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1.
Int J Sport Nutr Exerc Metab ; : 1-11, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38653456

RESUMO

The cyclical changes in sex hormones across the menstrual cycle (MC) are associated with various biological changes that may alter resting metabolic rate (RMR) and body composition estimates. Hormonal contraceptive (HC) use must also be considered given their impact on endogenous sex hormone concentrations and synchronous exogenous profiles. The purpose of this study was to determine if RMR and dual-energy X-ray absorptiometry body composition estimates change across the MC and differ compared with HC users. This was accomplished during a 5-week training camp involving naturally cycling athletes (n = 11) and HC users (n = 7 subdermal progestin implant, n = 4 combined monophasic oral contraceptive pill, n = 1 injection) from the National Rugby League Indigenous Women's Academy. MC phase was retrospectively confirmed via serum estradiol and progesterone concentrations and a positive ovulation test. HC users had serum estradiol and progesterone concentrations assessed at the time point of testing. Results were analyzed using general linear mixed model. There was no effect of MC phase on absolute RMR (p = .877), relative RMR (p = .957), or dual-energy X-ray absorptiometry body composition estimates (p > .05). There was no effect of HC use on absolute RMR (p = .069), relative RMR (p = .679), or fat mass estimates (p = .766), but HC users had a greater fat-free mass and lean body mass than naturally cycling athletes (p = .028). Our findings suggest that RMR and dual-energy X-ray absorptiometry body composition estimates do not significantly differ due to changes in sex hormones in a group of athletes, and measurements can be compared between MC phases or with HC usage without variations in sex hormones causing additional noise.

2.
Int J Sport Nutr Exerc Metab ; 34(2): 111-121, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38211577

RESUMO

The aim of this audit was to quantify female representation in research on heat adaptation. Using a standardized audit tool, the PubMed database was searched for heat adaptation literature from inception to February 2023. Studies were included if they investigated heat adaptation among female and male adults (≥18-50 years) who were free from noncommunicable diseases, with heat adaptation the primary or secondary outcome of interest. The number and sex of participants, athletic caliber, menstrual status, research theme, journal impact factor, Altmetric score, Field-Weighted Citation Impact, and type of heat exposure were extracted. A total of 477 studies were identified in this audit, including 7,707 participants with ∼13% of these being female. Most studies investigated male-only cohorts (∼74%, n = 5,672 males), with ∼5% (n = 360 females) including female-only cohorts. Of the 126 studies that included females, only 10% provided some evidence of appropriate methodological control to account for ovarian hormone status, with no study meeting best-practice recommendations. Of the included female participants, 40% were able to be classified to an athletic caliber, with 67% of these being allocated to Tier 2 (i.e., trained/developmental) or below. Exercise heat acclimation was the dominant method of heat exposure (437 interventions), with 21 studies investigating sex differences in exercise heat acclimation interventions. We recommend that future research on heat adaptation in female participants use methodological approaches that consider the potential impact of sexual dimorphism on study outcomes to provide evidence-based guidelines for female athletes preparing for exercise or competition in hot conditions.


Assuntos
Desempenho Atlético , Termotolerância , Adulto , Humanos , Masculino , Feminino , Aclimatação , Temperatura Alta , Exercício Físico
3.
Sports Med ; 53(Suppl 1): 25-48, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37878211

RESUMO

This narrative review evaluated the evidence for buffering agents (sodium bicarbonate, sodium citrate and beta-alanine), with specific consideration of three discrete scenarios: female athletes, extreme environments and combined buffering agents. Studies were screened according to exclusion and inclusion criteria and were analysed on three levels: (1) moderating variables (supplement dose and timing, and exercise test duration and intensity), (2) design factors (e.g., use of crossover or matched group study design, familiarisation trials) and (3) athlete-specific factors (recruitment of highly trained participants, buffering capacity and reported performance improvements). Only 19% of the included studies for the three buffering agents reported a performance benefit, and only 10% recruited highly trained athletes. This low transferability of research findings to athletes' real-world practices may be due to factors including the small number of sodium citrate studies in females (n = 2), no studies controlling for the menstrual cycle (MC) or menstrual status using methods described in recently established frameworks, and the limited number of beta-alanine studies using performance tests replicating real-world performance efforts (n = 3). We recommend further research into buffering agents in highly trained female athletes that control or account for the MC, studies that replicate the demands of athletes' heat and altitude camps, and investigations of highly trained athletes' use of combined buffering agents. In a practical context, we recommend developing evidence-based buffering protocols for individual athletes which feature co-supplementation with other evidence-based products, reduce the likelihood of side-effects, and optimise key moderating factors: supplement dose and timing, and exercise duration and intensity.


Assuntos
Atletas , Desempenho Atlético , Humanos , Feminino , Bicarbonato de Sódio , Exercício Físico , Citrato de Sódio , beta-Alanina , Ambientes Extremos
4.
Sci Rep ; 13(1): 9731, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37322075

RESUMO

The COVID-19 pandemic has had a significant impact on mental health. Identifying risk factors and susceptible subgroups will guide efforts to address mental health concerns during the pandemic and long-term management and monitoring after the pandemic. We aimed to examine associations of insecurity (concerns about food, health insurance, and/or money), social support, and change in family relationships with poor mental health and to explore disparities in these associations. An online survey was collected from 3952 US adults between May and August 2020. Symptoms of anxiety, depression, stress, and trauma-related disorders were assessed by the Generalized Anxiety Disorder 7-item scale, the Patient Health Questionnaire-9, the Perceived Stress Scale-4, and the Primary Care Post-Traumatic Stress Disorder Screen, respectively. Social support was measured by the Oslo Social Support Scale. Logistic regression was used and stratified analyses by age, race/ethnicity, and sex were performed. We found a higher prevalence of poor mental health among those who were younger, female, with lower socioeconomic status, and racial/ethnic minorities. Participants who were worried about money, health insurance, or food had higher odds of symptoms of anxiety (OR = 3.74, 95% CI: 3.06-4.56), depression (OR = 3.20, 95% CI: 2.67-3.84), stress (OR = 3.08, 95% CI: 2.67-3.57), and trauma-related disorders (OR = 2.93, 95% CI: 2.42-3.55) compared to those who were not. Compared to poor social support, moderate and strong social support was associated with lower odds of all four symptoms. Participants who had changes in relationships with parents, children, or significant others had worse mental health. Our findings identified groups at higher risk for poor mental health, which offers insights for implementing targeted interventions.


Assuntos
COVID-19 , Saúde Mental , Criança , Adulto , Feminino , Humanos , Pandemias , COVID-19/epidemiologia , Relações Familiares , Apoio Social , Ansiedade/epidemiologia , Depressão/epidemiologia
5.
Int J Sport Nutr Exerc Metab ; 33(4): 198-208, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37160293

RESUMO

The aim of this audit was to assess the representation of female athletes, dietary control methods, and gold standard female methodology that underpins the current guidelines for chronic carbohydrate (CHO) intake strategies for athlete daily training diets. Using a standardized audit, 281 studies were identified that examined high versus moderate CHO, periodized CHO availability, and/or low CHO, high fat diets. There were 3,735 total participants across these studies with only ∼16% of participants being women. Few studies utilized a design that specifically considered females, with only 16 studies (∼6%) including a female-only cohort and six studies (∼2%) with a sex-based comparison in their statistical procedure, in comparison to the 217 studies (∼77%) including a male-only cohort. Most studies (∼72%) did not provide sufficient information to define the menstrual status of participants, and of the 18 studies that did, optimal methodology for control of ovarian hormones was only noted in one study. While ∼40% of male-only studies provided all food and beverages to participants, only ∼20% of studies with a female-specific design used this approach for dietary control. Most studies did not implement strategies to ensure compliance to dietary interventions and/or control energy intake during dietary interventions. The literature that has contributed to the current guidelines for daily CHO intake is lacking in research that is specific to, or adequately addresses, the female athlete. Redressing this imbalance is of high priority to ensure that the female athlete receives evidence-based recommendations that consider her specific needs.


Assuntos
Atletas , Dieta , Carboidratos da Dieta , Humanos , Masculino , Feminino , Dieta/normas , Guias como Assunto , Caracteres Sexuais , Carboidratos da Dieta/administração & dosagem
6.
Alcohol Alcohol ; 58(3): 247-257, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-36864564

RESUMO

AIMS: To examine the association between alcohol consumption and mental health during the COVID-19 pandemic. METHODS: An anonymous online survey was distributed among US adults during May-August 2020 through social networks and ResearchMatch. We collected information on demographic, lifestyles and mental health symptoms including anxiety, depression, stress and post-traumatic stress disorder. Logistic regression models were used to examine the cross-sectional association between alcohol consumption and mental health symptoms. We also examined effect modification by race, age, gender, social support, financial insecurity and quarantine status. RESULTS: The analytical sample consists of 3623 adults. Stable drinking habits and regular drinking behaviors were found to co-exist with better mental health status. Participants who increased their alcohol use had higher odds of developing mental health disorders than those who maintained their pre-pandemic drinking habits. Additionally, participants who engaged in binge drinking during the pandemic had higher odds of depression and stress than those who did not. The associations regarding increased drinking and binge drinking in relation to adverse mental health outcomes were stronger among females, racial minorities, and individuals with financial concerns, poor social support and restricted quarantine status than their counterparts. CONCLUSIONS: During the early stage of the COVID-19 pandemic, increased alcohol use and binge drinking are cross-sectionally associated with higher odds of mental health disorders, which highlighted the need for targeted intervention to address the mental health needs of individuals who have engaged in these behaviors, especially among females, minorities, those with insecurities or with restricted quarantine status.


Assuntos
Consumo Excessivo de Bebidas Alcoólicas , COVID-19 , Adulto , Feminino , Humanos , COVID-19/epidemiologia , Saúde Mental , Pandemias , Consumo Excessivo de Bebidas Alcoólicas/psicologia , Estudos Transversais , Depressão/psicologia
7.
J Clin Nurs ; 32(5-6): 666-687, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36514246

RESUMO

AIMS AND OBJECTIVES: This integrative review aimed at systematically searching, analysing and synthesising multiple sources of evidence, to build a temporal understanding of nursing students' experiences of sexual harassment whilst on clinical placement, and to discuss the social context which enables this. BACKGROUND: Sexual harassment is highly prevalent in workplaces globally. Contemporary social understandings contextualise sexual harassment as a significant form of interpersonal violence. This is the first literature review to go beyond prevalence to synthesise the experience, implications and responses to sexual harassment encountered by student nurses on clinical placement. DESIGN: Whittemore and Knafl's (2005) integrative review methodology is used to structure a rigorous analysis and synthesis of evidence. METHODS: The PRISMA checklist supported sound reporting of the search strategy. Three databases (CINAHL, Scopus and Medline) were searched using a Boolean strategy. Papers with a significant focus on sexual harassment of nursing students in the clinical setting were included with no limitation on publication date. Papers were excluded if they were not published in English or were only published as abstracts. RESULTS: A synthesis of 26 papers demonstrated that sexual harassment has significant impacts on student nurses and the nursing profession. The intimacy of close body care, dominant social perceptions of nursing as women's work and the sexualisation of nurses increase student vulnerability to sexual harassment. Workplace power imbalances further exacerbate sexual harassment and shape responses to incidents. CONCLUSIONS: Sexual harassment of nursing students is widespread and impacts student well-being and learning. RELEVANCE TO CLINICAL PRACTICE: Education is a strong protective factor and should target students, clinicians, clinical facilitators and academics. Attention to workplace culture, and processes that support disclosure and reporting, is also required to meaningfully address the sexual harassment of nursing students.


Assuntos
Bacharelado em Enfermagem , Assédio Sexual , Estudantes de Enfermagem , Humanos , Feminino , Bacharelado em Enfermagem/métodos , Aprendizagem , Revelação
8.
Med Sci Sports Exerc ; 55(3): 569-580, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36251373

RESUMO

PURPOSE: The aim of this audit was to assess the representation of female athletes within the literature that has led to current guidelines for carbohydrate (CHO) intake in the acute periods surrounding exercise and the quality of this research. METHODS: We conducted a standardized audit of research assessing CHO loading protocols, CHO mouth rinse, and CHO intake before, during, and after exercise. RESULTS: A total of 937 studies were identified in this audit. There were a total of 11,202 participants across these studies, with only ~11% being women. Most studies involved male-only cohorts (~79%), with a mere 38 studies (~4%) involving female-only cohorts and 14 studies (~2%) including a methodological design for comparison of sex-based responses. The frequent use of incorrect terminology surrounding menstrual status and the failure of most studies (~69%) to provide sufficient information on the menstrual status of participants suggests incomplete understanding and concern for female-specific considerations among researchers. Of the 197 studies that included women, only 13 (~7%) provided evidence of acceptable methodological control of ovarian hormones, and no study met all best-practice recommendations. Of these 13 studies, only half also provided sufficient information regarding the athletic caliber of participants. The topics that received such scrutiny were CHO loading protocols and CHO intake during exercise. CONCLUSIONS: The literature that underpins the current guidelines for CHO intake in the acute periods around exercise is lacking in high-quality research that can contribute knowledge specific to the female athlete and sex-based differences. New research that considers ovarian hormones and sex-based differences is needed to ensure that the recommendations for acute CHO fueling provided to female athletes are evidence based.


Assuntos
Exercício Físico , Esportes , Humanos , Masculino , Feminino , Exercício Físico/fisiologia , Esportes/fisiologia , Atletas , Carboidratos , Hormônios , Carboidratos da Dieta
9.
J Racial Ethn Health Disparities ; 10(4): 1899-1909, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-35913541

RESUMO

AIMS: Little research has examined factors underlying COVID-19 vaccine hesitancy or refusal in Black and Asian individuals in England, among whom hesitancy tends to be higher than in the general population. This qualitative study aimed to gain an understanding of factors affecting hesitancy in Black and Asian individuals in England, to help address concerns about having the vaccine. METHOD: Ninety-five participants (51 women, 42 men, 2 other; 58% were aged between 30 and 49) recruited via a market recruitment agency, local Healthwatch networks, and using a snowballing method, participated in four activities on an online engagement platform, sharing their attitudes towards the COVID-19 vaccine roll-out, and factors shaping their beliefs and concerns, over 5 weeks from April to March 2021. RESULTS: Inductive thematic analysis revealed five themes: (1) a variety of views on the COVID-19 vaccine, (2) targeted messaging for Black and Asian people as counterproductive, (3) confusion over the purpose of the vaccine roll-out, (4) hesitancy to take the vaccine, and (5) local networks as a trusted source of information. CONCLUSIONS: Our findings suggest that respecting individuals' agency, transparency of information provided, and the independence of the bodies providing this information are important. Instead of targeted messaging, local networks should be used in campaigns to increase COVID-19 vaccine uptake among Black and Asian individuals.


Assuntos
Asiático , População Negra , Vacinas contra COVID-19 , COVID-19 , Hesitação Vacinal , Feminino , Humanos , Masculino , Asiático/psicologia , Asiático/estatística & dados numéricos , COVID-19/epidemiologia , COVID-19/etnologia , COVID-19/prevenção & controle , COVID-19/psicologia , Vacinas contra COVID-19/uso terapêutico , Inglaterra/epidemiologia , Pesquisa Qualitativa , Adulto , Pessoa de Meia-Idade , Hesitação Vacinal/etnologia , Hesitação Vacinal/psicologia , Hesitação Vacinal/estatística & dados numéricos , População Negra/psicologia , População Negra/estatística & dados numéricos
10.
Nutrients ; 14(16)2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-36014878

RESUMO

Micronutrient deficiencies and sub-optimal intakes among female athletes are a concern and are commonly prevented or treated with medical supplements. However, it is unclear how well women have been considered in the research underpinning current supplementation practices. We conducted an audit of the literature supporting the use of calcium, iron, and vitamin D. Of the 299 studies, including 25,171 participants, the majority (71%) of participants were women. Studies with exclusively female cohorts (37%) were also more prevalent than those examining males in isolation (31%). However, study designs considering divergent responses between sexes were sparse, accounting for 7% of the literature. Moreover, despite the abundance of female participants, the quality and quantity of the literature specific to female athletes was poor. Just 32% of studies including women defined menstrual status, while none implemented best-practice methodologies regarding ovarian hormonal control. Additionally, only 10% of studies included highly trained female athletes. Investigations of calcium supplementation were particularly lacking, with just two studies conducted in highly trained women. New research should focus on high-quality investigations specific to female athletes, alongside evaluating sex-based differences in the response to calcium, iron, and vitamin D, thus ensuring the specific needs of women have been considered in current protocols involving medical supplements.


Assuntos
Micronutrientes , Oligoelementos , Atletas , Cálcio , Cálcio da Dieta , Suplementos Nutricionais , Feminino , Humanos , Ferro , Masculino , Vitamina D , Vitaminas
11.
Br J Educ Technol ; 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35601603

RESUMO

The COVID-19 pandemic disrupted education across the world as campuses closed to restrict the spread of the virus. UK universities swiftly migrated to online delivery. The experiences of students and staff during this transition can inform our return to campus and our ability to deal with future disruption. This study draws on Moore's theory of transactional distance to understand factors influencing student study skills engagement and participation in online learning during this period. We surveyed students (n = 178) in a computing school at a UK university. A partial least squares (PLS) analysis was used to explore the influence of transactional distance (between students/teachers and between students/students), access to e-learning capital, and perceived usefulness on two measures: study skills engagement and participation in online collaborative activity. Results show that transactional distance influences participation, and e-learning capital influences study skills engagement. Our findings suggest that if universities continue with aspects of online learning for previously on-campus students they should provide access to infrastructure and training on utilising the online ecosystem to avoid disadvantaging students. Further investment in students' e-learning capital, such as signposting and adapting existing resources, is also necessary to support this key influence in study skills engagement.

12.
Nutrients ; 14(5)2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35267928

RESUMO

Although sports nutrition guidelines promote evidence-based practice, it is unclear whether women have been adequately included in the underpinning research. In view of the high usage rates of performance supplements by female athletes, we conducted a standardised audit of the literature supporting evidence-based products: ß-alanine, caffeine, creatine, glycerol, nitrate/beetroot juice and sodium bicarbonate. Within 1826 studies totalling 34,889 participants, just 23% of participants were women, although 34% of studies included at least one woman. Across different supplements, 0-8% of studies investigated women exclusively, while fewer (0-2%) were specifically designed to compare sex-based responses. The annual publication of female-specific studies was ~8 times fewer than those investigating exclusively male cohorts. Interestingly, 15% of the female participants were classified as international/world-class athletes, compared with 7% of men. Most studies investigated performance outcomes but displayed poorer representation of women (16% of participants), whereas health-focussed studies had the greatest proportion of female participants (35%). Only 14% of studies including women attempted to define menstrual status, with only three studies (~0.5%) implementing best practice methodologies to assess menstrual status. New research should target the efficacy of performance supplements in female athletes, and future sports nutrition recommendations should specifically consider how well female athletes have contributed to the evidence-base.


Assuntos
Medicina Esportiva , Esportes , Atletas , Suplementos Nutricionais , Feminino , Humanos , Masculino , Política Nutricional
13.
Int J Sport Nutr Exerc Metab ; 32(2): 114-127, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35168200

RESUMO

Female-specific research on sports science and sports medicine (SSSM) fails to mirror the increase in participation and popularity of women's sport. Females have historically been excluded from SSSM research, particularly because their physiological intricacy necessitates more complex study designs, longer research times, and additional costs. Consequently, most SSSM practices are based on research with men, despite potential problems in translation to females due to sexual dimorphism in biological and phenotypical parameters as well as differences in event characteristics (e.g., race distances/durations). Recognition that erroneous extrapolations may hamper the efforts of females to maximize their athletic potential has created an impetus to acknowledge and readdress the sex disparity in SSSM research. To direct the priorities for future research, it is prudent to first develop a comprehensive understanding of the gaps in current knowledge by systematically "auditing" the literature. By conducting audits of the literature to highlight underdeveloped topics or identify potential problems with the quality of research, this information can then be used to expediently direct new research activities. This paper therefore presents a standardized audit methodology to establish the representation of female athletes in subdisciplines of existing SSSM research, including a template for reporting the results of key metrics. This standardized audit process will enable comparisons over time and between research subdisciplines. This working guide provides an important step toward achieving sex equity across SSSM research, with the eventual goal of providing evidence-based recommendations specific to the female athlete.


Assuntos
Medicina Esportiva , Esportes , Atletas , Feminino , Humanos , Esportes/fisiologia
14.
Int J Sports Physiol Perform ; 17(2): 317-331, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34965513

RESUMO

Throughout the sport-science and sports-medicine literature, the term "elite" subjects might be one of the most overused and ill-defined terms. Currently, there is no common perspective or terminology to characterize the caliber and training status of an individual or cohort. This paper presents a 6-tiered Participant Classification Framework whereby all individuals across a spectrum of exercise backgrounds and athletic abilities can be classified. The Participant Classification Framework uses training volume and performance metrics to classify a participant to one of the following: Tier 0: Sedentary; Tier 1: Recreationally Active; Tier 2: Trained/Developmental; Tier 3: Highly Trained/National Level; Tier 4: Elite/International Level; or Tier 5: World Class. We suggest the Participant Classification Framework can be used to classify participants both prospectively (as part of study participant recruitment) and retrospectively (during systematic reviews and/or meta-analyses). Discussion around how the Participant Classification Framework can be tailored toward different sports, athletes, and/or events has occurred, and sport-specific examples provided. Additional nuances such as depth of sport participation, nationality differences, and gender parity within a sport are all discussed. Finally, chronological age with reference to the junior and masters athlete, as well as the Paralympic athlete, and their inclusion within the Participant Classification Framework has also been considered. It is our intention that this framework be widely implemented to systematically classify participants in research featuring exercise, sport, performance, health, and/or fitness outcomes going forward, providing the much-needed uniformity to classification practices.


Assuntos
Desempenho Atlético , Medicina Esportiva , Esportes , Atletas , Exercício Físico , Humanos , Estudos Retrospectivos
15.
J Am Med Inform Assoc ; 23(2): 428-34, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26209436

RESUMO

OBJECTIVES: This article summarizes past and current data mining activities at the United States Food and Drug Administration (FDA). TARGET AUDIENCE: We address data miners in all sectors, anyone interested in the safety of products regulated by the FDA (predominantly medical products, food, veterinary products and nutrition, and tobacco products), and those interested in FDA activities. SCOPE: Topics include routine and developmental data mining activities, short descriptions of mined FDA data, advantages and challenges of data mining at the FDA, and future directions of data mining at the FDA.


Assuntos
Mineração de Dados , Vigilância de Produtos Comercializados , United States Food and Drug Administration , Mineração de Dados/estatística & dados numéricos , Farmacovigilância , Estados Unidos
16.
J Transl Med ; 5: 26, 2007 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-17555571

RESUMO

The incidence of cancer increases significantly in later life, yet few pre-clinical studies of cancer immunotherapy use mice of advanced age. A novel vaccine delivery platform (VacciMax,VM) is described that encapsulates antigens and adjuvants in multilamellar liposomes in a water-in-oil emulsion. The therapeutic potential of VM-based vaccines administered as a single dose was tested in HLA-A2 transgenic mice of advanced age (48-58 weeks old) bearing large palpable TC1/A2 tumors. The VM-based vaccines contained one or more peptides having human CTL epitopes derived from HPV 16 E6 and E7. VM formulations contained a single peptide, a mixture of four peptides or the same four peptides linked together in a single long peptide. All VM formulations contained PADRE and CpG as adjuvants and ISA51 as the hydrophobic component of the water-in-oil emulsion. VM-formulated vaccines containing the four peptides as a mixture or linked together in one long peptide eradicated 19-day old established tumors within 21 days of immunization. Peptide-specific cytotoxic cellular responses were confirmed by ELISPOT and intracellular staining for IFN-gamma producing CD8+ T cells. Mice rendered tumor-free by vaccination were re-challenged in the opposite flank with 10 million HLF-16 tumor cells, another HLA-A2/E6/E7 expressing tumor cell line. None of these mice developed tumors following the re-challenge. In summary, this report describes a VM-formulated therapeutic vaccine with the following unprecedented outcome: a) eradication of large tumors (> 700 mm3) b) in mice of advanced age c) in less than three weeks post-immunization d) following a single vaccination.


Assuntos
Papillomavirus Humano 16/imunologia , Imunização/instrumentação , Neoplasias/imunologia , Neoplasias/patologia , Peptídeos/imunologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Envelhecimento/imunologia , Envelhecimento/patologia , Animais , Vacinas Anticâncer/imunologia , Linhagem Celular Tumoral , Citocinas/metabolismo , Humanos , Interferon gama/metabolismo , Espaço Intracelular/metabolismo , Camundongos , Baço/citologia , Coloração e Rotulagem
17.
J Transl Med ; 5: 20, 2007 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-17451606

RESUMO

BACKGROUND: Melanoma tumors are known to express antigens that usually induce weak immune responses of short duration. Expression of both tumor-associated antigens p53 and TRP2 by melanoma cells raises the possibility of simultaneously targeting more than one antigen in a therapeutic vaccine. In this report, we show that VacciMax (VM), a novel liposome-based vaccine delivery platform, can increase the immunogenicity of melanoma associated antigens, resulting in tumor elimination. METHODS: C57BL/6 mice bearing B16-F10 melanoma tumors were vaccinated subcutaneously 6 days post tumor implantation with a mixture of synthetic peptides (modified p53: 232-240, TRP-2: 181-188 and PADRE) and CpG. Tumor growth was monitored and antigen-specific splenocyte responses were assayed by ELISPOT. RESULTS: Vaccine formulated in VM increased the number of both TRP2- and p53-specific IFN-gamma producing splenocytes following a single vaccination. Vaccine formulated without VM resulted only in enhanced IFN-gamma producing splenocytes to one CTL epitopes (TRP2:180-188), suggesting that VM overcomes antigen dominance and enhances immunogenicity of multiple epitopes. Vaccination of mice bearing 6-day old B16-F10 tumors with both TRP2 and p53-peptides formulated in VM successfully eradicated tumors in all mice. A control vaccine which contained all ingredients except liposomes resulted in eradication of tumors in no more than 20% of mice. CONCLUSION: A single administration of VM is capable of inducing an effective CTL response to multiple tumor-associated antigens. The responses generated were able to reject 6-day old B16-F10 tumors.


Assuntos
Vacinas Anticâncer/imunologia , Melanoma Experimental/imunologia , Melanoma Experimental/terapia , Peptídeos/imunologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Vacinação/instrumentação , Animais , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Feminino , Interferon gama/biossíntese , Contagem de Linfócitos , Melanoma Experimental/prevenção & controle , Camundongos , Camundongos Endogâmicos C57BL , Baço/citologia , Baço/imunologia
18.
Proc Natl Acad Sci U S A ; 104(11): 4455-60, 2007 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-17360545

RESUMO

Tetraploid embryo complementation assay has shown that mouse ES cells alone are capable of supporting embryonic development and adult life of mice. Newly established F(1) hybrid ES cells allow the production of ES cell-derived animals at a high enough efficiency to directly make ES cell-based genetics feasible. Here we report the establishment and characterization of 12 new F(1) hybrid ES cell lines and the use of one of the best (G4) in a gain- and loss-of-function genetic study, where the in vivo phenotypes were assessed directly from ES cell-derived embryos. We found the generation of G4 ES cell-derived animals to be very efficient. Furthermore, even after two consecutive rounds of genetic modifications, the majority of transgenic lines retained the original potential of the parental lines; with 10-40% of chimeras producing ES cell-derived animals/embryos. Using these genetically altered ES cells, this success rate, in most cases, permitted the derivation of a sufficient number of mutants for initial phenotypic analyses only a few weeks after the establishment of the cell lines. Although the experimental design has to take into account a moderate level of uncontrolled damage on ES cell lines, our proof-of-principle experiment provides useful data to assist future designs harnessing the power of this technology to accelerate our understanding of gene function.


Assuntos
Células-Tronco Embrionárias/citologia , Camundongos Transgênicos , Mutação , Animais , Linhagem Celular , Cruzamentos Genéticos , Feminino , Teste de Complementação Genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Genéticos , Fenótipo , Plasmídeos/metabolismo , Transgenes
19.
Genesis ; 40(3): 131-8, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15493019

RESUMO

We generated a transgenic mouse line (tau::Cre) by targeting the Cre to the tau locus (Mapt). Based on previous reports on the expression of Tau during development, we expected the Cre recombinase to be expressed in a neuron-specific and pan-neuronal manner. However, intercrosses between the tau::Cre and the Cre-activatable reporter animals resulted in offspring with recombination either restricted to the nervous system or throughout the entire conceptus, indicating expression of Tau early in development. The percentage of neuron-specific excision was dependent on the Cre reporter used representing different Cre target sites in the mouse genome. In spite of the observed variability, our data suggest that the tau::Cre mouse line can be used for pan-neuronal recombination of floxed alleles when it is used with caution.


Assuntos
Integrases/genética , Neurônios/metabolismo , Recombinação Genética , Proteínas tau/genética , Animais , Cruzamentos Genéticos , Feminino , Regulação da Expressão Gênica , Marcação de Genes , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Camundongos Transgênicos , Especificidade de Órgãos , Proteínas tau/metabolismo
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