Comammox Nitrospira Clade B is the most abundant complete ammonia oxidizer in a dairy pasture soil and inhibited by dicyandiamide and high ammonium concentrations.

The recent discovery of comammox Nitrospira, a complete ammonia oxidizer, capable of completing the nitrification on their own has presented tremendous challenges to our understanding of the nitrification process. There are two divergent clades of comammox Nitrospira, Clade A and B. However, their population abundance, community structure and role in ammonia and nitrite oxidation are poorly understood. We conducted a 94-day microcosm study using a grazed dairy pasture soil amended with urea fertilizers, synthetic cow urine, and the nitrification inhibitor, dicyandiamide (DCD), to investigate the growth and community structure of comammox Nitrospira spp. We discovered that comammox Nitrospira Clade B was two orders of magnitude more abundant than Clade A in this fertile dairy pasture soil and the most abundant subcluster was a distinctive phylogenetic uncultured subcluster Clade B2. We found that comammox Nitrospira Clade B might not play a major role in nitrite oxidation compared to the role of canonical Nitrospira nitrite-oxidizers, however, comammox Nitrospira Clade B is active in nitrification and the growth of comammox Nitrospira Clade B was inhibited by a high ammonium concentration (700 kg synthetic urine-N ha-1) and the nitrification inhibitor DCD. We concluded that comammox Nitrospira Clade B: (1) was the most abundant comammox in the dairy pasture soil; (2) had a low tolerance to ammonium and can be inhibited by DCD; and (3) was not the dominant nitrite-oxidizer in the soil. This is the first study discovering a new subcluster of comammox Nitrospira Clade B2 from an agricultural soil.

Anterior Shoulder Instability: A Systematic Review of the Quality and Quantity of the Current Literature for Surgical Treatment.

BACKGROUND: Anterior shoulder instability is the most common sequela of shoulder dislocation and can result in repeated dislocations or subluxation of the glenohumeral joint. Anterior shoulder instability can be treated conservatively or surgically with several procedures. PURPOSE: To date, arthroscopic Bankart is the most common surgical procedure for the treatment of anterior shoulder instability. No previous studies have compared all anterior shoulder surgical procedures. In this study, the authors performed a systematic review of journal articles describing all surgical procedures for anterior shoulder instability to determine the scientific evidence and level of recommendation. STUDY DESIGN: Systematic review; Level of evidence, 4. METHOD: A comprehensive literature search was conducted (July 19, 2016) with 4 reputed databases: PubMed, EMBASE, the Cochrane databases, and Web of Science. The articles found in the literature search were screened by 2 reviewers on the basis of their titles, abstracts, and full text. Data were extracted from relevant studies, and potentially relevant records were selected for full-text review. Included articles were classified according to their scientific quality (level of evidence, 1-5). The studies were then combined for each surgical procedure, and a grade of recommendation was assigned for each procedure: grade A, treatment recommendation based on level 1 evidence studies; B, based on level 2 or 3 evidence studies; C, based on level 4 or 5 evidence and could represent conflicting results; or I, insufficient evidence to recommend a treatment. As such, the grade of recommendation provides a summary score for the quality and quantity of available literature to support the surgical procedures reviewed here. RESULTS: The systematic literature review generated 11,281 articles. After screening, 655 articles were included. Results revealed 31 surgical procedures for shoulder instability following dislocation: 10 surgical procedures were given an A or B recommendation; 11, a C recommendation; and 10, an I recommendation. CONCLUSION: This review identified many surgical procedures to treat anterior shoulder instability. Ten of these surgical procedures had an abundant amount of published articles to describe their safety and efficacy. Arthroscopic Bankart and open Bankart were the most commonly reported procedures that cite satisfactory postoperative outcomes and limited complications. Publications on the other surgical procedures were less common. Surgeons should be careful when recommending surgery, and they should choose the appropriate surgical procedure based on evidence-based literature.

The value of a carotid duplex surveillance program for stroke prevention.

BACKGROUND: Although duplex ultrasonography (DU) can readily identify progression of carotid stenosis, controversy regarding the natural history of asymptomatic carotid stenosis as well as the need and appropriate interval for carotid DU surveillance still exists. Furthermore, consensus has not yet been made in the surgical literature regarding the usefulness, cost-effectiveness, or timing of DU surveillance after carotid endarterectomy (CEA). The purpose of this study was to determine how often DU surveillance for asymptomatic carotid disease or postintervention stenosis resulted in any change in the patient's clinical management, how many strokes were prevented by DU surveillance, and the cost of such a DU surveillance program per stroke prevented. METHODS: We reviewed a 9-year vascular surgical database to identify all patients enrolled in a carotid DU surveillance program for asymptomatic carotid stenosis or following CEA between January 1, 2000, and December 31, 2008. The number of duplex scans and CEAs performed in those patients through March 2010 was also determined. The results of the Asymptomatic Carotid Atherosclerosis Study were then used to estimate the number of strokes prevented by CEA in the study population. Reimbursement data were assessed to calculate the average cost of each DU and the cost of the DU surveillance program for each stroke prevented. RESULTS: During the study period, there were 11,531 carotid duplex scans performed on 3,003 patients (mean: 3.84 scans per patient) who had been enrolled in the DU surveillance program. CEA for asymptomatic carotid stenosis was performed on 225 (7.5%) patients. The DU surveillance program prevented approximately 13 strokes (871 carotid duplex scans per stroke prevented). The mean cost of each duplex scan was $332 ± 170. The total cost of the DU surveillance program was approximately $3,830,000 or $290,000 per stroke prevented. CONCLUSIONS: Although a carotid DU surveillance program generates substantial revenue for a vascular surgery practice, it is costly and inefficient. A reappraisal of the "value" of carotid DU surveillance in stroke prevention is warranted. Consideration should be given to eliminating routine surveillance of postendarterectomy carotids in the absence of contralateral disease and limiting the number of DU surveillance studies for asymptomatic carotid disease.

Capillary electrophoresis-mass spectrometry: recent advances to the analysis of small achiral and chiral solutes.

We describe here the state-of-the-art development of on-line capillary electrophoresis-mass spectrometry (CE-MS) over the last two years. Technological developments included are novel designs of new interfaces and ionization sources, new capillary coatings, buffers, and micelles as well as application of various modes of CE-MS published in the recent literature. The areas of CE-MS application in analysis of small achiral and chiral solutes are covered in sections that highlight the recent advances and possibilities of each mode of CE-MS. Application areas reviewed in this paper include achiral and chiral pharmaceuticals, agrochemicals, carbohydrates, and small peptides. The separation of enantiomers using micellar electrokinetic chromatography (MEKC)-MS with molecular micelles and capillary electrochromatography (CEC)-MS using pack tapered columns appears to provide good tolerance to electrospray stability for routine on-line CE-MS. These two modes seem to be very suitable for sensitive detection of chiral pharmaceuticals in biological samples, but their use will probably increase in the near future. Overall, it seems that one mode of CE-MS, in particular capillary zone electrophoresis (CZE)-MS, is now recognized as established technique for analysis of small charged solutes, but other modes, such as MEKC-MS and CEC-MS, are still within a period of development in terms of both MS-compatible pseudostationary phases and columns as well as applications.

Effect of anticardiolipin/beta2-glycoprotein I complexes on production of thromboxane A2 by platelets from patients with the antiphospholipid syndrome.

OBJECTIVE: Antiphospholipid antibodies (aPL) reactive with anionic phospholipids and beta2-glycoprotein I (beta2-GPI) are found in the sera of patients with autoimmune diseases. Clinically, aPL/beta2-GPI complexes are associated with arterial and venous thrombosis, fetal loss, and thrombocytopenia, i.e., the antiphospholipid syndrome (APS). The mechanism of thrombosis is not known. We hypothesized that aPL/beta2-GPI complexes could perturb the platelet membrane and increase production of thromboxane A2 (TXA2, a proaggregatory prostanoid). METHODS: We isolated an IgG fraction containing anticardiolipin antibody (aCL) and the plasma cofactor, beta2-GPI, from a patient with a high titer of aCL and thrombotic cerebrovascular disease. We then examined the effect of aCL, beta2-GPI, and the aCL/beta2-GPI complex on platelet TXB2 (a stable metabolite of TXA2) biosynthesis in vitro from 7 healthy controls. We also measured in vitro platelet TXB2 biosynthesis in 7 patients with APS and in 8 controls. RESULTS: We found: (1) significantly increased in vitro TXB2 production by platelets from controls after incubation with aCL/beta2-GPI complexes; (2) moderately increased TXB2 production by aCL alone; (3) no increase in TXB2 production by beta2-GPI alone; and (4) significantly increased 11-dehydro-TXB2, a metabolite of TXB2 production in vivo, in the urine of patients with APS compared with controls. CONCLUSION: These data suggest that aCL/beta2-GPI complexes play a role in activating platelets to produce TXA2, which could contribute to the prothrombotic state found in patients with APS.

Transpiration rates and canopy conductance of Pinus radiata growing with different pasture understories in agroforestry systems.

We measured tree transpiration and canopy conductance in Pinus radiata D. Don at two low rainfall sites of differing soil fertility in Canterbury, New Zealand. At the more fertile Lincoln site, we also assessed the effects of two common pasture grasses on tree transpiration and canopy conductance. At the less fertile Eyrewell Forest site, the effect of no understory, and the effects of irrigation in combination with mixtures of grass or legume species were determined. Tree xylem sap flux (F(d)') was measured by the heat pulse method. Total canopy conductance to diffusion of water vapor (G(t)) was calculated by inverting a simplified Penman-Monteith model. The different treatment effects were modeled by the simple decaying exponential relationship G(t) = G(tmax)e((-bD)), where D = air saturation deficit. At the Lincoln site, trees with an understory of cocksfoot had lower F(d)' and G(tmax) than trees with an understory of ryegrass, although the sensitivity of G(t) to increasing D (i.e., the value of b) did not differ between treatments. At the Eyrewell site, irrigation only increased F(d)' in the absence of an understory, whereas the presence of understory vegetation, or lack of irrigation, or both, significantly reduced G(tmax) and increased b. We conclude that the selection of understory species is critical in designing successful agroforestry systems for low rainfall areas.

Isolation and purification of anticardiolipin antibody from plasma of a patient with antiphospholipid syndrome: induced generation of platelet thromboxane A2 synthesis.

Antiphospholipid antibodies, particularly anticardiolipin antibodies (aCL) are autoantibodies frequently detected in the serum of patients with systemic lupus erythematosus (SLE) and the primary antiphospholipid antibody syndrome (PAPS). These patients commonly suffer from thrombosis, recurrent fetal loss and thrombocytopenia. Since platelet aggregation is pivotal in the genesis of thrombosis, we tested the hypothesis that perturbation of platelet membrane by aCL/beta 2-glycoprotein (aCL/beta 2GP) complex could trigger the biosynthesis of TXA2, a proaggregatory metabolite of AA. The preincubation of 14C-arachidonic acid (14C-AA)-labeled platelet pellets (14C-PP) from normal individuals with aCL alone followed by incubation with thrombin, resulted in a moderate increase in platelet thromboxane B2 (14C-TXB2) biosynthesis when compared to controls (without aCL). Similar incubations with beta 2GP-I alone resulted in negligible 14C-TXB2 biosynthesis. In contrast, the preincubations of normal 14C-PP with aCL/beta 2GP-I complex resulted in marked thrombin-induced TXB2 biosynthesis, underscoring the requirement of beta 2GP-I in aCL-induced platelet TXB2 biosynthesis. Taken together, these results are consistent with the view that aCL/beta 2GP-I platelet interactions do play a role, at least in part, in platelet hyperactivity and thrombosis in antiphospholipid antibody syndrome.

Immunologic mechanisms in common rheumatologic diseases.

Rheumatoid arthritis and seronegative spondyloarthropathies are rheumatologic diseases that likely are caused by inflammatory reactions occurring in genetically predisposed individuals mounting an immune response to the antigen. Understanding the immunopathology of these diseases provides insight into their etiology, pathogenesis, and a rationale for therapies targeting immune component interactions. Although the antigen in rheumatoid arthritis is not known, several bacterial antigens have been associated with seronegative spondyloarthropathies. These antigens result in an interaction between the human leukocyte antigen-B27 restricted CD8 positive T lymphocytes and the antigen presenting cell, producing an inflammatory response. Rheumatoid factors are autoantibodies directed against the fragment crystallizable portion of the immunoglobulin G. Rheumatoid factor immunoglobulin G immune complexes contribute to the inflammatory events in the rheumatoid joint, and may play an important role in antigen presentation. A novel antigen capture enzyme linked immunosorbent assay was developed that mimicked B cell surface expressed rheumatoid factor. Conversely, a direct binding enzyme linked immunosorbent assay mimicked secreted rheumatoid factor. Comparison of rheumatoid binding enzyme linked immunosorbent assays showed that the physical state of rheumatoid factor can affect binding characteristics. The state of glycosylation of immunoglobulin G may contribute to its antigenic structure. These physical characteristics may be important in rheumatoid factor's pathogenic role in rheumatoid arthritis.

Rheumatoid arthritis: new science, new treatment.

Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease that occurs two to four times as often in women as in men and increases in incidence with advancing age. It affects synovial-lined joints and can also affect the pulmonary, cardiac, nervous, integumentary, and reticuloendothelial systems. RA is manifested clinically by malaise and fatigue, followed by a symmetric pattern of joint inflammation characterized by pain and stiffness. RA most likely occurs in the setting of a genetically predisposed individual, triggered by infectious agents or endogenous antigens. Many of the newer treatments being studied involve blocking cytokine-mediated interactions between cells of the synovium.

Acute gout involving the acromioclavicular joint following treatment with gemfibrozil.

Gout affecting the acromioclavicular joint is extremely rare. We describe a case of acute gout involving the acromioclavicular joint in a patient with seronegative spondyloarthropathy, following use of the fibric acid derivative, gemfibrozil. This case broadens the differential diagnosis of acute acromioclavicular joint arthritis; further studies are needed to determine if there is a causal relationship between use of gemfibrozil and an acute attack of gout.