Publications by authors named "Achim M Loske"

In this study, green chemistry was used as a tool to obtain gold nanoparticles using extracts as a synthesis medium. Green ethanolic and aqueous extracts were obtained using ultrasound and shock wave-assisted extraction. Gold nanoparticles with sizes ranging between 100 and 150 nm were obtained with ultrasound aqueous extract.

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This work describes the genetic transformation of a strain of Aspergillus niger with five different constructs containing 16 different heterologous genes, coding for four oxidoreductases, two cellobiohydrolases, one endoglucanase, one β-glucosidase, six enzymes involved in xylose metabolism, and two enzymes involved in fermentation. The aim was to try and engineer a consolidated bioprocessing in A. niger.

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Shock waves, as used in medicine, can induce cell permeabilization, genetically transforming filamentous fungi; however, little is known on the interaction of shock waves with the cell wall. Because of this, the selection of parameters has been empirical. We studied the influence of shock waves on the germination of , to understand their effect on the modulation of four genes related to the growth of conidia.

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Aspergillus niger has been employed to produce heterologous proteins due to its high capacity for expression and secretion; nevertheless, expression levels of human proteins have been modest. We were interested in investigating whether A. niger can express and secret human erythropoietin (HuEPO) at high yields.

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We evaluated the effect of oral molecular iodine supplementation and shock wave application under three different conditions on human MDA-MB231 cancer cell xenografts. After tumor volume reached 1 cm, mice were randomly assigned to groups and treated for 3 weeks. The results revealed that high-dose shock wave treatment (150 shock waves at a pressure of 21.

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Phenolic compounds, obtained from plants are important in the food, biomaterial and pharmaceutical industries; however current extraction methods, such as Soxhlet (solid-liquid) extraction, liquid-liquid extraction, microwave-assisted extraction, and ultrasonic extraction (USE), have the disadvantages of large processing times, contamination by solvents, and degradation of analytes. This study demonstrates that shock wave-assisted extraction can be used as a more efficient, eco-friendly and rapid method. Extraction of powdered samples of Eysenhardtia polystachia heartwood, a plant with high concentration of phenolic compounds, exposed to different doses of underwater shock waves, was compared with the conventional methods.

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The purpose of this work was to develop a metamodel (Kriging model) to identify the most important input parameters of shock wave pressure profiles as used in biomedical applications without solving a large number of differential equations. Shock wave-induced cavitation is involved in several biological effects. During bubble collapse, secondary shock waves and microjets are formed.

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Controlled permeabilization of mammalian cell membranes is fundamental to develop gene and cell therapies based on macromolecular cargo delivery, a process that emerged against an increasing number of health afflictions, including genetic disorders, cancer and infections. Viral vectors have been successfully used for macromolecular delivery; however, they may have unpredictable side effects and have been limited to life-threatening cases. Thus, several chemical and physical methods have been explored to introduce drugs, vaccines, and nucleic acids into cells.

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Ligninolytic enzyme production and lignin degradation are typically the rate-limiting steps in the biofuel industry. To improve the efficiency of simultaneous bio-delignification and enzyme production, Phanerochaete chrysosporium was transformed by shock wave-induced acoustic cavitation to co-overexpress 3 peroxidases and 1 laccase and test it on the degradation of sugarcane bagasse and wheat bran. Lignin depolymerization was enhanced by up to 25% in the presence of recombinant fungi in comparison with the wild-type strain.

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Multidrug-resistant microorganisms are of great concern to public health. Genetic mobile elements, such as plasmids, are among the most relevant mechanisms by which bacteria achieve this resistance. We obtained an Escherichia coli strain CM6, isolated from cattle presenting severe diarrheic symptoms in the State of Querétaro, Mexico.

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Nucleoside hydrolase and sterol 24-c-methyltransferase, two antigenic proteins of Leishmania sp., were expressed in Aspergillus niger. Genetic transformation of conidia was achieved using underwater shock waves.

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A comparison between plate counting (PC) and dynamic light scattering (DLS) is reported. PC is the standard technique to determine bacterial population as a function of time; however, this method has drawbacks, such as the cumbersome preparation and handling of samples, as well as the long time required to obtain results. Alternative methods based on optical density are faster, but do not distinguish viable from non-viable cells.

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Shock waves are known to permeabilize eukaryotic cell membranes, which may be a powerful tool for a variety of drug delivery applications. However, the mechanisms involved in shock wave-mediated membrane permeabilization are still poorly understood. In this study, the effects on both the permeability and the ultrastructural features of two human cell lineages were investigated after the application of underwater shock waves in vitro.

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Black leaf streak disease, also known as black Sigatoka, causes dramatic losses in production of banana and plantains fruits. The disease is caused by the pathogenic fungus Mycosphaerella fijiensis (anamorph Pseudocercospora fijiensis; Mycosphaerellaceae). Genetic transformation of M.

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Phanerochaete chrysosporium belongs to a group of lignin-degrading fungi that secretes various oxidoreductive enzymes, including lignin peroxidase (LiP) and manganese peroxidase (MnP). Previously, we demonstrated that the heterologous expression of a versatile peroxidase (VP) in P. chrysosporium recombinant strains is possible.

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Extracorporeal shock wave lithotripsy is a common non-invasive treatment for urinary stones whose fragmentation is achieved mainly by acoustic cavitation and mechanical stress. A few years ago, in vitro and in vivo experimentation demonstrated that such fragmentation can be improved, without increasing tissue damage, by sending a second shock wave hundreds of microseconds after the previous wave. Later, numerical simulations revealed that if the second pulse had a longer full width at half maximum than a standard shock wave, cavitation could be enhanced significantly.

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The white-rot fungus Phanerochaete chrysosporium secretes extracellular oxidative enzymes during secondary metabolism, but lacks versatile peroxidase, an enzyme important in ligninolysis and diverse biotechnology processes. In this study, we report the genetic modification of a P. chrysosporium strain capable of co-expressing two endogenous genes constitutively, manganese peroxidase (mnp1) and lignin peroxidase (lipH8), and the codon-optimized vpl2 gene from Pleurotus eryngii.

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To determine the concentration of bacteria in a sample is important in the food industry, medicine and biotechnology. A disadvantage of the plate-counting method is that a microorganism colony could arise from one cell or from many cells. The other standard methodology, known as optical density determination, is based on the turbidity of a suspension and registers all bacteria, dead and alive.

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Filamentous fungi are used in several industries and in academia to produce antibiotics, metabolites, proteins and pharmaceutical compounds. The development of valuable strains usually requires the insertion of recombinant deoxyribonucleic acid; however, the protocols to transfer DNA to fungal cells are highly inefficient. Recently, underwater shock waves were successfully used to genetically transform filamentous fungi.

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Cationic lipid/DNA complexes (lipoplexes) represent a powerful tool for cell transfection; however, their use is still limited by important concerns, including toxicity and poor internalization into deep tissues. In this work, we investigated the use of shock wave-induced acoustic cavitation in vitro for the transfection of lipoplexes in human embryo kidney 293 cells. We selected shock waves with the ability to internalize 10-kDa fluorescein isothiocyanate-dextran into cells while maintaining survival rates above 50%.

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The production of transgenic fungi is a routine process. Currently, it is possible to insert genes from other fungi, viruses, bacteria and even animals, albeit with low efficiency, into the genomes of a number of fungal species. Genetic transformation requires the penetration of the transgene through the fungal cell wall, a process that can be facilitated by biological or physical methods.

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Genetic transformation of filamentous fungi is an essential tool in many areas such as biotechnology, medicine, phytopathology and genetics. However, available protocols to transform fungi are inefficient, laborious and have low reproducibility. We report the use of underwater shock waves as a novel method to transform filamentous fungi.

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