Phosphate-Arsenic Interactions in Halophilic Microorganisms of the Microbial Mat from Laguna Tebenquiche: from the Microenvironment to the Genomes.

Arsenic (As) is a metalloid present in the earth's crust and widely distributed in the environment. Due to its high concentrations in the Andean valleys and its chemical similarity with phosphorus (P), its biological role in Andean Microbial Ecosystems (AMEs) has begun to be studied. The AMEs are home to extremophilic microbial communities that form microbial mats, evaporites, and microbialites inhabiting Andean lakes, puquios, or salt flats. In this work, we characterize the biological role of As and the effect of phosphate in AMEs from the Laguna Tebenquiche (Atacama Desert, Chile). Using micro X-ray fluorescence, the distribution of As in microbial mat samples was mapped. Taxonomic and inferred functional profiles were obtained from enriched cultures of microbial mats incubated under As stress and different phosphate conditions. Additionally, representative microorganisms highly resistant to As and able to grow under low phosphate concentration were isolated and studied physiologically. Finally, the genomes of the isolated Salicola sp. and Halorubrum sp. were sequenced to analyze genes related to both phosphate metabolism and As resistance. The results revealed As as a key component of the microbial mat ecosystem: (i) As was distributed across all sections of the microbial mat and represented a significant weight percentage of the mat (0.17 %) in comparison with P (0.40%); (ii) Low phosphate concentration drastically changed the microbial community in microbial mat samples incubated under high salinity and high As concentrations; (iii) Archaea and Bacteria isolated from the microbial mat were highly resistant to arsenate (up to 500 mM), even under low phosphate concentration; (iv) The genomes of the two isolates were predicted to contain key genes in As metabolism (aioAB and arsC/acr3) and the genes predicted to encode the phosphate-specific transport operon (pstSCAB-phoU) are next to the arsC gene, suggesting a functional relationship between these two elements.

Tuberculosis: the latest.

Tuberculosis (TB) is a complex disease with a long history of human infection. This article provides an overview of TB and discusses ramifications for anesthesia practitioners. Specific individuals and groups are at an increased risk of developing TB. The acid-fast bacilli that causes TB is transmitted via the airborne route. The anesthesia provider must adapt his/her approach to the patient with TB so that protection is afforded that practitioner, colleagues, and the patient. Future patients are also shielded from potential exposure to acid-fast bacilli. To minimize the risk of transmission of acid-fast organisms, the anesthesia practitioner must consider TB as a possible diagnosis when performing a preanesthetic evaluation. Standard precautions for bloodborne pathogens must be followed. In addition, appropriate respiratory precautions must be taken. Proper cleansing, decontaminating, sterilizing, or disposal of equipment must occur. Screening of anesthesia providers for the possibility of infection with TB is to be conducted at intervals recommended by the Occupational Safety and Health Administration. Each anesthetist has a responsibility to practice safely. In today's anesthesia practice, safety includes vigilance against TB.

AANA Journal Course: update for nurse anesthetists--management of malignant ventricular tachyarrhythmias: the role of drug therapy and surgical intervention in sudden cardiac death survivors.

The use of implantable cardioverter-defibrillators (ICDs) to treat patients with ventricular tachyarrhythmias and sudden cardiac death (SCD) has increased over the last decade. Once applied as therapy of last resort, new surgical techniques and improved technology have made the procedure relatively noninvasive. As a result, it is becoming increasingly more common for patients to undergo insertion of this life-saving device in nonoperating room locations. Because patients who require insertion of ICDs often have significant underlying cardiac disease, developing a plan of anesthesia management tailored to meet their needs and predispositions may be a challenge. This Journal Course reviews, from an historical as well as contemporary perspective, the medical and surgical management of patients with ventricular tachyarrhythmias at risk to sustain SCD. A case presentation format is utilized to illustrate an example of an anesthetic plan of care for a patient who underwent insertion of an ICD. Additional information is presented regarding the impact of the ICD on quality of life and overall healthcare costs. As our healthcare system continues to change and evolve, when treatment options are considered, quality of life and cost issues are becoming increasingly more important.