Nanotechnology is a science that involves imaging, measurement, modeling and a manipulation of matter at the nanometric scale. One application of this technology is drug delivery systems based on nanoparticles obtained from natural or synthetic sources. An example of these systems is synthetized from poly(3-hydroxybutyrate-co-3-hydroxyvalerate), which is a biodegradable, biocompatible and a low production cost polymer. The aim of this work was to investigate the uptake mechanism of PHBV nanoparticles in two different epithelial cell lines (HeLa and SKOV-3). As a first step, we characterized size, shape and surface charge of nanoparticles using dynamic light scattering and transmission electron microscopy. Intracellular incorporation was evaluated through flow cytometry and fluorescence microscopy using intracellular markers. We concluded that cellular uptake mechanism is carried out in a time, concentration and energy dependent way. Our results showed that nanoparticle uptake displays a cell-specific pattern, since we have observed different colocalization in two different cell lines. In HeLa (Cervical cancer cells) this process may occur via classical endocytosis pathway and some internalization via caveolin-dependent was also observed, whereas in SKOV-3 (Ovarian cancer cells) these patterns were not observed. Rearrangement of actin filaments showed differential nanoparticle internalization patterns for HeLa and SKOV-3. Additionally, final fate of nanoparticles was also determined, showing that in both cell lines, nanoparticles ended up in lysosomes but at different times, where they are finally degraded, thereby releasing their contents. Our results, provide novel insight about PHBV nanoparticles internalization suggesting that for develop a proper drug delivery system is critical understand the uptake mechanism.

Gene expression profiling of normal receptive endometrium has been characterized, but intrinsic defects in endometrial gene expression associated with implantation failure have not been reported. Women who had previously participated as recipients in oocyte donation cycles and repeatedly exhibited implantation failure (Group A, study group) or had at least one successful cycle (Group B, control group) and spontaneously fertile women (Group C, normal fertility group) were recruited. All were treated with exogenous estradiol and progesterone to induce an endometrial cycle, and an endometrial biopsy was taken on the seventh day of progesterone administration. RNA from each sample was analysed by cDNA microarrays to identify differentially expressed genes between groups. 63 transcripts were differentially expressed (≥2-fold) between Groups A and B, of which 16 were subjected to real time RT–PCR. Eleven of these were significantly decreased in Group A with regard to Groups B and C. Among the dysregulated genes were MMP-7, CXCR4, PAEP and C4BPA. Repeated implantation failure in some oocyte recipients is associated with an intrinsic defect in the expression of multiple genes in their endometrium. Significantly decreased levels of several transcripts in endometria without manifest abnormalities is demonstrated for the first time and shown to be associated with implantation failure.

Infection of the Fallopian tubes (FT) byNeisseria gonorrhoeaecan lead to acute salpingitis, an inflammatory condition, which is a major cause of infertility. Challenge of explants of human FT with gonococci induced mRNA expression and protein secretion for the proinflammatory cytokines interleukin (IL)-1α, IL-1β, and tumor necrosis factor alpha (TNF-α) but not for granulocyte-macrophage colony-stimulating factor. In contrast, FT expression of IL-6 and of the cytokine receptors IL-6R, TNF receptor I (TNF-RI), and TNF-RII was constitutive and was not increased by gonococcal challenge. These studies suggest that several proinflammatory cytokines are likely to contribute to the cell and tissue damage observed in gonococcal salpingitis.

Following infection withNeisseria gonorrhoeae, bacteria may ascend into the Fallopian tubes (FT) and induce salpingitis, a major cause of infertility. In the FT, interactions between mucosal epithelial cells and gonococci are pivotal events in the pathogen's infection cycle and the inflammatory response. In the current study, primary FT epithelial cells were infected in vitro with different multiplicities of infection (MOI) of Pil⁺Opa⁺gonococci. Bacteria showed a dose-dependent association with cells and induced the secretion of tumor necrosis factor alpha (TNF-α). A significant finding was that gonococcal infection (MOI = 1) induced apoptosis in approximately 30% of cells, whereas increasing numbers of bacteria (MOI = 10 to 100) did not induce apoptosis. Apoptosis was observed in only 11% of cells with associated bacteria, whereas >84% of cells with no adherent bacteria were apoptotic. TNF-α was a key contributor to apoptosis, since (i) culture supernatants from cells infected with gonococci (MOI = 1) induced apoptosis in naïve cultures, suggesting that a soluble factor was responsible; (ii) gonococcal infection-induced apoptosis was inhibited with anti-TNF-α antibodies; and (iii) the addition of exogenous TNF-α induced apoptosis, which was inhibited by the presence of increasing numbers of bacteria (MOI = 10 to 100). These data suggest that TNF-α-mediated apoptosis of FT epithelial cells is likely a primary host defense mechanism to prevent pathogen colonization. However, epithelial cell-associated gonococci have evolved a mechanism to protect the cells from undergoing TNF-α-mediated apoptosis, and this modulation of the host innate response may contribute to establishment of infection. Understanding the antiapoptotic mechanisms used byNeisseria gonorrhoeaewill inform the pathogenesis of salpingitis and could suggest new intervention strategies for prevention and treatment of the disease.