628-3642, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27240268

RESUMO

AIMS AND OBJECTIVES: The purposes of this study were to measure the prevalence of, and identify factors associated with, cervical cancer screening among a sample of lesbian, bisexual and queer women, and transgender men. BACKGROUND: Past research has found that lesbian, bisexual and queer women underuse cervical screening service. Because deficient screening remains the most significant risk factor for cervical cancer, it is essential to understand the differences between routine and nonroutine screeners. DESIGN: A convergent-parallel mixed methods design. METHODS: A convenience sample of 21- to 65-year-old lesbian and bisexual women and transgender men were recruited in the USA from August-December 2014. Quantitative data were collected via a 48-item Internet questionnaire (N = 226), and qualitative data were collected through in-depth telephone interviews (N = 20) and open-ended questions on the Internet questionnaire. RESULTS: Seventy-three per cent of the sample was routine cervical screeners. The results showed that a constellation of factors influence the use of cervical cancer screening among lesbian, bisexual and queer women. Some of those factors overlap with the general female population, whereas others are specific to the lesbian, bisexual or queer identity. Routine screeners reported feeling more welcome in the health care setting, while nonroutine screeners reported more discrimination related to their sexual orientation and gender expression. Routine screeners were also more likely to 'out' to their provider. The quantitative and qualitative factors were also compared and contrasted. CONCLUSIONS: Many of the factors identified in this study to influence cervical cancer screening relate to the health care environment and to interactions between the patient and provider. RELEVANCE TO CLINICAL PRACTICE: Nurses should be involved with creating welcoming environments for lesbian, bisexual and queer women and their partners. Moreover, nurses play a large role in patient education and should promote self-care behaviours among lesbian women and transgender men.


Assuntos
Bissexualidade/psicologia , Detecção Precoce de Câncer , Homossexualidade Feminina/psicologia , Minorias Sexuais e de Gênero/psicologia , Transexualidade/psicologia , Neoplasias do Colo do Útero/diagnóstico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Autocuidado , Inquéritos e Questionários , Neoplasias do Colo do Útero/prevenção & controle , Neoplasias do Colo do Útero/psicologia , Adulto Jovem
14.
J Adv Nurs ; 70(3): 523-32, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23869967

RESUMO

AIM: To present the findings of a dimensional analysis of isolation in the context, and from the perspective, of lesbian, gay, bisexual and transgender youth. BACKGROUND: Lesbian, gay, bisexual and transgender youth are often at greater risk for negative health outcomes compared with heterosexual youth. Isolation is one risk factor cited throughout the literature; however, the concept is complicated and has many uses and thus warrants clarification. DESIGN: Concept Analysis. DATA SOURCES: Sources comprise 35 English language research articles retrieved from CINAHL and EBSCOHost (1987-2012). METHODS: A dimensional concept analysis was undertaken to analyse how the concept, isolation, is socially constructed. RESULTS: This dimensional analysis revealed five socially constructed dimensions and four sub-dimensions. These findings indicate that there is substantial variability in the concept of isolation. These differences and variations are most notably observed in the 20 articles (57%) that had more than one dimension. Although some of these articles were explicit with the different meanings and use of the concept, most of the papers had wide variability in the use and meaning of the concept. CONCLUSION: The disproportionately greater physical and mental health disparities between lesbian, gay, bisexual and transgender and heterosexual youth are a signal to conduct more research to clarify the concept of isolation, to develop instrumentation to identify at-risk youth and to explore predictors and consequences of isolation. Nurses and others can lead the way in translating this knowledge into strategies that will improve the health and lives of these young people.


Assuntos
Bissexualidade , Homossexualidade Feminina , Homossexualidade Masculina , Isolamento Social , Transexualidade , Adolescente , Cognição , Emoções , Feminino , Humanos , Masculino
15.
Artigo em Inglês | MEDLINE | ID: mdl-38532042

RESUMO

The vast majority of heart attacks occur when vulnerable plaques rupture, releasing their lipid content into the blood stream leading to thrombus formation and blockage of a coronary artery. Detection of these unstable plaques before they rupture remains a challenge. Hemodynamic features including wall shear stress (WSS) and wall shear stress gradient (WSSG) near the vulnerable plaque and local inflammation are known to affect plaque instability. In this work, a computational workflow has been developed to enable a comprehensive parametric study detailing the effects of 3D plaque shape on local hemodynamics and their implications for plaque instability. Parameterized geometric 3D plaque models are created within a patient-specific coronary artery tree using a NURBS (non-uniform rational B-splines)-based vascular modeling pipeline. Realistic blood flow features are simulated by using a Navier-Stokes solver within an isogeometric finite-element analysis framework. Near wall hemodynamic quantities such as WSS and WSSG are quantified, and vascular distribution of an inflammatory marker (VCAM-1) is estimated. Results show that proximally skewed eccentric plaques have the most vulnerable combination of high WSS and high positive spatial WSSG, and the presence of multiple lesions increases risk of rupture. The computational tool developed in this work, in conjunction with clinical data, -could help identify surrogate markers of plaque instability, potentially leading to a noninvasive clinical procedure for the detection of vulnerable plaques before rupture.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38598420

RESUMO

High-energy-density lithium sulfur (Li-S) batteries suffer heavily from the polysulfide shuttle effect, a result of the dissolution and transport of intermediate polysulfides from the cathode, into the electrolyte, and onto the anode, leading to rapid cell degradation. If this primary mechanism of cell failure is to be overcome, the distribution, dynamics, and degree of polysulfide transport must first be understood in depth. In this work, operando optical fluorescence microscope imaging of optically accessible Li-S cells is shown to enable real-time qualitative visualization of the spatial distribution of lithium polysulfides, both within the electrolyte and porous cathode. Quantitative determinations of spatial concentration are also possible at a low enough concentration. The distribution throughout cycling is monitored, including direct observation of polysulfide shuttling to the anode and consequent dendrite formation. This was enabled through the optimization of a selective fluorescent dye, verified to fluoresce proportionally with concentration of polysulfides within Li-S cells. This ability to directly and conveniently track the spatial distribution of soluble polysulfide intermediates in Li-S battery electrolytes, while the cell operates, has the potential to have a widespread impact across the field, for example, by enabling the influence of a variety of polysulfide mitigation strategies to be assessed and optimized, including in this work the LiNO3 additive.

17.
J Clin Invest ; 133(23)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37788096

RESUMO

Herpes zoster (HZ) is a substantial problem for people with decreased cell-mediated immunity, including older adults. The first vaccine approved for HZ prevention, the zoster vaccine live (ZVL), which provided limited and short-lived protection, has been supplanted by the superior recombinant zoster vaccine (RZV), which provides robust and durable protection. To understand the mechanisms underlying the differential immunologic characteristics of the 2 vaccines, we used T cell receptor ß chain sequencing and peptide-MHC class II tetramer staining to analyze recombinant glycoprotein E-specific (gE-specific) CD4+ T cell clonotypes in RZV and ZVL recipients. Compared with ZVL, RZV expanded more gE-specific CD4+ clonotypes, with greater breadth and higher frequency of public clonotypes. RZV recruited a higher proportion of clonotypes from naive than from memory cells, while ZVL recruited equally from memory and naive compartments. Compared with memory-derived, naive-derived clonotypes were more likely to last 5 or more years after immunization. Moreover, the frequency of tetramer+ persistent clones correlated with the frequency of tetramer+ naive CD4+ prevaccination T cells. We conclude that the ability of RZV to recruit naive CD4+ T cells into the response may contribute to the durability of its effect. The abundance, breadth, and frequency of public clonotypes may further add to its protective effect.


Assuntos
Vacina contra Herpes Zoster , Herpes Zoster , Humanos , Idoso , Linfócitos T CD4-Positivos , Herpesvirus Humano 3 , Vacinação , Vacinas Sintéticas
18.
ACS Nano ; 17(15): 14253-14282, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37459320

RESUMO

The coupled interactions among the fundamental carriers of charge, heat, and electromagnetic fields at interfaces and boundaries give rise to energetic processes that enable a wide array of technologies. The energy transduction among these coupled carriers results in thermal dissipation at these surfaces, often quantified by the thermal boundary resistance, thus driving the functionalities of the modern nanotechnologies that are continuing to provide transformational benefits in computing, communication, health care, clean energy, power recycling, sensing, and manufacturing, to name a few. It is the purpose of this Review to summarize recent works that have been reported on ultrafast and nanoscale energy transduction and heat transfer mechanisms across interfaces when different thermal carriers couple near or across interfaces. We review coupled heat transfer mechanisms at interfaces of solids, liquids, gasses, and plasmas that drive the resulting interfacial heat transfer and temperature gradients due to energy and momentum coupling among various combinations of electrons, vibrons, photons, polaritons (plasmon polaritons and phonon polaritons), and molecules. These interfacial thermal transport processes with coupled energy carriers involve relatively recent research, and thus, several opportunities exist to further develop these nascent fields, which we comment on throughout the course of this Review.

19.
Open Forum Infect Dis ; 10(12): ofad608, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38107018

RESUMO

Background: There is little information on cell-mediated immunity (CMI) to COVID-19 mRNA vaccines in children. We studied adaptive and innate CMI in vaccinated children aged 6 to 60 months. Methods: Blood obtained from participants in a randomized placebo-controlled trial of an mRNA vaccine before and 1 month after the first dose was used for antibody measurements and CMI (flow cytometry). Results: We enrolled 29 children with a mean age of 28.5 months (SD, 15.7). Antibody studies revealed that 10 participants were infected with SARS-CoV-2 prevaccination. Ex vivo stimulation of peripheral blood mononuclear cells with SARS-CoV-2 spike peptides showed significant increases pre- to postimmunization of activated conventional CD4+ and γδ T cells, natural killer cells, monocytes, and conventional dendritic cells but not mucosa-associated innate T cells. Conventional T-cell, monocyte, and conventional dendritic cell responses in children were higher immediately after vaccination than after SARS-CoV-2 infection. The fold increase in CMI pre- to postvaccination did not differ between children previously infected with SARS-CoV-2 and those uninfected. Conclusions: Children aged 6 to 60 months who were vaccinated with a COVID-19 mRNA vaccine developed robust CMI responses, including adaptive and innate immunity.

20.
Nat Commun ; 13(1): 2623, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35551424

RESUMO

Plasmas are an indispensable materials engineering tool due to their unique ability to deliver a flux of species and energy to a surface. This energy flux serves to heat the surface out of thermal equilibrium with bulk material, thus enabling local physicochemical processes that can be harnessed for material manipulation. However, to-date, there have been no reports on the direct measurement of the localized, transient thermal response of a material surface exposed to a plasma. Here, we use time-resolved optical thermometry in-situ to show that the energy flux from a pulsed plasma serves to both heat and transiently cool the material surface. To identify potential mechanisms for this 'plasma cooling,' we employ time-resolved plasma diagnostics to correlate the photon and charged particle flux with the thermal response of the material. The results indicate photon-stimulated desorption of adsorbates from the surface is the most likely mechanism responsible for this plasma cooling.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA