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Made available in DSpace on 2020-12-12T01:17:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-03-02 Delivery efficiencies of theranostic nanoparticles (NPs) based on passive tumor targeting strongly depend either on their blood circulation time or on appropriate modulations of the tumor microenvironment. Therefore, predicting the NP delivery efficiency before and after a tumor microenvironment modulation is highly desirable. Here, we present a new erythrocyte membrane-camouflaged magnetofluorescent nanocarrier (MMFn) with long blood circulation time (92 h) and high delivery efficiency (10% ID for Ehrlich murine tumor model). MMFns owe their magnetic and fluorescent properties to the incorporation of manganese ferrite nanoparticles (MnFe2O4 NPs) and IR-780 (a lipophilic indocyanine fluorescent dye), respectively, to their erythrocyte membrane-derived camouflage. MMFn composition, morphology, and size, as well as optical absorption, zeta potential, and fluorescent, magnetic, and magnetothermal properties, are thoroughly examined in vitro. We then present an analytical pharmacokinetic (PK) model capable of predicting the delivery efficiency (DE) and the time of peak tumor uptake (tmax), as well as changes in DE and tmax due to modulations of the tumor microenvironment, for potentially any nanocarrier. Experimental PK data sets (blood and tumor amounts of MMFns) are simultaneously fit to the model equations using the PK modeling software Monolix. We then validate our model analytical solutions with the numerical solutions provided by Monolix. We also demonstrate how our a priori nonmechanistic model for passive targeting relates to a previously reported mechanistic model for active targeting. All in vivo PK studies, as well as in vivo and ex vivo biodistribution studies, were conducted using two noninvasive techniques, namely, fluorescence molecular tomography (FMT) and alternating current biosusceptometry (ACB). Finally, histopathology corroborates our PK and biodistribution results. Physics Institute Federal University of Goiás Biomagnetism Lab Physics and Biophysics Department São Paulo State University Laboratory of Pharmaceutical Nanotechnology and Drug Delivery Systems School of Pharmacy Federal University of Goiás Biological Sciences Institute Federal University of Goiás Biomagnetism Lab Physics and Biophysics Department São Paulo State University

IR-780 iodide is a fluorescent dye with optical properties in the near-infrared region that has applications in tumor detection and photothermal/photodynamic therapy. This multifunctional effect led to the development of theranostic nanoparticles with both IR-780 and chemotherapeutic drugs such as docetaxel, doxorubicin, and lonidamine. In this work, we developed two albumin-based nanoparticles containing near-infrared IR-780 iodide multifunctional dyes, one of them possessing a magnetic core. Molecular docking with AutoDock Vina studies showed that IR-780 binds to bovine serum albumin (BSA) with greater stability at a higher temperature, allowing the protein binding pocket to better fit this dye. The theoretical analysis corroborates the experimental protocols, where an enhancement of IR-780 was found coupled to BSA at 60 °C, even 30 days after preparation, in comparison to 30 °C. In vitro assays monitoring the viability of Ehrlich ascites carcinoma cells revealed the importance of the inorganic magnetic core on the nanocarrier photothermal-cytotoxic effect. Fluorescence molecular tomography measurements of Ehrlich tumor-bearing Swiss mice revealed the biodistribution of the nanocarriers, with marked accumulation in the tumor tissue (≈3% ID). The histopathological analysis demonstrated strong increase in tumoral necrosis areas after 24 and 72 h after treatment, indicating tumor regression. Tumor regression analysis of nonirradiated animals indicate a IR-780 dose-dependent antitumoral effect with survival rates higher than 70% (animals monitored up to 600 days). Furthermore, an in vivo photothermal therapy procedure was performed and tumor regression was also verified. These results show a novel insight for the biomedical application of IR-780-albumin-based nanocarriers, namely cancer therapy, not only by photoinduced therapy but also by a nonirradiation mechanism. Safety studies (acute oral toxicity, cardiovascular evaluation, and histopathological analysis) suggest potential for clinical translation.

Ruthenium(II)/benzonitrile complexes have demonstrated promising anticancer properties. Considering that there are no specific therapies for treating sarcoma, we decided to evaluate the cytotoxic, genotoxic, and lethal effects of cis-[RuCl(BzCN)(phen)(dppb)]PF6 (BzCN = benzonitrile; phen = 1,10-phenanthroline; dppb = 1,4-bis-(diphenylphosphino)butane), as well as the mechanism of cell death induction that occurs against murine sarcoma-180 tumor. Thus, MTT assay was applied to assess the ruthenium cytotoxicity, showing that the compound is a more potent inhibitor for the sarcoma-180 tumor cell viability than normal cells (lymphocytes). The comet assay indicated low genotoxic for normal cells. cis-[RuCl(BzCN)(phen)(dppb)]PF6 also showed moderate lethality in Artemia salina. The complex induced cell cycle arrest in the G0/G1 phase in sarcoma-180 cells. In addition, the complex caused S180 cells to die by apoptosis by an increase in Annexin-V-positive cells and morphological changes typical of apoptotic cells. Additionally, cis-[RuCl(BzCN)(phen)(dppb)]PF6 increased the gene expression of Bax, Casp3, and Tp53 in S180 cells. By using a western blot, we observed an increased protein level of TNF-R2, Bax, and p21. In conclusion, cis-[RuCl(BzCN)(phen)(dppb)]PF6 is active and selective for sarcoma-180 cells, leading to cell cycle arrest at the G0/G1 and cell death through a caspases-mediated and Tp53/p21-mediated pathway.

Cryptosporidium spp. are an emerging pathogen responsible for a large number of diarrhea outbreaks in humans throughout the world. However, the occurrence of epidemic outbreaks caused by this agent in Brazil is poorly known and still needs more attention mainly in the Central-West Region of Brazil, where yet are not studied. Furthermore, there is a need for cheaper or faster methods for detecting Cryptosporidium spp. (given the cost of Envirocheck® filters and IMS kits). Thus, the implementation of standard techniques that enable the identification and quantification of this agent for further study of environmental samples is important. This study aimed at evaluating and comparing immunological techniques for detection of antigen and a real-time PCR for detection and differentiation of Cryptosporidium spp. in samples of treated water. Samples were collected directly from the taps at the entrance of residences and concentrated by a positively charged membrane filter. Oocysts of Cryptosporidium spp. were detected by direct immunofluorescence, ELISA and real-time PCR techniques, and the results were positive in 56.3 % (18/32), 28.1 % (9/32) and 50.0 % (16/32), respectively. The survey results showed for the first time the presence of Cryptosporidium spp. in treated water in the Central-West Region of Brazil. Although real-time PCR showed less positive, it is the one that enables the identification of the species and less expensive when processing a large number of samples. Probably, it would be better to use both techniques, due to their own virtues.

The goal of this study was to monitor the presence of adenovirus in rivers and lakes used for recreation and as a source for the public water supply in the city of Goiânia, Brazil, in addition to carrying out a correlation analysis of the seasonality of adenovirus gene detection and water quality parameters based on yearly monitoring. We collected 54 water samples from two lakes and two rivers. The samples were concentrated by using a positively-charged membrane, and DNA was extracted by a phenol-chloroform-isoamyl alcohol method, followed by PCR. Adenovirus was detected in 44.4% (24 of 54) of the samples collected. Physicochemical and bacteriological tests were carried out according to water quality monitoring standard procedures. Significant differences over the study period were observed for the presence of adenovirus in water and the values for nitrites, phosphates and fixed and total solids. The occurrence of adenovirus showed a seasonal trend, and significant differences with bacteriological tests were not observed. This is the first study to monitor adenovirus in water sources in the Midwestern Region of Brazil. The results may be useful to generate an eco-epidemiological profile of adenoviruses or even to identify the transmission routes of some neglected diseases, showing the importance in monitoring adenoviruses.

The goal of this study was to standardise and use parasitological and molecular techniques in the analysis and seasonal monitoring of opportunistic protozoa in water from fluvial systems for human usage in the municipality of Goiânia, the capital of the state of Goias, in the mid- western region of Brazil. We focused on Cryptosporidium sp. Cyclospora cayetanensis, Isopora belli, Microsporidia and Giardia lamblia. Water samples were collected monthly from February 2006 to January 2007 and concentrated using vacuum filtration and a positively charged membrane. Sev- eral methods were used to identify the different protozoa of interest. To detect coccidia (Cryptosporidium sp., Isospora belli, and Cyclospora cayetanensis), we used a Kinyoun hot- staining method and a modified Ziehl-Neelsen technique. Enteral microsporidia were detected by a hot-chromotrope technique while a MERIFLUOR ® Cryptosporidium kit was used to confirm the presence of Cryptosporidium sp. Finally, we used PCR to detect Cryptosporidium parvum/hominis. Water is of vital importance to living beings; however, due to anthropic action, several microorganisms are disseminated into aquatic environments. Among them are opportunistic protozoa that infect mainly immunodepressed and immuno- suppressed individuals, children and elderly people. These protozoa pose a significant health hazard. Nevertheless, the presence of these pathogens is underestimated because they are not considered during routine environmental monitor- ing. In our study, we were able to observe the presence of Giardia cysts, Cryptosporidium sp. and Cryptosporidium parvum oocysts in the bodies of water monitored in this re- search.

Adenoviruses are a highly important public health issue, since they are among the most persistent and ubiquitous viruses present in water and associated with a variety of clinical manifestations. The aim of this study was to use molecular techniques for the detection of adenovirus in public and recreational water supplies in Goiânia, Brazil. From December 2007 to November 2008, 54 water samples were collected in 5 different sites in 2 lakes and 2 rivers of the city. The samples were filtered in a positively charged nylon membrane, and the DNA was extracted using the phenol–chloroform–isoamyl alcohol method. Semi-nested PCR was used to detect adenovirus DNA, and sequence analysis of the semi-nested PCR products was performed to identify the recovered viruses. Adenovirus DNA was detected in 43% (24 of 54) of samples collected. Considering all examined sites, MP1 presented the highest occurrence of adenovirus (6 positive from 10 collected samples), followed by MP2 (3 positive from 6 collected samples), JL (10 positive from 21 collected samples), VB (3 positive from 9 collected samples), and BB (2 positive from 8 collected samples), respectively. The methodology employed proved to be feasible, fast, low-cost, and suitable to be used as screening approach on adenovirus detection in water for public sanitation companies.

The objective of this systematic literature review was to identify the occurrence of opportunistic enteric parasites in chronic kidney patient undergoing hemodialysis. The review consisted on searching articles published on MEDLINE, LILACS, SciELO, and PubMed databases between 1991 and 2013. A total 178 articles were identified, ten of which were considered relevant for the present study. In the referred studies, the researchers demonstrated that immunosuppressed patients undergoing hemodialysis are potentially infected by opportunistic enteric agents. Further studies are needed on this topic, as there is a growing global concern with chronic kidney diseases and the potential for these patients contracting opportunistic diseases, which, inclusively, could contaminate hospital environments with opportunistic enteric protozoa. Descriptors: Renal Dialysis; Blastocystis hominis; Cryptosporidium; Cyclospora; Isospora.

The objective of the present work was to register the first proven cases of human pseudomyiasis due to Eristalis tenax in Goiás State, Brazil, underscoring their clinical manifestations and direct relationship with hygiene. The taxonomic identification of the instars was done according to the descriptions and keys presented by James (1947), Hartley (1961) and Guimarães & Papavero (1999). Two cases were observed. In both cases there was no evidence of apparent mental disturbance. The clinical picture of these cases was self limited. The water supply, sewer system, socioeconomic level and habits of the suspect species of the flies are criteria that should be investigated.

Water is a natural resource of vital importance to living beings, but due to anthropic action several microorganisms are disseminated into aquatic environments. In developing countries, over one billion people do not have access to clean, properly treated water and approximately three billion people do not have access to adequate sanitary facilities (Kraszewski et al., 2001) This scenery is probably a consequence of the increased environmental degradation, depletion of water resources, and constant contamination of bodies of water with wastewater and industrial effluents (Pedro & Germano, 2001), causing microorganisms from soil, faeces, decomposing organic matter, and other pollutant sources to spread into water. Goiania, the capital of the state of Goias, located in the Midwestern Region of Brazil, has ca. 1.221.654 inhabitants and is considered a regional metropolis, among the major Brazilian cities that receive a large number of migrants (Alves & Chaveiro 2007). As a result, the city faces problems of disorderly and unsustainable urban growth with a consequent increase in superficial waste, which is a continuous source of contamination of water courses. The current sources of public water supply for the city of Goiania, the Meia Ponte river basin and its tributary river Joao Leite, are constantly submitted to degradation processes due to anthropic action, such as agriculture, intensive livestock production, and urbanization. And although all the water supplies of Goiânia come from this basin (52% from the Joa o Leite River and 48% from the Meia Ponte River), this municipality is its largest polluter (Silva et al., 2010). Among the microorganisms that contaminate the aquatic environment, special attention should be given to opportunistic protozoa, such as Coccidea (Cryptosporidium parvum, Isospora belli, Sarcocystis sp., and Cyclospora sp.) and Microsporidia that infect the