Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 86
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Breast Cancer Res Treat ; 199(2): 215-220, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37027122

RESUMEN

PURPOSE: DCIS has been shown to have a higher rate of positive margins following breast-conserving surgery (BCS) than invasive breast cancer. We aim to analyze certain factors of DCIS, specifically histologic grade and estrogen receptor (ER) status, in patients with positive surgical margins following BCS to determine if there is an association. METHODS: A retrospective review of our institutional patient registry was performed to identify women with DCIS and microinvasive DCIS who underwent BCS by a single surgeon from 1999 to 2021. Demographics and clinicopathologic characteristics between patients with and without positive surgical margins were compared using chi-square or Student's t-test. We assessed factors associated with positive margins using univariate and multivariable logistic regression. RESULTS: Of the 615 patients evaluated, there was no significant difference in demographics between the patients with and without positive surgical margins. Increasing tumor size was an independent risk factor for margin positivity (P = < 0.001). On univariate analysis both high histologic grade (P = 0.009) and negative ER status (P = < 0.001) were significantly associated with positive surgical margins. However, when adjusted in multivariable analysis, only negative ER status remained significantly associated with margin positivity (OR = 0.39 [95% CI 0.20-0.77]; P = 0.006). CONCLUSION: The study confirms increased tumor size as a risk factor for positive surgical margins. We also demonstrated that ER negative DCIS was independently associated with a higher rate of positive margins after BCS. Given this information, we can modify our surgical approach to reduce rate of positive margins in patients with large-sized ER negative DCIS.


Asunto(s)
Neoplasias de la Mama , Carcinoma Ductal de Mama , Carcinoma Intraductal no Infiltrante , Femenino , Humanos , Neoplasias de la Mama/cirugía , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/cirugía , Carcinoma Ductal de Mama/patología , Carcinoma Intraductal no Infiltrante/cirugía , Carcinoma Intraductal no Infiltrante/patología , Márgenes de Escisión , Mastectomía Segmentaria , Receptores de Estrógenos , Estudios Retrospectivos
2.
Clin Exp Immunol ; 210(2): 163-174, 2022 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-36053502

RESUMEN

Natural killer (NK) cells are important anti-viral effector cells. The function and phenotype of the NK cells that constitute an individual's NK cell repertoire can be influenced by ongoing or previous viral infections. Indeed, infection with human cytomegalovirus (HCMV) drives the expansion of a highly differentiated NK cell population characterized by expression of CD57 and the activating NKG2C receptor. This NK cell population has also been noted to occur in HIV-1-infected individuals. We evaluated the NK cells of HIV-1-infected and HIV-1-uninfected individuals to determine the relative frequency of highly differentiated CD57+NKG2C+ NK cells and characterize these cells for their receptor expression and responsiveness to diverse stimuli. Highly differentiated CD57+NKG2C+ NK cells occurred at higher frequencies in HCMV-infected donors relative to HCMV-uninfected donors and were dramatically expanded in HIV-1/HCMV co-infected donors. The expanded CD57+NKG2C+ NK cell population in HIV-1-infected donors remained stable following antiretroviral therapy. CD57+NKG2C+ NK cells derived from HIV-1-infected individuals were robustly activated by antibody-dependent stimuli that contained anti-HIV-1 antibodies or therapeutic anti-CD20 antibody, and these NK cells mediated cytolysis through NKG2C. Lastly, CD57+NKG2C+ NK cells from HIV-1-infected donors were characterized by reduced expression of the inhibitory NKG2A receptor. The abundance of highly functional CD57+NKG2C+ NK cells in HIV-1-infected individuals raises the possibility that these NK cells could play a role in HIV-1 pathogenesis or serve as effector cells for therapeutic/cure strategies.


Asunto(s)
Infecciones por VIH , Células Asesinas Naturales , Humanos , VIH-1 , Subfamília C de Receptores Similares a Lectina de Células NK , Fenotipo , Infecciones por VIH/inmunología
3.
Immunology ; 154(1): 38-49, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29355919

RESUMEN

The few initial formative studies describing non-specific and apparently spontaneous activity of natural killer (NK) cells have since multiplied into thousands of scientific reports defining their unique capacities and means of regulation. Characterization of the array of receptors that govern NK cell education and activation revealed an unexpected relationship with the major histocompatibility molecules that NK cells originally became well known for ignoring. Proceeding true to form, NK cells continue to up-end archetypal understanding of their ever-expanding capabilities. Discovery that the NK cell repertoire is extremely diverse and can be reshaped by particular viruses into unique subsets of adaptive NK cells challenges, or at least broadens, the definition of immunological memory. This review provides an overview of studies identifying adaptive NK cells, addressing the origins of NK cell memory and introducing the heretical concept of NK cells with extensive antigenic specificity. Whether these newly apparent properties reflect adaptive utilization of known NK cell attributes and receptors or a specially creative allocation from an undefined receptor array remains to be fully determined.


Asunto(s)
Inmunidad Adaptativa , Evolución Biológica , Memoria Inmunológica , Células Asesinas Naturales/inmunología , Animales , Antígenos/inmunología , Antígenos/metabolismo , Citomegalovirus/inmunología , Infecciones por Citomegalovirus/inmunología , Infecciones por Citomegalovirus/metabolismo , Infecciones por Citomegalovirus/virología , Interacciones Huésped-Patógeno , Humanos , Células Asesinas Naturales/metabolismo , Células Asesinas Naturales/virología , Fenotipo , Receptores Inmunológicos/inmunología , Receptores Inmunológicos/metabolismo
4.
BMC Fam Pract ; 19(1): 128, 2018 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-30053841

RESUMEN

BACKGROUND: Despite the risks, concussion symptoms often go underreported by athletes, leading to delayed or forgone treatment and increased potential for concussion recurrence. One of the most serious long-term consequences of sports-related concussions is Chronic Traumatic Encephelopathy (CTE), a disorder associated with progressive neurological deterioration. The purpose of this study was to explore former collegiate athletes' understanding of concussions and motivations behind concussion non-disclosure in order to better assist family medicine providers in screening for and managing a history of concussions. METHODS: Informed by the theoretical framework Social Cognitive Theory, we conducted focus groups with former collegiate athletes using a field-tested discussion guide. Discussions were transcribed, coded, and analyzed via content and thematic analyses using NVivo 10 software. RESULTS: Thirty-two former collegiate athletes (24.5 ± 2.9 years old, 59.4% female, 87.5% white) participated in 7 focus groups. Three predominant themes emerged: 1) Concussions are Part of the Game: Participants believed that concussions were part of sports, and that by agreeing to play a sport they were accepting the inherent risk of concussions. Importantly, many were not familiar with concussion symptoms and what constituted a concussion; 2) Hiding Concussion Symptoms: Participants said they often hid concussion symptoms from coaches and trainers in order to avoid being taken out of or missing games. Participants were able to hide their concussions because most symptoms were indiscernible to others; and 3) Misconceptions about Concussions in Low Contact Sports: Several participants did not understand that concussions could occur in all sports including low contact or noncontact sports. The former athletes who participated in low contact sports and experienced concussions attributed their concussions to personal clumsiness rather than their sport. CONCLUSIONS: Family medicine providers as well as coaches, athletic trainers, teachers, and parents/guardians should reinforce the message that concussions can occur in all sports and inform patients about the signs and symptoms of concussions. Further, providers should ask all patients if they engaged in high school or collegiate athletics; and if yes, to describe their hardest hit to their head in order to obtain a complete medical history.


Asunto(s)
Atletas , Traumatismos en Atletas , Conmoción Encefálica , Motivación , Médicos de Familia , Revelación de la Verdad , Adulto , Encefalopatía Traumática Crónica , Femenino , Grupos Focales , Humanos , Masculino , Tamizaje Masivo , Estados Unidos , Universidades , Adulto Joven
5.
AIDS Res Ther ; 14(1): 41, 2017 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-28893274

RESUMEN

Chronic infection with human immunodeficiency virus (HIV) causes HIV-specific CD8+ T cell dysfunction and exhaustion. The strong association between non-progression and maintenance of HIV-specific CD8+ T cell cytokine production and proliferative capacities suggests that invigorating CD8+ T cell immune responses would reduce viremia and slow disease progression. A series of studies have demonstrated that sequence variants of native immunogenic peptides can generate more robust CD8+ T cell responses and that stimulation with these 'heteroclitic' peptides can steer responses away from the phenotypic and functional attributes of exhaustion acquired during chronic HIV infection. Incorporation of heteroclitic peptide stimulation within therapeutic vaccines could favour induction of more effective cellular antiviral responses, and in combination with 'shock and kill' strategies, contribute towards HIV cure.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , VIH-1/inmunología , Péptidos/inmunología , Vacunas contra el SIDA/uso terapéutico , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/patología , Linfocitos T CD8-positivos/virología , Infecciones por VIH/inmunología , Infecciones por VIH/terapia , Humanos , Inmunidad Celular , Interferón gamma/inmunología , Interleucina-2/inmunología , Activación de Linfocitos , Péptidos/química , Receptores de Antígenos de Linfocitos T/inmunología
6.
Ann Surg Oncol ; 22(2): 416-21, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25223926

RESUMEN

BACKGROUND: One of the most challenging procedures in breast surgery is the skin-sparing mastectomy (SSM). Various techniques and incisions have evolved that characterize this procedure; however, what is common in all of them is the smaller the incision, the more difficult it is to develop the skin flaps. METHODS: A procedure was developed that incorporates the use of liposuction cannulas (without suction) to create the skin flaps. The technique and results are described in this manuscript. RESULTS: From October of 2012 to April 2014, 289 mastectomies (171 patients) were performed using the CAFE procedure on women of all shapes and sizes. Postoperatively, no problems were experienced with flap viability using this technique. The main difference in side effects between the CAFE technique and other standard techniques for developing flaps in SSMs was more bruising than normal, but this resolved rapidly. The results for use of this technique were consistently impressive. The learning curve for this procedure is very short, especially for those who perform SSMs using sharp technique (scissors). Residents and fellows became proficient with the CAFE technique in a relatively short amount of time. Plastic surgeons were pleased with the cosmetic outcomes of their reconstructions that follow this type of mastectomy. Patients were extremely satisfied with their reconstructions as well. CONCLUSIONS: Incorporating the use of liposuction cannulas (without suction) makes the creation of flaps for SSM a relatively simple and rapid method. It is especially useful to assist in developing skin flaps with even the smallest of skin incisions.


Asunto(s)
Catéteres , Mastectomía/métodos , Colgajos Quirúrgicos , Neoplasias de la Mama/cirugía , Femenino , Humanos , Curva de Aprendizaje
7.
J Immunol ; 191(6): 3308-18, 2013 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-23960237

RESUMEN

Hepatitis C virus (HCV) successfully evades the immune system and establishes chronic infection in ∼80% of cases. Immune evasion may involve modulating NK cell functions. Therefore, we developed a short-term assay to assess immediate effects of HCV-infected cells on ex vivo NK cytotoxicity and cytokine production. Natural cytotoxicity, Ab-dependent cell-mediated cytotoxicity, IFN-γ production, and TNF-α production were all significantly inhibited by short-term direct exposure to HCV-infected hepatoma-derived Huh-7.5 cells. Inhibition required cell-to-cell contact and increased together with multiplicity of infection and HCV protein levels. Blocking potential interaction between HCV E2 and NK CD81 did not abrogate NK cell inhibition mediated by HCV-infected cells. We observed no change in expression levels of NKG2D, NKG2A, NKp46, or CD16 on NK cells exposed to HCV-infected Huh-7.5 cells for 5 h or of human histocompatibility-linked leukocyte Ag E on HCV-infected compared with uninfected Huh-7.5 cells. Inhibition of ex vivo NK functions did correspond with reduced surface expression of the natural cytotoxicity receptor NKp30, and downregulation of NKp30 was functionally reflected in reduced anti-NKp30 redirected lysis of P815 cells. Infection of Huh-7.5 cells with HCV JFH1(T) increased surface binding of an NKp30-IgG1 Fcγ fusion protein, suggesting upregulation of an antagonistic NKp30 ligand on HCV-infected cells. Our assay demonstrates rapid inhibition of critical NK cell functions by HCV-infected cells. Similar localized effects in vivo may contribute to establishment of chronic HCV infection and associated phenotypic and functional changes in the NK population.


Asunto(s)
Hepacivirus/inmunología , Hepatitis C/inmunología , Células Asesinas Naturales/inmunología , Receptor 3 Gatillante de la Citotoxidad Natural/biosíntesis , Línea Celular , Técnicas de Cocultivo , Citotoxicidad Inmunológica/inmunología , Regulación hacia Abajo , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Técnica del Anticuerpo Fluorescente Indirecta , Hepatitis C/metabolismo , Humanos , Técnicas Inmunológicas
8.
AIDS Res Ther ; 11: 30, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25237383

RESUMEN

BACKGROUND: The CD5 protein antagonizes phosphorylation events downstream of T cell receptor (TCR) engagement to decrease T cell responsiveness. CD5-negative T cell clones respond preferentially over their CD5(+) counterparts against cells with low human histocompatibility-linked leukocyte antigen (HLA) levels. In human immunodeficiency virus type 1 (HIV-1) infection, CD5(-)CD8(+) T cells increase in prevalence with disease progression. METHODS: To investigate potential causes of this expansion of CD5(-)CD8(+) T cells in HIV-1 infection, we compared CD5 expression on CD8(+) T cells reactive against HIV-1 peptides, common viral peptides and a self peptide that together span a broad range of TCR avidities in the context of the common HLA-A2 class I restriction molecule. Following stimulation, CD5 expression on peptide-specific CD8(+) T cells was assessed by flow cytometry. RESULTS: In healthy controls, there was no significant difference in the CD5(+) percentage of CD8(+) T cells specific for common viral peptides, but a lower percentage of those responding against a common self peptide expressed CD5. The same relationship occurred in HIV-infected individuals, however, a lower percentage of HIV peptide-specific CD8(+) T cells than other viral peptide-specific CD8(+) T cells expressed CD5. In terms of overall CD5 expression level at the peptide-specific responder population level, HIV-specific CD8(+) T cells resembled those responsive against the self peptide, despite much higher avidity TCR/HLA/peptide interactions. CONCLUSIONS: This deficit in CD5 expression selective for HIV-specific CD8(+) T cells is consistent with in vivo adaptation to low avidity HIV peptide variants and has potential consequences for CD8(+) T cell expansion, cross-reactivity and autoreactivity.

9.
PLoS One ; 19(6): e0305898, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38935671

RESUMEN

The HIV program in Newfoundland and Labrador (NL) provides care for all persons living with HIV (PLWH) in NL, yet progress toward UNAIDS 95-95-95 goals for diagnosis, linkage to care and viral suppression has not previously been documented. This analysis describes engagement in HIV care and virologic outcomes for the NL cohort in 2016 and 2019 and compares this data to the Canadian HIV Observational Cohort (CANOC). A retrospective review of the NL clinic included adults aged >18 years and descriptive statistics for demographics, risk factors, and clinical variables were assessed and compared using χ2 test or Fisher's Exact test (categorical) or Wilcoxon Sum Rank test (continuous). Engagement in care and virologic outcomes for the NL cohort were consistently high over the 2016 to 2019 period with > 98% on antiretroviral therapy (ART), and > 96% having a suppressed virus load. Engagement in care and virologic outcomes among PLWH in NL is high and compares favorably to a national cohort.


Asunto(s)
Infecciones por VIH , Organización Mundial de la Salud , Humanos , Infecciones por VIH/epidemiología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Terranova y Labrador/epidemiología , Femenino , Masculino , Adulto , Estudios Retrospectivos , Persona de Mediana Edad , Carga Viral , Fármacos Anti-VIH/uso terapéutico
10.
Behav Genet ; 43(2): 141-50, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23299959

RESUMEN

We examined shared and distinct genetic influences among standard measures of pulmonary functions: ratio of forced expiratory volume at 1 s to forced vital capacity (FEV1/FVC) and percent predicted values for forced expiratory volume at 1 s (FEV1%p), forced expiratory flow (FEFmax%p), and maximal voluntary ventilation (MVV%p) in 978-1,048 middle-aged (mean age = 55 years) male-male twins from the Vietnam Era Twin Study of Aging. A common latent factor (h(2) = 0.30) accounted for the correlations among these measures. This factor accounted for 54-81 % of the heritability of FEV1%p, FEFmax%p and MVV%p, but only explained 16 % of the heritability of FEV1/FVC. The remaining heritability of FEV1/FVC was explained by genetic influences independent of the common factor. Our findings suggest that while a common latent phenotype accounts for the relationships among different pulmonary function measures, the majority of genetic influences underlying FEV1/FVC--an index of pulmonary obstruction--are distinct from those underlying other pulmonary function measures.


Asunto(s)
Volumen Espiratorio Forzado/genética , Capacidad Vital/genética , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Pruebas de Función Respiratoria , Gemelos Dicigóticos , Gemelos Monocigóticos
11.
J Sleep Res ; 22(5): 519-26, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23509903

RESUMEN

Poor sleep quality is a risk factor for a number of cognitive and physiological age-related disorders. Identifying factors underlying sleep quality are important in understanding the etiology of these age-related health disorders. We investigated the extent to which genes and the environment contribute to subjective sleep quality in middle-aged male twins using the classical twin design. We used the Pittsburgh Sleep Quality Index to measure sleep quality in 1218 middle-aged twin men from the Vietnam Era Twin Study of Aging (mean age = 55.4 years; range 51-60; 339 monozygotic twin pairs, 257 dizygotic twin pairs, 26 unpaired twins). The mean PSQI global score was 5.6 [SD = 3.6; range 0-20]. Based on univariate twin models, 34% of variability in the global PSQI score was due to additive genetic effects (heritability) and 66% was attributed to individual-specific environmental factors. Common environment did not contribute to the variability. Similarly, the heritability of poor sleep-a dichotomous measure based on the cut-off of global PSQI>5-was 31%, with no contribution of the common environment. Heritability of six of the seven PSQI component scores (subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, and daytime dysfunction) ranged from 0.15 to 0.31, whereas no genetic influences contributed to the use of sleeping medication. Additive genetic influences contribute to approximately one-third of the variability of global subjective sleep quality. Our results in middle-aged men constitute a first step towards examination of the genetic relationship between sleep and other facets of aging.


Asunto(s)
Ambiente , Sueño/genética , Sueño/fisiología , Gemelos Dicigóticos/genética , Gemelos Monocigóticos/genética , Envejecimiento/genética , Humanos , Masculino , Persona de Mediana Edad , Trastornos del Sueño-Vigilia/genética , Trastornos del Sueño-Vigilia/fisiopatología , Factores de Tiempo
12.
Am J Med Genet B Neuropsychiatr Genet ; 162B(7): 762-9, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24132908

RESUMEN

Factors determining who develops PTSD following trauma are not well understood. The €4 allele of the apolipoprotein E (apoE) gene is associated with dementia and unfavorable outcome following brain insult. PTSD is also associated with dementia. Given evidence that psychological trauma adversely affects the brain, we hypothesized that the apoE genotype moderates effects of psychological trauma on PTSD pathogenesis. To investigate the moderation of the relationship between PTSD symptoms and combat exposure, we used 172 participants with combat trauma sustained during the Vietnam War. PTSD symptoms were the dependent variable and number of combat experiences, apoE genotype, and the combat experiences × apoE genotype interaction were predictors. We also examined the outcome of a diagnosis of PTSD (n = 39) versus no PTSD diagnosis (n = 131). The combat × apoE genotype interaction was significant for both PTSD symptoms (P = .014) and PTSD diagnosis (P = .009). ApoE genotype moderates the relationship between combat exposure and PTSD symptoms. Although the pathophysiology of PTSD is not well understood, the €4 allele is related to reduced resilience of the brain to insult. Our results are consistent with the €4 allele influencing the effects of psychological trauma on the brain, thereby affecting the risk of PTSD.


Asunto(s)
Apolipoproteínas E/genética , Trastornos de Combate/genética , Interacción Gen-Ambiente , Trastornos por Estrés Postraumático/genética , Envejecimiento/genética , Genotipo , Encuestas Epidemiológicas , Humanos , Persona de Mediana Edad , Análisis de Regresión , Trastornos por Estrés Postraumático/diagnóstico , Gemelos/genética , Vietnam
13.
Viruses ; 15(4)2023 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-37112977

RESUMEN

Some SARS-CoV-2-exposed individuals develop immunity without overt infection. We identified 11 individuals who were negative by nucleic acid testing during prolonged close contact and with no serological diagnosis of infection. As this could reflect natural immunity, cross-reactive immunity from previous coronavirus exposure, abortive infection due to de novo immune responses, or other factors, our objective was to characterize immunity against SARS-CoV-2 in these individuals. Blood was processed into plasma and peripheral blood mononuclear cells (PBMC) and screened for IgG, IgA, and IgM antibodies (Ab) against SARS-CoV-2 and common ß-coronaviruses OC43 and HKU1. Receptor blocking activity and interferon-alpha (IFN-α) in plasma were also measured. Circulating T cells against SARS-CoV-2 were enumerated and CD4+ and CD8+ T cell responses discriminated after in vitro stimulation. Exposed uninfected individuals were seronegative against SARS-CoV-2 spike (S) and selectively reactive against OC43 nucleocapsid protein (N), suggesting common ß-coronavirus exposure induced Ab cross-reactive against SARS-CoV-2 N. There was no evidence of protection from circulating angiotensin-converting enzyme (ACE2) or IFN-α. Six individuals had T cell responses against SARS-CoV-2, with four involving CD4+ and CD8+ T cells. We found no evidence of protection from SARS-CoV-2 through innate immunity or immunity induced by common ß-coronaviruses. Cellular immune responses against SARS-CoV-2 were associated with time since exposure, suggesting that rapid cellular responses may contain SARS-CoV-2 infection below the thresholds required for a humoral response.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Leucocitos Mononucleares , Linfocitos T CD8-positivos , Interferón-alfa , Anticuerpos Antivirales , Inmunidad Celular , Glicoproteína de la Espiga del Coronavirus
14.
JCI Insight ; 8(15)2023 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-37338994

RESUMEN

Antibodies capable of neutralizing SARS-CoV-2 are well studied, but Fc receptor-dependent antibody activities that can also significantly impact the course of infection have not been studied in such depth. Since most SARS-CoV-2 vaccines induce only anti-spike antibodies, here we investigated spike-specific antibody-dependent cellular cytotoxicity (ADCC). Vaccination produced antibodies that weakly induced ADCC; however, antibodies from individuals who were infected prior to vaccination (hybrid immunity) elicited strong anti-spike ADCC. Quantitative and qualitative aspects of humoral immunity contributed to this capability, with infection skewing IgG antibody production toward S2, vaccination skewing toward S1, and hybrid immunity evoking strong responses against both domains. A combination of antibodies targeting both spike domains support strong antibody-dependent NK cell activation, with 3 regions of antibody reactivity outside the receptor-binding domain (RBD) corresponding with potent anti-spike ADCC. Consequently, ADCC induced by hybrid immunity with ancestral antigen was conserved against variants containing neutralization escape mutations in the RBD. Induction of antibodies recognizing a broad range of spike epitopes and eliciting strong and durable ADCC may partially explain why hybrid immunity provides superior protection against infection and disease compared with vaccination alone, and it demonstrates that spike-only subunit vaccines would benefit from strategies that induce combined anti-S1 and anti-S2 antibody responses.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Vacunas contra la COVID-19 , Citotoxicidad Celular Dependiente de Anticuerpos , Inmunidad Humoral , Inmunoglobulina G
15.
Vaccines (Basel) ; 11(9)2023 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-37766138

RESUMEN

Mucosal IgA is widely accepted as providing protection against respiratory infections, but stimulation of mucosal immunity, collection of mucosal samples and measurement of mucosal IgA can be problematic. The relationship between mucosal and circulating IgA responses is unclear, however, whole blood is readily collected and circulating antigen-specific IgA easily measured. We measured circulating IgA against SARS-CoV-2 spike (S) to investigate vaccine- and infection-induced production and correlation with protection. Circulating IgA against ancestral (Wuhan-Hu-1) and Omicron (BA.1) S proteins was measured at different time points in a total of 143 subjects with varied backgrounds of vaccination and infection. Intramuscular vaccination induced circulating anti-SARS-CoV-2 S IgA. Subjects with higher levels of vaccine-induced IgA against SARS-CoV-2 S (p = 0.0333) or receptor binding domain (RBD) (p = 0.0266) were less likely to experience an Omicron breakthrough infection. The same associations did not hold for circulating IgG anti-SARS-CoV-2 S levels. Breakthrough infection following two vaccinations generated stronger IgA anti-SARS-CoV-2 S responses (p = 0.0002) than third vaccinations but did not selectively increase circulating IgA against Omicron over ancestral S, indicating immune imprinting of circulating IgA responses. Circulating IgA against SARS-CoV-2 S following breakthrough infection remained higher than vaccine-induced levels for over 150 days. In conclusion, intramuscular mRNA vaccination induces circulating IgA against SARS-CoV-2 S, and higher levels are associated with protection from breakthrough infection. Vaccination with ancestral S enacts imprinting within circulating IgA responses that become apparent after breakthrough infection with Omicron. Breakthrough infection generates stronger and more durable circulating IgA responses against SARS-CoV-2 S than vaccination alone.

16.
Neuroimage ; 59(2): 1123-31, 2012 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-21983185

RESUMEN

The hippocampus expresses a large number of androgen receptors; therefore, in men it is potentially vulnerable to the gradual age-related decline of testosterone levels. In the present study we sought to elucidate the nature of the relationship between testosterone and hippocampal volume in a sample of middle-aged male twins (average age 55.8 years). We found no evidence for a correlation between testosterone level and hippocampal volume, as well as no indication of shared genetic influences. However, a significant moderating effect of testosterone on the genetic and environmental determinants of hippocampal volume was observed. Genetic influences on hippocampal volume increased substantially as a function of increasing testosterone level, while environmental influences either decreased or remained stable. These findings provide evidence for an apparent gene-by-hormone interaction on hippocampal volume. To the best of our knowledge, this is the first study to demonstrate that the heritability of a brain structure in adults may be modified by an endogenous biological factor.


Asunto(s)
Hipocampo/anatomía & histología , Hipocampo/fisiología , Testosterona/sangre , Gemelos/genética , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos/fisiología
17.
Neuroimage ; 60(3): 1686-95, 2012 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-22500923

RESUMEN

The estimation of cortical thickness is in part dependent on the degree of contrast in T1 signal intensity between white matter and gray matter along the cortical mantle. The ratio of white matter to gray matter signal (WM/GM contrast) has been found to vary as a function of age and Alzheimer's disease status, suggesting a biological component to what might otherwise be labeled as a nuisance variable. The aim of the present study was to determine if measures of WM/GM contrast are genetically influenced, as well as the degree to which this phenotype may be related to the genetic and environment determinants of cortical thickness. Participants were 514 male twins (130 monozygotic, 97 dizygotic pairs, and 60 unpaired individuals) from the Vietnam Era Twin Study of Aging. Ages ranged from 51 to 59 years. Measures of WM/GM contrast and cortical thickness were derived for 66 cortical regions of interest (ROI) using FreeSurfer-based methods. Univariate and bivariate twin analyses were used in order to estimate the heritability of WM/GM contrast, as well as the degree of shared genetic and environmental variance between WM/GM contrast and cortical thickness. WM/GM contrast was found to be significantly heritable in the majority of ROIs. The average heritability across individual ROIs was highest in the occipital lobe (.50), and lowest in the cingulate cortex (.24). Significant phenotypic correlations between WM/GM contrast and cortical thickness were observed for most of the ROIs. The majority of the phenotypic correlations were negative, ranging from ?.11 to ?.54. Of the 66 associations, only 17 significant genetic correlations were found, ranging from ?.16 to ?.34, indicating small amounts of shared genetic variance. The majority of the phenotypic correlations were accounted for by small unique environmental effects common between WM/GM contrast and cortical thickness. These findings demonstrate that like cortical thickness, WM/GM contrast is a genetically influenced brain structure phenotype. The lack of significant genetic correlations with cortical thickness suggests that this measure potentially represents a unique source of genetic variance, one that has yet to be explored by the field of imaging genetics.


Asunto(s)
Envejecimiento/genética , Envejecimiento/patología , Corteza Cerebral/patología , Ambiente , Fibras Nerviosas Mielínicas/patología , Neuronas/patología , Gemelos/genética , Encéfalo , Estudios de Asociación Genética , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Fenotipo , Polimorfismo de Nucleótido Simple/genética , Gemelos/estadística & datos numéricos , Estados Unidos , Veteranos/estadística & datos numéricos , Guerra de Vietnam
18.
Behav Genet ; 42(1): 107-20, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21688193

RESUMEN

Hypertension is a risk factor for cognitive decline, but the mechanisms underlying the effects of hypertension on cognition, particularly in midlife, are unclear. We examined whether hypertension modifies genetic influences on individual differences in cognition. Nine cognitive domains and general cognitive ability were assessed in a sample of 1,237 male twins aged 51-60 who were divided into three blood pressure groups: non-hypertensive; medicated hypertensive; and unmedicated hypertensive. Heritability was significantly lower among unmedicated hypertensives compared to medicated hypertensives and non-hypertensives for visual-spatial ability (p = 0.013) and episodic memory (p = 0.004). There were no heritability differences between non-hypertensives and medicated hypertensives. In addition, there were no significant differences in mean level cognition across the three blood pressure groups. These results suggest that in middle-aged men, untreated hypertension suppresses normal genetic influences on individual differences in certain domains of cognition prior to the emergence of hypertension-related effects on cognitive performance. These results further suggest that antihypertensive medication may protect against or reverse this effect.


Asunto(s)
Trastornos del Conocimiento/complicaciones , Cognición , Hipertensión/genética , Envejecimiento , Antihipertensivos/farmacología , Presión Sanguínea , Trastornos del Conocimiento/genética , Humanos , Masculino , Memoria , Persona de Mediana Edad , Modelos Genéticos , Factores de Riesgo
19.
Anthrozoos ; 25(4): 441-456, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25580056

RESUMEN

There is growing evidence that pet ownership and human-animal interaction (HAI) have benefits for human physical and psychological well-being. However, there may be pre-existing characteristics related to patterns of pet ownership and interactions with pets that could potentially bias results of research on HAI. The present study uses a behavioral genetic design to estimate the degree to which genetic and environmental factors contribute to individual differences in frequency of play with pets among adult men. Participants were from the ongoing longitudinal Vietnam Era Twin Study of Aging (VETSA), a population-based sample of 1,237 monozygotic (MZ) and dizygotic (DZ) twins aged 51-60 years. Results demonstrate that MZ twins have higher correlations than DZ twins on frequency of pet play, suggesting that genetic factors play a role in individual differences in interactions with pets. Structural equation modeling revealed that, according to the best model, genetic factors accounted for as much as 37% of the variance in pet play, although the majority of variance (63-71%) was due to environmental factors that are unique to each twin. Shared environmental factors, which would include childhood exposure to pets, overall accounted for <10% of the variance in adult frequency of pet play, and were not statistically significant. These results suggest that the effects of childhood exposure to pets on pet ownership and interaction patterns in adulthood may be mediated primarily by genetically-influenced characteristics.

20.
NPJ Vaccines ; 7(1): 122, 2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36271095

RESUMEN

Hybrid immunity induced by vaccination following recovery from SARS-CoV-2 infection is more robust than immunity induced by either infection or vaccination alone. To investigate how infection severity influenced the strength and character of subsequent vaccine-induced humoral or cellular immune responses against SARS-CoV-2, we assessed humoral and cellular immune responses against SARS-CoV-2 following recovery from infection, vaccine dose 1 and vaccine dose 2 in 35 persons recovered from COVID-19. Persons with polymerase chain reaction or serologically confirmed SARS-CoV-2 infection were recruited into a study of immunity against SARS-CoV-2. Self-reported symptoms categorized them as experiencing asymptomatic, mild, moderate or severe infection based on duration, intensity and need for hospitalization. Whole blood was obtained before vaccination and after first and second doses. Humoral immunity was assessed by ELISA and cellular immunity by ELISpot and intracellular flow cytometry. Responses were compared between groups recovered from either asymptomatic/mild (n = 14) or moderate/severe (n = 21) infection. Most subjects experienced robust increases in humoral and cellular immunity against SARS-CoV-2 spike (S) protein following 1 vaccination. Quantitative responses to second vaccination were marginal when measured 2.5 months afterwards and moderate or severe infection maintained stronger responses. Polyfunctional CD8+ T cell responses were largely restricted to subjects recovered from moderate or severe infection. One vaccine dose triggered stronger immune responses than in a comparable group never infected with SARS-CoV-2, while the second dose produced only minor lasting increases in humoral or cellular responses. Infection history should be considered in planning COVID-19 vaccine administration.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA