In Vivo Efficacy and Toxicity of Curcumin Nanoparticles in Breast Cancer Treatment: A Systematic Review.

Breast cancer is one of the most prevalent types of malignant tumors in the world, resulting in a high incidence of death. The development of new molecules and technologies aiming to apply more effective and safer therapy strategies has been intensively explored to overcome this situation. The association of nanoparticles with known antitumor compounds (including plant-derived molecules such as curcumin) has been considered an effective approach to enhance tumor growth suppression and reduce adverse effects. Therefore, the objective of this systematic review was to summarize published data regarding evaluations about efficacy and toxicity of curcumin nanoparticles (Cur-NPs) in in vivo models of breast cancer. The search was carried out in the databases: CINAHL, Cochrane, LILACS, Embase, FSTA, MEDLINE, ProQuest, BSV regional portal, PubMed, ScienceDirect, Scopus, and Web of Science. Studies that evaluated tumor growth in in vivo models of breast cancer and showed outcomes related to Cur-NP treatment (without association with other antitumor molecules) were included. Of the 528 initially gathered studies, 26 met the inclusion criteria. These studies showed that a wide variety of NP platforms have been used to deliver curcumin (e.g., micelles, polymeric, lipid-based, metallic). Attachment of poly(ethylene glycol) chains (PEG) and active targeting moieties were also evaluated. Cur-NPs significantly reduced tumor volume/weight, inhibited cancer cell proliferation, and increased tumor apoptosis and necrosis. Decreases in cancer stem cell population and angiogenesis were also reported. All the studies that evaluated toxicity considered Cur-NP treatment to be safe regarding hematological/biochemical markers, damage to major organs, and/or weight loss. These effects were observed in different in vivo models of breast cancer (e.g., estrogen receptor-positive, triple-negative, chemically induced) showing better outcomes when compared to treatments with free curcumin or negative controls. This systematic review supports the proposal that Cur-NP is an effective and safe therapeutic approach in in vivo models of breast cancer, reinforcing the currently available evidence that it should be further analyzed in clinical trials for breast cancer treatments.

Photobiomodulation and different macrophages phenotypes during muscle tissue repair.

Macrophages play a very important role in the conduction of several regenerative processes mainly due to their plasticity and multiple functions. In the muscle repair process, while M1 macrophages regulate the inflammatory and proliferative phases, M2 (anti-inflammatory) macrophages direct the differentiation and remodelling phases, leading to tissue regeneration. The aim of this study was to evaluate the effect of red and near infrared (NIR) photobiomodulation (PBM) on macrophage phenotypes and correlate these findings with the repair process following acute muscle injury. Wistar rats were divided into 4 groups: control; muscle injury; muscle injury + red PBM; and muscle injury + NIR PBM. After 2, 4 and 7 days, the tibialis anterior muscle was processed for analysis. Macrophages phenotypic profile was evaluated by immunohistochemistry and correlated with the different stages of the skeletal muscle repair by the qualitative and quantitative morphological analysis as well as by the evaluation of IL-6, TNF-α and TGF-ß mRNA expression. Photobiomodulation at both wavelengths was able to decrease the number of CD68+ (M1) macrophages 2 days after muscle injury and increase the number of CD163+ (M2) macrophages 7 days after injury. However, only NIR treatment was able to increase the number of CD206+ M2 macrophages (Day 2) and TGF-ß mRNA expression (Day 2, 4 and 7), favouring the repair process more expressivelly. Treatment with PBM was able to modulate the inflammation phase, optimize the transition from the inflammatory to the regeneration phase (mainly with NIR light) and improve the final step of regeneration, enhancing tissue repair.

Preparation and characterization of collagen-nanohydroxyapatite biocomposite scaffolds by cryogelation method for bone tissue engineering applications.

Recent efforts of bone repair focus on development of porous scaffolds for cell adhesion and proliferation. Collagen-nanohydroxyapatite (HA) scaffolds (70:30; 50:50; and 30:70 mass percentage) were produced by cryogelation technique using 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide hydrochloride/N-hydroxysuccinimide as crosslinking agents. A pure collagen scaffold was used as control. Morphology analysis revealed that all cryogels had highly porous structure with interconnective porosity and the nanoHA aggregates were randomly dispersed throughout the scaffold structure. Chemical analysis showed the presence of all major peaks related to collagen and HA in the biocomposites and indicated possible interaction between nanoHA aggregates and collagen molecules. Porosity analysis revealed an enhancement in the surface area as the nanoHA percentage increased in the collagen structure. The biocomposites showed improved mechanical properties as the nanoHA content increased in the scaffold. As expected, the swelling capacity decreased with the increase of nanoHA content. In vitro studies with osteoblasts cells showed that they were able to attach and spread in all cryogels surfaces. The presence of collagen-nanoHA biocomposites resulted in higher overall cellular proliferation compared to pure collagen scaffold. A statistically significant difference between collagen and collagen-nanoHA cryogels was observed after 21 day of cell culture. These innovative collagen-nanoHA cryogels could have potentially appealing application as scaffolds for bone regeneration.

Evaluation of the binding properties of maghemite nanoparticle surface-coated with meso-2-3-dimercaptosuccinic acid to serum albumin.

In this study the interaction between magnetic nanoparticles (MNPs) surface-coated with meso-2,3-dimercaptosuccinic acid (DMSA) with both bovine serum albumin (BSA) and human serum albumin (HSA) was investigated. The binding of the MNP-DMSA was probed by the fluorescence quenching of the BSA and HSA tryptophan residue. Magnetic resonance and light microscopy analyses were carried out in in vivo tests using female Swiss mice. The binding constants (Kb) and the complex stoichiometries (n) indicate that MNP-DMSA/BSA and MNP-DMSA/HSA complexes have low association profiles. After five minutes following intravenous injection of MNP-DMSA into mice's blood stream we found the lung firstly target by the MNP-DMSA, followed by the liver in a latter stage. This finding suggests that the nanoparticle's DMSA-coating process probably hides the thiol group, through which albumin usually binds. This indicates that biocompatible MNP-DMSA is a very promising material system to be used as a drug delivery system (DDS), primarily for lung cancer treatment.

Emprego de quatro exames imunológicos na determinaçäo da prevalência da doença de Chagas nos garis do Serviço de Limpeza Urbana do Distrito Federal / The use of four immunological tests to determine the prevalence of Chagas' disease in street cleaners of the Urban Cleaning Service of the Federal District

Seropositivity for Trypanosoma cruzi infection was studied in 368 street-sweepers of the SLU, Federal District, Brazil, with the aid of haemaglutination, immunofluorescence and, also, a delayed-type skin test to the parasite T12E antigen. It showed 32.1 per cent, 42.1 per cent and 38.6 per cent positive results, respectively for each assay. Among these, however, only 47 per cent were positive with each of three exams performed. In addition, 19.7 per cent were positive with two out of three exams performed. The remaining 33.3 per cent sera yielded one positive result out of three exams employed and were submitted to the immunoblot assay. This analysis confirmed 3 cases (37.5 per cent) positive by hemmaglutination, 3 (11.5 per cent) positive by skin test, and 1 (3.7 per cent) positive by immunofluorescence. At the end of the analysis, it was shown that 129 (35 per cent) individuals yielded at least two positive assays and, therefore, they should be considered as T. cruzi-infected individuals.