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1.
Party Politics ; 30(3): 420-434, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38711799

RESUMEN

The recent increase of democratic declines around the world - "the third wave of autocratization" - has sparked a new generation of studies on the topic. Scholars tend to agree that the main threat to contemporary democracy arises from democratically elected rulers who gradually erode democratic norms. Is it possible to identify future autocratizers before they win power in elections? Linz (1978) and Levitsky and Ziblatt (2018) suggest that a lacking commitment to democratic norms reveals would-be autocratizers before they reach office. This article argues that the concept of anti-pluralism rather than populism or extreme ideology captures this. We use a new expert-coded data set on virtually all relevant political parties worldwide from 1970 to 2019 (V-Party) to create a new Anti-Pluralism Index (API) to provide the first systematic empirical test of this argument. We find substantial evidence validating that the API and Linz's litmus-test indicators signal leaders and parties that will derail democracy if and when they come into power.

2.
Proc Natl Acad Sci U S A ; 117(35): 21201-21208, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32788356

RESUMEN

We analyze the adoption of nonpharmaceutical interventions in the Organisation for Economic Co-operation and Development (OECD) countries during the early phase of the coronavirus disease 2019 (COVID-19) pandemic. Given the complexity associated with pandemic decisions, governments are faced with the dilemma of how to act quickly when their core decision-making processes are based on deliberations balancing political considerations. Our findings show that, in times of severe crisis, governments follow the lead of others and base their decisions on what other countries do. Governments in countries with a stronger democratic structure are slower to react in the face of the pandemic but are more sensitive to the influence of other countries. We provide insights for research on international policy diffusion and research on the political consequences of the COVID-19 pandemic.


Asunto(s)
Control de Enfermedades Transmisibles/métodos , Infecciones por Coronavirus/prevención & control , Gobierno , Política de Salud , Pandemias/prevención & control , Neumonía Viral/prevención & control , Betacoronavirus , COVID-19 , Infecciones por Coronavirus/epidemiología , Toma de Decisiones , Humanos , Internacionalidad , Modelos Teóricos , Neumonía Viral/epidemiología , SARS-CoV-2 , Factores de Tiempo , Incertidumbre
3.
World Dev ; 94: 321-335, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38817881

RESUMEN

The political empowerment of women is a societal process crucial to development and progress. The V-Dem women's political empowerment index (WPEI) provides information about women's civil liberties, civil society participation, and political participation globally. Spanning from 1900 to 2012, three dimensions of empowerment, and over 170 countries, it is among the most comprehensive measures of women's empowerment available. This paper presents a conceptualization of women's political empowerment and provides an overview of the construction of the index and operationalization of its three sub-dimensions: Women's civil liberties, civil society participation, and political participation. Compared to other indices measuring women's empowerment, such as the GDI, the GEM, the GII, and the CIRI data on human rights, the V-Dem index allows more precise measurement and is superior in temporal scope and coverage of countries of the Global South. The paper demonstrates the benefits of this new index and its sub-dimensions through several empirical illustrations.

4.
J Cell Mol Med ; 19(2): 371-82, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25311137

RESUMEN

The platelet-derived growth factor (PDGF) signalling pathway has been reported to play an important role in human cancers by modulating autocrine and paracrine processes such as tumour growth, metastasis and angiogenesis. Several clinical trials document the benefits of targeting this pathway; however, in cervical cancer the role of PDGF signalling in still unclear. In this study, we used siRNA against PDGF beta (PDGFBB) to investigate the cellular and molecular mechanisms of PDGFBB signalling in Ca Ski and HeLa cervical cancer cells. Our results show that PDGFBB inhibition in Ca Ski cells led to rapid alterations of the transcriptional pattern of 579 genes, genes that are known to have antagonistic roles in regulating tumour progression. Concomitantly, with the lack of significant effects on cervical cancer cells proliferation, apoptosis, migration or invasion, these findings suggests that cervical cancer cells shift between compensatory signalling pathways to maintain their behaviour. The observed autocrine effects were limited to cervical cancer cells ability to adhere to an endothelial cell (EC) monolayer. However, by inhibiting PDGFBB on cervical cells, we achieved reduced proliferation of ECs in co-culture settings and cellular aggregation in conditioned media. Because of lack of PDGF receptor expression on ECs, we believe that these effects are a result of indirect PDGFBB paracrine signalling mechanisms. Our results shed some light into the understanding of PDGFBB signalling mechanism in cervical cancer cells, which could be further exploited for the development of synergistic anti-tumour and anti-angiogenic therapeutic strategies.


Asunto(s)
Carcinogénesis/metabolismo , Proteínas Proto-Oncogénicas c-sis/metabolismo , Transducción de Señal/fisiología , Neoplasias del Cuello Uterino/metabolismo , Becaplermina , Línea Celular Tumoral , Femenino , Células HeLa , Humanos
5.
Biochim Biophys Acta ; 1828(4): 1198-204, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23261392

RESUMEN

Cell-penetrating peptides (CPPs) can internalize into cells with covalently or non-covalently bound biologically active cargo molecules, which by themselves are not able to pass the cell membrane. Direct penetration and endocytosis are two main pathways suggested for the cellular uptake of CPPs. Cargo molecules which have entered the cell via an endocytotic pathway must be released from the endosome before degradation by enzymatic processes and endosomal acidification. Endosomal entrapment seems to be a major limitation in delivery of these molecules into the cytoplasm. Bacteriorhodopsin (BR) asymmetrically introduced into large unilamellar vesicles (LUVs) was used to induce a pH gradient across the lipid bilayer. By measuring pH outside the LUVs, we observed light-induced proton pumping mediated by BR from the outside to the inside of the LUVs, creating an acidic pH inside the LUVs, similar to the late endosomes in vivo. Here we studied the background mechanism(s) of endosomal escape. 20% negatively charged LUVs were used as model endosomes with incorporated BR into the membrane and fluorescein-labeled CPPs entrapped inside the LUVs, together with a fluorescence quencher. The translocation of different CPPs in the presence of a pH gradient across the membrane was studied. The results show that the light-induced pH gradient induced by BR facilitates vesicle membrane translocation, particularly for the intermediately hydrophobic CPPs, and much less for hydrophilic CPPs. The presence of chloroquine inside the LUVs or addition of pyrenebutyrate outside the LUVs destabilizes the vesicle membrane, resulting in significant changes of the pH gradient across the membrane.


Asunto(s)
Péptidos de Penetración Celular/metabolismo , Endosomas/metabolismo , Secuencia de Aminoácidos , Cloroquina/farmacología , Concentración de Iones de Hidrógeno , Modelos Biológicos , Datos de Secuencia Molecular
6.
Antimicrob Agents Chemother ; 57(8): 3704-12, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23689723

RESUMEN

Meningococcal disease is characterized by a fast progression and a high mortality rate. Cell-penetrating peptides (CPPs), developed as vectors for cargo delivery into eukaryotic cells, share structural features with antimicrobial peptides. A screen identified two CPPs, transportan-10 (TP10) and model amphipathic peptide (MAP), with bactericidal action against Neisseria meningitidis. Both peptides were active in human whole blood at micromolar concentrations, while hemolysis remained negligible. Additionally, TP10 exhibited significant antibacterial activity in vivo. Uptake of SYTOX green into live meningococci was observed within minutes after TP10 treatment, suggesting that TP10 may act by membrane permeabilization. Apart from its bactericidal activity, TP10 suppressed inflammatory cytokine release from macrophages infected with N. meningitidis as well as from macrophages stimulated with enterobacterial and meningococcal lipopolysaccharide (LPS). Finally, incubation with TP10 reduced the binding of LPS to macrophages. This novel endotoxin-inhibiting property of TP10, together with its antimicrobial activity in vivo, indicates the possibility to design peptide-based therapies for infectious diseases.


Asunto(s)
Péptidos de Penetración Celular/aislamiento & purificación , Péptidos de Penetración Celular/farmacología , Galanina/farmacología , Inflamación/tratamiento farmacológico , Neisseria meningitidis/efectos de los fármacos , Proteínas Recombinantes de Fusión/farmacología , Venenos de Avispas/farmacología , Animales , Antibacterianos/síntesis química , Antibacterianos/farmacología , Antiinflamatorios/inmunología , Antiinflamatorios/farmacología , Péptidos Catiónicos Antimicrobianos/síntesis química , Péptidos Catiónicos Antimicrobianos/aislamiento & purificación , Péptidos Catiónicos Antimicrobianos/farmacología , Membrana Celular , Péptidos de Penetración Celular/síntesis química , Citocinas/inmunología , Evaluación Preclínica de Medicamentos , Galanina/inmunología , Humanos , Lipopolisacáridos/inmunología , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Proteína Cofactora de Membrana/genética , Proteína Cofactora de Membrana/metabolismo , Infecciones Meningocócicas/tratamiento farmacológico , Ratones , Ratones Transgénicos , Proteínas Recombinantes de Fusión/inmunología , Venenos de Avispas/inmunología
7.
Biopolymers ; 100(6): 698-704, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23893316

RESUMEN

Development of novel devices for effective nucleotide release from nanoparticles is required to improve the functionality of nonviral delivery systems, because decondensation of nucleotide/polycation complexes is considered as a key step for cytoplasmic delivery of nucleotides. Previously, PepFect6 (PF6) comprised chloroquine analog moieties and a stearylated cell-penetrating peptide to facilitate endosomal escape and cellular uptake, respectively, was developed as a device for efficient siRNA delivery. As PF6 contains bulky chloroquine analog moieties, the polyplexes are expected to be loose structure, which facilitates decondensation. In the present study, siRNA was electrostatically condensed by PF6, and the PF6/siRNA complexes were coated with lipid membranes. The surface of the nanoparticles encapsulating the PF6/siRNA core (PF6-NP) was modified with PF6 for endosomal escape (PF6/PF6-NP). The RNAi effect of PF6/PF6-NP was compared with those of stearylated cell-penetrating peptide octaarginine (R8)-modified PF6-NP, R8-modified nanoparticles encapsulating the R8/siRNA core (R8-NP) and PF6-modified R8-NP. Nanoparticles encapsulating the PF6 polyplex, especially PF/PF-NP, showed a significant knockdown effect on luciferase activity of B16-F1 cells stably expressing luciferase. siRNA was widely distributed within the cytoplasm after transfection of the nanoparticles encapsulating the PF6 polyplex, while siRNA encapsulated in the R8-presenting nanoparticles was localized within the nuclei. Thus, the siRNA distribution was dependent on the manner of peptide-modification. In conclusion, we have successfully developed PF6/PF6-NP exhibiting a potent RNAi effect resulting from high cellular uptake, efficient endosomal escape and decondensation of the polyplexes based on the multifunctional cell penetrating peptide PF6. PF6 is therefore a useful pluripotential device for siRNA delivery.


Asunto(s)
Péptidos de Penetración Celular , ARN Interferente Pequeño , Péptidos de Penetración Celular/química , Endosomas , Humanos , Nanopartículas/química , Transfección
8.
FASEB J ; 26(3): 1172-80, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22138034

RESUMEN

Cell-penetrating peptides (CPPs) are short cationic peptides that penetrate cells by interacting with the negatively charged plasma membrane; however, the detailed uptake mechanism is not clear. In contrary to the conventional mode of action of CPPs, we show here that a CPP, PepFect14 (PF14), forms negatively charged nanocomplexes with oligonucleotides and their uptake is mediated by class-A scavenger receptors (SCARAs). Specific inhibitory ligands of SCARAs, such as fucoidin, polyinosinic acid, and dextran sulfate, totally inhibit the activity of PF14-oligonucleotide nanocomplexes in the HeLa pLuc705 splice-correction cell model, while nonspecific, chemically related molecules do not. Furthermore, RNA interference (RNAi) knockdown of SCARA subtypes (SCARA3 and SCARA5) that are expressed in this cell line led to a significant reduction of the activity to <50%. In line with this, immunostaining shows prevalent colocalization of the nanocomplexes with the receptors, and electron microscopy images show no binding or internalization of the nanocomplexes in the presence of the inhibitory ligands. Interestingly, naked oligonucleotides also colocalize with SCARAs when used at high concentrations. These results demonstrate the involvement of SCARA3 and SCARA5 in the uptake of PF14-oligonucleotide nanocomplexes and suggest for the first time that some CPP-based systems function through scavenger receptors, which could yield novel possibilities to understand and improve the transfection by CPPs.


Asunto(s)
Péptidos de Penetración Celular/metabolismo , Proteínas de Choque Térmico/metabolismo , Lipopéptidos/metabolismo , Oligonucleótidos/metabolismo , Receptores Depuradores de Clase A/metabolismo , Transporte Biológico/efectos de los fármacos , Membrana Celular/metabolismo , Péptidos de Penetración Celular/farmacocinética , Sulfato de Dextran/farmacología , Fetuínas/farmacología , Expresión Génica , Células HeLa , Proteínas de Choque Térmico/antagonistas & inhibidores , Proteínas de Choque Térmico/genética , Humanos , Inmunohistoquímica , Lipopéptidos/farmacocinética , Microscopía Electrónica de Transmisión , Nanoestructuras/ultraestructura , Unión Proteica/efectos de los fármacos , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Receptores Depuradores de Clase A/antagonistas & inhibidores , Receptores Depuradores de Clase A/genética
9.
Nucleic Acids Res ; 39(12): 5284-98, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21345932

RESUMEN

Numerous human genetic diseases are caused by mutations that give rise to aberrant alternative splicing. Recently, several of these debilitating disorders have been shown to be amenable for splice-correcting oligonucleotides (SCOs) that modify splicing patterns and restore the phenotype in experimental models. However, translational approaches are required to transform SCOs into usable drug products. In this study, we present a new cell-penetrating peptide, PepFect14 (PF14), which efficiently delivers SCOs to different cell models including HeLa pLuc705 and mdx mouse myotubes; a cell culture model of Duchenne's muscular dystrophy (DMD). Non-covalent PF14-SCO nanocomplexes induce splice-correction at rates higher than the commercially available lipid-based vector Lipofectamine 2000 (LF2000) and remain active in the presence of serum. Furthermore, we demonstrate the feasibility of incorporating this delivery system into solid formulations that could be suitable for several therapeutic applications. Solid dispersion technique is utilized and the formed solid formulations are as active as the freshly prepared nanocomplexes in solution even when stored at an elevated temperatures for several weeks. In contrast, LF2000 drastically loses activity after being subjected to same procedure. This shows that using PF14 is a very promising translational approach for the delivery of SCOs in different pharmaceutical forms.


Asunto(s)
Péptidos de Penetración Celular/química , Lipopéptidos/química , Oligonucleótidos Antisentido/administración & dosificación , Empalme Alternativo , Animales , Péptidos de Penetración Celular/metabolismo , Péptidos de Penetración Celular/toxicidad , Células Cultivadas , Medios de Cultivo , Medio de Cultivo Libre de Suero , Endocitosis , Células HeLa , Humanos , Cinética , Luz , Lipopéptidos/metabolismo , Lipopéptidos/toxicidad , Ratones , Fibras Musculares Esqueléticas/metabolismo , Nanoestructuras/química , Oligonucleótidos Antisentido/química , Oligonucleótidos Antisentido/metabolismo , Dispersión de Radiación , Soluciones , Temperatura
10.
BMC Neurosci ; 13: 86, 2012 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-22827889

RESUMEN

BACKGROUND: Spinocerebellar ataxia type 7 (SCA7) is one of nine inherited neurodegenerative disorders caused by polyglutamine (polyQ) expansions. Common mechanisms of disease pathogenesis suggested for polyQ disorders include aggregation of the polyQ protein and induction of oxidative stress. However, the exact mechanism(s) of toxicity is still unclear. RESULTS: In this study we show that expression of polyQ expanded ATXN7 in a novel stable inducible cell model first results in a concomitant increase in ROS levels and aggregation of the disease protein and later cellular toxicity. The increase in ROS could be completely prevented by inhibition of NADPH oxidase (NOX) complexes suggesting that ATXN7 directly or indirectly causes oxidative stress by increasing superoxide anion production from these complexes. Moreover, we could observe that induction of mutant ATXN7 leads to a decrease in the levels of catalase, a key enzyme in detoxifying hydrogen peroxide produced from dismutation of superoxide anions. This could also contribute to the generation of oxidative stress. Most importantly, we found that treatment with a general anti-oxidant or inhibitors of NOX complexes reduced both the aggregation and toxicity of mutant ATXN7. In contrast, ATXN7 aggregation was aggravated by treatments promoting oxidative stress. CONCLUSION: Our results demonstrates that oxidative stress contributes to ATXN7 aggregation as well as toxicity and show that anti-oxidants or NOX inhibition can ameliorate mutant ATXN7 toxicity.


Asunto(s)
Proteínas del Tejido Nervioso/metabolismo , Proteínas del Tejido Nervioso/farmacología , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Animales , Ataxina-7 , Línea Celular Transformada , Inhibidores Enzimáticos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/genética , Glutatión Transferasa/metabolismo , Proteínas Fluorescentes Verdes/genética , Humanos , Peróxido de Hidrógeno/farmacología , Mutación/genética , NADPH Oxidasas/genética , NADPH Oxidasas/metabolismo , Proteínas del Tejido Nervioso/genética , Miembro 1 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Oxidantes/farmacología , Estrés Oxidativo/genética , Péptidos/genética , Ratas , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa-1 , Transfección/métodos
11.
Alcohol Alcohol ; 46(2): 170-6, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21273301

RESUMEN

AIMS: To compare the mortality of female alcoholics randomly assigned to the woman-only programme 'Early treatment for Women with Alcohol Addiction' (EWA) versus those who received mixed gender 'Treatment As Usual' (TAU). METHODS: Randomized controlled trial involving 2-year follow-up by personal interview and mortality register data through 27 years of 200 women first time treated for alcohol use disorder (AUD; EWA, n = 100 and TAU, n = 100), who were consecutively recruited during 1983-1984. Data from the Causes of Death Register were used to test for mortality differences related to group interaction predictors such as age, inpatient versus outpatient status at intake and 2-year drinking outcome. RESULTS: Significantly lower mortality was found among younger women who participated in EWA compared with those who received TAU. This difference lasted nearly 20 years after intake to treatment. For women who only needed outpatient treatment, reduced mortality was found in the EWA group, even for older women. Increased mortality was found for TAU women who did not attend the 2-year follow-up compared with those who attended; no such difference was found for EWA women. This indicates different attrition mechanisms in the two groups. Thus, previously reported treatment effects may have been underestimated. EWA was a more comprehensive programme than TAU while also being single gender. CONCLUSIONS: EWA, specifically developed to meet a broad spectrum of problems among women with AUDs, was more effective than TAU, a mixed gender programme. It was not possible to separate whether this was in part because it was a more comprehensive programme, as well as being single gender.


Asunto(s)
Alcoholismo/mortalidad , Alcoholismo/terapia , Factores de Edad , Alcoholismo/prevención & control , Femenino , Humanos , Masculino , Prevención Secundaria , Factores Sexuales , Nivel de Atención , Templanza , Factores de Tiempo
12.
Democratization ; 28(5): 885-907, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34393609

RESUMEN

This article introduces a novel conceptualization of democratic resilience - a two-stage process where democracies avoid democratic declines altogether or avert democratic breakdown given that such autocratization is ongoing. Drawing on the Episodes of Regime Transformation (ERT) dataset, we find that democracies have had a high level of resilience to onset of autocratization since 1900. Nevertheless, democratic resilience has become substantially weaker since the end of the Cold War. Fifty-nine episodes of sustained and substantial declines in democratic practices have occurred since 1993, leading to the unprecedented breakdown of 36 democratic regimes. Ominously, we find that once autocratization begins, only one in five democracies manage to avert breakdown. We also analyse which factors are associated with each stage of democratic resilience. The results suggest that democracies are more resilient when strong judicial constraints on the executive are present and democratic institutions were strong in the past. Conversely and adding nuance to the literature, economic development is only associated with resilience to onset of autocratization, not to resilience against breakdown once autocratization has begun.

13.
Patterns (N Y) ; 1(4): 100056, 2020 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-33205115

RESUMEN

Questions such as how democratic a country is, how free are its media, or how independent is its judiciary are highly important to researchers and decision makers. We describe a research infrastructure that produces the world's largest dataset on democracy, governance, human rights, and related topics. The dataset is far more resolved and accurate than previous efforts, currently covers 202 political units from 1789 until the present, and is regularly updated each spring. The infrastructure involves an online survey of over 3,000 experts from 180 countries. Survey design and advanced statistical techniques are crucial for assuring data validity. The infrastructure also provides reports and analyses based on the data and easy-to-use tools for exploring and graphing the data.

14.
Eur J Polit Res ; 59(2): 465-487, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32421052

RESUMEN

Authoritarian incumbents routinely use democratic emulation as a strategy to extend their tenure in power. Yet, there is also evidence that multiparty competition makes electoral authoritarianism more vulnerable to failure. Proceeding from the assumption that the outcomes of authoritarian electoral openings are inherently uncertain, it is argued in this article that the institutionalisation of elections determines whether electoral authoritarianism promotes stability or vulnerability. By 'institutionalisation', it is meant the ability of authoritarian regimes to reduce uncertainty over outcomes as they regularly hold multiparty elections. Using discrete-time event-history models for competing risks, the effects of sequences of multiparty elections on patterns of regime survival and failure in 262 authoritarian regimes from 1946 to 2010 are assessed, conditioned on their degree of competitiveness. The findings suggest that the institutionalisation of electoral uncertainty enhances authoritarian regime survival. However, for competitive electoral authoritarian regimes this entails substantial risk. The first three elections substantially increase the probability of democratisation, with the danger subsequently diminishing. This suggests that convoking multiparty competition is a risky game with potentially high rewards for autocrats who manage to institutionalise elections. Yet, only a small number of authoritarian regimes survive as competitive beyond the first few elections, suggesting that truly competitive authoritarianism is hard to institutionalise. The study thus finds that the question of whether elections are dangerous or stabilising for authoritarianism is dependent on differences between the ability of competitive and hegemonic forms of electoral authoritarianism to reduce electoral uncertainty.

15.
Ambio ; 49(2): 419-433, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31236785

RESUMEN

Increasing human pressure threatens plant and animal species with extinction worldwide. National political institutions constitute an important arena for biodiversity conservation. Yet, the relationship between how democratic these national institutions are and a country's efforts towards and track-record for biodiversity conservation remains poorly understood. In this review, we outline the theoretical links between democracy and biodiversity conservation and review the empirical literature testing them. While more studies reported a positive than a negative relation between democracy and biodiversity conservation (15 vs. 11), the most common result was a mixed relationship (28), often conditioned on economic factors. The use of different proxies to measure biodiversity, including deforestation, protected areas, threatened species, and fishery statistics emerged as a primary obstacle for synthesis. We suggest overcoming this caveat together with a consistent definition of democratic institutions and a standardized statistical framework as research priorities to improve policies against the global biodiversity loss.


Asunto(s)
Biodiversidad , Democracia , Animales , Conservación de los Recursos Naturales , Especies en Peligro de Extinción , Humanos
16.
Soc Sci Q ; 100(3): 838-856, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31068735

RESUMEN

OBJECTIVES: This article presents a new method inspired by evolutionary biology for analyzing longer sequences of requisites for the emergence of particular outcome variables across numerous combinations of ordinal variables in social science analysis. METHODS: The approach is a sorting algorithm through repeated pairwise investigations of states in a set of variables and identifying what states in the variables occur before states in all other variables. We illustrate the proposed method by analyzing a set of variables from version 7.1 of the V-Dem data set (Coppedge et al. 2017. Varieties of Democracy (V-Dem) Project; Pemstein et al. 2017. University of Gothenburg, Varieties of Democracy Institute: Working Paper No. 21). With a large set of indicators measured over many years, the method makes it possible to identify and compare long, complex sequences across many variables. RESULTS: This affords an opportunity, for example, to disentangle the sequential requisites of failing and successful sequences in democratization, or if requisites are different during different time periods. CONCLUSIONS: For policy purposes, this is instrumental: Which components of democracy occur earlier and which later? Which components of democracy are therefore the ideal targets for democracy promotion at different stages?

17.
Eur J Polit Res ; 56(4): 735-756, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38463414

RESUMEN

What determines countries' successful transition to democracy? This article explores the impact of granting civil rights in authoritarian regimes and especially the gendered aspect of this process. It argues that both men's and women's liberal rights are essential conditions for democratisation to take place: providing both women and men rights reduces an inequality that affects half of the population, thus increasing the costs of repression and enabling the formation of women's organising - historically important to spark protests in initial phases of democratisation. This argument is tested empirically using data that cover 173 countries over the years 1900-2012 and contain more nuanced measures than commonly used. Through novel sequence analysis methods, the results suggest that in order to gain electoral democracy a country first needs to furnish civil liberties to both women and men.

18.
Methods Mol Biol ; 1324: 163-74, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26202269

RESUMEN

The investigation of uptake mechanisms for cell-penetrating peptides (CPPs) is and has been an ongoing project for as long as the peptides have been known, a time period that now spans over two decades. The ultimate answer is yet to be revealed and the current understanding is that no "one" mechanism will ever be found. The reason for this is that the uptake mechanism seems to be dependent on a multitude of factors that include which CPP, what cells are used, whether or not there is cargo and what the cargo is. CPPs are capable of delivering a variety of bio-macromolecules that are by themselves unable to enter into cells. Our group has reported on many different peptides in recent years, many aimed at delivering various oligonucleotide-based cargoes. These peptides have utilized the inherent positive charge of the peptides and some rationally designed modifications to non-covalently complex oligonucleotides and bring them into cells. In this chapter, we present a brief overview of the current proposals for the uptake mechanisms of CPPs and describe methods for detecting and evaluating the role of scavenger receptor class A receptors in the uptake of non-covalent cell-penetrating peptide:oligonucleotide complexes.


Asunto(s)
Péptidos de Penetración Celular/metabolismo , Nanopartículas/metabolismo , Receptores Depuradores de Clase A/metabolismo , Animales , Transporte Biológico , Técnicas de Cultivo de Célula/métodos , Péptidos de Penetración Celular/química , Endocitosis , Técnicas de Silenciamiento del Gen/métodos , Silenciador del Gen , Humanos , Nanopartículas/química , Receptores Depuradores de Clase A/genética , Regulación hacia Arriba
19.
J Control Release ; 206: 58-66, 2015 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-25769688

RESUMEN

Cell-penetrating peptides (CPPs) have been used as vehicles to deliver various cargos into cells and are promising as tools to deliver therapeutic biomolecules such as oligonucleotides both in vitro and in vivo. CPPs are positively charged and it is believed that CPPs deliver their cargo in a receptor-independent manner by interacting with the negatively charged plasma membrane and thereby inducing endocytosis. In this study we examine the mechanism of uptake of several different, well known, CPPs that form complexes with oligonucleotides. We show that these CPP:oligonucleotide complexes are negatively charged in transfection-media and their uptake is mediated by class A scavenger receptors (SCARA). These receptors are known to promiscuously bind to, and mediate uptake of poly-anionic macromolecules. Uptake of CPP:oligonucleotide complexes was abolished using pharmacological SCARA inhibitors as well as siRNA-mediated knockdown of SCARA. Additionally, uptake of CPP:oligonucleotide was significantly increased by transiently overexpressing SCARA. Furthermore, SCARA inhibitors also blocked internalization of cationic polymer:oligonucleotide complexes. Our results demonstrate that the previous held belief that CPPs act receptor independently does not hold true for CPP:oligonucleotide complexes, as scavenger receptor class A (SCARA) mediates the uptake of all the examined CPP:oligonucleotide complexes in this study.


Asunto(s)
Péptidos de Penetración Celular/metabolismo , Oligonucleótidos/administración & dosificación , Plásmidos/administración & dosificación , Polímeros/metabolismo , Receptores Depuradores de Clase A/metabolismo , Línea Celular , Endocitosis , Células HeLa , Humanos , ARN Interferente Pequeño/genética , Receptores Depuradores de Clase A/antagonistas & inhibidores , Receptores Depuradores de Clase A/genética , Transfección
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