Insights into the biosynthesis of palladium nanoparticles for oxygen reduction reaction by genetically engineered bacteria of Shewanella oneidensis MR-1.

Owing to the increasing need for green synthesis and environmental protection, the utilization of biological organism-derived carbons as supports for noble-metal electrocatalysts has garnered public interest. Nevertheless, the mechanism by which microorganisms generate nanometals has not been fully understood yet. In the present study, we used genetically engineered bacteria of Shewanella oneidensis MR-1 (∆SO4317, ∆SO4320, ∆SO0618 and ∆SO3745) to explore the effect of surface substances including biofilm-associated protein (bpfA), protein secreted by type I secretion systems (TISS) and type II secretion systems (T2SS), and lipopolysaccharide in microbial synthesis of metal nanoparticles. Results showed Pd/∆SO4317 (the catalyst prepared with the mutant ∆SO4317) shows better performance than other biocatalysts and commercial Pd/C, where the mass activity (MA) and specific activity (SA) of Pd/∆SO4317 are 3.1 and 2.1 times higher than those of commercial Pd/C, reaching 257.49 A g-1 and 6.85 A m-2 respectively. It has been found that the exceptional performance is attributed to the smallest particle size and the presence of abundant functional groups. Additionally, the absence of biofilms has been identified as a crucial factor in the formation of high-quality bio-Pd. Because the absence of biofilm can minimize metal agglomeration, resulting in uniform particle size dispersion. These findings provide valuable mechanical insights into the generation of biogenic metal nanoparticles and show potential industrial and environmental applications, especially in accelerating oxygen reduction reactions.

Engineered Microorganisms for Advancing Tumor Therapy.

Engineered microorganisms have attracted significant interest as a unique therapeutic platform in tumor treatment. Compared with conventional cancer treatment strategies, engineering microorganism-based systems provide various distinct advantages, such as the intrinsic capability in targeting tumors, their inherent immunogenicity, in situ production of antitumor agents, and multiple synergistic functions to fight against tumors. Herein, the design, preparation, and application of the engineered microorganisms for advanced tumor therapy are thoroughly reviewed. This review presents a comprehensive survey of innovative tumor therapeutic strategies based on a series of representative engineered microorganisms, including bacteria, viruses, microalgae, and fungi. Specifically, it offers extensive analyses of the design principles, engineering strategies, and tumor therapeutic mechanisms, as well as the advantages and limitations of different engineered microorganism-based systems. Finally, the current challenges and future research prospects in this field, which can inspire new ideas for the design of creative tumor therapy paradigms utilizing engineered microorganisms and facilitate their clinical applications, are discussed.

Perspectives on Genetically Engineered Microorganisms and Their Regulation in the United States.

Genetically engineered microorganisms (GEMs) represent a new paradigm in our ability to address the needs of a growing, changing world. GEMs are being used in agriculture, food production and additives, manufacturing, commodity and noncommodity products, environmental remediation, etc., with even more applications in the pipeline. Along with modern advances in genome-manipulating technologies, new manufacturing processes, markets, and attitudes are driving a boom in more products that contain or are derived from GEMs. Consequentially, researchers and developers are poised to interact with biotechnology regulatory policies that have been in effect for decades, but which are out of pace with rapidly changing scientific advances and knowledge. In the United States, biotechnology is regulated by multiple agencies with overlapping responsibilities. This poses a challenge for both developers and regulators to simultaneously allow new innovation and products into the market while also ensuring their safety and efficacy for the public and environment. This article attempts to highlight the various factors that interact between regulatory policy and development of GEMs in the United States, with perspectives from both regulators and developers. We present insights from a 2022 workshop hosted at the University of California, Berkeley that convened regulators from U.S. regulatory agencies and industry developers of various GEMs and GEM-derived products. We highlight several new biotechnologies and applications that are driving innovation in this space, and how regulatory agencies evaluate and assess these products according to current policies. Additionally, we describe recent updates to regulations that incorporate new technology and knowledge and how they can adapt further to effectively continue regulating for the future.

Biotechnology executive order opens door for regulatory reform and social acceptance of genetically engineered microbes in agriculture.

In the United States, regulatory review of genetically engineered microbes for agriculture falls under the Coordinated Framework for the Regulation of Biotechnology (CFRB). However, the lack of a centralized regulatory pathway and multiple oversight authorities can lead to uncertainty in regulatory review. Using three microbial-based technologies for agriculture as illustrative examples, this commentary identifies the weaknesses and challenges associated with the CFRB by assessing the current system and proposed changes to the system under a multi criteria decision analysis framework. In addition, it discusses opportunities for regulatory reform to improve clarity, efficiency, and public acceptance of genetically engineered microbes in agriculture under the CHIPS and Science Act and the 2022 Executive Order on the Bioeconomy.

Fetoscópica y fotocoagulación láser en el síndrome de transfusión intergemelar: ¿en qué estadio realizarla? una revisión sistemática de la literatura / Fetoscopic and laser photocoagulation in intergemelar transfusion syndrome: in what stage do it? systematic review of the literature

Objetivo: Realizar una revisión sistemática de la literatura que compare la eficacia del tratamiento con fotocoa-gulación láser entre los estadios tempranos vs tardíos en el Síndrome de transfusión intergemelar, según la cla-sificación de Quintero y col. Estrategia de búsqueda: Se realizó una revisión sistemática de la literatura que se llevó a cabo en las bases de datos MEDLINE, PubMed, EMBASE y Cochrane Library, sin limitar la búsqueda de artículos publicados exclusivamente en idioma inglés; las publicaciones se registraron entre enero de 1990 a mar-zo de 2015, con base en las palabras clave: síndrome de transfusión de gemelo a gemelo, la fotocoagulación con láser endoscópica, embarazo de gemelos monocoriales, placenta vasos comunicantes, vasos comunicantes. Resultados: De 67 estudios, con un total de 32 cumplieron los criterios de inclusión, y una revisión sistemática de la literatura técnica se utilizó para estudiar los 8 ensayos controlados aleatorios con 951 mujeres con embarazo gemelar monocorial y síndrome de transfusión de gemelo a gemelo. La supervivencia observada en el síndrome de transfusión de gemelo a gemelo tratados con cirugía láser fetoscópica fue en general el 67 % para ambos fetos y 85 % para un feto; resultados todavía lejos de ser satisfactorios, porque las tasas de mortalidad varían de 20 % a 48 %, sin definir el escenario en el que se debe realizar el procedimiento. Conclusiones: La fotocoagulación con láser bajo guía fetoscópica parece ser el tratamiento óptimo para estadios II a IV, no dependiendo de la técnica quirúrgica; sin delimitar adecuadamente el mejor estadio para realizar este procedimiento.

Objetive: To conduct a systematic review of the literature to define, as rated by Quintero et al., the best stage for treatment with endoscopic laser photocoagulation syndrome twin-twin transfusion. Results: From 67 studies, a total of 32 studies met our inclusion criteria, and a systematic review of the literature technique was used to study the 8 randomized controlled trials involving 951 women with monochorionic twin pregnancy and twin-twin transfusion syndrome. The survival observed in the syndrome of twin-twin transfusion treated with laser surgery fetoscopic was overall 67 % for both fetuses and 85 % for one fetus; results still far from satisfactory, because mor-tality rates range from 20 % to 48 %, without defining the stage on which to perform the procedure. Conclusions: Laser photocoagulation under fetoscopic guide seems to be the optimal treatment for stages II to IV, does not depending on the surgical technique; without adequately delimiting the best stadium to perform this procedure.

Cultivo de la línea celular HEp-2: doblaje poblacional y coloración con Giemsa Perspectivas para el estudio de la infección con Chlamydia trachomatis / Cultivation of the cell line hep-2: dubbing of population and coloring with Giemsa

Los cultivos celulares se han convertido en herramientas esenciales para la investigación básica. Se aplican en inmunología, virología, biología molecular, ingeniería genética y farmacología, entre otras áreas. Se usan también en procesos industriales farmacéuticos, en técnicas de diagnóstico clínico y para estudio de trasplante de tejidos. En bacteriología, estos cultivos permiten confirmar una infección, evaluar la eficiencia de antimicrobianos, realizar estudios de infectividad, investigar sobre nuevas especies, obtener gran cantidad de microorganismos no cultivables para optimizar técnicas y examinar las relaciones entre la célula huésped y los microorganismos intracelulares (virus, bacterias y parásitos). La línea celular HEp-2 (Human Epidermoid Cancer Cells) es utilizada en estudios de infección con diferentes bacterias, entre ellas Chlamydia trachomatis (CT), con el fin de determinar los mecanismos por los cuales este patógeno sobrevive en la célula huésped. También se emplea para observar la acción de péptidos antimicrobianos y de extractos para combatir la infección causada por dicha bacteria. Para este estudio se realizaron curvas de crecimiento en la línea celular HEp-2 con medios DMEM-F12 y MEM. Se estandarizó, además, la coloración con Giemsa y se calculó el doblaje poblacional con diferentes inóculos para evaluar el desarrollo de la línea celular en cultivo y seleccionar las condiciones óptimas para realizar futuros ensayos de infección con parásitos intracelulares, en particular con CT serovar L2.

Cell cultures have become essential tools for basic research. They are applied in immunology, virology, molecular biology, genetic engineering and pharmacology, among other areas. They are also used in pharmaceutical industrial processes, in techniques of clinical diagnostic, and to study tissue transplantation. In bacteriology, these crops allow us to confirm an infection, assess the efficiency of antimicrobials, carry out studies of infectivity, investigate on new species, obtaining a large number of microorganisms non-arable to optimize techniques, and to examine the relationship between the host cell and intracellular microorganisms (bacteria, viruses, and parasites). The HEp-2 cell line (Human epidermoid cancer cells) is used in studies of infection with different bacteria, including Chlamydia trachomatis (CT), in order to determine the mechanisms by which the pathogen survives in the host cell. It is also used to observe the action of antimicrobial peptides and extracts to combat the infection caused by the bacterium. For this study, growth curves of the HEp-2 cell line were carried out with DMEM-F12 and MEM media. In addition, the staining with Giemsa was standardized, and the population dubbing was calculated with different inocula for assessing the development of the cultured cell line and select the optimal conditions for future tests of infection with intracellular parasites, in particular with CT serovar L2.