Cross-Coupling of Mo- and V-Nitrogenases Permits Protein-Mediated Protection from Oxygen Deactivation.

Nitrogenases catalyze dinitrogen (N) fixation to ammonia (NH). While these enzymes are highly sensitive to deactivation by molecular oxygen (O) they can be produced by obligate aerobes for diazotrophy, necessitating a mechanism by which nitrogenase can be protected from deactivation. In the bacterium Azotobacter vinelandii, one mode of such protection involves an O-responsive ferredoxin-type protein ("Shethna protein II", or "FeSII") which is thought to bind with Mo-dependent nitrogenase's two component proteins (NifH and NifDK) to form a catalytically stalled yet O-tolerant tripartite protein complex.

The Mononuclear Metal-Binding Site of Mo-Nitrogenase Is Not Required for Activity.

The biological N-fixation process is catalyzed exclusively by metallocofactor-containing nitrogenases. Structural and spectroscopic studies highlighted the presence of an additional mononuclear metal-binding (MMB) site, which can coordinate Fe in addition to the two metallocofactors required for the reaction. This MMB site is located 15-Å from the active site, at the interface of two NifK subunits.

Nitrogen Fixation and Hydrogen Evolution by Sterically Encumbered Mo-Nitrogenase.

The substrate-reducing proteins of all nitrogenases (MoFe, VFe, and FeFe) are organized as αß(γ) multimers with two functional halves. While their dimeric organization could afford improved structural stability of nitrogenases , previous research has proposed both negative and positive cooperativity contributions with respect to enzymatic activity. Here, a 1.

Community-Led Health Promotion Groups in a Bhutanese-Nepali Refugee Community.

This practice note reports on the work of the Namaste Community Health Partnership, an academic-community partnership established to address health disparities in a metro-area Bhutanese-Nepali refugee community in the western United States. Partners worked together to develop, implement, and evaluate a culturally-tailored health promotion program where Bhutanese-Nepali individuals led weekly walking groups and shared health promotion information and behavior change tools with community participants. The program was implemented with approximately 70 community members across two metro-area neighborhoods and two adult day care centers serving elders.

From ZeRO to HeRO: Saving lives one HeRO at a time.

Introduction: This case report intends to highlight the Haemodialysis Reliable Outflow (HeRO) graft as a potential long term option for ongoing dialysis in patients with central venous stenosis.

Presentation Of Case: A 55year old patient, who developed end stage renal failure (ESRF) after chemotherapy treatment for breast cancer, presented at the limit of her dialysis access after a 15year haemodialysis history causing central vein stenosis. The patient was initially started on peritoneal dialysis but after repeated peritonitis was switched to haemodialysis.

Developing a Systematic Approach to Obstetric Emergencies.

Objective: To determine the effect of standardized education specific to maternal resuscitation on nurses' confidence and competence during obstetric emergencies and to determine the cost savings associated with the program.

Design: Pre- and postintervention surveys designed to measure perceived confidence and competence in resuscitation before and after Advanced Cardiac Life Support (ACLS) certification in combination with obstetric drills.

Setting: The project was conducted at a 12-bed labor and delivery, mother/baby unit in an acute care, community-based hospital in Northwest Arkansas.

Evaluation of pediatric lateral oropharyngeal trauma.

Objective: We reviewed the mechanism of injury, presentation, and evaluation of children with trauma to the lateral oropharynx. Study design and setting We conducted a retrospective review of patients in an urban pediatric emergency department with trauma to the lateral oropharynx over a 5-year period.

Results: Forty-eight patients were identified with documented injuries of the lateral oropharynx placing the internal carotid artery at risk of injury.

Fibroblast behavior in the embryonic chick heart.

Intracardiac fibroblasts (mesenchymal cells) of Hamburger and Hamilton stage 36 chick heart reside in the epicardium and atrioventricular valves. The characteristics of the epicardial fibroblasts include segregation from the myocytes of the heart wall myocardium, voluminous extracellular matrix production, and some cell proliferation activity. The atrioventricular fibroblasts intermingle with myocytes at the mutual border between these tissues, produce smaller amounts of extracellular matrix, and show very active cell proliferation.

Statement: occupational therapy services in work practice.

Occupational therapy practitioners focus on the individual's ability to participate in productive occupations throughout their life span. Through prevention, assessment, and intervention strategies, occupational therapy practitioners often collaborate with other members of the health care team and assist persons to optimize their ability to engage in purposeful occupation while facilitating a safe and successful entry into or return to work.

Preoperative medical consultation and evaluation of surgical risk.

Internists are frequently asked to assess the surgical risk of patients with various medical problems. Numerous recent prospective studies have defined specific risk factors for increased morbidity and mortality in the preoperative evaluation of surgical patients. Careful attention to such factors as age, type of operation and anesthesia, underlying pulmonary, hypertensive, cardiac, renal, hepatic, endocrine, and hematologic diseases, and nutritional status can reduce the complication rate and death rate in surgical patients if specific preoperative, operative, and postoperative therapeutic maneuvers are instituted.

Phosphorus content of bovine rib: influence of earlier biopsy of the same rib.

Serial sampling of bovine rib is undertaken experimentally to monitor changes in the degree of skeletal mineralisation. The validity of this approach depends on the assumption that the previous sampling of a bone does not influence the composition of a sample obtained subsequently. To test this, the effect of a prior biopsy sampling on phosphorus content of the remaining bone was determined at various times after the initial sampling.

Influence of animal age on the tenderness of beef: Muscle differences.

Animal age effects on the mechanical properties of cooked samples from muscles able to cold shorten (Mm. longissimus dorsi, LDA, and semimembranosus, SMA from Achilles tendon hung sides) and muscles partially restrained from shortening (LD muscles from pelvic hung sides, LDP) from groups of animals aged 9, 16, 27 and 42 months were studied. Age effects on stretched muscles (SM muscles from pelvic hung sides, SMP) were determined using groups aged 2 and 120 months in addition to those of 9, 16, 27 and 42 months.