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1.
Psychother Res ; : 1-16, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37848189

RESUMO

Objective This study investigated the reasons why pedohebephilic clients disclose their sexual attraction to children in therapy and the experiences associated with this decision among English-speaking samples. Method: The pre-registered online survey combined (1) quantitative correlational data of self-reported improvement, alliance, therapist reaction to disclosure, and the belief that mandatory reporting laws were in place, and (2) qualitative data about reasons for disclosure or no disclosure as well as perceived consequences. The sample consisted of pedohebephilic people who have been clients in therapy and have disclosed (n = 96) or not disclosed (n = 40). Results: While the disclosure and no disclosure groups did not differ in improvement or beliefs about mandatory reporting, those who had disclosed reported a stronger alliance. Clients who did not perceive the therapist's reaction as supportive reported less improvement than the no disclosure group. Thematic analysis of qualitative data identified three themes concerning motives for disclosing or not disclosing and a fourth regarding differential impacts of disclosure. Discussion: This study indicates that disclosing pedohebephilia does not in and of itself lead to improvement but is contingent on a therapist's reaction.

2.
Arch Sex Behav ; 51(8): 4125-4139, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36175817

RESUMO

The primary label for people who are sexually attracted to children ("pedophile") is conflated with sexual offending behavior and tainted with stigma. In the present pre-registered mixed-method study, we therefore investigated attitudes and preferences regarding "pedophile/hebephile" and other labels among 286 people who report a stronger or equally strong sexual attraction to prepubescent and pubescent children than to adults. Overall, quantitative data showed acceptance of "pedophile/hebephile" as well as a range of alternative labels in a personal (Labeling Oneself) and a professional context (Being Labeled by Others). "Minor-attracted person" and "pedophile/hebephile" received generally higher support than other terms and appeared to be least divisive across three major online fora. Qualitative data revealed four themes: "Contested self-labels," "Person-first language and pathologizing sexuality/identity," "Stigma and shame," and "Reclaiming the pedophile label." Our results allow deeper insight into reasons for adopting certain labels over others, as well as difficulties of finding a non-stigmatizing label. We discuss limitations of the study and practical implications for clinical and research contexts.


Assuntos
Pedofilia , Delitos Sexuais , Adulto , Criança , Humanos , Comportamento Sexual , Atitude , Identidade de Gênero
3.
Pharmaceutics ; 14(2)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35214034

RESUMO

Formulating pharmaceutical cocrystals as inhalable dosage forms represents a unique niche in effective management of respiratory infections. Favipiravir, a broad-spectrum antiviral drug with potential pharmacological activity against SARS-CoV-2, exhibits a low aqueous solubility. An ultra-high oral dose is essential, causing low patient compliance. This study reports a Quality-by-Design (QbD)-guided development of a carrier-free inhalable dry powder formulation containing a 1:1 favipiravir-theophylline (FAV-THP) cocrystal via spray drying, which may provide an alternative treatment strategy for individuals with concomitant influenza infections and chronic obstructive pulmonary disease/asthma. The cocrystal formation was confirmed by single crystal X-ray diffraction, powder X-ray diffraction, and the construction of a temperature-composition phase diagram. A three-factor, two-level, full factorial design was employed to produce the optimized formulation and study the impact of critical processing parameters on the resulting median mass aerodynamic diameter (MMAD), fine particle fraction (FPF), and crystallinity of the spray-dried FAV-THP cocrystal. In general, a lower solute concentration and feed pump rate resulted in a smaller MMAD with a higher FPF. The optimized formulation (F1) demonstrated an MMAD of 2.93 µm and an FPF of 79.3%, suitable for deep lung delivery with no in vitro cytotoxicity observed in A549 cells.

4.
Int J Offender Ther Comp Criminol ; 66(12): 1213-1236, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-32917108

RESUMO

Prison-based democratic therapeutic communities (TCs) provide an alternative to mainstream prison, where prisoners can work on psychological difficulties and address offending behavior. Research demonstrates TCs are effective at reducing reoffending rates for residents who stay in therapy 18+ months, and those who drop out of TCs offend at a significantly higher rate than those who complete therapy. Thus, it is important to reduce attrition in TCs. No research has yet explored the explanations for TC drop out offered by those with sexual convictions. The present study uses Interpretive Phenomenological Analysis to qualitatively explore the accounts of men with sexual convictions (n = 7) who dropped out of a TC in a UK prison. Results highlight that issues surrounding external responsivity, therapeutic relationships, and treatment readiness were salient in the participants' accounts of drop out. This research has implications for TCs seeking to better understand and address attrition of people with sexual convictions.


Assuntos
Prisioneiros , Comunidade Terapêutica , Humanos , Masculino , Motivação , Prisioneiros/psicologia , Prisões , Comportamento Sexual
5.
Arch Sex Behav ; 51(2): 945-960, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34716500

RESUMO

The stigmatization of people with pedophilic sexual interests is a topic of growing academic and professional consideration, owing to its potential role in moderating pedophiles' emotional well-being, and motivation and engagement in child abuse prevention schemes. Thus, improving attitudes and reducing stigmatization toward this group is of paramount importance. Prior research has suggested that narrative humanization-presenting personal stories of self-identified non-offending pedophiles-could be one route to doing this. However, this work has only been conducted with students or trainee psychotherapists, meaning the public generalizability of this method is still unknown. In this study, we compared two stigma interventions to test whether narratives reduce stigma toward people with pedophilic interests more effectively than an informative alternative (scientific information about pedophilia). Using a longitudinal experimental design with a lack of non-intervention control (initial N = 950; final N = 539), we found that narratives had consistently positive effects on all measured aspects of stigmatization (dangerousness, intentionality), whereas an informative alternative had mixed results, and actually increased perceptions of pedophiles' levels of deviance. These effects were still present four months after the initial presentation. We discuss these data in relation to ongoing debates about treating pedophilia as a public health issue requiring a broad societal approach to well-being and child abuse prevention.


Assuntos
Abuso Sexual na Infância , Pedofilia , Delitos Sexuais , Atitude , Criança , Humanos , Pedofilia/prevenção & controle , Pedofilia/psicologia , Estigma Social , Estereotipagem
6.
Artigo em Inglês | MEDLINE | ID: mdl-34208321

RESUMO

United Kingdom Police custody is one of the most challenging of work environments, liable to excessive demands and reduced well-being. Being difficult to access, it is also a much-neglected area of research that has focused on one or two roles, rather than the full range available, and on individual-level research, rather than a more comprehensive multilevel understanding of how organizational culture and climate can simultaneously influence a range of well-being outcomes. The present longitudinal study explored all types of roles, in both the public and private sectors, across seven English police forces and 26 custody sites (N = 333, response rate 46.57%, with repeated returns = 370). The Integrated Multilevel Model of Organizational Culture and Climate (IMMOCC) was applied to examine the organizational-level influences on individual well-being. Results indicated that (1) custody sergeants were most vulnerable to low well-being, followed by publicly contracted detention officers; (2) shared leadership (a source of team cohesion) was linked to four of six well-being outcomes; (3) two sub-components of culture reflected tensions never acknowledged before, especially in respect of role; and (4) reverse relationships existed between well-being outcomes and the dimensions of culture and climate. The findings inform practical recommendations, including resilience training and the need to raise the status of police custody, while also highlighting concerns about private sector scrutiny that may be relevant to other professions.


Assuntos
Polícia , Prisioneiros , Humanos , Estudos Longitudinais , Cultura Organizacional , Reino Unido
7.
Curr Psychiatry Rep ; 22(9): 51, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32700036

RESUMO

PURPOSE OF REVIEW: We review the evidence base for men who categorically deny responsibility for their sexual crimes. Specifically, we consider the characteristics of these individuals and the purpose or function of the denial, whether denial leads to an increased risk of reoffending and the evidence for different treatment options available for deniers. RECENT FINDINGS: Whilst there is some evidence that deniers differ from admitters, it appears that categorical denial is a strategy used to reduce negative consequences such as a sense of shame or the fear of losing family support. The common assumption that deniers are more likely to commit further sexual crimes is not supported by the evidence to date. There remains a lack of evidence as to the best treatment approach to use. We conclude that more research is necessary. We suggest that a lack of consideration of the function of denial or the adaptive benefits of denial could explain inconsistent findings in relation to the characteristics of deniers and why denial does not appear related to recidivism. Whilst the available evidence does not support most approaches aimed at overcoming denial, we suggest that some of the most promising approaches seem to be non-disclosure-based focusing on reducing stigma; however, it is conceded that the evidence for such approaches is still emerging.


Assuntos
Negação em Psicologia , Delitos Sexuais , Humanos , Masculino , Comportamento Sexual , Estigma Social
8.
Sex Abuse ; 32(6): 727-750, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31023187

RESUMO

Understanding how individuals with sexual convictions experience prison and its environment is important because such experiences can affect rehabilitation outcomes. This is the first qualitative longitudinal investigation that explores the experiences of prisoners in a prison exclusively for individuals with sexual convictions over time. The purpose of this research was to explore the rehabilitative and therapeutic climate of a recently re-rolled prison (a general prison turned into a prison only for individuals who have sexually offended) at two time points (T1 at re-roll and T2 a year later). The study focuses on prisoners' perspectives of the purpose of the prison, experience of prison life, relationships in the prison, and the prison regime over time. Twenty interviews were conducted across the time points and revealed two main superordinate themes: "'Being' in a prison for individuals with sexual convictions" and "obstructions to change." This research adds to the emerging body of knowledge surrounding the importance of the wider prison environment on the rehabilitation of individuals with sexual convictions and on the benefits and risks of co-locating men who have committed sexual offenses in the same prison site. It also has implications wider than rehabilitation of those convicted of sexual offenses and has insights for the types of environment and prisoner-staff relationships that are conducive to rehabilitation.


Assuntos
Prisioneiros/psicologia , Prisões/organização & administração , Delitos Sexuais/psicologia , Adulto , Idoso , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa
9.
Sex Abuse ; 31(8): 886-907, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29790431

RESUMO

Circles of support and accountability (CoSA) in the prison-model begin prior to the core members' release from prison and continue with them on release in to the community. The purpose of this study was to explore the expectations of release of those convicted of a sexual offense and how this develops during their participation in the prison sessions of CoSA. The research question was to consider how the prison-model of CoSA relates to the desistance of crime, in particular the phases of desistance developed by Gobbels, Ward, and Willis. Data were collected using both phenomenological interviews and repertory grids at two different time points; prior to starting the circle in prison (n = 9) and just before release (n = 5). The findings suggest the prison sessions provide a sense of support and "no longer being alone" often absent in those who sexually offend. The additional prison sessions enabled the participants to experience this during their approaching release date; a stressful period that was characterized by anxiety. Further research is now required to explore whether circles in the prison-model are able to encourage and reinforce the cognitive change required for desistance, enabling the core members to successfully manage their underlying anxieties surrounding societal stigmatization.


Assuntos
Criminosos/psicologia , Reincidência/prevenção & controle , Delitos Sexuais/psicologia , Responsabilidade Social , Apoio Social , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Prisioneiros/psicologia , Prisões , Reincidência/psicologia
10.
Sex Abuse ; 30(6): 728-754, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28366051

RESUMO

Sexual interest in children is one of the most strongly predictive of the known risk factors for sexual reconviction. It is an important aspect of risk assessment to identify the presence of such interest, and an important task for treatment providers to address such a sexual interest where it is present. It has been argued that understanding pedophiles' deviant sexual interest in children can enhance risk assessment, management, and treatment planning. This research study aims to explore the phenomenology of deviant sexual interest in children, the impact it has on pedophilic offenders' identities, and their views on the treatability of that interest. The study used semistructured interviews and repertory grids to make sense of participants' experiences. The results revealed three superordinate themes: "'living' with a deviant sexual interest," "relational sexual self," and "possible and feared sexual self." The analysis unpacks these themes and repertory grid analysis is used to explore a subset of participants' identities in more detail. The results reveal that there needs to be an acceptance from both client and therapist that their sexual interest in children may never go away. Through this acceptance, clients could work on enhancing sexual self-regulation, recognizing their triggers, and so managing their sexual thoughts, feelings, and behavior. Implications for treatment are also discussed.


Assuntos
Criminosos/psicologia , Pedofilia/psicologia , Autoimagem , Adolescente , Adulto , Humanos , Masculino , Fatores de Risco , Adulto Jovem
11.
Sex Abuse ; 30(7): 759-780, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29188754

RESUMO

Individuals incarcerated in prisons across the United Kingdom and abroad are able to volunteer for a variety of peer-support roles, which are characterized by prisoner-to-prisoner helping. Some research has found that such roles can represent turning points in the lives of those who have offended and encourage movements toward desistance. This proposed redemptive influence is argued to result from the prosocial behaviors that such roles appear to elicit in their holders. The present study aims to explore the mechanics of this claimed influence. While a limited amount of research has attempted this on a general offending population, no research has done so with a sample of sexual offenders. Given the intensive treatment programs involved in such contexts, and the requirements for sexual offenders to demonstrate reduced risk, the authors believe those serving time for sexual offenses represent an important sample on which to explore the potentially redemptive properties of peer-support roles. To this end, 13 peer supporters participated in semistructured interviews. Transcripts were analyzed using a phenomenologically oriented thematic analysis. Results suggest that sexual offenders who adopt peer-support roles are able to live up to desired selves by "doing good" in prison, "giving back," and consequently resisting negative labels. These benefits have been theoretically linked with better reintegration outcomes for sexual offenders, who are publicly denigrated in the extreme and find it especially difficult to (re)integrate. Suggestions regarding the future utility of such schemes are offered.


Assuntos
Criminosos/psicologia , Grupo Associado , Prisioneiros/psicologia , Autoimagem , Delitos Sexuais , Apoio Social , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prisões
12.
Int J Offender Ther Comp Criminol ; 60(4): 371-96, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25305193

RESUMO

Research evidence demonstrates that sex offender treatment programmes (SOTPs) can reduce the number of sex offenders who are reconvicted. However, there has been much less empirical research exploring the experiences and perspectives of the prison environment within which treatment takes place. This is important, particularly for sexual offenders, as they often face multiple stigmas in prison. This study used a mixed-methods approach to explore the experiences of prisoners and staff at a therapeutically orientated sexual offenders' prison to understand whether the prison environment was conducive to rehabilitation. The quantitative strand of the research sampled prisoners (n = 112) and staff (n = 48) from a therapeutically orientated sex offenders prison. This strand highlighted that both prisoners and staff had positive attitudes toward offenders and high beliefs that offenders could change. Importantly, the climate was rated positively and, in particular, participants had very high ratings of "experienced safety." The qualitative strand of the research consisted of semistructured interviews with prisoners (n = 15) and a range of prison staff (n = 16). The qualitative analysis revealed positive prisoner views toward staff relationships, with most participants articulating that the prison and its staff had contributed to positive change in prisoners. Crucially, the environment was perceived as safe and allowed prisoners "headspace" to work through problems and contemplate change. This research offers some support to the notion that context is important for sex offender rehabilitation.


Assuntos
Atitude do Pessoal de Saúde , Humanismo , Prisioneiros/psicologia , Prisões/legislação & jurisprudência , Delitos Sexuais/legislação & jurisprudência , Delitos Sexuais/psicologia , Comunidade Terapêutica , Adaptação Psicológica , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Entrevista Psicológica , Masculino , Pessoa de Meia-Idade , Prisões/organização & administração , Resolução de Problemas , Avaliação de Programas e Projetos de Saúde , Meio Social , Inquéritos e Questionários
13.
Iran J Pharm Res ; 13(3): 785-95, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25276179

RESUMO

This study aimed to determine the aerosolization behavior of a nanodispersion of budesonide, prepared using microfluidic reactors. The size and morphology of budesonide nanoparticles were characterized by photon correlation spectroscopy (PCS) and transmission electron microscopy (TEM). Processing/formulation parameters for formation of the nanoparticles were studied to determine their effects on the particle size. Results showed a narrow distribution for budesonide nanodispersion with spherical and smooth surfaced particles. To investigate the in-vitro aerosolization performance of the nanodispersion, the preparation was compared with a commercially available budesonide microsuspension using the Comité Européen Normalization (CEN) methodology. Aerosolization results showed that the fine particle fraction (FPF) generated from the budesonide nanodispersion was significantly higher than that of the marketed budesonide (ie. mean (SD) 56.88 (3.37)% vs. 38.04 (7.82)%, respectively). Additionally, mass median aerodynamic diameter (MMAD) of nano-budesonide dispersion was significantly smaller than the microsuspension (ie. mean (SD) 3.91 (0.49) vs. 6.22 (1.09) µm, respectively), with nebulization time of nano-budesonide dispersion significantly shorter than the marketed budesonide microsuspension (ie. 12.3 (0.37) vs. 14.85 (0.36) min, respectively). The produced nanodispersion was found to be stable over a period of 10 days if stored at 4 °C.

14.
J Interpers Violence ; 29(9): 1698-731, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24442912

RESUMO

Denial in sexual offenders represents the first barrier to successful treatment a clinician is likely to face. Most sex offender treatment programs devote significant time to overcoming denial, with most programs having a focus on disclosure and "accepting responsibility." This is the first study that has aimed to make sense of sexual offenders' denial through a rigorous qualitative analysis. The main objective was to explore the experiences and lived worlds of sexual offenders in denial. A qualitative phenomenological methodology combining interpretative phenomenological analysis and repertory grids was implemented. Ten incarcerated sexual offenders in categorical denial participated in the research. The analysis revealed the narrative, relational, and self-reconstructive properties of denial and discusses the role and function denial may be playing for sexual offenders. The results highlight that denial can be viewed as a form of "sense making" and that clinically relevant treatment targets can be elicited without disclosure. It is concluded that viewing denial as a barrier to treatment impedes constructive work with offenders, and implications for treatment are discussed.


Assuntos
Negação em Psicologia , Delitos Sexuais/psicologia , Adulto , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Autoimagem , Estigma Social , Adulto Jovem
15.
Chemistry ; 19(32): 10663-71, 2013 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-23794534

RESUMO

Four new ternary crystalline molecular complexes have been synthesised from a common 3,5-dinitrobenzoic acid (3,5-dnda) and 4,4'-bipyridine (bipy) pairing with a series of amino-substituted aromatic compounds (4-aminobenzoic acid (4-aba), 4-(N,N-dimethylamino)benzoic acid (4-dmaba), 4-aminosalicylic acid (4-asa) and sulfanilamide (saa)). The ternary crystals were created through the application of complementary charge transfer and hydrogen-bonding interactions. For these systems a dimer was created through a charge-transfer interaction between two of the components, while hydrogen bonding between the third molecule and this dimer completed the construction of the ternary co-crystal. All resulting structures display the same acid⋅⋅⋅pyridine interaction between 3,5-dnba and bipy. However, changing the third component causes the proton of this bond to shift from neutral OH⋅⋅⋅N to a salt form, O(-) ⋅⋅⋅HN(+) , as the nature of the group hydrogen bonding to the carboxylic acid was changed. This highlights the role of the crystal environment on the level of proton transfer and the utility of ternary systems for the study of this process.


Assuntos
Nitrobenzoatos/química , Piridinas/química , Cristalografia por Raios X , Dimerização , Ligação de Hidrogênio , Conformação Molecular , Teoria Quântica , Termodinâmica
16.
Int J Offender Ther Comp Criminol ; 57(3): 332-56, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22186882

RESUMO

Denial in sexual offenders represents the first barrier to successful treatment a clinician is likely to face. However, there is currently no research focusing on the experiences of treatment professionals who treat and manage deniers. This study aimed to bridge this research gap and to gain an insight into the perspectives and experiences of professionals who treat and manage sex offenders in denial. The purpose was to ascertain their views on whether deniers are amenable to treatment, whether they should be offered treatment (as presently they are excluded from sex offender programmes), and what they believe may work with this population. A qualitative methodology was used, and treatment professionals were interviewed using semistructured interviews at a HM Prison in England. The main findings indicated that participants viewed denial as a barrier to treatment and that categorical deniers should be excluded from treatment. Implications for treatment are discussed, and it is concluded that viewing denial as a barrier to treatment impedes constructive work with offenders. It is argued that denial as an organising principle for treatment needs rethinking and that admittance may not be required for personal reform.


Assuntos
Atitude do Pessoal de Saúde , Terapia Comportamental , Prisioneiros/legislação & jurisprudência , Prisioneiros/psicologia , Delitos Sexuais/legislação & jurisprudência , Delitos Sexuais/psicologia , Socialização , Adulto , Inglaterra , Culpa , Humanos , Masculino , Pessoa de Meia-Idade , Motivação , Prognóstico , Delitos Sexuais/prevenção & controle , Resultado do Tratamento
17.
J Pharm Sci ; 101(3): 1108-19, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22161641

RESUMO

Crystal morphology plays an important role in drug processing and delivery, which may be controlled during crystallisation. In this study, ibuprofen particles with different size and morphology were produced by controlled crystallisation in order to evaluate their impact on particle size reduction. Results suggest that the micronisation behaviour of ibuprofen was markedly influenced by the morphology and size of starting materials. It was possible to reduce the size of ibuprofen particles to sizes less than 5 µm during dry milling, which is markedly below the reported brittle-ductile transition size. Results also indicate that the particle size reduction mechanism is influenced by the size and morphology of the starting ibuprofen crystals. Dissolution behaviour of ibuprofen was shown to be influenced by the solid surface chemistry of micronised drug particles. The molecular modelling study provided deeper understanding of the experimental findings observed in this study.


Assuntos
Analgésicos não Narcóticos/química , Composição de Medicamentos/métodos , Ibuprofeno/química , Cristalização , Modelos Moleculares , Tamanho da Partícula , Solubilidade , Solventes/química
18.
J Control Release ; 149(2): 175-81, 2011 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-20946923

RESUMO

Recently, drug nanosuspensions have shown a potential for ophthalmic delivery. In this study, a hydrocortisone (HC) nanosuspension (NS) was developed using microfluidic nanoprecipitation as a recent, simple and cost-effective bottom-up technique of drug nanonization. For comparison, a second HC NS was prepared by top-down wet milling procedures. The produced nanosuspensions were characterized for particle size, shape and zeta potential. HC nanosuspensions of approximately 300nm particle size were produced by adjusting experimental conditions of the two processing techniques. Results of X-ray diffraction and differential scanning calorimetry revealed that HC maintained the crystalline structure upon milling, while predominant amorphous particles were generated after precipitation. Ocular bioavailability of HC nanosuspensions was assessed in albino rabbits using HC solution as a control. A sustained drug action was maintained up to 9h for the nanosuspensions compared to 5h for the drug solution. The precipitated and milled NS achieved comparable AUC(0-9h) values of 28.06±4.08 and 30.95±2.2, respectively, that were significantly (P<0.05) higher than that of HC solution (15.86±2.7). After 2 months storage at room temperature, the milled HC NS showed good stability with no discernable changes in particle size, whereas the particle size of the precipitated HC NS increased to 440nm.


Assuntos
Portadores de Fármacos/química , Composição de Medicamentos/métodos , Hidrocortisona/administração & dosagem , Microfluídica , Nanoestruturas/química , Nanotecnologia/métodos , Animais , Disponibilidade Biológica , Precipitação Química , Olho/metabolismo , Hidrocortisona/farmacocinética , Masculino , Soluções Oftálmicas , Tamanho da Partícula , Coelhos , Soluções , Suspensões , Molhabilidade
19.
Int J Pharm ; 375(1-2): 107-13, 2009 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-19481696

RESUMO

In this work, the possibility of bottom-up creation of a relatively stable aqueous hydrocortisone nanosuspension using microfluidic reactors was examined. The first part of the work involved a study of the parameters of the microfluidic precipitation process that affect the size of generated drug particles. These parameters included flow rates of drug solution and antisolvent, microfluidic channel diameters, microreactors inlet angles and drug concentrations. The experimental results revealed that hydrocortisone nano-sized dispersions in the range of 80-450 nm were obtained and the mean particle size could be changed by modifying the experimental parameters and design of microreactors. The second part of the work studied the possibility of preparing a hydrocortisone nanosuspension using microfluidic reactors. The nano-sized particles generated from a microreactor were rapidly introduced into an aqueous solution of stabilizers stirred at high speed with a propeller mixer. A tangential flow filtration system was then used to concentrate the prepared nanosuspension. The nanosuspension produced was then characterized using photon correlation spectroscopy (PCS), Zeta potential measurement, transmission electron microscopy (TEM), differential scanning calorimetry (DSC) and X-ray analysis. Results showed that a narrow sized nanosuspension composed of amorphous spherical particles with a mean particle size of 500+/-64 nm, a polydispersity index of 0.21+/-0.026 and a zeta potential of -18+/-2.84 mV was obtained. Physical stability studies showed that the hydrocortisone nanosuspension remained homogeneous with slight increase in mean particle size and polydispersity index over a 3-month period.


Assuntos
Anti-Inflamatórios/administração & dosagem , Excipientes/química , Hidrocortisona/administração & dosagem , Nanopartículas , Anti-Inflamatórios/química , Precipitação Química , Química Farmacêutica , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Hidrocortisona/química , Microfluídica/métodos , Nanotecnologia , Tamanho da Partícula , Solventes/química , Suspensões
20.
Eur J Pharm Sci ; 37(3-4): 514-22, 2009 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-19406230

RESUMO

This study employs artificial neural networks (ANNs) to create a model to identify relationships between variables affecting drug nanoprecipitation using microfluidic reactors. The input variables examined were saturation levels of prednisolone, solvent and antisolvent flow rates, microreactor inlet angles and internal diameters, while particle size was the single output. ANNs software was used to analyse a set of data obtained by random selection of the variables. The developed model was then assessed using a separate set of validation data and provided good agreement with the observed results. The antisolvent flow rate was found to have the dominant role on determining final particle size.


Assuntos
Anti-Inflamatórios/química , Prednisolona/química , Algoritmos , Inteligência Artificial , Técnicas Analíticas Microfluídicas , Modelos Químicos , Modelos Estatísticos , Redes Neurais de Computação , Tamanho da Partícula , Solubilidade
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