20 research outputs found
Incremento del efecto citotóxico de un fármaco antineoplásico mediante la expresión de la glicoproteína fusogénica del virus SV 5
Tesis (Doctor en Ciencias con Orientación en Farmacia) UANL, 2010.UANLhttp://www.uanl.mx
Generación de electricidad a partir de una CCM de doble cámara utilizando Serratia marcescens como biocatalizador.
Evaluación de metabolitos bioactivos producidos por Cladosporium cladosporioides y análisis de su actividad antiviral contra el virus del herpes simplex tipo 1.
Producción de celulasas de Penicillium sp. empleando el bagazo de las hojas de Agave salmiana.
Evaluación del extracto alcohólico de las hojas de Agave salmiana como agente antimicrobiano y su posible aplicación en una fermentación alcohólica.
Synergistic Antimicrobial Effects of Silver/Transition-metal Combinatorial Treatments
Due to the emergence of multi-drug resistant strains, development of novel antibiotics has become
a critical issue. One promising approach is the use of transition metals, since they exhibit rapid and
significant toxicity, at low concentrations, in prokaryotic cells. Nevertheless, one main drawback of
transition metals is their toxicity in eukaryotic cells. Here, we show that the barriers to use them as
therapeutic agents could be mitigated by combining them with silver. We demonstrate that synergism
of combinatorial treatments (Silver/transition metals, including Zn, Co, Cd, Ni, and Cu) increases up
to 8-fold their antimicrobial effect, when compared to their individual effects, against E. coli and B.
subtilis. We find that most combinatorial treatments exhibit synergistic antimicrobial effects at low/
non-toxic concentrations to human keratinocyte cells, blast and melanoma rat cell lines. Moreover, we
show that silver/(Cu, Ni, and Zn) increase prokaryotic cell permeability at sub-inhibitory concentrations,
demonstrating this to be a possible mechanism of the synergistic behavior. Together, these results
suggest that these combinatorial treatments will play an important role in the future development of
antimicrobial agents and treatments against infections. In specific, the cytotoxicity experiments show
that the combinations have great potential in the treatment of topical infections
Metal-Induced Production of a Novel Bioadsorbent Exopolysaccharide in a Native Rhodotorula mucilaginosa from the Mexican Northeastern Region
There is a current need to develop low-cost strategies to degrade and eliminate industrially
used colorants discharged into the environment. Colorants discharged into natural water
streams pose various threats, including: toxicity, degradation of aesthetics and inhibiting
sunlight penetration into aquatic ecosystems. Dyes and colorants usually have complex aromatic
molecular structures, which make them very stable and difficult to degrade and eliminate
by conventional water treatment systems. The results in this work demonstrated that
heavy metal-resistant Rhodotorula mucilaginosa strain UANL-001L isolated from the northeast
region of Mexico produce an exopolysaccharide (EPS), during growth, which has colorant
adsorption potential. The EPS produced was purified by precipitation and dialysis and
was then physically and chemically characterized by Scanning Electron Microscopy, Fourier
Transform Infrared Spectroscopy, and chemical elemental analysis. Here, the ability of the
purified EPS produced to adsorb methylene blue (MB), which served as a model colorant, is
studied. MB adsorption by the EPS is found to follow Langmuir Adsorption Isotherm kinetics
at 25°C. Further, by calculating the Langmuir constant the adsorption capabilities of the EPS
produced by the Rhodotorula mucilaginosa strain UANL-001L is compared to that of other
adsorbents, both, microbially produced and from agroindustrial waste. The total adsorption
capacity of the EPS, from the Rhodotorula mucilaginosa strain UANL-001L, was found to be
two-fold greater than the best bioadsorbents reported in the literature. Finally, apart from
determining which heavy metals stimulated EPS production in the strain, the optimal conditions
of pH, heavy metal concentration, and rate of agitation of the growing culture for EPS production, was determined. The EPS reported here has the potential of aiding in the efficient
removal of colorants both in water treatment plants and in situ in natural water streams