On this basis, we proposed a new algorithm (QAA-Com), a combination of QAA-685 and QAA-715, according to turbidity characterized by a(440). The percentage difference of model retrievals in the visible domain was between 4.5%-45.1%, in average of 18.8% for a(lambda). The QAA model was then applied to Medium Resolution Imaging Spectrometer (MERIS) radiometric products, which were temporally and spatially matched with in-situ optical
measurements. Differences between MERIS retrievals and in-situ values were GW4869 in vivo in the range 9.2%-27.8% for a(lambda) in the visible domain. Major errors in satellite retrieval are attributable to uncertainties of QAA model parameters and in-situ measurements, as well as imperfect atmospheric correction of MERIS data by the
European Space Agency (ESA). During a storm surge in April 2009, time series of MERIS images together with the QAA model were used to analyze spatial and temporal variability of the total absorption coefficient pattern in the Bohai Sea. It is necessary check details to collect more independent field data to improve this algorithm.”
“Nicotinamide nucleotide transhydrogenase (NNT) is an inner mitochondrial membrane transmembrane protein involved in regenerating NADPH, coupled with proton translocation across the inner membrane. We have shown that a defect in Nnt function in the mouse, and specifically within the beta-cell, leads to a reduction in insulin secretion. This chapter describes methods for examining Nnt function in the mouse. This includes generating in vivo models with point mutations and expression of Nnt by transgenesis, and making in vitro models, by silencing of gene expression. In addition, techniques are described to measure insulin secretion, calcium and hydrogen peroxide concentrations, membrane potential, and NNT activity. These approaches and techniques can also be applied to other genes
“Planktonic gross community production (GPP), net community production (NCP) and community respiration (CR) across the Mediterranean Sea was examined in two cruises, Thresholds 2006 and 2007, each crossing the Mediterranean from West to East to test for consistent variation along this longitudinal gradient in late spring to early summer. GPP CH5183284 averaged 2.4 +/- 0.4 mmol O(2) m(-3) d(-1), CR averaged 3.8 +/- 0.5 mmol O(2) m(-3) d(-1), and NCP averaged – 0.8 +/- 0.6 mmol O(2) m(-3) d(-1) across the studied sections, indicative of a tendency for a net heterotrophic metabolism in late spring to early summer, prevalent across studied sections of the Mediterranean Sea as reflected in 70% of negative NCP estimates. The median P/R ratio was 0.6, also indicating a strong prevalence of heterotrophic communities (P/R < 1) along the studied sections of the Mediterranean Sea. The communities tended to be net heterotrophic (i.e. P/R < 1) at GPP less than 2.8 mmol O(2) m(-3) d(-1).
Thus, the ability to maintain paracrine factors and enhance the effectiveness of these growth factors in the wound as well as the simple procedure and economical materials required for production qualifies the FBMSC-CMM to be a candidate biomaterial for open-wound regeneration.”
“Background: Younger ages at diagnosis for blacks compared with whites have been reported for several cancer types. However, the US black population is younger than the white population, which may bias VEGFR inhibitor age comparisons that do not account for the populations at risk. Methods: We analyzed Surveillance, Epidemiology, and End Results data for non-Hispanic blacks and non-Hispanic whites from 18 regions
for the year 2010. We calculated crude mean ages at diagnosis among cases of 29 cancer types for whites and blacks. Separately, we calculated adjusted means that corrected for differences in population structure, which we obtained by fitting linear regression models to the ages at diagnosis with statistical weights specific to age and sex. Negative differences indicate younger ages in blacks, while positive differences indicate older ages in blacks. All statistical tests were two-sided. Results: Based
on crude means, blacks were diagnosed at younger ages than whites for nearly every cancer type. However, adjustment for population structure shifted the comparisons toward older ages among blacks, and only six statistically significant differences of three or more years Selleck GW786034 remained. Blacks were younger than whites at diagnosis for 4-Hydroxytamoxifen Kaposi sarcoma (-10.2 years), male soft tissue cancer (-5.6), male anal cancer (-5.5), and non-Hodgkin’s lymphoma (-3.7), but older for cervical cancer (+4.7 years) and female thyroid cancer (+3.3). Smaller
differences ( smaller than 3 years) were present for female breast, female colon, lung, pancreas, prostate, and uterine corpus cancers (all P = .001). Conclusions: Most differences between blacks and whites in the age at cancer diagnosis are small. Large differences for a few cancer types may be driven by etiologic and subtype heterogeneity as well as disparities in access to care.”
“Mg2+ in various concentrations was added to purified Rubisco in vitro to gain insight into the mechanism of molecular interactions between Mg2+ and Rubisco. The enzyme activity assays showed that the reaction between Rubisco and Mg2+ was two order, which means that the enhancement of Rubisco activity was accelerated by low concentration of Mg2+ and slowed by high concentration of Mg2+. The kinetics constant (K-m) and V-max was 1.91 mu M and 1.13 mu mol CO2 mg(-1) protein.min(-1), respectively, at a low concentration of Mg2+, and 3.45 mu M and 0.32 mu mol CO2.mg(-1) protein.min(-1), respectively, at a high concentration of Mg2+. By UV absorption and fluorescence spectroscopy assays, the Mg2+ was determined to be directly bound to Rubisco; the binding site of Mg2+ to Rubisco was 0.
7%) when combined
with other immunosuppressives (p=1.0). With azathioprine, dosages of systemic immunosuppression and steroids could be reduced by >= 50% (n=12) or topical steroids reduced to <= 2 drops/eye/day in six patients. In three patients (7.3%), azathioprine was discontinued because of nausea and stomach pain.\n\nConclusions Azathioprine may be reconsidered in the stepladder approach for the treatment Wnt inhibitor of JIA-associated uveitis. The addition of azathioprine may also be beneficial for patients not responding properly to methotrexate.”
“The current study examined the role of PLD2 in the maintenance of mast cell structure. Phospholipase D (PLD) catalyzes hydrolysis of phosphatidylcholine to produce choline and phosphatidic acid (PA). PLD has two isoforms, PLD1 and PLD2, which vary in expression and localization depending on the cell type. The mast cell line RBL-2H3 was transfected to overexpress catalytically active (PLD2CA) and inactive (PLD2CI) forms of PLD2. The results of this study show that PLD2CI cells have a distinct star-shaped morphology, whereas PLD2CA and RBL-2H3 cells are spindle shaped. In PLD2CI cells, the Golgi complex was also disorganized
with dilated cisternae, and more Golgi-associated vesicles were present as compared with the PLD2CA and RBL-2H3 cells. Treatment with exogenous PA led to the restoration of the wild-type Golgi complex phenotype in PLD2CI cells. Conversely, treatment Ruboxistaurin cost of RBL-2H3 and PLD2CA cells with 1% 1-Butanol led to a disruption of the Golgi complex. The distribution of acidic compartments, selleck chemicals llc including secretory granules and lysosomes, was also modified in PLD2CI cells, where they concentrated
in the perinuclear region. These results suggest that the PA produced by PLD2 plays an important role in regulating cell morphology in mast cells. (J Histochem Cytochem 60:386-396, 2012)”
“Objective: To describe and interpret the frequently observed spectral-domain optical coherence tomography (SD-OCT) finding of a marked hyporeflective wedge-shaped structure at the boundaries of the areas of atrophy.\n\nDesign: A prospective, longitudinal follow-up study.\n\nParticipants: Consecutive patients (n = 71) 50 years of age and older with geographic atrophy (GA) secondary to age-related macular degeneration (AMD) were examined between January 2010 and June 2011.\n\nMethods: Patients were evaluated with the use of imaging techniques that included 35 fundus photography, infrared, fundus autofluorescence (FAF), and SD-OCT. Visualization of the fundus with FAF was done simultaneously with OCT. Two acquisition protocols were followed: a macular cube for coverage (19 horizontal B-scans centered on the fovea) and high-resolution horizontal B-scan for qualitative foveal detail.\n\nMain Outcomes Measures: Estimation of the prevalence of a hyporeflective wedge-shaped band among patients with GA.
The values of Monod kinetic parameters estimated for the biological treatment of wastewater containing one of these ionic liquids were usually in the range of the values determined for municipal wastewater.
CONCLUSION Newly synthesized tetra- and completely substituted imidazolium ionic liquids are not susceptible to microbial decomposition. At the same time their presence in wastewater neither reduces the growth rate of activated sludge biomass nor decreases the affinity of substrate to biomass. Epigenetic activity inhibition (c) 2013 Society of Chemical Industry”
“It is well known that GnRH analogs can self-assemble into amyloid fibrils and that the duration of action of GnRH analogs depends on the ability of the amyloid to slowly release active peptides. The aim of this study was to investigate the influence of the amino acid residues at position 7 of GnRH analogues on peptide self-assembly. It was found that the dominant shape of the nanostructure can be changed when the structures of the residues at position 7 differ significantly from that of leucine in Degarelix. When the backbone length was extended (peptide 9), or the side chain of the residue at position 7 was replaced by an aromatic ring (peptide 6), or the rotation
of the amide bond was restricted (peptide 8), the nanostructure changed from fibrils to vesicles. The results also indicate that the increasing hydrophilicity Roscovitine had little influence on the nanostructure morphology. In addition, a suitable release
rate was found to play a more important role for the duration of the peptide action by maintaining the equilibrium between the drug concentration ON-01910 molecular weight and the persistent release time, while the nanostructure shape was found to exert little influence on the duration of the peptide action. Copyright (c) 2014 European Peptide Society and John Wiley & Sons, Ltd.”
“Background: Indacaterol is an inhaled, once-daily, ultra-long-acting beta(2)-agonist for the treatment of chronic obstructive pulmonary disease (COPD). We report on the effectiveness of indacaterol and other bronchodilators compared with placebo in patients across the Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2011 categories A to D. Methods: A post-hoc, subgroup pooled analysis of 6-month efficacy data from three randomized, placebo-controlled, parallel-group studies involving 3862 patients was performed across GOLD 2011 categories A to D, according to baseline forced expiratory volume in 1 s (FEV1) % predicted, modified Medical Research Council (mMRC) dyspnea scale, and exacerbation history in the 12 months prior to entry. Efficacy of once-daily indacaterol 150 and 300 mu g, open-label tiotropium 18 mu g, twice-daily salmeterol 50 mu g, and formoterol 12 mu g was compared with placebo.
These results suggest that Viscum album can enhance Immoral and cellular immune responses in cancer patients, but further studies attesting to the possible clinical impact of these immunological effects are
necessary. Copyright (C) 2008 John Wiley & Sons, Ltd.”
“Cardiac complications from brucellosis are unusual and usually manifest as endocarditis. The other possible complication is myocardial involvement. Brucella myocarditis and development of heart failure is a very rare complication of brucellosis. We present a patient with new onset heart failure due to brucella myocarditis treated with favorable antibiotic therapy.”
“Interaction of ligands with their specific receptors is accompanied by conformational shifts culminating in receptor activation and expression of hormonal activity. Using an engineered disulfide bond formation strategy, we characterized the relative conformational changes taking place MK-0518 within the PTH type 1 receptor (PTHR1) at the interface of transmembrane (TM)5 and TM6 on binding the PTH agonist, PTH(1-34), compared with the antagonist PTH(7-34). Cysteines were
singly incorporated into a portion of the extracellular-facing region of TM5 (365-370), while simultaneously a second cysteine was introduced at position 420, 423, or 425 at the extracellular end of TM6, leading to a total of 18 double cysteine-containing PTHR1. mutants. All mutants, except P366C/V423C and P366C/M425C, were expressed in the cell EGFR inhibitor membrane preparations. In the presence of GW4869 supplier agonist, H420C and M425C in TM6 formed disulfide bonds with all and with most, respectively, of the substituted cysteines incorporated fit TM5. In contrast to the conformational shift induced (or stabilized) by agonist in activating the receptor, antagonist binding produced no detectable change from the basal (inactive)
conformation of PTHR1. Our studies provide physicochemical evidence that the extracellular-facing ligand binding regions of receptor, TM5 and TM6, are dynamic and move relative to each other on ligand binding. The distinct differences in receptor conformation induced (or stabilized) by agonist PTH(1-34) compared with antagonist PTH(7-34) begin to provide insight into the early events in and mechanism of PTHR1 activation.”
“IL-17-producing Th17 cells mediate immune responses against a variety of fungal and bacterial infections. Signaling via NF-kappa B has been linked to the development and maintenance of Th17 cells. We analyzed the role of the unusual inhibitor of NF-kappa B, I kappa B-NS, in the proliferation and effector cytokine production of murine Th17 cells. Our study demonstrates that nuclear I kappa B-NS is crucial for murine Th17 cell generation. I kappa B-NS is highly expressed in Th17 cells; in the absence of I kappa B-NS, the frequencies of IL-17A-producing cells are drastically reduced.
Scratching analysis and measurement of transepidermal water loss were performed every other week. The pathological condition of the dorsal skin was evaluated histologically. Real-time polymerase chain reaction analysis was performed for cytokine expression in the affected skin. The epidermal hyperplasia and allergic
inflammation were reduced in atopic mice supplied with Jeju groundwater when compared to those supplied with tap water or other kinds of natural groundwater. The increase in scratching behavior with the aggravation of clinical severity of dermatitis was favorably controlled. Moreover, transepidermal water loss that reflects skin barrier function was recovered. The early inflammation and hypersensitivity in the atopic skin was alleviated in mice supplied with Jeju groundwater, suggesting its profitable potential on the daily care of patients with skin troubles including AD.”
“During our careful surveillance of unregulated drugs, selleck screening library we found five new compounds used as adulterants in herbal and drug-like products obtained via the Internet. These compounds were identified by liquid chromatography-mass spectrometry, gas chromatography-mass spectrometry, accurate mass spectrometry, and nuclear magnetic resonance
spectroscopy. The first compound identified was a benzoylindole AM-694, which is 1-[(5-fluoropentyl)-1H-indol-3-yl]-(2-iodophenyl)methanone (1). The second compound was (4-methoxyphenyl)(1-pentyl-1H-indol-3-yl)methanone (2), which was also classified as a benzoylindole. The three other compounds were identified as naphthoylindoles JWH-210 (4-ethylnaphthalen-1-yl-(1-pentylindol-3-yl)methanone; A-1155463 inhibitor 3), JWH-122 (4-methylnaphthalen-1-yl-(1-pentylindol-3-yl)methanone; 4), and JWH-019 (1-hexyl-3-(naphthalen-1-oyl)indole; 5). All compounds except compound 2 had been reported to be cannabinoid
receptor agonists. For quantitation of the five compounds and previously reported compounds, each product was extracted with methanol under ultrasonication to prepare a test solution for analysis by liquid chromatography with ultraviolet detection. Each compound detected in 43 commercial products showed large variation in content ranging from 4.0 to 359 mg per pack.”
“We present several bioinformatics applications for DMH1 the identification and quantification of phosphoproteome components by MS. These applications include a front-end graphical user interface that combines several Thermo RAW formats to MASCOTTM Generic Format extractors (EasierMgf), two graphical user interfaces for search engines OMSSA and SEQUEST (OmssaGui and SequestGui), and three applications, one for the management of databases in FASTA format (FastaTools), another for the integration of search results from up to three search engines (Integrator), and another one for the visualization of mass spectra and their corresponding database search results (JsonVisor).
Furthermore, results showed no significant difference between
locomotor rhythm pattern of males and females of this species.”
“Aim: To examine whether physical activity increases osteogenic differentiation of bone marrow mesenchymal stem cells (BMMSCs) from adult rats compared with young rats.\n\nMethods: Eighteen female Wistar rats were divided into three groups and the following cells isolated: (1) differentiated BMMSCs from young donors, (2) differentiated BMMSCs Selleckchem CT99021 from sedentary adult donors and (3) differentiated BMMSCs from active adult donors. We analysed MTT conversion, percentage of cells per field, mineralized nodule number and gene expression for telomerase reverse transcriptase (TERT), alkaline phosphatase, caspase 3, osteocalcin, bone sialoprotein and collagen I.\n\nResults: Telomerase reverse transcriptase expression and the percentage of cells per field in BMMSCs cultures from adult rats were smaller than those observed in young donors. However, levels of caspase 3 expression were higher in BMMSCs from adult donors (P<0.05). Despite the fact that physical activity was associated with an increase
in expression of caspase 3 (P<0.05), there was no difference in the percentage of cells per field between groups of adult BMMSCs (active or sedentary). However, physical activity increased the number of mineralized nodules and osteocalcin expression after 21days, and alkaline phosphatase expression at 7, 14 and 21days in the BMMSCs of adult donors (P<0.05). Bindarit price However, those values were smaller when compared with young donors BMMSCs (P<0.05). Only the expression levels of alkaline Torin 2 PI3K/Akt/mTOR inhibitor phosphatase were similar to young donors BMMSCs (P=0.05).\n\nConclusion: Physical activity increases osteogenic differentiation of
BMMSCs from adult donors but does not increase the differentiation to the levels observed in BMMSCs from young donor rats.”
“Background information. The p24 protein family plays an important but unclear role at the ER (endoplasmic reticulum)-Golgi interface. A p24 member from each subfamily (p24 alpha(3), beta(1), gamma(3) and delta(2)) is upregulated with the prohormone POMC (pro-opiomelanocortin) when Xenopus laevis intermediate pituitary melanotrope cells are physiologically activated. Here we explored the role of p24 by generating and analysing Xenopus with melanotrope cell-specific transgene expression of p24 beta(1) or p24 gamma(3), two of the p24 proteins coexpressed with POMC, and compared the results with those previously reported for the two other coexpressed p24s (p24 alpha(3) and p24 delta(2)).\n\nResults. The transgene expression of p24 beta(1) or p24 gamma(3) did not affect the endogenous p24 proteins or affected only endogenous p24 gamma(3) respectively, whereas in transgenics expressing p24 alpha(3) and p24 delta(2), the levels of all endogenous p24 proteins were strongly decreased.
Y(2)O(3) nanocrystals (YO NC) doped
selleck in situ with fluorescent (Eu(3+)) and paramagnetic (Gd(3+)) impurities and conjugated with a potential cancer targeting ligand, folic acid (FA), were prepared using an all-aqueous wet-chemical process. Structural, optical and magnetic properties of these multifunctional nanocrystals were investigated by X-ray diffraction, electron microscopy, photoluminescence and magnetization studies. Highly monodisperse nanocrystals of size similar to 20 nm with cubic bixbyite crystal structure showed bright red-fluorescence when doped with Eu(3+). Co-doping with Gd(3+) and mild air drying resulted significantly enhanced fluorescence quantum efficiency of similar to 60% together with paramagnetic functionality, enabling T(1)-weighted MR contrast with similar to 5 times higher spin-lattice relaxivity compared to the clinically used Gd(3+) contrast agent. Cytotoxicity and reactive oxygen stress studies show no toxicity by YO NC in both normal and cancer cells up to higher doses of 500 mu M and longer incubation time, 48 h. Cancer targeting
capability of FA conjugated NCs was demonstrated on check details folate receptor positive (FR+) human nasopharyngeal carcinoma cells (KB) with FR depressed KB (FRd) and FR negative (FR-) lung cancer cells A549 as controls. Fluorescence microscopy and flow-cytometry data show highly specific binding and cellular uptake of large concentration of FA conjugated NCs on FR+ve cells compared to the controls. Thus, the present study reveals, unique bi-modal contrast imaging capability, non-toxicity and cancer targeting capability of multiple impurities doped rare-earth
oxide nanocrystals that can find promising application in molecular imaging. (C) 2009 Elsevier Ltd. All rights reserved.”
“Mechanisms that bring about coordination of cell growth and cell division in different organisms are biological events not yet clearly revealed. In maize, insulin effector of the phosphatidylinositol 3-kinase (PI3K)-target of rapamycin (TOR) signal transduction pathway in metazoan or an intrinsic maize growth factor similar to insulin has shown to regulate cell growth. buy Silmitasertib This research has been undertaken to analyze the role of PI3K-TOR signal transduction pathway in maintaining coordinated regulation of cell growth and cell division in maize tissues. Results indicate that DNA synthesis as well as mitotic index increased in maize callus in vitro cultures after insulin or maize factor stimulation. Biomass and ribosomal protein synthesis also showed significant increment after this stimulation, and the cell morphology composition of the cultures drastically changed. Two proteins related to cell cycle, D-type cyclins and proliferating cell nuclear antigen, were selectively synthesized under these conditions.
Methods. We conducted a multisite
cohort study of 3672 antiretroviral-naive patients initiating antiretroviral therapy (ART) during 2000-2010. Retention in care was measured by the IOM and DHHS core indicators (2 attended visits at defined intervals per 12-month period), and also as a count of missed primary ACY-241 clinical trial HIV care visits (no show) during a 24-month measurement period following ART initiation. All-cause mortality was ascertained by query of the Social Security Death Index and/or National Death Index, with adjusted survival analyses starting at 24 months after ART initiation. Results. Among participants, 64% and 59% met the IOM and DHHS retention core indicators, respectively, PDGFR inhibitor at 24 months.
Subsequently, 332 patients died during 16 102 person-years of follow-up. Failure to achieve the IOM and DHHS indicators through 24 months following ART initiation increased mortality (hazard ratio [HR] = 2.23; 95% confidence interval [CI], 1.79-2.80 and HR = 2.36; 95% CI, 1.89-2.96, respectively). Among patients classified as retained by the IOM or DHHS clinical core indicators, bigger than 2 missed visits further increased mortality risk (HR = 3.61; 95% CI, 2.35-5.55 and HR = 3.62; 95% CI, 2.30-5.68, respectively). Conclusions. Beyond HIV retention core indicators, missed clinic visits were independently associated with all-cause mortality. Caution is warranted in relying solely
upon retention in care core indicators for policy, clinical, and programmatic purposes.”
“Oxidation of DNA due to exposure to reactive oxygen species is a major source of DNA damage. One of the oxidation lesions formed, 5-hydroxy-2′-deoxycytidine, has been shown to miscode by some replicative DNA polymerases but not by error https://www.selleckchem.com/products/INCB18424.html prone polymerases capable of translesion synthesis. The 5-hydroxy-2′-deoxycytidine lesion is repaired by DNA. glycosylases that require the 5-hydroxycytidine base to be extrahelical so it can enter into the enzyme’s active site where it is excised off the DNA backbone to afford an abasic site. The thermodynamic and nuclear magnetic resonance results presented here describe the effect of a 5-hydroxy-2′-deoxycytidine center dot 2′-deoxyguanosine base pair on the stability of two different: DNA duplexes. The results demonstrate that the lesion is highly destabilizing and that the energy barrier for the unstacking of 5-hydroxy-2′-deoxycytidine from the DNA duplex may be low. This could provide a thermodynamic mode of adduct identification by DNA glycosylases that requires the lesion to be extrahelical.”
“The objective of this work was to examine immediate physiological plant responses to hail and subsequent recovery in terms of evapotranspiration, leaf temperature and primary photochemical processes using apple as a model crop.
Treatment of a p38MAP kinase inhibitor, SB203580 (10 mu mol/l), and a JNK inhibitor, SP600125 (20 mu mol/l), abrogated the [(3)H]-leucine incorporation by insulin in the presence of Ang II. Both the Ang II receptor blocker, RNH-6270 (100 nmol/l), and an antioxidant, ebselen (40 mu mol/l), inhibited vascular cell hypertrophy. Specific depletion of insulin receptor substrate-1 with small interfering RNA increased [(3)H]-leucine
incorporation by insulin (10 nmol/l, 24 h); pretreatment with Ang II attenuated insulin (10 nmol/l, 30 min)-induced glucose uptake.\n\nCONCLUSIONS\n\nAng II attenuates insulin-stimulated glucose uptake and enhances vascular cell hypertrophy via oxidative stress- and MAP kinase-mediated pathways in VSMCs. Ang II may also cause insulin signaling to Epacadostat in vivo diverge from glucose metabolism into vascular remodeling, affecting insulin-induced arteriosclerosis in hypertension.”
“Electrochromic switchable mirrors are expected to be used in energy-saving windows because their optical properties can be changed by application of a voltage. For practical use, the negative impact of environmental conditions on the optical switching properties of the device should be
minimized. In this work, the durability of an electrochromic device was JQ1 mouse investigated in a thermostat/humidistat chamber at -5 degrees C. After devices were stored at sub-zero temperatures, the switching speed and maximum transmittance decreased only Nirogacestat slightly with increasing exposure time. In other words, degradation of the device did not significantly occur at sub-zero temperatures. In comparison, the optical switching properties of a device stored at 40 degrees C and 60% relative humidity severely deteriorated. This deterioration was attributed to the degradation of the surface of the Mg4Ni optical switching layer. This layer was affected by the environmental conditions, and in particular changed from the metallic magnesium state to a non-metallic state. In
future work, we will investigate suitable measures for preventing environmental damage to the device. (C) 2012 Elsevier B.V. All rights reserved.”
“Intransitive communities, those in which species’ abilities cannot be ranked in a hierarchy, have been the focus of theoretical and empirical research, as intransitivity could help explain the maintenance of biodiversity. Here we show that models for intransitive competition embedding slightly different interaction rules can produce opposite patterns. In particular, we find that interactions in which an individual can be outcompeted by its neighbors, but cannot outcompete its neighbors, produce negative frequency dependence that, in turn, promotes coexistence. Whenever the interaction rule is modified toward symmetry (the individual and the neighbors can outcompete each other) the negative frequency dependence vanishes, producing different coexistence levels.