Gene therapy is a promising tool for the treatment of ocular diseases. Nevertheless, there are some import limitations, especially related to the ocular route and the characteristics of nucleic acids that must be overcome to ensure the success of the therapy. In this context, nanotechnology-based carriers such as nanoemulsions, nanoparticles, dendrimers and liposomes have risen as a promising vehicle for the protection of genetic material for vectoring the target cells. The success of such approach is closely related to the judicious selection of the biomaterial, where chemical structure and intermolecular interactions play a major role. So, this manuscript reviews some of the most important biomaterials, lipid and polymeric origin, employed in the manufacture of nanotechnologic carriers for ocular gene therapy involving interfering RNA (siRNA), antisense oligonucleotide (AS-ON) and plasmid DNA (pDNA).

RESUMO Acanthamoeba é a mais comum ameba de vida livre no ambiente, pode atuar como um importante veículo para vários micro-organismos que vivem no mesmo ambiente, tais como vírus, e pode ser patogênica para humanos. Este estudo objetivou detectar e quantificar adenovírus humano (HAdV) em Acanthamoebas isoladas de amostras de águas coletadas de piscinas na cidade de Porto Alegre, no sul do Brasil. Amebas de vida livre do gênero Acanthamoeba foram isolados de amostras de água, e os isolados (n = 16) foram usados para investigar a ocorrência de HAdVs. Detecção de HAdV foi realizada usando reação em cadeia de polimerase quantitativa (qPCR) em tempo real. HAdVs foram detectados em 62.5% (10/16) dos isolados de Acanthamoeba, variando de 3.24 x 103 a 5.14 x 105 cópias de DNA por mililitro de isolado. As cargas virais de HAdV encontradas nesse estudo não são negligenciáveis, especialmente porque infecções por HAdV são associadas com diferentes doenças humanas, incluindo gastrenterites, doenças respiratórias e oculares. Este estudo reforça o conceito que Acanthamoeba poderia atuar com um reservatório e promover a transmissão de HAdV através da água.

ABSTRACT Acanthamoeba is the most common free-living environmental amoeba, it may serve as an important vehicle for various microorganisms living in the same environment, such as viruses, being pathogenic to humans. This study aimed to detect and quantify human adenoviruses (HAdV) in Acanthamoebas isolated from water samples collected from swimming pools in the city of Porto Alegre, Southern Brazil. Free-living amoebae of the genus Acanthamoeba were isolated from water samples, and isolates (n=16) were used to investigate the occurrence of HAdVs. HAdV detection was performed by quantitative real-time polymerase chain reaction (qPCR). HAdVs were detected in 62.5% (10/16) of Acanthamoeba isolates, ranging from 3.24x103 to 5.14x105 DNA copies per milliliter of isolate. HAdV viral loads found in this study are not negligible, especially because HAdV infections are associated with several human diseases, including gastroenteritis, respiratory distress, and ocular diseases. These findings reinforce the concept that Acanthamoeba may act as a reservoir and promote HAdV transmission through water.

Hortaliças minimamente processadas passam por várias etapas durante seu processamento, no qual ocorrem várias modificações de sua estrutura natural, todavia elas devem manter a mesma qualidade do produto não processado. O objetivo deste estudo foi quantificar microrganismos mesófilos e psicrótróficos, coliformes totais e fecais e verificar a presença de E. coli, parasitas e sujidades em hortaliças minimamente processadas prontas para consumo. Foram analisadas 56 amostras para mesófilos e psicrotróficos pelo método de contagem em placas, com média mensal 4,7x10(5) a 1,6x10(8) UFC/g e de 7,9x10(6) a 2,7x10(8) UFC/g, respectivamente. Os coliformes foram analisados pela técnica dos tubos múltiplos, onde coliformes totais variaram de <3 a ³ 2,4x10(4) NMP/g e coliformes fecais, de <3 a 1,1x10(4) NMP/g, e E. coli foi observada em oito amostras. De 52 amostras, 8 (15,3%) apresentaram oocistos de Eimeria spp. Sujidades, como fragmentos de insetos e ácaros jovens foram encontrados. Contaminação de origem fecal foi verificada no presente estudo, sugerindo falhas nas etapas do processamento das hortaliças, ou que o solo ou a água de irrigação também poderiam ser fontes de disseminação destes microrganismos.

Minimally processed vegetables go through various steps during their preparation, with many modifications to their natural structure. However, they must maintain the same quality as the fresh produce. The aim of the present study was to quantify mesophilic and psychrotrophic microorganisms and total and faecal coliforms, and to assess the presence of Escherichia coli, parasites, and dirt material in ready-to-eat minimally processed vegetables. Fifty-six samples of minimally processed vegetables were analysed for the presence of mesophilic and psychrotrophic microorganisms by the plate-count method. Monthly means ranged from 4.7x10(5) to 1.6x10(8) CFU/g and from 7.9x10(6) to 2.7x10(8) CFU/g, respectively for mesophilic and psychrotrophic microorganisms. Coliforms were analysed by the multiple-tube method; total coliforms ranged from <3 to ³ 2.4x10(4) MPN/g and faecal coliforms from <3 to 1.1x10(4) MPN/g. Escherichia coli was detected in eight samples. Out of 52 samples, eight (15.3%) contained oocysts of Eimeria spp.. Dirt matter, such as insect body parts and young mites, was also found. Contamination of faecal origin was observed in these samples, suggesting that either the sanitisation of the product was unsuccessful, or soil or irrigation water could be the source of these microorganisms.