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1.
Res Sq ; 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36747740

RESUMO

Apical periodontitis (AP) is a common consequence of root canal infection leading to periapical bone resorption. Microbial and host genetic factors, and their interactions, have been shown to play a role in AP development and progression. Variations in a few genes have been reported in association with AP, however, the lack of genome-wide studies has hindered progress in understanding the mechanisms involved in AP. Here, we report the first genome-wide association study of AP in a well-characterized population. Male and female adults (n=932) presenting with deep caries with AP (cases) or without AP (controls) were included. Genotyping was performed using the Illumina Expanded Multi-Ethnic Genotyping Array. Single-variant association testing was performed adjusting for sex and five principal components. Subphenotype association testing, analyses of genetically regulated gene expression, polygenic risk score and phenome-wide association (PheWAS) analyses were also performed. Eight loci reached near-genome-wide significant association with AP (p < 5 x 10-6); gene-focused analyses replicated three previously reported associations (p < 8.9 x 10-5). Sex-specific and subphenotype analyses revealed additional significant associations with variants genome-wide. Functionally oriented gene-based analyses revealed eight genes significantly associated with AP (p < 5 x 10-5), and PheWAS analysis revealed 33 phecodes associated with AP risk score (p < 3.08 x 10-5). This study identified novel genes/loci contributing to AP and revealed specific contributions to AP risk in males and females. Importantly, we identified additional systemic conditions significantly associated with AP risk. Our findings provide strong evidence for host-mediated effects on AP susceptibility.

2.
J Bioeth Inq ; 17(4): 531-534, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32840841

RESUMO

To say that coronavirus is highly visible is a massive understatement in terms of its omnipresence in our lives and media coverage concerning it, yet also clearly untrue in terms of the virus itself. COVID-19 is our invisible enemy, changing our lives radically without ever revealing itself directly. In this paper I explore its invisibility and how it relates to and exposes other invisible enemies we are and have been fighting, in many cases without even realizing. First, I analyse the virus itself and how its stealthy nature has transformed our lives. Second, I describe how the invisible epidemic of social media sharing of fake news about the virus worsens the situation further. Third, I explore how the virus has revealed to us what really matters in our lives and has forced us to re-evaluate our priorities. Fourth, I go on to explore the underlying structural weaknesses and disparities in society that have been exposed by the virus but previously remained unconsidered for so long that they too have become camouflaged, even if their effects are all too apparent; like the virus, neoliberal capitalism is an invisible enemy that has made prisoners of us all. I conclude by suggesting that the coronavirus pandemic represents a hidden opportunity to overcome perhaps the biggest invisible enemy of all: the moral distance that separates us from others. Only by rendering the rest of humanity morally visible to ourselves can we overcome capitalism and stop treating other people as invisible enemies.


Assuntos
COVID-19 , Equidade em Saúde/ética , Ciências Humanas , Princípios Morais , Pandemias , SARS-CoV-2 , COVID-19/virologia , Capitalismo , Coronavirus , Infecções por Coronavirus , Humanos , Meios de Comunicação de Massa , Metáfora , Mídias Sociais , Valores Sociais
3.
Public Health ; 149: 120-129, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28595064

RESUMO

OBJECTIVE: In the last two decades international public-private partnerships have become increasingly important to improving public health in low- and middle-income countries. Governments realize that involving the private sector in projects for financing, innovation, development, and distribution can make a valuable contribution to overcoming major health challenges. Private-public partnerships for health can generate numerous benefits but may also raise some concerns. To guide best practice for public-private partnerships for health to maximize benefits and minimize risks, the first step is to identify potential benefits, challenges, and motives. We define motives as the reasons why private partners enter partnerships with a public partner. STUDY DESIGN: We conducted a systematic review of the literature using the PRISMA guidelines. METHOD: We reviewed the literature on the benefits and challenges of public-private partnerships for health in low- and middle-income countries provided by international pharmaceutical companies and other health-related companies. We provide a description of these benefits, challenges, as well as of motives of private partners to join partnerships. An approach of systematic categorization was used to conduct this research. RESULT: We identified six potential benefits, seven challenges, and three motives. Our main finding was a significant gap in the available academic literature on this subject. Further empirical research using both qualitative and quantitative approaches is required. From the limited information that is readily available, we conclude that public-private partnerships for health imply several benefits but with some noticeable and crucial limitations. CONCLUSION: In this article, we provide a description of these benefits and challenges, discuss key themes, and conclude that empirical research is required to determine the full extent of the challenges addressed in the literature.


Assuntos
Países em Desenvolvimento , Cooperação Internacional , Saúde Pública , Parcerias Público-Privadas/organização & administração , Conflito de Interesses , Acessibilidade aos Serviços de Saúde/economia , Humanos , Parcerias Público-Privadas/ética , Medição de Risco , Responsabilidade Social
4.
Transl Psychiatry ; 6(7): e849, 2016 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-27378549

RESUMO

Memory loss is the most profound clinical manifestation in Alzheimer's disease (AD); however, the molecular mechanisms underlying these deficits are poorly understood. Identification of the molecular pathways involved in the onset of cognitive deficits may lead to the identification of key events in the pathogenesis of AD. Using isobaric tags for relative and absolute quantitation (iTRAQ) and proteomic methods, here we identified learning-induced changes in the hippocampal proteome of non-transgenic (NonTg) and 3 × Tg-AD mice, a widely used animal model of AD. We found that expression of 192 proteins was differentially regulated by learning in NonTg mice. Notably, of these 192 proteins, only 28 were also differentially regulated by learning in 3 × Tg-AD mice, whereas the levels of 164 proteins were uniquely changed in NonTg mice but not in 3 × Tg-AD mice. These data suggest that during learning, 3 × Tg-AD mice fail to differentially regulate 164 proteins. Gene ontology and protein interaction analyses indicated that these proteins were overrepresented in RNA processing, specifically RNA transport, splicing and mRNA translation initiation pathways. These findings suggest that mRNA-processing events that take place during learning and memory are significantly altered in 3 × Tg-AD mice.


Assuntos
Doença de Alzheimer/metabolismo , Hipocampo/metabolismo , Aprendizagem , Memória , Mapas de Interação de Proteínas , Doença de Alzheimer/psicologia , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Biossíntese de Proteínas , Proteômica , Splicing de RNA , Transporte de RNA
5.
Am J Transplant ; 16(8): 2293-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26999771

RESUMO

The use of donor extracorporeal membrane oxygenation (ECMO) to improve graft outcomes by some controlled donation after circulatory determination of death (cDCDD) programs raises ethical issues. We reviewed cDCDD protocols using ECMO and the relevant ethics literature to analyze these issues. It is not obvious that ECMO in cDCDD improves graft outcomes. In our opinion, ECMO implemented before death can interfere with end-of-life care and damage bodily integrity. By restoring systemic circulation, ECMO risks invalidating the preceding declaration of death if brain and cardiac perfusion is not adequately excluded because of malfunction or misplacement of the supradiaphragmatic aortic occlusion balloon. The use of ECMO is not compatible with the acronym DCDD because circulation is restored after the determination of death. Because of these deficiencies, we concluded that other techniques are preferable, such as rapid recovery or in situ cold infusion. If ECMO is performed, it requires a specific informed consent and transparency.


Assuntos
Morte Encefálica , Oxigenação por Membrana Extracorpórea/ética , Rejeição de Enxerto/prevenção & controle , Preservação de Órgãos , Transplante de Órgãos , Doadores de Tecidos/provisão & distribuição , Obtenção de Tecidos e Órgãos/métodos , Humanos , Consentimento Livre e Esclarecido
6.
Curr Oncol ; 23(6): e530-e537, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28050141

RESUMO

BACKGROUND: Participant selection for first-in-human (fih) trials involves complex decisions. The trial design makes it unlikely that participants will receive clinically relevant therapeutic benefit, but they are likely to experience risks of various magnitudes and types. The aim of the present paper was to describe and discuss the views of investigators and ethics committee members about the choice of trial participants for fih trials in cancer nanomedicine. METHODS: We drew insights from an exploratory qualitative study involving thematic analysis of 46 in-depth interviews with key stakeholders in Europe and North America involved in fih nanomedicine trials. The present work draws on subset of 21 interviews with investigators and ethics committee members who have either conducted or reviewed a fih cancer nanomedicine trial or are planning one. RESULTS: Investigators and ethics committee members are aware of the ethics standards for recruiting patients with end-stage cancer into fih trials, but they nonetheless question the practice and provide reasons against it. CONCLUSIONS: Although it is a standard and ethically accepted practice to enrol patients with end-stage cancer and no treatment options into fih trials of investigational chemotherapeutic molecules, doing so can threaten the validity and generalizability of the trials, thereby weakening translational research. Another possibility is to stratify and include patients with less advanced disease who demonstrate certain biomarkers or cancer genotypes and who have a disease profile similar to that tested in preclinical studies. The latter approach could be a step toward personalized medical research and targeted drug development. Such a patient selection approach requires multi-stakeholder discussion to reach scientific and ethics consensus.

7.
Sci Eng Ethics ; 22(5): 1431-1446, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26364213

RESUMO

The publish-or-perish paradigm is a prevailing facet of science. We apply game theory to show that, under rather weak assumptions, this publication scenario takes the form of a prisoner's dilemma, which constitutes a substantial obstacle to beneficial delayed publication of more complete results. One way of avoiding this obstacle while allowing researchers to establish priority of discoveries would be an updated "pli cacheté", a sealed envelope concept from the 1700s. We describe institutional rules that could additionally favour high-quality work and publications and provide examples of such policies that are already in place. Our analysis should be extended to other publication scenarios and the role of other stakeholders such as scientific journals or sponsors.


Assuntos
Teoria dos Jogos , Editoração/ética , Dilema do Prisioneiro , Editoração/normas
9.
Clin Genet ; 85(3): 223-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24001330

RESUMO

While there is widespread agreement on the broad aspects of what constitutes a biobank, there is much disagreement regarding the precise definition. This research aimed to describe and analyze the definitions of the term biobank offered by various stakeholders in biobanking. Interviews were conducted with 36 biobanking stakeholders with international experience currently working in Switzerland. The results show that, in addition to the core concepts of biological samples and linked data, the planned use of samples (including sharing) is held to be a key criterion. It also emerges that some researchers avoid the term in order to circumvent certain regulatory guidelines, including informed consent requirements. Developments in the field of biobanking will be complicated if researchers are unaware, or deny that their collection is a biobank. A clear definition of the term is therefore an important step towards fostering collaboration amongst researchers, enabling them to more easily identify potential sources of samples.


Assuntos
Bancos de Espécimes Biológicos/normas , Humanos , Suíça
10.
J Med Ethics ; 35(9): 530-3, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19717690

RESUMO

This paper re-evaluates euthanasia and assisted suicide from the perspective of eudaimonia, the ancient Greek conception of happiness across one's whole life. It is argued that one cannot be said to have fully flourished or had a truly happy life if one's death is preceded by a period of unbearable pain or suffering that one cannot avoid without assistance in ending one's life. While death is to be accepted as part of life, it should not be left to nature to dictate the way we die, and it is fundamentally unjust to grant people liberal latitude in how they live their lives while granting them little control over the conclusion of their life narratives. Three objections to this position are considered and rejected; the paper also offers an explanation of why we think killing can be a benefit. Ultimately, euthanasia may be necessary in some cases in order to achieve eudaimonia.


Assuntos
Atitude Frente a Morte , Eutanásia/ética , Felicidade , Relações Médico-Paciente/ética , Qualidade de Vida/psicologia , Eutanásia/história , Eutanásia/legislação & jurisprudência , História Antiga , Humanos , Filosofia Médica/história
11.
J Med Ethics ; 35(2): 97-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19181881

RESUMO

Kihlbom has recently argued that a system of seeking negatively informed consent might be preferable in some cases to the ubiquitous informed consent model. Although this theory is perhaps not powerful enough to supplant informed consent in most settings, it lends strength to Evans' and Hungin's proposal that it can be ethical to prescribe placebos rather than "active" drugs. This paper presents an argument for using negatively informed consent for the specific purpose of authorising the use of placebos in clinical contexts.


Assuntos
Consentimento Livre e Esclarecido/ética , Relações Médico-Paciente/ética , Placebos/uso terapêutico , Ética Médica , Humanos
12.
Br J Cancer ; 96(4): 567-74, 2007 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-17285137

RESUMO

In a phase II study, 43 renal cell carcinoma patients were treated with individualised doses of ABR-214936; a fusion of a Fab recognising the antigen 5T4, and Staphylococcal enterotoxin A. Drug was given intravenously on 4 consecutive days, treatment was repeated 1 month later. Treatment was associated with moderate fever and nausea, but well tolerated. Of 40 evaluable patients, 28 had disease control at 2 months, and at 4 months, one patient showed partial response (PR) and 16 patients stable disease. Median survival, with minimum follow-up of 26 months was 19.7 months with 13 patients alive to date. Stratification by the Motzer's prognostic criteria highlights prolonged survival compared to published expectation. Patients receiving higher drug exposure had greater disease control and lived almost twice as long as expected, whereas the low-exposure patients survived as expected. Sustained interleukin-2 (IL-2) production after a repeated injection appears to be a biomarker for clinical effect, as the induced-IL-2 level on the day 2 of treatment correlated with survival. The high degree of disease control and the prolonged survival suggest that this treatment can be effective. These findings will be used in the trial design for the next generation of drug, with reduced antigenicity and toxicity.


Assuntos
Antígenos de Neoplasias/imunologia , Carcinoma de Células Renais/tratamento farmacológico , Enterotoxinas/administração & dosagem , Enterotoxinas/imunologia , Neoplasias Renais/tratamento farmacológico , Glicoproteínas de Membrana/administração & dosagem , Glicoproteínas de Membrana/imunologia , Proteínas Recombinantes de Fusão/uso terapêutico , Adulto , Idoso , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/imunologia , Progressão da Doença , Relação Dose-Resposta a Droga , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Enterotoxinas/efeitos adversos , Feminino , Seguimentos , Humanos , Injeções Intravenosas , Interleucina-2/biossíntese , Neoplasias Renais/diagnóstico , Neoplasias Renais/imunologia , Masculino , Glicoproteínas de Membrana/efeitos adversos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/efeitos adversos , Taxa de Sobrevida , Resultado do Tratamento
13.
Biochim Biophys Acta ; 1524(2-3): 238-46, 2000 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11113573

RESUMO

The oncofoetal antigen 5T4 is a 72 kDa glycoprotein expressed at the cell surface. It is defined by a monoclonal antibody, mAb5T4, that recognises a conformational extracellular epitope in the molecule. Overexpression of 5T4 antigen by tumours of several types has been linked with disease progression and poor clinical outcome. Its restricted expression in non-malignant tissue makes 5T4 antigen a suitable target for the development of antibody directed therapies. The use of murine monoclonal antibodies for targeted therapy allows the tumour specific delivery of therapeutic agents. However, their use has several drawbacks, including a strong human anti-mouse immune (HAMA) response and limited tumour penetration due to the size of the molecules. The use of antibody fragments leads to improved targeting, pharmacokinetics and a reduced HAMA. A single chain antibody (scFv) comprising the variable regions of the mAb5T4 heavy and light chains has been expressed in Escherichia coli. The addition of a eukaryotic leader sequence allowed production in mammalian cells. The two 5T4 single chain antibodies, scFv5T4WT19 and LscFv5T4, described the same pattern of 5T4 antigen expression as mAb5T4 in normal human placenta and by FACS. Construction of a 5T4 extracellular domain-IgGFc fusion protein and its expression in COS-7 cells allowed the relative affinities of the antibodies to be compared by ELISA and measured in real time using a biosensor based assay. MAb5T4 has a high affinity, K(D)=1.8x10(-11) M, as did both single chain antibodies, scFv5T4WT19 K(D)=2.3x10(-9) M and LscFv5T4 K(D)=7.9x10(-10) M. The small size of this 5T4 specific scFv should allow construction of fusion proteins with a range of biological response modifiers to be prepared whilst retaining the improved pharmacokinetic properties of scFvs.


Assuntos
Anticorpos Monoclonais/imunologia , Fragmentos de Imunoglobulinas/isolamento & purificação , Região Variável de Imunoglobulina/isolamento & purificação , Glicoproteínas de Membrana/imunologia , Sequência de Aminoácidos , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/genética , Antígenos de Neoplasias/imunologia , Sequência de Bases , Clonagem Molecular , Ensaio de Imunoadsorção Enzimática , Feminino , Terapia Genética , Humanos , Fragmentos de Imunoglobulinas/genética , Fragmentos de Imunoglobulinas/imunologia , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Imuno-Histoquímica , Glicoproteínas de Membrana/análise , Dados de Sequência Molecular , Mutação , Placenta/imunologia , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Neoplasias Gástricas/imunologia , Ressonância de Plasmônio de Superfície
16.
Immunology ; 100(4): 510-8, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10929079

RESUMO

The delivery of antigens to mucosal-associated lymphoid tissues in paediatric and immunocompromised populations by safe, non-invasive vectors, such as commensal lactobacilli, represents a crucial improvement to prevailing vaccination options. In this report, we describe the oral and nasal immunization of mice with vaccines constructed through an original system for heterologous gene expression in Lactobacillus in which the 50 000-molecular weight (MW) fragment C of tetanus toxin (TTFC) is expressed either as an intracellular or a surface-exposed protein. Our data indicate that L. plantarum is more effective in this respect than L. casei and that, under the experimental conditions investigated, delivery of TTFC expressed as an intracellular antigen is more effective than cell-surface expression. Immunization of mice with live recombinant lactobacilli induced significant levels of circulating TTFC-specific immunoglobulin G (IgG) following nasal or oral delivery of vaccine strains. In addition, following nasal delivery, secretory immunoglobulin A (sIgA) was induced in bronchoalveolar lavage fluids, as were antigen-specific antibody-secreting cells and antigen-specific T-cell activation in draining lymph nodes, substantiating their potential for safe mucosal delivery of paediatric vaccines.


Assuntos
Imunoglobulina G/biossíntese , Lactobacillus/genética , Linfonodos/imunologia , Fragmentos de Peptídeos/imunologia , Toxina Tetânica/imunologia , Vacinas de DNA/imunologia , Animais , Ensaio de Imunoadsorção Enzimática , Imunidade nas Mucosas , Imunização/métodos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL
17.
Vaccine ; 17(17): 2117-28, 1999 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-10367944

RESUMO

Lactobacillus strains possess properties that make them attractive candidates as vehicles for oral administration of therapeutics. In this report we describe the construction and analysis of recombinant Lactobacillus casei applicable in oral vaccination against an infectious disease (tetanus) and in oral tolerance induction for intervention in an autoimmune disease, multiple sclerosis. Recombinant L. casei which express surface-anchored tetanus toxin fragment C (TTFC) were generated. Quantitative analysis by flow cytometry demonstrated a high level of cell wall-bound expression of TTFC and immunogenicity was demonstrated by parenteral immunization with whole cell extracts of the recombinants. A series of expression vectors was constructed to secrete human myelin basic protein (hMBP) or hMBP as a fusion protein with beta-glucuronidase from Escherichia coli. These heterologous products produced by L. casei were detected in the growth medium and parenteral immunization with this medium evoked antibodies against hMBP, confirming that secretion indeed had occurred. Based on the different localization of the heterologous proteins, lactobacilli expressing surface-anchored TTFC are ideally suited for the induction of antibody responses, whereas lactobacilli that secrete myelin proteins can be used for the induction of peripheral T-cell tolerance. In conclusion, the specific technology described here allows the construction of a wide array of safe live recombinant lactobacilli which may prove to be useful in oral intervention strategies for the prevention of infectious diseases or treatment of autoimmune diseases.


Assuntos
Vacinas Bacterianas/imunologia , Tolerância Imunológica , Lacticaseibacillus casei/genética , Esclerose Múltipla/imunologia , Proteína Básica da Mielina/imunologia , Fragmentos de Peptídeos/imunologia , Toxina Tetânica/imunologia , Tétano/prevenção & controle , Administração Oral , Animais , Vacinas Bacterianas/biossíntese , Vacinas Bacterianas/genética , Bovinos , Citometria de Fluxo , Vetores Genéticos , Cobaias , Humanos , Imuno-Histoquímica , Lacticaseibacillus casei/metabolismo , Camundongos , Esclerose Múltipla/terapia , Proteína Básica da Mielina/biossíntese , Proteína Básica da Mielina/genética , Proteína Básica da Mielina/metabolismo , Fragmentos de Peptídeos/biossíntese , Fragmentos de Peptídeos/genética , Coelhos , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Tétano/imunologia , Toxina Tetânica/biossíntese , Toxina Tetânica/genética
18.
Fam Process ; 37(2): 167-87, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9693948

RESUMO

Much contemporary family therapy theory and practice takes into account clients' cognitive constructions of their family problems. Recent calls for therapists to elicit and work with clients' causal explanations and narratives parallel accumulating evidence in the social-clinical literature about the predictive importance of attributions in family relationships. In this article, we introduce the Constructions of Problems Scale (CPS), provide preliminary evidence of its reliability and validity, and suggest ways in which it can be used clinically to reveal new areas for questioning and to generate new ideas. The CPS is a brief questionnaire that can be used to create a profile of each individual family member's private constructions. To complete the CPS, each family member writes a free-form narrative of the presenting problem and then rates his or her perceptions of the contributing causes. The CPS profiles can be used to compare the perspectives of different family members and to assess cognitive constructions at different points in treatment. We discuss its potential for these and other clinical uses.


Assuntos
Relações Familiares , Terapia Familiar/métodos , Conhecimentos, Atitudes e Prática em Saúde , Determinação da Personalidade , Adulto , Feminino , Humanos , Relações Interpessoais , Masculino , Relações Pais-Filho , Poder Familiar/psicologia , Reprodutibilidade dos Testes , Fatores Socioeconômicos , Inquéritos e Questionários
19.
Immunol Lett ; 57(1-3): 15-7, 1997 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-9232419

RESUMO

AIMS: To identify peptides that mimic (mimotopesi conformational and protective epitopes of RSV fusion protein and to assess their efficacy as immunogens and potential vaccines. MATERIAL AND METHODS: An 8-mer solid-phase (TG resin) library was screened with a neutralising and protective RSV fusion protein specific monoclonal antibodies (Mab-19). After selection of positive beads, reactive sequences were identified by microsequencing and 8-mer peptides were synthesised. Improvement of binding was analysed by amino acid replacement using the SPOTs method. RESULTS: Mabs were not able to bind to the free and soluble peptides, nor did these peptides induce anti-RSV specific antibodies. However, several peptides re-synthesised on a TG resin (to produce de-protected 8-mer peptides linked to the resin) or as SPOTs reacted specifically. Therefore it was critical to be able to reproduce this conformation in order to use these mimotopes as immunogens and potential vaccines. Using C-terminal constrained versions of the mimotopes, strong binding of one of the Mabs to the peptides was demonstrated by surface-plasmon resonance. Immunisation of Balb/c mice with these peptide-mimics produced anti-sera that: (1) reacted specifically with RSV; (2) inhibited the binding of the Mab to the virus; (3) neutralised RSV in vitro with high titres (range: 80-640); and (4) reduce significantly the viral load in the lungs of mice challenged with RSV (P < 0.01). CONCLUSIONS: This report demonstrates for the first time that: (1) a protective epitope of the conserved RSV fusion protein can be mimicked by synthetic peptides; and (2) immunisations with these mimotopes induced specific anti-RSV neutralising antibodies and reduced viral load in vivo. These results represent a novel concept for the development of a vaccine against RSV.


Assuntos
Epitopos/imunologia , Proteína HN , Peptídeos/imunologia , Vírus Sinciciais Respiratórios/imunologia , Proteínas Virais/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Mimetismo Molecular , Testes de Neutralização , Peptídeos/síntese química , Vacinação , Proteínas do Envelope Viral , Proteínas Virais/síntese química
20.
Int J Biochem Cell Biol ; 29(1): 201-10, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9076955

RESUMO

The lack of scarring and fibrosis in healing fetal skin wounds may relate to a prolonged presence of hyaluronan (HA). It has been suggested that fetal wounds may lack hyaluronidase, but the hyaluronidase levels in fetal wounds remain unknown. The size of HA influences its biological action, especially in relation to angiogenesis, which is also reduced in fetal wound healing. The present study determined the levels and size of HA, as well as hyaluronidase levels, in fetal and adult lamb wounds. Wire mesh cylinders, or polyvinyl acetate sponges, were placed subcutaneously in fetal lambs at 75, 100 or 120 days gestation. Wound fluid and wound tissue were harvested 3, 7 or 14 days later. Samples were digested with papain and both HA and hyaluronidase activity were determined in a competitive ELISA assay. Size distribution of HA was estimated using a Sephacryl S1000 column and fractions were collected for HA determination. Adult wound fluid HA remained low (4-5 micrograms/ml) over the 14 days. Fetal fluids were similar on day 3, but increased to 15-25 micrograms/ml by day 7. In 75/100-day wounds, HA remained elevated at 14 days, but in 120-day fluids decreased to levels similar to adult fluid. The HA in all fluids was polydisperse with a main peak at 200 kDa. Hyaluronidase levels were detected in all samples, reaching a peak 7 days post-wounding. In adult wound fluids hyaluronidase was much higher than the fetal wound fluids. These data suggest that lower hyaluronidase levels in fetal wounds may underlie the different pattern of HA deposition seen in fetal wounds.


Assuntos
Feto/fisiopatologia , Ácido Hialurônico/metabolismo , Hialuronoglucosaminidase/metabolismo , Lesões Pré-Natais , Cicatrização/fisiologia , Líquido Amniótico/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Fibrose , Idade Gestacional , Ácido Hialurônico/urina , Hialuronoglucosaminidase/urina , Gravidez , Regeneração/fisiologia , Ovinos , Distribuição Tecidual
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