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1.
Nature ; 610(7932): 513-518, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36224387

RESUMO

As the United Nations develops a post-2020 global biodiversity framework for the Convention on Biological Diversity, attention is focusing on how new goals and targets for ecosystem conservation might serve its vision of 'living in harmony with nature'1,2. Advancing dual imperatives to conserve biodiversity and sustain ecosystem services requires reliable and resilient generalizations and predictions about ecosystem responses to environmental change and management3. Ecosystems vary in their biota4, service provision5 and relative exposure to risks6, yet there is no globally consistent classification of ecosystems that reflects functional responses to change and management. This hampers progress on developing conservation targets and sustainability goals. Here we present the International Union for Conservation of Nature (IUCN) Global Ecosystem Typology, a conceptually robust, scalable, spatially explicit approach for generalizations and predictions about functions, biota, risks and management remedies across the entire biosphere. The outcome of a major cross-disciplinary collaboration, this novel framework places all of Earth's ecosystems into a unifying theoretical context to guide the transformation of ecosystem policy and management from global to local scales. This new information infrastructure will support knowledge transfer for ecosystem-specific management and restoration, globally standardized ecosystem risk assessments, natural capital accounting and progress on the post-2020 global biodiversity framework.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Política Ambiental , Biodiversidade , Biota , Conservação dos Recursos Naturais/legislação & jurisprudência , Conservação dos Recursos Naturais/métodos , Política Ambiental/legislação & jurisprudência , Política Ambiental/tendências , Objetivos , Nações Unidas , Animais
2.
Int J Mol Sci ; 25(8)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38673856

RESUMO

Immune response to biomaterials, which is intimately related to their surface properties, can produce chronic inflammation and fibrosis, leading to implant failure. This study investigated the development of magnetic nanoparticles coated with silica and incorporating the anti-inflammatory drug naproxen, aimed at multifunctional biomedical applications. The synthesized nanoparticles were characterized using various techniques that confirmed the presence of magnetite and the formation of a silica-rich bioactive glass (BG) layer. In vitro studies demonstrated that the nanoparticles exhibited bioactive properties, forming an apatite surface layer when immersed in simulated body fluid, and biocompatibility with bone cells, with good viability and alkaline phosphatase activity. Naproxen, either free or encapsulated, reduced nitric oxide production, an inflammatory marker, while the BG coating alone did not show anti-inflammatory effects in this study. Overall, the magnetic nanoparticles coated with BG and naproxen showed promise for biomedical applications, especially anti-inflammatory activity in macrophages and in the bone field, due to their biocompatibility, bioactivity, and osteogenic potential.


Assuntos
Materiais Revestidos Biocompatíveis , Vidro , Nanopartículas de Magnetita , Naproxeno , Naproxeno/farmacologia , Naproxeno/química , Vidro/química , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Nanopartículas de Magnetita/química , Animais , Camundongos , Humanos , Óxido Nítrico/metabolismo , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Dióxido de Silício/química , Sobrevivência Celular/efeitos dos fármacos , Células RAW 264.7 , Osteogênese/efeitos dos fármacos
3.
Int J Mol Sci ; 24(6)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36982196

RESUMO

Many activities have been described for propolis, including, antiviral, antibacterial, antifungal, anti-inflammatory, immunoregulatory, antioxidant and wound healing properties. Recently, propolis has been highlighted due to its potential application in the pharmaceutical and cosmetic industries, motivating a better understanding of its antioxidant and anti-inflammatory activities. Propolis and its main polyphenolic compounds presented high antioxidant activity, and effectiveness as broad spectrum UVB and UVA photoprotection sunscreens. Through a qualitative phytochemical screening, the ethanolic red propolis extracts (EEPV) (70% at room temperature and 70% at a hot temperature) presented a positive result for flavonoids and terpenoids. It presented an antioxidant activity for reducing 50% of DPPH of 17 and 12 µg/mL for extraction at room temperature and at a hot temperature, respectively. The UPLC-QTOF-MS/MS analysis allowed the annotation of 40 substances for EEPV-Heated and 42 substances for EEPV-Room Temperature. The IC50 results of the ABTS scavenging activity was 4.7 µg/mL for both extractions, at room temperature and at a hot temperature. Additionally, we also evaluated the cytotoxic profile of propolis extracts against macrophage (RAW 264.7 cells) and keratinocytes (HaCaT cells), which showed non-cytotoxic doses in cell viability assays even after a long period of exposure. In addition, propolis extracts showed antibacterial activity for Gram-positive bacteria (Staphylococcus aureus and Staphylococcus epidermidis), demonstrating potential biological activity for the creation of formulations aimed at disease control and prevention.


Assuntos
Anti-Infecciosos , Ascomicetos , Própole , Própole/farmacologia , Própole/química , Antioxidantes/farmacologia , Antioxidantes/química , Protetores Solares/farmacologia , Espectrometria de Massas em Tandem , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/química
4.
Int J Mol Sci ; 25(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38203662

RESUMO

Cancer is one of the deadliest diseases worldwide and has been responsible for millions of deaths. However, developing a satisfactory smart multifunctional material combining different strategies to kill cancer cells poses a challenge. This work aims at filling this gap by developing a composite material for cancer treatment through hyperthermia and drug release. With this purpose, magnetic nanoparticles were coated with a polymer matrix consisting of poly (L-co-D,L lactic acid-co-trimethylene carbonate) and a poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymer. High-resolution transmission electron microscopy and selected area electron diffraction confirmed magnetite to be the only iron oxide in the sample. Cytotoxicity and heat release assays on the hybrid nanoparticles were performed here for the first time. The heat induction results indicate that these new magnetic hybrid nanoparticles are capable of increasing the temperature by more than 5 °C, the minimal temperature rise required for being effectively used in hyperthermia treatments. The biocompatibility assays conducted under different concentrations, in the presence and in the absence of an external alternating current magnetic field, did not reveal any cytotoxicity. Therefore, the overall results indicate that the investigated hybrid nanoparticles have a great potential to be used as carrier systems for cancer treatment by hyperthermia.


Assuntos
Calefação , Hipertermia Induzida , Humanos , Hipertermia , Eletricidade
5.
Molecules ; 28(23)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38067542

RESUMO

Chagas disease (CD) is a worldwide public health problem, and the drugs available for its treatment have severe limitations. Red propolis is a natural extract known for its high content of phenolic compounds and for having activity against T. cruzi. The aim of this study was to investigate the trypanocidal potential of red propolis to isolate, identify, and indicate the mode of action of the bioactive compounds. The results revealed that the total phenolic content was 15.4 mg GAE/g, and flavonoids were 7.2 mg QE/g. The extract was fractionated through liquid-liquid partitioning, and the trypanocidal potential of the samples was evaluated using the epimastigote forms of the Y strain of T. cruzi. In this process, one compound was characterized by MS, 1H, and 13C NMR and identified as vestitol. Cytotoxicity was evaluated employing MRC-5 fibroblasts and H9C2 cardiomyocytes, showing cytotoxic concentrations above 15.62 µg/mL and 31.25 µg/mL, respectively. In silico analyses were applied, and the data suggested that the substance had a membrane-permeation-enhancing effect, which was confirmed through an in vitro assay. Finally, a molecular docking analysis revealed a higher affinity of vestitol with farnesyl diphosphate synthase (FPPS). The identified isoflavan appears to be a promising lead compound for further development to treat Chagas disease.


Assuntos
Doença de Chagas , Própole , Tripanossomicidas , Trypanosoma cruzi , Humanos , Própole/química , Simulação de Acoplamento Molecular , Doença de Chagas/tratamento farmacológico , Flavonoides/química , Extratos Vegetais/farmacologia , Tripanossomicidas/química
6.
Conserv Biol ; 35(6): 1882-1893, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33728690

RESUMO

There has been much recent interest in the concept of rewilding as a tool for nature conservation, but also confusion over the idea, which has limited its utility. We developed a unifying definition and 10 guiding principles for rewilding through a survey of 59 rewilding experts, a summary of key organizations' rewilding visions, and workshops involving over 100 participants from around the world. The guiding principles convey that rewilding exits on a continuum of scale, connectivity, and level of human influence and aims to restore ecosystem structure and functions to achieve a self-sustaining autonomous nature. These principles clarify the concept of rewilding and improve its effectiveness as a tool to achieve global conservation targets, including those of the UN Decade on Ecosystem Restoration and post-2020 Global Biodiversity Framework. Finally, we suggest differences in rewilding perspectives lie largely in the extent to which it is seen as achievable and in specific interventions. An understanding of the context of rewilding projects is the key to success, and careful site-specific interpretations will help achieve the aims of rewilding.


Recientemente ha habido mucho interés por el concepto de retorno a la vida silvestre como herramienta para la conservación de la naturaleza, pero también ha habido confusión por la idea que ha limitado su utilidad. Desarrollamos una definición unificadora y diez principios básicos para el retorno a la vida silvestre por medio de encuestas a 59 expertos en retorno a la vida silvestre, un resumen de las visiones de las organizaciones más importantes para el retorno a la vida silvestre y talleres que involucraron a más de 100 participantes de todo el mundo. Los principios básicos transmiten que el retorno a la vida silvestre existe en un continuo de escala, conectividad y nivel de influencia humana y que su objetivo es restaurar la estructura y las funciones del ecosistema para lograr una naturaleza autónoma autosustentable. Estos principios aclaran el concepto del retorno a la vida silvestre e incrementan su efectividad como herramienta para lograr los objetivos mundiales de conservación, incluyendo aquellos de la Década de la ONU para la Restauración de Ecosistemas y el Marco de Trabajo de la Biodiversidad Global post 2020. Finalmente, sugerimos que las diferencias en las perspectivas del retorno a la vida silvestre yacen principalmente en el grado al que es visto como factible y en intervenciones específicas. Un entendimiento del contexto de los proyectos de retorno a la vida silvestre es importante para el éxito, y las interpretaciones específicas de sitio ayudarán a lograr las metas del retorno a la vida silvestre. Principios Básicos para el Retorno a la Vida Silvestre.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Humanos
7.
AIDS Behav ; 23(6): 1541-1551, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30652206

RESUMO

Comprehensive care for sexual and reproductive health (SRH) and social needs for women living with HIV remains limited globally. We aimed to assess trends in baseline sociodemographic, clinical, sexual, and reproductive characteristics among a cohort of HIV-infected women in Rio de Janeiro from 1996 to 2016. Participants were stratified into four time periods based on year of enrollment; we compared cross-sectional data from each period. Of 1361 participants (median age 36), most were black or mixed race (60.1%), unemployed (52.1%), and without secondary education (54%). Adolescent pregnancy was common (51.5%), and 18.3% reported sexual debut at < 15 years old. Nearly half (45.2%) had < 5 lifetime sexual partners, yet prior syphilis and oncogenic human papillomavirus prevalence were 10.9% and 43.1%, respectively. Lifetime prevalence of induced abortion was 30.3%, and 16% used no contraceptive method. Future research should explore interactions between social vulnerability, HIV, and poor SRH outcomes and healthcare models to alleviate these disparities.


Assuntos
Infecções por HIV/epidemiologia , Pobreza/estatística & dados numéricos , Saúde Reprodutiva , Comportamento Sexual/estatística & dados numéricos , Adolescente , Adulto , Brasil/epidemiologia , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Gravidez , Prevalência , Populações Vulneráveis
8.
AAPS PharmSciTech ; 19(3): 1287-1296, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29318467

RESUMO

Several authors have studied the release profile of drugs incorporated in different devices. However, to the best of our knowledge, although many studies have been done on the release of tetracycline, in these release devices, no study has investigated if the released compound is actually the tetracycline, or, instead, a degraded product. This approach is exploited here. In this work, we analyse the influence of two drying methods on the tetracycline delivery behaviour of synthesised glasses using the sol-gel process. We compare the drying methods results using both theoretical models and practical essays, and analyse the chemical characteristic of the released product in order to verify if it remains tetracycline. Samples were freeze-dried or dried in an oven at 37°C and characterised by several methods such as Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TG), differential thermogravimetric analysis (DTG), differential thermal analyses (DTA) and gas adsorption analysis (BET). The released concentration of tetracycline hydrochloride was studied as a function of time, and it was measured by ultraviolet spectrophotometry in the tetracycline wavelength. The drug delivery profiles were reasonably consistent with a diffusion model analysis. In addition, we observed higher release rates for the freeze-dried compared to those dried in an oven at 37°C. This higher release can be attributed to larger pore size for the freeze-dried sample systems with tetracycline, which promoted more water penetration, improving the drug diffusion. The analysis of the solution obtained in the release tests using high-performance liquid chromatography- mass spectrometry (HPLC-MS) confirmed that tetracycline was being released.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Tetraciclinas/síntese química , Antibacterianos/administração & dosagem , Antibacterianos/síntese química , Antibacterianos/farmacocinética , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/síntese química , Preparações de Ação Retardada/farmacocinética , Difusão , Composição de Medicamentos/métodos , Liofilização/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Tetraciclinas/administração & dosagem , Tetraciclinas/farmacocinética
9.
Cultur Divers Ethnic Minor Psychol ; 23(2): 209-219, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27429064

RESUMO

OBJECTIVES: Prejudice against Native Americans as an overall group generally polarizes into positive and negative stereotypic extremes, but distinct subgroups may explain this variability. METHOD: Using college student samples (Study 1), a preliminary study identified common Native American subgroups and then a main study (N = 153, 74% women, 73% White, mean age = 19 years) had participants rate these subgroups on basic dimensions of stereotype content (i.e., warmth and competence), elicited emotions (e.g., admiration, contempt), and elicited behaviors (e.g., facilitation, harm). In Study 2, these preliminary study and main study procedures were replicated using nationwide samples (main study: N = 139, 51% women, 78% White, mean age = 35 years). RESULTS: For the most part, similar Native American subgroups emerged in both samples. Using the stereotype content model (SCM; Fiske, Cuddy, Glick, & Xu, 2002), the subgroups were found to vary along a competence-by-warmth space. The majority of subgroups (e.g., alcoholics, lazy) were judged low in both competence and warmth. Additional subgroups (e.g., casino operators, warriors) were ambivalently judged as high on competence but low on warmth. Subgroups perceived as high in both competence and warmth elicited more admiration, those low in both competence and warmth elicited more contempt, those high in competence elicited more passive facilitation and less passive harm, and those high in warmth elicited more active facilitation and less active harm. CONCLUSIONS: Native American stereotypes are apparently characterized by both noble and ignoble subgroups, highlighting the importance of studying stereotypes at the subgroup level. (PsycINFO Database Record


Assuntos
Indígenas Norte-Americanos/psicologia , Estereotipagem , Estudantes/psicologia , Adulto , Emoções , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autoimagem , Percepção Social , Adulto Jovem
10.
BMC Cancer ; 15: 478, 2015 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-26100400

RESUMO

BACKGROUND: In Brazil, the rate of cervical cancer remains high despite the availability of screening programs. With ongoing vaccine development and implementation, information on the prevalence of specific HPV types is needed, particularly among high-risk populations, such as HIV-infected women. METHODS: We performed a study of HIV-infected women in Rio de Janeiro, Brazil, who underwent cervical HPV genotype testing between 2005-2013. We examined the prevalence of high-risk HPV types and the patterns of high-risk HPV type clustering. Using logarithmic binomial regression, we estimated the risk of abnormal cytology by HPV genotype result. RESULTS: Of the 562 women included, 498 (89 %) had at least one HPV type detected. 364 women (65 %) had at least one high-risk HPV type detected and 181 (32 %) had more than one high-risk type detected. HPV 58 was the most frequent HPV type detected overall (prevalence 19.8 % [95 % confidence interval 16.4-23.1]), followed by HPV 53 (prevalence 15.5 % [12.5-18.5]) and HPV 16 (prevalence 13 % [10.2-15.8]). Women infected with more than one high-risk HPV type were younger, had lower CD4+ lymphocyte counts, and were more likely to be infected with HPV 16 or 18. In adjusted analyses, presence of more than one high-risk HPV type was associated with a two-fold increased risk of abnormal cytology after adjusting for presence of individual high-risk type, age, and CD4+ lymphocyte count (adjusted prevalence ratios 1.88-2.07, all p <0.001). No single high-risk HPV type was statistically associated with abnormal cytology after adjusting for the presence of more than one high-risk HPV type. CONCLUSIONS: In the largest study of cervical HPV genotypes among HIV-infected women in Latin America, infection by high-risk HPV types other than 16 or 18 and infection by more than one high-risk HPV types were common. Infection by more than one high-risk type was more strongly associated with abnormal cervical cytology than any individual high-risk HPV type, highlighting the need for multi-valent HPV vaccines.


Assuntos
Infecções por HIV/epidemiologia , Infecções por Papillomavirus/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Adulto , Brasil/epidemiologia , Estudos Transversais , Feminino , Infecções por HIV/complicações , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Pessoa de Meia-Idade , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero/complicações , Neoplasias do Colo do Útero/imunologia , Neoplasias do Colo do Útero/virologia
11.
Am J Obstet Gynecol ; 212(6): 765.e1-765.e13, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25557206

RESUMO

OBJECTIVE: This study sought to investigate the age at natural menopause and its predictors in a cohort of human immunodeficiency virus (HIV)-infected women in Rio de Janeiro, Brazil. STUDY DESIGN: HIV-infected women ≥30 years of age were included. Menopause was defined as having ≥1 year since the last menstrual period. Early age at natural menopause was defined as the onset of menopause at ≤45 years of age. Multivariate Cox proportional hazards analysis was applied. RESULTS: A total of 667 women were included, and the median age at baseline was 34.9 years (interquartile range, 30.9-40.5 years). In all, 507 (76%) women were premenopausal, and 160 (24%) reached menopause during the observational period; of these, 36 of 160 (27%) had early menopause. The median age at natural menopause was 48 years (interquartile range, 45-50 years). Menarche at <11 years of age (hazard ratio [HR], 2.03; 95% confidence interval [CI], 1.23-3.37), cigarette smoking during the observational period (HR, 1.59; 95% CI, 1.08-2.33), chronic hepatitis C virus (HCV) infection (HR, 2.53; 95% CI, 1.27-5.07), and CD4 count <50 cells/mm(3) (HR, 3.07; 95% CI, 1.07-8.80) were significantly associated with an earlier age at natural menopause. The magnitudes of the effects of menarche at <11 years of age (HR, 2.7; 95% CI, 1.23-5.94), cigarette smoking during the observational period (HR, 3.00; 95% CI, 1.39-6.45), chronic HCV infection (HR, 6.26; 95% CI, 2.12-18.52), and CD4 count <50 cells/mm(3) (HR, 6.64; 95% CI, 1.91-23.20) were much higher and significantly associated with early natural menopause. CONCLUSION: Early natural menopause was frequent among the HIV-infected women. In addition to menarche and cigarette smoking, which are menopausal factors among women in general, HIV-related immunodeficiency and chronic HCV were additional predictors for an earlier age at natural menopause. Adequate management of HIV in women is critical, as early onset of menopause has been associated with increased morbidity and mortality.


Assuntos
Infecções por HIV/fisiopatologia , Menopausa Precoce , Adulto , Fatores Etários , Estudos de Coortes , Feminino , Humanos , Estudos Prospectivos
12.
Nat Ecol Evol ; 8(4): 614-621, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38332025

RESUMO

The Kunming-Montreal Global Biodiversity Framework (GBF) of the UN Convention on Biological Diversity set the agenda for global aspirations and action to reverse biodiversity loss. The GBF includes an explicit goal for maintaining and restoring biodiversity, encompassing ecosystems, species and genetic diversity (goal A), targets for ecosystem protection and restoration and headline indicators to track progress and guide action1. One of the headline indicators is the Red List of Ecosystems2, the global standard for ecosystem risk assessment. The Red List of Ecosystems provides a systematic framework for collating, analysing and synthesizing data on ecosystems, including their distribution, integrity and risk of collapse3. Here, we examine how it can contribute to implementing the GBF, as well as monitoring progress. We find that the Red List of Ecosystems provides common theory and practical data, while fostering collaboration, cross-sector cooperation and knowledge sharing, with important roles in 16 of the 23 targets. In particular, ecosystem maps, descriptions and risk categories are key to spatial planning for halting loss, restoration and protection (targets 1, 2 and 3). The Red List of Ecosystems is therefore well-placed to aid Parties to the GBF as they assess, plan and act to achieve the targets and goals. We outline future work to further strengthen this potential and improve biodiversity outcomes, including expanding spatial coverage of Red List of Ecosystems assessments and partnerships between practitioners, policy-makers and scientists.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Medição de Risco
13.
NanoImpact ; 35: 100517, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38848992

RESUMO

Superparamagnetic iron oxide nanoparticles (SPIONs) have gained significant attention in biomedical research due to their potential applications. However, little is known about their impact and toxicity on testicular cells. To address this issue, we conducted an in vitro study using primary mouse testicular cells, testis fragments, and sperm to investigate the cytotoxic effects of sodium citrate-coated SPIONs (Cit_SPIONs). Herein, we synthesized and physiochemically characterized the Cit_SPIONs and observed that the sodium citrate diminished the size and improved the stability of nanoparticles in solution during the experimental time. The sodium citrate (measured by thermogravimetry) was biocompatible with testicular cells at the used concentration (3%). Despite these favorable physicochemical properties, the in vitro experiments demonstrated the cytotoxicity of Cit_SPIONs, particularly towards testicular somatic cells and sperm cells. Transmission electron microscopy analysis confirmed that Leydig cells preferentially internalized Cit_SPIONs in the organotypic culture system, which resulted in alterations in their cytoplasmic size. Additionally, we found that Cit_SPIONs exposure had detrimental effects on various parameters of sperm cells, including motility, viability, DNA integrity, mitochondrial activity, lipid peroxidation (LPO), and ROS production. Our findings suggest that testicular somatic cells and sperm cells are highly sensitive and vulnerable to Cit_SPIONs and induced oxidative stress. This study emphasizes the potential toxicity of SPIONs, indicating significant threats to the male reproductive system. Our findings highlight the need for detailed development of iron oxide nanoparticles to enhance reproductive nanosafety.

14.
Polymers (Basel) ; 15(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37299312

RESUMO

In recent years, polymeric materials have been gaining prominence in studies of controlled release systems to obtain improvements in drug administration. These systems present several advantages compared with conventional release systems, such as constant maintenance in the blood concentration of a given drug, greater bioavailability, reduction of adverse effects, and fewer dosages required, thus providing a higher patient compliance to treatment. Given the above, the present work aimed to synthesize polymeric matrices derived from polyethylene glycol (PEG) capable of promoting the controlled release of the drug ketoconazole in order to minimize its adverse effects. PEG 4000 is a widely used polymer due to its excellent properties such as hydrophilicity, biocompatibility, and non-toxic effects. In this work, PEG 4000 and derivatives were incorporated with ketoconazole. The morphology of polymeric films was observed by AFM and showed changes on the film organization after drug incorporation. In SEM, it was possible to notice spheres that formed in some incorporated polymers. The zeta potential of PEG 4000 and its derivatives was determined and suggested that the microparticle surfaces showed a low electrostatic charge. Regarding the controlled release, all the incorporated polymers obtained a controlled release profile at pH 7.3. The release kinetics of ketoconazole in the samples of PEG 4000 and its derivatives followed first order for PEG 4000 HYDR INCORP and Higuchi for the other samples. Cytotoxicity was determined and PEG 4000 and its derivatives were not cytotoxic.

15.
Braz J Infect Dis ; 27(4): 102779, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37230150

RESUMO

Syndemic psychosocial and reproductive factors affecting women's retention in HIV care remain understudied. We analyzed correlates of non-retention in a cohort of women with HIV in Brazil from 2000‒2015. Participants self-reported exposure to physical/sexual violence, illicit drug use, adolescent pregnancy, or induced abortion. Lifetime history of these psychosocial stressors were used to create a syndemic score based on the presence or absence of these conditions. All dichotomous variables were summed (range 0 to 4), with greater scores indicating more syndemic factors experienced. Logistic regression models identified predictors of non-retention, defined as < 2 HIV viral load or CD4 results within the first year of enrollment. Of 915 women, non-retention was observed for 18%. Prevalence of syndemic factors was adolescent pregnancy (53.2%), physical/sexual violence (38.3%), induced abortion (27.3%), and illicit drug use (17.2%); 41.2% experienced ≥ 2 syndemic conditions. Syndemic scores of 2 and 3 were associated with non-retention, as well as low education, years with HIV and seroprevalent syphilis. Psychosocial and reproductive syndemics can limit women's retention in HIV care. Syphilis infection predicted non-retention and could be explored as a syndemic factor in future studies.


Assuntos
Infecções por HIV , Drogas Ilícitas , Retenção nos Cuidados , Transtornos Relacionados ao Uso de Substâncias , Sífilis , Gravidez , Adolescente , Humanos , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/psicologia , Sindemia , Sífilis/epidemiologia , Brasil/epidemiologia , Saúde Reprodutiva , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/psicologia
16.
J Alzheimers Dis ; 95(3): 1091-1106, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37638430

RESUMO

BACKGROUND: The SARS-CoV2 global pandemic impacted participants in the Alzheimer's Prevention Initiative (API) Autosomal Dominant Alzheimer's Disease (ADAD) clinical trial, who faced three stressors: 1) fear of developing dementia; 2) concerns about missing treatment; and 3) risk of SARS-CoV2 infection. OBJECTIVE: To describe the frequency of psychological disorders among the participants of the API ADAD Colombia clinical study, treated by a holistic mental health team during the COVID-19 pandemic. The extent of use of mental health team services was explored considering different risk factors, and users and non-users of these services were compared. METHODS: Participants had free and optional access to psychology and psychiatry services, outside of the study protocol. Descriptive statistics was used to analyze the frequency of the mental health difficulties. A multivariable logistic regression model has been used to assess associations with using this program. RESULTS: 66 participants were treated by the Mental Health Team from March 1, 2020, to December 31, 2020. Before and after the start of the pandemic, the most common psychological problems were anxiety (36.4% before, 63.6% after) and depression (34.8% before, 37.9% after). 70% of users assisted by psychology and 81.6% of those assisted by psychiatry felt that the services were useful for them. Female sex, depression, and anxiety before the pandemic were positively associated with being assisted by either psychology or psychiatry, while the association with hyperlipidemia was negative. CONCLUSIONS: A holistic mental health program, carried out in the context of a study, could mitigate psychopathology during pandemics such as COVID-19.


Assuntos
Doença de Alzheimer , COVID-19 , Humanos , Feminino , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/prevenção & controle , Doença de Alzheimer/psicologia , SARS-CoV-2 , Pandemias , Colômbia/epidemiologia , RNA Viral , Ansiedade/epidemiologia , Depressão
17.
J Nanobiotechnology ; 10: 13, 2012 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-22439913

RESUMO

BACKGROUND: Dengue is a major public health problem worldwide, especially in the tropical and subtropical regions of the world. Infection with a single Dengue virus (DENV) serotype causes a mild, self-limiting febrile illness called dengue fever. However, a subset of patients experiencing secondary infection with a different serotype progresses to the severe form of the disease, dengue hemorrhagic fever/dengue shock syndrome. Currently, there are no licensed vaccines or antiviral drugs to prevent or treat dengue infections. Biodegradable nanoparticles coated with proteins represent a promising method for in vivo delivery of vaccines. FINDINGS: Here, we used a murine model to evaluate the IgG production after administration of inactivated DENV corresponding to all four serotypes adsorbed to bovine serum albumin nanoparticles. This formulation induced a production of anti-DENV IgG antibodies (p < 0.001). However, plaque reduction neutralization assays with the four DENV serotypes revealed that these antibodies have no neutralizing activity in the dilutions tested. CONCLUSIONS: Our results show that while the nanoparticle system induces humoral responses against DENV, further investigation with different DENV antigens will be required to improve immunogenicity, epitope specicity, and functional activity to make this platform a viable option for DENV vaccines.


Assuntos
Anticorpos Antivirais/biossíntese , Vírus da Dengue/imunologia , Nanopartículas , Animais , Vírus da Dengue/crescimento & desenvolvimento , Camundongos , Microscopia Eletrônica de Varredura , Testes de Neutralização , Ensaio de Placa Viral
18.
Rheumatol Int ; 32(4): 863-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21221593

RESUMO

With the purpose of contributing to a better knowledge of the APCs functional activity in SLE, we evaluated the distribution and functional ability to produce pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6 and IL-12) of peripheral blood (PB) monocytes and DC (tDC), particularly myeloid (mDC) and CD14(-/low)CD16(+) DC subpopulations comparing them with those obtained from healthy individuals. The study was performed in 34 SLE patients with diverse disease activity scores (SLEDAI) and 13 healthy age- and sex-matched controls (NC). Our results show an overall decrease in absolute number and relative frequency of tDC in SLE patients with active disease when compared to those with inactive disease and NC, although this decrease did not seem to have an effect on the distribution of PB DC subsets. The monocytes number in SLE patients was similar to those found in NC, whereas a higher frequency of monocytes producing cytokines as well as the amount of each cytokine per cell found without stimulation was particularly observed in those patients with active disease. After stimulation, we observed a higher frequency of IL-12-producing monocytes in active SLE patients. On the other hand, we found among DCs higher frequencies of cytokine-producing CD14(-/low)CD16(+) DCs and a higher amount of cytokines produced per cell, particularly in active disease. These findings support an increased production of inflammatory cytokines by APCs in active SLE, mostly associated with alterations in CD14(-/low)CD16(+) DC subset homeostasis that might contribute to explain the dynamic role of these cells in disease pathogenesis.


Assuntos
Citocinas/biossíntese , Células Dendríticas/imunologia , Lúpus Eritematoso Sistêmico/sangue , Monócitos/imunologia , Adulto , Citocinas/sangue , Feminino , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade
19.
Sci Rep ; 12(1): 13425, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35927566

RESUMO

Although Bioactive Glasses (BGs) have been progressively optimized, their preparation often still involves the use of toxic reagents and high calcination temperatures to remove organic solvents. In the present work, these synthesis related drawbacks were overcome by treating the ashes from the Equisetum hyemale plant in an ethanol/water solution to develop a bioactive composite [glass/carbon (BG-Carb)]. The BG-Carb was characterized by scanning electron microscopy, and transmission electron microscopy; and its chemical composition was assessed by inductively coupled plasma-optical emission spectroscopy. Brunauer-Emmett-Teller gas adsorption analysis showed a specific surface area of 121 m2 g-1. The formation of hydroxyapatite (HA) surface layer in vitro was confirmed by Fourier-transform infrared spectroscopy analysis before and after immersion in simulated body fluid (SBF) solution. The Rietveld refinement of the XRD patterns and selected area electron diffraction analyses confirmed HA in the sample even before immersing it in SBF solution. However, stronger evidences of the presence of HA were observed after immersion in SBF solution due to the surface mineralization. The BG-Carb samples showed no cytotoxicity on MC3T3-E1 cells and osteo-differentiation capacity similar to the positive control. Altogether, the BG-Carb material data reveals a promising plant waste-based candidate for hard and soft tissue engineering.


Assuntos
Materiais Biocompatíveis , Equisetum , Materiais Biocompatíveis/química , Durapatita/química , Vidro/química , Microscopia Eletrônica de Varredura , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Engenharia Tecidual/métodos , Difração de Raios X
20.
J Mech Behav Biomed Mater ; 136: 105511, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36252425

RESUMO

OBJECTIVES: We aimed to optimize the mechanical and biological properties of a conventional methacrylate-based dental polymer by loading it with double- and triple-walled carbon nanotubes as growth (DTWCNTG). METHODS: A formulation of bisphenol A-glycidyl methacrylate and triethylene glycol dimethacrylate (mass ratio = 2:1) was mixed with DTWCNTG at concentrations of 0.0% (control), 0.001%, 0.005%, and 0.010%. The concentrations were physicochemical and morphologically evaluated, and antibacterial activity was assessed by seeding a Streptococcus mutans strain (ATCC 25175) on the experimental polymeric surfaces. Cellular survival and osteodifferentiation were evaluated in epithelial (HaCat) and preosteoblast cells (MC3T3-E1). RESULTS: The 0.001% DTWCNTG concentration yielded higher compressive strength, elastic modulus, flexural strength, flexural modulus, water sorption, and solubility than the control. The degree of conversion and color did not significantly change with a low amount of DTWCNTG incorporated into the polymer. Antibacterial activity significantly improved when tested on the 0.001% DTWCNTG discs. No groups showed cytotoxicity in a short-term analysis and adding DTWCNTG favored MC3T3-E1 mineralization over the control, particularly in the 0.001% formulation. SIGNIFICANCE: The micro-addition of 0.001% DTWCNTG confers mechanical resistance, antimicrobial properties, and bioactivity to methacrylate-based polymers without significantly compromising color. Incorporating DTWCNTG improved dental composite properties and could be a biomodified material for minimally invasive procedures.


Assuntos
Metacrilatos , Nanotubos de Carbono , Metacrilatos/farmacologia , Metacrilatos/química , Resinas Compostas/química , Polímeros/farmacologia , Teste de Materiais , Bis-Fenol A-Glicidil Metacrilato/química , Ácidos Polimetacrílicos/química , Polietilenoglicóis/química , Antibacterianos/farmacologia , Antibacterianos/química
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