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Existing participatory research approaches have failed to identify innovative methods that overcome the persistent barriers to adolescent sexual and reproductive health service demand and access. Increasingly, programmers have turned to human-centered design (HCD), a problem-solving process that centers the needs, perspectives, and experiences of people, when developing solutions to complex SRH challenges. This article describes the application of a youth-engaged version of HCD as part of Adolescents 360, a transdisciplinary initiative to increase 15- to 19-year-old girls' use of modern contraception in Nigeria, Ethiopia, and Tanzania. Youth-adult design teams (including 111 "youth designers" trained in HCD methods) undertook formative research to inform the design and implementation of interventions. We reflect on the practical implications of using instrumental strategies of HCD with a youth-led participatory approach. Our experience indicates that (1) engaging youth as project partners in transdisciplinary teams requires planned and dedicated financial and human resources; (2) involving youth as action researchers can help identify opportunities to improve program empathy and responsiveness; (3) it is difficult to recruit "extreme users" as project partners because of the high competencies needed in HCD; (4) centering empathy and employing design standards during prototyping can drive decision-making and resolve questions raised by conflicting evidence claims in existing bodies of literature; and (5) testing tangible services and products in real-world settings continues long after the intervention design phase. Youth-adult partnership should continue throughout this iterative and adaptive phase to ensure that the adolescent experience of the intervention remains at the core of intervention delivery.
Assuntos
Serviços de Saúde Reprodutiva , Saúde Sexual , Adolescente , Adulto , Feminino , Pesquisa sobre Serviços de Saúde , Humanos , Saúde Reprodutiva , Comportamento Sexual , Adulto JovemRESUMO
BACKGROUND: Skilled birth attendance, institutional deliveries, and provision of quality, respectful care are key practices to improve maternal and neonatal health outcomes. In Mozambique, the government has prioritized improved service delivery and demand for these practices, alongside "humanization of the birth process." An intervention implemented in Nampula province beginning in 2009 saw marked improvement in institutional delivery rates. This study uses a sequential explanatory mixed methods case study design to explore the contextual factors that may have contributed to the observed increase in institutional deliveries. METHODS: A descriptive time series analysis was conducted using clinic register data from 2009 to 2014 to assess institutional delivery coverage rates in two primary health care facilities, in two districts of Nampula province. Site selection was based on facilities exhibiting an initial increase in institutional deliveries from 2009 to 2011, similarity of health system attributes, and accessibility for study participation. Using a modified Delphi technique, two expert panels-each composed of ten stakeholders familiar with maternal health implementation at facility, district, provincial, and national levels-were convened to formulate the "story" of the implementation and to identify contextual factors to use in developing semi-structured interview guides. Thirty-four key informant interviews with facility MCH nurses, facility managers, traditional birth attendants, community leaders, and beneficiaries were then conducted and analyzed using the Consolidated Framework for Implementation Research through inductive and deductive coding. RESULTS: The two sites' skilled birth attendance coverage of estimated live births reached 80 and 100%, respectively. Eight contextual and human factors were found as dominant themes. Though both sites achieved increases, implementation context differed significantly with compelling examples of both respectful and disrespectful care. In one site, facility and community actors worked together as complementary systems to sustain improved care and institutional deliveries. In the other, community actors sustained implementation and institutional deliveries largely in absence of health system counterparts. CONCLUSION: Findings support global health recommendations for combined health system and community interventions for improved MNH outcomes including delivery of respectful care, and further suggest the capacity of communities to act as systems both in partnership to and independent of the formal health system.
Assuntos
Parto Obstétrico , Instalações de Saúde , Serviços de Saúde Materna/organização & administração , Tocologia , Feminino , Saúde Global , Humanos , Moçambique , Parto , GravidezRESUMO
Early temperamental sensitivity may form the basis for the later development of socioemotional maladjustment. In particular, temperamental negative affect places children at risk for the development of anxiety. However, not all children who show negative affect go on to develop anxiety or extreme social withdrawal. Recent research indicates that reactive control, in the form of attention to threat, may serve as a bridge between early temperament and the development of later social difficulties. In addition, variation in effortful control may also modulate this trajectory. Children (mean age=5.57 years) were assessed for attention bias to threatening and pleasant faces using a dot-probe paradigm. Attention bias to threatening (but not happy) faces moderated the direct positive relation between negative affect and social withdrawal. Children with threat biases showed a significant link between negative affect and social withdrawal, whereas children who avoided threat did not. In contrast, effortful control did not moderate the relation between negative affect and social withdrawal. Rather, there was a direct negative relation between effortful control and social withdrawal. The findings from this short report indicate that the relations among temperament, attention bias, and social withdrawal appears early in life and point to early emerging specificity in reactive and regulatory functioning.
Assuntos
Afeto/fisiologia , Ansiedade/psicologia , Atenção/fisiologia , Comportamento Social , Criança , Pré-Escolar , Emoções/fisiologia , Feminino , Humanos , Masculino , TemperamentoRESUMO
Heparan sulfate (HS) is a component of cell surface and extracellular matrix proteoglycans that regulates numerous signaling pathways by binding and activating multiple growth factors and chemokines. The amount and pattern of HS sulfation are key determinants for the assembly of the trimolecular, HS-growth factor-receptor, signaling complex. Here we demonstrate that HS 6-O-sulfotransferases 1 and 2 (HS6ST-1 and HS6ST-2), which perform sulfation at 6-O position in glucosamine in HS, impact ovarian cancer angiogenesis through the HS-dependent HB-EGF/EGFR axis that subsequently modulates the expression of multiple angiogenic cytokines. Down-regulation of HS6ST-1 or HS6ST-2 in human ovarian cancer cell lines results in 30-50% reduction in glucosamine 6-O-sulfate levels in HS, impairing HB-EGF-dependent EGFR signaling and diminishing FGF2, IL-6, and IL-8 mRNA and protein levels in cancer cells. These cancer cell-related changes reduce endothelial cell signaling and tubule formation in vitro. In vivo, the development of subcutaneous tumor nodules with reduced 6-O-sulfation is significantly delayed at the initial stages of tumor establishment with further reduction in angiogenesis occurring throughout tumor growth. Our results show that in addition to the critical role that 6-O-sulfate moieties play in angiogenic cytokine activation, HS 6-O-sulfation level, determined by the expression of HS6ST isoforms in ovarian cancer cells, is a major regulator of angiogenic program in ovarian cancer cells impacting HB-EGF signaling and subsequent expression of angiogenic cytokines by cancer cells.
Assuntos
Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Neoplasias Ovarianas/metabolismo , Sulfotransferases/metabolismo , Animais , Linhagem Celular Tumoral , Meios de Cultivo Condicionados/química , Citocinas/metabolismo , Dissacarídeos/metabolismo , Feminino , Fator 2 de Crescimento de Fibroblastos/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Glucosamina/metabolismo , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Transplante de Neoplasias , Neovascularização Patológica , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Transdução de SinaisRESUMO
Late outgrowth endothelial cells (OECs) that originate from peripheral blood mononuclear cells ex vivo have phenotypic and functional properties of mature endothelial cells. Given the potential therapeutic applications of OECs, understanding their biology is crucial. We have identified two distinct OEC populations based on differential expression of the cell surface marker CD34. OEC colonies lacked CD34 expression (CD34-), expressed CD34 in the majority of cells (CD34+), or showed a mixed expression pattern within a colony (CD34+/-). CD34+ and CD34- OECs were negative for hematopoietic cell marker CD45 and expressed the endothelial cell surface markers CD31, CD146, CD105, and VEGFR-2. Functionally CD34- and CD34+ OECs exhibited strikingly distinct behaviors. CD34- OECs, unlike CD34+ OECs, were capable of sprouting, formed tubes, and responded to angiogenic growth factors in vitro. In vivo, CD34- OECs formed endothelial tubes, while CD34+ OECs, despite being unable to form tubes, promoted infiltration of murine vasculature. Global gene expression profiling in CD34- and CD34+ OECs identified functional importance of the MMP-1/PAR-1 pathway in CD34- OECs. MMP-1 stimulated the expression of VEGFR-2, neuropilin-1, neuropilin-2, and CXCR4 and activated ERK1/2, whereas down-regulation of PAR-1 in CD34- OECs resulted in impaired angiogenic responses in vitro and reduced VEGFR-2 levels. In contrast, the CD34+ OEC colonies expressed high levels of the progenitor cell marker ALDH, which was absent in CD34- OECs. In summary, we show that OECs can be classified into functionally mature endothelial cells (CD34- OECs) that depend on the MMP-1/PAR-1 pathway and progenitor-like angiogenesis-promoting cells (CD34+ OECs).
Assuntos
Antígenos CD34/metabolismo , Separação Celular/métodos , Células Endoteliais/citologia , Células Endoteliais/fisiologia , Neovascularização Fisiológica/fisiologia , Animais , Movimento Celular , Colágeno , Primers do DNA/genética , Combinação de Medicamentos , Células Endoteliais/metabolismo , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Imunofluorescência , Perfilação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana , Humanos , Immunoblotting , Laminina , Metaloproteinase 1 da Matriz/metabolismo , Camundongos , Análise em Microsséries , Proteoglicanas , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismoRESUMO
Stimulation of the intermediate and deep layers of superior colliculus (DLSC) in rodents evokes both orienting/pursuit (approach) and avoidance/flight (defense) responses (Dean et al., 1989). These two classes of response are subserved by distinct output projections associated with lateral (approach) and medial (defense) DLSC (Comoli et al., 2012). In non-human primates, DLSC has been examined only with respect to orienting/approach behaviors, especially eye movements, and defense-like behaviors have not been reported. Here we examined the profile of behavioral responses evoked by activation of DLSC by unilateral intracerebral infusions of the GABA(A) receptor antagonist, bicuculline methiodide (BIC), in nine freely moving macaques. Across animals, the most consistently evoked behavior was cowering (all animals), followed by increased vocalization and escape-like behaviors (seven animals), and attack of objects (three animals). The effects of BIC were dose-dependent within the range 2.5-14 nmol (threshold dose of 4.6 nmol). The behaviors and their latencies to onset did not vary across different infusion sites within DLSC. Cowering and escape-like behaviors resembled the defense-like responses reported after DLSC stimulation in rats, but in the macaques these responses were evoked from both medial and lateral sites within DLSC. Our findings are unexpected in the context of an earlier theoretical perspective (Dean et al., 1989) that emphasized a preferential role of the primate DLSC for approach rather than defensive responses. Our data provide the first evidence for induction of defense-like behaviors by activation of DLSC in monkeys, suggesting that the role of DLSC in responding to threats is conserved across species.
Assuntos
Comportamento Animal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Colículos Superiores/efeitos dos fármacos , Vocalização Animal/efeitos dos fármacos , Animais , Comportamento Animal/fisiologia , Bicuculina/farmacologia , Relação Dose-Resposta a Droga , Feminino , Antagonistas de Receptores de GABA-A/farmacologia , Macaca mulatta , Macaca nemestrina , Masculino , Neurônios/fisiologia , Colículos Superiores/fisiologia , Vocalização Animal/fisiologiaRESUMO
Why are some young children consistently willing to believe what they are told even when it conflicts with first-hand experience? In this study, we investigated the possibility that this deference reflects an inability to inhibit a prepotent response. Over the course of several trials, 2.5- to 3.5-year-olds (N = 58) heard an adult contradict their report of a simple event they had both witnessed, and children were asked to resolve this discrepancy. Those who repeatedly deferred to the adult's misleading testimony had more difficulty on an inhibitory control task involving spatial conflict than those who responded more skeptically. These results suggest that responding skeptically to testimony that conflicts with first-hand experience may be challenging for some young children because it requires inhibiting a normally appropriate bias to believe testimony.
Assuntos
Cultura , Inibição Psicológica , Percepção Espacial/fisiologia , Confiança , Desenvolvimento Infantil , Pré-Escolar , Conflito Psicológico , Feminino , Humanos , Masculino , Teoria da MenteRESUMO
The UK has fallen from fourth to 10th place in the global ranking for clinical trial activities in the past 6 years. Due to the limited capacity of the clinical trial pharmacy workforce and delays in providing pharmacy approvals, pharmacy has been identified as one of the constraining services that delays the set-up and delivery of clinical trials. To tackle this problem, we developed a single pharmacy review process for multicentre trials across Greater Manchester (GM) and tested its feasibility and implementation in our region. A survey completed by each GM Trust suggests that this harmonised pharmacy review process for multicentre studies would expedite trial set-up time at each pharmacy site and standardise the pharmacy review process in GM. We therefore believe that this harmonised review process could potentially reduce pharmacy set-up time and reposition the UK in the global market for clinical trials.
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Fibroblast growth factor 2 (FGF2) and vascular endothelial growth factor 165 (VEGF(165)) are potent pro-angiogenic growth factors that play a pivotal role in tumor angiogenesis. The activity of these growth factors is regulated by heparan sulfate (HS), which is essential for the formation of FGF2/FGF receptor (FGFR) and VEGF(165)/VEGF receptor signaling complexes. However, the structural characteristics of HS that determine activation or inhibition of such complexes are only partially defined. Here we show that ovarian tumor endothelium displays high levels of HS sequences that harbor glucosamine 6-O-sulfates when compared with normal ovarian vasculature where these sequences are also detected in perivascular area. Reduced HS 6-O-sulfotransferase 1 (HS6ST-1) or 6-O-sulfotransferase 2 (HS6ST-2) expression in endothelial cells impacts upon the prevalence of HS 6-O-sulfate moieties in HS sequences, which consist of repeating short, highly sulfated S domains interspersed by transitional N-acetylated/N-sulfated domains. 1-40% reduction in 6-O-sulfates significantly compromises FGF2- and VEGF(165)-induced endothelial cell sprouting and tube formation in vitro and FGF2-dependent angiogenesis in vivo. Moreover, HS on wild-type neighboring endothelial or smooth muscle cells fails to restore endothelial cell sprouting and tube formation. The affinity of FGF2 for HS with reduced 6-O-sulfation is preserved, although FGFR1 activation is inhibited correlating with reduced receptor internalization. These data show that 6-O-sulfate moieties in endothelial HS are of major importance in regulating FGF2- and VEGF(165)-dependent endothelial cell functions in vitro and in vivo and highlight HS6ST-1 and HS6ST-2 as potential targets of novel antiangiogenic agents.
Assuntos
Fator 2 de Crescimento de Fibroblastos/metabolismo , Heparitina Sulfato/biossíntese , Células Endoteliais da Veia Umbilical Humana/metabolismo , Proteínas de Neoplasias/metabolismo , Neovascularização Patológica/metabolismo , Neoplasias Ovarianas/irrigação sanguínea , Neoplasias Ovarianas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Células Cultivadas , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Fator 2 de Crescimento de Fibroblastos/genética , Heparitina Sulfato/genética , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Proteínas de Neoplasias/genética , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Sulfotransferases/genética , Sulfotransferases/metabolismo , Fator A de Crescimento do Endotélio Vascular/genéticaRESUMO
Electroencephalogram (EEG) asymmetry in the alpha frequency band has been implicated in emotion processing and broad approach-withdrawal motivation systems. Questions remain regarding the cognitive mechanisms that may help elucidate the observed links between EEG asymmetry and patterns of socioemotional functioning. The current study observed frontal EEG asymmetry patterns at rest and under social threat among young adults (N=45, M=21.1 years). Asymmetries were, in turn, associated with performance on an emotion-face dot-probe attention bias task. Attention biases to threat have been implicated as potential causal mechanisms in anxiety and social withdrawal. Frontal EEG asymmetry at baseline did not predict attention bias patterns to angry or happy faces. However, increases in right frontal alpha asymmetry from baseline to the stressful speech condition were associated with vigilance to angry faces and avoidance of happy faces. The findings may reflect individual differences in the pattern of response (approach or withdrawal) with the introduction of a mild stressor. Comparison analyses with frontal beta asymmetry and parietal alpha asymmetry did not find similar patterns. Thus, the data may reflect the unique role of frontal regions, particularly the dorsolateral prefrontal cortex, in cognitive control and threat detection, coupled with ruminative processes associated with alpha activity.
Assuntos
Ritmo alfa , Atenção/fisiologia , Córtex Cerebral/fisiologia , Adulto , Comportamento de Escolha/fisiologia , Eletroencefalografia , Feminino , Humanos , Masculino , Estresse Psicológico , Adulto JovemRESUMO
Socially withdrawn individuals display solitary behavior across wide contexts with both unfamiliar and familiar peers. This tendency to withdraw may be driven by either past or anticipated negative social encounters. In addition, socially withdrawn individuals often exhibit right frontal electroencephalogram (EEG) asymmetry at baseline and when under stress. In the current study we examined shifts in frontal EEG activity in young adults (N=41) at baseline, as they viewed either an anxiety-provoking or a benign speech video, and as they subsequently prepared for their own speech. Results indicated that right frontal EEG activity increased, relative to the left, only for socially withdrawn participants exposed to the anxious video. These results suggest that contextual affective cues may prime an individual's response to stress, particularly if they illustrate or substantiate an anticipated negative event.
Assuntos
Sinais (Psicologia) , Lateralidade Funcional/fisiologia , Transtornos Fóbicos/fisiopatologia , Fala/fisiologia , Eletroencefalografia , Feminino , Lobo Frontal/fisiologia , Lobo Frontal/fisiopatologia , Humanos , Masculino , Determinação da Personalidade , Adulto JovemRESUMO
Background: Adolescents 360 (A360) implements the Smart Start (SS) programme through Ethiopia's Health Extension Programme (HEP). SS is premised on financial planning as an entry point to discuss family planning (FP) with newly married couples and central to its delivery are the health extension workers (HEW). This article evaluates the A360 experience and learning from the process evaluation implemented by Itad to understand contextual barriers and enablers from the perspective of the HEW. Methods: A purposive sampling strategy was employed whereby 27 key stakeholders were identified from Oromia, Addis Ababa and Amhara, based on exposure to the SS programme. Findings from the action research were shared with A360 through a one day sounding workshop. Results: Findings revealed that many local government and communal respondents do not view adolescent pregnancy as a problem, unless out of wedlock, and adolescent pregnancy is closely linked to early marriage. As a result, some providers, including HEWs, acknowledged that married adolescent girls were previously 'neglected' by them, while husbands indicated that they had not previously been included in FP counselling. Findings also revealed some challenges with SS implementation as HEWs were 'deprioritizing' the intervention and many HEWs had been in situ for several years and were overworked and frustrated. Against this backdrop, A360 was viewed as adding to the HEW workload. While the programme design was focused on adolescent users, there was increasing recognition that HEWs also needed to be at the centre of solution design. Conclusions: Despite challenges associated with the HEP, Ethiopia FP2020 plans to support the 'next generation' of HEWs, including a focus on adolescents and youth. To gain deeper insight and put the HEW at the centre of design, A360 will continue to work with the process evaluation to understand contextual barriers and enablers from the perspective of the HEW.
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This article analyzes the relevance of the comprehensive definition of sexual and reproductive health and rights (SRHR) to adolescents and identifies adolescent-specific implications for the implementation of an essential package of SRHR interventions. The delivery of a comprehensive approach to SRHR targeting adolescents is underpinned by five principles-equity, quality, accountability, multisectorality, and meaningful engagement. All SRHR interventions included in the package are relevant to adolescents, given the diversity of adolescents' SRHR needs and considering their specific attributes, circumstances, and experiences. Ensuring that this package is available, accessible, and acceptable to adolescents requires an approach that looks at adolescents as being biologically and socially distinct from other age groups and acknowledges that they face some specific barriers when accessing SRHR services. This article provides cross-cutting strategies for the implementation of a comprehensive approach to SRHR for adolescents and specific considerations in delivering each intervention in the package of essential SRHR interventions. To further implement the International Conference on Population and Development Programme of Action, a prerequisite for achieving the Sustainable Development Goals, SRHR interventions must be adolescent responsive, delivered through multiple platforms, leveraging multisectoral collaboration, and strengthening accountability and participation.
Assuntos
Saúde do Adolescente/tendências , Direitos Civis/tendências , Saúde Reprodutiva/tendências , Comportamento Sexual/estatística & dados numéricos , Saúde Sexual/tendências , Aborto Induzido/estatística & dados numéricos , Adolescente , Feminino , Humanos , Masculino , Gravidez , Gravidez na Adolescência/estatística & dados numéricos , Delitos Sexuais/estatística & dados numéricos , Estados Unidos/epidemiologiaRESUMO
The 1994 International Conference on Population and Development established a basis for the advancement of adolescent sexual and reproductive health and rights (ASRHR) that endures today. Twenty-five years later, our vision for the future warrants reflection based on a clear understanding of the opportunities and challenges before us. Inclusion of adolescents on global, regional, and national agendas; increased investment in ASRHR policies and programs; renewed commitments to universal health coverage; increased school enrollment; and advances in technology are all critical opportunities we can and must leverage to catalyze progress for adolescents. At the same time, a range of significant challenges remain, have newly emerged, or can be seen on the horizon, including persistent denial of adolescent sexuality; entrenched gender inequality; resistance to meaningfully engaging adolescents and young people in political and programmatic processes; weak systems, integration, and multisectoral coordination; changes in population dynamics; humanitarian and climate crises; and changes in family and community structures. To achieve as much progress toward our vision for ASRHR as possible, the global ASRHR community must take strategic and specific steps in the next 10 years within five areas for action: (1) mobilize and make full use of political and social support for ASRHR policies and programs; (2) increase and make effective use of external and domestic funding for ASRHR; (3) develop, communicate, apply, and monitor enabling and protective laws and policies for ASRHR; (4) use and improve available ASRHR data and evidence to strengthen advocacy, policies, and programs; and (5) manage the implementation of ASRHR strategies at scale with quality and equity.
Assuntos
Saúde do Adolescente/tendências , Direitos Civis/tendências , Saúde Reprodutiva/tendências , Comportamento Sexual/estatística & dados numéricos , Saúde Sexual/tendências , Aborto Induzido/estatística & dados numéricos , Adolescente , Feminino , Humanos , Masculino , Gravidez , Gravidez na Adolescência/estatística & dados numéricos , Serviços de Saúde Reprodutiva/tendências , Delitos Sexuais/estatística & dados numéricos , Fatores Socioeconômicos , Estados Unidos/epidemiologiaRESUMO
The antitumour effect of thymidylate synthase inhibitors such as raltitrexed (RTX) may be reversed by salvage of thymidine (Thd). Since thymidine phosphorylase (TP) depletes Thd, the potential for tumour-selective depletion of Thd using antibody-mediated delivery of TP to tumours was investigated. In vitro studies demonstrated that 25 x 10(-3) units/ml TP depleted extracellular Thd (3 microM) and restored sensitivity to the growth inhibitory effects of RTX in Lovo and HT29 cell lines. Thymidine concentrations in xenograft tumours were inversely proportional to the activity of TP in the tumour, and the presence of a subcutaneous Lovo xenograft reduced plasma Thd concentrations from 0.92 +/- 0.07 to 0.37 +/- 0.04 microM. Intravenous administration of native TP enzyme depleted plasma Thd to 5 nM, but following rapid elimination of TP, plasma Thd returned to pretreatment values. There was no effect on tumour TP or Thd. Conjugation of TP to the A5B7 F(ab)2 antibody fragment, which targets carcinoembryonic antigen (CEA) expressed on colorectal cell-lines such as Lovo, did result in selective accumulation of TP in the tumour. However, there was no tumour-selective depletion of Thd and there did not appear to be any potential benefit of combining antibody-targeted TP with RTX.
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Quinazolinas/uso terapêutico , Tiofenos/uso terapêutico , Timidina Fosforilase/metabolismo , Timidina/metabolismo , Timidilato Sintase/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Antimetabólitos Antineoplásicos/farmacologia , Antimetabólitos Antineoplásicos/uso terapêutico , Antígeno Carcinoembrionário/imunologia , Antígeno Carcinoembrionário/metabolismo , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Células HT29 , Humanos , Fragmentos Fab das Imunoglobulinas/imunologia , Fragmentos Fab das Imunoglobulinas/metabolismo , Injeções Intravenosas , Camundongos , Camundongos Nus , Quinazolinas/farmacologia , Reprodutibilidade dos Testes , Tiofenos/farmacologia , Timidina Fosforilase/administração & dosagem , Timidina Fosforilase/imunologia , Timidilato Sintase/metabolismoRESUMO
Heparan sulphate (HS), a ubiquitously expressed glycosaminoglycan (GAG), regulates multiple cellular functions by mediating interactions between numerous growth factors and their cell surface cognate receptors. However, the structural specificity of HS in these interactions remains largely undefined. Here, we used completely synthetic, structurally defined, alternating N-sulfated glucosamine (NS) and 2-O-sulfated iduronate (IS) residues to generate dodecasaccharides ([NSIS]6) that contained no, one or six glucosamine 6-O-sulfates (6S). The aim was to address how 6S contributes to the potential of defined HS dodecasaccharides to inhibit the angiogenic growth factors FGF2 and VEGF165, in vitro and in vivo. We show that the addition of a single 6S at the non-reducing end of [NSIS]6, i.e. [NSIS6S]-[NSIS]5, significantly augments the inhibition of FGF2-dependent endothelial cell proliferation, migration and sprouting in vitro when compared to the non-6S variant. In contrast, the fully 6-O-sulfated dodecasaccharide, [NSIS6S]6, is not a potent inhibitor of FGF2. Addition of a single 6S did not significantly improve inhibitory properties of [NSIS]6 when tested against VEGF165-dependent endothelial cell functions.In vivo, [NSIS6S]-[NSIS]5 blocked FGF2-dependent blood vessel formation without affecting tumor growth. Reduction of non-FGF2-dependent ovarian tumor growth occurred when [NSIS6S]-[NSIS]5 was combined with cisplatin. The degree of inhibition by [NSIS6S]-[NSIS]5 in combination with cisplatin in vivo equated with that induced by bevacizumab and sunitinib when administered with cisplatin. Evaluation of post-treatment vasculature revealed that [NSIS6S]-[NSIS]5 treatment had the greatest impact on tumor blood vessel size and lumen formation. Our data for the first time demonstrate that synthetic, structurally defined oligosaccharides have potential to be developed as active anti-angiogenic agents that sensitize tumors to chemotherapeutic agents.
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Inibidores da Angiogênese/síntese química , Cisplatino/uso terapêutico , Glucosamina/análogos & derivados , Oligossacarídeos/síntese química , Neoplasias Ovarianas/tratamento farmacológico , Inibidores da Angiogênese/uso terapêutico , Inibidores da Angiogênese/toxicidade , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cisplatino/toxicidade , Quimioterapia Combinada , Feminino , Fator 2 de Crescimento de Fibroblastos/antagonistas & inibidores , Fator 2 de Crescimento de Fibroblastos/metabolismo , Glucosamina/química , Heparitina Sulfato/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Oligossacarídeos/uso terapêutico , Oligossacarídeos/toxicidade , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Transplante Heterólogo , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
The multigram-scale synthesis of a sulfation-site programmed heparin-like dodecasaccharide is described. Evaluation alongside dodecasaccharides lacking this single glucosamine O6-sulfation, or having per-O6-sulfation, shows that site-specific modification of the terminal glucosamine dramatically interconverts regulation of in vitro and in vivo biology mediated by the two important chemokines, CXCL12 (SDF1α) or CXCL8 (IL-8).
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Quimiocina CXCL12/antagonistas & inibidores , Heparitina Sulfato/química , Heparitina Sulfato/farmacologia , Interleucina-8/antagonistas & inibidores , Oligossacarídeos/química , Oligossacarídeos/farmacologia , Sequência de Carboidratos , Ensaios de Migração de Leucócitos , Células Endoteliais da Veia Umbilical Humana , Humanos , LeucócitosRESUMO
OBJECTIVE: To assess the extent and nature of psychiatric morbidity among children (aged 8 to 13 years) 15 months after a car bomb explosion in the town of Omagh, Northern Ireland. METHOD: A survey was conducted of 1945 school children attending 13 schools in the Omagh district. Questionnaires included demographic details, measures of exposure, the Horowitz Impact of Events Scale, the Birleson Self-Rating Depression Scale, and the Spence Children's Anxiety Scale. RESULTS: Children directly exposed to the bomb reported higher levels of probable PTSD (70%), and psychological distress than those not exposed. Direct exposure was more closely associated with an increase in PTSD symptoms than in general psychiatric distress. Significant predictors of increased IES scores included being male, witnessing people injured and reporting a perceived life threat but when co-morbid anxiety and depression are included as potential predictors anxiety remains the only significant predictor of PTSD scores. CONCLUSIONS: School-based studies are a potentially valuable means of screening and assessing for PTSD in children after large-scale tragedies. Assessment should consider type of exposure, perceived life threat and other co-morbid anxiety as risk factors for PTSD.
RESUMO
Heparin-like oligosaccharides mediate numerous important biological interactions, of which many are implicated in various diseases. Synthetic improvements are central to the development of such oligosaccharides as therapeutics and, in addition, there are no methods to elucidate the pharmacokinetics of structurally defined heparin-like oligosaccharides. Here we report an efficient two-cycle [4+4+4] tetrasaccharide-iteration-based approach for rapid chemical synthesis of a structurally defined heparin-related dodecasaccharide, combined with the incorporation of a latent aldehyde tag, unmasked in the final step of chemical synthesis, providing a generic end group for labelling/conjugation. We exploit this latent aldehyde tag for (3)H radiolabelling to provide the first example of this kind of agent for monitoring in vivo tissue distribution and in vivo stability of a biologically active, structurally defined heparin related dodecasaccharide. Such studies are critical for the development of related saccharide therapeutics, and the data here establish that a biologically active, synthetic, heparin-like dodecasaccharide provides good organ distribution, and serum lifetimes relevant to developing future oligosaccharide therapeutics.