La adición de Enterococcus faecium aumenta la respuesta inmune intestinal en cerdos en crecimiento

El destete produce un periodo breve de ayuno y adaptación a una nueva ración sólida, la cual provoca disminución de la supervivencia de los lechones y proliferación de la microbiota patógena. Se ha propuesto la utilización de probióticos, evitando que los seres humanos consuman alimentados tratados con antibióticos. El objetivo de este trabajo fue determinar el efecto de la adición de cepas de probióticos en cerdos en crecimiento sobre las poblaciones celulares del sistema inmune (eosinófilos, basófilos, neutrófilos, monocitos y linfocitos) en intestino delgado. Se sacrificaron 35 lechones escalonadamente los días 1 (21 días de edad), 15 y 30 posdetete, y se extrajo completamente el intestino. Los animales fueron alimentados con dos dietas: dieta comercial con y sin la adición de antibiótico; a esta última se adicionaron los diferentes probióticos (Lactobacillus casei, Lactobacillus acidophilus o Enterococcus faecium) en el agua de bebida. Se utilizó un diseño de bloques al azar en un arreglo de parcelas divididas. Los aislamientos realizados a partir de las muestras intestinales de E. faecium presentaron un mayor número de poblaciones celulares del sistema inmune a nivel intestinal (p<0.01). Además, se realizó medición del pH intestinal, el cual presentó una disminución estadística significativa (p<0.01), donde los animales que consumieron E. faecium presentaron los valores más bajos de pH intestinal, frente a aquellos que consumieron la dieta con adición de antibiótico. La adición de la cepa E. faecium en el alimento de lechones recién destetados, estimula el aumento en el número de poblaciones celulares intestinales del sistema inmune y alcanzan una mayor disminución del pH intestinal.

Crecimiento y desarrollo intestinal de aves de engorde alimentadas con cepas probióticas

A través de la alimentación, los animales se exponen a agentes extraños, donde el epitelio intestinal actúa como una barrera natural contra las bacterias y sustancias tóxicas que estén presentes en el lumen intestinal. No obstante, la ingesta de bacterias probióticas podría influir sobre el desarrollo y función de órganos digestivos, específicamente el intestino, mejorando los parámetros fisiológicos, nutricionales e inmunológicos de este. El objetivo de este trabajo fue evaluar diferentes cepas probióticas sobre el crecimiento alométrico y desarrollo intestinal de pollos de engorde durante su etapa productiva. Se utilizaron 125 pollos machos (Cobb) de un día de edad y alimentados con dos dietas: dieta comercial con y sin la adición de antibiótico. Los diferentes probióticos (Lactobacillus casei, Lactobacillus acidophilus ó Enterococcus faecium) se suministraron en el agua de bebida de los animales que consumieron la dieta basal sin antibiótico garantizando una concentración de 107 UFC/ml. El diseño estadístico utilizado fue de bloques al azar en arreglo de parcelas divididas. La inclusión de probióticos, específicamente E. faecium, en la alimentación de pollos de engorde mejoraron el peso, desarrollo y crecimiento de órganos de importancia digestiva, específicamente intestino, lo cual se ve reflejado en vellosidades con mayor altura y ancho, y criptas menos profundas (p

Mitochondrially Targeted Nanoparticles Based on α-TOS for the Selective Cancer Treatment

The aim of this work is the preparation of an active nanovehicle for the effective administration of α-tocopheryl succinate (α-TOS). α-TOS is loaded in the core of nanoparticles (NPs) based on amphiphilic pseudo-block copolymers of N-vinyl pyrrolidone and a methacrylic derivative of α-TOS. These well-defined spherical NPs have sizes below 165 nm and high encapsulation efficiencies. In vitro activity of NPs is tested in hypopharynx squamous carcinoma (FaDu) cells and nonmalignant epithelial cells, demonstrating that the presence of additional α-TOS significantly enhances its antiproliferative activity; however, a range of selective concentrations is observed. These NPs induce apoptosis of FaDu cells by activating the mitochondria death pathway (via caspase-9). Both loaded and unloaded NPs act via complex II and produce high levels of reactive oxygen species that trigger apoptosis. Additionally, these NPs effectively suppress the vascular endothelial growth factor (VEGF) expression of human umbilical vein endothelial cells (HUVECs). These results open the possibility to use this promising nanoformulation as an α-TOS delivery system for the effective cancer treatment, effectively resolving the current limitations of free α-TOS administration.

[Functional outcomes obtained after vesicoureteral reimplantation surgery in adults: A review]

OBJECTIVES

Vesico-ureteral reimplantations (VUR) for adults are complex procedures, often practicing for distal ureteral lesions. Our goal was to synthesis the main indications for VUR, different techniques and their functional outcomes.

MATERIAL AND METHODS

A literature review in English by Medline, Embase and Google scholar was performed using the following keywords: ureter; laparoscopy; robotics, reimplantation; surgery; obstruction; morbidity; complications; psoas hitch; Boari flap; ureteroneocystostomy.

RESULTS

In more than half of the cases, aetiology was a iatrogenic ureteral lesion. When the ureteral defect was less than 2 cm, direct or non-refluxing VUR was the technique of choice. If defect was superior than 2 cm the Boari flap or vesicopsoas hitch were preferred. Several surgical approaches were feasible: open, laparoscopic only, robot assisted laparoscopic. Estimated blood loss, pain and mean hospital stay seemed better with conventional or robotic coelioscopy. Nevertheless, complications, pre-/post-operative renal function and mean operative time seemed similar. The most frequent major complication was the anastomotic urine leakage.

CONCLUSIONS

The VUR techniques are well codified now even if it's a rare procedure. Functional outcomes are satisfied according to literature and morbidity is more and more decreasing but the level of evidence of the studies is low.

Anticancer and antiangiogenic activity of surfactant-free nanoparticles based on self-assembled polymeric derivatives of vitamin E: structure-activity relationship

α-Tocopheryl succinate (α-TOS) is a well-known mitochondrially targeted anticancer compound, however, it is highly hydrophobic and toxic. In order to improve its activity and reduce its toxicity, new surfactant-free biologically active nanoparticles (NP) were synthesized. A methacrylic derivative of α-TOS (MTOS) was prepared and incorporated in amphiphilic pseudoblock copolymers when copolymerized with N-vinylpyrrolidone (VP) by free radical polymerization (poly(VP-co-MTOS)). The selected poly(VP-co-MTOS) copolymers formed surfactant-free NP by nanoprecipitation with sizes between 96 and 220 nm and narrow size distribution, and the in vitro biological activity was tested. In order to understand the structure-activity relationship three other methacrylic monomers were synthesized and characterized: MVE did not have the succinate group, SPHY did not have the chromanol ring, and MPHY did not have both the succinate group and the chromanol ring. The corresponding families of copolymers (poly(VP-co-MVE), poly(VP-co-SPHY), and poly(VP-co-MPHY)) were synthesized and characterized, and their biological activity was compared to poly(VP-co-MTOS). Both poly(VP-co-MTOS) and poly(VP-co-MVE) presented triple action: reduced cell viability of cancer cells with little or no harm to normal cells (anticancer), reduced viability of proliferating endothelial cells with little or no harm to quiescent endothelial cells (antiangiogenic), and efficiently encapsulated hydrophobic molecules (nanocarrier). The anticancer and antiangiogenic activity of the synthesized copolymers is demonstrated as the active compound (vitamin E or α-tocopheryl succinate) do not need to be cleaved to trigger the biological action targeting ubiquinone binding sites of complex II. Poly(VP-co-SPHY) and poly(VP-co-MPHY) also formed surfactant-free NP that were also endocyted by the assayed cells; however, these NP did not selectively reduce cell viability of cancer cells. Therefore, the chromanol ring of the vitamin E analogues has an important role in the biological activity of the copolymers. Moreover, when succinate moiety is substituted and vitamin E is directly linked to the macromolecular chain through an ester bond, the biological activity is maintained.

Synthesis and characterization of self-curing hydrophilic bone cements for protein delivery

New formulations of acrylic bone cements for bone defect reparation, based on self-hardening methyl methacrylate (MMA)/methacrylic acid (MAA), with a high capacity for protein delivery, have been developed. The self-curing formulations were prepared by partial substitution of solid phase PMMA microparticles by newly obtained PMAA microspheres. The PMAA microspheres were prepared by inverse suspension polymerization of their monomer and were cross-linked with N,N'-methylene-bis-acrylamide (MBA) (10-15 wt %) to produce stable systems in contact with aqueous media. PMAA microspheres were loaded with hydrolyzed collagen (HC) as a model protein to simulate bone morphogenetic protein delivery useful for hard tissue reconstruction. Solid phase PMMA microparticles in the formulation were partially substituted by new PMAA-HC microspheres and were characterized to determine viability as an acrylic bone cement in minimally invasive surgery. The incorporation of PMAA-HC microspheres decreased peak temperature by 20°C, which minimized thermal necrotic risk after implantation. Mechanical compression tests revealed a behavior, under dry conditions, close to ISO 5833 standard requirements. However, a drastic drop in mechanical strength, ∼64%, was obtained after 15 days of immersion in simulated physiological conditions (37°C and pH 7.4) and was attributed to water absorption and a subsequent plasticizing effect. The increase in water uptake and retention enhanced the capability for controlled protein delivery. Finally, the biocompatibility of the cements was determined; some toxicity of the material during the first hours of culture incubation was observed. Later, toxicity was observed to decrease due to nonreacted monomer leaching, which ensured the low toxicity of the already polymerized phase.

β-Dicalcium silicate-based cement: synthesis, characterization and in vitro bioactivity and biocompatibility studies

β-dicalcium silicate (β-Ca₂ SiO₄, β-C₂ S) is one of the main constituents in Portland cement clinker and many refractory materials, itself is a hydraulic cement that reacts with water or aqueous solution at room/body temperature to form a hydrated phase (C-S-H), which provides mechanical strength to the end product. In the present investigation, β-C₂ S was synthesized by sol-gel process and it was used as powder to cement preparation, named CSiC. In vitro bioactivity and biocompatibility studies were assessed by soaking the cement samples in simulated body fluid solutions and human osteoblast cell cultures for various time periods, respectively. The results showed that the sol-gel process is an available synthesis method in order to obtain a pure powder of β-C₂ S at relatively low temperatures without chemical stabilizers. A bone-like apatite layer covered the material surface after soaking in SBF and its compressive strength (CSiC cement) was comparable with that of the human trabecular bone. The extracts of this cement were not cytotoxic and the cell growth and relative cell viability were comparable to negative control.

[Prognostic influence of prostate gland invasion by bladder tumour and/or prostate cancer in cystoprostatectomy specimen: a review]

INTRODUCTION

Cystoprostatectomy (CPT) is the gold standard surgical treatment for muscle invasive bladder cancer (MIBC). In certain cases, MIBC can invade the prostate gland and/or a prostate cancer (PCa) can be discovered fortuitously on the pathologic specimen. The aim of the current study was to report the prognostic influence of PCa in patients who underwent a CPT for MIBC.

MATERIALS AND METHODS

A systematic review of the scientific literature was achieved in the Pubmed database, using the following keywords: prostatic neoplasm; urinary bladder neoplasm; cystectomy; surgery; recurrence; prognosis; survival. Clinical cases and series of less than five cases were deliberately excluded herein.

RESULTS

Overall, ten studies published between 2004 and 2011 and involving 2196 patients were selected. Only retrospective studies of low level of evidence (NP 4) were available. The incidence of neoplastic invasion of the prostate gland by MIBC ranged from 25 to 48%. Preoperative predictors were multiple BC, recurrent, location in the trigone and existence of CIS. Overall survival at 3 years was significantly affected by the invasion of the prostate gland (pT4a) in these patients. The incidence of PCa discovered incidentally pathologic specimen CPT ranged from 14 to 49%. Only age was found as a positive predictor. The diagnosis of PCa did not influence survival of patients with MIBC and no specific PCa adjuvant treatment was systematically advocated.

CONCLUSION

Fortuitous diagnosis of PCa and/or neoplastic invasion of the prostatic gland by BC on CPT specimen is not uncommon but this is variable across studies, depending on the quality of the pathological analysis. The invasion of the prostate gland by MIBC is a serious situation (pT4a) and linked with a poor prognosis. In case of concomitant PCa and MIBC, the prognosis is much more related to the natural history of the bladder tumour.

Bioactive coatings for coronary stents: Modulation of cell proliferation by controlled release of anti-proliferative drugs

Drug eluting coronary stents coated with a bioactive and biostable polymer system (THBA70), based on acrylate copolymers bearing a salicylic acid derivative as side substituent, were evaluated. The microstructural architecture of the copolymer THBA70 comprises a random copolymer of a methacrylate derivative from triflusal (4-trifluoromethyl salicylic acid) with 45 mol% of THEMA (2-methacryloyloxyethyl [2-(acetyloxy)-4-(trifluoromethyl)] benzoate), which makes the system anti-thrombogenic with good adhesion to the surface of metallic stents. The bioactive coating prevented thrombosis, an adverse effect associated with the implantation of drug-eluting stents. The in vitro drug delivery of drug-eluting stents under dynamic conditions indicated excellent controlled drug release. The THBA70 films loaded with relatively low concentrations of taxol or simvastatin in contact with fibroblasts produced inhibition of cell proliferation with a dose-dependent bioactivity.